Effect of integrated nutrient management on the performance of sole and intercropped pigeonpea (Cajanus cajan) under rainfed conditions

A field experiment was conducted during kharif seasons of crop years (July-June) 2008-09 and 2009-10 at Varanasi to find out the effect of integrated nutrient management (INM) on the growth, yield, economics, nutrient uptake and balance sheet of sole and intercropped of pigeonpea Cajanus cajan (L. ) Millsp. and blackgram Vigna mungo (L. ) Hepper in 1: 1 normal planting (60 cm spacing) and 2: 2 paired row planting (40/80 cm). Inter- cropping system had significant effect on gross returns, net returns, B: C ratio and monetary advantage index (MAI), total uptake of N, P, K, S and Zn, when compared to sole pigeonpea. Higher values of gross returns, net re- turns, B: C ratio and MAI were recorded under normal intercropping system followed by paired intercropping sys- tem. Significantly higher values of total uptake (N, P, K, S and Zn) was recorded under sole pigeonpea. The lowest negative value of actual gain of S and Zn was recorded under paired intercropping. Among the integrated nutrient management, application of 100% RDF + 50% of RDN through vermicompost + 5 kg Zn/ha gave significantly higher growth and yield attributes, grain yield, gross returns, net returns, B: C ratio, MAI and total uptake (NPKS and Zn) of both crops. The lowest N/P/K/S efficiency ratio and physiological efficiency index of cropping systems were recorded under application of 100% RDF + 50% NVC + 5 kg Zn/ha followed by 50% RDF + 100% NVC + 5 kg Zn/ha. Application of 100% RDF + 50% NVC + 5 kg Zn/ha recorded significantly higher total uptake and avail- able soil S and Zn after harvest of crop. Maximum negative value of actual gain of S and Zn was also recorded with the application of 100% RDF + 50% NVC + 5 kg Zn/ha.