Biochemical and Physiological Response of Egyptian Wheat Genotypes to Drought Stress

Drought one of the imperative abiotic stresses which limits plant growth and causes numerous biochemical physiological and morphological changes in Wheat. In this study, ten Egyptian spring wheat genotypes used were obtained in cooperation with the Egyptian Gene Bank at the Agricultural Research Center. The greenhouse growth model was applied to test the morphological and physiological traits of the ten wheat genotypes in a Randomized Complete Block Design (RCBD) with three replications. The biochemical and physiological properties, total phenols, peroxidase enzyme, proline, total protein concentration, chlorophyll concentration and nutritional elements: (Ca+2, Mg+2, k+, Na+), and total sugars were studied. The morphological traits were the plant height, flag leaf area, dry weight, fresh weight, thousand grain weight and grain yield. Results showed highly significant differences among genotypes for the measured traits under normal and drought stress. Increase in total phenols, free proline, total protein and K+ uptake under drought. The results were classified the ten wheat genotypes in three groups, tolerant, moderate, and sensitive to drought stress. Each genotype has a feature of drought tolerance by containing certain characteristics. Genotypes L7 and L10 has genetic makeup that has more than one trait that indicates that it is drought to tolerant, while L4, L6 and L9 were moderate tolerant to the stress. The L1 and L3 were the most sensitive genotypes to drought stress. The correlation between the biochemical and physiological traits were studied and the results show significant positive correlation between Na+ with total protein and Ca+2 under drought stress. However, there are high and significant correlations between total phenols with free proline under control and drought conditions.