The Effect of Split Application of Nitrogen and Herbicide Doses on Yield and Yield Components of Wheat in Competition with Weeds
Subject Areas : Journal of Crop EcophysiologyR. Mohaghegh Nezhad, 1 , M. Armin 2 , M. Heydari 3
1 - Former MSc. Student of Agronomy, Sabzevar Branch, Islamic Azad University, Sabzevar, Iran
2 - Assistant Professor, Department of Agronomy, Sabzevar Branch, Islamic Azad University, Sabzevar, Iran
3 - Associate Professor, Industrial University of Shahrood, Shahrood, Iran
Keywords: nitrogen, competition, Wheat, weed, Herbicides,
Abstract :
In this study, the effect of split application of nitrogen and herbicide doses on the yield and yield components of wheat as infested with weeds were evaluated at the Research Field of Motahari Agricultural School of Sabsevar, Iran. The experiment was conducted in split plot with three replications. The three split applications of 150 kg.ha-1 of nitrogen as urea [30% at planting and 70% at stem elongation (T1), 25% at planting, 25% at tillering and 50% at stem elongation (T2), 25% at planting, 50% at tillering and 25% at stem elongation (T3)] were assigned to main plots, and five doses of herbicide applications (0, 25, 50, 75 and 100 % of recommended dosage of Imazamethabenz-methyl) to sub- plots. The results showed that herbicide doses significantly affected yield and yield components of wheat and weed population. Increasing of herbicide doses affected biological and grain yield of wheat positively. The results also indicated effect of nitrogen application methods were more pronounced than that of herbicide doses. The highest spike per m2, thousand grain weight, biologic and grain yield, as well as the least number of infertile spikelet, were obtained by T3 treatment of nitrogen fertilization and herbicide application at recommended doses. These results suggested that 75% recommended dosage of Imazamethabenz-methyl and application of nitrogen by using T3 treatment would increase, economic yield of wheat.
