Application of Bacillus species in the control of root rot diseases of crop plants

Bio control potential of three Bacillus spp viz., Bacillus subtilis, B. thuringiensis and B. cereus, against soil borne root-infecting fungi on cowpea and mash bean plants were tested both in vitro and in vivo. All three species showed efficiency and produced nodules on mash bean and cow pea plants. In vitro dual culture plate method showed significant inhibition of Fusarium spp. by all these three species of Bacillus with the appearance of a prominent zone of inhibition while a maximum zone of inhibition of Fusarium spp. was observed by B. thuringiensis, whereas in case of Macrophomina phaseolina and Rhizoctonia solani, the highest zone of inhibition was observed by B. subtilis. Bacillus spp. used as seed dressing and soil drenching showed a significant increase in shoot length, shoot weight, root length and root weight in cow pea and mash bean plants. Maximum shoot length was observed in cow pea plants where Bacillus spp. were drenched in soil, whereas maximum root length and root weight in cow pea was observed when B. thuringiensis used as seed dressing. Seed dressing and soil drenching with species of Bacillus viz., B. subtilis, B. thuringiensis and B. cereus, were found to be an effective method for the control of soil borne root-infecting fungi like M. phaseolina, R. solani and Fusarium spp., on cow pea and mash bean plants.