Nitrogen management in rice (Oryza sativa)-based food and fodder production system

A field experiment was conducted during 1987-88 to 1988-89 to study the effect of 6 redder crops along with wheat (Triticum aestivum L. emend. Fiori & Paol.)-common crop rotation used by the local farmers-on yield and nitrogen economy of succeeding rice crop (Oryza sativa L.). Six fodder crops were, viz. Egyptian clover (Trifolium alexandrium L.), oat (Avena sativa L.), Indian clover (Melilotus alba Desr.), lucerne (Medicago sativa L.), barley (Hordeum vulgare L. sensu late) and mustard (Brassica campestris L. var. Japan rape), along with wheat (grain) with recommended doses of fertilizers with an additional treatment of fallow in main plots during winter season. 'Jaya' rice was taken as succeeding rainy-season crop with 4 levels of nitrogen (0,40,80 and 120 kg N/ha) in subplots. The loamy soil was low in organic carbon and nitrogen. Among the various rice-based forage-cropping systems, the productivity of Egyptian clover-rice sequence was found maximum. This food-fodder cropping system also economized fertilizer N to the extent of 100 kg/ha with an additional amount of 20 kg P2O5/ha to legume component compared with to rice-wheat cropping system. Moreover, this system also improved the fertility status of soil.