AMELIORATIVE EFFECTS OF ABSCISIC ACID AND YEAST ON MORPHO-PHYSIOLOGICAL AND YIELD CHARACTERISTICS OF MAIZE PLANT (Zea mays L.) UNDER WATER DEFICIT CONDITIONS

A field experiments were conducted at the research farm of the Faculty of Agriculture, Kafrelsheikh University, Egypt, during two successive seasons, to evaluate the influence of abscisic acid (250 ppm) and yeast (4g l(-1)) application on morho-physiological and yield traits of maize under water deficit conditions. Water deficit led to significant decreases in number of leaves, chlorophyll concentrations and grain yield compared to control, while electrolyte leakage (EL) rate and lipid peroxidation (MDA) significantly increased. Additionally, significant reduction in antioxidant enzymes activity, protein and oil percentages were recorded in maize plants under water deficit conditions. Application of ABA at 250 ppm and yeast at 4 g l(-1) individually or companied led to significant increases in number of leaves, leaf area, chlorophyll concentration, relative water content and antioxidant enzymes activity in the stressed plants compared with control plants. Moreover, 1000-grain weight, grain yield, protein, oil and moisture percentages significantly increased in stressed treated plants, whereas EL and MDA were significantly decreased. Thus, it could be recommended that application of ABA at 250 ppm and yeast at 4 led to decrease the harmful effects of drought and enhance growth characteristics, antioxidant enzymes activity and as well as grain yield in maize crop.