Some Enzymatic and Non-Enzymatic Antioxidants in Cowpea Vigna Unguiculata L. under the Influence of Foliar Spraying with Vitamin C, Salicylic Acid, and their Interaction

ABSTRACT The current study is conducted to find out the effect of leaf spray of vitamin C and salicylic acid along with their combination on various enzymes and non-enzymatic antioxidant contents of the cowpea plant (Vigna unguiculata L.). In this connection, three levels of salicylic acid (0, 40, and 80 mg·L⁻¹) and four levels of vitamin C (0, 50, 100, and 150 mg·L⁻¹) were taken. Various parameters such as peroxidase and catalase enzyme activity and concentration of salicylic acid, glutathione, total ascorbate, and proline were recorded. RCBD technique with three replicates and 36 experimental units was adopted in this study. The results revealed that: 1.Both salicylic acid and vitamin C had a positive effect on the studied traits. 2.Higher concentrations of both substances contributed to increased values for all the studied traits. 3. The interaction of Salicylic acid and Vitamin C levels especially the high levels of both affected the enzymatic and non-enzymatic antioxidant activities of the cowpea plants studied positively.