عنوان مقاله [English]
نویسندگان [English]چکیده [English]
The aim of this research was to evaluate the effects of irrigation interval and nitrogen fertilizer on phenology, yield and seed quality of pumpkin. Experiment was laid out as a split plat based on randomized complete block design with three replications at the Bu-Ali Sina University in growing season of 2013. The main plots included irrigation intervals at four levels of I1: 6 days irrigation interval, I2: 9 days irrigation interval, I3: 12 days irrigation interval, and I4: 15 days irrigation interval and sub plots included different nitrogen levels of N0: 0 kg N/ha, N1: 60 kg N/ha, N2: 120 kg N/ha, N3: 180 kg N/ha,N4: 240 kg N/ha from the source of urea fertilizer. In the present research traits of days to flowering, days to fruiting days to maturity, seed number/fruit, 100-seed weight, grain yield, oil percent and oil yield were evaluated. The effect of irrigation interval and nitrogen on all traits was significant. Effect of treatments interaction was also significant on all traits except number of seeds/fruit and oil yield. The highest values for days to flowering and days to maturity were achieved at I2N3 treatment. Also, maximum and minimum values for 100-seed weight as well as grain yield were achieved at I2N3 and I4N0 treatments, respectively. I2N3 had no significant difference with treatments of I1N3، I1N4 and I2N4. In comparison with I2N3 treatment, the lowest values for days to flowering, 100-seed weight and grain yield with reduction of 35, 68 and 73%, respectively, were revealed at I4N0 treatment. The highest percent (46.81) and oil yield (32.90 g/m2) with no difference with I2 treatment, revealed at I1 treatment. In comparison with I2 treatment, I4 treatment reduced 52.50% oil yield. Also, the highest oil yield (27.50 g/m2) was achieved at N3 treatment. Therefore, in order to optimizing water and nitrogen consumption in pumpkin production, I1N3 treatment was identified suitable treatment.