1Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi-110 012, India, E-mail: subrata_mithu@yahoo.co.in
2Division of Agricultural Chemicals, Indian Agricultural Research Institute, New Delhi-110 012, India
Online published on 15 October, 2011.
Three out of fifty two, mungbean phylloplane bacteria (Plb) were selected for intensive studies on the basis of their in vitro antagonistic activity against Xanthomonss axonopodss pv. vignaeradiatae, (Xav) the inducer of bacterial leaf spot of mungbean. The three isolates were identified as Bacillus sp. The Plb associated with mungbean were not cyanogenic. The most effective phylloplane bacterium Plb-3 produced four metabolites which were designated as Ba-I, Ba-II, Ba-III, and Ba-IV. Ba-II was most inhibitory against Xav in in vitro with a minimum inhibitory concentration of 250 ppm. Ba-I and Ball were identified as monohydric and polyhydric phenols, whereas, Ba-III contained both hydroxyl and carbonyl group and Ba-IV contained hydroxy! as functional group. Ba-II afforded adequate protection at 500 and 1000 ppm, respectively both on co-inoculation (64% and 76%) as well as 8 h pre-inoculation (50% and 72%).
Phylloplane bacteria, secondary metabolites, Xanthomonas axonopodis pv. vignaeradiatae.
