Surfactin and fengycin contribute to the protection of a Bacillus subtilis strain against grape downy mildew by both direct effect and defence stimulation

• DOI: 10.1111/mpp.12809
• Publication Date: 2019-05-19T04:13:31Z
• Authors: Yan Li; Marie‐Claire Héloir; Xun Zhang; Mareen Geissler; Sophie Trouvelot; Lucile Jacquens; Marius Henkel; Xin Su; Xuewen Fang; Qi Wang; Marielle Adrian
• Keywords: defence; 0301 basic medicine; 570; [SDV]Life Sciences [q-bio]; [SDV.BBM]Life Sciences [q-bio]/Biochemistry; surfactin; Peptides, Cyclic; 630; Plasmopara viticola; Lipopeptides; 03 medical and health sciences; Gene Expression Regulation, Plant; [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology; [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology; Vitis; Molecular Biology; Glucans; Plant Diseases; Peronospora; downy mildew; fengycin; Original Articles; [SDV] Life Sciences [q-bio]; Plant Leaves; lipopeptide; Bacillus subtilis

SummaryBacillus subtilis GLB191 (hereafter GLB191) is an efficient biological control agent against the biotrophic oomycete Plasmopara viticola, the causal agent of grapevine downy mildew. In this study, we show that GLB191 supernatant is also highly active against downy mildew and that the activity results from both direct effect against the pathogen and stimulation of the plant defences (induction of defence gene expression and callose production). High‐performance thin‐layer chromatography analysis revealed the presence of the cyclic lipopeptides fengycin and surfactin in the supernatant. Mutants affected in the production of fengycin and/or surfactin were thus obtained and allowed us to show that both surfactin and fengycin contribute to the double activity of GLB191 supernatant against downy mildew. Altogether, this study suggests that GLB191 supernatant could be used as a new biocontrol product against grapevine downy mildew.