Interaction of Nitrogen Fertilizer and Wheat Density in Competition with Wild Barley under Metsulfuron methyl + Sulfosulfuron Doses in Karaj and Qom

Field experiments were conducted to study the effect of nitrogen, wheat density and herbicide doses on wheat-wild barley competition in Karaj and Qom. Experiment was a split-factorial with three replications. Experimental factors were wheat densities of 300, 400 and 500 plants m-2, nitrogen levels of 240 and 300 kg ha-1 and five doses of metsulfuron-methyl plus sulfosulfuron at 0, 20, 33, 45 and 54 g ha-1. Results from both locations indicated significant interactions between treatments. Depending on herbicide dose applied wheat density effect on wild-barley biomass was different. Decrease in wild-barley biomass obtained from increasing wheat density was significantly higher with low doses of herbicide. Regarding higher nitrogen efficiency in Karaj wheat, lower nitrogen level caused more competition ability of wheat and lower wild-barley biomass. In Qom experiment, the general trend was similar, differences were not significant at p-value