PR enzyme activities of Cercospora theae causing bird's eye spot disease in tea plants (Camellia sinensis (L.) O.Kuntze).

摘要

A total of three isolates of Cercospora theae namely KC10, MC24 and VC38 obtained from birds eye spot disease were used for the present study and subjected to various Pathogen Related (PR) enzymatic secretion by the pathogen and the plant as a response to the disease attack. The enzyme secreted from the pathogen includes CMCase, amylase, invertase, pectinase and protease, its activity was studied at various incubation periods ranging from 15, 30, 60, 90 and 120 min. All enzymes except amylase, exhibited its maximal activity at 30 min incubation period whereas amylase exhibited its optimal activity at 60 min of incubation. The study revealed that C. theae was capable of producing the range of pathogenic enzymes and exhibited its maximal activity at 10th day harvest. The said enzyme activities was also studied in healthy and C. theae infected tea leaves including chitinase, DNase, Phenylalanine Ammonia Lyase (PAL), Tyrosine Ammonia Lyase (TAL), polyphenol oxidase (PPO), peroxidase (PO) and catalase in order to detect the level of defensive response. The significance of the specific enzymatic activity detected in C. theae isolates and tea leaves were discussed by correlating to the plant pathogenesis. This study showed that phyopathogenic isolates of C. theae is capable of producing various carbohydrases, pectinases and protease and defensive enzymes along with phenolic and oxidative enzymes. The significance of correlating the enzymatic activity with the virulence of the isolates was ascertained and discussed. The enzyme profile studies of the pathogenic isolates assist in understanding and revealing of host-pathogen interaction.