Investigation of irrigation interval and nitrogen rates on some growth indices and yield of corn

In order to investigate the effects of irrigation and nitrogen application on some morphological traits and grain yield of corn (SC704) an experiment was conducted in agricultural research farm of Lahijan during 2010. Experimental design was split plot based on Randomized Complete Blocks Design in three replications. Main plots were three irrigation regimes including (rainfed, irrigation interval after 6 and 12 days). Sub plots were five nitrogen rates (0, 60, 120, 180 and 240 kg N ha-1). The results indicated no irrigation and nitrogen application caused significant reduction in leaf area index, total dry matter and grain yield. Non significant differences exist between 180 and 240 kg N ha-1 treatments and also 6 and 12 days irrigation interval in above traits. With reduction of irrigation water and nitrogen rates, silking and ear formation delayed and flowering duration decreased. In general, the most appropriate management of irrigation and nitrogen obtain in irrigation interval after 12 days and 180 kg N-1 treatments.