Field Crop Section 3 review questions

What is the harvesting rule for rangeland where roots limit growth?

"take half, leave half, and your half will be larger."

List two production challenges of pulse crops in developing countries.

(1) Land preparation - a good seed bed is required and broadcast seed/rough tillage has an impact on yield, (2) weeds often out compete pulse crops, (3) low levels of phosphorus can impact N2 fixation, (4) soil pH - micronutrient deficiencies and toxicities often occur on acid soils, and (5) large numbers of pests and diseases.

Name two differences between yams and sweet potatoes.

(1) Yams have a rough, scaly brown skin, (2) flesh has more starch and is dry, (3) yam is a tuber, (4) yam is very low in vitamin A precursors, and (5) flesh color is white, yellow, and purple.

List the three trade-offs when harvesting perennial forages.

(1) root reserves (and stand life), (2) quality, (3) productivity (yield)

What are the four factors that influence regrowth?

(1) root reserves, (2) size of root system (esp. in water-limited enironments), (3) light interception (where root storage reserves are minimal and leaf photosynthesis is needed to drive regrowth), (4) growing points (don't cut off the active ones).

Give two examples of storage locations for the root reserves.

(1) roots, especially enlarged roots near the crown (alfalfa), (2) stem bases near the soil surface (timothy and other grasses), (3) stolons, and (4) rhizomes.

Cotton makes up what percentage of the global fiber market?

35 percent.

What is the generalized yield ratio for three alfalfa cuttings in the Great Lakes Region?

7:5:3

imothy is a popular grass in the Northeast because: a. Freeze tolerance b. High soil adaptability c. Survives in varying field conditions d. All of the above

A

What is a fistulated cow and why is the practice done?

A fistulated cow is an animal that has had a hole surgical made in its side that goes directly into the rumen; the rumen has been fused to the tissues of the animal's side to keep it in place. This process allows researchers to access the rumen fluids in the cow's rumen for rumen fluid studies.

What type of machine is used to plant soybeans in rows ranging from 15 to 36 inches?

A row planter; it is the same as used for corn.

What is meant by the term "short-day plant?"

A short-day plant needs a daylength shorter than its threshold value to induce flowering. Such plants typically flower in the latter half of summer when daylengths are getting shorter. This threshold is determined genetically, and we choose genotypes with a threshold value appropriate to the region in which it will be grown.

What continent is responsible for the greatest amount of plantain production?

Africa

.Cowpea is primarily grown on what two continents?

Africa and Asia

Describe the relationship between protein and fiber over time in alfalfa.

Answer: As the plant ages, protein levels decrease and fiber content increases.

Tall fescue should be grazed: a. All season long b. Later in the season c. Earlier in the season

Answer: Earlier in the season (poor quality as is matures)

The energy density of a lipid is how many times greater than a carbohydrate?

Approximately two times greater per gram of dry weight.

What are the two types of coffee varieties produced and traded globally?

Arabic and Robusta

Which continent produces the highest amount of sweet potato globally?

Asia

What country is the largest exporter of soybeans?

Brazil

After rice, wheat, and maize, what is the fourth most common staple crop produced globally?

Cassava

Amino acid complementarity occurs when pulses are eaten in combination with what other type of crop?

Cereals

What is the second most commonly traded commodity after crude oil?

Coffee.

What pulse crop often produces the lowest yields when compared to the other pulses discussed in lecture? Why?

Common bean generally has the lowest yields as a result of soil nutrient deficiencies and pest/disease pressures.

Describe the water needs for cotton during its growing stages.

Cotton requires low amounts of water during its initial growth stages; however, it requires the most amount of water during the flowering stage. Water requirement decreases during boll opening, particularly as high amounts of rainfall may damage fiber quality at this stage.

What pulse crop is typical grown and produced by women in developing countries?

Cowpea

Processing of cassava roots and leaves is necessary to remove what toxic chemical?

Cynogenic glucosides

What two environmental factors influence alfalfa quality?

Day length and heating degree-days influence the quality of alfalfa, but the stages of growth incorporate these environmental factors fairly consistently.

What are the two types of chickpea?

Deshi (90 percent of all production) and Kabuli.

Which pulse legume typically likes cool growing conditions?

Dried peas

Which pulse crop is the most important in terms of production and area?

Dry beans

What three pulse crops make up more than one-half of all pulse production?

