Soil Science - Study Mode
[#296] The particle density of clay soil is
Correct Answer
(C) 2.83 gm/cm 3
Explanation
Solution: Particle density is the density of the solid particles that collectively make up a soil sample. The value is commonly expressed in grams per cubic centimeter. The common range of all the soils is 2.55 to 2.70 grams per cubic meter. The particle density of clay soil is 2.83 gm/cm 3 .
[#297] Low temperature & high rainfall is conducive for accumulation of
Correct Answer
(D) OM
Explanation
Solution: Low temperature and high rainfall are conducive for the accumulation of OM.
[#298] Typhoons derive their energy from
Correct Answer
(D) Latent heat of vaporization
Explanation
Solution: Typhoons are tropical storms with wind speeds of at least 74 miles (119 kilometers) per hour just like a hurricane. Typhoon derives their energy from Latent heat of vaporization of water from the ocean surface, which ultimately condenses into clouds and rain when moist air rises and cools to saturation. Thus the main source of energy for typhoons is the Ocean both by direct heat transfer from their surface and by the evaporation of water.
[#299] Which one is most toxic?
Correct Answer
(B) Dialdrin
Explanation
Solution: Out of the given options of pesticides, Dieldrin is the most toxic insecticide and is now banned also due to concerns about their impact on human health. It increases the threat of breast cancer. Dieldrin was widely used as a pesticide for corn, cotton and citrus crops. It persists in the soil with a half-life of five years at temperate latitudes.
[#300] Blossom end rot disorder in tomato has been found to be caused by the deficiency of
Correct Answer
(B) Ca
Explanation
Solution: Blossom end rot of tomato is a physiological disease and is caused by the deficiency of Calcium in the plant. It can occur in both green and ripe fruits and is identified by water-soaked areas that gradually widen and mature into sunken, brown, leathery spots on the bottom end. This disease can be eradicated by adding high levels of calcium like bone meal, oyster shell or gypsum.