Effects of nitrogen and zinc spray on yield of corn (Zea mays L.) in drought stress

Abstract

In hot and arid regions, drought stress is considered as one of the main reasons for yield reduction. To study the effect of drought stress, nitrogen and zinc spray on the yield and yield components of corn, an experiment was carried out during the crop seasons of 2010 and 2011 on Emam Khomeyni research Farm in Mahvellat as a split factorial within randomized complete block design with three replicates. The main plots with irrigation factor and three levels were considered: full irrigation, stopping irrigation at anthesis step and stopping irrigation at the seed filling stage. Subplots were considered with and without nitrogen and zinc spray. The drought stress reduced the grain yield in anthesis stage more than other stages. Drought stress effects significantly on stem and ear diameter, ear length, chlorophyll value, leaf area index, leaf relative water content, stem, ear and leaves dry weight, number grain in ear and row, number row in ear, unfilled seed percentage and thousand grains weight. Nitrogen increased the seed yield and yield component except thousand grains weight and the number of row in ear. Using Zn, as compared with control treatment, causes the increase of grain yield, thousand grains weight and number grain in ear 16.5, 9 and 5.5%, respectively. The results obtained from the present research showed that anthesis stage was most sensitive stage to drought stress. Also nitrogen and Zn could somewhat reduce the impact drought stress on corn.