TITLE:
Biocontrol of Rhizoctonia solani K1 by Iturin A Producer Bacillus subtilis RB14 Seed Treatment in Tomato Plants
AUTHORS:
Umme Salma Zohora, Takashi Ano, Mohammad Shahedur Rahman
KEYWORDS:
Bacillus subtilis RB14, Rhizoctonia solani K1, Seed Treatment, Iturin A
JOURNAL NAME:
Advances in Microbiology,
Vol.6 No.6,
May
13,
2016
ABSTRACT: Bacillus subtilis RB14 was used as an antagonist against fungal
pathogen Rhizoctonia solani K1 to control
damping-off diseases in tomato plants. Tomato seeds were treated with B. subtilis RB14 culture. The concentration
of bacterial cells for the treatment was about 108 cfu/ml. Treated tomato
seeds showed 99% germination index similar to the untreated seeds. Scanning Electron
Microscopic observations showed a clear evidence of the presence of B. subtilis RB14 on tomato seed surface. Clear
inhibition zone was observed using treated
seed in dual plate assay against R. solani K1. B. subtilis RB14 treated seed showed 80% reduction
in disease incidence during in vivo plant
experiments. B. subtilis RB14 produces
lipopeptide antifungal antibiotic iturin A which could suppress R. solani K1. The phenomenon was
supported by our observation where we found significant amount of iturin A from
the root zone soil of the seed treated plants.