In vitro Evaluation of Different Chemicals and Plant Extract against Xanthomonas campestris pv. mangiferae indicae

Different chemicals, plant extracts and two natural products were evaluated in-vitro against the Xanthomans campestris pv. mangiferaeindicae at different concentrations by using paper disc method. Seven different chemicals were evaluated at different concentrations of 500, 1000, 1500 and 2000 ppm including chitosan at 125, 250, 375 and 500 ppm with low, medium and high molecular weight. Chitosan with high molecular weight gave the maximum inhibition zone (51.44 mm) at 500 ppm followed by medium molecular weight chitosan at same concentration and high molecular weight chitosan at 375 ppm concentration whereas, minimum inhibition zone was in captan at 2000 ppm. Various plant extracts and natural products were also evaluated at different concentration of 5,10,15 and 20 per cent. Out of which, only Eucalyptus hybrida proved to be effective in inhibiting the growth of bacterium. Maximum diametric inhibition zone (1.85 mm) was at 20 per cent concentration and minimum was at 5 per cent concentration.