Bacillus cabrialesii BH5 Protects Tomato Plants Against Botrytis cinerea by Production of Specific Antifungal Compounds

Abstract

The gray mold caused by the phytopathogen Botrytis cinerea presents a threat to global food security. For the biological regulation of several plant diseases, Bacillus species have been extensively studied. In this work, we explore the ability of a bacterial strain, Bacillus cabrialesii BH5, that was isolated from tomato rhizosphere soil, to control the fungal pathogen B. cinerea. Strain B. cabrialesii BH5 showed a strong antifungal activity against B. cinerea. A compound was isolated and identified as a cyclic lipopeptide of the fengycin family by high-performance liquid chromatography and tandem mass spectrometry (ESI-MS/MS) that we named fengycin H. The fengycin H-treated hyphae of B. cinerea displayed stronger red fluorescence than the control, which is clearly indicating that fengycin H triggered the hyphal cell membrane defects. Moreover, root inoculation of tomato seedlings with BH5 effectively promoted the growth of tomato plants. Transcription analysis revealed that both BH5 and fengycin H stimulate induced systemic resistance of tomato plants via the jasmonic acid signaling pathway and provide a strong biocontrol effect in vivo. Therefore, the strain BH5 and fengycin H are very promising candidates for biological control of B. cinerea and the associated gray mold.

Bacillus velezensis SYL-3 suppresses Alternaria alternata and tobacco mosaic virus infecting Nicotiana tabacum by regulating the phyllosphere microbial community

“…Among the reported beneficial microorganisms and biological agents, Bacillus spp. has been widely applied in the management of various plant diseases ( Shafi et al, 2017 ; Yang et al, 2020 ; Zhou et al, 2021 ). Here, phylogenetic analysis indicated that SYL-3 showed high sequence identity and clustered closely with species B. velezensis .…”

Antifungal activities of Bacillus velezensis FJAT‐52631 and its lipopeptides against anthracnose pathogen Colletotrichum acutatum

“…Bacillus species (such as B. subtilis , B. amyloliquefaciens , B. velezensis , B. nakamurai , and B. siamensis ) possess a broad spectrum of antifungal activities and can effectively inhibit various fungal pathogens, which highlighting the applicable potential of Bacillus species in controlling the development of fruit postharvest fungal diseases, such as peach brown rot (caused by Monilinia fructicola or Monilinia laxa ) [31], ring rot (caused by Botryosphaeria dothidea ) [32], gray mold (caused by Botrytis cinereal ) [33], anthracnose (caused by C. gloeosporioides or C . acutatum ) [34], citrus decay (caused by Penicillium digitatum , P. expansum , or P. italicum ) [35].…”

“…The iturin families are naturally antifungal agents displaying strong activities against Fusarium graminearum, C. gloeosporioides, C. acutatum, Saccaromyces cerevisiae, Alternaria alternate, B. cinerea, Fusarium oxysporum, and Rhizoctonia solani by damaging the plasma membranes to form a large pore and inhibiting hypha growth [43][44][45]. Fengycins are known to exhibit antimicrobial activities against Rolani stolonifera [46,47], F. oxysporum [48], F. graminearum [49], M. fructicola [50], Rhizomucor variabilis [51], Candida albicans [52], Sclerotinia sclerotiorum [53], B. dothidea [32], B. cinerea [33], C. gloeosporioides, C. musae [54], C. acutatum [34], and Ralstonia solanacearum [22] via destruction of the plasma membranes or the cell wall, cell lysis, inhibition of DNA synthesis and accumulation of ROS, consequently causing cell death. Most of surfactins exert their strong antibacterial activities against Staphylococcus aureus, Enterobacter sp.…”

“…The surface of the mycelia in the treated groups appeared swollen, lumpy, and wrinkled (Figure2b,c). The results of SEM observation indicated that lipopeptides secreted from FJAT-52631 could distinctly affect the growth of C. acutatum by disrupting the mycelium surface structure.4 | DISCUSSIONBacillus species (such as B. subtilis, B. amyloliquefaciens, B. velezensis, B. nakamurai, and B. siamensis) possess a broad spectrum of antifungal activities and can effectively inhibit various fungal pathogens, which highlighting the applicable potential of Bacillus species in controlling the development of fruit postharvest fungal diseases, such as peach brown rot (caused by Monilinia fructicola or Monilinia laxa)[31], ring rot (caused by Botryosphaeria dothidea)[32], gray mold (caused by Botrytis cinereal)[33], anthracnose (caused by C. gloeosporioides or C. acutatum)[34], citrus decay (caused by Penicillium digitatum, P. expansum, or P. italicum)[35]. For examples, B. subtilis CPA-8 was able to inhibitT A B L E 3 Diameter of inhibition zone of the purified lipopeptides produced by Bacillus velezensis FJAT-52631 against Colletotrichum acutatum FJAT-30256 The test concentrations of iturin and fengycin are 60 and 5 mg/ml; the test concentrations of surfactin are 1.25, 2.5, and 5 mg/ml.…”

Biocontrol of strawberry gray mold caused by Botrytis cinerea with the termite associated Streptomyces sp. sdu1201 and actinomycin D

“…Traditionally, chemical control has been the most effective strategy for strawberry gray mold control for years (de Moura et al, 2021;Fontana et al, 2021;Zhou et al, 2021). However, frequent and large-scale use of numerous fungicides leads to the increasingly serious "3R" problems (Resistance, Resurgence and Residue) (de Moura et al, 2021).…”