Salicylic acid-mediated salt stress tolerance by mitigation of the oxidative effects in Moringa

Faheed, Fayza A.; Hassanein, Ahmed M.; El-nagish, Abdullah A.; Salem, Jehan

doi:10.21608/jesj.2020.204836

Salicylic acid-mediated salt stress tolerance by mitigation of the oxidative effects in Moringa

Document Type : High quality original papers

Authors

¹ Botany and Microbiology Department, Faculty of Science, Sohag University, 82524 Sohag, Egypt.

² Central Laboratory of Genetic Engineering, Botany and Microbiology Department, Faculty of Science, Sohag University, P.O. 82524, Sohag, Egypt.

10.21608/jesj.2020.204836

Abstract

Salinity stress amelioration in Moringa was investigated on five weeks old plants by treatment with salicylic acid (SA) in a pot culture experiment. Salt stressed plants showed a reduction in growth and decreased carotenoid content, while ion leakage and lipid peroxidation increased significantly. To avoid oxidative stress due to salt stress, plants increased significantly the activities of studied antioxidant enzymes [superoxide dismutase (SOD), peroxidase (POX), catalase (CAT), and ascorbate peroxidase (APX)]. A significant increase in the activities of these enzymes was observed, resulted in amelioration of growth inhibition when stressed plants were subjected for exogenous application of SA. The role of esterases in support of antioxidant systems was discussed. Increase of SOD or POX activities under salt stress or SA treatment was not due to expression of new isoenzyme forms but because of overexpression of the turned on iso-loci. SA induced activation of the antioxidant system resulted in a significant increase of carotenoids content but H₂O₂ concentration, lipid peroxidation and ions leakage significantly decreased. These results indicate that SA mediated increase plant content of ROS scavengers and membrane stability leading to promoting more stress tolerance in Moringa.

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