Role of Jasmonic Acid and Abscisic Acid Treatments in Alleviating the Adverse Effects of Drought Stress and Regulating Trypsin Inhibitor Production in Soybean Plant.

Jasmonic acid and abscisic acid are important intracellular regulators mediating diverse developmental processes, such as seed germination, leaf abscission and senescence. In addition, they are essential mediators in triggering some plant responses to abiotic stresses including drought, salinity and cold. How hormones interact to coordinate these responses which are referred to as signalling crosstalk is an area receives intense interest from plant physiologists. The aim of the present work is to study the possible roles of treatments with jasmonic acid (100μM), abscisic acid (100 μM) and their combination (100 μM JA + 100 μM ABA) on alleviating the harmful effects of drought stress on endogenous phytohormones, polyamines, total soluble protein and protein banding pattern of soybean plant (Glycine max L cv. Giza 22). An additional point of interest was to detect the change in trypsin protease inhibitor production in response to treatment with different concentrations of jasmonic acid and abscisic acid using ELISA technique. W e found that both jasmonic acid and abscisic acid ameliorate the adverse effects of drought stress on soybean plant, but treatment with jasmonic acid was more efficient. W e also revealed that production of trypsin inhibitor in soybean plant could take place via a JA- or ABA-depending signalling pathway.