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Introduction to Plant Agriculture
AGR*2470 University of Guelph
1213
Agriculture
Undergraduate 2
10/12/2014

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Cards

Term
4 F's
Definition

Food, feed, fibre, and fuel.

Also: "farmaceuticals", flavours, and fun.

Term
Abiotic environmental factors
Definition
Non-living factors. Temperature, radiation, moisture. Plants are non-motile, so them have to deal with these factors where they are.
Term
Abonera system
Definition
Row intercropping of velvet bean and corn. High labour productivity. Popular in Honduras.
Term
Absolute growth curve (G)
Definition

The speed of growth graphed over time. The derivative of the culumulative growth. A bell-shaped line.

W = weight

t = time

G = (W2 - W1) / (t2 - t1)

Term
Acclimation
Definition
Increase in cold-hardiness of plant tissues. Occurs in the autumn in perennials. Antifreeze proteins are made inthe cell. The cell membrane goes through alterations.
Term
Accretional growth
Definition
Growth restricted to certain points. The meristems.
Term
Accumulated CHU
Definition
The sum of the daily CHU for a given growing season.
Term
Acidic
Definition
Has a lower pH.
Term
Active far-red-absorbing phytochrome (Pfr)
Definition
The form of phytochrome when exposed to red light. In darkness it turns into inactive red-absorbing phytochrome.
Term
Active uptake
Definition

aka Accumulation

Roots taking up nutrients in higher concentrations than they could with simple osmosis. Uses ATP to create an electrochemical gradient. H+ ions are pumped into the apoplasm, causing ions to go into the symplasm through membrane-bound transporters.

Term
Additive design
Definition
Intercropping where there is no reduction in density of any crop.
Term
Adventitious roots
Definition
A primary tissue. Produced by the apical meristem.
Term
Aesthetics
Definition
A benefit of multispecies cropping. Humansa and other animals benefiting from improved environmental qualities like shade and visual beauty.
Term
Agricultural use
Definition
A practical classification system that groups plants based on what humans use them for.
Term
Agro-ecological zone (AEZ)
Definition
Regions of the world based on what can be cultivated. The goal is to have MVs produced for every AEZ, but this is not yet completed. Sub-Saharan Africa and Latin America are missing.
Term
Agroclimate
Definition
The climate basis for crop adaptation.
Term
Agroecosystem
Definition
A natural ecosystem that has been modified by humans to allow for the production of the 4 Fs. Inputs and outputs of energy and nutrients are changed. Social and economic issues become a factor.
Term
Agroforestry
Definition
Intercropping with trees. A method of improving soil fertility. Used in early agricultural systems. Brings leached nutrients to the surface as a leaf litter.
Term
Agronomical product
Definition
Marketed dry. Water is removed.
Term
Agronomy
Definition
Concentrates on bio-physical functioning, assuming field homogeneity. Used succesfully in monocropping systems, but needs to be adapted to work for multispecies systems.
Term
Air density
Definition
Goes down as you get hgher up in altitude.
Term
Air movement
Definition
Can increase transpiration. Wind makes a plant grow stalkier. Protected agriculture prevents against this.
Term
Alfalfa
Definition

aka "The King of Forages"

Legume forage crop. An autopolypliod. Perennial: lasts 2 to 3 years, cut 3 to 5 times a year. Grown in rotation with corn. 18% protein. The crown and root survive the winter. If it is weak going into winter, surival will be poor. Ther is a critical harvest period in the fall. Ideal harvest stage is just before flowering.

Term
Alkali disease
Definition

aka Blind staggers

A disease in grazing animals. Caused by eating plants that have taken up selenium.

Term
Alkaline
Definition
Has a higher pH.
Term
Allelopathy
Definition
A form of weed supression. Inhibition of growth by a chemical compound in the soil from neighboring plants. Some tree species have allelopathic effects on crops.
Term
Alley intercropping
Definition

aka Row agroforestry

Crops planted between rows of trees. The tree may benefit from the crop, or the crop benefiting from the trees. Partially overcomes the mechanism barrier of multispecies cropping.

Term
Allopolyploid
Definition
A form of polyploidy. The chromosomes repeated are not the same. The crhomosomes do not pair up with each other. Happens when the chromosomes in an autopolyploid become divergent.
Term
Alphonse de Candolle
Definition
A Swiss botanist who studied the origin of crop species in 1885. Found that crops originate from the place in the world where there are wild versions of it.
Term
Aluminum (Al)
Definition
A beneficial element. In acidic soil it becomes toxic to plants. Plants are stunted and root development is impared. High aluminum concentrations interfere with phosphorus uptake, causing P deficiency symptoms.
Term
Amino acid
Definition
The building block of protein. There are 8 essntial amino acids, 20 total.
Term
Ammonium
Definition

NH4+

An ion form of N available to plants. A mobile element.

Term
Ammonium nitrate
Definition

NH4NO3

A mineral salt. When in the water it ionizes into ammonium and nitrate.

Term
Andean bean domsetication
Definition
Beans had vicarious domestication. In the Andes, kidney and green beans were domesticated.
Term
Aneroid barometer
Definition
A barometer that does not contain mercury.
Term
Angiosperm
Definition

aka Magnoliphyta

Flowering plants. A division in the kingdom Plantae. There are about 500 thousand species. Most crops belong to this group. Divided into dicots and monocots.

Term
Animal-drawn cultivation
Definition

3000 BC.

Used the ard, Saltus/Ager systems, and two-field rotations. Animals were slaughtered in the fall due to limited feed storage. Land was not well prepared or fertilized. Low productivity.

Term
Anion
Definition
A negatively charged ion.
Term
Annual
Definition
A lifecycle classification of vegetables. A plant that lives for one ear. Put all their energy into reproductive growth. Require re-establishment every year. Include lettuce, cucumbers, tomatoes, sweet corn, peas, beans, potatoes, and peppers.
Term
Anther
Definition
The floral organ where microgametophytes (pollen grains) are made.
Term
Antipodal cells
Definition
Three haploid cells created by the megasporocyte in the ovule. They stay near the chalazal end.
Term
Aphelion
Definition
The day that the earth is farthest from the sun. July 4.
Term
Apical meristem
Definition
Primary meristems. Includes the shoot and root meristems. The only meristems in an embryo.
Term
Apoplasm
Definition
The cell walls and intercellular spaces of the root. Water can enter these spaces, but cannot enter the xylem because it is blocked by the Casparian strip.
Term
Aquatic rice system
Definition
A method of improving soil fertility. Blue-green algae, azolla, and free-living rhizospheric organisms fix nitrogen in the water.
Term
Arable land
Definition
2 blilion hectares of it on Earth. 1.5 billion is used for agriculture. 10% of Canada's total land area is arable land.
Term
Ard
Definition

aka Scratch plow

Used 3000 BC. An animal-drawn tool. A single spike that is dragged through soil. Pulled with a neck yoke system.

Term
Associated biodiversity
Definition
The variety of species that are unintentionally included in an agroecosystem. Soil flora and fauna, herbivores, carnivores, decomposers.
Term
ATP
Definition
An energy-containing compound created from sugars in respiration. A primary compound. Phosphorus is an ingredient in making it.
Term
Australopithecus afarensis
Definition
An early ancestor of humans. Lived 4 million years ago Had upright posture and could manipulate objects.
Term
Authority
Definition

The third name that is sometimes included in a binomical system of nomenclature name. Tells you who classified that species.

Example: L stands for Linnaeus.

Term
Autopolyploid
Definition
A form of polyploidy. Formed from genomes duplicated within the species. The same set of chromosomes is repeated. The matching chromosomes pair with each other. Includes alfalfa, sour cherries, cultivated oats, and potatoes. Produces showier flowers.
Term
Autotroph
Definition
Synthesizes their own food reuirements using oxidized materials. Plants use plastids such as chloroplasts to reduce organic biomolecules.
Term
Avogadro's number
Definition

The number equal to a mole.

6.02e23

Term
Axillary bud
Definition
A shoot apical meristem apex surrounded by leaf primordia. Can form a branch, leaf, or reproductive inflorescense.
Term
Bambara bean
Definition
A pulse crop.
Term
Barley
Definition

Hordeum vulgare

A cereal crop or forage crop. Found in annual pastures. Requires 200 mm + of rainfall. Tolerant of heat and cold. Resistant to salinity. Has devleopmental plasticity. Yieldes 0.6 - 3 tonnes/ha.

Term
Barometer
Definition
A device that measures air pressure. Galileo invented one that used mercury.
Term
Basal intercalary meristem
Definition
The lowest intercalary meristem monocot.
Term
Base temperature
Definition
The lowest temperature at which a plant can grow. Different for different plants. In CHU, a 10ºC max and a 4.4ºC min results in 0 CHU.
Term
Beans
Definition
A pulse crop. A Fabaceae horticultural crop. An annual. Direct seeded. Self-pollinated. Interediate-rooted.
Term
Beneficial element
Definition
An element that doesn't reach the criteria for essentiality, but is beneficial to the plant.
Term
Biennial
Definition

A lifecycle classification of vegetables. Plants require two years to complete the reproductive cycle. First year, they form from a rosette, the second year they have bolting. Without the cold period of <10ºC for at least 10 days, bolting doesn't occur. This requirement may be bred out of a plant.

Beets, cabbage, Brussel sprouts, carrots, celery, onions, parsnips, Cole crops, horseradish, and many weeds.

Term
Binomial system of nomenclature
Definition
Used in scientific classification systems. Every species has a species name, its genus, and specific epithet. May also include an authority. Based on the ICBN.
Term
Binucleate cell
Definition
A diploid cell with two nucleuses created by the microsporocyte in the ovule. Stays near the chalazal end.
Term
Biodiesel
Definition
An alternative to diesel. Made from any oil or fat. Made  into FAMEs which can be used in any diesel engine. Makes use of waste fats (spent fryer oil, meat processing fat waste).
Term
Biodiversity
Definition
High genetic diversity. Species performing multiple ecosystem functions. Higher biomass production, nutrient retention, and reduced risk of invaasion of pests and diseases.
Term
Biodiversity conservation
Definition
A benefit of multispecies cropping. A larger range of wild species.
Term
Biological clock
Definition
How plants sense photoperiod. A set of genes and proteins creating a transcriptional-translational negative feedback loop. Responds to phytochrome, crytochrome, and temperature changes.
Term
Biological yield
Definition
The total biomass produced by a crop.
Term
Biotic enironmental factors
Definition
Living organisms. Herbivores, other plants. Plants are non-motile, so they have to deal with these factors where they are.
Term
Birdsfoot trefoil
Definition
A legume forage crop. Found in establishe pastures.
Term
Bolting
Definition
Occurs in the second year of a biennial. A rapid elongation of a flowering shoot. Doesn't occur without a cold period.
Term
Boric acid
Definition

H3BO3

The form that boron is absorbed in. Not an ion.

Term
Boron (B)
Definition
A micronutrient essential mineral element. The only mineral element that is absorbed not as an ion. Absorbic boric acid. Certain levels of soil boron are toxic to some plants and beneficial to others. Can cause a direct toxic effect. Its cell function is as a component of cell walls in very small amounts. An immobile element.
Term
Branch
Definition
A primary tissue formed from the apical meristem.
Term
Bread wheat
Definition

aka Triticum aestevum

A cross between pasta wheat (teteraploid) and Triticum tauschii (diploid). Used to make bread. The interaction between the parent genes somehow created sticky protein that captures CO2 from yeast, making the bread able to be leavened. Important in Mediterranean areas.

Term
Broad bean
Definition
A pulse crop.
Term
Bromegrass
Definition
A grass forage crop. Found in established pastures.
Term
Buckwheat
Definition
A cereal crop.
Term
Bud dormancy
Definition
A cold period required by a meristem before it can grow. Restricts fruit and nut production to temperate regions.
Term
C3
Definition
Plants that cannot concentrate CO2 like a C4 plant can. Wheat, rye, triticale, barley, oats, and rice. Has a lower photosynthetic response to increases in light.
Term
C4
Definition
Can concentrate CO2 in certain parts of the leaf, increasing yield. Corn, sorghum, millets. Has a higher photosynthetic response to increases in light.
Term
Cadmium (Cd)
Definition
A heavy metal.
Term
Calcium (Ca)
Definition
A macronutrient essential mineral element. Absorbed as Ca2+. Its cell function is as a component of cell walls, and as a signal transduction pathway. Deficiency causes malformed plants. An immobile element. Deficiencies more common in fruit crops.
Term
Calories
Definition
When spelled with a big C it means 1000 times as many as when spelled with a little c. The world requires 6.5e9 Calories a day, yet we produce 3 times as much. The rest goes to waste.
Term
CAM
Definition

Plants that take up CO2 in the nighttime so that during the day photosynthesis can occur with stomates closed, reducing transpiration completely.

Cacti.

Term
Canary seed
Definition
A cereal crop.
Term
Canola
Definition

aka Brassica napus

CANadian Oil Low Acid. A Canadian-invented oilseed derived from rapeseed. Lower in erucic acid and glucosinolates. Canada produces 11% of the world's canola, 99.9% of this production is in Western Canada. Canola is 42% oil.

Term
Canopy
Definition
Layers of leaves competing for light. Leaves at the top get more radiation. Leaves at the bottom are only exposed when radiation levels are very high.
Term
Canopy architecture
Definition
The arrangement of leaves in a canopy. More horizontal leaves intercept more light on top and less on the bottom. More vertical leaves have it more spread out.
Term
Canopy extinction coefficient (k)
Definition
A measure of the angle of the leaves in canopy architecture. 1 means perfectly horizontal. 0 means perfectly vertical. Has an effect on LAI and solar radiation interception. Plants can be bred to have different k values.
Term
Carbohydrates
Definition
A reduced organic biomolecule created by plants out of oxidized materials. A primary compound. Humans need 300 to 400 grams a day.
Term
Carbon (C)
Definition
An essential non-mineral element. Absorbed as CO2.
Term
Carbon cycle
Definition
Managed by rotations, perennials, cover crops, tillage, manure, and compost.
Term
Carbon dioxide
Definition

CO2

A plants #1 most needed nutrient. Enters through the stomates.

Term
Carbon sequestering
Definition
A benefit of multispecies cropping. Enhances soil carbon content. Contributes to climate change mitigation.
Term
Carotenoid
Definition
An antioxidant. Precursor to vitamin A. Needed in humans to produce eye pigment and T-cells. Found in plants and some meat and dairy products. Deficiency can lead to infant mortality. It determines the colour in sweet corn.
Term
Casparian strip
Definition
A waterproof layer in the endodermis that prevents water from entering the xylem through the apoplasm.
Term
Cassava
Definition

Manihot esculenta

aka Yuca

A root crop. Originated in Brazil. Grown in an 18 month cycle. A subsistence crop in Africa, Oceania, South America, and the Caribbean. Requires 500 mm of rainfall, but optimally 1000 mm - 2000 mm. Includes bitter and sweet cassava. The longer they are left in the ground, the more woody the roots get. Fresh roots are 70% moisture and very bulky and hard to transport. Fresh roots can be stored for only 3 - 4 days before they start to rot. Raw root contains cyanide which is toxic and very unpalatable. Must be processed before consumption. May be intercropped. Cassava is used for flour, confectionaries, feed, ethanol, processed foods, textiles, pharmaceuticals, paper industry, or in traditional foods.

Term
Castor
Definition
An oil seed crop.
Term
Cation
Definition
A positively charged ion
Term
Cellular function
Definition
The purpose of an element in the cell.
Term
Cellulose walls
Definition
All plant cells have a rigid wall encasing them, permanently sticking them together. Restricts growth to accretional growth It can be used to produce ethanol, but there still needs to be scientific research.
Term
Cereal crop
Definition
Provide 80% of the world's calories. Also used as feed. Low in lysine, but high in methionine. C3s. All are monocots. All are grasses except quinoa. Straw is used as forage and livestock beding. Grown in temperate climates. Main ones are wheat, corn, and rice, alos includes barley, oats, and rye. There are spring and winter varieties. Early planting and early harvset in comparison to corn and soybeans. In some cases there can be two crops per season. Population, winter survival, fertility, and photosynthesis are important.
Term
Cereal/legume intercropping
Definition
Planting a cereal and a legume together in a multispecies cropping system. Cereal gets more nitrogen and sulphur. The cereal crop has more competitive roots.
Term
CGIAR
Definition
Consultative Group for International Agricultural Research. A group of IARCs with an annual budget of $340 million and 8500 scientists.
Term
Chalazal
Definition
The side of the ovule opposite from the micropyle.
Term
Chemical effect
Definition
A form of pest/disese suppression in multispecies cropping systems. The crop mixture creates substances with negative effects on pests.
Term
Chick pea
Definition

Cicer arietinum.

A pulse crop. Includes kabuli and desi. Requires 600 mm - 1000 mm of rainfall. Germinates at 10ºC to 35ºC. Optimum temperature is 19ºC - 28ºC. Yields up to 0.7 - 1.17 tonnes/ha.

Term
Chilling injury
Definition
Damage done to a crop due to temperature below its optimal range of temperatures. Can be avoided by planting after the frost date, transplanting, putting in tunels or row covers, using sprinker irrigation, wind machines, or dark coloured mulches.
Term
Chisel plow
Definition
A plow that leaves some residues on the surface.
Term
Chloride effect
Definition
An indirect toxic effect caused by high soil salinity. A major problem in many areas of the world.
Term
Chlorine (Cl)
Definition
A micronutrient essential mineral element. Absorbed as Cl-. It can cause chloride effect. A mobil element.
Term
Chlorophyll
Definition
A pigment in photosynthetically viable tissues that absorbs PAR in photosynthesis. Found in chloroplasts. Has two forms: A, and B. Absorbs red and blue radiation, reflecting green, causing it to appear green. Nitrogen and magnesium are ingredients for making it.
Term
Chloroplast
Definition
A plastid that contains pigments such as chlorophyll and performs photosynthesis.
Term
Chlorosis
Definition
Yellowing of leaves. A deficiency symptom.
Term
CIMMYT
Definition

International Center for Wheat and Maize Improvement.

In Mexico. Belongs to CGIAR.

Term
Circle of illumination
Definition
The half of the earth that is experiencing sunlight.
Term
Class
Definition
The taxon below division. Contains subclass. Has names ending with -ae or -opsida.
Term
Classification
Definition
The grouping of plants into groups with other plants with similar characteristics. Based on practical classification systems.
Term
Cleistogamy
Definition
Self-fertilization within a closed flower bud. A form of self-pollination.
Term
Climate
Definition
Long-term, large-region weather patterns. A factor in selecting sites for vegetable cropping systems. Temperature must correspond to the crop's cool/warm season classification. Water must provide 25 mm per wee to plants (depending on soil type and crop rooting depth).
Term
Cloudiness
Definition
An aspect of weather and climate.
Term
CO2 compensation point
Definition
The CO2 levels where CO2 uptake is zero.
Term
CO2 Exchange Rate (CER)
Definition
CO2 fixed through photosynthesis minus CO2 lost through respiration. 90% of a plants dry weight is carbon fixed from the air.
Term
CO2 saturation point
Definition
The CO2 levesl where any increase in CO2 concentration in the air results in no increase in CO2 uptake.
Term
CO2 supplementation
Definition
Increasing CO2 levels in a greenhouse. Stimulates faster growth.
Term
Cobalt (Co)
Definition
A beneficial element. Essential for legumes.
Term
Cocoa agroforestry
Definition
Planting cocoa underneath shady trees. Reduces insects, but increases pod rot.
Term
Coconut
Definition
An oil seed crop.
Term
Coffee
Definition
A flavour/pharmaceutical crop.
Term
Coffee agroforestry
Definition
Growing coffee underneat shady trees. Results in a more balanced filling of berries, yielding higher quality product.
Term
Cold hardiness
Definition
The ability of a plant to survive freezing temperatures. Species that lack cold hardiness may die from frost.
Term
Columbian exchange
Definition
When Europeans first came to the Americas, Old World crops were brought to the Americas and American crops brought to the Old World.
Term
Commercial fertilizer
Definition
Has 3 numbers in its name, indicatin the weight percentage of nitrogen, phosphorus, and potassium, respectively.
Term
Compaction
Definition
The squashing of soil, squeezing away all the pore space. Reduces soil moisture. Slows drainage and root growth.
Term
Competition
Definition
When one plant exerts a negative effect on another plant. Can be a form of weed suppression. There is more competition in high-resource environments. The less competition between crop species, the better a multispecies cropping system is. There is competition for light, water, and nutrients.
Term
Complete fertilizer
Definition
Fertilizer that contains all the essential mineral elements.
Term
Complex agroforestry
Definition
A wide variety of tree and herbaceous crops mixed intercropped.
Term
Concentration
Definition
The amount of a substance in a solution. Measured in ppm or M.
Term
Conduction
Definition
A mechanism of heat transfer. Heat travels through immobile molecules, such as through a solid. Some materials are better conductors than others.
Term
Conservation agriculture
Definition
Permanent ground cover, reducing erosion. Minimum tillage, cover crop use. Deep-rooted perennials complement water and nutrient use. Agroforestry.
Term
Convection
Definition
A mechanism of heat transfer. Heat travels through moving molecules, such as through a fluid (gas or liquid).
Term
Convention of Biological Diversity
Definition
A convention created in 1992. Goals are to conserve biological diversity, have sustainable use of its components, and fair and equitable sharing of the benefits.
Term
Conversion factor
Definition
The dry weight of feed given to an animal divided by the dry weight of the animal. Different animals have different conversion factors. It takes 8kg of grain to make 1kg of beef.
Term
Conversion loss
Definition
A food loss. When we feed livestock, a good portion of the mass is lost due to a less than one conversion factor.
Term
Copper (Cu)
Definition
A micronutrient essential mineral element. Absorbed as Cu2+. Its cell function is as a component of photosynthetic electron transport chain. Deficiency can occur in acidic organic soils, and leached sandy soils. Causes leaf distortion and cracked leaf edges.
Term
Cork cambium
Definition
A lateral meristem that makes bark in woody plants.
Term
Corn
Definition

aka Maize

aka Zea mays L.

