Antibacterial activity of plant extracts on phytopathogenic Xanthomonas campestris pathovars

Aqueous extracts from leaves of 30 higher plants, collected from different localities, were screened in vitro for antibacterial activity against diffe rent pathovars of the phytopathogenic bacterium, Xanthomonas campestris. Ei ght plant species showed antibacterial activity, based on the zone of inhib ition in a diffusion assay. Significant antibacterial activity was observed in the aqueous extracts of Prosopis juliflora, Oxalis corniculata and Laws onia inermis. The susceptibility of different pathovars of X. campestris to these plant extracts varied. The antibacterial activity of extracts of a f ew plants was comparable with that of the synthetic antibiotics, bacterimyc in and streptocycline. The study indicates the potential of these plant ext racts in the management of diseases caused by X. campestris in several impo rtant crop plants.