Screening and characterization of broad-spectrum biocontrol bacteria for seedling damping-off of Pinus koraiensis caused by Fusarium oxysporum
To clarify the biocontrol effect and taxonomic status of the biocontrol bacterium JN4-2,which was screened and obtained by targeting Fusarium oxysporum,the pathogen causing seedling damping-off of Pinus koraiensis,the bacterial inhibitory activity and spectrum of the live bacterium and fermentation broth were determined by plate confrontation method and cylinder plate method,respectively.Meanwhile,the morphological and physiological and biochemical characteristics of JN4-2 were observed,and its 16S rDNA sequence was analyzed.The results showed that 15 antagonistic strains were selected by targeting F.oxysporum,the inhibitory zone width of the live strain JN4-2 against F.osysporum was 22.54 mm,and the diameter of the inhibition zone was 34.60 mm when the fermentation broth was tested against the pathogen.According to its physiological and biochemical characteristics,strain JN4-2 was classified as Streptomyces yellow group.After 16S rDNA sequence analysis and phylogenetic tree construction,JN4-2 is most closely related to S.netropsis,with a homology of 100%.Therefore,strain JN4-2 is temporarily named S.netropsis.This is the first report in China on the application of S.netropsis in the biological control research of the seedling damping-off of Pinus koraiensis,which provides a theoretical basis for the biological control of the seedlings damping-off Pinus koraiensis.
Streptomyces netropsisseedling damping-off of Pinus koraiensisclassification and identificationbiocontrol
万方数据
维普