A major cereal and forage crop. Day-neutral. Originated from teosinte in Mesoamerica 5000 years ago. A C4 crop. Requires 1000 + mm of water. Has a multitude of uses in food industry. A variety of types of corn. Grown in a wide range of latitudes, including temperate climates. Often cultivated with beans and squash. High yielding. Produces a lot of residue, which affects subsequent crops. Frost sensitive. Needs high temperature an low moisture. The area of land growing corn in Ontario is rising. Management enables rapid, uniform emergence and early silking. Non-limiting fertility. High plant water availability is good (root growth not restricted). Weed control. Nitrogen fertilization is an issue (nitrous oxide emissions, leaching, manure, covre crops, genetics). There are drought tolerant hybrids (only reduce losses). Irrigation may have vlue. Found in many food products (corn starch, HFCS, animal feed). Used in ethanol and plastics production. Yields are about 140 - 160 bu/ac. In developing countries yields are 30 - 40 bu/ac due to crop failure. Corn is 10% protein, but high in energy.

Term
Corn-soybean rotation
Definition
The lowest yield and worst fertility of rotations. Moisture and drought intolerant. Highest greenhouse gas emissions. The most common rotation in Ontario because it is the most profitable.
Term
Cotton
Definition

An oil seed crop. The most important fibre crop. Its seeds contain gossypol. Rain-fed or irrigated systems. Small and large farms. Includes Old World and New World species. Potentially a perennial but grown as an annual. Naturally indeterminate. Yields 1 - 4 tonnes/ha. Fibre is 20% - 40% of the weiht. Seeds produce cottonseed oil and cottonseed cake (used in animal feed). Optimum temperature is 27ºC. Drought tolerant; has a taproot. Slow initial growth. Harvested mechanically or by hand. Boll development stages are pinhead square, match-head square, square growth midpoint, candle, white, bloom, and boll development. The plant has a long straight vegetative bracnh, and a zig-zagged fruiting branch, each one is 3/8 of a turn around the stem from the branch below it. Flowers are self-pollinating.

Susceptible to weeds, pests, and disease because it has different parts going through different developmental stages at the same time.. Extremely wide range of insect species includin monophageous, oligophageous, and polyphageous species. Controlled with insecticides, destruction of remains, weed control, and crop rotation. Cotton accounts for 11% of all pesticide sales and 25% of insecticide sales. S

Term
Cotton gin
Definition
A machine that separates the lint and from the seed in cotton. Cleans ay debris.
Term
Cotyledon
Definition
Embryonic leaves. Monocots have one. Dicots have two. In dicots they absorb the endosperm and become the main food source for the embryo.
Term
Cover crop
Definition

aka Green manure

A crop that benefits soil and other crops, but itself is not harvested. Reduces soil moisture. Benefits soil erosion, organic matter, soil structure, nitrogen, leaching, weed suppression, reduced pest population, soil structure, and can be a pasture crop. Oilseed radish, oats, medic, rye. Found in annual pastures.

Term
Cow pea
Definition

Vigna unguiculata L.

Originated in Western Africa. A pulse crop. An annual. There are bushy, erect, prostrate, and creeping varieties. Plant is 30 cm - 60 cm tall. Pods are 8 cm - 30 cm long and grow in pairs. 8 - 20 peas per pod. Peas can be grey, brown, red, or light coloured. Regional preferences for colour. A legume; fixes 240 kg N/ha. Crops are significantly improved with the use of pesticides.

Term
Critical day length
Definition
The day length that changes whether a photoperiodic plant will flower or not. Actually it is the night length that is critical.
Term
Criteria for essentially
Definition

The criteria for an element to be considered essential to a plant. 

1. Plant unable to complete lifecycle without it.

2. No other element can substitute it.

3. Directly involved in plant function.

Term
Crop Growth Rate (CGR)
Definition
Measured in weight of dry matter per unit of land per time period.
Term
Crop Heat Units (CHU)
Definition
A unit to measure the amount of heat a plant is exposed to over a day or a year. Geographical regions are exposed to diferent accumulated CHU. Developed based on data from the period between 1971 and 2000. A factor in shoosing sites for fruit cropping systems.
Term
Cropping system
Definition
A site where a plant is grown, its production/growing system, harvesting, postharvest handling, and marketing. The cropping pattern and production technique used on a farm. The yearly sequence and spatial arrangement of crops and fallow. Takes into account the residue, fertility, cover crops, disease, pests, soil moisture, crop variety, weeds, rotation, and tillage. Effects profit, sustainability, productivity, and externalities. Constrained by weather, climate, soil characteristics, capability and availability of technologies, markets, economics, household requirements, regulations, and social factors. A way of classifying vegetable and fruit crops. For vegetables it includes field-grown for processing, field-grown for fresh market, and greenhouse for fresh market. For fruit it includes berry cropping and tree fruit cropping.
Term
Cross-pollination
Definition
When pollen from one plant lands on another plant's stigma. A pollination classification of vegetable crops. Wind pollinatin or insect pollinated (which requires bees).
Term
Crown
Definition
Where the nodes are very close together beneath the soil level in grasses.
Term
Crytochrome
Definition
A photoreceptor that causes phototropism.
Term
Cumulative growth
Definition
The level of growth achieved. When graphed over time for annual determinate crops, makes a sigmoid growth curve.
Term
Cut and carry
Definition
A method of improving soil fertility. Used in early agricultural systems after the invention of the scythe. Feed is harvested and transported to stables, then manure is spread on fields.
Term
Daily CHU
Definition
The average daily maximum and temperature and minimum temperature.
Term
Day-neutral plant
Definition
A photoperiod classification of vegetables. Neither short-day nor long-day. Flowers independently from day length. INcludes cucurbits, Solanaceous crops, legumes, and sweet corn.
Term
Deep-water rice
Definition

aka Floating rice

Rice that can grow in water up to 5 meters deep in flooded conditions. If the waters recede, the plant will fall over.

Term
Deficiency symptoms
Definition
Problems occuring in a plant when there is not enough of a nutrient.
Term
Density Equivalent Ratio (DER)
Definition
Doesn't take into account for crop interactions.
Term
Dent corn
Definition

aka Zea mays indentata

The main corn variety used as animal feed. Composed of hard starch with a soft arch in the crown. Shrinks when dried, causing a dent.

Term
Dermal
Definition
A tissue system. Includes the epidermis and cork.
Term
Destructive biota
Definition
Species that harm the crop. Weeds, pests, pathogens.
Term
Determinate
Definition
Grows to a certain size and then stops. Leaves, flowers, fruits. Determinate species have stems that end with floral buds.
Term
Development
Definition
The production, differentiation, expansion, and senescence of phytomers.
Term
Developmental plasticity
Definition
Because plants have only 3 organs, they take on a huge range of different morphologies to adapt to their environments.
Term
Dicot
Definition

aka Magnoliopsida

aka Dicotyledneae

One of the divisions of angiosperms. Seeds contain two cotyledons. Vascular bundles are arranged in a cylinder of the stem. Can be woody. Branched leaf veins. Flower petals are in multiples of four or five. Vegetative apical meristem is above soil level. Has only apical meristems in the primary plant body.

Term
Differentiation
Definition
Changes that occur in cells to undergo specific functions in the plant.
Term
Dilution effect
Definition
A form of pest/disease suppression in multispecies cropping systems. The mixture of crops results in each crop being less dense, making it harder for pests to locate host plants.
Term
Dimorphic life cycle
Definition
A life cycle with two distinct generations: sporophyte and gametophyte. There is alteration of these generations.
Term
Diploid
Definition
Having two copies of each gene and chromosome. Many wild plants. All animals.
Term
Direct toxicity
Definition
A toxicity effect where the element itself influence the plant.
Term
Dispersal from domestication centre
Definition
The second genetic bottleneck in domestic crops. Only a small sample of the seeds were brought with early traders.
Term
Division
Definition

aka Phylum

The taxin under kingdom. Contains class. Has names ending with -phyta. In animal classification it is called a phylum.

Term
DNA
Definition
A reduced organic biomolecule created by plants out of oxidized materials. A primary compound. Nitrogen is an ingredient in making it.
Term
Dolomitic limestone
Definition
Raises the magnesium levels and pH of the soil.
Term
Domestication
Definition

Because the genes for domestication syndrome are fairly condensed on the genome, it would be possible domesticate a crop within 10 to 100 years if someone was trying. However, ancient people were not actively trying to domesticate, and used agriculture only occasionally, decreasing the selection pressure. In reality it took up to 1000 years. Domestication is the first genetic bottleneck in domestic crops; only a small number of mutants are selected as the gene pool.

A change in plant morphology. Reduced seed shattering, overcoming of seed dormancy, optimum growth habit and harvest index, gigantism, and resistance to pests and disease.

Term
Domestication syndrome
Definition
The changes in a plant when it is domesticated. Regularly tilled soils selects for annual plants with rapid growth and abundant seed production (weeds and crops alike). Disposal of human wastes and fires selected for better fertilizer response. Seed shattering disapears. Seeds germinate at once in favourable conditions. Growth habit is more compact and less viney. Harvest index is increased. Gigantism in the harvested part. Toxic compounds reduced and diseases. These traits exist in a small area of the genome.
Term
Dormancy
Definition
A state of not growing. Plants enter it when temperatures go outsied of the optimal range of temperatures. Seeds do it.
Term
Dormant buds
Definition
Stem meristems that are not growing.
Term
Double fertilizations
Definition
One sperm cell from the pollen combines with the egg to produce the zygote. The other sperm cell combines with the binucleate cell to produce the primary endosperm nucleus.
Term
Double sequential cropping
Definition
Sequential cropping with two species.
Term
Drought stress
Definition
Stress caused by low water availability. It has different effects on a crop when implemented during different stages of development.
Term
Dry mill
Definition
A mill where ethanol is made. Not as versatile as a wet mill. The by-products are dry distill grains, and CO2.
Term
Dry weight
Definition
The weight of a plant after being dried for 2+ days at 70ºC to 80ºC. Lacks all the water weight. Used for agronomical products.
Term
Ear
Definition
The female reproductive part of a corn plant. A lateral vegetative meristem becomes a reproductive meristem.
Term
Early Green Revolution
Definition
Between 1981 and 2000. Production increased, prices declined. Amount of agricultural land hit a plateau.
Term
Ebla and Mari
Definition
Two of the earliest cities ever. In the Mesopotamia area between the Tigris River and Euphrates River. A surplus in foods allowed for time devoted to crafts, religion, military, trade, and administration.
Term
Economic biological mass
Definition
The weight of the harvested part of the plant.
Term
Economic yield
Definition
The total biomass partitioned as the harvest.
Term
Egg
Definition
A haploid cell created by the megasporocyte in the ovule. Stays near the micropyle end.
Term
Einkorn wheat
Definition

aka Triticum monococcum

The first species of wheat to be domesticated. The lower yielding branch of wheat species. Used today for animal feed. Was once a staple grain.

Term
Electrical conductivity (EC)
Definition
A measure of total salinity. Measured in mmho/ch. Can reach levels where the availability of roots to take up water decreases.
Term
Electromagnetic specturm
Definition
The spectrum of different wavelengths of light. Goes from gamma rays (the smallest wavelengths) to radio waves (the largest wavelengths).
Term
Electromagnetic wave theory
Definition

A theory that light moves through space as a wave. It moves at the speed of light (c). Because it is a wave, light has a frequency (γ) and wavelength (λ). 

c = γλ

Term
Embolism
Definition
An air bubble in the xylem. Occurs when the stem is cut.
Term
Embryo
Definition
Diploid. Formed from the zygote. Has a different genome from the seed coat and fruit surrounding it in the seed.
Term
Embryogenesis
Definition
The devleopment of seeds.
Term
Embryonic vegetative meristem
Definition
Meristem that forms seeds. Stays growing in a plant for its whole life.
Term
Emmer wheat
Definition

aka Hulled-grain wheat

aka Triticum dicoccum

A cross of two diploid species, AA and BB, creating a tetraploid AABB.

Term
Electromagnetic radiation (EMR)
Definition
Light. Two theories as to what it is: electromagnetic wave theory, and quantum theory. It effects photosynthesis, plant development, and plant water use. Attributes: quality, intensity, and duration.
Term
Endodermis
Definition
The layer of cells surrounding the xylem and phloem. Contains the Casparian strip.
Term
Endosperm
Definition
A triploid structure formed from the primary endosperm nucleus. In monocots it is the main food source for the embryo, as well as the main source of food for humans (wheat, rice, corn, other grains). In dicots it is absorbed into the cotyledons.
Term
Energy-containing compounds
Definition
What chloroplasts make using light energy. ATP and NADPH.
Term
Energy ratio (ER)
Definition
A calculation of cropping system efficiency. Energy outputs of a cropping system divided by energy input (not including energy from the sun). Inputs include labour, fuel, electricity, seeds, fertilizers, pesticides, machinery, and water. In these terms, the most efficient system is slash-and-burn systems, and the worst are heated winter greenhouses.
Term
Energy use efficiency
Definition
The efficiency of a plant's use of light. In theory the maximum is 5%, but in a field it is actually 0.5% due to biotic and abiotic stresses to the plant.
Term
Equator
Definition

A line around the earth where the sun's rays shine on a 90º angle on the equinoxes, March 20 and September 20.

 

Term
Equidistant row spacing
Definition
A type of row spacing where distance between the seeds is the same as the distance between rows, but in a grid pattern. In terms of solar radiation interception, better than traditional, but not as good as iosmetric.
Term
Equinox
Definition

March 20 and September 20. The days in the northern hemisphere that has an exactly 12 hour photoperiod. The sun's rays hit the equator at a 90º angle.

 

Term
Equisetophyta
Definition
A division of the kingdom Plantae. Horse-tails.
Term
Erucic acid (22:1)
Definition
A fatty acid bred out of rapeseed to create canola. Was once believed to damage cardic muscles.
Term
Essential mineral elements
Definition

aka Mineral ions. 

Elements acquired through the soil solution as ions. Meet the  three criteria for essentiality. Nitrogen, phosporius, potassium, sulphur, magnesium, caclium, chlorine, iron, boron, manganese, zinc, copper, molybdenum, and nickel. Grouped into macronutrients and micronutrients.

Term
Essential-non mineral elements
Definition
90% - 95% of dry matter of the plant. Essential to photosynthesis. Aquired through CO2, O2, and water, not as ions. Carbon, hydrogen, and oxygen.
Term
Ethanol
Definition
Produced from sugars and starch or cellulose. Cellulose is more efficient. A way to make plant biomass into fuel. It can replace gasoline. Made in wet mills or dry mills. In North America corn is mainly used, and in South America sugar can is used, but any plant can be used. There are some crops that are used only for ethanol production. There is some debate as to if this type of energy production is worth it; is more energy put in than comes out? If you count energy from waste products, the balance is positive.
Term
Evapotranspiration (ET)
Definition
The combined water loss from evaporation from the soil an plant transpiration. When ET is greater than precipitation, there is drought stress.
Term
Evolution of agricultural systems
Definition
Symbiotic relationship between plants and humans. Evolution of agriculture systems was slow and gradual, efected by climate, physiography, soils, flora, and fauna. A matter of breeding, plant nutrition, and tillage mechanisms. Using fire to clear areas. Sowing seeds. Grinding grasses to produce flour. Making alcohol. Using legumes, tubers, and animals.
Term
Ex situ conservation program
Definition

aka Off-site program

Gene banks where thousands of seeds are kept. Botanic gardens with live specimens. Sterile culture flasks of plant matter.

Term
Exine
Definition
The outer wall of a pollen grain.
Term
Externality
Definition

An input brought into a cropping system from outside

or

When an action in a system causes an outside effect. Can be negative (pollution) or positive (bird habitat).

Term
Facilitation
Definition
When one plant exerts a positive effect on another plant. More facilitation in harsher environments. The more facilitation, the better a multispecies cropping system is. The plants occupy different ecological niches.
Term
Fallow
Definition
Not actively growing a crop on the land. Nothing grows. Uses less water.
Term
FAME
Definition

Fatty Acid Methyl Ester

Three fatty acids in a triglycerol, but separated from one another. Used as a biodiesel.

Term
Family
Definition
The taxon under order. Contains genus.
Term
Far red light (FR)
Definition
Light with a frequency of 730 nm.
Term
Feed
Definition
One of the things plants provide for us. Many feed crops are also food crops, especially cereal crops. Silage, stover, and forage can be used as feed for ruminants. Protein meal by-product from oil seeds can be used, especially swine and poultry.
Term
Fertile Crescent
Definition
Turkey, Lebanon, Israel, Jordan, Syria, Iraq, and Iran. Wheat was domesticated here.
Term
Fibre
Definition
One of the things plants provide for us.
Term
Fibre crop
Definition
A crop grown for its cellulose fibre. The fibres are extracted and used to make textiles, rope, and many other things.
Term
First modern agricultural revolution
Definition

1500 AD

Animal-drawn cultivation using the plow without fallowing. Used rotation of cereals with fodder crops or seeded pastures. Complex rotations, including the Norfolk 4 course rotation. Increased animal populations. Increased food supply. Improvement on the plough lead to improved land preparation.

Term
Flavours
Definition
One of the things plants provide for us.
Term
Flax
Definition
A fibre crop and oilseed produced in Canada.
Term
Flaxseed
Definition
An oil seed crop.
Term
Flint corn
Definition

aka Zea mays indurata

A variety of corn. Kernels are mainly hard starch, but do not dent when dried.

Term
Floral intitiation
Definition
The stage in crop phenology after which leaf number is fixed. Effects yield greatly.
Term
Floral meristem
Definition
A type of vegetative meristem. Produces reproductive floral organs. Can be determinate or indeterminate.
Term
Flour corn
Definition

aka Soft corn

aka Zea mays amylacea 

A variety of corn with very little hard starch. Can easily be ground into flour.

Term
Flower
Definition
The reproductive structure. A primary tissue. Produced by the apical meristem.
Term
Flowering
Definition
The formation of reproductive structures.
Term
Fonio
Definition
A cereal crop.
Term
Food
Definition
One of the things plants provide for us.
Term
Food loss
Definition
We only use a third of the food we grow. These are due to waste, conversion losses, and non-food uses.
Term
Foot-candle (ft-c)
Definition
A unit of illuminance. Lumen per square foot.
Term
Forage
Definition
Crops for ruminant feed. Usually perennials. Can be direcltly grazed or in a cut-and-carry system. Grasses and legumes. Includes alfalfa, birdsfoot trefoil, red clover, white clover, alsike clover, sweet clover, bromegrass, timothy, corn, cereal crops, reed canarygrass, orchardgrass, perennial ryegrasses, tall fescue, meadow fescue, creeping red fescue, meadow foxtail, and Kentucky bluegrass. Must have grazing tolerance. Can be mechanically harvested or pasture grazed by livestock. Forage performance may be more important to livestock weight gain than livestock performance. Forage quality and energy spent on foraging are factors in weight gain.
Term
Fresh weight
Definition
The weight of the plant with the water still in it. Used for horticulturaly products. 80% - 85% of a healthy plant's freshweight is water.
Term
Fruit
Definition

A formation around a seed that aids in the seed's dispersal. Formed from the funiculus and ovary wall. Diploid. Has the same genome as the mother plant. Served as a dessert to be considered fruit.

A sector of Canadian horticulture that produces $750 million/year, mostly in Quebec. Can be grown between 30 and 50 decrees latitude north or south. Requires dormant and active growth periods with sufficient chilling to overcome bud dormancy. Have different levels of cold hardiness. Pollination and fertilization are required to produce fruit. Only 80 of 2400 potential fruit species have been domesticated.

Term
Fuel
Definition
One of the things plants provide for us.
Term
Fun
Definition
One of the things plants provide for us.
Term
Funiculus
Definition
A stalk that holds up the ovule. After fertiliation develops into the fruit.
Term
Gametophyte
Definition
The gametophytic generation. Completely dependent on the sporophytic generation. Has male and female components, the microgametophyte and megagametophyte, respectively.
Term
Gene pool
Definition

GP1 = the species

GP2 = species that can be sucessfully crossed with GP1

GP3 = species that can be sucessfully crossed with GP1 with difficulty

GP4 = species that cannot be crossed with GP1

Term
Generative cell
Definition
A haploid cell in a pollen grain. Created by the microspore. At some point (either before or after the pollen is released, depending on species), it divides mitotically, creating two haploid sperm cells.
Term
Genetic erosion
Definition
Decrease in genetic diversity. Agriculture is speeding up genetic erosion. Results in modern varieties having a narrow gene pool. Limits the resources for breeding programs. Can be helped by conservation programs.
Term
Genus
Definition
The first name in the binomial system of nomenclature. Tells you the genus of the species. The taxon under family. Contains specific epithet. Has names ending with -ales.
Term
Gigantism
Definition
A symptom of domestication syndrome. The harvested part of the plant becomes huge and brightly coloured.
Term
Gleysol
Definition
A soil classification found in poorly drained clay soils.
Term
Glucosinolates
Definition
A chemical with a mustard-like taste. Bred out of rapeseed to create canola.
Term
Glume
Definition

aka Hull

A leaf-like structure on the outside of wheat grains. Needs to be removed from the grain (threshed) before eaten. Some varieties have thicker glumes than others.

