Role of Brassinosteroids (BRs) in Modulating Antioxidative Defense Mechanism in Plants Growing Under Abiotic and Biotic Stress Conditions

Brassinosteroids (BRs) are a group of steroidal phytohormone that plays an essential role in regulating various chemical and physiological processes involved in plant growth and development. Furthermore, physiological and molecular studies of BRs have revealed their potential of enhancing yield and productivity of crops by regulating variety of genes. But as per current scenario, variety of abiotic and biotic environmental stresses acts as major constraints in yield and productivity of crops. Furthermore, BRs act as nontoxic, environmentally safe steroidal compounds that has the potential in modulating plant responses against abiotic and biotic stresses. When applied exogenously at specific dose and at particular developmental stage of plant, they are known to enhance both quality and quantity of the crop plants. Moreover, BRs are also known to have antifungal, antiviral, and anti-ecdysteroidal properties, which make them potential alternate of chemical fungicide, pesticide, and herbicides. Therefore, keeping in view all these properties of BRs, the current book chapter focuses on the role of BRs in modulating enzymatic and nonenzymatic antioxidant defense mechanism of plants under abiotic and biotic stress conditions.