Agronomy - Study Mode
[#651] The major organic cementing agent in soil aggregate formation is
Correct Answer
(C) Polysaccharides
Explanation
Solution: Polysaccharides are the agent which binds the organic matter present in soil aggregate and improves the texture and binding ability of the soil. Soil is the mixture of sand, silt, gravel and crushed stone along with some organic matter which provides nutrition to the plants growing in that soil.
[#652] The element which does not enter into permanent organic combination in plants is
Correct Answer
(D) Potassium
Explanation
Solution: Potassium is the element that does not enter into permanent organic combination in plants because it is absorbed by the plants in a compound form not directly and it can be easily leached from nonliving plant tissue also.
[#653] Wheat crop yielding 50 quintals of grain per hectare removes N, P 2 O 5 and K 2 O kg/ha, respectively
Correct Answer
(A) 100-150, 70-80 and 125-150
Explanation
Solution: Nitrogen, phosphorous, and potassium are the essential nutrients provided to the soil for maximum yield, its mixture is also known as NPK fertilizer, it is a combination of all three in specific portions. In a wheat field, when the yield is 50 quintal/hectare, it uses NPK in ratios 100-150, 70-80 and 125-150 respectively.
[#654] Cropping pattern is defined as
Correct Answer
(C) The proportion of area under different crops at particular point of time
Explanation
Solution: A cropping pattern is a pattern followed to grow various crops in the same field at different proportions and at different points of time. This practice helps in maintaining the fertility of the soil with optimum utilization of resources, time-saving, and controlling the spread of disease and pests also.
[#655] Critical stage of maize crop is
Correct Answer
(B) Silking stage
Explanation
Solution: The critical stages of maize plantation are the Early vegetative, tasselling and silking stage but the most critical is the silking stage when the plant needs almost care about irrigation and nutrients. Corn is extremely sensitive to any stress which limits photosynthetic capacity if not taken care of at critical stages.