Term
Gossypium arboreum
Definition
A diploid cotton species in Asia that produces spinnable fibres.
Term
Gossypium herbaceum
Definition
A diploid cotton species in Africa that produces spinnabel fibres.
Term
Gossypol
Definition
A chemical present in cotton seeds. It is toxic to monogastrics.
Term
Granoculture
Definition
12000 - 8000 years ago. Transition from husbandry from wild species to management of domestic species. Domestication of wheat, sheep, and goats. Blade tools. Settled farming communities.
Term
Green Revolution
Definition

1960 - 2000

International agricultural research centres, such as CGIAR and CIMMYT, collaborated to develop HYVs and MVs of many crops. Over 8000 were made in 11 crops. Huge increases in crop production. Beans and cassava MVs not developed untill later in the revolution. Decreased food prices. Without the Green Revolution, yields would be 2.4% higher in developed countries and 22% lower in developing countries. Average caloric intake would be 14% lower and the number of malnourished children 7% higher. Did not affect Sub-Saharan Africa. Caused long-term soil degradation, chemical pollution, aquifer depletion, soil salinity, biodiversity, environmental, and socioeconomic impacts. May be unsustainable.

Term
Greenhouse effect
Definition
Shortwave radiation comes from the sun and goes through the atmosphere. It is reflected as long wave heat radiation which is absorbed by greenhouse gasses in the atmosphre, heating up the atmosphere.
Term
Greenhouse gas
Definition
Gasses that contribute to the greenhouse effect. Water vapour, CO2, nitrous oxide, and methane.
Term
Greenhouse system
Definition
In a greenhouse, plants have 3% efficient photosynthesis. It is so high because there is no stresses such as wind or pests, and growing season is extended.
Term
GRIP
Definition

Gross Revenue Insurance Program

Can effect what farmers will grow. Caused soybean production to go up.

Term
Ground
Definition
A tissue system. Includes cortex and mesophyll.
Term
Growth
Definition
Irreversible increase in plant size. Cell number goes up. Cell division occurs in the region of cell division of the meristems. In agronomical products, this is measured by dry weight. In horticultural products, this is measured by fresh weight. Can also be measured by length of stem, length of branches, length of roots, size of other organs, area of leaves, diameter of stem, or volume. Growth rate is directly correlated with amount of solar radiation intercepted, which is dependent on LAI.
Term
Growth habit
Definition
Wild plants compete with other plants for nutrients, light, and water. Growth habits reflect this (bushy, large-limbed, viney). Domestication syndrome makes plants more compact-sized. Vine plants become bush-like plants.
Term
Habitat effect
Definition
A form of pest/disease suppression in multispecies cropping systems. Contrasting plant architecture creates a new habitat for a pest predator, such as birds.
Term
Harvest index (HI)
Definition
The ratio between economic biological mass and total biological mass. Domestication syndrome makes the harvest index increase. Plants may be bred to improve harvest index.
Term
Heavy metals
Definition
Elements that accumulate in plants. May be benign to plants, but are toxic to animals including humans. Found in high concentrations in urban soils.
Term
Hemp
Definition
A fibre crop.
Term
Hempseed
Definition
An oil seed crop.
Term
Heterotroph
Definition
Have to seek out food and eat it. Animals. Some parts of plants, such as roots, are heterotrophic.
Term
Hexaploid
Definition
A form of polyploidy. Has six copies of every gene and chromosome.
Term
Holocene era
Definition
A period in earth's history 11700 years ago where weather became warmer, wetter, and there was more CO2. They know this from studing ice. Caused the origin of agriculture.
Term
Homo erectus
Definition
An early ancestor of humans. Lived 2 million years ago up to 400,000 years ago. Had a larger brain than Homo habilis. Had a body size similar to modern humans. Hunters and gatherers. Mastered fire 500,000 years ago. Migrated from Africa to Asia and Indonesia.
Term
Homo habilis
Definition
An early ancestor of humans. Lived 2.5 million years ago. Had an enlarged body and brain. Used stone tools.
Term
Hormones
Definition
A reduced organic biomolecule created by plants out of oxidized materials. A primary compound.
Term
Horticultural product
Definition
A plant produced that cannot be stored dry. Marketed fresh. Water is not removed.
Term
Humans
Definition

aka Homo sapiens

Originated in Africa 50,000 years ago. Killed all the Neanderthals. Had advanced tools (standardized sizes, variety of materials, multi-piece). Sewn clothing. Elaborate burial rituals. Created art in caves.

Term
Humus
Definition
Highly stable organic matter. Turns over every 1000 years.
Term
Hunter-gatherer
Definition
People who hunt and gather their food without use of agriculture. Were widespread 15,000 years ago. Had a wide range of diet. Used grinding tools and storage pits. Modern hunter-gatherers have extensive knolwedge handed down through generations on the animals and plants they hunt and gather. This lifestyle yields an abundant diet with relatively little work, however on arable land it can only support a tenth of the number of people the land could support using agriculture.
Term
Hybridization
Definition
Creating a cross with members of gene pool GP2 and GP3. When crops hybridize with wild progenitors, the hybrids either die out quickly. They can survive by back-crossing with either parent species. Some hybrids look just like the domestic crop but are actually weeds.
Term
Hydraulic systems
Definition

8000 BC - 4000 BC

A method of improving soil fertility found in early agricultural systems in Iraq and on the Nile. Annual floods bring water and fertile silts to cropland. Winter cultivation in permanent fields of wheat, barley, or millet / peas, lentils, or Egyptian clover rotations. Use of spate and basin, and the shadouf. These systems eventually failed due to salinization, waterlogging, and malaria.

Term
Hydrogen (H)
Definition
An essential non-mineral element. Absorbed as H2O.
Term
Hydroponics
Definition
Nutrient delivery not involving soil. Used in most greenhouses. Most use a root-zone substrate or liquid (if not, it is aeroponics). Hydroponic liquid 1% nutrients, and has an acid in it such as nitric or phosphoric acid. Complete control on water availability, soil sterilization is uncessary, and can be very efficient for nutrients. Wastes include rockwool (if used) and nutrient run-off. Increased possibility of root diseases.
Term
IARC
Definition
International Agricultural Research Centre. A multi-country centre for development of MVs. Big during the Green Revolution, not so much today.
Term
ICBN
Definition
International Code of Botanical Nomenclature. Controls the binomial system of nomenclature.
Term
Id maize
Definition
A cultivar of maize that doesn't produce an ear, but it has a much greater biomass. Used for biomass production.
Term
Identification
Definition
Looking at certain characteristics of a plant and applying a name based on those characteristics.
Term
Illuminance
Definition
A measure of the sensitivity of the humn eye to light. Doesn't measure what a plant is taking up, since the human eye is most sensitive to green light and plants reflect green light.
Term
Imbibitional chilling injury
Definition
Chilling injury caused by a seed taking up very cold water after germinated. It can kill the seed.
Term
Immobile element
Definition
Elements that translocate slowly. Deficiencies are more common, and resuult in physiological disorders. The element accumulates in transpiring tissues. Deficiency is first evident in younger tissues.
Term
In situ conservation program
Definition

aka On-site program

Maintenance of landraces in their natural region. Reserves where crops are grown close to their wild progenitors.

Term
Inactive red-absorbing phytochrome (Pr)
Definition
The form of phytochrome when exposed to far-red light. In darkness active far-red-absorbing phytochrome turns into it.
Term
Inches of mercury
Definition
A unit of measuring pressure used when they were still using barometers with mercury in them.
Term
Inclination of axis
Definition
The tilt of the earth's axis. This, in combination with the earth's sphere shape, changes the average intensity of radiation to change on a yearly basis: seasons.
Term
Income stability
Definition
An economic benefit to multispecies cropping. Producer provides several products and is less dependent on inputs. Less effected by price changes. Can enter new marets with reduced risks.
Term
Indeterminate
Definition
Grows continuously until environmental conditions become unfavourable. An indeterminate species never has a flower on the apical bud. Body shape and size is not fixed. Growth occurs at all stages.
Term
Indica rice
Definition

aka Hsien rice

Has a longer grain than Japonica rice and a taller, thinner, more tillered plant. Includes paddy, upland, and deep-water varieties. Predominantly tropical. Minimum temperature is 18ºC. All rice MVs are indica. Photoperiod sensitive. Found in hgih altitude and tropical rain-fed or irrigated systems. More susceptible to lodging. Has seed dormancy. Longer vegetative period. Medium yield potential.

Term
Indirect toxicity
Definition
A toxic effect where the element reduces the availability of another element or interferes with plant processes.
Term
Inflorescence initiation
Definition
Determines the number of leaves on a shoot or tiller.
Term
Infrared radiation
Definition

aka Heat radiation

Above 760 nm in frequency. We sense it as heat.

Term
Integuments
Definition
Layers surrounding the ovule. Have an opening, the micropyle. Develop into the seed coat.
Term
Intensive agricultural systems
Definition
Monoculture. High amounts of input fertilizers and pesticides. Negative impact on the soil, erosion, water quality, chemical contamination, fossil fuel use, and loss of biodiversity. Crop may be genetically homogenous and lanted uniformly. However, may be most profitable system.
Term
Intercalary meristem
Definition
The secondary meristem in monocots. Includes the basal intercalary meristem. Has two parts: lamina and ligule.
Term
Intermediate design
Definition
A combination of additive design and substitutive design in multispecies cropping.
Term
Internode
Definition
A component of a phytomer. The stem space between nodes. Number of internodes equals the number of leaves.
Term
Intine
Definition
The inner wall of a pollen grain.
Term
Iodine (I)
Definition
A beneficial element.
Term
Ion
Definition
A charged particle. Most essential mineral elements are absorbed into the plant as ions. Includes anions and cations.
Term
Iron (Fe)
Definition
A micronutrient essential mineral element. Absorbed as Fe3+ and Fe2+. Its cell function is as a component of photosynthetic electron transport chain. An immobile element.
Term
Irish potato famine
Definition
In 1845 in Irelend, potatoes were a staple crop. The potatoes had extremely low genetic diversity. A disease, potato late blight, caused a huge famine. It spread very easily due to the genetic homogeneity of the potatoes. Millions died, many emigrated to England and North America.
Term
Irradiance
Definition
The light intensity per unit of leaf surface area. Changes over time of day and time of year. To improve interception of these patterns, in Ontario it is important to have full canopy develoepd before irradiance reaches peak in June. This is why seeding early is so crucial. Increases in irradiance cause increases in transpiration and photosynthesis. Different plants have different maximum photosynthesis irradiances. Correlated to water use. In greenhouses, watering schedules are matched up with daily irradiance levels.
Term
IRRI
Definition

International Rice Research Institute

In the Philippines. Belongs to the CGIAR.

Term
Isometric row spacing
Definition
A type of row spacing where the distance between seeds in a row is the same as the distance between rows, seeds arranged isometrically. In terms of solar radiation interception, this is the bes row spacing style. You can buy planters that will plant this way.
Term
J. Harlan
Definition
A geneticist who did an experiment to see how much einkorn he could harvest using Neolithic style tools and strains. Found that he could harvest 2 kg/hr.
Term
Japonica rice
Definition

aka Sinica rice

aka Keng rice

aka Sticky rice

Has a shorter grain and a shorter, fatter, less tillered plant than Indica rice. Adapted to temperate climates. Minimum temperature is 10ºC. Includes paddy and upland varieties. Photoperiod insensitive. Found in temperate cropping sysems. Resistant to lodging. Lacks seed dormancy.

Term
Joule (J)
Definition
A unit of energy equal to the energy in one mole of photons.
Term
Jute
Definition
A fibre crop.
Term
Kenuf
Definition
A fibre crop.
Term
Kilopascal (kPa)
Definition
A unit to measure air pressure. Used by Canadians. Equal to 1000 Pa.
Term
Kingdom Plantae
Definition
Has five divisions: Lycopodiophyta, Equisetophyta, Polypodiophyta, Pinophyta, and Angiosperms.
Term
Labour productivity
Definition
An economic benefit to multispecies cropping. Labour is more distributed over the year.
Term
Lambs-quarter
Definition

aka Goosefoot

aka Chenopodium

Now considered a weed, it used to be cultivated by the Native Americans of northeasrn North America.

Term
Lamina
Definition
Part of the intercalary meristem in monocots. The leaf.
Term
Land classification system
Definition

Class 1 = the best land with no agricultural limitations

Class 2 = the worst land with no capability of growing anything.

Term
Land Equivalent Ratio (LAR)
Definition
Can include TER and MER in the calculations. Compares the difference between productivity between the intercrop and its crops in a monocrop situation. Assumes the optimum DER.
Term
Landrace
Definition
A variety of crop or breed of animal that is specifically adapted to a local region. Balanced, integrated mixture of genotypes. High level of genetic and phenotypic variation. No science-based breding was done. Often have a special use in the human culture of the local region. Buffers the spread of diseases.
Term
Lateral meristem
Definition
A secondary meristem between the xylem and phloem. Increases diameter of the stem. Includes vascular cambium and cork cambium.
Term
Lateral shoot
Definition
Branches coming off the main stem.
Term
Leaching
Definition
Nutrients being carried to the water table and completely lost. Causes water contamination.
Term
Lead (Pb)
Definition
A heavy metal
Term
Leaf Area Duration (LAD)
Definition
The length of time LAI is maintained.
Term
Leaf Area Ratio (LAI)
Definition
The ratio of leaf surface (one-sided) to ground area occupied by the crop. LAI needs to be 3 or 5 for dicots and 8 to 10 for grasses to get optimum irradiance. The amount of radiation that is captured depends on canopy architecture. As LAI goes up, so does solar radiation interception and CGR. But this effect plateaus after a certain point.
Term
Leaf Area Ratio (LAR)
Definition
THe ratio between leaf lamina and total plant mass. The relative leafiness of the plant.
Term
Leaf primordia
Definition
Forms when thhe shoot apical meristem divides, making swellings on the stem apex. Surround the apex, forming an auxillary bud.
Term
Leaves
Definition
A vegetative organ. A primary tissue produced by the apical meristem.
Term
Lentil
Definition
A pulse crop.
Term
Light compensation point
Definition
The irradiance level at which CER is zero. Different for all plants.
Term
Light competition
Definition
Competition between plants for light. Difficult to calculate in multispecies cropping systems because the architecture is complex. Best to mix a tall, erect-leaved plant with a short prostrate-leaved plant.
Term
Light quality
Definition
The wavelengths present in light. Changes with time of day, weather, latitude, and shading. Plants detect it using phytochrome and cryptochrome. Effects plant processes, growth, and development, including germination. Shade promotes stem elongation.
Term
Light saturation point
Definition
The irrradiance level where CER shows no appreciable increase. Different for all plants.
Term
Ligule
Definition
Part of the intercalary meristem in monocots. A small lip where the lamina attaches to the rest of the plant.
Term
Linear phase
Definition
The second phase in a sigmoid growth curve. A steep line as the plant reaches maturity.
Term
Linoleic fatty acid (18:2)
Definition
An essential fatty acid. Has 18 carbons and 2 double bonds.
Term
Linolenic fatty acid (18:3)
Definition
An essential fatty acid. Has 18 carbons and 3 double bonds.
Term
Lipids
Definition

aka Fat

A reduced organic biomolecule created by plants out of oxidized materials. A primary compound.

Humans need 0.12 to 0.15 day.

Term
Log phase
Definition
The first phase in a sigmoid growth curve. A shallow line as the plant begins growing.
Term
Long-day plants
Definition

aka Short-night plants

A photoperiod response classification of vegetable cropps. Plants that flower when the night is below a certain number of hours. Bloom in the summer. Usually a temperate climate plant. Many develop as leaf rosettes during short days. Productin is limited to late parts of the season. Includes radishes, rhubarb, beets, Chinese cabbage, spinach, and lettuce.

Term
Long wave heat radiation
Definition
Radiation around 10,000 nm in wavelength. The earth reflects shortwave radition in this form. It doesn't have enough energy and gets stuck in the atmosphere, causing the greenhouse effect
Term
Lumen
Definition
The light intensity equal to one standard candle.
Term
Lupins
Definition
A pulse crop.
Term
Luvisol
Definition
A classification of soil characteristic of forested regions. Has clay accumulated in the subsoil. May have a leafy humus surface horizon.
Term
Lux
Definition
Lumen per square meter.
Term
Lycopodiophyta
Definition
A division of the kingdom Plantae.
Term
Macronutrient
Definition
Essential mineral elements required at 1000 ppm or greater. Nitrogen, phosphorus, potassium, sulphur, magnesium, and calcium.
Term
Magnesium (Mg)
Definition
A macronutrient essential mineral element. Absorbed as Mg2+. Less available in acidic soils. Its cel function is as a component of chlorophyll and as an enzyme activator. A mobile element.
Term
Maintenance respiration
Definition
Respiration that maintains existig plant structures. Doubles in rates for every 10ºC increase in temperature.
Term
Manganese (Mn)
Definition
A micronutrient essential mineral element. Absorbed as Mn2+. It has a toxic effect in acidic soils. Its cell funciton is as an enzyme activator.
Term
Maximum temperature
Definition
The highest temperature at which a plant can grow.
Term
Mean relative growth rate (R)
Definition

W = weight 

t = time

R = (lnW2 - lnW1) / (t2 - t1)

Term
Measles
Definition
A common plant symbtom of toxicity effects. Black specks on leaves and fruit.
Term
Medic
Definition
A cover crop.
Term
Mediterranean climate
Definition
Wet winter, dry summer
Term
Megagametophyte
Definition
The female gametophyte. The ovule.
Term
Megasporocyte
Definition
Creates the megagametophyte, the ovule. A diploid cell that divides meiotically, creating an egg cell, two synergid cells, three antipodal cells, and one binucleate cell. All are haploid except for the binucleate cell.
Term
Membrane-bound transporter
Definition
Holes in the plasmalemma through when specific ions can travel from the apoplasm to the symplasm. This is driven by active uptake.
Term
MER
Definition
Monetary Equivalent Ratio
Term
Meristem
Definition
A growing point on a plant. Has accretional growth. Apical or intercalary meristems. Has three parts: region of cell division, region of cell elongation, and region of cell maturation.
Term
Mesoamerican bean domsetication
Definition
Beans had vicarious domestication. In Mesoamerica the pinto, pin, and black bean were domesticated.
Term
Microgametophyte
Definition
The male gametophyte. Pollen.
Term
Micronutrient
Definition

aka Trace nutrients

An essential mineral element required at 1000 ppm or less. Chlorine, iron, boron, manganese, zinc, copper, molybdenum, and nickel.

Term
Micropyle
Definition
The opening in the integuments of an ovule.
Term
Microspore
Definition
Diploid cells created by the microsporocyte. Divides mitotically to create the tube cell and generative cells.
Term
Microsporocyte
Definition
Creates the microgametophtes in the anthers. A diploid cell that divides meiotically, making three haploid microspores.
Term
Millet
Definition
A cereal crop. Includes pearl millet.
Term
Millibar (mb)
Definition
A unit for measuring air pressure. Equalt to 100 Pa.
Term
Mineral salt
Definition
A compound that ionizes in water. Example: ammonium nitrate.
Term
Miscanthus
Definition
A perennal fuel crop used to make ethanol. Makes use of marginal land. Produces a phenomenal amount of biomass. Takes two years to develop, then produces for 20 years.
Term
Mixed grain
Definition
A cereal crop. Mixed intercropping of at least two of: wheat, tye, barley, oats, or triticale.
Term
Mixed intercropping
Definition
Intercropping with indistinct organization.
Term
Melonseed
Definition
An oil seed crop.
Term
Mobile element
Definition
An element that can translocate quickly. Deficiencies show up in older tissues first, because developing tissues take the element from them.
Term
Mocca
Definition
A tuber crop that has a compound with positive health effects.
Term
Molar concentration (M)
Definition
A unit used to measure concentration. Moles per liter.
Term
Moldboard plow
Definition
The most extreme plow. The entire soil is inverted.
Term
Mole (mol)
Definition
An Avagadro's number of something, usually molecules.
Term
Molybdenum (Mo)
Definition
A micronutrient essential mineral element. Absorbed As MoO42-. Its cell function is as a component of nitrate assimilatory enzymes. An immobile element.
Term
Monocot
Definition

aka Liliopsida

aka Monocotyledonae

One of the divisions of angiosperms. Embryo has one cotyledon. Vascular bundles are arranged irregularly in the stem. Mostly herbaceous. Leaf verins are parallel, fused at the leaf tip. Flower petals are in multiples of three. Vegetative meristem is below soil level. Has intercalary and apical meristems in the primary plant body.

Term
Monocrop
Definition
One single crop species grown in a field over time without rotation. Results in yield lag.
Term
Monsoon/savannah climate
Definition
Wet summer, dry winter.
Term
Motile
Definition
Able to move. Animals are motile, and move around to find food and avoid dangers. They have senses to aid in this.
Term
Mouse ear cress
Definition

aka Arabidopsis thaliana

A common model organism. Used often in scientific experiments. Geneticists have been able to modify its genes for seed dispersal. The first plant to have its whole genome sequenced.

Term
Mt. Forest
Definition
A circular region of souther Ontario which has 2700 CHU. It has lower CHU than the surrounding areas because it is higher in elevation.
Term
Mulch
Definition
Holds water, but cools the soil, contributing frost damage.
Term
Multispecies cropping
Definition

Systems with more than one spcies. Popular for sustenance farming in tropical regions, but applicable in all AEZ.

Attributes: frequency of rotation, numer, type, and density of mixing, and heterogeneity of canopy.

Advantages: productivity, stability, resilience, sustainaility, biodiversity, pest resistance.

Disavantages: harder to manage, technologies not available.

