The Potency of Bacillus siamensis LDR as Biocontrol Agent Against Fungal Phytopathogen

Abstract

Bacillus spp. was recognized as biocontrol agent because could produce antifungal towards many phytopathogenic fungi. In relation to study the potency of B. siamensis LDR as biocontrol, antagonistic activity of the bacilli was evaluated against Fusarium sp., Ganoderma sp., and Chaetomium globosum InaCC F228. The antagonist assay was carried out by dual culture method using streak and pour plate technique. Result of antagonistic activity assay with streak technique showed that growth inhibition rate of Fusarium sp., Ganoderma sp., and Chaetomium globosum InaCC F228 were 36.83%, 55.20%, and 33.78%, respectively. Antagonist assay using pour plate technique showed that percentage growth of inhibition for Fusarium sp. (93.96%), Ganoderma sp. (100%), and Chaetomium globosum InaCC F228 (76.64%) were higher than the results from streak method. Furthermore, results from antibiosis assay showed that growth inhibition rate of Fusarium sp., Ganoderma sp., and Chaetomium globosum InaCC F228 were 10.85%, 73.31%, and 30.32% respectively.

Bacillus velezensis TSA32-1 as a Promising Agent for Biocontrol of Plant Pathogenic Fungi

“…Antagonist microorganisms produce several secondary metabolites that can control various phytopathogens. Representatively, some strains of Bacillus velezensis , B. siamensis , and B. subtilis have been proposed as plant pathogen control agents because they produce numerous antimicrobial compounds, such as surfactin, iturin, bacilysin, fengycin, macrolactin, bacillaene, and difficidin [ 8 , 9 ]. In addition, the Bacillus species have the advantage of growing rapidly under simple trophic conditions and produce endospores that make cells more resistant to environmental stress [ 10 ].…”