AGRONOMY
114 EXAM
2 NAME:
____________________________
1.
Soil organic matter
a)
decreases soils structure
b)
increases soil texture
c)
influences on soil structure and increases
soil porosity
d)
lowers micronutrient supply to crop plants
e)
releases CO2 needed for root photosynthesis
2.
Loam soils are generally better suited to orchard
production than silty clay soils because loam soils
a)
are 'heavier'
b)
usually
have weaker structure
c)
have slower water infiltration
d)
have better internal drainage
e)
are better suited to furrow irrigation than
3.
Susan didn't get her corn crop planted at the
optimum planting date last year. In an
effort to accelerate the growth rate of corn seedlings, she decided to put
fertilizer with seed at planting time (pop-up).
She ended up with a very poor stand of corn after using 30 lb/A nitrogen, 30 lb/A potassium and 30 lb/A phosphorous as a
pop-up fertilizer. What went wrong?
a)
plant the seed wasn’t deep enough for the
fertilizer to be activated
b)
the total amount of nitrogen and potassium
was too great to use as a pop-up fertilizer
c)
only nitrogen can be used in pop-up fertilizer
d)
only potassium can be used in pop-up fertilizer
e)
the extra weight of the fertilizer on the
planting machine undoubtedly caused her to plant too deep
4.
Due to a late snow storm, a farmer was not
able to plant oats until the first part of May, a time that is considered late
in the season. Should the farmer plant a higher than average population to
maximize the yield potential?
a)
no, because tillering
would likely fill in the stand and make up for planting late
b)
yes, because tillering
would not produce enough seed-bearing stems make up the yield loss due to late
planting
c)
no, because oats is a warm season crop and
therefore late planting should not be a problem
d)
yes, and the oats should be planted with a
row crop planter to allow more light availability for tillering
e)
no, because high populations of oats should
only be planted in fertile soils that have plenty of moisture
5.
Selfing
a crop
a)
moves traits toward homozygosity
b)
moves the offspring toward heterogeneous
populations
c)
moves the alleles toward homogenous
populations
d)
results in poorer performing varieties
e)
improves the heterosis
of a self-pollinating variety
6.
Grain merchants at the Chicago Board of Trade
are interested in Iowa’s late fall subsoil moisture status. Why?
a)
they want to make polite conversation with
Iowans
b)
the fall subsoil, moisture is an indicator of
how well the ground will freeze during the winter to kill some pathogens
c)
fall soil moisture is an early indicator of
the soil moisture available to plants the following spring
d)
fall
subsoil moisture influences winter wheat survival & yields.
e)
they know Iowans enjoy talking about the
weather
7.
Your aunt and uncle bought a farm in southern
Soil Dakota, and plan to grow corn under irrigation. They want to irrigate and maximize the
water-use efficiency of their crop. Which of the following combinations should
have the greatest water-use efficiency?
a)
wide row spacing and low populations
b)
narrow row spacing and high populations
c)
wide rows spacing and high populations
d)
narrow row spacing and low populations
e)
wide row spacing and medium populations
8.
The primary purpose of State Crop Improvement
Associations are due to:
a)
ensure the availability of high quality crop
seed
b)
maintain active crop breeding programs to
produce breeder seed
c)
ensure that all crop seed sold is state
certified
d)
breed new crops and improve crop varieties
e)
oversee the production of genetically
engineered crops
9.
Younger soils, generally have
a)
less profile distinction
b)
well developed surface drainage
c)
more defined B horizons
d)
been developed under forest vegetation
e)
hilly topography
10.
If a poor stand of soybeans occurred from a late
planting on a clean-tilled soil, the most likely reason would be
a)
lack of oxygen
b)
poor seed-to-soil contact
c)
dormant seed
d)
warm soil temperatures
e)
lack of soil moisture
11.
An Oklahoma farmer wanted to minimize soil
erosion and minimize soil water evaporation. Which primary tillage operation
should one use
a)
moldboard plow
b)
chisel plow
c)
a sweep plow or rodweeder
d)
an offset disk
e)
listing
12.
Plant A is TTRr. Plant B is TtRR. TT or Tt = tall, tt =short, RR or Rr
= red, rr = white.
If A is crossed with B, what portion of the F1 generation will be short
and white?
a)
100%
b)
75%
c)
50%
d)
25%
e)
0%
13.