Term
Mustard
Definition
An oil seed and flavour crop.
Term
Mutualism
Definition
Two-way facilitation.
Term
Modern Variety (MV)
Definition
A high-yielding crop variety created during the Green Revolution. 35% are from IARCs, 15% from NARCs, and 7% have an IARC ancestor.
Term
Mycorrhizae
Definition
Fungi involved in a symbiotic relationship with plants, providing them with phosphorus.
Term
N-fixing bacteria
Definition
Bacteria involved in symbiotic N2 fixation. Turn N2 into nitrogen forms availabable to the plant.
Term
N2
Definition
A gaseous form of nitrogen abundant in the atmosphere. Unvavailable to plants except through symbiotic N2 fixation.
Term
NADPH
Definition
An energy-containing compound created in photosynthesis. A primary compound.
Term
NARC
Definition

National Agricultural Research Centre

A single-country research centre for creating MVs. Big during the Green Revolution. Not so much today.

Term
Natural classification
Definition
A practical classification system. Plants are grouped based on growth habits and physical features.
Term
Natural ecosystems
Definition
Have a high level of biodiversity in comparison to agroecosystems.
Term
Neanderthal
Definition

aka Homo neanderthalensis

A close cousin to humans. Lived in Europe, Near East, and Northern Africa 250,000 - 30,000 years ago. Had a larger body and brain than humans. Lived in small bands, hunter animals, had language and music, cared for their sick and injured, and burried their dead.

Term
Necrosis
Definition
Death of leaves. A deficiency symptom.
Term
Neolithic Revolution
Definition

12,000 - 8,000 y.a.

Agriculture began. No conclusive reason as to why: could have been climate change. Agriculture began in multiple centres around the world simultaneously. Settled communities with higher population density. Civilizations developed. Fields and pastures created. Human population increased. Went from egalitarian to hierarchical societies. Slash and burn agriculture. Use of axes, hoes, and sickles. Domestication of crops and livestock from intentional breeding. Granoculture. Emmer wheat, einkorn wheat, sheep, and goats domesticated 11,000 - 8,000 years ago. Cattle, pigs, and barley domesticated 9,000 - 8,000 years ago. River basins drained.

Term
Nickel (Ni)
Definition
A micronutrient essential mineral element. Absorbed as Ni2+.
Term
Nicolai Vavilov
Definition
A Russian geneticist who, in the 1920's, found that crops originated only in tropical/subtropical regions at middle elevations (1000m - 2000m), where the land has a variable topography, and there are dry and wet seasons.
Term
Nitrate
Definition

NO3-

An ion form of N available to plants. An immobile element in the plant, but very mobile in the soil. Easily leaches.

Term
Nitrogen (N)
Definition
A macronutrient essential mineral element. The most commonly limiting element in agriculture. Absorbed through the soil through symbiotic N2 fixation. Its cellular function is protein synthesis, incluing chlorophyll, DNA, and RNA. Deficiency results in chlorosos, starting with older leaves. N may be unevenly distributed in a field, but farmers apply uniformly based on the most lacking areas. Over-application of nitrogen can result in excessive stem elongation. Managed with timing and rates of fertilizers, manures, and legumes. Fertilizers are expensive and energy-intensive to produce.
Term
No Green Revolution (NGR)
Definition
A hypotheticcal scenario where the Green Revolution never happened. Production is 22% lower in poor countries, but 2.4% higher in rich countries. Food prices are 66% higher. Caloric intake is 14.4% lower. Number of malnourished children is 7.9% higher (32 - 42 million children). No "food crisis", but there is a "welfare crisis".
Term
No IARC (NIARC)
Definition
A hypothetical scenario where there were no IARCs during the Green Revolution, only NARCs. Green Revolution is at 60% of its actual magnitude.
Term
No-till
Definition
A system with no tillage. No evidence that it increases soil organic matter, just accumultes it closer to the surface. Moisture is held in the soil strongly. Good if drainage isn't a problem.
Term
Node
Definition
A comopnent of a phytomer. Numer of nodes equals the number of leaves.
Term
Nomenclature
Definition
The giving of correct names according to the ICBN.
Term
Non-food use
Definition
A food loss. When things that can be eatend are used to create fuel or fibre.
Term
Non-motile
Definition
Cannot move. Plants are non-motile.
Term
Normal lapse rate
Definition
It gets cooler as you go up in altitude. Greenhouse effect occurs from the surface upward. Radiation is absorbed by gasses close to the earth.
Term
Nutrient recycling
Definition
A benefit of multispecies cropping. Species exist at diferent soil depths, increasing nutrient efficiency and reducing leaching.
Term
Oats
Definition
A cereal crop. Can be a cover crop. Can be plnted right after wheat is harvested. When harvested it must be crimped, or it will grow back from the base. Found in annual pastures.
Term
Oil palm
Definition

aka Elaeis guineensis Jacq.

A tropical oil seed crop, mainly grown in Malaysia and Indonesia. Yields palm oil and palm kernel oil from the fruit and seed, respectively. Yields much more oil than canola or soybean.

Term
Oil seed crop
Definition
Crops produced for vegetable oil and/or protein meal. Seeds are high in oils. Tropical oils tend to have shorter, more saturated fatty acids. Protein meal, a by-product of oil extraction, can be used as animal feed.
Term
Oilseed radish
Definition
A cover crop. A form of biotillage. Produces a long tuber with a wide diameter. Loosens the soil. It is gainin popularity.
Term
Olive
Definition

Olea europea L.

An oil seed crop. A large stout evergreen tree. Requires 200 mm rainfall minimum, optimally 400 mm - 600 mm. Chilling requirement is 1000 hours. Minimum temperature -15ºC for short periods. There are different varieties for oil and picking. Yields 18 - 50 kg/tree. Roots are 3 m deep, 4 - 7 m radius. Drought tolerant. Have heavy fruit crops one year and light the next year because heavy fruiting exhuasts the tree, and there is insufficient carbohydrates to produce fruit in the next year.

Term
Optimal range of temperatures
Definition
The range of temperatures at which a plant can grow. Different for different plants.
Term
Optimum temperature
Definition
The best temperature for growth of a plant. May change as the plant develops.
Term
Orchardgrass
Definition
A grass forage crop. Found in established pastures.
Term
Order
Definition
The taxon under subclass. Contains family.
Term
Organic carbon
Definition
Carbon sequestered from the atmosphere by photosyntehsis.
Term
Organic matter
Definition

Increases soil moisture, and improved soil aggregation, water infiltration, drainage. Reduced compaction, and erosion.

Components:

40% - 45% very stable humus

40% - 45% moderately decomposable

10% - 15% easily decomposable. The most important component. Consists of living organisms.

Term
Organic solar panels
Definition
Less common than silicon solar panels. Very new invention. Thin and diverse. Developing it so that it can be painted onto a surface, making anything into a solar panel.
Term
Oryza glaberrima
Definition
A rice species originated in Africa. Grown in remote areas of western Africa. Adapted to adverse conditions. Lower yielding than Oryza sativa.
Term
Oryza sativa
Definition
Rice originated in Asia. This species provides half of humans with calories daily. Domesticated in China. There are three kinds: deep-water, paddy, and upland.
Term
Outcrossing
Definition
When a plant crosses with another plant to reproduce.
Term
Ovary wall
Definition
The outer layer of the ovule. After fertilizatoin devlops into the fruit.
Term
Ovule
Definition
The megagametophyte. Created from the megasporocyte. Supported by the funiculus. Surrounded by two integuments. One side is the micropyle side and the other is the chalazal. After fertilization it develops into the seed.
Term
Oxidative metabolism
Definition

aka Cellular respiration

Requires gas exchange. Animals and plants have it.

Term
Oxidized material
Definition
Used by plants to make reduced organic biomolecules. Water, carbon, and minerals.
Term
Oxygen (O)
Definition
An essential non-mineral element. Absorbed as CO2, H2O, and O2.
Term
Paddy rice
Definition

aka Threshed rice

aka Unhulled rice

Commonly grown in shallowly flooded fields.

May also refer to...

aka Unmilled rice

Rice that still contains the bran and hull.

Term
Partial pressure
Definition
The proportion of pressure due to a certain gas.
Term
Parts per million (ppm)
Definition
A unit to measure concentration. Milligrams per liter.
Term
Pascal (Pa)
Definition
A unit used to measure air pressure. Newtons per meter squared. At sea level air pressure is 101325 Pa.
Term
Pasta wheat
Definition

aka Free-threshing wheat

aka Naked-grain wheat

aka Triticum durum

An emmer wheat bred to have a thinner glume. Easier to thresh. Used to make pasta.

Term
Pea
Definition
A pulse crop.
Term
Peanut
Definition

Arachis hypogeae

aka Groundnuts

An oil seed crop. Optimum temperature is 27ºC - 30ºC. Requires 200 mm - 500 mm of rinfall. Yields up to 5000 kg/ha, but realistically 800 kg/ha. Must be grown in a rotation to avoid diseases.

Term
Perennial
Definition
A lifecycle classficiation of vegetable crops. Reuire an establishment period of 2 to 3 years before harvest is possible. Plants that live for more than one year. Don't put all their energy into reproductive growth. Include asparagus, globe artichoke, and rhubardb.
Term
Perennial grasses
Definition
Intercropping of two grasses mixed together.
Term
Perihelion
Definition
The day the earth is closes to the sun. January 3.
Term
pH
Definition
The acidity of a solution. Effects mineral availability by its effect on soil chemistry and its effect on nutrient uptake by the plant. Soil pH is between 6.2 and 6.8. Soilless substrate is 5.4 to 6.0.
Term
Pharmaceuticals
Definition
One of the things plants provide for us.
Term
Phenology
Definition
The timing of crop growth and development. Must match the conditions at the plant's sire in order to flourish. Capture and use resoruces (light, water, minerals), and generate a harvestable yield.
Term
Phloem
Definition
Tubes that deliver sugars from the leaves to the roots of plants. Encased in the endodermis.
Term
Phloem-immobile elements
Definition
Elements that cannot move through the phloem, so instead them must move through the xylem.
Term
Phosphorus (P)
Definition
A macronutrient essential mineral element. The second most commonly limiting element in agriculture. Absorbed as H2PO4- nd HPO42-. Bound tightly in the soil. May absorb phosphorus through mycorrhizae. Its cell function is as a component of ATP. A mobile element. Deficiency causes a reddish-purple colour in leaves.
Term
Photoautotroph
Definition
An autotroph that turns light energy into energy-containing compounds.
Term
Photometer
Definition
A device used to measre foot-candles and lux.
Term
Photomorphogenesis
Definition
A developmental response to light quality or duration. Can cause leaf expansion, chlorophyll formation, chloroplast development petiole and stem elongation, seed germination, and flowering. Can also cause photoperiodism.
Term
Photon
Definition
A particl eof light, accoring to quantum theory. One photon has a quantum of energy.
Term
Photoperiod
Definition
The length of the light period on a particulra day of the year. Effects crop phenology such as flowering, devlopment of vegetative organs, and dormancy, including potatoes, onions, and strawberry stolons. Effects fall colouration in woody plants. There are short-day and long-day plants.
Term
Photoperiodism
Definition
A type of photomorphogensis, where the plant is sensitive to photoperiod.
Term
Photosynthate
Definition
Sugars created by photosyntehsis that are left over from maintenance respiration. Goes toward plant growth and devlopment.
Term
Photosynthesis
Definition
The creation of energy-containing compounds out of light energy. Done in the chloroplasts, only during the day. A solar hydrogen fuel cell. PAR light is absorbed by chlorophyll. Absorbs mostly red and blue light, but works best with blue light. The antenna network captures light energy, then concentrates the energy in the center, breaking apart a water molecule into O2 and high-energy protons and elenctrons, which are used to make ATP and NADPH. In theory, this can be 5% efficienty. In a field it is actually 0.5% due to stresses. Photosynthetic rate doesn't change with temperature.
Term
Photosynthetically active radiation (PAR)
Definition

aka Visual radiation

Frequency of 390nm - 760 nm. Can be seen by humans and absorbed by plants through photosynthesis.

Term
Phototropism
Definition
A form of photomorphogenesis. Plants growing towards a light source. Crytochrome is a factor. It is effected by blue light.
Term
Physical barrier effect
Definition
A form of pest/disease suppression in multispecies cropping systems. Canopy architecture and microclimate is changed, so the spread of pests is decreased.
Term
Phylogenic classification
Definition
A practical classification system. Plants are grouped based on evolutionary pedigree.
Term
Phytochrome
Definition
A photoreceptor that detects the red/far-red light ratio. It changes back and forth between its two forms, Pr and Pfr. In darkness Pr builds up.
Term
Phytomers
Definition
Units that make up shoots. Stem node, internode, leaf, and auxillary bud.
Term
Pigeon pea
Definition
A pulse crop.
Term
Pima cotton
Definition

aka Sea Island cotton

aka Gossypium barbadense

A cross between Gossypium arboreum and Gossypium herbaceum. The combination of these species creates much higher fibre yields.

Term
Pinophyta
Definition
A division of the kingdom Plantae. Contains gymnosperms.
Term
Planck's constant
Definition
6.62e-34 J/s*photon
Term
Planned biodiversity
Definition
The variety of species intentionally included in an agroecosystem. Crops, livestock.
Term
Plant life cycle
Definition
Seed dormancy. Seed germination. Growth and development. Maturity. May become dormant at this point if prennial or biennial. Flowering. Pollination/fertilization. Seed development. Seed dispersal.
Term
Plasmalemma
Definition
The plasma membrane around a plant cell. Selectively permeable. Water must pass through it to get to the symplasm.
Term
Plastid
Definition
A class of organelles present only in plants. Includes chloroplasts.
Term
Plow
Definition
Invented circa 1000 AD. Tills the soil. Better than an ard. Moldboard plow, chisel plow, disc-ripper, sub-soiler, disc, cultivator, harrow, roto-tiller, rotary hoe, packer, and hand implements.
Term
Pollen grain
Definition
The microgametophyte. Created by the microsporocyte in the anthers. Consists of an exine, intine, some starch or oil (depending on species), a tube cell, and a generative cell.
Term
Pollination
Definition

When pollen lands on a stigma. Can be self-pollination or cross-pollination. The pollen may have been transported by animal or by wind. The tube cell forms a pollen tube down the style, making a path for the sperm cells.

A way of classifying vegetabe crops. Include self and cross pollinating crops.

Term
Polyploid
Definition
Having more than two copies of each gene and chromosome. There are autopolyploids and allopolyploids.
Term
Polypodiophyta
Definition
A division of the kingdom Plantae. Ferns.
Term
Popcorn
Definition

aka Zea mays praecox

A variety of corn. Flint corn with a very high content of hard starch, with a soft starch core. Kernel is small.

Term
Poppy
Definition
An oil seed crop.
Term
Potassium (K)
Definition
A macronutrient essential mineral element. The third most commonly limiting element in agriculture. Absorbed as K+. Cell function is as a charge balancer, in stomatal function, and enzyme activation. A mobile element. Deficiency causes chlorosis and necrosis at leaf tips and edges and weakening of stems.
Term
Potato
Definition
A Solanaceae crop. A sector of Canadian horticulture. Prouces $1.1 billion/year in Canada, mostly in the Maritimes and Manitoba. A tuber crop. Tubers are vegetatively propagated. An annual. Shallow-rooted. High in calories, but not considered an agronomical product because it is not stored dry like a grain. It can be stored for long periods with minimal decrease in quality. It is propogated asexually, so it has little genetic diversity. Likes to grow in sandy soils.
Term
PPFD
Definition

Photosynthetic Photon Flux Density

μmol/m2*s 

Measured with a quantum meter.

Term
Practical classification system
Definition
A system for classifying plants. Agricultural use, natural classification, phylogenic classification, and scientific classification.
Term
Pre-agrarian
Definition

42,000 - 12,000 years ago

Hunting and gathering. Husbandry of wild plants and animals (but not intentional breeding). Use of stone tools. Land clearing using fire. Sowing of seeds. Harvesting, threshing, winnowing, and grinding to produce flour. Possibly alcohol production. Legumes, roots, tubers, and animals harvested.

Term
Precipitation
Definition
An aspect of weather and climate. Effects crop/cultivar suitability, production intensity, residue management, tillage, nutrient management, pests, and cover crops. In Ontario in the winter, it is greater than evapotranspiration, so it results in a build-up of soil moisture in the spring.
Term
Pressure
Definition
The force exerted against a surface by continuous collisions with gas molecules. Effected by temperature and air density. An aspect of weather and climate.
Term
Primary compounds
Definition

aka First degree compounds

Compounds necessary for plants to complete their life cycle. DNA, RNA, protein, carbohydrates, lipids, vitamins, hormones, ATP, and NADPH.

Term
Primary endosperm nucleus
Definition
A triploid cell formed when a sperm cell combines with the binucleate cell. Develops into the endosperm.
Term
Primary growth
Definition
Growth from the apical meristems. Increases plant length. Produces primary tissues.
Term
Primary tissues
Definition
Produced by primary growth. Some monocots are entirely primary tissue. Branhces, leaves, flowers, and adventitious roots.
Term
Protein
Definition
A reduced organic biomolecule created by plants out of oxidized materials. A primary compond. Humans need 0.25 - 0.33 a day. Nitrogen and sulphur are required in making it.
Term
Pulse crop
Definition
Legume crops high in protein and starch. Tend to have complementary proteins to cereal crops. Low in methionine, but high in lysine.
Term
Quantitative short-day plant
Definition
A plant that is short day, but requires a specific photoperiod to flower at the correct time. Example: soybeans.
Term
Quantum
Definition
The amount of energy a photon has. This energy is proportional to the frequency of light.
Term
Quantum efficiency of photosynthesis
Definition
The net CO2 fixed per unit of leaf area divided by the photons absorbed per unit of leaf. The derivative of light response curve Theoretical maximum is 1:8. In C3 plants it is 1:20 - 1:25. In C4 plats it is 1:16 - 1:20. Using breeding to improve it has limited results.
Term
Quantum meter
Definition
A device used to measure PPFD.
Term
Quantum theory
Definition
The theory that light travels through space as a strem of photons.
Term
Quinoa
Definition
A cereal crop. The only cereal crop that is not a grass.
Term
Radiation
Definition
A heat transfer mechanism. The only way heat can travel through space.
Term
Rapeseed
Definition
An oil seed crop. Canola was developed from this plant.
Term
Ratoon cropping
Definition
Intercropping where the plant produces a sucker plant (asexual reproduction), and the mother plant is harvested. Example: banana.
Term
Red clover
Definition

Trifolium pretense.

A legume forage crop. Can be a cover crop. Reduces insect pests. Fixes nitrogen. Underseeded beneath winter wheat in corn/soybean/winter wheat rotations. Adds nitrogen to the soil. Shade tolerant. Establishes early. Found in established pastures. Seeded in the fall and regrows in the spring, or is seeded in the spring. Benefits yield, soil, and nitrogen. Some issues with stand uniformity.

Term
Red/Far-red light ratio
Definition
The ratio between red and far red light. Detected by phytochrome.
Term
Red rice
Definition
A hybrid between rice and wild rice. Looks extremely similar to rice, but is actually a weed. Has a slightly darker grain. When milled, the grain shatters.
Term
Reduced organic biomolecules
Definition
Created by plants out of oxidized materials. DNA, RNA, protein, carbohydrates, lipids, vitamins, and hormones.
Term
Red light (R)
Definition
Light with a frequency of 660 nm.
Term
Reed canarygrass
Definition
A grass forage crop. Found in established pastures.
Term
Region of cell divison
Definition
The true meristem. The region of the meristem where cell division occurs. The only place in a plant where cell division occurs. Calcium is required by this region.
Term
Region of cell elongation
Definition
The region of the meristem after the region of cell division, where cells enlarge and elongate. They generally elongate parallel to the direction of growth. Calcium is required in this region.
Term
Region of cell maturation
Definition
The region of the meristem after the region of cell elongation, where the cells mature and differentiate into their final forms.
Term
Relative humidity (RH)
Definition
The vapour pressure divided by the saturated vapour pressure at specific air temperature. Expressed as a percent. An aspect of weather and climate.
Term
Relay intercropping
Definition
Species mixing over time. Two crops are in the field together only if/when the lifecycles of both collide. One or two strata levels. Partially overcomes the mechanization barrier of multispecies cropping.
Term
Reproductive floral organs
Definition
A vegetative organ. Never permanent. Formed when the vegetative meristem turns into a floral meristem.
Term
Reproductive growth
Definition
Annuals put all their energy into it. Perennials do not.
Term
Residue
Definition

aka Trash (don't call it this)

Crop remains left in the soil. May be left on the surface or incorporated by tillage. Increases soil moisture retention. Effects disease and insect pressure. Inhibts weeds. Can inhibit planting.

Term
Resource biota
Definition
Species that contribute to the crop. Pollinators. Decomposers.
Term
Respiration
Definition
Uses sugars to release energy and CO2. Occurs in the mitochondria. Occurs 24/7, even through the night.
Term
Revolution
Definition
The earth orbits the sun in an ellipses once every 365.25 days.
Term
Rice
Definition

Asian: Oryza sativa

African: Oryza glaberrima

A major cereal grain. Grown in tropical and sub-tropical latitudes. There are thousands of cultivars, classified into Indica, Japonica, and Javanica. Self-fertilizing. A C3 crop. Staple in southern and southeastern Asia. China produces most of the world's rice. Many varieties. Can be grown on dry land or in paddies. Photoperiod insentive cultivars can produce 2 to 3 crops a year. Can grow in flooded fields or dry upland systems. Transplanted or direct seeded. Susceptible to rice blast, bacterial blight, and tungro virus. Insect pests include stem borers, leaf-folders, armyworms, cutworms, plant hoppers, and leaf hoppers. Also rats and birds. Optimal temperature is 30º - 32ºC. Harested and threshed by hand or machine. Storage method is crucial; must be free from spoilage, insects, and rats. Grain size, shape, colour, and cooking properties are important for a variety's economic success. Takes 90 - 120 to grow. With faster growing varieties, multiple crops can be produced a season.

