中国农业科学 ›› 2026, Vol. 59 ›› Issue (13): 2841-2852.doi: 10.3864/j.issn.0578-1752.2026.13.007

• 植物保护 • 上一篇    下一篇

2-辛基-3-异噻唑啉酮抗烟草赤星病菌的生物活性及作用机制

郭富强1,2(), 彭治鑫1(), 李得瑞3, 林木森4, 许立峰1,5, 张成省1()   

  1. 1 中国农业科学院烟草研究所/国家农业环境微生物种质资源库(山东), 山东青岛 266100
    2 山东中烟工业有限责任公司济南卷烟厂, 济南 250000
    3 云南省烟草公司文山州公司西畴县分公司, 云南文山 663599
    4 贵州省烟草公司遵义市公司, 贵州遵义 562400
    5 青岛农特生物科技有限公司, 山东青岛 266100
  • 收稿日期:2026-03-04 接受日期:2026-04-08 出版日期:2026-07-01 发布日期:2026-07-01
  • 通信作者:
    张成省,E-mail:
  • 联系方式: 郭富强,E-mail:gfq15194316071@163.com。彭治鑫,E-mail:P18671073969@163.com。郭富强和彭治鑫为同等贡献作者。
  • 基金资助:
    国家自然科学基金(32572904); 中国烟草总公司重大科技项目(110202401018(LS-08)); 山东省农业重大应用技术创新项目(SD2019ZZ002)

Biological Activity and Mechanism of 2-Octyl-3-isothiazolinone Against Alternaria alternata Causing Tobacco Brown Spot

GUO FuQiang1,2(), PENG ZhiXin1(), LI DeRui3, LIN MuSen4, XU LiFeng1,5, ZHANG ChengSheng1()   

  1. 1 Institute of Tobacco Research, Chinese Academy of Agricultural Sciences/National Agricultural Environmental Microbial Resource Bank (Shandong), Qingdao 266100, Shandong
    2 Ji’nan Cigarette Factory of China Tobacco Shandong Industrial Co., Ltd., Ji’nan 250000
    3 Xichou County Branch of Yunnan Tobacco Company Wenshan Prefecture Company, Wenshan 663599, Yunnan
    4 Zunyi Company of Guizhou Tobacco Company, Zunyi 562400, Guizhou
    5 Qingdao Nongte Biotechnology Co., Ltd., Qingdao 266100, Shandong
  • Received:2026-03-04 Accepted:2026-04-08 Published:2026-07-01 Online:2026-07-01
  • Supported by:
    中国烟草总公司重大科技项目(110202101057(LS-17))

摘要:

【目的】明确棘孢木霉(Trichoderma asperellum)HG1和枯草芽孢杆菌(Bacillus subtilis)Tpb55共培养代谢产物2-辛基-3-异噻唑啉酮对烟草赤星病菌(Alternaria alternata)的抑制效果及其对病原菌生理代谢的影响,为该类天然产物在植物真菌病害防治上的应用提供理论依据。【方法】采用菌丝生长速率法测定8种共培养次级代谢物对烟草赤星病菌的抑菌活性,明确2-辛基-3-异噻唑啉酮的毒力并计算EC50;通过田间试验评价其对烟草赤星病的防治效果;利用转录组测序解析2-辛基-3-异噻唑啉酮处理后对烟草赤星病菌基因表达的影响;测定ATP含量与ATP酶活性揭示其对烟草赤星病菌能量代谢的作用;采用PI染色及活性氧检测分析其对烟草赤星病菌细胞膜的完整性与氧化应激的影响。【结果】10 µg·mL-1浓度下,2-辛基-3-异噻唑啉酮对烟草赤星病菌的抑制率为100%,显著优于阳性对照药物菌核净(抑制率为27.60%),田间试验中,100和200 µg·mL-1浓度下的防治效果分别为80.80%和84.33%,与阳性对照药物40%菌核净400倍液防治效果相当(80.15%),且对烟草本身无毒害作用。转录组测序分析表明,2-辛基-3-异噻唑啉酮通过双重机制发挥其抑菌作用:一方面显著抑制糖酵解及三羧酸循环关键酶,阻断病原菌的能量代谢;另一方面,病原菌活性氧清除相关基因(AALT_g9032AALT_g9033)表达量均显著下调,最终导致活性氧的大量积累,造成氧化损伤,破坏细胞膜完整性与生物功能。进一步验证表明,2-辛基-3-异噻唑啉酮可显著降低烟草赤星病菌的ATP含量及ATP酶活性,干扰其能量代谢;PI染色结果显示,该化合物以浓度依赖性方式破坏病原菌细胞膜的完整性;DCFH-DA荧光染色表明,其可诱导菌丝内活性氧大量积累,引发氧化应激,加剧细胞损伤。上述结果与转录组分析所得结论一致。【结论】2-辛基-3-异噻唑啉酮作为一种具有广阔应用前景的绿色农药,通过能量阻断-氧化损伤协同作用来干扰烟草赤星病菌生命活动的正常进行。研究结果可为2-辛基-3-异噻唑啉酮作为新型抗菌剂防治烟草赤星病提供理论依据与应用支撑。

