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Crop Science Test 1
Question | Answer |
---|---|
The first step in the development of an agricultural society was the | Beginning of subsistence agriculture |
Crop plants that are thought to have originated in the Americas include | Maize, white potato, and tomato |
Compared to 1968 (according to UN estimates) world agricultural production is now providing | More calories per person for more people on less land |
A below ground modified stem used primarily for asexual propagation is called | Rhizome |
The failure of an ordinarily upright stem to remain upright (fall over) is called | Stem lodging |
In its simplest form, photosynthesis can be divided into | Light and dark reactions |
The source of energy that is the product of the light reactions and provides energy to drive the dark reactions of photosynthesis is | ATP and NADPH |
The majority of carbon found on earth is in the form of | Fossil fuels and mineral carbonates (limestone) |
The point at which photosynthetic rate is equal to respiration rate is called the | Compensation point |
Light pigments that are best absorbed by chlorophyll and other plant pigments are | Blues and reds |
Essential flower parts include the | stamens and pistil |
A monoecious species | Has male and female flowers borne on the same plants |
A species of short day plant with a critical photoperiso of 14.5 hours is germinated and grown for two months in continuous light (24 hour photoperiod). After the light regime is changed to 16 hours light and 8 hours dakness per day. The plants would | Remain vegetative |
Flower structures common to both legumes and grasses are | Pistil and stamens |
The four major soil components are water, air, mineral matter, and | organic matter |
Soils are composed of four major parts: mineral components, organic matter, water, and | air |
The concentration of H+ ions in the soil | Can have a major impact on nutrient availability |
Hygroscopic soil water is | Water that is usually unavailible |
The most limitiing factor in agricultural production world wide is | water |
In spite of receiving a fairly amount of annual precipitation, water is often a limiting factor in crop production in Alabama and the Southeast because of | High evapotranspiration rates, poor water holding capacity of soils, and uneven seasonal rainfall distribution |
An important role of magnesium in the plant is | central in the structure of the chlorophyll molecule |
Ammonium nitrate (34-0-0) sells for $5.60 for a 50lb bag at the local co-op. The cost per pound of N would be approximately | $0.33 |
The major fertilizer material used to supply potassium in commercial fertilizers is | Muritate of potash, Potassium chloride |
Of the following, the only fertilizer material that is a commercial source of both N and P is | Monoammonium phosphate |
A 100lb bag of a fertilizer of grade (5-10-15) actually contains | The equivalent of 5lbs of N, 10lbs of P2O5, and 15lbs of K2O |
Give a specific example of a sink | developing fruit |
Give a specific example of a cross pollinated plant | soybeans |
Give a specific example of a Nutrient | Nitrogen |
Give a specific example of a commercial source of nitrogen fertilizer | ammonium nitrate |
Give a specific example of a modified stem | rhizome or stolon |
Give a brief description of a crop canopy | above ground portion of the crop |
Give a brief description of a stamen | pollen producing organ of a flower |
Give a brief description of a pollination | process which pollen is transferred in the reproduction of plants |
Give a brief description of a vernalization | plants ability to flower in the spring by exposure to the prolonged cold |
Give a brief description of net photosynthetic rate | the difference in the total amount of photosynthesis and the sum of the rates of respiration |
Explain the concept of apical dominance and include how it may relate to crop lodging and damage from hail or other types of upper plant injury | The phenomonen where the maincentral stem of the plant is dominant over other side stems. It can give the plant more support in bad weather conditions. |
Complete the following equation for photosynthesis ___ + 12H2O = 6H2O + 6O2 + glucose | 6CO2 |
Describe the relationship between dry matter accumulation and percent solar interception in crop plants | linear |
Indicate the availability of gravitation water to plants | Temporary but available |
Indicate the availability of capillary water to plants | very available |
Indicate the availability of hygroscopic water to plants | not available |
How do we correct (raise) the pH of an acid soil. | Spread lime |
Describe two crop management practices that can help improve water use effciency | irrigation scheduling what time of day to irrigate and irrigation system improvements to minimize water loss |
Piedmont Fertilizer Company in opelika has two fertilizer materials available for sale. A mixture of materials (0-20-20) is available at a cost of $240/ton., while (0-46-0) is $310/ton. What is the cost per pound of nutrient for each material. |