Term
RNA
Definition
A reduced organic biomolecule created by plants out of oxidized materials. A primary compound. Nitrogen is required in making it.
Term
Rockwool
Definition
A modified insultion material used as a hydroponic substrate. Comomnly used in greenhouses. Non-biodegradable. It is a waste after used.
Term
Root
Definition
A vegetative organ.
Term
Root and tuber crops
Definition
The root is the edible portion. Usually starchy. Historically important staple foods.
Term
Root cap
Definition
A structure at the very tip of the root prior to the root meristem.
Term
Root competition
Definition
Competition between plants for water and nutrients. Minimized in a multispecies cropping system by using plants that mine different depths of the soil, andor require nutrients at different times, amounts, and/or chemical forms. Example: legume/cereal, or C3/C4.
Term
Root hair
Definition
A hair-like extension on a root cell that increases root surface area for water and nutrient uptake.
Term
Root meristem
Definition
Apical meristem in the root.
Term
Root pericycle
Definition
A meristem that forms secondary (branching) roots.
Term
Root structure
Definition
Impacted by soil structure. Roots like well-aggregated soil.
Term
Root-zone substrate
Definition
Medium instead of soil for growing hydroponically. Includes rockwool, coire (coconut fibre), or wood shavings. Plants grow faster in substrate than in liquid based hydroponics.
Term
Rosette
Definition
Formed in the first year of a bienneial plant. A rose-like bunch of leaves.
Term
Rotation (of crops)
Definition
Repeated cultivation of succession of crops, sole, or mixed, often with fallow.
Term
Rotation (of the earth)
Definition
The earth is spinning in a circle. This effects the amount of sunlight and heat throughout a day.
Term
Row intercropping
Definition
Strip intercropping. Alternating species in rows. Two species, one or two strata levels. Partially overcomes the mechanization barrier of multispecies cropping.
Term
Row spacing
Definition
The pattern in which crops are planted in a field. Effects the solar irradiation interception and solar energy efficiency. Traditiona, equidistant, and isometric.
Term
Rye
Definition
A cereal crop. Can be a cover crop.
Term
Safflower
Definition
An oil sed crop.
Term
Salinity
Definition
The concentration of salts in a solution.
Term
SALTUS (pasture) / AGER (cropland)
Definition
A method for renewing soil fertility used in early agricultural systems. Animals pastured during the day and penned in cropland at night. The cropland benfits from manure without being grazed.
Term
Saturated fatty acids
Definition
Fatty acids with no kinks in the chains. Can lead to heart disease. More solid at room temperature.
Term
Saturated vapour pressure
Definition
The maximum possible vapour pressure for a gas at a given temperature.
Term
Scientific classification
Definition
A practical classification system. Plants are grouped based on similarities in anatomy. Uses the binomial system of nomenclature.
Term
Second modern agricultural revoltion
Definition
1840's. Mineral fertilizers used. Superphosphate factories. The Haber-Bosch process. Steam engine tractors invented in the 1850's. Internal combustion tractors invented in the 1940's.
Term
Secondary compounds
Definition

aka Second degree compounds

Compounds produced by plants, but aren't necessary for them to complete their life cycle. There are thousands. Defensive compounds to deter herbivores, pathogens, or other plants. Some secondary compounds are used in human pharmaceuticals.

Term
Secondary growth
Definition
Growth in the secondary meristems. Increases diamter of primary tissues.
Term
Secondary meristem
Definition
In dicots it is the vascular cambium. In monocots it is the intercalary meristem.
Term
Seed
Definition
A plant embryo with a food source (endosperm or cotyledons), and a seed coat.
Term
Seed coat
Definition
The outer layer of the seed. Formed from the integuments.
Term
Seed dormancy
Definition
Wild plant seeds do not always germinate when there are good conditions. They may stay in the soil seed bank for over a year. Domestication syndrome makes them germinate as soon as there are good conditions.
Term
Seed germination
Definition
The breaking of seed dormancy. Plants begin to grow.
Term
Seed shattering
Definition
Wild plants propagating their own seeds. The seeds fall off when they reach maturity, and spread themselves by various mechanisms. In grasses the rachis snaps. In legumes the pod has explosive dehiscence. Domestication syndrom makes the seed stay on the plant after maturity.
Term
Selenium (Se)
Definition
A beneficial element. Stimulates growth. Taken up in well-aerated soils as selenite. Can be poisonous to grazing animals, causing alkali disease.
Term
Self-pollination
Definition
When pollen from a plant lands on its own stigma. A pollination classification of vegetable crops. Insects or wind is not a requirement for pollination and seed formation. Includes beans, peas, and tomatoes. In greenhouses bumble bees may be used to mechanically stimulate the plant, but not for pollination.
Term
Semi-dwarf
Definition
MVs of rice and wheat that are shorter and thicker-strawed. Higher HI. Put more energy into the grain. Respond better to fertilzers. Successfull in areas with irrigation/regular rainfall.
Term
Senescence
Definition
A stage in development where phytomers are lost. Photosynthetic competence is lost. Triggered by environmental conditions.
Term
Senescence phase
Definition
The third and final stage in a sigmoid growth curve. Shallow line as the plant reaches senscence and stops growing.
Term
Sequential agroforesty
Definition
Intercropping temporarily with trees.
Term
Sequential cropping
Definition
Two or more crops planted after each other in the same field over the same growing season.
Term
Sesame
Definition
An oil seed crop.
Term
Sexual reproduction
Definition

Reproduction involving two parent plats. Pollination must occur.

A classification of fruit crops. Cultivar was bred through a controlled cross. Example: Cortland apple, and Vega sweet cherry.

Term
Scythe
Definition
Invented circa 1000 AD. Allowed for more grain to be harvested, reducing the number of animals to be slaughtered in the autumn.
Term
Shade leaf/Sun leaf
Definition
Some plants have the ability to adapt to different irradiance levels. The top leaves are thicker and the lower leaves are thinner. The leaves are different thickness depending on where they are planted. Some plants do not have this ability, such as ginseng.
Term
Shadouf
Definition
A tool used for irrigation in hydraulic systems in ancient Egypt.
Term
Shattercane
Definition
A hybrid between domestic sorghum and whild sorghum. Looks like sorghum, grows like sorghum, but has seed dispersal, so is actually a weed.
Term
Shea nut
Definition
An oil seed crop.
Term
Sheath
Definition

aka Pseudostem

In monocots the leaves grow while inside it.

Term
Shoot meristem
Definition
Apical meristem in the shoots. Forms lateral shoots.
Term
Short-day plants
Definition

aka Long-night plants

A photoperiod classification of vegetable crops. Plants that flower when the night exceeds a certain number of hours. Bloom in the winter. Usually a tropical plant. May grow indefinitely during long days. Includes sweet potatoes.

Term
Shortwave radiation
Definition
Light emitted from the sun. Frequency ranges from 300 nm to 3000 nm. The sun irradiates 90,000 TW of energy every year. We use only 20 TW of it yearly, but a third is lost through food losses.
Term
Sidedresing
Definition
Fertilizer applied between the rows of corn when it is a foot tall. This is the time when the plant needs it most. If you applied earlier, the N may have been lost.
Term
Sigmoid growth curve
Definition
The cumulative growth of an annual, determinate crop, graphed over time. Makes an S shaped curve. Has a log phase, linear phase, and a senescense phase.
Term
Silage
Definition
The whole plant. The grain as well as the stover. Used as ruminant feed; ruminants can derive protein from silage.
Term
Silicon (Si)
Definition
A beneficial element. Essential for rice.
Term
Silicon solar panels
Definition
The more common type of solar panel. Big, awkward, and heavy.
Term
Sink tissues
Definition
Tissues that obtain water and mineral elements, but do not photosynthesize. Roots.
Term
Slash-and-burn
Definition
An agricultural system widespread during the Neolithic Revolution. Axe down and burn an area of forest, then cultivte it until soil fertility declines, then move elsewhere and repeat. Some of this type of agriculture is still practiced today. In terms of energy ratio, this is the most efficient type of agriculture.
Term
Sodium (Na)
Definition
A beneficial element.
Term
Soil
Definition

A living ecosystem. Can be managed to alter water availability, erosion, planting process, root growth, fertility, pests, leveling, and compaction. Has classification, texture, and structure. A factor in choosing sites for vegetable production. Vegetables grown in a mineral or organic soil.

Composition:

45% minerals (sand, silt, clay)

25% water 

25% air

5% organic matter

Term
Soil aggregate
Definition
Clumps of soil. Influenced by tillage, rotation, earthworms, organic matter, moisture, and freezing and thawing. Effects drainage, infiltration, aeration, root growth, and yield.
Term
Soil conservation
Definition
A benefit of multispecies cropping. Increased soil cover and root presence in topsoil. Reduced erosion.
Term
Soil management
Definition
Tllage, cover crops, organic matter amendments, irrigation, drainage, crops, residue, pH amendment, and fertilizers.
Term
Soil seed bank
Definition
A build-up of dormant seeds found in the soil.
Term
Soil stability
Definition
The ability of a soil to maintain its structure when subjected to tillage, traffic, and weather. Highly stable soils can withstand poor management, and have reduced erosion.
Term
Soil structure
Definition
The size and shape of soil aggregates. A network of pores and spaces within and around aggregates.
Term
Soil temperature
Definition
Effected by timing of planting, residue, tillage, drainage, and compaction.
Term
Soil texture
Definition
The proportion of sand, silt, and clay in a soil. Determines water holding capacity, water availability, CEC, and water dynamics.
Term
Solar energy efficiency
Definition
The amount of solar energy that is actually used in an agroecosystem. Photosynthesis is 0.47% efficient, even though in theory it should be 5%. In a field system in Canada it is 0.2%. A greenhouse is 3%. This is because in a field we miss out on irradiance that comes in the winter. Only a small portion of biomass is harvested. 1. Photosynthesis, 2. Growing season, 3, HI.
Term
Solar hydrogen fuel cell
Definition
In a way, this is what chloroplasts are.
Term
Sole cropping
Definition
One crop in a field spatially. There may be rotations over time.
Term
Sorghum
Definition

Sorghum bicolor

A cereal crop. There are many cultivars. Farily widespread cultivtion. Local African landraces do very well in poor conditions, but are not the best when in good conditions. Optimal temperature is 27ºC - 28ºC. Optimal rainfall is 500 mm -  600 mm. Yields up to 3000 kg/ha, but realistically 600 kgha. Can survive in saline conditions. A coarse grain that is difficult to process. 12% protein, 3% fata, and 70% carbohydrates .Tannis in seed coat makes it harder to absorb proteins during digestion. Often it is intercropped. Flowers after rainfall to avoid diseases and pests. Plant has low harvest index. Stalks can be used as a building material for rooves and fences, and as a fuel. Not often grown in rows, more commonly broadcast seed.

Term
Source tissue
Definition
An actively transpiring and photosynthesizing tissue, such as leaves.
Term
Soybean
Definition

aka Glycine max L.

An oilseed crop. A legume. Domesticated in China. A quantitative short-day plant. C3. Legume. Used in livestock feed, food products, and biodiesel. Its may cultivars are adapted to narrow latitudinal belts. Outside of its proper region, a variety will have terrible yield.  Early maturing cultivars are grown further north, and late maturing cultivars grown further south. Susceptible to frost at temperatures below 2ºC, but can tolerate frosts because the growing ponit is above the ground. Compliments corn in feed rations and in field rotations. Rapid and uniform emergence, non-limiting fertility, and high water availability are important. Disease, insect, and weed control needed. Canada produces 1% of the world's soybeans, 60% of this in Ontario. Soybeans are 18% - 20% oil. Soybean meal is 44% protein. Soybean production in Ontario increased dramatically in the 1970s. Tillage was introduced to deal with corn residue, affecting soil quality and OM. Soybeans have a good effect on soil, but are associated with poor soil quality. Herbicide resistant weeds are an issue. High input systems.

Term
Soybean maturity group
Definition
Different cultivars of soybeans that can live in different latitudinal ranges. Group X lives in the tropics and group OO lives in norther Ontario.
Term
Spate and basin
Definition
A basin filled by an annual flood. Used in hydraulic systems in ancient Egypt. A form of macro-catchment water harvesting.
Term
Species
Definition
A group of individuals that can successfully outcross with each other
Term
Specific epithet
Definition
The second name in the binomial system of nomenclature. Tells you the species.
Term
Speed of light (c)
Definition

The speed at which light travels through space. 

300,000,000 m/s

Term
Sperm
Definition
Created from the generative. There are two in a pollen grain. At pollination they travel down the tube cell. In double fertilization one combines with the egg to produce the zygote. The other combines with the binucleate cell to produce the primary endosperm nucleus.
Term
Sphere
Definition
The shape of the earth. This causes the sun's rays to hit the earth at different angles. The higher the angle, the more intense the radiation is.
Term
SPIA
Definition
Special Project on Impact Assessment.
Reviewed CGIAR Green Revolution pojects.
Term
Sporophyte
Definition
The sporophytic generation. Free-living and self-sufficient. Seed, seedling, and mature plant.
Term
Stay-green corn
Definition
Corn that doesn't enter senescence before it is harvested. Increased LAD. This is how we get good corn yield in Ontario where our season is short.
Term
Steam plow
Definition
Invented in the late 1850's. Hedges were ripped out, fields enlarged. Fewer farm workers were needed. Increased food production. Allowed for work in mines and factories.
Term
Stem
Definition
A vegetative organ.
Term
Stem meristem
Definition
Found at the tip of every shoot, lateral or primary Includes dormant buds.
Term
Stigma
Definition
A reproductive structure. Collects pollen and connects to the micropyle.
Term
Stomata
Definition
Pores in the leaf through which CO2 enters the leaf. Also the route through which water transpires into the atmosphere.
Term
Stover
Definition
The part of the plant not harvested. The stalk, leaves, et cetera. Can be used as feed for ruminants.
Term
Stratification
Definition
A cold period required by a seed before it can germinate. It is so the seed always germinates in the spring.
Term
Strawberry
Definition

Fragaria ananassa

A cross between Fragaria chileonsis and Fragaria virginiana. This fact was discovered by Antoine Duchesne in the 18th century. Octoploid. There are June-bearing, ever-bearing, and day-neutral strawberries. Require long days and warm temperatures to grow leaves and runners. Northern cultivars need more chilling than southern cultivars.

Term
Strip tillage
Definition
Tillage in strips between rows. Has the benefit of tillage and no-till.
Term
Sub-Saharan Africa
Definition
Underwent only partial Green Revoution. Because they grow mainly root crops and tropical maie. Little increase in fertilizer use.
Term
Subclass
Definition
The taxon below class. Contains order. Has names ending with -eae or -idea.
Term
Substitutive design
Definition
Multispecies intercroping design where there is a proportional decrease in density of all crops.
Term
Sulphur (S)
Definition
A macronutrient essential mineral element. Absorbed as SO42-. Its cell function is as a component of cystein, methionine, and other biomolecules. A mobile element. Deficiency can occur in sandy soils, resulting in chlorosis, and cupping of leaves.
Term
Summer solstice
Definition
The day with the maximum photoperiod in the northern hemisphere. Sun's rays hit the Tropic of Cancer at a 90º angle. June 22.
Term
Sunflower
Definition
An oil seed crop. A Asteraceae crop. Originated in North America.
Term
Sweet corn
Definition

aka Zea mays saccharata

A variety of corn with higher sugar content when immature. Reduced starch content. Dried seeds are wrinkled. The most common Poaceae crop in Ontario. An annual. Direct seeded. Wind pollinated, but super sweet varieties must be isolated. Day-neutral. Deep-rooted. Marketed fresh or processed. Has variation in colour caused by carotenoid levels, nutrition, and sweetness. Has Bt varieties. Pests include insects, birds, racoons, and deer. Racoons are especially bad. Many herbicides are available for it.

Term
Sweet potato
Definition

Ipomoea batatas

A root crop. A short-day plant. Requires 750 mm - 1250 mm of rainfall.

Term
Switchgrass
Definition
A fuel crop used to make ethanol. Makes use of marginal land.
Term
Symbiotic N2 fixation
Definition
A method of nitrogen uptake where N-fixing bacteria convert N2 from the atmosphere into a form the plant can take up.
Term
Symplasm
Definition
The inside of the cell itself. It is surrounded by the plasmalemma. Water can enter the root this way. This is the only way water and nutrients can get into the xylem.
Term
Synergid cells
Definition
Two haploid cells created by the megasporocyte in the ovule. Stay near the micropyle end.
Term
Tall fescue
Definition
A grass forage crop. Found in established pastures.
Term
Taro
Definition
A corm crop. Classified as a root and tuber crop.
Term
Tassel
Definition
The male reproductive part of a con plant. The apical meristem moves upwards from being underground, and converts to a reproductive meristem. As it moves, the internodes become longer. It then emerges out the top of the stalk as the tassel.
Term
Taxon
Definition
Classification groups in the scientific classification. Nested in the taxonomic hierarchy.
Term
Taxonomic hierarchy
Definition

Scientific classification groups. Nested taxa.

Kingdom, division, class, subclass, order, family, genus, species.

Term
Taxonomy
Definition
The scientific of identification, nomenclature, and classification of plants. Looks at their similarities.
Term
Temperate crops
Definition
Cannot absorb radiation in the winter, loses a lot efficiency this way. Planting earlier can help.
Term
Temperate region
Definition
The area above the Tropic of Cancer and below the Tropic of Capricorn. Constant precipitation all through the year. Cooler. Has a winter, so growing season is bracketed.
Term
Temperature
Definition
An aspect of climate and weather. Effects crop/cultivar suitability, weed/pest complexes, tillage, and production practices. A factor for selecting site for fruit cropping systems. CHU, growing season temperature, dormant season temperature, minimum chilling requirements, and hardiness zones.
Term
Temperature differential
Definition
The difference between day and night temperatures. Decreasing in Ontario. Affects the devlopment of some crops. Warm days with cool nights result in higher days than with warm nights.
Term
Teosinte
Definition
The wild ancestor of maize. Lives in Mesoamerica as a weed. Short-day plant. Has a much smaller "cob", is very tillered, and smaller in size. Short-day, whereas corn is day-neutral.
Term
TER
Definition
Time Equivalent Ratio
Term
TeraWatt (TW)
Definition
A trillion Watts.
Term
Tetraploid
Definition
A form of polyloidy. Has four copies of every gene and chromosome.
Term
Thermal heat units
Definition
The number of units of heat are accumulated over the frost-heat window. Cultivars must be matched. CHU.
Term
Three sisters
Definition
Beans, corn, and squash. Planted by the Native Americans. The beans fix nitrogen, and complement amino acids in the diet. The corn is a scaffold for the beans to grown on, and carbohydrate source in the diet. The squash is a ground cover, deters pests, and complements amino acids in the diet.
Term
Tillage
Definition
Disturbance of the soil done with a plow. Reduces soil moisture. Controls vegetation. Incorporates residues, fertilizers, and/or manures. Warms/cools the soil. Reduce disease and pests. Facilitates planting. Speeds soil drying. Levels the soil. May be done solely because of tradition. Effects bulk density, aggregate size, soil structure, temperature, aeration, water status, erosion, organic matter breakdown, and biology of soil.
Term
Time range
Definition
An economic benefit to multispecies cropping. Used in perennial tree operations, where in the first few years there would otherwise be no monetary gain as plants develop.
Term
Timothy
Definition
A grass forage crop. Found in established pastures.
Term
Tissue systems
Definition
Dermal, vascular, and ground.
Term
Total biological mass
Definition
The weight of the whole plant.
Term
Totipotency
Definition
The ability to regenerate a whole plant from one sample of plant tissue. A form of vegetative reproduction.
Term
Toxic compounds
Definition
Many wild plants have unpleasant tasting and/or toxic compounds to protect them from predation. Domestication system lowers the amount or completely erases these compounds.
Term
Toxicity effect
Definition
When the concentration of an element is too high and causes bad effects on the plant. Can be direct or indirect.
Term
Traditional row spacing
Definition
Plants are close together in the row, but far apart between rows. In terms of solar radiation interception, this is the worst type of row spacing.
Term
Translocation
Definition
The movement of nutrients from one part of a plant to another. Elements have differing mobility.
Term
Transpiration
Definition
The movement of water up the xylem and out of leaves into the atmosphere through stomata. Main cause of water loss. Driven by vapour pressure deficity. Increases with irradiation, temperature, air movement, LAi, and water availability.
Term
Trap crop
Definition
A plant that diverts insects and/or pathogens to reduce damage to the main crop.
Term
Tree intercropping
Definition
More than one tree species intercropped.
Term
Triangle of U
Definition
Named after Japanese agronomist N. U. A triangle showing the crops resulting from crosses between Brassica capestris, Brassica nigra and Brassica oleracea.
Term
Trifoliate
Definition
Three bladed leaves.
Term
Triple sequential cropping
Definition
Sequential cropping with three species.
Term
Triticle
Definition
A cross between pasta wheat (Triticum durum) and rye (Secale cereal) created in the 19th century. Has the high yields of wheat and the hardiness of rye.
Term
Triticum tauschii
Definition
A diploid wild wheat species with a DD genome.
Term
Tropic of Cancer
Definition
A line around the earth where the sun's rays shine on a 90º angle on June 22, the summer solstice.
Term
Tropic of Capricorn
Definition
A line around the earth where the sun's rays shine on a 90º angle on December 22, the winter solstice.
Term
Tropical region
Definition
The area between the Tropic of Cancer and the Tropic of Capricorn. Has a dry season and a rainy season. Warmer than the temperate regions.
Term
Tube cell
Definition
A haploid cell in a pollen grain. Created by the microspore. At pollination, it forms a pollen tube down the style.
Term
Tung nut
Definition
An oil seed crop.
Term
Turgor
Definition
The pressure of the large vacuole inside a plant cell. It helps the cell keep its shape.
Term
Twentieth century breeding
Definition
The third genetic bottleneck in domestic crops. In the 1900's, scientists focused on breeding "elite varieties" with greater yields and resistance to pests/pathogens. Ended up decreasing genetic diversity.
Term
Ultraviolet radiation (UV)
Definition
Radiation below 380 nm in frequency.
Term
Undertaking on Plant Genetic Resources for Agriculture
Definition
An initiative created in 1997 to deal with the intellectual property protection of plant genetic resources.
Term
Unifoliate
Definition
One bladed leaves.
Term
Upland cotton
Definition

aka Gossypium hirstum

A cross between Gossypium arboreum and Gossypium herbaceum. The combination of these species creates much higher fibre yields.

