Agronomy 280 Exam 2 | Questions And Answers Latest {2024- 2025} A+ Graded | 100%
Verified
When looking at the equation Yield = Genotype + Environment + Interaction of Genotype and
Environment, why is the interaction important? - Both of these answers are important reasons why GXE
is important
When talking about 6 plus 2 or 4 plus 1 in a seed corn production field, what are "2" and "1" referring
to? - Number of male rows
Inbreeding depression is the term used to describe: - decreased performance when corn is continually
self-pollinated
Using the backcrossing breeding method is only useful when selecting for GMO traits. - False
Hybrid vigor or Heterosis is the term used to describe: - Increased performance of a hybrid compared to
the inbreds that produced it.
Most hybrids and varieties on the market took more than 5 years to be developed by plant breeders. -
True
Seed production of self-pollinated crops typically ____ require separate male and female rows. - does
not
When two inbred lines are crossed to form hybrid seed, the plants from that seed will be: -
Homogeneous
Which of the following is a true statement about the difference between generating open-pollinated
and hybrid corn? - Hybrids cannot be maintained by open pollination
Which crop should be planted first based on what calendar dates are associated with significant yield
loss? - Oats
, How many pounds of pure live seed are in a 60 lb bag of seed if the purity is 99% and the germination is
97% - 57.618
Nitrogen has two ionic forms that can be taken up by crops. Due to its negative charge, ____ is repelled
by clay minerals making it more mobile in the soil compared to ____, which has positive charge. -
Nitrate, Ammonium
Calculate total Phosphorus removal throughout a corn-soybean rotation cycle if corn yielded 215 bu/a
and soybean yielded 62 bu/a. Corn removal factor is 0.32 lb P205/bu and soybean removal factor is 0.72
lb P205/bu. Report your result as lb P205/a. - 113.44
A farmer has two distinct fields. Field A has well-drained, moderately-eroded upland soils. Field B has
highly fertile, but poorly-drained alluvial soils. She currently applies 160 lb N/a to both fields, and
achieves 204 bu/a in Field A and 190 bu/a in Field B. After running several years of strip trials you have
determined that the economic optimum is almost the same for both fields, at about 210 lb N/a. The
yield at the economic optimum in Field A is 213 bu/a, while in field B it is 196 bu/a. The farmer tells you
that she only has enough money to buy 50 lb N/a of additional fertilizer. Which field do you recommend
should receive the extra 50 lb N/a in order to maximize economic return? - Field A
Soil tests for a field indicate that soil P concentrations are in the "very high" category. How probable is it
that we will obtain higher yields by adding P fertilizer? - Unlikely
Soybean has taken up about ____ of its total nitrogen requirement by the beginning of pod
development (R3 stage) - 40% Or50%
Sulfur in the form of (SO4)1 - is considered ____ in the plant and ____ in the soil - somewhat mobile,
mobile
Nitrogen in the form of (NH4)+ is considered ____ in the plant and ____ in the soil. - mobile, immobile
Magnesium in the form of (Mg)2+ is considered ____ in the plant and ____ in the soil - somewhat
mobile, immobile
Historically, Iowa was a major oat producing state. - True
Verified
When looking at the equation Yield = Genotype + Environment + Interaction of Genotype and
Environment, why is the interaction important? - Both of these answers are important reasons why GXE
is important
When talking about 6 plus 2 or 4 plus 1 in a seed corn production field, what are "2" and "1" referring
to? - Number of male rows
Inbreeding depression is the term used to describe: - decreased performance when corn is continually
self-pollinated
Using the backcrossing breeding method is only useful when selecting for GMO traits. - False
Hybrid vigor or Heterosis is the term used to describe: - Increased performance of a hybrid compared to
the inbreds that produced it.
Most hybrids and varieties on the market took more than 5 years to be developed by plant breeders. -
True
Seed production of self-pollinated crops typically ____ require separate male and female rows. - does
not
When two inbred lines are crossed to form hybrid seed, the plants from that seed will be: -
Homogeneous
Which of the following is a true statement about the difference between generating open-pollinated
and hybrid corn? - Hybrids cannot be maintained by open pollination
Which crop should be planted first based on what calendar dates are associated with significant yield
loss? - Oats
, How many pounds of pure live seed are in a 60 lb bag of seed if the purity is 99% and the germination is
97% - 57.618
Nitrogen has two ionic forms that can be taken up by crops. Due to its negative charge, ____ is repelled
by clay minerals making it more mobile in the soil compared to ____, which has positive charge. -
Nitrate, Ammonium
Calculate total Phosphorus removal throughout a corn-soybean rotation cycle if corn yielded 215 bu/a
and soybean yielded 62 bu/a. Corn removal factor is 0.32 lb P205/bu and soybean removal factor is 0.72
lb P205/bu. Report your result as lb P205/a. - 113.44
A farmer has two distinct fields. Field A has well-drained, moderately-eroded upland soils. Field B has
highly fertile, but poorly-drained alluvial soils. She currently applies 160 lb N/a to both fields, and
achieves 204 bu/a in Field A and 190 bu/a in Field B. After running several years of strip trials you have
determined that the economic optimum is almost the same for both fields, at about 210 lb N/a. The
yield at the economic optimum in Field A is 213 bu/a, while in field B it is 196 bu/a. The farmer tells you
that she only has enough money to buy 50 lb N/a of additional fertilizer. Which field do you recommend
should receive the extra 50 lb N/a in order to maximize economic return? - Field A
Soil tests for a field indicate that soil P concentrations are in the "very high" category. How probable is it
that we will obtain higher yields by adding P fertilizer? - Unlikely
Soybean has taken up about ____ of its total nitrogen requirement by the beginning of pod
development (R3 stage) - 40% Or50%
Sulfur in the form of (SO4)1 - is considered ____ in the plant and ____ in the soil - somewhat mobile,
mobile
Nitrogen in the form of (NH4)+ is considered ____ in the plant and ____ in the soil. - mobile, immobile
Magnesium in the form of (Mg)2+ is considered ____ in the plant and ____ in the soil - somewhat
mobile, immobile
Historically, Iowa was a major oat producing state. - True
