Impact of stand density and levels of nitrogen on yield maximization and N utilization of rice (Oryza sativa) under deepwater situation.

摘要

A field experiment was conducted during the 2002 and 2003 wet seasons in Cuttack, Orissa, India, to study the effect of stand density (high at 150 cm2 hill- at 15x10 cm spacing; medium or normal 300 cm2 hill- at 15x20 cm spacing; and low at 450 cm2 hill- at 15x30 cm spacing) and N fertilizer rates (0, 40, 60 and 80 kg/ha) on the yield and N utilization of rice cv. Sarala. Low density stand gave significantly high grain yield (2.56 t/ha). In addition, the application of different N rates showed the highest grain yield (3.15 t/ha) with an optimum rate of 60 kg N/ha, which derived maximum N use efficiency (27.12 kg grain/kg N), N uptake (0.46 kg/ha) and N recovery (16.81%). N at 60 kg/ha combined with low density stand produced the highest grain yield (3.40 t/ha)..