. Soil Fertility and Crop Productivity as Influenced by Different Cropping Systems and Levels of Nitrogen in Central Plain Zone of Uttar Pradesh

Abstract

A field experiment was conducted during 1994-95 and 1995-96 at Kanpur on sandy loam soil to assess the beneficial effect of cereals and legumes on productivity of succeeding crop of mustard [Brassica juncea (L.) Czernj & Cosson] and their effects on soil fertility. The soil was low in available N and medium in available P and K. The seed yield of mustard was markedly higher after Sesbania cannabina compared with the mustard raised after fallow and other cereals and legumes. However, maize - mustard cropping system registered the maximum mustard equivalent yield (ME?), being higher over other cropping systems. The lowest MEY was obtained in fallow - mustard system due to single cropping. The yield of mustard and MEY increased with increasing levels of nitrogen up to 160 kg N/ha. Sesbania cannabina plots recorded higher organic carbon, available N, P and K m 0-15 cm soil layer over their initial status after two cycles of rotation. The organic carbon, available N, P and K status of soil in other legume plots were also higher compared with fallow-mustard and other cereals - mustard systems. Application of 160 kg N/ha to succeeding mustard after different crops augmented available N and K in soil.