ABSCISIC ACID AND SALICYLIC ACID SEED TREATMENT AS POTENT INDUCER OF DROUGHT TOLERANCE IN WHEAT (TRITICUM AESTIVUM L.)

Two experiments were conducted to study the abscisic (ABA) acid and salicylic acid (SA) seed soaking induced regulatory role on protein content, soluble sugars, membrane stability index (MSI) and protein profiling through SDS-PAGE in two wheat varieties viz., Wafaq-2001 and Punjab-96. In the pot study significant interaction between treatments and cultivars for soluble protein content was observed where drought stress and Drought + ABA caused increase in soluble proteins in cv. Wafaq-2001. There occurred decrease in MSI (%) in Punjab-96 whereas the effects of ABA and SA were at par to increase the MSI (%). The soluble sugar contents significantly increased under drought stress. Drought + ABA and Drought + SA caused 29% and 37% increase in soluble sugars of Wafaq-2001 respectively. Protein profiling through SDS-PAGE revealed the presence of polypeptides of 18, 25 and 38 kDa under drought and control in both the cultivars. ABA seed treatment induced a new protein of 18 kDa in cv. Punjab-96. Similarly; SA treatment induced a new protein of 45 kDa in the same cultivar under drought stress. The beneficial effects of ABA and SA pre-soaking were also reflected in the form of increased grain yield. Results of the current research investigation provide new insights that can lead to a better understanding of the molecular basis of drought-sensitivity in wheat and its possible mitigation by ABA and SA seed treatments. Therefore, the current findings could be used by plant breeders to develop drought resistant as well as ABA and SA responsive wheat cultivars, in order to improve the wheat yield in the dry areas.