Intercropping as a low-input cropping systems have been associated with greater forage yield in comparison with sole crops. The aims of this study were to compare the forage yield of sole maize and intercrops of maize with legumes grown under biofertilizer application, and to examine different competition indices in these intercropping patterns. The field assay was conducted in 2013 growing season at the University of Maragheh located in East Azerbaijan province of Iran. This study was carried out in randomized complete block design (RCBD) with 14 treatments and 3 replications. Experimental treatments included intercropping of maize (inoculation with nitroxin as biological fertilizer) with hairy vetch (Vicia villosa Roth.), maize (no inoculation)-grass pea (Lathyrus sativus L.), maize (no inoculation)-sainfoin (Onobrychis vicifolia Scop.), maize (inoculated)-berseem clover (Trifolium alexandrinum L.), maize (no inoculation)-vetch, maize (inoculated)-vetch, maize (inoculated)-sainfoin, maize (no inoculation)+ berseem clover and monoculture of maize (no inoculation), maize (inoculation), clover, vetch, grass pea and sainfoin. Results showed that the highest forage production was observed in inoculated maize-vetch intercropping, while the lowest yield production was observed in sainfoin and grass pea sole crops. According to the findings of this research, the highest amounts of land equivalent ratio (LER) and monetary advantage index (MAI), belonged to inoculated maize-vetch intercropping. The higher relative crowding coefficient (K=1.08) values of Maize than legumes (K=0.93), indicating that maize was more competitive than legumes as intercrops. However, among all intercrops, the maize (inoculation)-vetch was found to be most profitable. Indeed, results from competition and economic indices indicated a superior advantage of this intercrop due to the better land use efficiency and better economy than the other evaluated intercrops.
