Phenol Content Assays and Corn Grain Yield by Zinc and Iron Consumption in Cut-off Irrigation Conditions

This experiment was conducted to evaluate the effect of micronutrients on leaf phenol content and yield of SC704 corn hybrid in water deficit condition during two years (2018-2019 and 2019-2020) in Shahid Salemi farm of Ahvaz. The experiment was conducted as split-split plots in a randomized complete block design with three replications. Main plots included water deficit stress at three levels (complete irrigation, cut-off irrigation at vegetative growth stage (12-14 leaf stage), and cut-off irrigation at early seed growth stage (13-15 days after pollination), and sub-plots included sulfate foliar application zinc sulfate at three concentrations (0, 5, and 10 g/L) and sub-subplots contained foliar solution of iron sulfate at three concentrations (0, 3, and 6 g/L). The results of this study showed that foliar application of zinc sulfate in the cut-off irrigation conditions in the vegetative growth stage and in the beginning of the seed growth stage led to a significant increase in stomatal conductivity and leaf phenol content. The lowest leaf proline was obtained under complete irrigation conditions without iron sulfate solution. The highest yield of ear was obtained in complete irrigation with 6 g/L concentration of FeSO4 (9135.66 kg/ha), which increased by 25.1% compared to non-spray at this irrigation level. In general, unfavorable changes in physiological and functional indices of SC704 corn hybrid under the cut-off irrigation at the reproductive growth stage were more than the vegetative growth stage, and the application of zinc sulfate and iron sulfate in optimal concentration led to reduce the damage and adverse effects of water stress in these growth stages.