| 摘要: |
| 【 目的】筛选高效防控烟草根腐病的化学药剂与拮抗菌，构建菌药协同复配剂，以实现对烟草根腐病 的绿色高效防控。【 方法】以烟草根腐病菌（Fusarium oxysporum）JL003为靶标，采用菌丝生长速率法筛选能高效抑 制烟草根腐病 JL003 的化学药剂；利用逐级稀释法从盐爪爪根际土壤中分离菌株，采用皿内拮抗结合活体接种法筛选 生防菌并进行耐盐性测定，采用形态观察和分子手段鉴定筛选的生防菌株；通过相融性测定构建菌药复配剂，并利用 活体接种法筛选能够高效抑制烟草根腐病的菌药复配剂。【 结果】50%多菌灵可湿性粉剂、43%戊唑醇悬浮剂和45%咪鲜胺水乳剂对烟草根腐病菌JL003菌丝生长的EC50分别为0.095 5，0.841 3和0.235 9 mg/L，能显著抑制烟草根腐病菌的生长。从盐爪爪根际土壤中筛选出的菌株YZZ-5对烟草根腐病菌JL003的皿内抑制率为45.60%，活体抑制率为61.92%，在含质量分数1%，10%和12% NaCl的LBA培养基上均能正常生长，形态学结合16S rDNA和GyrA序列鉴定其为贝莱斯芽孢杆菌（Bacillus velezensis）。菌药相融性测定结果显示，50%多菌灵可湿性粉剂与43%戊唑 醇悬浮剂在稀释4 000倍浓度下对YZZ-5的抑菌圈直径均为0.15 mm，与YZZ-5具有一定的相融性。43%戊唑醇悬浮剂和50%多菌灵可湿性粉剂与YZZ-5等量复配后对烟草根腐病的抑制率分别为96.37%和85.47%，显著高于单个药剂处理。【 结论】50%多菌灵可湿性粉剂、43%戊唑醇悬浮剂与耐盐生防菌贝莱斯芽孢杆菌YZZ-5复配能够显著提高化学药剂和生防菌对烟草根腐病的防治效果，达到在减药的同时提升防控效果，为烟草根腐病的综合防控提供参考。 |
| 关键词: 烟草根腐病 尖孢镰刀菌 化学药剂 生防菌 菌药复配剂 |
| DOI：10. 13207/j. jnwafu. 2026. 11. 015 |
| 分类号: |
| 基金项目:内蒙古自治区自然科学基金项目（2024MS03056）；湖南中烟工业有限责任公司科研计划项目（KY2024YC0019）；内蒙古农业大学高层次人才科研启动项目（NDYB2018-3，NDYB2019-1，NDYB2018-14） |
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| Construction of a fungicide⁃biocontrol agent combination for controlling root rot in tobacco |
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ZHANG Haotian1, SUN Pingping1, WU Ziyuan1, LUO Chaopeng2, LI Zhengnan1
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1.College of Horticulture and Plant Protection，Inner Mongolia Agricultural University，Hohhot，Inner Mongolia 010018，China;2.Zhengzhou Tobacco Research Institute of CNTC，Zhengzhou，Henan 450001，China
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| Abstract: |
| 【 Objective】The study aims to screen highly effective chemical fungicides and antagonistic microorganisms against tobacco root rot，and construct a synergistic combination for green and efficient control of the disease.【Method】Chemical agents that effectively inhibit Fusarium oxysporum JL003 were screened using the mycelial growth rate method. The serial dilution method was used to isolate strains from the rhizosphere soil of Kalidium scoparium.Subsequntly，the biocontrol agents were screened by a combination of in vitro antago-nism tests and in vivo inoculation assays. The salt tolerance of antagonistic strains was determined，and they were identified through morphological observation and molecular analysis.Based on compatibility tests，com-bined bacterial-agent formulations were constructed. and these formulations were screened for efficient agents against tobacco root rot using live plant inoculation.【Result】The EC50 values of 50% carbendazim wettable powder，43% tebuconazole suspension concentrate，and 45% prochloraz emulsion in water against the mycelial growth of F.oxysporum JL003 were 0.095 5，0.841 3，and 0.235 9 mg/L，respectively.These agents significantly inhibited the pathogen’s growth. Strain YZZ-5，isolated from the rhizosphere of K scoparium，exhibited inhibition rates of 45.60% in vitro and 61.92% in vivo. It grew normally on LBA medium containing 1%，10%，and 12% NaCl，and was identified as Bacillus velezensis based on morphological characteristics combined with 16S rDNA and GyrA rDNA sequence analysis. The compatibility tests showed that at a concentration of 4 000 times dilution，50% carbendazim WP and 43% tebuconazole SC formed an inhibition zone of only 0.15 mm against strain YZZ-5，indicating a certain degree of compatibility. The inhibition rates of the equal-volume combinations of YZZ-5 with 43% tebuconazole SC and 50% carbendazim WP against tobacco root rot were 96.37% and 85.47%，respectively，which were both significantly higher than those of the individual agents.【Conclusion】Combining 50% carbendazim WP and 43% tebuconazole SC with the salt-tolerant biocontrol agent B.velezensis YZZ-5 significantly enhanced the control efficacy against tobacco root rot. This strategy achieves effective disease management while reducing chemical usage，thereby providing a foundation for the in-
tegrated control of tobacco root rot. |
| Key words: tobacco root rot Fusarium oxysporum chemical fungicides biocontrol agent microbial and pharmaceutical compound agent |
