Response of sweet Sudan grass (Sorghum sudanensis) to cowpea (Vigna unguiculata) intercropping and nitrogen levels in arid region of Rajasthan.

摘要

A field experiment was conducted at the experimental farm of Central Sheep and Wool Research Institute, Arid Region Campus, Bikaner, Rajasthan, India, during summer season of 2001 to 2003, to determine the effect of cowpea intercropping and different levels of nitrogen (N) on the productivity and economics of sweet Sudan grass (Sorghum sudanense) in the arid region. The treatments comprised three cropping systems, viz., sweet Sudan grass (SSG-788) sole, cowpea (EC-4216) sole, and SSG+cowpea in the main plots and four levels of N (control, 80, 120 and 160 kg N/ha) in the subplots. A basal dose of 10 t/ha of sheep manure (contained 230 kg N, 83 kg P2O5 and 160 kg K2O) alongwith 40 kg P2O5/ha through single superphosphate and 30 kg K2O through muriate of potash was applied to each plot. Results revealed that the green forage (50.4 t/ha) and dry matter (13.14 t/ha) yields recorded with SSG+cowpea system were 12.5 and 9.32% higher over SSG alone, respectively in addition to 6.1-7.1 t/ha of protein-rich cowpea fodder. Application of 10 t/ha of sheep manure+N fertilizer at 160 kg/ha produced significantly higher green forage and dry matter yields over lower levels. Higher energy ratio (6.88), energy productivity (382.1 g/MJ), net return (Rs. 24 915) and benefit-cost ratio were recorded with SSG+cowpea than SSG or cowpea alone..