Influence of nitrogen and Crop density on Spring Wheat (Triticum aestivum L.) yield, yield components and wild oat (Avena Ludoviciana L.) suppression

A field study was conducted to determine the effects of different levels of nitrogen and crop density on yield, yield components and wild oat (Avena Ludoviciana L.) control. The treatments were nitrogen fertilization (100, 150 and 190 kg nitrogen ha-1) and crop density (400, 500, 600 and 700 plants m-2) of spring wheat, grown under high weed pressure. The experimental design was factorial with three replications. Result showed that increase of nitrogen and higher wheat densities were able to suppress wild oat biomass production. Nitrogen fertilization increased weed biomass and it increased grain yield and number of spikes, number of grains per spike and 1000grain weight. At the highest crop density, weed biomass, number of grain per spike and 1000-grain weight less than the lowest density. In addition, increased crop density had a positive effect on a number of spikes m -2 and wheat grain yield. The highest 1000-grain weight and weed biomass were obtained with lowest crop density and high nitrogen fertilization. The results indicate that increased nitrogen fertilization and crop density had a positive impact on the competitiveness of wheat and wild oat suppression.