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Plant Breeding: Quiz 1
University of Guelph MBG*4160
181
Agriculture
Undergraduate 4
10/05/2015

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Term
Abscission scar
Definition
A scar which is smooth on wild cereals, and jagged on domestic cereals.
Term
Acala Valley
Definition
A valley in Mexico where upland cotton was grown in the 1960s. Albert E. Percival collected it for breeding programs. In 1984, he returned and found that all the cotton had been removed due to a boll weevil invasion in the 1970s. Now the genes for  this cotton are lost forever.
Term
Accessions
Definition
Samples of germplasms.
Term
Active collection
Definition
A typ of collection in gene banks. Short term storage. Re-planting, regeneration, and evaluation of plant materials.
Term
Adaptation to stressful environments
Definition
A product of plant breeding.
Term
Aegilops squarrosa
Definition
A wild grass species that grows on the shores of the Caspian Sea, northeast of the Fertile Crescent. It crossed with emmer wheat, and produced bread wheat.
Term
Agriculture
Definition
Began 10,500 - 9,500 years ago in southeastern Turkey and northern Syria. The most important historical event since the Ice Age. Triggered a chain of economic, political, and technological developments.
Term
Agriculture and Agri-Food Canada
Definition
Appointed the first plant gene resources officer and established the Plant GEne Resources of Canada (PGRC) in 1970.
Term
Agriculture Research Service (ARS)
Definition
A department of the USDA.
Term
Albert E. Percival
Definition
A plant explorer who collected upland cotton from Acala Valley, Mexico in the 1960s, and returned in 1984 only to find that cotton was no longer grown there.
Term
Alfalfa
Definition
Originated in Turkey, but is a major crop in Canada.
Term
Animal domestication
Definition
Occurred 6,000  years ago.
Term
Annual
Definition
Plants which live for one year. Domesticated plants are often annuals.
Term
Avocados
Definition
Brought from Mexico in 1989, creating an industry in California.
Term
Base collection
Definition
A type of collection in gene banks. Long term storage at low temperature and moisture.
Term
Biodiversity International
Definition
Have an international mandate for conserving plant genetic resources. Collect germplasms for gene banks. Gives highest priority to the ex situ method of germplasm conservation. Developing cryopreservation techniques for tropical tree species such as tea, cacao, and jackfruit.
Term
Blueberries
Definition
A North American crop collected by US and foreign plant explorers. Of economic importance in Canada.
Term
Bob McIntosh
Definition
Found out what genes had been introgressed into wheat from GP2 and GP3 populations.
Term
Bread wheat
Definition
Produced from a cross between Aegilops squarrosa and emmer wheat. The single most valuable crop in the modern world.
Term
Breeding
Definition
The art of genetic modification of a species in order to produce a population or variety with the desired phenotype. Efficiency is dependent on successful utilization of genetic variation in plant populations. Reduces genetic variation.
Term
Breeding line
Definition
A type of cultivated plant stored in gene bank collections. Material obtained by plant breeders as intermediate products in pre-breeding. Have a narrow genetic base; often originate from a small number of parents.
Term
Calvin R. Sperling
Definition
An ARS plant explorer who went to Turkey in 1989 to look for PI 178383, or other disease-resistant wheat varieties. Found that actually it originated in northern Iraq.
Term
Canada Committee on Crops (CCC)
Definition

aka Expert Committee on Plant Microbial Genetic Resources

Reports to the Canadian Agriculture Research Counsel. Gives advice on plant and genetic resource policies and activities. Draws representation from Canadian federal and provicial government agencies, universitiesk industry, scientific societies, and non-government organizations. Discusses and advises on activities of the national program in plant genetic resources, makes recommendations on issues relating to plant and microbial genetic resources, and participats in the formulation of national plant and microbial genetic resource policy and its relationship to international programs. 

Term
Canadian Clonal Genebank
Definition
Designated in 1989 as the primary germplasm respository for fruit trees and small fruit crops. Orignally it was near Trenton, but it moved to Harrow, Ontario in 1996. The primary contact point for national and international contacts, distribution, rejuvenation, seed viability testing, database management, technical information, and evaluation of germplasm not assined to any node. Has about 3,000 accessions. Two thirds are wild relatives of Canadain fruit crops, the other third are cultivars or breeding selections of Canadian origin fruit crops of interest to Canadian scientists. Seeds are stored in the field, in greenhouses, in vaults, and with cryopreservation tecnhiques.
Term
Canola
Definition
An example of Canada's contribution to enriching the world's crop diversity as a result of germplasms acquired in other countries.
Term
Central America
Definition
A Centre of Origin. COrn, beans, squash, peppers, and upland cotton were domesticated here.
Term
Central Asia
Definition
A Centre of Origin. Wheat, peas, lentils, beans, cotton, flax, safflower, and hemp were domesticated here.
Term
Centre of diversity
Definition
A modification of the Centre of Origin theory. Includes primary and secondary centres of diversity.
Term
Centre of Origin
Definition

