Effect of intercropped kharif legumes with bt cotton on seed cotton yield, economics and soil fertility

A field experiment was carried out during kharif season of 2007–08 on medium deep black soil at Cotton Improvement Project, Mahatma Phule Krishi Vidyapeeth, Rahuri to find out the best profitable Bt cotton based intercropping system under rainfed condition. Experimental results revealed that treatment Bt cotton+soybean (1: 1) recorded significantly more seed cotton yield (17.83 q/ha) closely followed by Bt cotton+greengram (1: 1) (16.93 q/ha) as compared to sole Bt cotton (15.27 q/ha). All the intercropping treatments were at par with each other in respect of seed cotton yield. The highest seed cotton equivalent yield (21.37 q/ha), net returns (Rs. 23150/ha) and B: C ratio (1: 1.89) over sole Bt cotton (15.25 q/ha, Rs. 10075/ha and 1: 1.40, respectively) were also acrrued with the treatment Bt cotton+greengram (1: 1). Nitrogen status in soil increased with all legume intercropping treatments compared to sole Bt cotton.