【摘要】 【目的】分离鉴定桑葚果实腐烂的病原菌并筛选对其具有抑菌活性的植物提取物，为桑葚果腐病的绿色防控提供依据。【方法】采用组织分离法分离病原菌并通过真菌形态学及分子生物学对病原菌进行鉴定；采用菌丝生长速率法测定54种植物提取物对桑葚果实腐烂病原菌的抑菌活性，筛选活性较好的提取物，通过浓度梯度进行毒力测定，最后通过显微观察活性较好的提取物(EC₅₀)对菌丝形态的影响。【结果】经形态及分子生物学鉴定该致病菌为易脆毛霉（Mucor fragilis）；当提取物质量浓度为1 mg·mL-1时，青蒿和天蓝鼠尾草乙醇提取物对该菌株有较好的抑菌效果，抑菌率分别为77.72%和49.06%，经毒力测定其抑菌有效中浓度（EC50）分别为0.063、0.107 mg·mL^-1；通过显微镜观察发现，青蒿乙醇提取物可导致病菌菌丝畸变，天蓝鼠尾草对病原菌菌丝形态无明显影响。【结论】本研究发现青蒿和天蓝鼠尾草对桑葚果腐病菌易脆毛霉有较好的抑菌活性，青蒿提取物的抑菌活性尤为显著，EC50仅为0.063 mg·mL^-1，具有进一步开发的价值。更多还原

【Abstract】 【Objective】Pathogen of the fruit rot on mulberries was isolated and identified,and effective antibacterial plant extracts for the disease prevention and control selected.【Method】Tissue separation method was applied to isolate potential pathogens from the infected mulberries.The morphology and molecular biology of the isolates were examined for pathogen identification.Antibacterial activity of 54 plant ethanol extracts was tested to compare the inhibition on the growth of the isolate mycelia.Virulence of the most potent extracts at gradient concentrations was determined along with microscopic observations.【Result】Growth of the identified pathogen,Mucor fragilis was significantly inhibited at a rate of 77.72% by the extract of Artemisia caruifolia on a dosage of 1 mg·mL^-1 rendering an EC₅₀ at 0.063 mg·mL^-1,and also at a rate of 49.06% by Salvia uliginosa with an EC₅₀ at 0.107 mg·mL^-1.In addition to a higher inhibition rate,the A.caruifolia extract induced significant mycelial distortions on the pathogens as shown under the microscope.【Conclusion】Significant antifungal activities against the mulberry rot-causing M.fragilis were found of the ethanol extracts of A.caruifolia and S.uliginosa.With a toxicity of EC₅₀ at 0.063 mg·mL^-1 and significant deformation on the mycelia of the pathogen,A.caruifolia was considered the choice candidate as a biocontrol agent against the disease.更多还原