Effect of intercrop and crop geometry on productivity, economics, energetics and soil-fertility status of maize (Zea mays)-based intercropping systems

A field experiment was conduced during the rainy seasons of 2003 and 2004 at Kalimela, Orissa, to study the effect of intercrops and crop geometry on productivity, economics, energetics and soil-fertility status of maize (Zea mays L.)-based intercropping systems under rainfed condition. lntercrop blackgram (Phaseolus mungo L.) followed by soybean [Glycine max (L). Merr.] was found better than groundnut (Arachis hypogaea L.), whereas the row ratio 1:1, followed by 2:2 proved better than 2:l with respect to productivity, economics and energy out- put. Maize with soybean and blackgram with maize significantly recorded he highest maize-grain equivalent yield of 25.7 and 11.8qlha at 1:l row ratio respectively. Among various intercropping systems, maize+blackgram at 1 :I row ratio significantly achieved the maximum maize-grain equivalent yield (37.5 qlha), land-equivalent ra- tio (1.68), area-time equivalent ratio (1.61), monetary advantage index (9,102), net return (Rs 10,51 Ilha), return1 rupee invested (1.84) and energy output (144.2, 1000 MJIha) compared to sole maize and blackgram. Maize+soybean at 1:l row ratio closely followed this system on the above aspects. Groundnut proved compat- ible, remunerative and less competitive with maize at 2:2 ratio rather than at 1 :I and 2:l row ratios. Intercropping increased available soil N and decreased both soil P and K compared to initial and available soil N, P and K content after sole maize at both the systems of sowing. Available soil N, P and K content varied with the kind of intercrops. However, maize+soybean followed by maize+blackgram recorded the highest available soil N at 1:l row ratio and available soil P and K at 2:l row ratio among various intercropping systems.