Study of the role of cover crops on weed management and yield and its forage maize (Zea mays L.) components

Nowadays, planting cover crops to reduce herbicide use is advised. An experiment was conducted at Ardebil Agricultural and Natural Resources Research Station (at Samian) in the spring of 2012. Experimental design was a factorial arrangement based on a randomized complete block (RCBD) with three replications. The first factor was cover crop types including rye, hairy vetch, berseem clover, green pea and weed control treatment (no cover crop) and the second factor consisted of three levels of management including living mulch, bottom cutting mulch and cover crop topping from 20-30 cm height. Cover crops were planted between rows of KSC400 corn cultivar. The results showed that rye, hairy vetch and berseem clover and green pea could reduce the total density of weeds compared to the control by 76, 68, 65 and 55 percent respectively. The lowest weed biomass was in rye and vetch treatments with an average of 52.94 and 68.34 g m-2 respectively. The highest forage yield was 57500 kg ha-1 in weeding treatments and then 56450 kg ha-1 in hairy vetch. There was no significant difference between other cover crops. The results also showed that the living mulch management was the best in comparison to others with 52700 kg ha-1 forage yield production. The lowest yield was achieved in the control treatment without a cover crop, with 35000 kg ha-1 forage production. The results also showed that the highest fresh ear weight (32600 kg ha-1) was in the weed-free treatment, and then in hairy vetch at 31000 kg ha-1. The highest ear length (39 cm) was in the weed-free treatment too where there was no significant difference between hairy vetch and clover. The lowest ear length (28 cm) was in the control without any cover crop.