Green manuring in rice-wheat cropping system - A review

Sesbania aculeata had the maximum number, fresh and dry weight of root nodules per plant followed by Vigna unguiculata and Crotalaria juncea. The number of nodules and its weight increased with increase in age of the crop and were maximum at the age of 8 weeks after sowing. The N additions through these green manures were 65.5–137.6, 84.2–121.2 and 739–1280 kg per hectare respectively. Incorporation of Sesbania, Crotalaria or Vigna green manure increased plant height, number of shoots m−2 and dry matter accumulation per hill in rice. Yield attributes of rice viz number of panicles, number of filled spikelets per panicle; panicle length and 1000 grain weight were maximum with Sesbania green manuring. Grain and straw yield of rice and wheat under rice wheat rotation system, with Sesbania green manure was greater as compared to other green manuring sources. There was increase in organic carbon, and N, P, and K contents in the of soil due to the application of green manures.