Yield and Economics of Maize (Zea mays) + Soybean (Glycin max L. Merrill) Intercropping System under Different Tillage Methods

A study was conducted to determine the most profitable crop arrangements for maize and soybean intercropping system. The effect of tillage {conventional (CT) versus zero tillage (ZT)} and six crop arrangements (sole maize, sole soybean, maize+soybean intercropping at different row ratio arrangements) on grain yield and economics was investigated in Chitwan, Nepal during the summer of 2013. The grain yields of maize and soybean were not affected by tillage methods. However, crop arrangements significantly affect yield component and yield of both maize and soybean. Sole crop of maize and soybean recorded significantly higher grain yield than corresponding yields under intercropping systems. Planting maize+soybean at 1:1 ratio recorded highest maize grain yield (4.58 Mg ha-1) and 2:2 ratio recorded the highest soybean yield (1.70 Mg ha-1). Yield reduction due to intercropping ranged from 21.44% to 31.9% in maize and 22.3% to 53.88% in soybean as compared to their sole cropping. Remarkably higher net return was obtained in ZT (NPRs 110.4 thousands ha-1) than CT (NPRs 105.8 thousands ha-1). Intercropping of maize and soybean at 2:2 ratio recorded maximum benefit (NPRs 132.7 thousands ha-1), maize grain yield equivalent (8.74 Mg ha-1) and land equivalent ratio (1.47) than sole and intercropping treatments. It was found that paired rows of soybean between two rows of maize under ZT system could achieve higher productivity and profitability.