Chitosan Suppresses Antioxidant Enzyme Activities for Mitigating Salt Stress in Mungbean Varieties

Abstract

An experiment was conducted to evaluate the effect of chitosan on the antioxidant enzyme activity and protein content in four Mungbean varieties (BARI Mung3, BARI Mung6, BINA Mung5 & BINA Mung8) under salinity. Each pot having eight kilograms of soil was ready to grow three plants of each variety. The experiment was comprised with four different conditions in triplicates viz. control, saline (40mM Nacl, 25DAS), saline+chitosan (25ppm chitosan, 30DAS on saline condition) and chitosan (25ppm chitosan on control condition). Seed collections was done at 60 DAS followed by data analysis. Protein content (using H2SO4, CuSO4, K2SO4 & selenium in Kjeldahl method), catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD) (using potassium phosphate buffer, EDTA, H2O2, ascorbate, guaicol) were measured accordingly. Salinity enhanced antioxidant enzyme (CAT (maximum 2.47 mM/ml in BARI Mung3), POD (maximum 0.406 mM/ml in BARI Mung6) and APX (maximum 11.99mM/ml in BINA Mung8)) activities compare to control groups in all four varieties. On the other hand, the significant reduction in protein content during salt stress was drastically increased with chitosan application. However, chitosan played an outstanding stimulating role to reduce antioxidant enzyme activities by scavenging ROS (Reactive Oxygen Species). Therefore, it is suggested that chitosan could be an effective biostimulator to avoid the salinity stress by scavenging ROS.