Effect of Organic and Inorganic Nutrient Sources on Growth, Yield, Nutrient Uptake and Economics of Fodder Cowpea [Vigna unguiculata (L.) Walp.]

An experiment was conducted to evaluate the varying organic and inorganic nutrient sources on fodder cowpea [Vigna unguiculata (L.) Walp.] in the kharif of 2017 at ICAR-NDRI, Karnal. The result revealed that application of 100% RDF (N,P,K) along with biofertilizers (rhizobium, PSB, potassium and zinc solubilizer bacteria) (T-6) gave significantly (P<0.05) higher in plant height (204.6 cm), primary branches (6.1), root length (24.47 cm), green matter yield (334.5 q ha(-1)), CGR (8.13 g m(-2) day(-1)), RGR (4.68 g g(-1) day(-1)), K content (1.45%) in plant, P uptake (23.01 kg ha(-1)) and K uptake (86.04 kg ha(-1)) and available Zn status (0.465 ppm) in soil, after harvesting of the crop. However, N content (2.93%) in plant, N uptake (172.51 kg ha(-1)) and Zn uptake (192.03 g ha(-1)) was maximum with the application of 66.67% RDF along with biofertilizers consortium (T-7). Application of 100% RDF along with PSB (T-3) recorded highest number of nodule (33), P content in plant (0.389%) and available P status (24.76 g ha(-1)) in soil, after harvest. Further studies that, available N status (208.03 kg h(-1)), K status (221.27 kg ha(-1)) in soil, after harvest and Zn content (33.31 ppm) in plant were significantly higher with these treatments like T-8 -15 N, 60 P2O5, 40 K2O kg ha(-1) along with rhizobium, T-4-100% RDF along with K solubilizer and T-11-FYM 5 t ha(-1) with biofertilizers, respectively. In context of the economics of fodder cowpea production, highest gross return (Rs. 53525 ha(-1)) was obtained from T-6 while maximum net return (Rs. 31351 ha(-1)) and benefit-cost ratio (1.45) were worked out maximum with the treatment T-7.