The Antifungal Effect of Garlic Essential Oil on Phytophthora nicotianae and the Inhibitory Component Involved

• Published in: Biomolecules (Basel, Switzerland) Vol. 9; no. 10; p. 632
• Main Authors: Wang, Yaochen, Wei, Keke, Han, Xiaobin, Zhao, Donglin, Zheng, Yanfen, Chao, Jianmin, Gou, Jianyu, Kong, Fanyu, Zhang, Cheng-Sheng
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI 21.10.2019; MDPI AG
• Subjects: Allyl Compounds - pharmacology; Antifungal Agents - pharmacology; biofumigant; diallyl disulfide; Disulfides - pharmacology; Dose-Response Relationship, Drug; Garlic - chemistry; garlic essential oil; Microbial Sensitivity Tests; Nicotiana - drug effects; Nicotiana - microbiology; Oils, Volatile - pharmacology; Phytophthora - drug effects; phytophthora nicotianae; Plant Components, Aerial - chemistry; Plant Diseases - microbiology; Structure-Activity Relationship; volatiles; Phytophthora nicotianae; garlic essential oil; biofumigant; diallyl disulfide; volatiles
• ISSN: 2218-273X; 2218-273X
• DOI: 10.3390/biom9100632

This study explored the chemical compositions of garlic essential oil, the inhibitory activity of garlic essential oil and diallyl disulfide (DADS) against , and the effects on mycelial plasma membrane permeability and inhibition. In total, 29 compounds were detected in garlic essential oil, of which 26 were detected by gas chromatography‒mass spectrometry (GC-MS) and 21 by headspace solid-phase microextraction (HS-SPME) GC-MS. DADS (60.12% and 19.09%) and trisulfide di-2-propenyl (14.18% and 17.98%) were the major components identified by HS-SPME GC-MS and GC-MS analysis, respectively. Half-inhibitory concentration (Ec50, antagonism) and minimum inhibitory concentration (MIC, fumigation) of DADS against were 150.83 μL/L and 20 μL/L, respectively, while Ec50 of garlic essential oil was 1108.25 μL/L. Mycelial membrane permeability gradually increased in a concentration-dependent manner, and cell death increased at 450 μL/L DADS. Furthermore, DADS treatment significantly reduced the incidence of tobacco black shank and the number of pathogens in rhizosphere soil. DADS also promoted root development of tobacco seedlings at low concentrations, which was inhibited at high concentrations. Therefore, DADS may play an important role in the antifungal effect against by destroying mycelial cell membrane integrity, causing an increase in cell membrane permeability, and leading to cell death.