Productivity and Economic Assessment of Maize and Soybean Intercropping under Various Tillage and Residue Levels in Chitwan, Nepal

Abstract

A field experiment was conducted at National Maize Research Program (NMRP) in Rampur, Chitwan, Nepal during May-Nov 2013. The experiment was laid out in strip- split design with twelve treatments and three replications. Treatments consisted of two different tillage methods namely conventional tillage (CT) and zero tillage (ZT) as vertical factor, two different levels of residue (residue kept and residue removed) as horizontal factor and three different levels of cropping systems namely sole maize, sole soybean and maize + soybean intercropping system as sub plot factor. Manakamana-3 and Puja were the variety of maize and soybean used for the experiment respectively. The results revealed that the grain yield and yield attributing components of maize and soybean was significantly influenced by cropping systems but not by tillage methods and residue levels. The grain yield of maize obtained under sole cropping (4.76 t ha-1) was significantly higher than maize + soybean intercropping system (4.27 t ha-1). Similarly, the grain yield of sole soybean was significantly higher (1.99 t ha-1) than that of maize + soybean intercropping system (1.26 t ha-1). Moreover, the total grain yield equivalent of 6.45 t ha-1 obtained from sole soybean system was significantly higher and was followed by maize and soybean intercropping system with 4.99 t ha-1. Whereas, sole maize produced significantly the lowest maize grain yield equivalent of 3.47 t ha-1. Significantly, higher LER (1.38) was recorded with maize and soybean intercropping system over sole system (1.0). Tillage and residue levels did not affect the gross and net return and B: C ratio but the effect was found obvious due to intercropping system. Significantly higher net return (NRs.140.49 thousands ha-1) was recorded in intercropping of maize with soybean as compared to sole soybean (NRs. 89.85 thousands ha-1) which was at par with sole maize system (NRs. 80.91 thousands ha-1). Maize and soybean intercropping system produced significantly the higher (2.47) B: C ratio than sole soybean (2.28) and was at par with sole maize (2.18).