Identification of lipopeptide antibiotics of a Bacillus subtilis isolate and their control of Fusarium graminearum diseases in maize and wheat

Abstract

Substances produced by Bacillus subtilis D1/2, a bacterium isolated from cultivated soil, were found to inhibit Fusarium graminearum. The antifungal activity of the bacterium was attributable to major extracellular lipopeptides isolated and identified as fengycins. Their synthesis was enhanced by casamino acids added to the culture medium. The unpurified cell-free spent medium elicited hemolysis with increasing concentration. Its application to fieldcultivated maize and chamber-grown wheat suppressed gibberella ear rot and Fusarium head blight, respectively, when the plants were inoculated with F. graminearum macroconidia. The treatment of maize ears consistently arrested ear-rot development, while the treatment of wheat spikes retarded the progress of Fusarium head blight. Although the deoxynivalenol and ergosterol contents of treated maize kernels were halved, they remained high because of the experimental requirement to inoculate with a high number (1.5 9 10 4 ) of macroconidia. As a potential antifungal agent for controlling Fusarium diseases, B. subtilis D1/2 can be further developed as a useful component of integrated pest management.

Diversity and Active Mechanism of Fengycin-Type Cyclopeptides from Bacillus subtilis XF-1 Against Plasmodiophora brassicae

“…Bacillus subtilis is well known for its biocontrol activity against several plant pathogens and for its role in promoting plant growth [7,19,20,56]. Bacillus subtilis XF-1(hereafter referred to as XF-1), a patented strain with good effects of controlling the pathogen of clubroot in crucifer and many pathogenic fungi [23,24,59,61], can produce a lot of fengycin-type cyclopeptides (FTCPs) such as fengycins (plipastatins) A, B, C, D, and S by the nonribosomal synthetic pathway, and those fengycins showed strong antifungal activities against Fusarium solani, which may be one of XF-1's major weapons against fungi and other pathogens [33].…”

Effects of <i>Bacillus cereus</i> F-6 on Promoting Vanilla (<i>Vanilla planifolia</i> Andrews.) Plant Growth and Controlling Stem and Root Rot Disease

“…Lipopeptide production has been previously noted to play an important role in the successful suppression of phytopathogens [12] [32]. Chan et al [33] have reported that the antifungal activity of the B. subtilis D1/2 against Fusarium graminearum in maize and wheat is attributable to lipopeptides of fengycins. Cao et al [8] have demonstrated that the protection of cucumber plants from attack by Fusarium imparted by B. subtilis SQR 9 is mainly attributed to the antibiotic production of bacillomycin and fengycin.…”

Bacillus lipopeptides as powerful pest control agents for a more sustainable and healthy agriculture: recent studies and innovations

“…tritici (Zhang et al 2017;Yang et al 2018), and Fusarium graminearum (Gong et al 2015). The latter was also inhibited by Bacillus LPs in maize (Chan et al 2009). In potatoes, Bacillus biosurfactants were effective against Fusarium solani (Mnif Table 4.…”