Biochemical characterization of defense responses in rose genotypes in response to artificial inoculation with black spot pathogen Diplocarpon rosae

Resistance responses in the leaves of eight rose genotypes, Knock Out (highly resistant), Arka Nishkant (moderately R. multiflora susceptible), Swadesh IIHRR 13-4 (susceptible), Parimala indica (susceptible) and 4-15-12 exhibiting varied levels resistance against black spot were investigated post artificial inoculation with pathogen, Diplocarpon rosae. There was consistent increase activities defense related enzymes such as catalase, peroxidase, polyphenol oxidase, superoxide dismutase phenylalanine ammonia lyase other secondary metabolites like phenols flavonoids at different phases progression high resistant genotypes Nishkant. The peak activity concentration witnessed during early stages infection while it later phase susceptible genotypes. These results suggested that faster stronger activation system is associated spotin