Integrated biological and chemical control of damping-off caused by Rhizoctonia solani using Bacillus subtilis RB14-C and flutolanil.

Bacillus subtilis RB14-C was isolated as a potential biological agent to control the occurrence of various plant diseases. Integrated control of damping-off in tomato plants caused by Rhizoctonia solani was carried out in pots using B. subtilis RB14-C and chemical pesticide, flutolanil. The growth of RB14-C was the same in both the flutolanil-containing and the flutolanil-free media, indicating the resistance of RB14-C to flutolanil. Although the productivity of surfactin decreased to one-third in the flutolanil-containing medium, compared with that in the flutolanil-free medium, the productivity of iturin A which is mainly associated with the suppressive ability of RB14-C against plant pathogens was unaffected. The integration of RB14-C and flutolanil reduced the amount of flutolanil used to one-fourth of that of the single use of flutolanil, with the same efficacy of reducing disease occurrence.