Term
Upland rice
Definition
Rice varieties that can be grown in rainy climates without irrigation.
Term
Vanadium (V)
Definition
A beneficial element
Term
Vapour pressure
Definition
The partial pressure of water vapour. Measured by relative humidity.
Term
Vapour pressure deficit (VPD)
Definition
The difference between relative humidity inside a leaf and outside it. Inside the leaf it is usually 100%, outside it is less. This causes water to transpire out of the leaf.
Term
Vascular
Definition
A tissue system. Includes the xylem and phloem.
Term
Vascular cambium
Definition
The secondary meristem in dicots. A lateral meristem. Increases the diameter of the stem. Forms wood in woody plants.
Term
Vegetative meristem
Definition
Meristem that forms vegetative organs.
Term
Vegetative organs
Definition
Roots, stems, leaves, and reproductive floral organs.
Term
Vegetative reproduction
Definition

aka Asexual reproduction

A propagation classification of vegetable crops. Plant tissue is planted, not seed. Includes rhubarb, asparagus, garlic, horseradish, onion, and potato. Faster establishment and maturity. Maintains true-breeding or hybrid seeds; genotype is maintained. High cost. Disease spread is a big risk.

Term
Vernalization
Definition
A cold period necessary to get a plant to flower. Most winter annual plants and biennials have it.
Term
Vetches
Definition
A pulse crop.
Term
Vicarious domestication
Definition
When a plant is domesticated in more than one center. Example: common bean, cotton, and rice.
Term
Vitamins
Definition
A reduced organic biomolecule created by plants out of oxidized materials. A primary compound.
Term
Waste
Definition
A food loss. Harvest losses, storage losses, and home food waste. 33% of food energy is lost.
Term
Water
Definition

H2O

Used in photosynthesis. A lot of water is lost from the plant out through the stomates, the same pathway CO2 comes in. An important factor in horticultural systems. Vegetables need 100 mm of water a month. Average rainfall in Ontario is 70 mm a month.

Term
Water quality
Definition
A benefit of multispecies croping. Decreaes run-off and erosion.
Term
Water use efficiency (WUE)
Definition
A measure of the relatie efficiency of water use. Dry matter weight divided by the amount of water used to grow the crop. Sorghum is the best, and flax is the worst. It can be increased through plant breeding and increased fertilizer application.
Term
Water vapour
Definition
Water in gas form. A greenhouse gas. The water holding capacity of the air increases as temperature goes up.
Term
Weather
Definition
Temporary and local changes in temperature, precipitation, relative humidity, cloudiness, pressure, and wind. It is driven by solar energy.
Term
Weeds
Definition
Evolved alongside crops. May share genes with crops, making them extra bad weeds.
Term
Wet mill
Definition
A mill where ethanol is made. More versatile than a dry mill. Can also make corn starch, gluten feed, gluten meal, and oil out of corn.
Term
Wheat
Definition
Any of the grain crops from the genus Triticum. Includes bread wheat and durum wheat. Many of the species have polyploidy. A major cereal crop. Day-neutral. Grown in cooler, northern latitudes. Optimum temperature is 18ºC. Requires 250 mm - 900 mm of rainfall.
Term
White clover
Definition
A legume forage crop. Found in established pastures.
Term
White light
Definition
Visible light. Frequency range of 400nm - 700nm. The different colours appear white when mixed.
Term
Wien's Law
Definition
The hotter an object is, the shorter the wavelength of radiation will be. This is why the sun's radiation is somuch smaller in wavelength than the earth's radiation.
Term
Wild rice
Definition
Oryza nivara and Oryza rufipogon. Live in suptropical Asia. Can grow in flooded areas. Oryza nivara is the progenitor of domestic rice.
Term
Wild wheat
Definition
Grasses belonging to Triticum and Aegilops. Live near the Fertile Crescent. There are two kinds: einkorn and emmer.
Term
Wind
Definition
An aspect of weather and climate. Has speed and direction. Wind makes a plant grow shorter. This problem is eliminated in a greenhouse.
Term
Wind erosion
Definition
When soil is blown around. Silt and clay particles.
Term
Wind machine
Definition
A huge fan used to reduce frost damage. It blows the higher, warmer air onto a crop during the night. Used mainly for fruit crops.
Term
Winter annual
Definition
A crop where the seeds are planted in the fall. Some germinate in the fal land survive the winter as seedlings. Others germinate in the spring. Without the cold period, the plants don't flower, or flower late.
Term
Winter solstice
Definition
The day with the shortest photoperiod in the northern hemisphere. The sun's rays hit the Tropic of Capricorn at a 90º angle. December 22.
Term
Winter wheat
Definition
Wheat that is planted in the fall. Gives it a head start in the spring. Extends the growing season. Not as profitable as corn or soybeans in terms of sale, but has yield-improving effects on rotations. Adds soil structure, diversity, and winter cover. More successful than spring wheat in Ontario. The crown survived the winter. Soil fertility and an early planting date enhances survival numbers; crown is larger.
Term
Xylem
Definition
Tubes that deliver water and nutrients from the roots to the leaves. Encased in the endodermis.
Term
Yam
Definition

Dioscorea species.

A tuber crop. Require 1150 mm - 1200 mm of wter. There are 40 cultivated species with 13 major ones. Grows for 6 - 10 mnths. Requires deep friable soil with good drainage. Propagated by tubers or stem cuttings. Planted in mounds or ridges and supported with stakes. Labour intensive production. Yields 20 - 40 tonnes/ha. Root can be stored fresh for 4 - 18 weeks.

Term
Yautia
Definition
A corm crop. Classified as a root and tuber crop.
Term
Year bean
Definition

aka Phaseolus polyanthus

A hybrid of common bean (Phaseolus vulgaris) and runner bean (Phaseolus coccineus), then back-crossed through runner beans.

Term
Yield
Definition
Depends on the amount of solar energy available, and the efficiency of its use.
Term
Zinc (Zn)
Definition
A micronutrient essential mineral element. Absorbed as Zn2+. C4 plants need more than C3. At high concentrations it interferes with iron uptake, causing iron deficiencies. Its cell function is as an enzyme activator. An immobile element. Deficiency causes broad white bands on older leaves.
Term
Zygote
Definition
A diploid cell created when a sperm combines with the egg cell. Develops into the embryo.
Term
Poinsettia
Definition
 A potted plant. A short-day plant. Grown seasonally. Scheduling is crucial. Growers want them to bloom in mid-winter for Christmas, so they use supplemental lighting in the greenhouse to postpone flowering.
Term
Acai berry
Definition
A superfruit.
Term
Aerenchyma cells
Definition
Cells in a rice plant that allow oxygen to flow to the roots. This is how rice is able to survive in flooded areas.
Term
Aeroponics
Definition
Hydroponics without a root-zone substrate. Very uncommon. Breakage of roots can lead to unsorted nutrient uptake.
Term
African cotton production
Definition
Africa produces 10% - 15% of the world's cotton. Small, marginal farms. Low yielding varieties. An important source of foregin exchange, rural employment, and poverty reduction. Six million people are employed in the cotton industry in West and Central Africa. Government supplies the inputs. Use of outdated techniques and equipment. Insufficient use of fertilizers and overuse of agricultural chemicals. Infrastructure problems.  6% of the cotton is made into products locally.
Term
Agrarian systems
Definition

aka Agricultural Revolution of the Middle Ages in Northwestern Eruope.

1000 AD.

Used animal drawn plows, fallowing, and harrowing. Three field rotation: rye or wheat / peas, lentils, or beans / fallow with peripheral grazing. Improved land preparation, Invention of the scythe allowed for cut and carry systems.

Term
Agriculture
Definition
A symbiotic relationship between humans and domesticated species. Both benefit. Evovled in small steps. Local environments have strong effect on rate and direction of change.
Term
Alliaceae
Definition

aka Alliums

aka Onion Family

Onions, garlic, leeks, and chives. Have a low LAI, so herbicides are necessary. Grown in muck soils to allow for mechanical harvesting and a uniform formation of bulbs.

Term
Almeria
Definition
A region in the Mediterranean that has the highest concentration of high-tech greenhouses in the world.
Term
Alsike clover
Definition
A forage crop. Found in established pastures.
Term
Alstroemerias
Definition
A cut flower crop.
Term
American upland cotton
Definition

Gossypium hirsutum

A New World cotton species. Has a short staple: 10 mm - 15 mm. Accounts for 80% of world cotton production. High yielding. Needs more water and more fertilizers. Prone to pets. Suitable for deep, heavy soils with good irrigation.

Term
Annual pasture
Definition
A pasture that is reseeded every spring. Include oats, barley, corn, or cover crops. Seeding costs are high.
Term
Antioxidants
Definition
Chemicals that destroy reactive oxygen species.
Term
Apiaceae
Definition

aka Umbellifera

aka Parsley Family

Carrots, celery, parsnips, drill, and parsley.

Term
Apple
Definition
In the family Rosaceae, there are 15 Mallus species. Produced worldwide. Second most valuable fruit crop in Canada. The area of apple orchards peaked in the 90s in Ontario. In 2012 produciton suffered due to an early warm spring. Cold-hardy. Minimum temperature is -34ºC. Susceptible to apple scab, a fungal disese. There are many dwarfing rootstock available, such as M26. Cultivar, soil, water, and rootstock play a role in final tree size. Planted in low, medium, or high tree density. Training systems are used. There are self-fertile as well as self-incompatible cultivars. Cultivars may be diploid, triploid, or tetraploid.
Term
Apricot
Definition

Prunus armeniaca L.

Family Rosaceae. Self-fertile. Rootstocks are used. A stone fruit. Tree is a maximum of 3.5 tall. Mostly self-fertile and do not require pollination. Chilling requirement of 400 - 1000 hours.

Term
Arid rice system
Definition
Sustained with irrigation. Found in Pakistan, Iran, Inia, and Egypt.
Term
Asparagus
Definition
A perennial horticultural crop. Diecious. Male plants are more productive because they produce more carbohydrates. The crown is vegetatively propagated. Deep-rooted.
Term
Asteraceae
Definition

aka Copositae

aka Sunflower Family

Lettuce, endive, globe artichoke, Jerusalem artichoke, and sunflowers.

Term
Azaleas
Definition
A potted plant.
Term
Azolla
Definition
An aquatic plant that improves soil fertility in aquatic rice systems. Fixes nitrogen. There are 70 kg/ha.
Term
Bacterial blight
Definition

Xanthomas campestris

A disese that affects rice. A fungus.

Term
Bales
Definition
A method of hay storage for hay with a moisture content 14% - 19%. Drying the hay down to this level is the hardest part. If hay is baled with too high of a moisture level, microbes can produce enough heat to set the hay on fire!
Term
Bare-root transplant
Definition
Seedlings are grown in a field and moved to a separate place bare-rooted.
Term
Bartlett pear
Definition
A chance seedling pear cultivar discovered in 1799.
Term
Beets
Definition
A biennial horticultural crop. Direct seeded. Long-day plant.
Term
Begonias
Definition
A potted plant. Grown in a weekly program.
Term
Berry cropping systems
Definition
A classification of fruit crops. Berry species each have a unique set of parameters in order to be successful. Further classified by geographic location, field/greenhouse, and crop use (fresh market/processing).
Term
Biological control
Definition
An IPM action. Release of or creation of an environment favourable to beneficial organisms and/or natural enemies of pests.
Term
Biotillage
Definition
Use of plants to till the soil. For example, oilseed radish.
Term
Black currant
Definition

Ribes nigrum L.

Very high in vitamin C.

Term
Black raspberry
Definition
Rubus occidentalis L.
Term
Blackberry
Definition

Rubus ursinus Cham & Schlect.

A bramble. It is closely related to boysenberry, loganberry, younberry, and dewberry. Self-fertile. Some cultivars are polyploid, up to 12 n!

Term
Bloom
Definition
The fourth and final stage in forage development. The seeds are developed.
Term
Blue-green algae
Definition
Improves soil fertility in aquatic rice systems. Fix nitrogen. There are 70 - 110 kg/ha.
Term
Blueberry
Definition
Family Ericaeae. The most valuable fruit crop in Canada. Has the most area of any other fruit crop in Canada. There are highbush and lowbush blueberry cultivars. Originated in North America. A superfruit. High in biotin, riboflavin, manganese, iron, and antioxidnts. Require soils 4.5 - 5.0 pH. Self-fertile.
Term
Boll
Definition
The fruit and harvested part of cotton. Susceptible to leaf feeding and boll worms at this stage in development.
Term
Boot
Definition
The second stage in forage development. The target stage for harvest. Late boot stage is preferred.
Term
Boysenberry
Definition
A bramble. Related to blackberries. Self-fertile.
Term
Bradford Marsh
Definition
A region in Ontario with muck soils.
Term
Brambles
Definition
Family Rosacea. Rubus species. Blackberries, raspberries, boysenberries, loganberries, younberries, and dewberries. Produced in northwestern US. Ever-bearing varieties exist, allowing for production over a long period of time in low-tech greenhouses. Require low temperatures.
Term
Brassicaeae
Definition

aka Cruciferae

aka Crucifers

aka Mustard Family

aka Cole crops

Cabbage, cauliflower, broccoli, radish, kale, kohlrabi, ruabaga, and collards. Biennials. Transplanted. Nutritious and contain anti-cancer compounds. Very in morphology and colour even within crops. Insect control is a big problem. The smell of the crops attrats Lepidoptera species. There are few herbicides, so hand-weeding may be required.

Term
Breast collar
Definition
When a farming implement is attached to a breast collar of a draught animal. The chest of the animal is doing the pushing.
Term
Broccoli
Definition
A Brassicaeae horticultural crop. Shallow-rooted.
Term
Brown rice
Definition
Paddy rice with the hull removed. Still contains the bran.
Term
Brown rot
Definition
A fungal disese that affects cherries, peaches, and nectarines close to harvest.
Term
Bt
Definition
A transgene of a protein from the bacteria Bacillus thuringensis, which is toxic to insencts. May resulti in increased insect resistance to the protein. One solution is to have the gene activate only as the insect eats the foliage. Conterfiet Bt cotton exists.
Term
Bunchgrasses
Definition
Grass species that have grazing tolerance.
Term
Bunkers
Definition
An air-tight method of hay storage. Hay is packed into a bunker with an air-tight cover. The hay ferments.
Term
Cabbage
Definition
The most important Brassicaeae crop. Shallow-rooted. Adapted to cold storage. Includes green, savoy, and red. Savoy cabbage is the most resistant to frost.
Term
Calgene
Definition
The company that first invented Roundup Ready soybeans in 1985. It was bought out by Monsanto in 1997.
Term
Canada bluegrass
Definition
A wild grass. May be used for forage. Found in natural unimproved pastures.
Term
Candle
Definition
The fourth stage in cotton boll development.
Term
Carnation
Definition
A cut flower crop.
Term
Carrot
Definition
The most important Apiaceae crop. A biennial. Direct seeded. Intermediate-rooted. The most significant vegetable crop in Canada for fresh markets. Grown in muck soils, allowing for mechanical harvest and uniform root formation. Can be stored cold.
Term
Cauliflower
Definition
A Brassicaeae crop. The harvested part is an immature inflorescence with thousands of flower meristems. It turns yellow if exposed to sunlight, so the wrapper leaves are tied over the haed of the cauliflower. Shallow-rooted.
Term
Celery
Definition
An Apiaceae crop. A biennial. Transplanted. Shallow-rooted.
Term
Chance seeding
Definition
A classification of fruit crops. Cultivars that were found by chance from seed of unknown parentage. Example: Delicious apples, McIntosh apples, Bartlett pear, and Elberta peach.
Term
Chemical control
Definition
An IPM action. Insect pheremones, biologically produced toxins, or pesticides are administered.
Term
Cherries
Definition
Family Rosacea. There are sweet cherries and sour cherries. Susceptible to brown rot fungus. Some dwarfing rootstock is available. Grown in Hardiness zone 5b, near Lake Ontario.
Term
Chinese cabbage
Definition
A long-day horticultural crop.
Term
Chives
Definition
An Alliaceae crop.
Term
Climatic zones
Definition
Zones in Ontario based on the number of frost-free days in a year. Not a direct measurement of temperature regime. Frost is defined as a temperature below 0ºC.
Term
Coire
Definition
A biodegradable root-zone substrate. Coconut shell fibre.
Term
Cold frames
Definition
A type of protected agriculture for hardening. Utilizes natural light.
Term
Cold storage
Definition
A theoretical third option for hay storage other than bales and air-tight storage. It is virtually never used.
Term
Collards
Definition
A Brassicaeae crop.
Term
Container nursery
Definition
A system for nurseries that uses containers on gravel. 30% of nurseries in Ontario. More prevalent in BC. A type of protected horticulture. Utilizes natural light. Can market at any time of the year. Roots are left intact. Higher plant density is possible. No rotation issues. Produces more uniform plants. Product is lighter and lasts longer. Good soil on the site is not required, just good drainage. Roots more susceptible to frost and tipping over in the wind. Irrigation necessary. Limited root system and tree sie. Nutrients must be monitered. Inludes unprotected and protected containers. Produces ornamental grasses, deciduous shrubs, evergreens, caliper trees, roses, and vines.
Term
Continuous grazing
Definition
A type of pasture system. The least amount of labour. The poorest results. Animals are on pasture for as long as the pasture can handle. Initial gains are good because of selective feeding, but as the season progresses, forage quantity, quality, and palatability decline. Overgrazing and excessive trampling of forage.
Term
Controlled atmosphere storge (CA):
Definition
A type of protected horticlture. Includes natural light.
Term
Conventional breeding
Definition
Uses naturally-occuring mutagenesis germplasm to produce genetic improvement. Has limitations: some traits may have low to non-existant natural frequency, or be difficult to use in a breeding program. Some plants have too long a generation time or are vegetatively propagated.
Term
Cool/warm season crop
Definition
A way of classifying vegetable crops. There are cool and warm season vegetables.
Term
Cool season vegetable
Definition
The edible part is the roots, leaves, stems, buds, or immature flower parts. Frost tolerant. Seeds germinate at cool temperatures. Have shallow roots (exception: asparags). Smaller plants. Wide variation in days to maturity. Stored at around 0ºC and 90% - 95% RH.
Term
Cortland apple
Definition
A sexually bred apple cultivar. A cross of McIntosh and Ben Davis.
Term
Cranberry
Definition

Vaccinium macrocarpon

Family Eriaceae. Originated in North America. A superfruit. High in vitamin C, manganese, vitamin B5, and antioxidants. 20% of world production is in BC (50% of Canadian production). Grown in wetlands or constructed flooded cranberry beds. Require soils 4.5 - 5.5 pH and a water table 0.3 m - 0.8 m from the surface. Flooding protects plants from winter kill and spring frost. Self-fertile.

Term
Creeping red fescue
Definition
A forage crop. Found in established pastures.
Term
Creston aplpe
Definition
A triploid apple cultivar.
Term
Cucumber
Definition
A Cucurbitaceae horticultural crop. An annual. Shallow-rooted. A major fresh market greenhouse vegetable crop. Field cucumbers are bred to by gynoecious. Greenhouse cucumbers are often parthenocarpic and do not taste bitter. Hydroponically in a greenhouse, 3 - 4 crops are produced a year.
Term
Cucurbitaceae
Definition

aka Cucurbits

aka Gourd family

aka Vine crops

Cucumber, pumpkin, melon, and watermelon. The second most important family of vegetable crops (after Solanaceae). Direct seeded or transplanted. Day-neutral plants. Insect pollinated. A major processing vegetables family in ONtario. Have monoecious flowers.

