Effect of Foliar Application of Nutrients and Growth Regulators on Yield of Wheat Under Water Stress (with Removing The Last Stage of Irrigation) at the end of the Growing Season

Usingplant growth regulators and some nutrients is one of the agronomic strategies to increase the tolerance of plants to water stress. Therefore, according to the recent droughts in the country, where farmers cannot provide the necessary water for the last stage of irrigation in wheat fields in the Ajab-Shir region, it seems that their application can be used to prevent yield loss of Wheat. The aim of this study was to evaluate the effect of seven treatments on Pishgam wheat including pure water (equivalent to the solution used in other treatments as control, salicylic acid (100 mg L-1), folic acid (50 µM), potassium chloride 3%, zinc sulfate 4 per thousand, urea 4%, abscisic acid (2 mg L-1) in flooding irrigation condition (planting and flag leaf emergence stages). Expriment was desighned as a randomized complete block at the occurrence of water stress in the end of the plant growing season. The results showed that treatments could improve the moisture relationship and the photosynthetic pigments of wheat leaves under water stress conditions. Foliar application of urea, salicylic acid and folic acid also increased grain yield by 2704 (42%), 2054 (32%), and 1962 (31%) kg. ha-1, respectively. This increase is due to the increase in the number of fertile tillers and the decrease in the number of infertile tillers per plant, this led to a significant increase in the share of photosynthetic material transferred to the seed (harvest index). According to the findings of this study, salicylic acid, folic acid and urea can be used to reduce the adverse effects of moisture stress on the wheat.