Evaluation of the Efficiency of Foliar Potassium Applications as Drought Mitigation

Abstract

A FIELD experiment was performed to investigate the mitigation effects of foliar K on wheat under drought stress. Foliar potassium treatments, either in terms of sources and concentrations, relatively increased wheat water use by about 111 and 117 and 114 % for the foliar application of K2O-K2SO4 and 120, 120 and 117% for the foliar application of K2O-K2SiO at concentration treatments of 0.5, 1.0, and 2% respectively relative to control treatment (0.0 KO) = 100. The positive mitigation effects of K on wheat water use were more pronounced for using K2 respectively. The foliar application of potassium either in the forms of K2SO at the different tested concentrations increased the grain production per unit of water use. Where water use efficiency reached about 2.23, 2.34 and 2.27 kg/m3 for K2SO4432SiO or K3 than K2SiO and 2.41, 2.39 and 2.33 kg/m for K2SiO3 at concentrations of 0.5, 1 and 2% K2O respectively compared to 1.99 kg/m for the control treatment. It could be concluded that the foliar K application may act positively act to mitigate drought stress particularly when applied at the beginning of the emergence, tillering and flowering stages of wheat.