Effects of Cover crop residue management on corn yield and weed control

The use of cover crops can be considered as an effective method in sustainable agriculture through reducing herbicide use, improving soil and increasing crop yield. An experiment was conducted using randomized complete block design with three replications in Agricultural and natural resources research center of Ardabil (Moghan) in 2015-2016. Cover crops was considered as the main factor (mixed wheat + crimson clover, monoculture wheat and mixed (rye + wheat)) and mulch management as subplots and control (no cover crop use post-emergence herbicide Maister (Foramsulfuron + Idosulfuron 3.1% OD)). The results showed no significant difference between treatments in terms biomass production, the lowest weed biomass was related mixed of rye + wheat in both crop management methods. In wheat and wheat+ rye a significant decrease was observed in crop yield components possibly due to the release of allelopathic materials and soil properties, But the crimson clover mix of wheat + maize yield satisfactory beside weed control a good yield was obtained after the treatment with herbicide. The results showed that the effect of cover crop, crop management and their interaction except grain weight, were significant for ear dry weight, biological yield, number of rows per ear and number of kernels per ear. The highest values of grain yield, ear dry weight, biological yield, number of grains per ear was achieved in treatments clover + wheat and the least amount of yield and yield components of treated wheat was obtained in residues removed management.