枯草芽孢杆菌XH-1对稻瘟病菌抑菌活性分析及田间防效初探OA

[Objective]The present paper aimed to explore the application potential of Bacillus subtilis strain XH-1 in the biocontrol of rice blast.[Method]The antifungal activity of XH-1 against Magnaporthe oryzae was assessed using a plate confrontation assay.The effects of XH-1 on various stages of the fungus,including conidial production(evaluated on complete medium,CM),conidial germination(induced on hydro-phobic slides),development of infection structures(induced by leaf sheath inoculation),and pathogenicity(via spray inoculation)were in-vestigated.The application potential of XH-1 was further analyzed through field efficacy trials.[Result]The plate confrontation analysis be-tween XH-1 and Guy11 showed that XH-1 could inhibit the colony growth of Guy11,with an inhibition rate of 85.75％.When XH-1 was added to CM medium,the colony growth of M.oryzae was severely inhibited,with inhibition rates of 99.55％(1×),90.91％(10×)and 50.23％(100 ×),respectively,while conidiation was sharply curtailed.Spore-germination assays revealed that XH-1 not only blocks conidi-al germination but also suppresses appressorium formation.Observation of sheath infection showed that XH-1 fermentation broth could effec-tively inhibit the infection process of Guy11.Pathogenicity analysis showed that XH-1 fermentation broth could inhibit the pathogenicity of Guy11 on rice.The field control effect test showed that XH-1 fermentation broth can suppress the onset of rice blast in the field.[Conclu-sion]The B.subtilis XH-1 demonstrates promising potential against rice blast and shows considerable application prospects,providing a valua-ble resource for the biological control of this disease.