aka Primary Centre of Diversity

A geographic range where domestication of a specific crop began. In these areas the genetic diversity of the crop is very high (but may not be the highest). Wild ancestors of the crop are found here, and many landraces. Many dominant alleles for wild traits are found here. Centres of Origin have mountains, are close to the equator, and have great climatic variation. Include: China, Southeast Asia, Central Asia, Near East, Mediterranean, Ethiopia, Central America, and South America.

Term
Cereal Research Centre
Definition
Part of the multi-nodal system. A station in Winnepeg responsible for cereals including wheat, oats, and barley.
Term
China
Definition
A centre of origin. Buckwheat, soybeans, millet, peas, apples, and plums were domesticated here.
Term
Chromosome substitution line
Definition
Lines where one chromosome is different from the rest of the species.
Term
Commercial varieties
Definition
A type of cultivated plant stored in gene banks. Standardized commercial varieties which were obtained by professional plant breeders. High productivity when subjected to intensive management practices. Includes obsolete varieties. Used in the breeding of new varieties, but limited due to uniformity. Number of varieties is increasing rapidly.
Term
Consultative Group of International Agricultural Research (CGIAR)
Definition
Has regional and crop mandates. Collect germplasms for gene banks.
Term
Convention on Biological Diversity
Definition
Gives highest priority to the in situ method of germplasm conservation.
Term
Corn
Definition
Domesticated from teosinte in Mexico and Guatemala, but is a major crop in Canada.
Term
Corn yields
Definition
Increased by six times between 1930 and 1980. Increased planting density in this time. Corn plants are now much more adapted to growing in high densities.
Term
Cranberries
Definition
A North American crop collected by US and foreign plant explorers. Of economic importance in Canada.
Term
Cryopreservation
Definition
A method of conservation of germplasm. Plant tissues are stored at very low temperatures in or over liquid nitrogen for long-term storage. At the PGRC, seeds are kept at -196ºC. This is the most highly developed technique of germplasm conservation. Seeds can last up to 100s of years.
Term
Cultivated plants
Definition
Found in gene banks. Includes some commercial varieites, landraces, breeding lines, and specific genetic stocks.
Term
Cultural improvements
Definition
One of the components of yield increase. Fertilizers, planting density, et cetera...
Term
Currants
Definition
Of economic importance in Canada.
Term
Dandelions
Definition
Can be used to make rubber. Avoids the economic problems of using the rubber tree. A special type of dandelion from Kazakhstan is used. They are breeding it into a new Ontario crop: a pure domestication. Dandelions are a wild species that germinates thatches of grass; they will not germinate on bare soil. The puffball is not conducive to cultivation.
Term
David Fairchild
Definition
The first chief of the USDA plant collection program. Appointed chief in 1898. His plant explorers brought germplsm to the US which profoundly affected agriculture by improving existing industries and creating new industries. Invented the plant inventory system, and introduced black dates, pima cotton, pistachios, gooseberries, olives, walnuts, and many other crops.
Term
Day-length
Definition
As you move north, summer day-length increases. Photoperiod sensitive crops do not flower if moved outside of their day-length zones; humans had to select for new types as they migrated north or south.
Term
Dioecious
Definition
Having separate male and female plants. During bad pollination years, reproduction is low.
Term
Direct use
Definition
A type of wild plant found in germplasm collections. Species that are not cultivated by can be used in breeding programs. Have genetic erosion by selection.
Term
Disease resistance
Definition
A product of plant breeding.
Term
Domestic cereals
Definition
Mutants of wild cereals that do not shatter, but separate when threshed. The abscission scar is jagged. The earliest indehiscent domestic wheat was dated to around 9250 years ago, but it is estimated that domestication happened less than 200 years before this. With incrased indehiscence, terminal spikelets became more common. Younger archaeological sites had more domestic cereal spikelets. Size of the grain depends on position in teh ear and environmental conditions. It took thousands of years of slow changes in different places for wheat to domesticate.
Term
Domestic plants
Definition
A plant is domesticated if it cannot survive in the wild. Characteristics of domestic plants include: larger plant, larger seed, rapid germination, uniform germination, unusual colours, loss of defensive structures, loss of poisonous substances, simultaneous ripening, self-pollination, annual habit, and less branching of root crops.
Term
Domestication
Definition
A result of genetic diversity and artificial selection. First a species is selected. Second, there is selection of tame types in a species. Lastly, cultivated habitats set the stage for domestication. Harvesting seeds from wild plants subsamples plants with larger seeds (don't fall through your hand), tall plants (easier to reach), and plants which mature at the time of harvest. This sub-sambling decreases genetic diversity.
Term
Durum wheat
Definition
Was brought to the US by Mark A. Carleton in 1898. Has drought tolerance. Tastes better in pasta.
Term
Einkorn wheat
Definition

Triticum boeotium Boiss.

