Effect of integrated nitrogen application and spacing on yield of rice (Oryza sativa) in foot-hill soils of West Bengal

The effect of integrated use of fertilizer nitrogen along with Gliricidia leaves @ 10 tonnes/ha as green-manure and spacing was examined in a field trial with rice (Oryza sativa L.) during the wet season of 1999 and 2000. Application of green-leaf manure improved yield attributes, grain and straw yields of rice. Each unit increase in N level led to significant increase in yield-attributing characters and yield of rice. The maximum grain yield was recorded with the highest level of N. The nitrogen-use efficiency and apparent nitrogen recovery (%) were significantly higher at lower level of N and decreased significantly with increasing N levels. Closer row spacing (15 cm x 15 cm) proved better in grain and straw yields of rice, nitrogen-use efficiency and nitrogen uptake than the wider row spacing (20 cm x 15 cm).