Abstract: To clarify the pathogen species of anthracnose on Euonymus japonicus and screen green biocontrol resources in Ji’nan，Shandong Province，the tissue isolation method was used to isolate pathogens from diseased plants.The taxonomic status of the pathogens was identified via morphological observation，multi‐gene sequence analysis，and pathogenicity test，and the biological characteristics were determined.Further，biocontrol bacteria with significant antagonistic effects against E.japonicus anthracnose were screened from the rhizosphere soil of healthy plants，and their antagonistic activity and control efficacy against the pathogens were evaluated via in vitro dual culture assay and leaf antibacterial test.The results showed that the pathogenic strain EJJN05，isolated from diseased plants，was identified as Colletotrichum siamense through morphological observation，pathogenicity test，and multi‐gene sequence analysis.The optimal growth conditions for this strain were PDA medium，30 ℃ and pH 7.A strain designated as EJSF04 with significant antagonistic effect against the pathogen was isolated from the rhizosphere soil of healthy E.japonicus plants.In dual culture assay，the inhibition rate reached 85.12%，and the in vitro leaf test showed that the fermentation broth of EJSF04 had a control efficacy of 78.32% for preventive treatment of anthracnose，which was significantly higher than that of curative treatment（63.18%）.Combined with morphological observation and 16S rDNA and gyrB gene sequences analysis，strain EJSF04 was identified as Bacillus velezensis.This study provided a solid scientific basis for the effective implementation of green prevention and control measures against E.japonicus anthracnose.

Key words: Euonymus japonicus, Anthracnose, Pathogen identification, Biological characteristics, Biocontrol bacteria, Bacillus velezensis, Antifungal activity

摘要： 为明确山东省济南市大叶黄杨炭疽病的病原菌种类并筛选绿色生防菌资源，采用组织分离法对罹病植株进行病原分离，通过形态特征观察、多基因序列分析及致病性测定鉴定其分类地位，测定其生物学特性，并进一步从健康植株根际土壤中筛选对大叶黄杨炭疽病具有显著拮抗效果的生防菌，通过室内对峙培养和离体叶片抑菌试验，评估生防菌株对病原菌的拮抗能力和防治效果。结果表明，从病株上分离获得病原菌株EJJN05，通过形态学观察、致病性、多基因序列分析将其鉴定为暹罗炭疽菌（Colletotrichum siamense）。该菌最适生长条件为PDA培养基、30 ℃、pH值7。从健康大叶黄杨植株根际土壤中分离得到1株对病原菌具有显著拮抗作用的菌株EJSF04，对峙培养抑菌率达85.12%，离体叶片试验表明，其发酵液对炭疽病的预防处理防效达78.32%，显著高于治疗处理防效（63.18%）。结合形态学观察及16S rDNA和gyrB 基因序列分析，将该菌株鉴定为贝莱斯芽孢杆菌（Bacillus velezensis），为有效实施大叶黄杨炭疽病的绿色防控提供了科学依据和生防资源。

关键词: 大叶黄杨, 炭疽病, 病原鉴定, 生物学特性, 生防菌, 贝莱斯芽孢杆菌, 抑菌活性