EFFECTS OF MAIZE INTERCROPPING WITH LEGUMES ON FORAGE YIELD AND QUALITY

In order to study the effects of intercropping maize (Zea mays L.) with some legumes on forage yield and quality of maize, a two year field experiments was carried out based on randomized complete block design with three replications at the Agricultural Research Station, Faculty of Agriculture, University of Tabriz, Iran, during 2006-2007. Two maize hybrids (SC704, SC301), vetch (Vicia villosa), bitter vetch (Vicia ervilia), berseem clover (Trifolium alexandrinum L.) and common bean (Phaseolus vulgaris) sole crops as well as intercrops of maize hybrids with each of the legumes were used. Results of analysis of variance showed that dry matter (DM) yield of corn in intercropping with vetch and bitter vetch decreased. The corn dry matter yield loss in intercrop treatments in comparison with the sole crop of maize was 15.80 percentages. The study of forage quality characteristics indicated that maize ash and crude protein (CP) content in intercropping was increased because of having complementary effects in nutrients absorption. On the average of two years, the highest ash and CP content were achieved in intercropping of maize hybrids with berseem clover and bean. Amount of increase in ASH and CP for maize hybrids (704 and 301) in intercropping as compared to their monoculture was 9.43, 11.02, 14.52 and 18.42 percent, respectively. Thus, maize intercrops with bean and berseem clover had higher CP and also more CP yield in relation to its monoculture. The reason for this finding could be the larger transfer of fixed N from these legumes to maize and also smaller reduction of maize yield in intercropping with these legumes as compared with the vetch and bitter vetch.