EFFECTS OF CHITOSAN OLIGOSACCHARIDE ON ANTIOXIDANT ENZYME ACTIVITIES IN LOCAL SOYBEANS EXPOSED TO SALINITY STRESS

Abstract

Soybean is a valuable crop, however, its high sensitivity to salinity is considered as a limitation to soybean production. Therefore, it is worthwhile to find out how to enhance the ability to salt tolerance. This research investigates the role of chitosan oligosaccharide (COS) in mitigating oxidative stress in plants under salinity stress, focusing on its impact on hydrogen peroxide (H₂O₂) levels and the antioxidant enzyme activities (superoxide dismutase, catalase, peroxidase) in the leaf tissues. The research was carried out by comparing these parameters at different concentrations of COS foliar spray (0 ppm, 100 ppm, 200 ppm) under salinity stress (100 mM NaCl) and normal conditions. This study shows that COS application was effective in alleviating oxidative stress. Especially among the three tested COS concentrations, the results showed that COS 100 ppm yielded the most promising outcomes for stress mitigation by lowering degree of H2O2 accumulation under salinity stress as well as enhancing significantly antioxidant enzyme activities including the H2O2 – scavengers catalase and peroxidase. Therefore, this highlights the potential use of COS as a robust and green reagent for enhancing plant stress tolerance. The findings of this study could have significant implications for developing strategies to enhance stress tolerance in crops through the application of bio- stimulants like COS and contribute to ecosystem sustainability.