Wild wheat grown in Turkey. Its wild ancestor is very similar to cultivated varieties, and still grows in the Fertile Crescent. Heun et al pinpointed the origin of domestic einkorn to the Karacadag mountains in southeast Turkey. Its domestication was relatively quick and easy; changes were only: heavier, denser seeds (more productive), and a firm stalk (makes seed more easily harvestable).

Term
Embryo rescue technique
Definition
A technique for making crosses with G2 or G3 individuals. The embryo is removed very early on and grown in tissue culture. Sometimes it is needed to cross it back with one of the parents for several generations to make a stable plant.
Term
Emmer wheat
Definition

Triticum dicoccoides

Wild wheat grown in Turkey.

Term
Ethiopia
Definition

aka Abyssinia

A centre of origin. Wheat and barley were domesticated hhere. Also a secondary centre of diversity for wheat.

Term
Evolution
Definition
A result of genetic diversity combined with natural selection.
Term
Ex situ
Definition
A method of conservation of germplasm. Takes place far away from the plant's natural habitat. Important for gene pools. Began on a wide scale 30 years ago, now practiced in almost all countries. Gene banks with accessions collected through exchange. Techniques allow seeds of many species to be conserved up to 100s of years, by drying seed and storing it at low temperatures. Biodiversity International gives highest priority to this method for its practicality and wide application.
Term
Fertile Crescent
Definition
A broad area in northern Iran and Iraq. Domestication first began here. Wheat, barley, lentils, peas, vetch, chickpeaks, and flax were domesticated here.
Term
First cross made between plants
Definition
Made in 1760. A cross of tobacco plants, trying to modify the length of the flower tube. The first suggestion of quantitative inheritance.
Term
Frank N. Meyer
Definition
The dean of the USDAs agricultural explorers from 1905 1918. Introduced thousands of plants including: alfalfa sprouts, zoysia grass, apples, barley, chestnuts, bean sprouts, Chinese celery, cabbage, Meyer lemon, Bradford pears, dwarf lilacs, Amur cherry, gingko trees, rose rootstocks, Siberian and Chinese elms, and soybeans.
Term
Forage grasses
Definition
A North American crop collected by US and foreign plant explorers. Of economic importance in Canada. Includes bluegrass, milk vetch, and wild rye.
Term
Fredericton Research Station
Definition
Part of the multi-nodal system. A station in Fredericton responsible for potatoes. Uses tissue culture methods of preservation.
Term
Gathering
Definition
The gathering of cereals began 19,000 years ago in the Near East.
Term
Gene banks
Definition
Plant germplasm collections. Sources of genetic variation. A collection of seeds and other plant reproductive material, primarily cultivated plants and their wild relatives. Secure conservation of these plants, and provide access to them. There are 1308 gene banks around the world, collected by institutions such as Biodiversity International. Ensures that varieties are secure and held in more than one place. Helps with crop improvement, prevents over-reliance on too narrow of a genetic base. Mitigates effects of genetic erosion as traditional crops are replaced with commercial vareities, and there is deforestation, desertification, and habitats are destryed. Germplasm is stored in situ, ex situ, in vitro, or using cryopreservation. Includes base, active, institutional, and national duplicate collections.
Term
Genetic diversity
Definition
Necessary for crop development. Plant breeders need genetic diversity to find useful traits in different plants and combine them through hybridization and selection. Specific traits might be found in: local germplasms, germplasms from other regions, landraces from a centre of diversity, or wild species.
Term
Genetic drift
Definition
Genetics changing randomly simply due to sub-samping without selection. Not a form of evolution.
Term
Genetic improvements
Definition
One of the components of yield increase. Accounts for 50% - 70% of increase.
Term
Genetic Resource Information Network (GRIN)
Definition
A national program for germplasm collection. A department of the USDA. A computerized database management system for handling massive amounts of data associated with genetic resources. Data is in three categories: passport, evaluation, and stock management. Scientists can learn about characteristics of each accession in the collection. All nodes in the multi-nodal system interact with the database regularly, entering data, conducting searches, and making seed requests. Provides information on season, winter hardiness, resistance to pests, diseases, environmental stresses, quality factors, and other traits in accessions.
Term
Geneva SAES
Definition
Keeps cool-season grapes, tomatoes, apples, and some minor crops.
Term
Germplasm
Definition
Material basis of heredity. The potential hereditary genetic stock within a species, purpose of plant breeding, preservation, and other research uses.
