Effects of Nitrogen Top-Dressing applied at Full Heading Stage and at Pollen mothercell meiosis stage of Rice

Abstract

Nitrogen top-dressing applied at full heading stage was found less influential in increasing yield than top-dressing applied. at the Panicle primordia initiation stage or at pollen mother cell meiosis stage in nothern district of Japan. The reason is supposed that in this district, increasing yield of rice is especialy due to increasing number of ears per plant or number of spikelets per plant which are increased by top-dressing applied at pollen mother cell meiosis stage (top-yield) or at the panicle primordia differentiating stage, whereas the increasing yield does not directly connect with increasing seed setting rate and decreasing trash rice. It is noticed that white-core grain percent (white-core grain has long been appreciated by brewers in Japan) is increased by nitrogen top-dressing applied at the full heading stage with decreasing trash rice.