Effect of exogenous application of methyl jasmonate on physiological and biochemical characteristics of Brassica napus L. cv. Talaye under salinity stress

Salt stress caused by high soil salinity is one of the most serious limiting factors threatening crop production in many parts of the world. To alleviate stressful conditions such as salinity, various plant growth regulators, such as jasmonates, are involved. In the present study, the effect of exogenously applied methyl jasmonate (MeJA) on physiological and biochemical characteristics of rapeseed (Brassica napus L. cv. Talaye) was studied in combination with different concentrations of NaCl under greenhouse conditions. Plants treated only with NaCl stress showed a significant decrease in growth parameters and photosynthesis rate and a significant increase in CO2 compensation point, respiration rate, soluble sugar content, malondialdehyde content, proline content and antioxidant enzymes activities when compared with the control. Exogenously applied MeJA mitigated the inhibitory effect of salt stress on these variables at all NaCl levels. Exogenously applied MeJA counteracted the inhibitory effects of NaCl by increasing relative water content, soluble sugar content and photosynthesis rate.