Pumpkin is an important annual medicinal plant. The grains of pumpkin contain medicinal raw materials that are used for producing pharmaceutical products such as peponen, pepostrin and gronfing to overcome prostatic hypertrophy and urinary tract irritation. Pumpkin oil is rich in unsaturated fatty acids. So, present experiment in order to evaluate the effect of different irrigation intervals on the yield and fatty acids of pumpkin, was conducted at the Research Farm of Bu-Ali Sina University using randomized complete block design with four treatments (6, 9, 12 and 15 days) and three replications. Effect of treatments on all traits was significant. Means comparison showed that the highest linoleic fatty acid (40.10%), oleic fatty acid (37.18%) and grain yield (84.84 g m-2) was obtained at 6 days irrigation interval with had no significant difference with treatment of 9 days irrigation interval. Also, in comparison with 6 days irrigation interval the lowest values for these traits with reduction of 6.60, 5.64 and 55.23% were revealed at 15 days irrigation interval. Therefore, it seems that the treatment of 9 days irrigation interval is suitable for production the highest seed and fatty acids of pumpkin.
