The morpho-physiological responses of a tolerant and sensitive wheat (Triticum aestivum L.) cultivar to drought stress and exogenous methyl jasmonate

Abstract

One of the most significant abiotic factors that has a negative impact on wheat productivity globally is drought. To comprehend the impacts of drought on wheat and propose remedies, numerous studies are carried out on various wheat varieties. In this study, 50 µM of methyl jasmonate (MeJA) was applied to tolerant Gün 91 and sensitive Bezostaja wheat cultivars and they were exposed to drought stress for 15 days. The responses of MeJA application on wheat development and physiology, as indicators of drought tolerance, were investigated comparatively. Wheat's morphology was negatively impacted by drought stress, which also decreased the crop’s relative water content (RWC) and protein content while raising its soluble sugar level. Furthermore, Gün 91, a tolerant cultivar, came to the fore as the cultivar with higher shoot-root length, RWC, total soluble sugar and protein contents compared to Bezostaja cultivar as a result of drought application. Exogenous MeJA application, cause to increase in content of osmolytes (total soluble sugar, protein) compared to the drought group and had an improving effect in maintaining the water status of wheat seedlings. Hence, the RWC increased from 48.90% to 66.87% in the tolerant Gün 91 cultivar, but no change was observed in Bezostaja cultivar. Applying 50 μM of MeJA increased the protein by 4.42%, total soluble sugar by 19.92%, and RWC by 36.74% in Gün 91 cultivar while increasing protein by 3.11% and total soluble sugar by 11.02% in Bezostaja cultivar. Moreover, there is not any significant effect of MeJA observed on the shoot-root length of both cultivars and the RWC of Bezostaja cultivar. When all results are evaluated together, exogenous MeJA application may positively affect the response of wheat seedlings, and minimize the damaging effects so we can suggest using MeJA and cultivars that are resistant to drought stress for wheat yield.