ISSN 2736-1756
Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 14 (9), pp. 001-005, September, 2020. © International Scholars Journals
Full Length Research Paper
Changes of some phenolic compounds and enzyme activities on infected pearl millet caused by Sclerospora graminicola
Kumar Arun*, P. C. Mali and V. K. Manga
Central Arid Zone Research Institute, Jodhpur-342003, India.
Accepted 10 July, 2020
Abstract
Downy mildew or green ear disease of pearl millet caused by Sclerospora graminicola is the most destructive disease. Affected plants produce green ear with various types of proliferations and malformation of the panicle. Deranged physiology of susceptible and resistant varieties is governed by genetic base, pathogen virulence and induced resistance. Phenolic compounds have been noticed most influential secondary products in determination of resistance in pearl millet plants. In relation to this, activities of polyphenol oxidase (PPO), peroxidase (POX), catalase (CAT) and IAA oxidase (IAAO) have also been found deranged considerably in the downy mildew affected plants of susceptible and resistant cultivars. The study suggests that accumulation of total phenols and OD-phenols caused the hyperphenolicity in infected resistant host tissues despite increased activities of POX and PPO. Total amino acids and free proline contents were increased manifold (1222.2 and 942.6%, respectively) in diseased tissues, particularly in resistant cv. HHB 67 than in susceptible one (Eknath), indicating biotic stress caused by S. graminicola. The role of enzyme activities and their related compounds have been discussed in the present paper.
Key words: Pearl millet, downy mildew, Sclerospora graminicola, metabolites, oxidative enzymes, hyperphenolicity.