Investigation of the Role of Potassium Sulfate Solution Containing Zinc Chelate in Increasing Yield and Decreasing Water Consumption in Wheat in Kahnooj Region (Kerman)

In order to investigate the role of potassium and zinc fertilizers in increasing yield and reducing water consumption of wheat (Triticum aestivum L.), a field experiment was conducted in the form of a randomized complete block design with five treatments and three replications in November 2017 in Kahnooj city in Kerman province. Experimental treatments in this study include; the first treatment: control (consumption of all fertilizers except potassium based on the results of soil analysis with 7 irrigations); The second treatment: the conventionl fertilizing by the local farmers (NP) with 7 irrigations; Third treatment: first treatment + application of potassium sulfate (SOP) before planting, with 7 irrigations; Fourth treatment: first treatment + application of 33% sulfate-potassium (SOP) before planting and 67% of the remaining source of soluble potassium sulfate (SSOP) as foliar application with 7 irrigations; Fifth treatment: The first treatment + application of 33% of sulfate-potassium (SOP) before planting and 67% of the remaining source of sulfate-potassium solution containing chelate (SSOP + Zn-EDTA) as foliar application and irrigation in 5 times. The results showed that A) application of potassium and zinc fertilizers had a significant effect on yield, protein content, phosphorus, potassium and zinc concentrations and also, molar ratio of phytic acid to zinc (unfavorable nutritional index) Zn) in grain as well as water and potassium use efficiency. B) While the yield and percentage of protein in the grain in the control treatment was 4648 kg/ha and 11.68%, respectively, in the second, third, fourth and fifth treatments were 4077 and 8.57, 5402 and 69, 12.12, 6137 and 13.62, increased 6022 kg/ha and 13.85%, respectively. C) Unfavorable nutritional index (molar ratio of phytic acid to zinc) - (PA/Zn) in wheat grain in the control treatment was 46, while this ratio in the second, third, fourth and fifth treatments were 74, 33, 23, respectively. D) While the water use efficiency in the control was equal to 0.62 kg/m3, the values in the second, third, fourth and fifth treatments were 0.54, 0.72, 0.82 and 1.11 kg/m3, respectively. The efficiency of potassium fertilizer in the third treatment was 2.51 kg/kg, in the fourth treatment this value improved to 4.96 and in the fifth treatment to 4.58 kg/kg. E) Despite the reduction of water consumption from 7560 cubic meters in all four treatments to 5400 cubic meters in the fifth treatment, the yield in the fifth treatment compared to the control treatment had a 31% increase in yield, which was significant at the a percent probability level. Considering the above results, it is concluded that in soils where the concentration of potassium and zinc is less than the critical limit, it is better to use potassium and zinc fertilizers in several stages.