Term
Ginseng
Definition
Found in the understory of shady forests. Not a fully domesticated crop. It has shade requirements and is grown under shade-cloth. Accumulate root diseases in the soil. Requires a stratification process before germination can take place.
Term
Grapes
Definition
A North American crop collected by US and foreign plant explorers.
Term
Green Revolution
Definition
In the 1960s there was a huge jump in yield.
Term
Guelph Millennium Asparagus
Definition
An OAC asparagus hybrid created by Dr. Woyln. The most popular asparagus in Ontario.
Term
Hard red wheat
Definition
Was brought to the US by Mark A. Carleton in 1898. Has drought tolerance. Makes better tasting and more nutritious bread.
Term
Harlan de Wet
Definition
In 1971, proposed that plants be grouped into three gene pools based on feasibility of transfer: primary, secondary, and tertiary gene pools.
Term
Heun et al
Definition
Analyzed the DNA from 68 lines of cultivated einkorn, and 2651 lines of wild einkorn from the fertile crescent, and used genetic markers to pinpoint the origin of einkorn to the Karadag mountains in southeast Turkey. This discovery lead to pinpointing the origins of many other crops in Turkey.
Term
Humans
Definition
Evolved around 50,000 years ago. The first humans hunted animals, gathered seeds, fruits, and nuts. There were no domestic plants.
Term
Improved varieties
Definition
Do best in high-input systems. Don't do as well as traditional varieties in traditional, low-input system.
Term
In situ
Definition
A method of conservation of germplasm. Protects plant genetic resources in their natural habitats. The Convention on Biological Diversity gives highest priority to this method. Includes wild species, landraces, and other cultivated forms. Complemented by ex situ conservation.
Term
In vitro
Definition
A method of conservation of germplasm. Stores germplasm as plant tissues. Widely regarded as an important alternative field gene banks for conservation of recalcitrant seeds, and vegetatively propagated plants.
Term
Increased quality
Definition
A product of plant breeding. Increased vitamin A in carrots and squash. Increased sugar in sugar beets and sweet corn. Increased monosaturated oils in sunflower seeds.
Term
Indehescence
Definition
A selection pressure for domestic cereals, but it was not a very strong selection pressure at first because farmers harvested spikelets before they shattered, and if there was a crop failure, farmers would gather cereals from the wild.
Term
Indirect use
Definition
A type of wild plant found in germplasm collection. Wild species related to cultivated species by possessing beneficial traits that can be transferred to cultivated species. Transfer by sexual crosses, somatic hybridization, or genetic engineering.
Term
Insect resistance
Definition
A product of plant breeding.
Term
Institutional collection
Definition
A type of collection in gene banks.
Term
International Rice Research Institute (IRRI)
Definition
In the Philippines. They keep a secure backup of rice germplasm in the NSSL, due to concern that a typhoon might  destroy their own collection, which includes 80,000 accessions of rice. They are research into low-input, low-cost, low-tech methods of germplasm conservation, such as sun drying, chemical desiccants, ventilatioin, storage without refrigeration, and ultra-dry moistuer contents.
Term
Introgression
Definition
Genes from one species found in the genome of another species as a result of a cross a long time ago. Happens naturally.
Term
Irish potato famine
Definition
The potato, the staple food of Ireland, was destroyed by blight, resulting in the starvation of millions of people. This might have been avoided if Irish farmers had had more diversity in crops. An example of the importance of germplasm collection and a large genetic base.
Term
Jack R. Harlan and Osman Tosun
Definition
Collected PI 178383 from Turkey in 1948.
Term
Karacadag mountains
Definition
The origin of domestic einkorn. In southeastern Turkey. The origin was pinpointed by Heun et al. Nearby archaeological sites contain remnants of wild and cultivated einkorn; some of the oldest farming sites in the Fertile Crescent.
Term
Kroelreuter
Definition
First synthesized artificial hybrids in 1760, and found that they were intermediates of their parents.
Term
Landrace
Definition

aka Traditional variety

A type of cultivated plant stored in gene banks. A domestic population endemic to one area with origins dating back 100s of years. A mixture of types, influenced by migration and natural and artificial selection. Occurs in situations where farmers do not exchange seeds, and save seed year after year. Without formal bland breeding the crops diverge and become well adapted to the local environment (soil, climate, pest), and the farmer's personal preferences. Abundant source of potentially useful genetic variation, but they are disappearing rapidly. Not adequately represented in most gene bank collections.