Dry beans, chickpeas, and dry peas

Reed canarygrass only produces high yields on well-drained soils. a. True b. False

False, it can produce high yields on poorly drained soils

Kentucky bluegrass is not tolerant of close, continual use in pasture. a. True b. False

False, it is a species that is hardy enough for continual use or grazing.

Crownvetch is toxic to ruminants. a. True b. False

False, ruminants can tolerate the toxins present, but it is toxic to non- ruminants.

Plantains are rich in what nutritional components?

Fiber, potassium, magnesium, vitamin A and vitamin B.

During what growth stage is cassava most sensitive to drought?

First 3 months of growth

If a soybean line that is adapted to northern NY is sown in a more southerly location, would it flower later or earlier in southern regions? Why?

Flowering generally occurs earlier because the daylength hours at more southern latitudes are shorter.

What aspect of forage quality has the greatest influence on animal performance?

Forage intake

What are the two most important forage families?

Grasses and legumes.

Sweet potato is valued for what nutritional components?

High starch, fiber, calcium, vitamin A, and potassium.

Describe the difference between determinate and indeterminate soybean lines.

In determinate soybean lines (which are used in the southern USA), when flower initiation occurs, the plant stops growing leaves and stems at its apical meristem and flowering commences everywhere in the plant. In contrast, in indeterminate soybeans the plants continue to grow new leaves after flowers are initiated (in the axis of main-stem leaves). This soybean type is grown in the northern regions of the U.S.

What general effect do pulse-legume crops have on non-legume crops that are grown in the season following the planting of a pulse-legume?

In general, pulse-legumes help to increase the nitrogen availability in the soil for non-legume species, which typically has positive impacts on the yield of that crop.

96 percent of jute production is concentrated in what four countries?

India, Bangladesh, Nepal, and Myanmar.

List the top five pulse producing countries responsible for one-half of global pulse production

India, Canada, Myanmar, China, and Brazil

List the four components of forage quality.

Intake, digestibility, efficiency, and anti-quality. (IDEA)

How much nitrogen do soybean plants contribute to N depleted soils?

It can supply 100 percent. However, in more typical corn-soybean rotations, with good fertility, soybean supplies about 50% of N needs of soybeans.

What is the plantain pseudostem composed of?

It is composed of tightly packed leaf sheaths.

What fiber crop tolerates and even prospers at 100 degrees Fahrenheit?

Jute

Yam consuming areas tend to have higher incidences of what protein deficiency. What is this condition called?

Kwashiorkor

In terms of quality, which is generally higher: legumes or grasses? List two reasons.

Legumes are usually higher in quality. They are higher in quality because they have better digestibility and their NDF is lower

As plants age, what forage component increases and in what part of the plant?

Lignin concentration increases as plant tissues mature, and in plant stems it generally increases in absolute quantity per plant.

List the two types of lentil.

Macrosperma and microsperma

Sugarcane has requirements for what two nutrients?

Nitrogen and Potassium

What is the most limiting nutrient for cotton?

Nitrogen.

Are alfalfa leaves alone considered a forage?

No, in the context of animal feeds, they are not considered a true forage apart from their stems and are instead considered a concentrated feed (similar in composition to other high-protein feeds such as de-oiled soybean meal)

Is it necessary to inoculate soybeans with rhizobium bacteria every year?

No, it is not necessary. Generally, once the bacteria have been introduced into the soil, the bacteria survive year to year and it is not necessary to inoculate again if soybeans are planted within 2 to 3 years.

Which of the following is not considered a pulse crop: Cowpea, Peanut, Chickpea, or Lentil?

Peanut

Which pulse crop has the longest growing season?

Pigeon pea

List the four classes of sucrose that sugarcane produces.

Powdered, granulated white, brown, and turbinado.

What are pulses?

Pulses are leguminous crops that are generally used as dry grains as opposed to oils or vegetables like other legume crops.

Pulses contain how much more protein when compared to cereals?

Pulses have protein levels that are often two to three times higher than cereals.

What does the term 'retting' refer to?

Retting is the process of soaking the jute for at least 20 days in water and then peeling away the bark to separate the individual fibers.

Describe the symbiosis between microorganisms and livestock that occurs in the rumen.

Ruminant animals do not produce enzymes needed for breakdown of fiber components such as cellulose, hemicellulose, and lignin in forages. But their rumen hosts microorganisms that are able to digest these components into fatty acids and other nutrients the animal can use. In turn, these microorganisms receive nutrients and a desirable environment within the rumen.

