Effect of drought-induced stress by PEG6000 on physiological and morphological traits of chickpea (Cicer arietinum L.) seed germination in order to assortment of drought tolerant cultivars

In this study, the reaction of germination and plantlet growth different chickpea cultivars (Arman, Azad, Binalood and Hashem) in relation to osmotic stress due to polyethylene glycol solution (-2, -4, -6 and -8bar) and control (distilled water) using factorial design in completely randomized with four replications was evaluated. In this study, there was a significant difference between the different potentials of drought stress for all measured traits with 99% probability. With the reduction of water potential, the seed germination, germination rate, rootlet length, stemlet length, rootlet wet weight, rootlet dry weight, stemlet wet weight, stemlet dry weight, plantlet wet weight, as well as plantlet dry weight decreased. Also, proline and Fv/Fm (the efficiency quantum of the photosystem II) of cultivars at two levels of control and glycol polyethylene solution at the level of -2bar was different. So that the Hashem cultivar showed the highest amount of proline in the polyethylene glycol solution -2bar. However, the Fv/Fm had a reversed relationship with drought stress. That is, drought stress leads to a reduction in the Fv/Fm. The maximum amount of Fv/Fm was found in the Hashem cultivar under drought stress condition, and the lowest amount in Azad cultivar in stress conditions. The results of activity of antioxidant enzymes in this study showed that drought-resistant cultivars such as Hashem is  to drought stress by increasing the capacity of the antioxidant system to remove reactive oxygen species and prevent membrane peroxidation Overall, the commercial cultivar Hashem showed drought tolerance at high stress levels, indicating their potential for production applications.