مطالعه اجزای عملکرد، عملکرد دانه و کارایی مصرف نیتروژن در زراعت کدوی پوست کاغذی

In order to managing of nitrogen in the cultivation of pumpkin, an experiment was conducted at the Research Farm of Bu-Ali Sina University using randomized complete block design with five treatments (0, 60, 120, 180 and 240 Kg N h-1) and three replications. Based on results, effect of experimental treatments on all traits except number of seed per fruit was significant. Mean comparison of the nitrogen levels showed that the highest number of fruits per plant and seed yield belonged to 180 Kg N which had no significant difference with level of 240 Kg N. The lowest values for these traits with reduction of 20.72 and 36.82% in comparison with 180 Kg N, respectively, were revealed at control treatment (non used fertilizer). Also, the highest and the lowest values of 1000-seed weight were achieved at 180 Kg N and control treatments, respectively. Maximum nitrogen use efficiency was revealed at 180 Kg N treatment. The lowest value of this trait with reduction of 38.09% was obtained from treatment of 240 Kg N. therefore, consumption of 180 kg N ha-1 produced maximum grain yield and improved nitrogen use efficiency.