Abstract:

In order to obtain broad spectrum antagonistic strains，we isolated 25 Actinomycetes strains and 8 antagonist strains from healthy soil that had been cropping banana plants for a number of years in Hainan Province using Fusarium oxysporum f. sp. cubense Race 4 and 8 other pathogens as indicative strains. The antibacterial activity of the antagonistic bacteria was evaluated by plate confrontation，containing medium and thin layer chromatography methods. One of the strains，designated B-03，showed a strong and stable control effect against nine pathogens with the inhibition of mycelium growth of 48.34% to 85.43%，and the inhibition of spore germination rate of 38.43% to 80.14%. It also inhibits mycelium growth and spore germination of F. oxysporum Race 4 by 85.43% and 80.14%，respectively. Based on the morphological characteristics，cultural characteristics，physiological and biochemical characteristics，cell wall composition and 16S rDNA sequence analysis，the strain was identified as Streptomyces lunalinharesii. Pot experiment showed that the control effect of the strain fermentation broth on banana Fusarium wilt reached 72.72%. Taken together，our results suggest that the strain S. lunalinharesii could provide a new resource for biological control of banana Fusarium wilt disease.

Key words: banana, Streptomyces, banana Fusarium wilt disease, antagonistic bacterial, identification, application