Antioxidant Enzyme Activities In Local Soybean Plants Exposed To Salinity Stress

Abstract

Salt stress severely reduces the production of soybean (Glycine max) cultivar, an essential cash crop. High salt levels have detrimental effects on growth, nodulation. Several studies have shown that the tolerance to saltwater intrusion of many crops can be induced by increasing activities of various antioxidant enzymes, fortified the capacity to maintain ion and osmotic homeostasis, thus metabolism in addition to structural adaptations. As salinity and drought are known as osmotic stress and impose similar impacts on plants, the aim of this study was to explore if the two soybean cultivars that were previously identified with contrasting drought tolerance would also display contrasting salinity tolerance abilities. The investigation was carried out by comparing activities of major antioxidants enzymes of between the MTD720 (drought-sensitive cultivar) and DT51 (drought-tolerant cultivar). The obtained findings revealed that MTD720 had lower activity levels of superoxide dismutase, catalase, and peroxidase than DT51, especially under high and/or long salinity treatment conditions, indicating a better antioxidant defense in the drought-tolerant cultivar. However, more replicates should be used to statistically identify any significant difference between these two cultivars regarding antioxidant activities. In addition, molecular and physiological investigations could be performed in future studies to find out the underlying mechanisms that DT51 relies on for responses against salinity stress.