Agronomy - Study Mode
[#431] Heat transfer in soil mainly occurs through
Correct Answer
(A) Conduction
Explanation
Solution: Transfer of heat in soil mainly occurs by the process of conduction. It is the process by which heat energy is transmitted through collisions between neighboring atoms or molecules. As we know soil is made up of particles, atoms and molecules, closely together to transfer heat.
[#432] High temperature of > 41°C at flowering of castor results in
Correct Answer
(B) Blasting of flower and poor seed-set
Explanation
Solution: Castor is a species of perennial flowering plant in the spurge family. It requires a hot, dry climate with an annual rainfall of 500 - 800 mm, of which 500 - 600 mm is needed during the first 3 months of crop growth. High temperatures above 41 degree Celsius at a flowering time even for a short period result in the blasting of flowers in Castor.
[#433] Sulfur content in SSP (Single Super Phosphate) is
Correct Answer
(A) 12%
Explanation
Solution: Single Super phosphate SSP is the first chemical fertilizer, it contains 3 major plant nutrients namely phosphorus, Sulphur, and calcium along with traces of micro-nutrients. It contains 14.5% of phosphorus, 12% of Sulphur and 21% of Calcium.
[#434] IRGA stands for
Correct Answer
(C) Infra-Red Gas Analyser
Explanation
Solution: IRGA stands for Infra-Red Gas Analyser and measures trace gases by determining the absorption of an emitted infrared light source through a certain air sample. The concept behind the technology is based on the amount of light absorbed by the air.
[#435] Contribution of flag leaf in photosynthates is about
Correct Answer
(D) 52%
Explanation
Solution: In gramineous plants, the first leaf below the inflorescence is called the flag leaf. The flag leaf is the last to emerge, which indicates the transition from the growth of the plant to grain production. Photosynthesis in these leaves provides the maximum of carbohydrates required for grain filling. Contribution of flag leaf in photosynthesis is about 52%.