EFFECT OF FERTILIZER AND PLANT-DENSITY MANAGEMENT ON PRODUCTIVITY ANDECONOMICS OF MAIZE (ZEA-MAYS) PLUS BLACKGRAM (PHASEOLUS-MUNGO) INTERCROPPING

A field experiment was conducted during rainy season of 1988 and 1989 on sandy-loam soil to study the effect of fertilizer and plant populat ion of blackgram on productivity of maize (Zea,,lays L.) + blackgram ( Phaseolus mungo L.) intercropping. Separate fertilization (fertilizer for component crops applied separately to respective rows) gave 8.4% h igher grain yield of maize than uniform fertilization (fertilizer for component crops mixed together and applied uniformly in rows irrespect ive of crops). Reduction in population of blackgram as an intercrop be low 100% decreased the productivity of tile system. Grain yield of int ercropped maize was almost similar (4.O4-4.18 tonnes/ha) to its sole c rop (4.32 tonnes/ha) when grown with 100% population (20 kg seed/ha) a nd 50 (10 kg N and 8.8 kg P/ha) to 100% (20 kg N and 17.6 kg P/ha) fer tilizer to blackgram and component crops fertilized separately. This c ombination also gave higher grain yield (0.82-0.84 tonnes/ha) of the i ntercrop blackgram, suggesting that 50% fertilizer to blackgram could be saved without any significant reduction in production potential of the system. Maize + blackgram intercropping system with 100% populatio n and 50% fertilizer to blackgram and fertilized separately to both th e component crops gave maize-equivalent yield of 5.88 tonnes/ha and ne t return of Rs 10 470/ha.