Diversity and chemotaxis of soil bacteria with antifungal activity against Fusarium wilt of banana

• Published in: Journal of industrial microbiology & biotechnology 2012-10, Vol.39 (10), p.1495-1505
• Main Authors: Li, Ping, Ma, Li, Feng, Yun Li, Mo, Ming He, Yang, Fa Xiang, Dai, Hao Fu, Zhao, You Xing
• Format: Article
• Language: English
• Subjects: 4-hydroxybenzoic acid; Agricultural biotechnology; Agriculture; alcohols; alkanes; Alkenes; antagonists; Antifungal Agents - metabolism; antifungal properties; Antimicrobial agents; Attractants; Bacillaceae; Bacillus-Staphylococcus group; Bacteria; Bacteria - classification; Bacteria - genetics; Bacteria - isolation & purification; Bacteria - metabolism; Bananas; Biochemistry; Bioinformatics; Biological and medical sciences; Biological products; Biomedical and Life Sciences; Biotechnology; chemical composition; chemotaxis; Chemotaxis - physiology; Competition; diagnostic techniques; Disease; Enterobacteriaceae; Environmental Microbiology; Fundamental and applied biological sciences. Psychology; Fusarium - classification; Fusarium - physiology; Fusarium oxysporum; Fusarium wilt; Genes, Bacterial - genetics; Genetic Engineering; Inorganic Chemistry; Kinases; Laboratories; Life Sciences; Microbiology; Microorganisms; Musa; Musa - microbiology; naphthalenes; nucleotide sequences; Paenibacillaceae; Pathogens; Pest Control, Biological; Phylogenetics; Phylogeny; Plant Diseases - microbiology; Plant Roots - chemistry; Plant Roots - microbiology; Polymorphism, Restriction Fragment Length; Pseudomonadaceae; restriction fragment length polymorphism; Rhizosphere; rhizosphere bacteria; ribosomal DNA; RNA, Ribosomal, 16S; root exudates; salicylic acid; Signal transduction; Soil Microbiology; Studies; swarms; wilting
• ISSN: 1367-5435; 1476-5535
• DOI: 10.1007/s10295-012-1163-4

The chemotactic response of bacteria to root exudates plays an important role in the colonization of bacteria in the rhizosphere. In this study, 420 strains of antifungal bacteria against Fusarium oxysporum f. sp. cubense (Foc) were screened for chemotaxis based on a cheA molecular diagnostic method. A total of 124 strains with antifungal efficiencies of 27.26–67.14 % generated a characteristic band of cheA. The chemotaxis of 97 bacterial strains producing a cheA band was confirmed using the drop assay and swarm plate assay using catechol, p-hydroxybenzoic acid, salicylic acid, and asparagine as the attractants. A phylogenetic analysis based on restriction fragment length polymorphisms (RFLPs) and 16S rDNA sequences indicated that the 124 chemotactic antagonists of Foc were affiliated with 18 species of Paenibacillaceae, Bacillaceae, Streptomycineae, Enterobacteriaceae, and Pseudomonadaceae. The chemical composition of banana root exudates were analyzed by GC–MS, and 62 compounds, including alkanes, alkenes, naphthalenes, benzenes, and alcohols, were evaluated. Five representative antagonists of Foc showed 1.76- to 7.75-fold higher chemotactic responses than the control to seven compounds in banana root exudates, as determination by capillary assays.