Term
Lattice
Definition
A commonly used experimental design. An extension of RCBD, where large blocks are subdivided into smaller, more homogenous incomplete blocks.
Term
Law of Homologous Series of Variation
Definition
Species that are closed related undergo similar changes in the process of domestication. Example: different small grains would both acquire non-shattering. If one type of crop is domesticated, it is often not necessary for humans to domesticate another.
Term
Long-term storage
Definition
A type of storage at the PGRC. A large walk-in vault where seeds are kept in laminated envelops at -20ºC. Seeds are first evaluated for viability, then dried to 6% - 8% moisture.
Term
Mark A. Carelton
Definition
A USDA plant explorer. Brought durum wheat and hard red wheat to the US in 1898. Raised wheat yields from 60,000 bu/year to 20 million.
Term
Mediterranean
Definition
A centre of origin. Flax, barley, and beans were domesticated here.
Term
Medium-term storage
Definition
A type of storage at the PGRC. A large walk-in vault where seeds are kept in paper envelops at 4ºC and 20% relative humidity. Seeds are first evaluated for viability, then dried to 6% - 8% moisture content.
Term
Meyer lemon
Definition
A variety brought to the US by Frank N. Meyer. Important source of frozen lemon juice, grown commercially in Texas, South Africa, and New Zealand.
Term
Migration
Definition
Humans moved crops out of their domestication centres. Oats and rye were brought to northern Europe by accident (they were weeds), but became an important crop because they have higher tolerance for cold.
Term
Molecular marker
Definition
A DNA sequence for different alleles. The "finger printing" of crops.
Term
Multi-nodal system
Definition
Established in 1992 to respond to recommendations from study committees on the enhancement of germplasm conservation in Canada. Initially funded by Green Plan. Links rejuvenation, evaluation, and documentation to research and plant breeding programs for specific crop plants. Strategy is consistent with recommendations for Food and Agriculture Organization of the United Nations; shares germplasm with all nations. Offers opportunities for Canadian germplasm conservation, so that the institute can concentrate on preservation technologies, genetic diversity analysis, distribution, database development, rejuvenation, and evaluation of species. Includes the Cereal, Fredericton, and Saskatoon Research Centres.
Term
National duplicate collection
Definition
A type of collection in gene banks.
Term
National Germplasm Resources
Definition
Part of the ARS. Oversees plant exploration.
Term
National Seed Storage Laboratory (NSSL)
Definition
In Fort Collins, Colorado. Keeps long-term storage of the entire germplasm collection; a back-up for the other collections. The "Fort Knox of plants". One of the most advanced plant and seed storage facilities in the world. Many countries and research centres keep some accessions from their more valuable collections here.
Term
Near East
Definition
A centre of origin. Wheat (9 species), rye, alfalfa, Persian clover, vetch, grapes, peas, cherries, and pomegranate were domesticated here.
Term
Near isogenic lines
Definition
Lines where one parent has a trait and the other doesn't.
Term
New species
Definition
A product of plant breeding. Example: triticale, some ornamentals.
Term
New World
Definition
Has a north/south layout, so domestic species had to adapt to new day-lengths and climates as they spread; this slowed down the spread of agriculture. Spread was so slow that some species were domesticated separately in relatively close regions. Example: squash, cotton.
Term
OAC Rex
Definition
A successful variety of common bean with common bacterial blight (CBB) resistance. Has genes from both P. vulgaris and P. accut. Had to use hybrid embryo rescue technique to produce this cross, and crossed it back with P. vulgaris.
Term
Old World
Definition
Emmer wheat was domesticated very quickly in Turkey, where many other useful species were also living. This lead to humans domesticating a balanced package of species that met all our needs: carbohydrates, protein, oil, milk, animal transportation and traction, and vegetable and animal fibres. The west/east layout of the Old World allowed for quick spread of domestic species: crops did not have to adapt to new day-lengths, climates, and diseases. Spread was so fast that it reached Pakistan and the Balkans in only 2,000 years. Agricultural culture out-competed hunting-gathering. This culture allowed for professions other than food-procurers, such as bureaucrats, scribes, soldiers, metal-workers, and other types of craftspeople. Humans then developed literacy, metallurgy, stratified societies, and advanced weapons. Defense sedentary populations lead to crowd epidemic diseases such as smallpox.
Term
Onions
Definition
Photolength sensitive. There are short day and long day onions. Cannot migrate north or south easily.
Term
Paraguay
Definition
The ARS provides training in germplasm utilization to Paraguayan scientists, and gives them open access to germplasm banks, in return for use of pepper germplasm from Paraguay.
Term
Peach rootstock
Definition
In the US they are grown from descendants from germplasm collected in the 1920s.
Term
Pecans
Definition
A North American crop collected by US and foreign plant explorers.
Term
Perennial
Definition
A plant that lives for many years. Some perennials do not flower in their first year, or even first few years.
Term
PI 1
Definition
