title: Isolation and characterization of endophytic streptomycete antagonists of Fusarium wilt pathogen from surface-sterilized banana roots.
abstract: A total of 131 endophytic actinomycete strains were successfully isolated from surface-sterilized banana roots. These isolates belonged to Streptomyces (n=99), Streptoverticillium (n=28), and Streptosporangium (n=2) spp. The remaining 2 isolates were not identified. About 18.3% of the isolates inhibited the growth of pathogenic Fusarium oxysporum f. sp. cubense on banana tissue extract medium. The most frequently isolated Streptomyces sp. strain S96 was similar to Streptomyces griseorubiginosus. About 37.5% of the S. griseorubiginosus strains were antagonistic to F. oxysporum f. sp. cubense. The antagonism of strain S96 was lost when FeCl(3) was introduced into the inhibition zone. In vivo biocontrol assays showed that the disease severity index (DSI) was significantly (P=0.05) reduced and mean fresh weight increased (P=0.001) in plantlets treated with strain S96 compared to those grown in the absence of the biocontrol strain. These findings indicate the potential of developing siderophore-producing Streptomyces endophytes for the biological control of fusarium wilt disease of banana.
authors.affiliation: State Key Laboratory for Biocontrol and Department of Biochemistry, School of Life Sciences, Zhongshan (Sun Yatsen) University, Guangzhou 510275, PR China.
authors.forename: Lixiang
authors.initials: L
authors.lastname: Cao
authors.forename: Zhiqi
authors.initials: Z
authors.lastname: Qiu
authors.forename: Jianlan
authors.initials: J
authors.lastname: You
authors.forename: Hongming
authors.initials: H
authors.lastname: Tan
authors.forename: Shining
authors.initials: S
authors.lastname: Zhou
mesh_terms: D000898:Antibiosis; D002681:China; D002712:Chlorides; D005290:Ferric Compounds / Q000378:metabolism; D005670:Fusarium / Q000254:growth & development*; D028521:Musa / Q000382:microbiology*; D010572:Pest Control, Biological / Q000379:methods; D010935:Plant Diseases / Q000382:microbiology; D018517:Plant Roots / Q000382:microbiology*; D017262:Siderophores / Q000502:physiology; D013306:Streptomycetaceae / Q000145:classification / Q000302:isolation & purification* / Q000502:physiology
chemical_list: D002712:Chlorides; D005290:Ferric Compounds; D017262:Siderophores; C024555:ferric chloride