Investigation of the effects of different irrigation water and nitrogen regimes on cotton yield and yield component under furrow and sprinkler irrigation methods

Irrigation water and nitrogen fertilizer are two important factors in increasing the yield and yield components of cotton. In order to evaluate effects of irrigation methods, various levels of water and nitrogen fertilizer on yield and yield components of cotton were studied at Hashemabad Cotton Research Station of Gorgan in 2008. The experiment was conducted in split-split plots design with three replications. Furrow and Sprinkler methods were main plots, various levels of irrigation water 0%, 33%, 66%, 100% and 133% of water requirement were subplots plots and various levels of nitrogen fertilizer 0%, 33%, 66%, 100% and 133% of recommended fertilization were sub-sub. The results showed that the effect of irrigation methods were significant on boll weight, seed index, number of seed per boll and lint index but without significant on yield and lint yield. The yield were influenced by various levels of irrigation water and the results showed that the highest yield 1996/60 was obtained in treatment 66% of irrigation water. Levels of irrigation water significantly affected on the entire yield components of cotton except the number of seed per boll. It was also found that the effect of various levels of nitrogen fertilizer showed significant difference on yield, boll and lint yield. The results revealed that yield and lint yield didn’t have significant difference between treatments 133% and 33%, 66%, 100% of various levels of nitrogen fertilizer.