The first accession entry into the plant inventory system. A cabbage from Moscow, Russia, collected in 1898. It matures a little earlier than Jersey Wakefield, but forms a head too small for market.
Term
PI 178383
Definition
A variety of wheat collected from Fakiyan Semdinli, Turkey in 1948 by Jack R. Harlan and Osman Tosun. It has lodging, no winter hardiness, and is susceptible to leaf rusts. However, it has resistance to 4 races of stripe rust, 35 races of common bunt, 10 races of dwarf blunt, and tolerance to flax smut and snow mould. Appears in the pedigree of virtually all wheat grown on the Pacific Northwest. Calvin R. Sperling came back to Turkey to look for more of it in 1989, but found that it actually originated in northern Iraq, and was taken to Turkey a few years before it was discovered by Harlan and Tosun. Political instability now makes it impossible to collect more PI 178383, and it may be all gone.
Term
PI 600000
Definition
A pollinator sunflower with a shorter than normal height. Promotes high yields in hybrids. Developed by the ARS breeding program.
Term
Plant breeding
Definition
Arose as a discipline in 1727 with Mendel's experiments, and Vilmorin Seed Company. By the late 1800s there were variety crosses, mass selection, pedigree breeding, and field trials. The concentration of sugar in sugar beets was doubled by selection. By the 1900s, empirical knowledge on selection was abundant.
Term
Plant density
Definition
A contributor to corn yield increase in the US in the last 80 years. In 1930 density was 30,000 plants/ha. In 1980 it was 64,000 plants/ha. Plants were bread to be more tolerant of high planting densities.
Term
Plant domestication
Definition
Crops were domesticated from wild, weedy species. Most crops were domesticated by 1000 BC. Only 3,000 plant species out of 250,000 are domesticated. 150 crops are cultivated extensively, and 10 account for 90% of calories consumed by humans.
Term
Plant exploration
Definition
Collecting germplasm of crops from all over the world. Crops must be continuously enhanced to overcome diseases, pests, drought and temperature tolerance, new growing conditions, and creating more productive, nutritious, durable, or better tasting varieties. Collectors provide the genetic mateiral for breeding improved varieties. No one country or one continent has neough genetic resources to sustain crops at the level which is needed.
Term
Plant Gene Resources of Canada (PGRC)
Definition
A national program for germplasm collection, appointed by Agriculture and Agri-Food Canada. It was located in Ottawa, but in 1998 it was moved to Saskatoon. Participates in a worldwide network of plant genetic resources established by the Food and Agriculture Organization of the UN and the International Plant Genetic Resources Institute. On Canada's behalf, it accepted responsibility for world base collection of barley and oats, and duplicate collections of pearl millet, oilseeds, and green manure crucifers. Includes long-term, medium-term, and cryopreservation storage.
Term
Plant introduction
Definition
Seeds or vegetative propagules that have been introduced from another region. Collecting plants from other countries is an important method of obtaining plant introductions. Maintained and stored at gene banks. All countries rely on plant introductions to maintain production and consmption levels in plant breeding.
Term
Plant introduction number
Definition
A number given to accessions in a plant inventory system. Begins with PI, then a designated number. Numbers are only given after evaluation that the accession is a new germplasm.
Term
Plant inventory system
Definition
Invented by David Fairchild. Every accession that enters a germplasm system (collected by plant breeder or result of a breeding program), is given a plant introduction number.
Term
Potato
Definition
A very diverse crop. Has many different traits in colour, shape, size, starch composition, flavour, and plant characteristics.
Term
Potentially usable
Definition
A type of wild plant found in germplasm collections. Not used, but might have traits or genes which could be useful in the future.
Term
Pre-breeding
Definition
Activities designed to identify and evaluate desirable characteristics and/or genes from unadapted materials that cannot be used directly in breeding programs. Transferring these traits into an intermediate set of materials that breeders can use further in producing new vareities for farmers. A necessary first stop in use of genetic diversity, arising from wild relatives or unimproved materials, to create pre-breeding populations. Takes 5 - 8 years.
Term
Primary gene pool (GP1)
Definition
Includes the cultivated species and related species from which genes are most readily obtained. Normal F1 and F2 progeny are produced, and the segregation of genes is predominantly normal. The most important gene pool.
Term
Queen Anne's lace
Definition
A weed which is the same species as carrots. Dr. Wolyn foudn male-sterile mutants in a field in Guelph, where there is now a housing complex.
Term
Rachis
Definition
The mechanism on cereal plants that breaks off, dispersing seeds. On domestic species, the rachis is rough, and the seeds are not shed at maturity. This maximizes yields.
Term
Randomized complete block design (RCBD)
Definition
A commonly used experimental design. Entries are randomized within a block. Ideally, variation among blocks is maximized, and variation within blocks is minimized.
Term
Raspberries
Definition
Of economic importance in Canada.
Term
Recalcitrant seed
Definition

