This study was carried out in the experiments field of college of Agriculture / Diyala University – Iraq during the planting season 2015 – 2016, Using the split – split plot design in the experiment, and arranging randomized complete block design (RCBD), In three replications. Experimental treatments include: adding water after draining 25% (W1) ,50% (W2) and 75% (W3) of available water, and add potassium concentration of 5000 (K1),5500 (K2) and 6000 (K3) mg.L–1 as potassium sulfate (K 41% ), and spraying abscisic acid (ABA) at concentration of 0.0 (ABA0), 10.0 (ABA1) and 20.0 (ABA2) mg. L–1. The results showed: The third potassium level K3 excellence on the levels K1 of proline , chlorophyll , percentage of malic acid and the concentration of potassium in plant leaves increased in values 46.36%, 21.01%, 34.45%, 17.5% respectively under different moisture levels. The results showed that third level of abscisic acid sprayed ABA2 increase the proline acid and abscisic acid concentration as compared with the both of control (ABA0) and the second ( ABA1) .The concentration of proline in leaves significant increase of 69.0% by interaction between(K3 + ABA2) compared with (K1+ABA0) .The concentration of Abscisic acid in leaves was not affected by increasing potassium although the concentration of Abscisic acid has doubled with a decrease moisture content of the soil. Increasing the potassium spraying K3 leads to reduce the negative impact of low level of moisture W3 on the concentration of proline, chlorophyll, percentage of malic acid and the potassium concentration in the leaves with a percentage 30.65%, 26.92% , 48.78% ,15.18% respectively. Also the most of characters were significantly influenced by interaction between potassium and Abscisic acid concentrations under moisture tension.
Keywords: Abscisic Acid, Malic Acid, Moisture Tension, Potassium
