Reaction of morphologically and yield of sunflower to zinc sulfate and irrigation intervals

In order to find out the effect of different levels of zinc sulfate and irrigation intervals on morphological characteristic and also on yield and yield components of sunflower. Plot in a completely randomized blocks including three replications different levels of irrigation namely 10, 20 and 30 days as first factor and zinc sulfate levels of 0, 20 and 40 kg per hectare the second factor. Irrigation was in main plot and zinc sulfate in subplots. Measurements included; leaf area index at start of blooming, final leaf area index, leaf weight of stem, weight of over ground parts, special density of leaf, ratio of leaf weight to stem of plant, diameter of stalk, number of days till reproductive stage, number of days till full bloom, number of days till end of pollination, time between blooming and complete physiological ripening of seeds, length of reproductive period, flower diameter, number of seeds per flower, weight of 1000 seeds, dry weight of seed per flower, ratio of weight of seed per flower to weight of flower, percent of unfertilized seeds, seed yield and the yield index. Statistical analysis was preformed by analysis of variance and Duncan method. The results showed that by increasing the interval of irrigation decreases the yield and on the most of under research components had bad effects; zinc sulfate deficiency has effect on most of characters there was no significant difference between 20 and 40 kg zinc sulfate per hectare. The interaction between irrigation and zinc sulfate consumption indicates that between 10 and 20 days irrigation yield is differed significantly. Other measured characters also got better in the presence of zinc. Even the application of zinc at 20 days irrigation interval resulted the yield equal to 10 days interval. In 30 days irrigation period zinc sulfate has no effect on yield and some other characters; but caused the number of seeds per flower and increase of vegetative growth of sunflower. The height yield was detected in 10 days irrigation interval and 40 kg of zinc sulfate application per hectare as 3258 kg per hectare. In irrigation interval of 20 days and use of 40 kg zinc sulfate caused the yield from 2433 kg (no zinc sulfate) to increase 2881 kg per hectare.