Seeds unable to withstand drying, and/or cannot be stored at low temperatures. The lifespan is limited to a few weeks or months. Example: coconuts, cacao.

Coffee, citrus, and oil palm seeds can be dried, but cannot be stored at low temperatures. These seeds are often stored in vitro, and are expensive to maintain.

Term
Regional Plant Introduction Stations
Definition
There are four in the US, one for each SAES. New accessions are sent here. Created in 1948 by USDA and SAES to maintain the collections of different crops.
Term
Rice
Definition
Brought from Japan in 1900, creating an industry in Louisiana and Texas.
Term
Saskatoon berries
Definition
Of economic importance in Canada.
Term
Saskatoon Research Centre
Definition
Part of the multi-nodal system. A station in Saskatoon responsible for crucifers and forage crop germplasms (legumes and grasses).
Term
Scientific names
Definition
Provide a means of understanding the taxonomic relationship among plnats. A helpful starting point for selecting species from which useful genes can be extracted.
Term
Seaton A. Knapp
Definition
A USDA plant explorer whho brought back rice from Japan, opening up the rice industry in Louisiana and Texas. US started exporting rice rather than importing it.
Term
Secondary Centre of Diversity
Definition
A geographical area where a crop was introduced, and there it evolved and adapted to the new environment. It can have different ecology (insects, diseases), and climate conditions (elevation, temperature, humidity), and day-length than the centre of origin. New diversity arises by natural selection, artificial selection, and by mutations. There can be more diversity among landraces than that which is observed at the true centre of origin, especially if the environment is diverse. Many recessive alleles for domestic traits are found here. No wild ancestors of the crop are found here.
Term
Secondary gene pool (GP2)
Definition
Includes species from which genes can be transferred into the cultivated species with some difficulty. Hybrid seeds can be obtained, but F1 plants are weak, difficult to maintain, or have chromosomes pairing that may be poor or not occur. Progeny may be sterile, the segregation of genes abnormal. Recovery of desired genes can be difficult. Only considered if the desired trait is not found in the primary gene pool.
Term
Seedless fruit
Definition
A product of plant breeding. Bananas, limes, oranges.
Term
Self-pollination
Definition
Domestic plants are often self-pollinated so that even during bad pollination conditions, there is high yield.
Term
Siberian and Chinese elms
Definition
One of the most important plants brought to the US by Frank N. Meyer. Used in the drought in the 1930s, in the 17,000 miles of shelterbelts that were created to reduce wind erosion in the "dust bowl" prairies, helping conserve millions of tons of soil.
Term
Somalia
Definition
During a conflict, all the crops were destroyed and the national germplasm collection was lost. Luckily, a duplicate set of 300 accessions of sorghum and corn had been carried to Kenya by a Biodiversity International collector in 1989. There were also some accessions in India, Nigeria, Russia, and the US. They were returned to Somalia. This is an example of the importance of germplasm conservation.
Term
South America
Definition
A centre of origin. Corn, tomatoes, lima beans, peanuts, pineapple, and cassava were domesticated here.
Term
Southeast Asia
Definition
A centre of origin. Rice, sugarcane, cotton, jute, sesame, and ginger were domesticated here.
Term
Soybean
Definition
Introduced to the US by Frank N. Meyer. He brought back 8 varieties from China in 1905. They were grown for animal forage. Between 1904 and 1908 he added 42 new varieties, including the one that began the soybean oil industry, worth millions of dollars today. He suggested that the US start producing tofu, but this did not catch on until years later. A major crop in Canada.
Term
Specigic genetic stock
Definition
A type of cultivated plant stored in germplasm collections. Genetic combinations, natural or artificially produced mutants, plants with genetic marker genes, monosomic and trisomic individuals.
Term
Spinach
Definition
A variety collected in Manchuria in 1900 saved the Virginia spinach industry from a blight disaster in 1920.
Term
State Agriculture Experiment Stations (SAES)
Definition
Stations managed by ARS. There are four SAES: Ames, Iowa; Geneva, New York; Griffin, Georgia; and Pullman. Each one has a regional plant introduction station. Sites were chosen to represent main agricultural environments of the US.
Term
Strawberry
Definition
Modern strawberries were synthesized by an interspecific hybridization: F virginiana x F. chiloensis. A North American crop collected by US and foreign plant explorers. Has multiple ploidy levels. Of economic importance in Canada.
