Efficient nitrogen management for sustained productivity in lowland rice (Oryza sativa)

Abstract

A study on rice (Oryza sativa L.) made during 1987-90 at Cuttack under shallow-submerged situation in an alluvial sandy-loam soil revealed that integrated N-management system involving a combination of organics, viz. green-manures or Azolla compost or farmyard manure (FYM) or water-hyacinth compost and inorganics each source meeting 37.5 kg N/ha gave comparable yields to the application of 75 kg N/ha as inorganic N alone. During dry season, at a suboptimal level of 40 kg N/ha, 2-equal split applications (at active tillering and panicle initiation or planting and panicle initiation) proved superior. During wet season at 20 kg N/ha, 2-equal split applications (at planting and tillering or active tillering and panicle initiation) were more ideal. During wet season, single basal application of urea coated with Mussorrie rock phosphate or gypsum or neem (Azadirachta indica L.) at 30 and 60 kg N/ha gave similar yield as that of conventional 3-split application.