سید بصیر موسوی - دانشجوی دکتری، گروه زراعت، واحد تاکستان، دانشگاه آزاد اسلامی، تاکستان، ایران.
سعید سیف زاده - دانشیار، گروه زراعت، واحد تاکستان، دانشگاه آزاد اسلامی، تاکستان، ایران.
حمید جباری - استادیار، موسسه تحقیقات اصلاح و تهیه نهال و بذر، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران.
علیرضا ولدآبادی - دانشیار، گروه زراعت، واحد تاکستان، دانشگاه آزاد اسلامی، تاکستان، ایران.
اسماعیل حدیدی ماسوله - استادیار، گروه زراعت، واحد تاکستان، دانشگاه آزاد اسلامی، تاکستان، ایران.

The current study tries to evaluate the effect of auxin foliar application in two safflower cultivars under drought stress condition, using a factorial split plot experiment with randomized complete block design in two years (۲۰۱۷-۲۰۱۸ and ۲۰۱۸-۲۰۱۹). It has been conducted at research field of Seed and Plant Improvement Research Institute in Karaj and evaluates irrigation at two levels including normal irrigation (control) and interruption of irrigation from the beginning of grain filling stage (drought) in the main plots and cultivars of Padideh and Goldasht and auxin foliar application in two levels of non-foliar application of distilled water (control) and foliar application of auxin (indole acetic acid) in one step (mid-flowering) at a concentration of ۳۰۰۰ mg.l-۱ (۳۰ ppm) in sub-plots as a factorial. In the auxin foliar application and non-foliar application (control) in both normal irrigation and drought stress treatments, the highest total number of heads per plant in Goldasht cultivar have been ۲۶.۳ and ۲۴.۳ respectively, and the highest grain number per plant observed in Goldasht cultivar have been at ۷۰۸ and ۵۹۲, respectively. Auxin foliar application and irrigation has had no significant effect on the grain oil percentage. Goldasht cultivar demonstrates a higher grain yield compared to Padideh cultivar due to lower head temperature, higher soluble carbohydrate concentration, number of heads, and ۱۰۰۰-grain weight. Generally, results show that the effect of the studied treatments is affected by the year and despite the positive effect of auxin foliar application on some yield components at both irrigation levels, foliar application of auxin at middle of flowering stage has no significant effect on grain yield.

دمای طبق, شاخص سطح برگ, عملکرد دانه, قطع آبیاری, وزن هزار دانه