Foliar Fertilization of Zinc, Iron and Manganese in Safflower (Carthamus tinctorius L.) under Rainfed Conditions

Safflower (Carthamus tinctorius L.) is an important oilseed crop cultivated in semi-arid regions, where micronutrient deficiencies, especially zinc, iron, and manganese, often limit its growth and yield. For investigating the effects of foliar fertilization of zinc, iron and manganese in safflower under rainfed conditions, this project was conducted in Ilam. The studied soil had low concentrations of available zinc, iron, and manganese, measured at ۰.۶۱, ۴.۱۵, and ۴.۱۳ mg kg-۱, respectively. The research was conducted with the following treatments: ۱- control, ۲- water spray ۳- foliar spraying with zinc sulfate ۴- foliar spraying with manganese sulfate ۵- foliar spraying with iron sulfate ۶- foliar spraying with zinc and manganese ۷- foliar spraying with zinc and iron ۸- foliar spraying with iron and manganese ۹- foliar spraying with zinc, iron and manganese in a randomized complete block design with three replications. The results showed that the simultaneous foliar spray with zinc, iron and manganese, with a yield of ۱۱۱۲ kg ha-۱ was in the superior statistical group and the increase in yield compared to the control, and water spraying treatments was ۱۳.۴ and ۱۲.۵ percent, respectively. Regarding oil yield, it was also found that the combined foliar spraying of zinc, iron and manganese and combined foliar spraying of zinc-manganese were in the superior statistical group with ۳۹۷ and ۳۸۱ kg ha-۱, respectively. The increasing effect of foliar spraying on the concentration of zinc and iron in the grain was ۲۴ and ۱۹ percent, respectively, compared to the control. Also, the highest photosynthesis rate, SPAD and stomatal conductance were observed with the application of Zn + Fe + Mn compared to the other treatments. In general, the best results for grain yield, oil yield, improvement of nutrient concentration and photosynthesis rate were obtained with combined foliar spraying of zinc, iron and manganese and zinc-iron foliar spraying, respectively.

کلیدواژه ها:

Ilam ، Micronutrients ، Nutrient concentration ، Photosynthesis rate