عنوان مقاله [English]
In 2012 a factorial experiment was conducted in Khodabandeh Dryland Research Station to study the effects of foliar spraying of urea, potassium chloride and urea + potassium chloride on grain yield, grain protein and leaf relative water content of Sardari wheat under rainfed condition. Also, to determine the most effective application time of nutrients used at various growth stages including double ridge, milky and double stage + milky stage, factorial experiment had 15 treatments and arranged in a randomized block design with three replications. The amounts of urea and potassium chloride used as foliar spraying were equivalent to 20 kg/ha. The urea and potassium chloride were sprayed with concentrations of 5 and 1%, respectively. Growth preserved leaf moisture and resulted in highest leaf relative water content. Spraying potassium chloride + urea in double ridge and milky stages resulted in highest grain yield, biological yield, thousand kernel weight, number of kernel per head and grain protein content. These parameters showed 40, 9.3, 49 and 7.9% increasing comparing to the check, respectively. The overall results showed that spraying potassium chloride before anthesis stage increased grain yield and number of grain per head, while spraying after anthasis stage increased significantly protein content and thousand kernel weight.