COMBINED APPLICATION OF GLYCINEBETAINE AND POTASSIUM ON THE NUTRIENT UPTAKE PERFORMANCE OF WHEAT UNDER DROUGHT STRESS

摘要

Global warming is posing threat to agriculture through increasing incidence of abiotic stresses particularly drought stress. Water stress at grain filling stage of wheat crop is detrimental to crop mineral nutrition because it reduces soil moisture and inhibits the optimal crop growth and development by decreasing the availability of nutrients uptake. Glycine betaine and potassium production is accelerated in plants particularly under drought stress conditions for regulation of cell homeostasis (protective mechanism). For the reason, a pot and two field trials were conducted to evaluate the impact of foliar application of glycine betaine and potassium alone and in combination, when water was withheld at grain filling stage. Different doses of glycine betaine (0, 50, 100 and 150 mM) and potassium (0, 0.5, 1.0 and 1.5%) and all possible combinations were used. After harvesting, plant mineral content (N, P, K, Na, and Ca) was assessed. The results indicated that the application of K at 1.5% in combination with glycine betaine at 100 mM was most beneficial in diluting the impact of water stress at grain filling stage. Further it was suggested that the responses of wheat crop to these osmolytes should be studies at molecular level under drought to identify the mechanisms which are tangled for variable plant responses.