Which of the following best represents
labeling requirements for selling crops for seed in the U.S.?
a)
private variety label
b)
patented variety label
c)
U.S. No. 1 yellow soybeans label
d)
seed label
e)
special grade label
14.
"Selfing"
a pure line variety (genotype: TT) for 3 generations would probably result in a
a)
heterogenous
population
b)
slight increase in heterosis
c)
slight decrease in male sterility
d)
segregating population in the F3
e)
population the same as what you started with
15.
The process of inserting genes or pieces of
DNA from one species is called
a)
gene transfer
b)
gene splicing
c)
recombinant DNA technology
d)
genetic engineering
e)
all of the above
16.
Which of the following crop management
practices would be least advisable during a year with low subsoil moisture?
a)
plant at normal plant populations
b)
plant more drought tolerant varieties
c)
increase the amount of tillage in cropping
system
d)
consider irrigation
e)
use of a mulch
17.
Early dates of planting usually result in
higher yields other factors being equal because
a)
plants have less vapor pressure deficits
b)
have less total seasonal light interception
c)
seedlings emerge faster following planting
d)
have a greater LAI earlier in the season
e)
use less of the growing season because of
early maturity
18.
The success of "delayed seedbed
preparation" depends upon
a)
waiting until the crop seedlings are firmly
established
b)
tilling to a depth of 6 inches or less
c)
not bringing new-weed seeds to the surface
d)
acceptance by the farmer of "minimum
tillage philosophy"
e)
tilling fast enough to "throw"
small weed seedlings out of the soil while injuring few crop seedlings
19.
In the cells of a leaf of a given grass
species the normal number of chromosomes is 20 (2n = 20). The following statement about this species is
true
a)
a cell in the scutellum contains 30
chromosomes
b)
a pollen cell contains one nucleus with 20
chromosomes
c)
a cell in the endosperm contains 30
chromosomes
d)
a cell in the endosperm contains 20
chromosomes
e)
a cell in the embryo axis of the seed
contains 10 chromosomes
20.
What nutrient would be most limiting to high
yields of non-nodulating soybeans in an alluvial type
soil in Minnesota when no fertilizer is applied to the field?
a)
P
b)
K
c)
CA
d)
Fe
e)
N
21.
This conservation tillage system has been
primarily used in areas deficient in rainfall.
This system forms a furrow on non-plowed soil and plants seed in the
furrow in one operation. This system is called
a)
lister-planting
b)
strip-till planting
c)
strip-rotary tillage
d)
till-plant on ridged soil
e)
no-till on non-ridged soil
22.
The production of a synthetic variety
involves
a)
a polycross progeny
test
b)
the controlled crossing of two self
pollinating species
c)
the use of cytoplasmic-genetic male sterility
to produce the synthetic
d)
the controlled crossing of four inbreds to produce two single crosses
e)
pedigree selection to produce pure lines that
are bulked to produce a multiline
23.
Most corn is bought and sold on a bushel
basis (56 lbs/bu). However, some farmers in the Ames
area are bringing in corn with a test weight of 50 lbs/bu. If these farmers are hauling in 28,000 pounds
of corn per load and corn is bringing $5.00 per bushel, what is the load worth
in approximate dollars (without discounts)?
a)
$1566
b)
$2100
c)
$2250
d)
$2500
e)
$2800
24.
During the formation of gametes in the seed
plant, which of the following occur?
a)
meiosis
b)
mitosis
c)
formation of male or female gametes
d)
the chomosome
number changes from diploid to haploid
e)
all of the above
25.
The following statement is true for
"hold-over" cotton seed (seed that is not planted the year after
production and is to be planted the following year) as compared to fresh seed
a)
the seedling vigor is likely to be decreased
b)
the germination percentage is more likely to
be near that of field emergence
c)
the germination percentage is likely to be
increased
d)
the seedling vigor in cold tests is likely to
be increased
e)
the resistance to seedling diseases is likely
to be increased
26.
Which is true?
a)
total pore space in soil is influenced by
rainfall patterns
b)
clay soils are better drained and aerated
than soils with large non-capillary pores
c)
soil porosity refers to total pore space
minus the portion of pore space occupied by water
d)
macropores
are normally filled with water
e)
clay soils have a high proportion of small
capillary pores
27.
The following statement about fungi is true.
a)
fungi are usually not found in good Iowa soil
b)
fungi cannot be seen by the naked eye
c)
fungi will usually out compete bacteria in an
acid soil
d)
fungi are one celled organisms
e)
fungi do not damage plants
28.
