Yield and economics as influenced by wiier maize (Zea mays)- based intercropping systems in North Bihar

Abstract

An experiment was conducted during 1991-92 and 1992-93 to evaluate the yield and economics of-winter maize (Zea mays L.)-based intercropping systems under different fertility and weed-management systems at Pusa (Bihar). Maize grown with potato (Solanum tuberosum L.) in normal (1 : I ) and paired row planting (2 :2) reduced the weed population, their dry weight and increased the weed-smothering efficiency of crop canopy (66.10 and 60.59% respectively). Maize intercropped with potato was more advantageous than French bean.(Phaseolus vulgaris L.) and sig- nificantly improved all the yield attributes as well as yield of component crops and finally recorded significantly higher maize-equivalent yield (12.30 and 12.02 tonnesl ha) than normal (1 : 2) and paired planting (2 :4) of maize with French bean (9.81 and 9.65 tonneslha). On an average, maize htercropped with potato under normal ,-_ and paired planting systems, recorded 20.69 and 18.89% higher maize-equivalent yield than normal and paired row maize with French bean. Although gross return was more with maize + potato, the net return and net return per rupee investment were higher in maize + French bean. The higher level of fertilizer resulted in significant increase in all the yield attributes and yield of component crops and ultimately the maize-equivalent yield. Net return was significantly higher with 100% fertilizer dose but the net return per rupee of investment was higher with 75% dose. Weedy eco- system registered a yield reduction of 29.63,26.79 and 38.85% in maize, potato and French bean respectively. Significantly higher maize-equivalent yield was recorded under hand-weeding and pendimethalin-treated plots than weedy check. Chemical weeding recorded signicantly higher net return per rupee of investment.