Aba Sensitivity as a Criterion for Drought Tolerance in Wheat (Triticum Aestivum L.) Cultivars

Abstract

Criteria used for evaluating drought tolerance of wheat cultivars demanding more time and efforts are usually not efficient and conclusive. Present study was conducted to evaluate ABA sensitivity as a criterion for evaluating drought tolerance of wheat cultivars at an early stage. Ten cultivars of wheat were subjected to drought at 3-leaf stage to select the most sensitive and two tolerant cultivars using mortality rate. Tatara was found the most susceptible whereas GA-2002 and Chakwal-50 were the cultivars with maximum drought tolerance. These cultivars were used to study sensitivity to applied absicic acid (based on germination index and relative growth inhibition rate) and physiological responses (leaf water content, chlorophyll stability index, coefficient of relative inhibition and proline accumulation) under drought stress. Highest ABAsensitivity was recorded in GA-2002 and Chakwal-50 whereas Tatara manifested minimum sensitivity. ABAsensitivity corresponded to physiological indices of drought tolerance. Results show that ABA-sensitivity is an efficient criterion that can be used to evaluate drought tolerance of wheat cultivars at early stage