Effecf of organic and inorganic source of nitrogen on growth, yield and nutrients uptake under cowpea-unseed cropping system

The field experiment was conducted to study the effect of organic manures on crop performance and soil properties. The maximum piant height at 45 days, number of branches/plant, and dry matter yield of cowpea were recorded with treatment CT₄ (37.5 kg N/ha) in 1992 and CT₁₆ (22.5 kg N/ha) in 1993. The maximum plant height at 45 days, number of tillers/plant, capsules/plant, dry matter production and grain and straw yield of linseed crop were recorded with LT16 (FYM 7.5 t + 37.5 kg N/ha) in 1992–93 and 1993–94. The maximum uptake of N, P and K by cowpea plant was noted with CT₄ (37.5 kg N/ha) in 1992 and CT₁₆ (22.5 kg N/ha) in 1993. But, sulphur uptake by cowpea plant was the highest under CT₄ (37.5 kg N/ha) in 1992 and 1993. The maximum uptake of N (grain and strawl, P and K by straw of linseed was recorded with LT₁₆ (FYM 7.5 t + 37.5 kg N/ha) in 1992–93 and 1993–94. Whereas, uptake of sulphur by linseed was the highest with LT₁₆ (FYM 7.5 t + 37.5 kg N/ha) in 1992–93 and LT₄ (75 kg N/ha) in 1993–94. Although, the uptake of P and K was similar in linseed grain with the treatment LT₁₃(FYM 6 t +30 kg N/ha) and LT(FYM 7.5 t + 37.5 kg N/ha) in 1992–93. FYM was found superior to dhaincha and subabul.