Soils developed under grass as you go west
from Iowa toward Colorado would be expected to
a)
gradually increase in acidity
b)
have CaCO3 at increasingly deeper depths
c)
gradually decrease in pH
d)
have organic matter at shallower depths
compared to soils east of Iowa
e)
be wetter
29.
If the effective rooting depth of millet is 4
feet in a silt loam soil that holds 1 1/2 inches of available water per foot depth
of soil, and millet uses 0.1 inches of water per day in evapotranspiration,
then how long would it take the soil to reach wilting point without rainfall?
a.
2.7 days
b.
10 days
c.
15 days
d.
45 days
e.
60 days
30.
In dryland wheat areas
of the world, sufficient soil moisture is often a concern. Fields are sometimes left fallow for a year to
conserve moisture, however, managing weeds is a problem. What type of tillage system would be most
beneficial to conserve moisture and manage weeds in the fallow field?
a)
conventional tillage system
b)
sweep tillage system
c)
chisel plow system
d)
disk tillage system
e)
ridge tillage system
31.
Which nutrients are generally more available
in slightly and moderately acidic soils?
a)
iron, calcium and copper
b)
nitrogen, potassium and phosphorus
c)
potassium and iron
d)
boron and calcium
e)
iron, boron and copper
32.
The accelerated aging test is generally
conducted to test seedling vigor. Under
what conditions are the seeds placed for this test?
a)
seeds are exposed to cool temperatures and
allowed to germinate under warm conditions
b)
seeds are dipped in tetrazolium
and then allowed to germinate
c)
the seeds are soaked in sodium hypochlorite
for 2-3 days and then allowed to germinate under optimum conditions
d)
the seeds are exposed to high temperatures
and relative humidity for 3 to 4 days and then allowed to germinate in optimum
conditions
e)
the seeds are stored for 3 years and then
placed in a seedbed and allowed to germinate in optimum
33.
Some legume species produce "hard
seed". The reason for this term
being used in reference to these seeds is because
a)
the seed coat remains hard and does not
imbibe water
b)
the seeds are "hard" to handle
because of their very small size
c)
the seeds are filled with SiO2 instead of an
embryo which makes the seed physically hard
d)
the seed is "hard" to harvest due
to its large size
e)
the "hard seed" of legumes are
"hard" to find available in the seed market
34.
In general, micronutrient deficiencies would
be least likely to occur in soils that have
a)
a high sand content
b)
been intensively cropped for many years
c)
a very high pH
d)
an average amount of organic matter
e)
been intensively cropped in tropical forest
regions
35.
Which of the following should the farmer be most interested in for calibrating planting rates?
a)
germination percentage
b)
pounds of seed per bushel
c)
cost per pound of seed
d)
purity
e)
pure live seed
36.
What is the most significant contribution of
soil organic matter?
a)
its influence on soil structure and
increasing soil porosity
b)
increasing the parent material
c)
the black color which absorbs heat and warms
up the soil
d)
the salt content of the organic matter which
increases the osmotic pressure of the soil solution
e)
the reduction of the available water in the
soil at the permanent wilting percentage
37.
If seed of a crop species had immature
embryos and is bought and sold on a pure live seed basis, the greatest profit to
a seller would be to
a)
clean it, bag it and sell it as soon as
possible
b)
don't clean it, instead, bag it and sell it
as soon as possible
c)
clean it, bag it and store it before selling
it
d)
sell it "as is" to the buyer in the
fall
e)
sell it when price is agreed upon
38.
A few days after irrigating his clover field,
a farmer noticed that the red and white clover were
wilting in his field of saline-sodic soils. What would likely be the cause of the clover
wilting?
a)
the crop does not have enough water
b)
the soil particles hold more water at wilting
point
c)
red and white clover is sensitive to saline
soil conditions
d)
salts have increased the osmotic
concentration of the soil solution
e)
all of the above
39.
When soil holds moisture with a tension or
suction of the outer surface of the water film at 15 atmospheres or 15 bars,
then
a)
the plant will start to show signs of wilting
b)
the gravitational water begins to decrease
c)
the plant will be able to absorb soil
moisture at the maximum rate
d)
cell turgor will increase
e)
the permanent wilting point will likely be
reached
40.
The majority of farmers who grow maize in the
United States buy their seed from seed dealers.
