Midterm Study Guides

Question 1

How many GDD would accumulate during a 24-hour period where the low temperature was 60 and the high was 74 for a corn crop? (60 as base temperature)

Answer 1

17

Question 2

What is the formula used to calculate Growing Degree Days (GDD)?

Answer 2

(Maximum Temperature + Minimum Temperature)/2 - Base Temperature (usually 60)

Question 3

Nutrient Deficiency symptom: yellowing along tip and edges, lower leaves

Answer 3

Potassium

Question 4

Nutrient Deficiency Symptom: yellowing starts at tip and moves along midrib

Answer 4

Nitrogen

Question 5

Nutrient Deficiency Symptom: reddish-purple in young leaves

Answer 5

Phosphorous

Question 6

Drought symptoms:

Answer 6

rolled leaves: grayish green

Question 7

Corn Hybrid Improvements

Answer 7

• withstand higher populations
• more vertical leave angle
• reduced tassel size
• close timing silking and pollen shed
• increased stay green
• more starch
• altered root architecture
• water use efficiency

Question 8

Current record for bu/a

Answer 8

350-355 bu/a

Question 9

Kinds of corn: starch shrinks and dries, forming dents

Answer 9

Dent corn

Question 10

Kinds of corn: hard starch/kernals that form ornamental ears

Answer 10

Flint corn

Question 11

Kinds of corn: soft starch which makes flour and corn shells

Answer 11

Flour corn

Question 12

Kinds of corn: very hard, resists steam, smaller kernal

Answer 12

Popcorn

Question 13

Kinds of corn: dry and wrinkled, high in sugar

Answer 13

Sweet corn

Question 14

Kinds of corn: dull, starch quality

Answer 14

Waxy corn

Question 15

Kinds of corn: primitive features

Answer 15

Pod corn

Question 16

Types of corn growth stages

Answer 16

Vegetative and Reproductive

Question 17

VE

Answer 17

Emergance

Question 18

V1

Answer 18

1st Leaf Collar
Growing point below soil
Tassel and ear shoots initiated
Seed rows set

Question 19

V3

Answer 19

three leaf collars are very obvious

Question 20

V12-16

Answer 20

kernals/ear (size of ear)

Question 21

VT

Answer 21

Tassel (2-3 days before silking)
(pollen lives 24 hrs)
(pollen shed 1-2 wks)

Question 22

R1

Answer 22

Silking (coming out of ear - every kernel develops a silk)

Question 23

R2

Answer 23

Blister (10-14 dy) white on outside

Question 24

R3

Answer 24

Milk (18-22 dy) inner fluid now milky (starch building)

Question 25

R4

Answer 25

Dough (24-28 dy) inner fluid now thick/pasty

Question 26

R5

Answer 26

Dent (35-42 dy) dented kernels

Question 27

R6

Answer 27

Black layer (55-65 dy) dark layer on corn kernel indicates maturity for harvest

Question 28

What can delay seed emergence?

Answer 28

soil compaction cold soil herbicide injury fertilizer injury

Question 29

Corn insect: small, bluegreen, pear shape with black tail pipes. Known for sucking sap and speckling on leaves/stems

Answer 29

Leaf aphid

Question 30

Corn insect: yellow with black stripes. Known for chewing, plants lodge, destroy silks, poor pollination (attacks roots and silks)

Answer 30

Corn rootworm

Question 31

Corn insect: chews edges, ragged leaves

Answer 31

Grasshopper

Question 32

Corn insect: off white with grey line down back and two brown spots. Known for tunnels, shot holes in leaves (attacks stem)

Answer 32

European corn borer

Question 33

Which growth stage represents the grain filling period in corn?

Answer 33

R 1-2

Question 34

Durum Wheat

Answer 34

Used for pasta, low gluten

Question 35

White Wheat

Answer 35

Used for rolls, tortillas Hard white winter Soft white winter

Question 36

Soft Red Wheat

Answer 36

Used for pastries, cakes, crackers | Soft Red Winter (light brown with red tints)

Question 37

Hard Red Wheat

Answer 37

Used for bread Hard Red Winter Hard Red Spring

Question 38

The primary function claimed for bacterial non-protein inoculants used as silage additive is to:

Answer 38

increase fermentation rate and efficiency

Question 39

Autotoxicity in alfalfa production is the result of toxins from

Answer 39

the alfalfa plant itself

Question 40

Which harvest method for alfalfa has the highest field loss associated with harvesting?

Answer 40

field cured hay

Question 41

Aflatoxins in corn can affect livestock by causing

Answer 41

liver damage

Question 42

The odorless, colorless, heavy poisonous gas that can develop as a layer on the surface during filling of upright silos and causes lung damage is

Answer 42

Nitrogen dioxide

Question 43

An indeterminate growth habit soybean ________.

Answer 43

continues to flower and grow vegetatively simultaneously

Question 44

A higher number for the ADF and NDF forage test scores result in a ___________ RFV score and _________ quality.

Answer 44

lower, lower

Question 45

Which statement represents the best quality corn silage? 1. silage "cut" should be 1 to 1 1/2 inches 2. harvest silage at the milk stage of corn kernels so yield is highest 3. corn grain content contributes at least 50% of the energy 4. silage in a bunker will pack best at 40-45% moisture

Answer 45

3. corn grain content contributes at least 50% of the energy

Question 46

What percentage of the flowers that develop on soybean plants can be expected to abort or fail to form pods?

Answer 46

60-75%

Question 47

Which factor has the greatest influence on flower initiation in soybean?

Answer 47

temperature

Question 48

Which fatty acid is considered the most desirable by the foot industry for cooking foods?

Answer 48

oleic (unsaturated)

Question 49

List all oilseed crops:

Answer 49

flax safflower canola sunflower

Question 50

List all pulse crops:

Answer 50

dry pea lentil chickpea

Question 51

Corn growth peaks at _____.

Answer 51

86 degrees Fahrenheit