Question

what are the causes of net sown area under cereals and pulses

Answer 1

Lodging of Crops

Lodging of grass and cereal cropsoccurs as they near maturity because their tall stems are pushed sideways by the wind. Failure may occur when the stem buckles (stem lodging) or when the root system rotates in, or is pulled out of, the soil (root lodging, Ennos, 1991). Plant breeders have developed cultivars with shorter, stiff stems to resist stem lodging, and farmers also may apply growth regulating chemicals to reduce stem elongation, but these strategies cause greater forces to be transmitted to root systems and may make root lodging more prevalent. Lodging is most likely to occur when the weight of the upper parts of plants is increased by the interception of rain, when the lower parts of stems are weakened by disease or by a heavy application of nitrogenous fertilizer, or when the shearing strength of the soil around the roots is weakened by rainfall. Tani (1963) investigated the forces needed to bend the stems of rice beyond their elastic limit. Ennos (1991)measured forces associated with stem bending and root anchorage in mature spring wheat (Triticum aestivum) grown in the laboratory.