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.