Antibacterial activity of a few medicinal plants against Xanthomonas campestris pv. campestris

Abstract

Antibacterial activity of 12.5%, 25% and 50% alcoholic extracts of leaves of twenty different medicinal plants were investigated by disc diffusion method against gram negative bacteria namely Xanthomonas campestris pv. campestris (plant pathogen) causing black rot disease on cauliflower. It was found that twenty extracts of all the plant samples showed significant activity against the tested bacteria. The plant extracts of Allium cepa, Azadirachta indica, Tamarix aphylla, Vernonia anthelmentica, Plumbago zelanicum, and Tagetes erecta showed significantly good antibacterial activity in 50% concentration against X. c. pv. campestris in vitro and resulted in better seed germination and plant vigour than streptomycin.