关键词: 2-辛基-3-异噻唑啉酮, 烟草赤星病菌, 抑菌活性, 转录组分析, 作用机制

Abstract:

【Objective】The objective of this study is to clarify the inhibitory effect of 2-octyl-3-isothiazolinone, a metabolite from the co-culture of Trichoderma asperellum HG1 and Bacillus subtilis Tpb55, on Alternaria alternata (the pathogen causing tobacco brown spot) and its impact on the physiological metabolism of the pathogen, and to provide a theoretical basis for the application of this natural product in the management of plant fungal diseases.【Method】The antifungal activities of eight secondary metabolites from the co-culture against A. alternata were assessed using the mycelial growth rate method. The toxicity of 2-octyl-3-isothiazolinone was evaluated, and its EC50 value was calculated. Field trials were conducted to determine its control efficacy against tobacco brown spot. Transcriptome sequencing was employed to analyze the gene expression profiles of A. alternata following treatment with 2-octyl-3-isothiazolinone. The impact on energy metabolism was assessed by measuring ATP content and ATPase activity. Propidium iodide (PI) staining and reactive oxygen species (ROS) detection were used to evaluate cell membrane integrity and oxidative stress levels, respectively.【Result】At a concentration of 10 μg·mL-1, 2-octyl-3-isothiazolinone exhibited 100% inhibition against A. alternata, which was significantly superior to that of the positive control dimethachlon (27.60%). In the field experiment, the control efficacies at concentrations of 100 and 200 μg·mL-1 were 80.80% and 84.33%, respectively, which were equivalent to that of the positive control (40% dimethachlon diluted 400-fold, 80.15%), and there was no toxic effect on tobacco itself. Further studies showed that 2-octyl-3-isothiazolinone exerted its antifungal effect through a dual mechanism: on the one hand, it significantly inhibited the key enzymes of glycolysis and the tricarboxylic acid cycle, blocking the energy metabolism of the pathogen; on the other hand, the expression levels of genes related to ROS scavenging in the pathogen (AALT_g9032, AALT_g9033) were significantly down-regulated, eventually leading to the massive accumulation of ROS, causing oxidative damage and destroying the integrity and biological function of the cell membrane. Further verification demonstrated that 2-octyl-3-isothiazolinone significantly reduced ATP content and ATPase activity, confirming disruption of energy metabolism. PI staining revealed concentration-dependent damage to cell membrane integrity, while DCFH-DA fluorescence staining indicated substantial intracellular ROS accumulation, triggering oxidative stress and exacerbating cellular damage. These results were consistent with the transcriptomic findings.【Conclusion】As a green pesticide with broad application prospects, 2-octyl-3-isothiazolinone interferes with the normal life activities of A. alternata through the synergistic effect of energy blockage-oxidative damage. This study provides a theoretical basis and application support for its use as a new antifungal agent to control tobacco brown spot.

Key words: 2-octyl-3-isothiazolinone, Alternaria alternata, antifungal activity, transcriptome analysis, mechanism of action