Term
Cultivated oats
Definition
An autopolyploid.
Term
Cultivar selection
Definition
Fruit cultivar selecton for use (processing or fresh markets), picking dates, quality, and disease tolerance.
Term
Cultural control
Definition
An IPM action. Crop rotation, cover crops, cultivation, tillage, mowing, trapping of pests, and destructino of pest habitat.
Term
Currants
Definition
Include white, red, and black currants. Susceptible to powdery mildew and white pine blister rust.
Term
Cut flower crops
Definition
Includes roses, mums, gerbera, carnation, snapdragons, tulips, alstroemeria, daffodils, and lilies. 130 million cut stems are grown in Ontario each year, worth $165 million. Much of the industry has moved to South America.
Term
Cyclamen
Definition
A potted plant. Propagated by seed.
Term
Daffodil
Definition
A cut flower crop
Term
Day-neutral strawberry
Definition
A type of ever-bearing strawberry. Older cultivars produce 3 crops a summer. Newer cultivars produce constantly into the fall.
Term
Dead zone
Definition
An area in the Gulf of Mexico where there is no oxygen due to algae blooms caused by fertilizer run-off and leaching. Causes all the fish to die.
Term
Deep-rooted crops
Definition
Roots are deeper than 60 cm. Asparagus, parsnip, pumpkin, sweet corn, watermelon, and winter squash.
Term
Delicious apple
Definition
A chance seedling apple cultivar discovered in 1870. Requires 3000 CHU minimum.
Term
Dewberry
Definition
A bramble. Related to blackberries. Self-fertile.
Term
Diecious
Definition
Havig separate male and female plants.
Term
Dill
Definition
An Apiaceae crop.
Term
Direct seeded
Definition
A propagation classification of vegetable crops. Includes beets, carrots, onions, radishes, cucurbits, peas, beans, and sweet corn. Inlcudes precision seeding. No transplanting costs. Facilitates seasonal sequential planting. Requires a smooth seedbed and small seeds. Soil crusting is a problem. Can result in non-uniform stand.
Term
Direct seeded rice
Definition
Can be done by hand or with a machine. May be broadcast with a fertilizer spreader.
Term
Dormant season temperature
Definition
A factor in choosing a site for fruit production. Based on the Hardiness Zone map.
Term
Dwarf trees
Definition
Made using dwarfing rootstock. Tree support may be needed. Makes apples more susceptible to fireblight. Allows for a higher tree density, with the same canopy cover.No tree is getting less than 30% of full sunlight. Increased desnsity causes increased costs. Better light penetration causes better coloured and sized fruits. Takes less time to produce fruit. Harvest index is increased. More carhbohydrates are partitioned into the fruit, and less into wood.  Improved pest and disease control. Spraying, fruit thinning, pruning, and fruit picking is easier, saving time and money.
Term
Dwarf varieties
Definition
Produced using conventional breeding for wheat and rice. Has a higher HI. Have a reduced sensitivity to the lant hormone gibberellin.
Term
Dwarfing rootstock
Definition
Rootstock, especially for apples, that produces dwarf trees. How it does this is unknown. May be less cold-hardy than normal rootstocks. Soe have reduced disease tolerance, such as to collar rot and fireblight. Sensitive to wet soils since the root systems tend to be smaller. Needs more attention to fertilization and irrigation.
Term
Early peach
Definition
A mutation peach cultivar that arose from Redhaven peaches.
Term
Eggplant
Definition
A Solanaceae crop. Insect pollinated.
Term
Elberta peach
Definition
A chance seedling peach cultivar discovered in 1870.
Term
Endive
Definition
An Asteraceae crop.
Term
Environmental control
Definition
Done in a greenhouse using computers, outdoor sensors, and indoor sensors. Modifies air temperature, soil temperature, humidity, CO2, and water temperature.
Term
EPSP synthase
Definition

aka EPSPS

The enzyme effected by glyphosate. Required for synthesizing the amino acids phenylalanine, tyrosine, and tryptophan.

Term
Established pasture
Definition
A pasture seeded for the purpose of poasture. May have alfalfa, birdsfoot trefoil, clovers, bromegrass, timothy, reed canary grass, orchardgrass, ryegrass species, and fescue species. Species selection determines yield quantity, quality, and distribution over the season. Succession to less productive species must be avoided through grazing and fertilization management.
Term
European plum
Definition

Prunus domestica L.

It is hexaploid.

Term
Ever-bearing strawberry
Definition
Strawberries that require short days and warm temperatures to flower. Produce flowers and fruit all through the summer. Some are grown in greenhouses. Includes day-neutral strawberries.
Term
Fabaceae
Definition

aka Leguminosae

aka Legume family

aka Bean family

aka Pea family

aka Legumes

Peas and beans. Day-neutral. An important processing vegetable crop, especially peas.

Term
Facultative diapause
Definition
When a pest species can survive periods of low host availability.
Term
Field-grown fresh market vegetables
Definition
Makes $7500 - $15000/ha. Economic threshold is 30 to 60 ha. Low mechanization and capital investment. Higher quality and lower yields than processing markets.
Term
Field-grown ornamentals
Definition
110,000 ha worldwide. Worth $3 billion.
Term
Field nurseries
Definition
A system of nursery. 70% of nurseries in Ontario. Trees can only be marketed in their dormant phase between November and March. There are no leaves on the trees at this time, so there is less transpiration and less water stress. When dug up, the trees lose 90% of roots. Winter kill is less of a risk. Spacing cannot be changed once plants are planted.
Term
Fireblight
Definition
A bacterial disease common in pears, and less so in apples.
Term
Fixed upland rice systems
Definition
Defined, longstanding fields.
Term
Flash flood rice
Definition
Does not elongate when submerged in water, as deep-water rice would. Can survive up to 4 days completely submerged. When the waters recede, the plant is the same size as before, so it doesn't fall over.
Term
Flavr Savr tomato
Definition
A GMO crop developed by Calgene with reduced activity of the PG enzyme that breas down pectin in the cell walls. It should soften slower. Instead the shelf life of the tomato was lengthened. They were not widely adopted by processing or fresh markets. Pesticides, fungicides, and herbicides are used in non-organic operations.
Term
Floatins row covers
Definition
A type of protected horticulture. Utilizes natural light. Inflated plastic covers over rows.
Term
Flood-prone rice systems
Definition
More than 10 consecutive days of deep flooding over 50 cm during crop growth. Direct seeded. Aerobic anaerobic soil. Salinity toxicity an issue.
Term
Forage quality
Definition
Quality forage is defined as having less lignin fibres. It has more available energy. Quality of forages goes down as the plant develops. Low quality feed has less dense energy and needs extensive digestion, however some fibre is needed in the diet for health.
Term
Free-living rhizospheric organisms
Definition
Increase soil fertility in aquatic rice systems. Fix nitrogen. There are 6 - 24 kg/ha.
Term
Free-standing central leader system
Definition
A training system used in low to medium tree density. No support is used, but it may be necessary for scion/rootstock combinations that produce trees with poor anchorage, such as Red Delicious and M26. Semi-dwarf rootstocks are used. Tree size is intermediate to large. Extensive pruning, large canopy. Slower to bear fruit.
Term
Fresh vegetables market
Definition
Can be greenhouse or field-cultivated. Differ from processing vegetable markets. Quality and appearance of product is more important. Management intensity is greater. Greater use of pesticides and fungicides. Market is a free market system. Growers may market themselves or sell to packagine/shipping wholesalers. Chain stores buy from the wholesalers, who deal a large variety of products. Only small amounts of a wide variety of vegetables are needed. Fresh vegetables are demanded all year, but can only be harvested once a year in Canada. Greenhouses and importation are solutions to this problem.
Term
Frost
Definition
Defined as -2ºC for corn and -3ºC for soybean.
Term
Frost seeding
Definition
Planting cereal into ground that still has frost. Caused increased yields, decreased protein, earlier heading, lower harvest moisture, stand decrease, and weight increase. Plants are advanced in development.
Term
Fruit thinning
Definition
Use of chemicals that increase rate of flower or abortion or fruit drop, or by hand removal of fruits at flower clusters. Optimizes vegetative/reproductive growth ratio. Optimizes the number of fruits on a tree so that the fruit has better size and taste. Too many fruits results in smaller, less sweet fruits.
Term
Garlic
Definition
An Alliaceae crop. Clones are vegetatively propagated.
Term
Gene Revolution
Definition

aka Biotechnology Revolution

1990 - present

Bt and herbicide resistant crops developed. Bio-fortification. Higher seed cost, but lower production costs Higher farm income. Increased resistant weeds. Questionable safety and sustainability. Cultural acceptability issues.

Term
Genetic control
Definition
An IPM action. Use of pest resistant plant varieties.
Term
Genetic improvement
Definition
Accounts for 50% of cropping system improvement (the other half is management improvement). The genetic variation is improved. Gene recombination, selection, and field testing. Can use conventional, mutation,  or transgenic breeding.
Term
Genetically Modified Organisms (GMO)
Definition

aka Transgenic plants

aka Genetically engineered plants

An organism generated using in vitro mutagenesis. They are used extensively worldwide. 160 million ha are planted with GMOs worldwide. Major crops are soybean, corn, cotton, and canola. There is some concern that they will have health effects.

Term
Genuity Roundup Ready 2 Yield
Definition
A Roundup Ready GMO released by Monsanto after the patent on Roundup Ready expired. Includes the Roundup Ready gene, plus a transcriptional promoter and an antibiotic. Doesn't actually that much difference from Roundup Ready.
Term
Geraniums
Definition
A potted plant.
Term
Gerbera
Definition
A cut flower perennial crop that is grown hydroponically from a rhizome. Sometimes soil-grown. Propagated by seed.
Term
Germplasm
Definition
Genetic variation. Need to alter genetic makeup of an organism for genetic improvement.
Term
Gibberellin
Definition
A plant hormone that influences the elongation of a plant stem. Dwarf varieties of wheat and rice have reduced sensitivity to this hormone.
Term
Ginseng
Definition
A sector of Canadian horticulture.
Term
Glass greenhouse
Definition
Glass is more expensive than plastic. Used when maximizing winter light is crucial, the grower has a lot of capital, and fuel costs are less critical. Glass is replaced every 20 years. it is less insulating than plastic.
Term
Globe artichoke
Definition
An Asteraceae crop. A perennial. In a different genus than Jerusalem artichokes. The edible part is an immature inflorescence.
Term
Glucosinolates
Definition
Present in canola and cabbage. It is what attracts cabbage moths.
Term
Glyphosate
Definition

aka Roundup

Originally invented in 1956 in Germany. An herbicide that inhibits the plant enzyme EPSPS. Monsanto owns the patent. Roundup Ready plants are not affected by it. It can cause cancer and health problems if consumed by mice, and presumptively humans as well.

Term
Golden Rice
Definition
A GMO rice cultivar that has vitamin A.
Term
Gooseberry
Definition

Ribes grossularia L.

There are green and red. Susceptible to powdery mildew and white pine blister rust. Self-fertile.

Term
Gossypium barbadense
Definition
A New World cotton species. Has a long staple 20 mm long.
Term
Grape
Definition

Vitris labrusca L. originated in North America.

Vitris rotundifolia Michx. and Vitris vinifera L. are hybrids.

Family Vitaceae. Vitris vinifera is commonly grown on a rootstock for phylloxera and nematode resistance. The most important and most widely grown deciduous fruit. Grown on every continent. 52 million tonnes are produced each year worldwide, 50% of this in Europe. It is one of the oldest cultivated crops. France is the standard for grape and wine production. There are some cold-hardy cultivars grown in the Niagara region and Lake Eerie, controlled by the VQA. Cultivars differ in colour, sie, seed, use, and origin, many corresponding with a type of wine. The five uses for grapes are table, raisins, wine, juice, and processing. Area of vineyards in Ontario decreased in the 80s and leveled off. The change in the value of grapes was not proportional to this change. Becoming the most valuable fruit crop in Ontario. The only temperate fruit crop that is not insect pollinated. It is wind pollinated. Limited to Hardiness zones 7a, 7b, and 6b. Minimum temperature of -24ºC.

Term
Grazing tolerance
Definition
A characteristic of all forage crops. Must tolerate having up to 75% of its above ground matter eaten, as well as being trod on. The critical growing point is at or near soil surface. Has unelongated internodes. Plants with grazing tolerane include bunchgrasses, rhizomatous grasses, and stoloniferous legumes. Plant regrowth comes from the basal leaf area and energy stores in the stem base, rhizomes, roots, or stolons.
Term
Greenhouse
Definition
A type of protected horticulture. A glass or plastic building. 70% of the cooling is done by plant transpiration. The other 30% is venting, screening, and fans. Watering is timed to co-ordinate with light irradiance. There are 280,000 ha of greenhouses worldwide. 140,000 ha in Asia, 100,000 ha in the Mediterranean, 20,000 ha in Europe, and 20,000 ha in the Americas.
Term
Greenhouse fresh-market vegetable
Definition
A sector of Canadian horticulture. 173,000 ha worldwide. Industry is worth $25 billio. Has high capital investment: glass/plastic structures, lighting, heating, ventilation, shading systems, nutrition, automation, and technology can cause $600 thousand - $1 million per acre. Produces $700 thousand -$800 thousand per hectare. The average operation is 9 acres. May be hydroponic (high use of fertilizer). Technoogy changes quickly and producers have to replace everything every 5 years to keep up with competition. These systems have the highest management insensity. 80% of Canadian greenhouse products are shipped to the US. Pesticide and fungicide use is minimal. Herbicide use is non-existant. Produce a higher quality product than field production.
Term
Greenhouse ornamentals
Definition
107,000 ha worldwide. Industry is worth $21 billion. Produces cut flowers, potted plants, bedding plants, transplants, and hanging baskets. Scheduling is crucial for flowering plants. Automatic precision seeders and plug transplanters may be used. Over 625 million peding plants/transplants are grown in Ontario a year producing over $180 million/year.
Term
Growing season temperature
Definition
A factor in choosing site for a fruit crop. Some cultivars may be killed by low temperature. Larger day vs. night temperatures result in better pigment production in fruit.
Term
Half-truth method
Definition
When people present only facts and ideas that support their personal values and goals, excluding the other half of the story that does not support it. Used during the debate between pro and anti-GMO activists.
Term
Hand-picking
Definition
A more labour intensive way to harvest cotton. Must be picked multiple times a year. Yields a higher quality product. Each boll must be plucked one at a time. 20 plnts harvested in 9 minutes. Much slower than machine harvest.
Term
Hanging baskets
Definition
A way to maximize production in a set amount of greenhouse space.
Term
Hardening
Definition
Before transplanting, seedlings must be healthy, compact, and have good root development.
Term
Hardiness Zone map
Definition
A map based on minimum temperatures of a region.
Term
Heading
Definition
The third stage in forage development. Seed head is emerging.
Term
Herbicides
Definition
There are few herbicies for horticultural products; the acreage is too small to make devlopment profitable.
Term
Herbs
Definition
A sector of Canadian horticulture.
Term
High altitude rice systems
Definition
Small terraced plots in mountainous areas. Found in the Philippines, Indonesia, Thailand, and India. Indica varieties are used.
Term
High-tech greenhouse
Definition
Capable of being heated. Used in cooler regions. Has a venting system to allow cooling during hot weather. May have auxiliary cooling such as a fan system. Most high-tech greenhouses use a hot water heating system. There are also steam systems.
Term
High tree density
Definition
Over 500 trees /acre. Rootstocks are dwarfing. Tree support is needed. Requires special training. Only M26 or smaller rootstocks are used.
Term
High Yielding Variety (HYV)
Definition
Developed during the Green Revolution. Often a dwarf species. For rice, there are fewer tillers, fewer grains per panicle, require good cultivation practices, and has higher grain yield.
Term
Highbush blueberry
Definition

Vaccinium corymbosum L. and Vaccinium australe

Cultivated blueberries. 50% of Canadian blueberry production by volume. Grown mainly in British Columbia. Some acreage in Ontario. It is tetraploid.

Term
Honey
Definition
A sector of Canadian horticulture.
Term
Horseradish
Definition
A biennial crop. The root is vegetatively propagated.
Term
Horticulture
Definition
4% of all farms in Canada are horticultural. The agricultural sector with the most growth in the last 30 years. Ontario has the most horticulture (24% of it's agriculture), follwed by Quebec and British Columbia. The total area of horticulture is decreasing. Manitoba and PEI and increasing in horticulture. Manitoba's increase is due mainly to Alliums.
Term
Hot caps
Definition
A type of protected horticulture. Utilizes natural light. Plastic caps are placed over individual plants.
Term
Hot water system
Definition
A heating system for high-tech greenhouses. Pipes containing hot water. It is more exact than a steam system and temperature can range from 0ºC to 100ºC.
Term
Hothouse
Definition
A type of protected horticulture. Excludes natural light. Used for growing mushrooms, rhubarb, and sprouts.
Term
Hybrid rice
Definition
Challenging to produce because rice is self-pollinating. Male sterlie plants are strip-intercroped with regular plants. "Pure lines" are crossed. There are crosses of hybrids called double crosses. Yields are up to 35% higher. Require good management practices, especially fertilizer. Without this, yields are lower. Cannot save seed for a second crop. Economically viable if management is above 60%. Resistant to pests, disease, and lodging.
Term
Hybrid vigour
Definition
In certain crops, hybrids perform better than true-breeding parents. However, more fertilizers are needed to create this increase.
Term
Hybrid
Definition
A method of creating dependency on seed companies. Seed companies sell only hybrid cultivars. Saving seed will do the farmer no good; the progeny will have poor genetics, so growers have to come back to the seed company every year.
Term
Improved pastures
Definition
Natural pastures that were reseeded, fertilized, mechanically clipped, harrowed, weeds controlled, and/or fenced to improve productivity. Species were not removed, just made less prevalent.
Term
In vitro mutagenesis
Definition
Produces transgenic germplasm used in transgenic breeding. Produces GMOs. DNA is isolated, altered, and reintroduced to the plant. Mutagenesis occurs in a test tube. Process is directed towards a secific gene. Sexual compatibility is not required, dramatically expanding the gene pool. Can overcome some of the limitations of conventional breeding. First developed as a scientific tool, then later put to use in breeding.
Term
In vivo mutagenesis
Definition
Produces natural-lie germplasm used in mutation breeding. Plant cells, tissues, organs, or whole plants are treated with a mutagenizing agent. Incrases rate of mutagenesis. Can overcome some of the limitations of conventional breeding. Used extensively for ornamental plants.
Term
Inulin
Definition
An indigestible carbohydrate found in Jerusalem artichokes. Used by diabetics for its sweet taste.
Term
Integrated pest management (IPM)
Definition
A system of complimentary mangement actions including biological control, cultiral control, sanitation, chemical control, genetic control, and legal quarantines.
Term
Intermediate rooted crops
Definition
Crops where the roots go down 30 cm - 60 cm. Beans, carrots, muskmelon, peppers, tomatoes, and zucchini.
Term
Irrigated rice systems
Definition
Level, shallowly flooded fields with water control. Direct seeded or transplanted.
Term
Japanese plum
Definition
Prunus salicina
Term
Javanica rice
Definition
A minor group of rice cultivars.
Term
Jerusalem artichoke
Definition
An Asteraceae crop. It is in a different genus from globe artichokes. The edible part is an underground stem. It contains inulin.
Term
Jonagold apple
Definition
A triploid apple cultivar.
Term
June-bearing strawberry
Definition

aka common strawberries

Require short days and warm temperatures to flower. After harvest, flowering stops and the plant is vegetative, putting out runners. Will flower in long days if the temperature is around 15ºC. Grown in central California.

Term
Kalanchoe
Definition
A potted plant. Grown on a weekly program.
Term
Kale
Definition
A Brassicaeae crop. One of the most nutritious vegetables.
Term
Kentucky bluegrass
Definition
A forage crop. Found in natural unimproved pastures.
Term
Kohlrabi
Definition
A Brassicaeae crop.
Term
Labour
Definition
A major cost in horticultural systems. Vegetable production is very labour intensive. A sufficient and skilled workforce is needed. Wages in Mexico and Chile are much lower.
Term
Lake Eerie's north shore
Definition
A major grape growin region of Ontario. The shallow waters of Lake Eerie have the most sunshine in all of Canada, caussing excellent ripening conditions for full-bodied wines.
Term
Lathhouse
Definition
A type of protected horticulture. A shading structure over the plants. Utilizes natural light, but reduces it. Use in ginseng, hydrangea, and azalea production.
Term
Leafy
Definition
The first stage of forage crops.
Term
Leek
Definition
An Alliaceae crop. Transplanted.
Term
Lettuce
Definition
The most significant Asteracea crop. An annual. Transplanted. A long-day plant. Shallow-rooted. A significant amount of the world's lettuce is grown in Canada.
Term
Leveling
Definition
To make a field flat. Rice yield is highly effected by field flatness.
Term
Life cycle
Definition
A way of classifying vegetable crops. Includes annuals, bioennials, and perennials.
Term
Light
Definition
The primary factor governing greenhouse production. Winter production is significantly lower than summer production in greenhouses.
Term
Lilies
Definition
A cut flower crop or potted plant. Grown seasonally. Scheduling is crucial.
Term
Liner
Definition
A young nursery stock plant generated form seed, cutting, grafting, budding, or tissue culture.
Term
Loganberry
Definition
A bramble. Related to blackberries. Self-fertile.
Term
Long standing flood water rice systems
Definition
Found in Bangladesh, Thailand, India, and Vietnam. Use deep water rice varieties.
Term
Low-tech greenhouse
Definition
Has no heating system. Used in warmer regions. Has a venting system to allow cooling in hot weather.
Term
Low tree density
Definition

aka Traditional planting density

Up to 125 trees/acre. Semi-vigorous rootstocks used such as M7 or MM106. Low cost of establishment. Les pricise management. High pruning, spraying, and harvesting costs. Large equipment needed. Takes a long time to come into bearing. Young trees must be defruited for framework to develop.

Term
Low tunnels
Definition
A type of protected horticulture. Utilizes natural light. Plastic tunnels are placed over the plants. There are 250,000 ha of low tunnels worldwide.
Term
Lowbush blueberries
Definition

aka Wild blueberries

Three species, including Vaccinium angustifolium L. Grown mainly in Atlantic Canada.