Why do they buy their seed rather than saving their grain from the
previous year?
a)
the second year's crop from saved seed would
be inbreds and produce a homogenous population
b)
the saved seed would pollinate each other
(self-pollinate) and the crop would exhibit undesirable genotypes
c)
the farmers want to support the seed industry
so that the companies will continue to sell
d)
the crop from the saved seed would be
homozygous and homogeneous
e)
maize is generally a self-pollinating crop
and the saved seeds would produce a crop of inbred plants
41.
What crops would likely grow best in soils
with a pH of 5.1?
a)
red clover
b)
beets
c)
maize and alfalfa
d)
blueberries and white potatoes
e)
blueberries and soybeans
42.
A farmer wishes to apply 160 pounds of
nitrogen per acre to a summer annual grain crop. Which soil type would more likely require two
applications, a preplant application followed by a sidedressing later in the season?
a)
sandy loam
b)
silt loam
c)
clay loam
d)
granular
e)
silty
clay loam
43.
Cropping systems affect soil structure. Under which cropping system would you likely
find a greater proportion of aggregates in the soil?
a)
clover in a two-year rotation of clover and maize
rotation
b)
continuous clover for hay
c)
continuous maize with conservation tillage
d)
continuous tall grass, native prairie species
e)
maize in a soybean-maize rotation using
no-till
44.
The equation P = G + E is often used to
explain variability among plants. Which
of the following statements about this is true?
a)
E modifies P
b)
P is a symbol that represents plants
c)
E represents the portion of heritability that
cannot be explained by inheritance and environment
d)
plant breeders genetically manipulate E to
obtain the greatest plant improvement
e)
G = P + E
45.
An effect well known to corn producers is
that corn grain yield may drop from 10% to 25% when grown in a continuous corn
system. Studies by researchers in Minnesota
have demonstrated that this loss of yield in continuous corn is due to some
harmful chemical substance that is produced by the corn itself. What is the correct name of this effect?
a)
symbiosis
b)
rotation effect
c)
zero till toxicity
d)
allelopathy
e)
hypogeal emergence
46.
Seed generally are planted deeper in the soil
a)
if they are smaller seed
b)
if the soil is sandier
c)
if the soil temperatures are lower
d)
if the soil moisture content is higher
e)
if the seeds are more egg-shaped
47.
"Triple fusion" is a process
associated with
a)
hygroscopic water shells
b)
formation of endosperm
c)
the pedigree method of breeding
d)
tsunamis
e)
blending of breeder's, foundation and
certified seed
48.
Suppose an interior grain elevator loaded 50
grain cars with No. 2 Yellow Corn and 50 grain cars with No. 4 Yellow Corn on a
100-car train bound for a river terminal under contract for delivery at $5/bu for No. 2 Yellow Corn. Which statement is logical or
correct?
a)
Corn will arrive at the river terminal at No.
3 grade
b)
Corn will arrive at the river terminal at a
No. 2 grade at a price of $2.50/bu
c)
The interior elevator will empty the 50 cars
of No. 4 grade and reload with No. 2 grade yellow corn before shipping
d)
The terminal elevator will accept the 100
cars of grain at a No. 2 price.
e)
The terminal elevator will accept all the
grain as sample grade but at the stated price.
49.
A farmer in western Nebraska who irrigates
his crops would desire
a.
Higher vapor pressure deficits
b.
Higher transpiration ratios
c.
Higher respiration rates
d.
Smaller LAI
e.
Crops with a deeper root system.
50.
To germinate, seeds need a correct amount of
moisture, oxygen and temperature. Some species also require light to
germinate. Which of the following
species commonly grown in the Midwest require light for germination?
a)
maize and soybeans
b)
Kentucky bluegrass and tobacco
c)
sunflower and tomatoes
d)
lettuce and sweet potatoes
e)
peas and pumpkin
AGRONOMY 114 EXAM 2,
Item # Answer
1 3
2 4
3 2
4 2
5 1
6 3
7 2
8 1
9 1
10 5
11 3
12 5
13 4
14 5
15 5
16 3
17 4
18 3
19 3
20 5
21 1
22 1
23 4
24 5
25 1
26 5
27 3
28 4
29 5
30 2
31 5
32 4
33 1
34 4
35 5
36 1
37 3
38 5
39 5
40 2
41 4
42 1
43 4
44 1
45 4
46 2
47 2
48 3
49 5
50 2