Fusarium oxysporum is an important phytopathogenic fungus, it can be controlled by the soil fumigant methyl isothiocyanate (MITC). However, the antimicrobial mechanism of MITC against F. oxysporum, especially at the transcriptional level, is still unclear. In this experiment, the antimicrobial mechanism of MITC against F. oxysporum was investigated. Our results indicated that when F. oxysporum was exposed to 6 mg/L MITC for 12 h, the inhibitory rate of MITC on F. oxysporum was 80%. Transmission electron microscopes showed that the cell wall and membrane of F. oxysporum had shrunk and folded, vacuoles increased, and mitochondria swelled and deformed. In addition, the enzyme activity of F. oxysporum treated with MITC showed a decrease of 32.50%, 8.28% and 74.04% in catalase, peroxidase and superoxide dismutase, respectively. Transcriptome sequencing of F. oxysporum was performed and the results showed that 1478 differentially expressed genes (DEGs) were produced in response to MITC exposure. GO and KEGG analysis showed that the DEGs identified were involved in substance and energy metabolism, signal transduction, transport and catalysis. MITC disrupted cell homeostasis by influencing the expression of some key genes involved in chitin synthase and detoxification enzymes production, but F. oxysporum also protected itself by up-regulating genes involved in energy synthesis (such as upregulating acnA, CS and LSC2 in TCA). qRT-PCR data validated the reliability of transcriptome data. Our research used biochemical and genetic techniques to identify molecular lesions in the mycelia of F. oxysporum exposed to MITC, and provide valuable insights into the toxic mechanism of pathogenic fungi mediated by MITC. These techniques are also likely to be useful for rapidly screening and identifying new, environmentally-friendly soil fumigants that are efficacious against fungal pathogens.

尖孢镰刀菌是一种重要的植物病原真菌，可用土壤熏蒸剂异硫氰酸甲酯(MITC)对其进行防治。然而，MITC 对F的抗菌机制。尖孢菌，特别是在转录水平上，仍不清楚。本实验探讨了 MITC 对F的抗菌机制。对尖孢菌进行了研究。结果表明，当尖孢镰刀菌接触6 mg/L MITC 12 h时，MITC对尖孢镰刀菌的抑制率为80%。透射电镜观察显示，尖孢镰刀菌细胞壁和膜收缩、折叠，液泡增多，线粒体肿胀变形。此外，MITC处理后的尖孢镰刀菌过氧化氢酶、过氧化物酶和超氧化物歧化酶活性分别降低了32.50%、8.28%和74.04%。对尖孢镰刀菌进行转录组测序，结果显示，MITC 暴露后产生了 1478 个差异表达基因 (DEG)。 GO和KEGG分析表明，鉴定的DEGs参与物质和能量代谢、信号转导、运输和催化。 MITC 通过影响一些参与几丁质合酶和解毒酶产生的关键基因的表达来破坏细胞稳态，但尖孢镰刀菌也通过上调参与能量合成的基因（例如上调 TCA 中的 acnA、CS 和 LSC2）来保护自身。 qRT-PCR 数据验证了转录组数据的可靠性。 我们的研究利用生化和遗传技术来识别暴露于 MITC 的尖孢镰刀菌菌丝体中的分子病变，并为 MITC 介导的病原真菌的毒性机制提供有价值的见解。这些技术也可能有助于快速筛选和鉴定可有效对抗真菌病原体的新型环保土壤熏蒸剂。