Term
What are the 3 types of Growth Habits? |
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Definition
Winter - requires cold exposure (-4C) to switch V to R
Spring - no vernilization needed
Facultative - short period of exposure to cold speeds up flowering but is not required |
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Term
Why is Winter wheat better than Spring? |
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Definition
Can withstand freezing tempertures
Efficient water utilization
Early heading - no insecticides needed
High yield potential
Good weed competitor |
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Term
What are the 2 important physiological changes during fall and winter? |
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Definition
Vernilization - reproductive growth enabled from exposure to cold temperture
Cold Acclimation - winter hardiness is induced. Allows plant to survive sub-zero temperatures |
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Term
How is vernilization genetically controlled? |
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Definition
vrn - recessive winter
Vrn - dominant spring
Vrn A > Vrn B > Vrn D
Frost tolerance is Fr and vrn A |
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Term
How is cold hardiness genetically controlled? |
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Definition
Induced by temperatures less than 10C
Change with time, temperature, day length, etc. |
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Term
What metabolic changes are associated with winter hardening? |
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Definition
Cold-hardened cells have a dense cytoplasm and small vaucoles |
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Term
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Definition
Upwards swelling of soil during freezing caused by ice |
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Term
How can you improve winter survival rates? |
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Definition
Norstar wheat
Plant at optimum dates
Soil phosphorous levels
Seeding depths |
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Term
Why is snow cover important? |
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Definition
prevents soil temperature from getting too low
prevents against dehydration |
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