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Details

FRSC 331
Vineyard Irrigation
43
Agriculture
Undergraduate 3
10/22/2012

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Cards

Term
Percent of water in plant parts
Definition
-90% of leaves and berries
-50% of woody tissue
Term
Role of water in plants
Definition
-solvent: osmosis
-reactant in photosynthesis
-manitains turgidity of plant cells (opening and closing of stomata)
Term
Water delivery methods
Definition
-Drip irrigation
-Sprinkler: mostly for cover crop establishment and frost control
-Furrow/Flood
Term
Water and soils
Definition
-soil is the reservoir for water in vineyards
-water is held as a film around soil particles and pores
Term
Saturated
Definition
when all of the pores are filled and the air is displaced
Term
waterlogged
Definition
when more water is added to saturated soils
Term
how to reach field capacity?
Definition
let the saturated soil drain under the influence of gravity
Term
Wilting point
Definition
no water is available to plants
Term
As soil approaches Permanent Wilting Point (PWP) what happens to vine?
Definition
vine performance and vigor declines rapidly
Term
What are units for tension?
Definition
pascals or megapascals
Term
As soils dry why is it difficult for a plant to absorb that water
Definition
because the water is held at a greater tension by the soil
Term
When does water stress symptoms and loss of yield occur?
Definition
when more than 50% of available water has been extracted
Term
Transient wilting
Definition
when plants wilt during day, but recover at night
Term
Permanent Wilting Point (PWP)
Definition
when plants wilt during the day but fail to recover at night
Term
how to you find the available water?
Definition
FC (Field Capacity) - PWP = available water.
-expressed in in/foot or mm/meter
Term
Factors that influence irrigation
Definition
-soil texture
-soil depth
-rootstock
-floor management
-climate
-stage of development
-size of canopy
-use of crop
Term
Soil texture influence on water
Definition
-sandy soils: water spreads vertically
-clays: water spreads laterally
-sand: need emitters close together, want to overlap watering
Term
floor management influence on water
Definition
-cover crops can compete with vines for water
-well managed can increase soil water retention and water infiltration
Term
soil depth influence on water
Definition
a deeper soil or finer texture can store more water
-clay or silt loam: 2.5 in H20/ft of soil
-sand or gravel: 0.8 in/ft
Term
rootstock influence on water
Definition
rootstocks vary in drought tolerance, due to rooting depth and number of branch roots
Term
canopy size influence on water
Definition
-transpiration directly related to surface area.
-larger canopies use more water
Term
Use of crop (table, raisin, wine) influence on water
Definition
-not subjected to regulated deficit irrigation (RDI)
Term
water moves from soil to roots b/c of osmotic potential, which is?
Definition
when solute concentration of root is higher than solute concentration of soil
Term
water then travels....
Definition
through root cells into xylem tissue
-pulled up through xylem b/c of transpiration through leaves
Term
what are root hairs?
Definition
single cells that lack cuticle, provide a high curface area
Term
indirect irrigation applications
Definition
-leaching: salts can be leached from the root zone
-frost protection
-fertigation
-heat supression
-cover crop establishment
Term
what happens to water in fruit?
Definition
-either stored there and becomes the solvent for sugar and other compounds
Term
what happens to water in leaves?
Definition
-it will diffuse across cell walls into cells or be lost through stomata to atmosphere
Term
what is the evaporation-tension-cohesion mechanism
Definition
when water that is lost through the stomata lowers pressure, maintains a pressure gradient from roots to leaves
Term
what two ways is water lost to the atmosphere?
Definition
1.) Evaporation (Es: evaporation through soil)
2.) Transpiration (Ef: evaporation through foliage)
Term
Evapotranspiration
Definition
ET= Es + Ef
Term
Rate of evaporation depends on
Definition
-frequency of wetting the soil
-area of soil surface wetted
-proportion of soil surface thats shaded
-air temp
-humidity (vapor pressure gradient)
-wind speed at ground level
Term
effects of transpiration
Definition
-cool leaves
-basis for the evaporation-tension-cohesion continuum
-increases the absorption of minerals
Term
how much of the water absorbed by the plant is used
Definition
-95% lost by transpiration
-5% or less used for metabolism and growth
Term
Transpiration process
Definition
1.)Vapor pressure gradient (transpiration depends on ambient humidity)
2.)Temperature
3.)Wind: removes boundary layer of leaf and stomates close
Term
Types of irrigation systems
Definition
-pressurized vs. non-pressurized
Term
non-pressurized systems include
Definition
flood and furrow
Term
pressurized systems include
Definition
-Over-the-canopy (sprinklers)
-Under-the-canopy (micro-jet, drip)
Term
plant factors affecting transpiration
Definition
1.) shape and orientation of leaves: affects degree of light interception
2.) Leaf area: the more stomata, the higher the transpiration rate
Term
Drip Irrigation emitters
Definition
1.) In-Line: placed inside the drip line at a predetermined spacing
2.) On-Line: manually placed in the line on the outside
Term
Height of above ground and below ground drip systems
Definition
-Above: 16-24 inches above floor
-Below: 18-24 inches buried
Term
What pressure do overhead sprinklers operate at?
Definition
30-50psi
Term
What pressure do micro sprinklers operate at?
Definition
15psi
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