Changes in Leaf Peroxidase, Polyphenol Oxidase, Catalase and Phenylalanine Ammonia Lyase Due to Alternaria Blight of Clusterbean

摘要

Changes in the specific activity of peroxidase, polyphenol oxidase, catalase and phenylalanine ammonia lyase were determined in healthy and Alternaria blight infected leaves of clusterbean. Three varieties viz, susceptible (RGC-936), moderately resistant (RGC-1003) and resistant (RGC-986) of clusterbean were used in the study. Healthy and diseased leaves samples were collected after 50 days of sowing for various biochemical analyses. Results indicated that the specific activity of peroxidase remainedhigher in diseased leaves of susceptible as compared to moderately resistant and resistant varieties of clusterbean. Polyphenol oxidase activity was found higher in moderately resistant followed by susceptible and resistant varieties of clusterbean. Catalase activity was considerably higher before the inoculation in healthy which decreased after infection in the leaves of all clusterbean varieties. Similarly, activity of phenylalanine ammonia lyase was more in diseased leaves than in healthy leaves ofall three varieties of clusterbean. Therefore, these enzymes play important roles in defence mechanism against Alternaria blight in clusterbean.