Effect Nitrogen Management on Panicle Structure and Yield in Rice(Oryza sativa L.)

ABSTRACT: Nitrogen fertilizer is a major essential plant nutrient and key input for in increasing crop yield, This experiment was carried out in randomized complete block desing with 3 replication in 2006 growing seasons. Main polt was nitrogen rates including(100,200 and 300kgN/ha) applied as urea and sub plot was split application at three levelT1(1/2basel-1/2mid tillering), T2(1/3basel-1/3mid tillaring-1/3panicle initiation) and T3 (1/4basel-1/4 mid tillering-1/4panicle initiation-1/4 flowering). The results showed that panicle number, panicle length, panicle dry matter, number of primary branches, total grain and grain yeild, increased significantly with nitrogen fertilizer. Application 300kg/ha N-fertilizer observed high rate of this parameter. Effect of different split application N-fertilizer were significantly on this parameter, this parameter increased significantly with increase split application but the maximum number of panicle number and total grain weight obseved in3 split application. study intraction effect of treatment‘s revealed that the panicle length at harvesting stage and total grain increased significantly with an application of 300 kg/ha N-fertilizer at four stage. According resulted of this study panicle structure such as number of panicles (heads) spikeler density, panicle length, panicle curvature and the number of grains per panicle are determined by the nitrogen application.