Relationship between extracellular polysaccharides production and aggressiveness of Xanthomonas axonopodis pv. punicae causing bacterial blight of pomegranate

Extracellular polysachharides (EPS) are abundantly produced by several plant pathogenic bacteria especially by those inhabiting the phyllosphere. besides their role in protecting the bacteria from hostile environmental conditions, they play a diverse role in bacterial aggregation, and hence virulence. In the current study, EPS from twenty seven isolates of Xanthomonas axonopodis pv. punicae were quantified and correlated with aggressiveness of the pathogen. The EPS production ranged 2.64mg/100ml in Xap125 to 5.19mg/100ml in Xap102. High Pearson correlation coefficient (0.88) was observed during 0–10 days of inoculation suggesting the possible role of EPS in facilitating the bacteria to establish itself during early stages of infection.