EFFECT OF POST ANTHESIS DROUGHT ON CERTAIN AGRONOMICAL CHARACTERISTICS OF WHEAT UNDER TWO DIFFERENT NITROGEN APPLICATION CONDITIONS

Abstract

A field experiment was conducted to evaluate effect of drought stress at the post anthesis stage on a bread wheat cultivar, Gönen, during the 2009-10 and 2010-11 growing seasons. Plants were covered with a rainout shelter after the post anthesis stage to prevent rain. Nitrogen fertilizers were applied at two different ways during the plant growth. The experiment was arranged in split block with three replications. Grain yield was 2445 kg/ha under the control condition whereas 1755 kg/ha under the drought condition. High amount of early application of nitrogen fertilizer resulted in 21.6 % increase in grain yield. Drought after flowering stage caused 5.2 % and 20.7 % reduction in thousand kernel weight and kernel number respectively. But there were no significant effects of nitrogen treatments on these traits. Plant height, tiller number, spike number, spikelet and kernel number, single plant yield, spike and stem weight decreased as a result of drought stress after post anthesis while only tiller number and spike number interacted with nitrogen treatments under the stress condition. The results suggested that early application of nitrogen leads to sufficient plant growth and root development resulting in a better adaptation to the post anthesis drought conditions.