Response of Bread Wheat to Abscisic Acid Under Water Stress


Abstract-Field experiments were carried out at the Field Crops Research Stationof the Agricultural Research Office - Abu Ghraib, during Seasons of 2014-2015and 2015-2016 to study the effect of four concentrations of abscisic acid (ABA)on some of the physiological characteristics of cultivar bread wheat (Bohooth10)under water stress. The experiments were applied according to randomizedcomplete block design (RCBD) by split plot arrangement with three replicates.Water treatments, which occupied the main plots, included four water irrigationquantities, which were irrigated when depletion 50%, 70% and 40% of availablewater, in addition to rainy treatment (germination irrigation + rainfed), whileABA seeds soaking concentration, which occupied the sub-plots, were 0, 0.25,0.50 and 0.75 mg/Lt. The results showed superiority of 50% and 70% treatmentsin the grain yield character which gave 4.65, 4.82, 4.61 and 4.87 ton/ha for bothseasons respectively, while rainy treatment has given higher of proline (5.13 and7.39) micromole/g and peroxidase (45.77 and 49.14) absorption unit/g for bothseasons respectively. Increasing of ABA concentration up to 0.75 mg/Lt lead toraise the relative water content (77.41 and 77.62%), ratio of soluble sugars (15.29and 15.35)% and grain yield (3.61 and 3.92) ton/ha for both seasons respectively.We can conclude that there was a significant response for ABA concentrationsunder water stress to improve growth and yield wheat