Assessment of antibiotic and fungicide resistance by indigenous Bacillus strains of cauliflower (Brassica oleracea var. botrytis L.)
Bhawna Dipta and Rajesh Kaushal
The chemical inputs are being used to increase yields, control pathogens, pests, and weeds, but their imbalanced and indiscriminate use over the years resulted in an accumulation of toxic chemical substances in the soil, depletion of organic carbon content and reduction in native micro-flora and fauna, hence lowered the crop productivity. Further the escalating prices of chemical inputs making them dearer to the reach of small and marginal farmers. To reduce these deleterious effects, an efficient alternative method is the application of plant growth promoting rhizobacteria (PGPR). PGPR colonize plant root interiors, migrate to the different plant parts exclusively in the intercellular space and exert beneficial effects on plant growth and development through a wide variety of mechanisms. So, the aim of the present study was to investigate the influence of the four indigenous Bacillus strains viz., Bacillus pumilus MK5, Bacillus sp. MK7, Bacillus sp. MK9 and Bacillus safensis VG1 on antibiotic and fungicide susceptibility. These bacterial cultures were subjected to antibiotic resistance by disc diffusion method. Antibiotics tested were amoxicillin (30 mcg), ampicillin (10 mcg), bacitracin (0.05 mcg), erythromycin (5 mcg), gentamycin 50 mcg), kanamycin (5 mcg) and tetracycline (30 mcg). Further, fungicide resistance to bacterial cultures was performed by well plate assay. Commercial formulation of fungicides were taken at the concentration used under field condition for two major fungicides i.e. mancozeb (0.12, 0.25, 0.37%) and carbendazim (0.05, 0.10, 0.15, 0.20%). Results revealed that all the bacterial strains were sensitive to amoxicillin, ampicillin, erythromycin, gentamycin, kanamycin and tetracycline but showed resistance to bacitracin. Further it was observed that all bacterial isolates showed tolerance to low concentrations of fungicides.
How to cite this article:
Bhawna Dipta, Rajesh Kaushal. Assessment of antibiotic and fungicide resistance by indigenous Bacillus strains of cauliflower (Brassica oleracea var. botrytis L.). Pharma Innovation 2018;7(5):26-28.