Studies were conducted to screen out the compatible host and pathogen combination with acid lime and canker causing pathogenic culture of Xanthomonas axonopodis pv. citri (Xac). Among the 21 isolates collected from acid lime cultivating areas of Tamil Nadu, isolate I3 was found to be the most virulent. This compatible combination was tested under controlled environment condition at 28°C and its effect on biochemical parameters of host metabolism was studied. The biochemical changes in the host during the course of pathogenicity include, slight increase in protein, phenol, phenyl alanine ammonia lyase (PAL), β-1, 3-glucanase and chitinase enzymes. Significant increase in the activities of peroxidase (POX), polyphenol oxidase (PPO) and catalase was observed in the infected tissues. Total and non-reducing sugars decreased, but reducing sugar content increased slightly.
Acid lime, Pathogenicity, Xanthomonas axonopodis pv. citri, Biochemical changes
