Effect of Foliar Application of Iron and Zinc Sulphate on Yield and some Physiological Characteristics of Camelina (Camelina sativa L. crantz) in Rainfed Conditions

Lack of moisture and calcareous of agricultural soils are the main factors reducing the efficiency of absorption of micronutrients such as iron and zinc from soil solution and reducing the yield of crops in most rainfed areas. Therefore, in order to evaluate the effect of foliar application of different concentrations of ferrous and zinc sulphate in rainfed conditions on grain yield and some physiological characteristics of Camelina, the present research was conducted as a factorial experiment in a randomized complete blocks design with three replications in Kermanshah during the cropping year 2017-2018. Experimental treatments include foliar application of micronutrients at five levels (no foliar application and foliar application of iron sulphate and zinc at concentrations of 4 and 8 per thousand) and the factor of foliar application time at two levels at the beginning of vegetative growth and the time of Camelina flowering. Based on the obtained results, using foliar application treatments significantly increased the grain yield compared to the control treatment. The highest increase in grain and oil yield was related to the foliar application treatment of zinc at 8 per thousand level and at flowering time, which increased these traits from 1099 and 399 in control conditions to 1580 and 663 kilogram per hectare, respectively. Foliar application treatments and their application time caused a significant increase in other agronomic traits such as biomass yield, harvest index, number of pods per plant, number of seeds per pod, one thousand-seed weight, oil percentage and also physiological traits include concentrations of chlorophyll a and b, soluble sugars, proline and activity rate of superoxide dismutase antioxidant enzymes, peroxidase and catalase of leaves. But they had no significant effect on the content of carotenoids and total phenol. The highest additive effect on the investigated physiological treatment was related to the application of zinc sulphate at 4 per thousand levels at the beginning of generative growth, which increased the activity of antioxidant enzymes and catalase and superoxide dismutase by 85 percent on average.