Effect of green manuring and mineral fertilizer on growth and yield of crops in rice-based cropping on acid lateritic soil

Abstract

Summary Green manuring in situ with sunnhemp ( Crotalaria juncea ) and dhaincha ( Sesbania aculeata ) significantly improved growth and yield of transplanted rice. Giving the green manure crops 15 kg N/ha or 15 kg N and 30 kg P 2 O 5 /ha further increased yield. Interaction between green manuring and N fertilizer revealed that a considerable quantity of fertilizer N (45–60 kg N/ha) applied to rice could be replaced by incorporation of green manure crops to which a small amount of fertilizer had been applied. Residual fertility in terms of organic carbon and available N, P and K increased under green manuring, whereas N fertilizer made no impact on fertility build up. Grain yield of wheat and gram increased when grown after rice in plots which had grown green manure.