Effect of crop residue management, application of compost and nitrogen fertilizer on grain yield and its components in maize cv. DC370

Effect of wheat residues, nitrogen fertilizer levels, compost and weed control on agronomic characteristics and grain yield and its components in maize (cv. DC370) was studied in 2008 and 2009 cropping seasons at Bajgah Agriculture Research Station, Shiraz University, Shiraz, Iran. The experiment was conducted as a splitsplit plot arrangement in randomized complete block design with three replications. Two levels of weed control (weedy and weed free) were assigned to main plots and three levels of N fertilizer rates 0, 125, 250 kg.ha-1), and five organic matter application methods (0, 25 and 50% of wheat residue incorporation, 50 and 100 ton.ha-1 of compost application) were randomized in sub-plots and sub-sub-plots, respectively. Application of 125 kg.ha-1 of nitrogen fertilizer produced the highest weed biomass and N loss (2450 and 25.17 kg.ha, respectively). Grain yield was significantly affected by compost and N fertilizer application and the highest grain yield (9404 kg.ha-1) was obtained with 100 ton.ha-1 of compost and 250 kg.ha-1 of nitrogen fertilizer. Crop residue incorporation and N fertilizer also increased grain yield, but not at the level of compost and N fertilizer.Compost application was often better than residue incorporation in terms of organic matter enhancement in two depths of soil (0-15 and 15-30 cm). Therefore, application of compost with high inorganic N fertilizer could have contaminant potential for ground water. Although positive aspects of application of compost were often more pronounced than residue incorporation, but the latter is more safe and inexpensive.