Term
Sunflower
Definition
Originated in Colorado. The only one of the 20 major crops in North America which originated in North America. Among the top 4 oilseeds in the world. Russian researchers used US sunflowers to breed varieties that started the sunflower oil industry. Of economic importance in Canada.
Term
Teosinte
Definition
The wild ancestor of corn.
Term
Tepary beans
Definition
A North American crop collected by US and foreing plant explorers.
Term
Tertiary gene pool (GP3)
Definition
Gene transfer from these species into the cultivated species requires special techniques, and may not be possible. Some crosses can be made using embryo culture to obtain a viable hybrid plant. Grafting, tissue culture, or chromosome doubling may be required to obtain fertility in the hybrid. Only used in exceptional situations.
Term
Timopheev's wheat
Definition
A wheat species that was domesticated due to the spread of einkorn and emmer wheats in the Old World.
Term
Tissue culture
Definition
An advanced method of germplasm conservation used for many species. A cloning method -a whole plant is grown from a plant part in artificial medium, in a controlled, disease-free environment. used at the Fredericton Research Centre.
Term
Totipotency
Definition
When every cell has the ability to regenerate into a full plant.
Term
Turkey
Definition
The centre of origin for many crops, including einkorn, chickpea, butter vetch, grapes, olives, barley, emmer wheat, peas, lentils, and flax, as well as livestock, sheep, pigs, goats, cattle.
Term
Urban civilizations
Definition
Established 6,000 years ago in Mesopotamia. Less time was spent making food, freeing up time for other professions. Dense populations lead to resistance to crowd epidemic diseases.
Term
USDA
Definition
Have plant explorers, but always ask host countries for permission before exploring, and share findings with them.
Term
Varro
Definition
A Roman Scholar. In 100 BC, recommended collecting the largest seeds from the best looking spikes of wheat.
Term
Vavilov
Definition
A Russian scientist who, in the 1920s, studied genetic diversity of plants. Discovered centres of origin.
Term
Village farming
Definition
Established 7,000 years ago in the bottomlands of the Near East.
Term
Vilmorin Seed Company
Definition
The first seed company. Established in Europe in 1727.
Term
Virgil
Definition
A Roman poet. In 70 - 19 BC, stated that crops degenerate without selecting seed by hand year after year.
Term
Virginia spinach
Definition
In 1920, wilt and blight became very virulent. The genes for resistance were foudn in samples that had been collected 20 years earlier in Manchuria by a USDA plant explorer. These genes are not in almost every disease-resistant spinach variety.
Term
Von Seghaske
Definition
Tried to domesticate lupins for a forage crop. Had defined objectives: increase seed size (handles better), eliminate alkaloids (makes it less bitter, 1 in 2 million plants), eliminate pod cracking/loss/dropping seeds (1 in 10 million), develop hard seed coat, eliminate hairs on seeds (makes seeds stick together), eliminate soil water and pH sensitivity, and non-branching (too tangly, hard to harvest). All these traits were recessive alleles.
Term
Wheat
Definition
Has a long history of breeding. Originated in the Near East, but is a major crop in Canada.
Term
Wild cereals
Definition
Seeds shatter at maturity, there is a smooth abscission scar. Terminal spikelets fall off first, so are less common than base spikelets. Older archaeological sites had more wild cereal spikelets. Cultivated for over 1000 years before emergence of domestic cereals.
Term
Wild oats
Definition
A vareitey found in Israel in the 1960s had genes that helped breeders develop one of the world's most disease-resistant oat varieties.
Term
Wild plants
Definition
Self-perpetuate; seeds are shed. They are highly variable, great genetic diversity. Staggered germination and staggered maturation avoid early frosts. They are many alleles. Foun in germplasm collections. Includes direct use, indirect use, and potentially usable plants.
Term
Wilson Popenoe
Definition
A USDA plant explorer who brought back avocados, oranges, and other trpical fruit varieties from South and Central America.
Term
Yield increases
Definition
Due to a combination of genetic improvements and cultural improvements. The largest increase in yields has been in the last century. Improved varieties are often released simultaneously with cultural improvements; they are bred to do well in high-input systems.
Term
Zoysia grass
Definition
Brought to the US by Frank N. Meyer, but did not evolve into a commercial variety until 1951.
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