Term
MacIntosh apples
Definition
A mutation in apples discovered in 1886. The tree has been asexually propagated since that time.
Term
Male sterility
Definition
In the late 1970s, a male-sterile form of corn was developed to prevent the spread of genes. It also made the corn very susceptible to Southern corn leaf blight. Male-sterile rice is used to produce rice hybrids.
Term
Malling-Merton and Malling (MM)
Definition
A series of rootstocks named fter the research stations they originated from in England.
Term
Management improvement
Definition
Acounts for 50% of cropping system improvements (the other half is genetic improvement). Field testing.
Term
Maple products
Definition
A sector of Canadian horticulture.
Term
Match-head square
Definition
The second stage in cotton boll development. Susceptible to sap-sucking pests including mites, jassids, thrips, and aphids.
Term
Mechanical harvest (cotton)
Definition
There are cultivars bred specifically for mechanical harvest Chemical defoliants are used first to remove leaves. Less labour intensive than hand picking. Yields a lower quality product than hand picking. 1200 plants harvested in 30 seconds. Much faster than hand-picking.
Term
Mechanical harvest (forage)
Definition
A harest method for forage crops. More common than grazing, especially in dairy systems. In Canada livestoc must be housed indoors through the winter, so some mechanic harvest is necessary. Feed is more consistent. More expensive than grazing. Up to 5 cuts are made per season. Yield increases, and the nutrition of the crop changes the more often it is cut. Must be stored afted harvest: storage methods include bales, air-tight sealing (wrapped bales, bunkers, silos), and cold storage.
Term
Mechanzation Revolution
Definition

1860

Invention of motors and mineral fertilizers. Railways reduced transport costs, improving agricultural markets. Use of fertilizers including sewage, superphosphates, guano, and Haber process products (ammonia, nitrate, nitrite). Steam tractors were invented and horses were no longer used by 1930. Internal combustion engines invented in 1940. Hybrid corn was invented in 1930. Steam plows lead to removal of hedges and enlarged fields. Fewer farm workers were required, freeing up labour for factories and mines during the Industrial Revolution.

Term
Meadow fescue
Definition
A forage crop. Found in established pastures.
Term
Meadow foxtail
Definition
A forage crop.
Term
Medium tree density
Definition
125 - 400 trees/acre. Semi-dwarf or dwarf rootstocks are used such as M7, M26, or M9. The most common density in Ontario for apples. Insect and disease control costs are reduced. More sunlight enters the canopy; better fruit size and colour. More intensive than low tree density. Establishmen is higher than low density. Precise management is required (additional skill). Exacting training and shaping is required.
Term
Melon
Definition
A Cucurbitaceae crop.
Term
Milled rice
Definition

aka White rice

Hull and bran are removed.

Term
Minimum chilling requirements
Definition
A factor in choosing a site for fruit production. Temperatures 0º C - 10ºC are required to overcome bud dormancy, an adaptation to prevent growth before spring comes. This is the reason fruit and nut production is limited to between 30 and 50 degree latitudes.
Term
Mob grazing
Definition
A type of pasture system. The field is flooded with livestock so that it is evenly grazed.
Term
Mode of pollination
Definition
A way to classify fruit crops. All temperate fruit crops are insect pollinated except for grapes, which are wind pollinated. Presence of pollinators is essential for fruit yields. Honey bees and natural pollinators.
Term
Modern Variety (MV)
Definition
Developed during the Green Revolution. Focuses on grain rather than straw and leaves.
Term
Monoecious flowers
Definition
Separate male and female flowers on the same plant. Only female flowers can bear fruit. Cucurbitaceae have monoecious flowers.
Term
Monophageous
Definition
Pest species that feed exclusively on one crop species. For example cotton. Few species are monophageous.
Term
Monsanto
Definition
A company which owns Roundp Ready and Flavr Savr GMOs.
Term
Muck soil
Definition

aka Organic soil

Found in the Bradford Marsh. Feels spongy to walk on. Tile systems used to drain soil or put water into the field, controlling the water table to control the rate of oxidation.

Term
Multispecies grazing
Definition
A type of pasture system. More than one species of livestock are grazed in the sam efield. Differing grazing habits result in more rounded selective grazing. Example: cattle hate thistles, but goats love thistles.
Term
Mums
Definition
A cut flower crop or potted plant. Has four to five crops per year. Soil is used, not hydroponics, even in greenhouses, bcause it would be too much work to dismantle it every time. 4 - 5 crops produced a ear. When potted, grown in a weekly program.
Term
Muskmelon
Definition
An intermediate-rooted crop.
Term
Mutagenesis
Definition
Processes resulting in a change in DNA sequence in an organism. Can b naturally occuring, in vivo, or in vitro.
Term
Mutation breeding
Definition
Uses natural-like germplasm to produce genetic improvement. Uses in vivo mutagenesis.
Term
Mutations
Definition

aka Sports

A classification of fruit crops. Cultivars that aros from mutations of existing cultivars. Example: Redcort Cortland apple, Early Redhaven peach, and Redspur Delicious apple.

Term
Mutsu apple
Definition

aka Crispin

A triploid apple cultivar.

Term
Natural germplasm
Definition
Produced from naturally-occurriing mutagenesis. Used in conventional breeding. Includes dwarf wheat, canola, disease-resistant grain, determinant tomatoes, nectarines, polyploids, and hybdrid crops. Found in areas where the crop originated.
Term
Natural-like germplasm
Definition
Produced from in vivo mutagenesis. Used in mutation breeding. Includes ornamental colour, fruit colour, canola oil content, and polyploids. Useful for vegetatively propagated crops or crops with a long generation time.
Term
Natural unimproved pasture
Definition
A type of pasture system. A complex mix of speccies influenced by growing conditions, weather, and animals. Kentucky bluegrass, Canada bluegrass, and redtop grass. Grazing is best in the spring and turns poor past June. Can exist for up to 30 years.
Term
Naturally-occuring mutagenesis
Definition
Produces natural germplasm that is ued in conventional breeding.
Term
Neck yoke system
Definition
When a farming implement is drawn by a collar on a draught animal's neck. The shoulders of the animal are doing thhe work.
Term
Nectarines
Definition
Plums with a mutant gene that prevents trichome (hair) formation on the surface of the fruit.
Term
Nerica
Definition
A cross between sativa and glabberima rice. An upland rice. Can be intercropped. Resistant to local stresses of Africa, weeds, and lodging. Has rapid growth and a good quality, non-shattering grain. High yielding.
Term
New World Cotton
Definition
Includes Gossypium hirsutum, and Gossypium barbadense. Originated in Pre-Columbian Americas.
Term
Niagara Peninsula
Definition
A major grap growing region in Ontario. The Niagara escarpment and falls provides ideal cool-climate conditions for wine production.
Term
Norfolk 4 Course Rotation
Definition
Invented in the late 1600s in th UK. Common during the 1800s. Wheat/turnips (for winter feed)/barley with clover and ryegrass undersown/clover or ryegrass. Increases quality and quantity of animal feed and manure. Increases cereal yields.
Term
North American plum
Definition
Includes seven Prunus species.
Term
Nurseries
Definition
Total area is decreasing, but average size of a nursery is increasgin. Includes container systems, pot-in-pot systems, and field-soil systems. Nursery stock is sold to retain, fruit growers, landscapers, garden centres, mass merchants, other nurseries, and to the public.
Term
Nutritional content
Definition
A way of classifying vegetable crops.
Term
Old World Cotton
Definition
Includes Gossypium herbaceum and Gossypium arboreum. Accounts for 5% of world cotton production. Originated in Asia. Cultivated in Mesopotamia and Rome 400 BC - 600 BC. Drougt resistant. More pest resistant. Low yields. Shorter staple length. Suitable to shallow, sandy soils with little irrigation.
Term
Oligophageous
Definition
Pest species that feed on a limited range of hosts. Example: pink bollworm.
Term
Onion
Definition
The second most important vegetable for fresh markets (after tomatoes). A biennial. Direct seeded, transplanted, or the sets are vegetatively propagated. Shallow-rooted. Well suited to cold storage, allowing for gradual marketing. Used to spice up foods. Contains fibre, vitamin A, vitamin B6, and potassium. Has cardioprotective benefits and enhances iron uptake.
Term
Orchard
Definition
A good orchard has trees allotted to fill all the space, precocious flowering, optimized light distribution in the tree (factors for this include rootstock, planting density, training, and pruning), good vegetative/reproductive growth balance, access for orchard operations (pesticide penetration), and well-developed integrated pest management.
Term
Organic cotton
Definition
A small industry. Uses rotations, intercropping, legumes, seed treatments, soil fertility, land preparation, and in some areas animal traction. Breeding focused on pest and disease resistance rather than fibre quality. Increased biodiversity, eco-balance, less pollution, less health risks, soil fertility, lower costs of inputs. Cotton sells for a higher price, but still not as profitable as conventional cotton.
Term
Organic soil
Definition

aka Muck soil

20% - 70% organic matter. pH is 5.5 - 6.8. It is not tilled, to reduce oxidation. The water table is maintained close to the surface with a tile and die system. Often deficient in K. Susceptible to wind erosion.

Term
Ornamentals
Definition
A sector of Canadian horticulture. Includes flowers, saplings, Christmas trees, and sod.
Term
Overgrazing
Definition
When a forage crop is grazed too much. Reduces basal leaf area, deleting energy stores in stem bases, rhizomes, roots, and/or stolons, and reduces depth resulting in weak, drought tolerant plants.
Term
Overwintering
Definition
A method of protecting unprotected container nursery plants from winter frost. Depends on the temperatures of the winter. Mild winters get no overwintering technique. For medium intensity winters, a plastic greenhouse cover is erected over the plants. For harsher winters, the plants are turned on their side and burried in wheat straw.
Term
Ozone layer
Definition
A layer of ozone in the atmosphere that protects us from UV rays. It is destroyed by CFCs. Because of banning CFCs, the hole in the ozone layer is filling in. If we hadn't banned them, the whole ozone layer would have ben gone by 2040.
Term
Parsley
Definition
An Apiaceae crop. Very nutritious, yet people often use it as a garnish and don't eat it.
Term
Parsnip
Definition
An Apiacea crop. A biennial. Deep-rooted.
Term
Parthenocarpic
Definition
Seedless and do not require pollination. Greenhouse cucumbers are often parthenocarpic.
Term
Pasture grazing
Definition
A method of forage crop harvest. In Ontario it is less common than mechanical harvest, but very popular worldwide. Less expensive than mechanical harvest. Livestock harvest forage crops. Livestock are self-propelled, self-replicating solar energy collectors that harvest and convert forage crops into human-consumable energy forms while distributing manure to fields. Potentil to be very productive. Pasture systems includ natural unimproved pasture, established pasture, improved pasture, and annual pasture.
Term
Patenting lifeforms
Definition
A controversial subject. Provided an incentive for companies to get involved with developing GMOs. Creates an atmosphere for plundering of farmers.
Term
Peaches
Definition

Prunus persica L.

Family Rosaceae. Originated in China. Frost sensitive. Minimum temperature is -24ºC. The buds are killed at temperatures below -3ºC. Grown in the Niagara region for the lake's climatic warming effect. Susceptible to brown rot. The first trangenic fruit was a peach resistant to plum pox virus. The area of peach producion in Ontario is decreasing because reduciton of the processing industry. Self-fertile. Rootsotck is used.

Term
Pears
Definition

Pyrus species.

Family Rosacea. Susceptible to fireblight, but thhere are some tolerant cultivars. Dwarfing stock is available. One of the most recognized fruit crops of Canada. Cold-cardy. Self-incompatible.

Term
Peas
Definition
A Fabaceae crop. An annual. Direct seeded. Self-pollinating. Planting is scheduled using the Degree Day method. Seeding day is critical to avoi hot, dry weather at flowering. Need 450 D to flower. 720 - 780 DD for early peas. 940 - 1000 DD for late peas. Flowering is at the same time for both, but fruit development is longer for late peas, resulting in higher yields. Some cultivars are tetraploid.
Term
Pecans
Definition
Originated in North America.
Term
Peppers
Definition
A Solanaceae crop. An annual. Insect pollinated. Intermediate-rooted crop. One of the most important greenhouse vegetables in Ontario (along with tomatoes). Red bell peppers have 9 times more lycopene and 2 - 3 times more vitamin C than green or orange bell peppers. Grown hydroponically in greenhouses. 1 crop is produced a year.
Term
Perennial ryegrass
Definition
A forage crop. Found in established pastures.
Term
The Pesticide Treadmill
Definition
Producers start using more pesticides. Pests are reduced at first but develop a resistance, resulting in increased pesticide use. Repeat.
Term
Photoperiod response.
Definition
A method of classifying vegetable crops. Includes long-day, short-day, and day-neutral responses.
Term
Pinhead square
Definition
The first stage in development of a cotton boll. Susceptible to sap-sucking pests including mites, jassids, thrips, and aphids.
Term
Pioneer upland rice systems
Definition
Rice systems in newly settled areas.
Term
Plastic greenhouse
Definition
Plastic is cheaper than glass. Polyethylene is used, mainly. More insulating, especially when double-layered. Cuts down energy costs 25%. Must be replaced every 3 to 4 years.
Term
Plastic mulch
Definition
A type of protected horticulture. Utilizes natural light. Controls water use efficiency  by preventing evapotranspiration. Plastic sheets laid over the plants outdoors. There are 540,000 ha of plastic mulch worldwide.
Term
Ploidy level
Definition
A way of classifying fruit crops. All temperate fruit cros are diploid except for strawberry, pears, European plum, some blackberries, highbush blueberries, and some apple cultivars. Orchards with triploid cultivars require a minimum of three cultivars per orchard, since the triploid cultivar cannot produce pollen.
Term
Plugs
Definition
A method of transplanting. Reduces transplant shock. Seedlings are grown in a greenhouse in soilless mix in cone shaped containers. Can use peat pots or rockwool (if being transplanted into rockwool).
Term
Plums
Definition
Family Rosaceae. Orginated in North America. There are European, Japanese, and North American plums. There are self-fertile and self-incompatible cultivars. Grown in Hardiness zone 5b, near Lake Ontario. Rootstock is used.
Term
Poaceae
Definition

aka Graminae

aka Grass family

Monocot vegetables. Sweet corn is the ony member.

Term
Polyphageous
Definition
A pest species that feeds on a wide range of hosts. Example: American bollworm.
Term
Pome
Definition
A type of fruit. Saskatoon berries, apples, and pears are pomes.
Term
Pomegranate
Definition
A superfruit.
Term
Pot-in-pot
Definition
A type of nursery. Like container nurseries, but the containers are placed in holes in the ground. ROots are underground, wind cannot tip them over, and larger trees can be marketed. Trees are easier to handle. Root growth is still restricted. Drainage is necessary.
Term
Potted plants
Definition
Sphagnum peat moss is used, which has 75% - 80% pore space, so that water can be held without pooling and drowning roots. Pot size varies from 5 cm to 20 cm in diameter. Many species, including mums, geraniums, poinsettias, lilies, tropical foliage plants, azaleas, kalanchoe, cyclamen, and begonias. Worth $400 million/yer in Ontario.
Term
Precision seeding (pc)
Definition
A method of direct seeding. Seeds are placed exactly where you want a plant to be positioned. Enables high-density planting, and gives a more uniform size of the crop. Seeds must be uniform size and have a round shape. Non-spherical seeds are coated with starchy material to make them round.
Term
Prince Edward County
Definition
A major grape growing area of Ontario. Lake Ontario and the Bay of Quinte features terrior stony soils.
Term
Processing quota
Definition
The amount that a producer is required by contract to produce in a field-grown processing vegetable market system.
Term
Propagation
Definition
A way of classifying vegetable crops. Includes direct seeding, transplants, and vegetative.
Term
Protected containers
Definition
A form of container nursery. Containers are kept in a low-tech greenhouse.
Term
Protected horticulture
Definition
Use of structures to protect plants from/provide temperature, precipitation, air movement, insects, diseases, pests, soil and nutrients, light, CO2, and/or humidity. Includes outdoor plastic mulches, greenhouses, hydroponics, shading, photoperiod control, supplemental lighting, and environmental sensors. Systems classified based on if light is used or not.
Term
Protocrops
Definition
Initial domesticates of crops. Rapid growth, abundant seed production, responds well to fertilier, reduced seed shattering, overcoming of seed dormancy, growth habit, harvest index, gigantism, and resistance to pests and diseases. Evolved into landraces.
Term
Proximity to a body of water
Definition
A factor in choosing a site for fruit production. Fruit production must be close to a lake for climate modifying effects of the lake. Great Lakes are deep and rarely freeze over. Water has high latent heat content and moderates temperature throughout the year. In the spring this delays blossom opening. In the fall this delays frosts and prevents extreme low or high temperatures.
Term
Pruning
Definition
Wastes carbohydrates. Optimizes light penetration. Optimizes vegetative/reproductive growth balance. Controls tree size. Removes unproductive wood (diseased, excessively vigorous). Stimulates branching, reducing apical dominance when the terminal meristem is removed. Trains the tree to have proper spacing and arrangement of branches. Removal of broken, diseased, or infected branches.
Term
Puddling
Definition
Creation of a massive structure-less top soil with a compacted layer underneath. For rice cultivation. Prevents percolation and reduces drainage. Done with a hand tractor or rototiller.
Term
Pumpkin
Definition
A Cucurbitaceae crop. Deep-rooted.
Term
Radish
Definition
A Brassicaeae crop. Direct seeded. A long-day plant. Shallow-rooted.
Term
Rain-fed lowland rice systems
Definition
Non-continuous flooding of fields. Variable dpeth and duration of depth. Direct seeded or transplanted.
Term
Raised troughs
Definition
A popular set-up in greenhouses. Makes greenhouse work more ergonomic.
Term
Raspberries
Definition
A bramble. There are red and black raspberries. A potential greenhouse crop.
Term
Reactive Oxygen Species (ROS)
Definition
A consequence of living in an oxygen atmosphere. They are destroyed by antioxidants.
Term
Red currant
Definition
Ribes rubrum L.
Term
Red raspberry
Definition
Rubus idaeus L.
Term
Redcort apple
Definition
A mutation apple cultivar that arose from Cortland apples.
Term
Redspur apple
Definition
A mutation apple cultivar that arose from Delicious apples.
Term
Redtop grass
Definition
May be foraged by livestock. Found in natural unimproved pastures.
Term
Resistant weeds
Definition
Weeds that developed a resistance to herbicides.Sped up by increased use of herbicides, such as with Roundup Ready cultivars, reduced tillage, and overly simple rotations. In some cases it may be caused by gene transfer from Roundup Ready crops. Resistance is occuring at a rate faster than anticipated. There are no 60 resistant weeds in Canada including wild carrot, giant ragweed, and fleabane. One solution is to rotate herbicides; this is a short-term solution.
Term
Rhizomatous grasses
Definition
Species showing grazing tolerance.
Term
Rhode Island Greening Apple
Definition
A triploid apple cultivar.
Term
Rhubarb
Definition
A perennial vegetable crop. The crown is vegetatively propagated. A long-day plant. Grown for 2 - 3 years in a field, then the roots are moved into a hothouse that excludes light. Shoots are harvested every week for 8 weeks.
Term
Rice blast
Definition

Pyricularia oryzae

A disease that attacks rice. A fungus.

Term
Rice milling
Definition
First the husk is removed, making brown rice, then the hull, making milled rice. Milling recovery can be up to 70%, depending on variety, but usually around 65%.
Term
Rootstock
Definition
Rootstocks are use for apples, pears, plums, apricots, peaches, and cherries. Affects the tree size, soil adaptation, drought tolerance, root anchorage, and cold hardiness. There are dwarfing rootstocks available for apples, pears, and cherries.
Term
Roses
Definition
A cut-flower perennial crop. Grown hydroponically in greenhouses in rockwool. They are a 5 to 6 year crop. Use CO2 and light supplementation.
Term
Rotational grazing
Definition
A type of pasture system. The field is divided into paddocks through which the livestock are rotated systematically. Balances grazing demand and livestock selectivity with growth habits of the plants. Higher yield per are, but higher maintenance requirements.
Term
Roundup Ready
Definition
A transgene first put in soybeans by Calgene. Now owned by Monsanto. Plants are resistant to glyphosate. They contain bacterial EPSPS gene, so they are not affected by glyphosate. This gene could theoretically cause an effect on all the aromatic amino acids produced. Cultivation causes decrease in tillage, since herbicides coul dbe used to clean fields. May cause increased weed resistance to herbide by gene transfer. One solution is to have the gene in non-nuclear DNA (prevents spread of genes through pollen). Monsanto's patent on Roundup Ready expred, so they came out with Genuity Roundup Ready 2 Yield.
Term
Rutabaga
Definition
A Brassicaeae crop.
Term
Saskatoon berry
Definition

Amelncheir alnifolia Nutt.

Family Rosaceae. Originated in North America. A deciduous, 8 meter tall shrub-like tree. Self-fertile. The fruit is a small (5 mm - 15 mm) pome that resembles a blueberry. Harvested June through August. High in riboflavin, biotin, manganese, and antioxidants. 

The city of Saskatoon, SK is named after the berry, not the other way around.

Term
Seed drill
Definition

Before its invention in the 19th century, 75% of planted seeds were lost due to uneven furrow depth and broadcast sowing. Subject of this poem:

 

One for the rook

One for the crow

One to rot

And one to grow

Term
Self-fertile
Definition
A classfication of fruit. Pollen from a different but related cultivar is not required for pollination and fertilization to produce fruit. Just planting one cultivar in a field is possible. All berry crops, apricots, peaches, nectarines, and sour cherries. Some apple cultivars, some sweet cherry cultivars, and some plum cultivars.
Term
Self-incompatible
Definition
A classification of fruit. Pollen from a different but related cultivar is required for pollination and fertilization to produce fruit. More than one cultivar must be planted. Includes pears, some apple cultivars, some sweet cherry cultivars, and some plum cultivars.
Term
Service-oriented horticulture
Definition
Includes golf courses, landscaping, and entertainment farming.
Term
Shallow-rooted crops
Definition
Roots go down 30 cm. Broccoli,