بررسي اثرات دور آبياري و كود نيتروژن بر عملكرد دانه برنج

The effect of irrigation interval and nitrogen fertilizer on rice

Rice production in Iran needs to increase to feed a growing population whereas water for irrigation is getting scarce. One way to decrease of water consumption in paddy field is change of irrigation regime and replacement of continuous submergence (CS) to alternately submergence (AS). On the other hand one way to increase the yield in hectare of rice is utilization of fertilizers specially nitrogen fertilizer. In order to investigating the effect of different regimes of irrigation and nitrogen fertilizer on yield of hybrid rice an experiment was conducted at rice research institute of Iran during crop season 2008. An experiment was arranged in split plot based on completely randomized block design with 3 replications in which water regimes were main factor included continuous submergence and alternative submergence conditions (irrigation intervals of 5, 8 and 11days) and nitrogen fertilizer levels were sub factor included 0, 90, 120 and 150 kg/ha. Biomass, yield and yield components were statistically the same under CS and interval irrigation of 5 and 8 days. Irrigation water input in 8 days interval was 18% less than continuous submergence. Grain yield was 7418 kg/ha with 120 kg N/ha.in yield components, number of seed in panicle and 1000 grain weight had maximum effect on increase of grain yield.