采用水蒸气蒸馏法制备杜香（Rhododendron tomentosum Harmaja）叶挥发油，通过气相色谱-质谱联用（GC-MS）技术对叶挥发油化学成分进行分离和鉴定，初步探索了叶挥发油对8种致病细菌和1种致病真菌以及4种植物病原菌的抑菌效果。结果显示：宽叶杜香叶挥发油中共鉴定到46个化学成分，其中，octahydro-2,5-methano-1H-indene和7-ethyl-1,3,5-cycloheptatriene相对含量较高（分别为21.15%和18.92%）。不同质量浓度宽叶杜香叶挥发油对8种细菌和白色念珠菌（Candida albicans）均有一定程度的抑制作用，其中，对金黄色葡萄球菌（Staphylococcus aureus）的最小抑菌浓度（MIC）最低（2 mg·mL^-1），对白色念珠菌的MIC值为2 mg·mL^-1；宽叶杜香叶挥发油对4种植物病原菌具有显著抑制作用，其中，对水稻纹枯病菌（Rhizoctonia solani）的半数效应浓度（EC₅₀）最低（0.19 mg·mL^-1）。综合研究结果显示：宽叶杜香叶挥发油具有广谱抗菌作用，枯茗醛、4-萜烯醇和α-蒎烯可能是其发挥抑菌活性的主要成分。

The leaf volatile oil of Rhododendron tomentosum Harmaja was prepared by using steam distillation, the chemical components of the leaf volatile oil were separated and identified by using gas chromatography-mass spectrometry （GC-MS） technology, and the inhibitory effects of the leaf volatile oil against eight pathogenic bacteria, one pathogenic fungus, and four plant pathogens was preliminarily explored. The results show that a total of 46 chemical components are identified in leaf volatile oil of L. palustre var. dilatatum, among which, the relative contents of octahydro-2,5-methano-1H-indene and 7-ethyl-1,3,5-cycloheptatriene are relatively high （which are 21.15% and 18.92%, respectively）. The leaf volatile oil of L. palustre var. dilatatum exhibits a certain degree of inhibitory effect on eight bacteria and Candida albicans at different mass concentrations, among which, the minimum inhibitory concentration （MIC） against Staphylococcus aureus is the lowest （2 mg·mL^-1）, and the MIC value against C. albicans is 2 mg·mL^-1; the leaf volatile oil of L. palustre var. dilatatum has significant inhibitory effects on four plant pathogens, among which, the median effective concentration （EC₅₀） against Rhizoctonia solani is the lowest （0.19 mg·mL^-1）. It is suggested that the leaf volatile oil of L. palustre var. dilatatum possesses a broad-spectrum antimicrobial effect, and cuminal, terpinen-4-ol, and α-pinene may be the main components responsible for its antimicrobial activity.