Yield and chemical composition of cowpea (Vigna unguiculata) fodder as affected by tillage practices and nitrogen management

Abstract

A field experiment was laid in split plot design with three replication for evaluating fodder cowpea under different tillage and nitrogen management practices. The experiment consisted of three contrasting tillage practices viz., zero tillage (ZT), conventional tillage (CT) and raised bed (RB) as main plots and six N management treatments viz., 0, 75% N, 75% N + Rhizobium, 100% N, 100% N + Rhizobium and 125% N as sub plot treatments. Among tillage practices, significantly (P<0.05) higher green (241.11 q/ha) and dry fodder yield (41.50q/ha) was recorded in treatment RB over CT (220.57 and 37.0 q/ha) but fodder yield in treatment RB was at par with ZT (234.76 and 39.90 q/ha). However, total-CHO content was lower (P<0.05) in treatment RB. Among N management options, higher green (P<0.05) fodder yield was recorded in treatment 75% N + Rhizobium (250.19 q/ha) over 75% N (224.85 q/ha) and 0% N (179.21 q/ha) but 75% N + Rhizobium was at par with 125% N (247.63 q/ha), 100% N + Rhizobium (248.39 q/ha) and 100% N (242.63 q/ha). The fodder quality parameters were not affected by tillage practices. Significantly (P<0.05) higher values of DM, TA, CP and lower value of NDICP (DM %), cell content, total-CHO, NDF and cellulose content were recorded in 125% N treatment over 100% N, 75% N + Rhizobium, 75% N and 0% N treatments but the values in 125% N treatment were at par with 100% N + Rhizobium treatment. However, lower (P<0.05) values of NDICP (% CP), ADICP (% DM and % CP), ADF and hemicellulose content were also observed in 125% N treatment compared to 75% N + Rhizobium, 75% N and 0% N treatmenst but 125% N treatment was at par with 100% N and 100% N + Rhizobium. Hence, cowpea grown under ZT/RB with application of 100% N + Rhizbium inoculation improved yield and quality of fodder cowpea.