Isolation of Endophyte Assemblage of Pomegranate from Chitraduraga, District of Karnataka, India: A Preliminary Report
M. B. Geetha
Department of Studies in Food Technology, Shivagangotri, Davangere University, Davanagere, Karnataka-577 007, India.
H. S. Ravikumar Patil *
Department of Studies in Food Technology, Shivagangotri, Davangere University, Davanagere, Karnataka-577 007, India.
*Author to whom correspondence should be addressed.
Abstract
Endophytic microorganisms produce bioactive compounds and are increasingly being investigated as biological control agents for sustainable agriculture. Their roles in fruit crop management are receiving growing attention, and several bacterial endophytes have been reported to exhibit antimicrobial activity. Pomegranate is seriously affected by bacterial blight caused by Xanthomonas axonopodis pv. punicae (syn. Xanthomonas citri pv. punicae; Xcp). Existing blight-management practices have shown variable effectiveness and may have practical limitations; therefore, interest has shifted towards biocontrol-based approaches for sustainable disease management. In fruit crops, bacteria such as Pseudomonas, Erwinia and Bacillus, along with other bacterial and fungal taxa, have been studied as potential biocontrol agents. Previous reports also indicate that the composition and density of endophytic microflora may vary with biotic and abiotic factors, including regional or ecozone-specific conditions associated with disease pressure. The present preliminary study aimed to isolate and characterise the endophyte assemblage associated with pomegranate leaves from Chitradurga district, an area with high blight incidence. We previously reported the isolation of a distinct strain of Xanthomonas axonopodis pv. punicae from this region. The present preliminary findings from leaf-associated isolates indicated the occurrence of Pseudomonas and Erwinia based on cultural and biochemical tests. These observations provide a basis for further studies on host, pathogen and endophyte interactions in pomegranate.
Keywords: Endophytes, pomegranate, Punica granatum L., bacterial blight, Xanthomonas axonopodis pv. punicae, Chitradurga, phylloplane, Pseudomonas, Erwinia, biological control, biochemical characterisation.