Assessment of Yield and Yield Components of Wheat Under Effect of Residue, Weed Control and Nitrogen Sources

In order to assess the influence of the plant residue management and application of different nitrogen sources and weed control on wheat yield and its components, an experiment was carried out at the Agricultural Faculty of Shahid Chamran University of Ahvaz during 2011-2012 with three replications. The experimental design was split-factorial based on randomized completed block design arrangement. The main plots were different wheat residue managements at three levels (residue moving,residue incorporated to the soil and burning) and the subplots were various nitrogen resources (control, 75 & 150 kg.ha-1 urea, Supernitroplus biological fertilizer (SNBF) and 75 kg.ha-1 urea fertilizer SNBF) and weed control at two levels (weed free and weed infested treatment). The result showed that the residue burning had the highest yield and yield components except for harvest index and the residue incorporated to the soil treatment was more effective than residue moving. Only the application of the biological fertilizer alone had no appropriate results but the use of biological with chemical fertilizer was more effective. The highest number of seed per spike and 1000 seeds weight were obtained at these treatments. The weed free treatments had positive effects on most traits than weed infested treatments. The highest grain yield (5.22 ton.ha-1) and the lowest (3.3 ton.ha-1) were obtained at residue burning and residue removing treatments respectively. Also, the weed free treatments had the highest (4.6 ton.ha-1) yield than weed infested (3.3 ton.ha-1) treatment. The results showed that with increasing levels of nitrogen, or a combination of biological and chemical fertilizer, Wheat Yield improved under incorporated residue treatment.