List the two types of environments coffee is typically produced in and identify the environment that is considered to be more sustainable.

Shade-grown coffee is identified as being the more sustainable growing environment as coffee is grown in a more natural, forested environment as opposed to sun-grown monocultures.

Soybean composition is what percent oil and what percent protein?

Soybean seed is 20 percent oil, and 40 percent protein.

What is New York's fastest growing crop (in terms of production in US$)?

Soybeans

What is the main product of sugarcane?

Sucrose (for table sugar)

What starch staple crop has the highest level of vitamin A?

Sweet potato

Sweet potato has a long or short growing season when compared to other starch staples?

Sweet potato has a short growing season, ranging from 4 to 5 months.

Cassava contains high amounts of what nutritional component?

The Roots contain high amounts of starch. Leaves are edible as a green vegetable but also contain cyanogenic glucosides.

Which country is the top global exporter of cotton?

The U.S.

Jute fibers are obtained from what part of the plant?

The bark

What part of the plant cell corresponds to neutral-detergent fiber (NDF)?

The cell wall.

What is the ideal stage to cut alfalfa in order to maximize quality?

The ideal cutting time is when alfalfa is between the late bud and early bloom stages.

Where is the majority of soybean production centered in the U.S.?

The largest area of production is the corn belt.

Soybean plants are likely to have a greater amount of pod set on what part of their morphology during early flowering?

The main stem of the plant where flowering begins first.

What is the most accurate test for forage quality? List a disadvantage of this test.

The most accurate forage quality test is the rumen fluid test (in vitro digestion). However, this test is not normally done because the test takes a long incubation period (48 hours), and it requires a source of rumen fluid from animals kept in specific conditions.

What is the start of the most critical growth stage in soybeans for yield determination? What are the yield components determined at this stage?

The start of the most critical growth stage is R4. The yield components include the pods per plant, the seeds per pod, and the seed weight.

If range grasses such as little bluestem are grazed closely and continuously, what happens to the roots?

They do not grow as dense and as deep, thereby having poor performance in water-limited environments.

Name the big five grasses.

Timothy, smooth bromegrass, orchardgrass, reed canarygrass, and tall fescue.

List several reasons farmers tend to plant extra seeds.

To compensate for poor seed quality or seedling vigor, poor germination emergence, seedling disease, herbicide injury, insects, hail, and poor cultivation.

Jute is used to make what types of products?

Twine, rope, matting, bags, and carpets.

Switchgrass is a native species commonly used for biomass/biofuel. a. True b. False

a

When compared to the other big five, tall fescue is the highest yielding forage. a. True b. False

a

What two forage species can you harvest closely, but not often?

alfalfa and timothy

Alsike clover is a hybrid of white and red clover. a. True b. False

b

Smooth bromegrass is non-spreading species. a. True b. False

b

Which of the following forage legumes is not commonly used for hay? a. Alfalfa b. White clover c. Red clover d. Alsike clover

b

In timothy and smooth bromegrass, what is the critical management period?

between jointing and boot stage (when the stem is telescopically elongating and pushing the inflorescence upward; at this stage the buds near the soil surface are inactive)

Redtop is a perennial grass commonly used for what special purpose? a. Pasture b. Turf c. Conservation d. A and B

c

Which of the following is a characteristic of orchardgrass? a. Spreading species b. High quality forage c. Early maturity d. Uncompetitive in pastures

c

The most important forage grass worldwide is: a. Redtop b. Kentucky bluegrass c. Timothy d. Perennial ryegrass

d

What type of planter is used for soybean in 7 inch row spacing?

drill planter, which is also used for small grains such as wheat.

Why is it critical that light reach the crown of the plant?

growing points need light to stimulate them for regrowth

As a short day plant, what range of sunlight hours do yams require for optimal tuber growth? What occurs if yams receive more than this optimal range of sunlight?

he ideal sunlight hour range is between 10 to 11 hours. After 12 hours of sunlight or more, the plant places more energy in vine growth rather than tuber development.

What is the ideal soil pH range for most pulse crops?

pH 6 to 7.

Define root reserves.

storage nonstructural carbohydrates in the root or stem bases, usually starch, fructan (polymer of fructose), or sugars (in tropical grasses).

Define critical leaf area index.

the LAI needed to intercept 95% of the incoming solar radiation

What is the regrowth rule with regards to growing points?

there must be active growing points for regrowth to occur.