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

An experiment was conducted during 1991-92 and 1992-93 to evaluate the yiel d and economics of winter maize (Zea mays L.)-based intercropping systems u nder different fertility and weed-management systems at Pusa (Bihar). Maize grown with potato (Solanum tuberosum L.) in normal (1 : 1) and paired row planting (2 : 2) reduced the weed population, their dry weight and increase d the weed-smothering efficiency of crop canopy (66.10 and 60.59% respectiv ely). Maize intercropped with potato was more advantageous than French bean (Phaseolus vulgaris L.) and significantly improved all the yield attribute s as well as yield of component crops and finally recorded significantly hi gher maize-equivalent yield (12.30 and 12.02 tonnes/ha) than normal (1 : 2) and paired planting (2 : 4) of maize with French bean (9.81 and 9.65 tonne s/ha). On an average, maize intercropped with potato under normal and paire d planting systems, recorded 20.69 and 18.89% higher maize-equivalent yield than normal and paired row maize with French bean. Although gross return w as more with maize + potato, the net return and net return per rupee invest ment were higher in maize + French bean. The higher level of fertilizer res ulted in significant increase in all the yield attributes and yield of comp onent crops and ultimately the maize-equivalent yield. Net return was signi ficantly higher with 100% fertilizer dose but the net return per rupee of i nvestment was higher with 75% dose. Weedy ecosystem registered a yield redu ction of 29.63, 26.79 and 38.85% in maize, potato and French bean respectiv ely. Significantly higher maize-equivalent yield was recorded under hand-we eding and pendimethalin-treated plots than weedy check. Chemical weeding re corded significantly higher net return per rupee of investment.