Aims

Cotton Verticillium wilt is a very serious soil-borne disease caused mainly by Verticillium dahliae, which severely affects the yield and quality of cotton. There has been an increasing amount of research on the biocontrol of plant disease; however, there is still a lack of effective biocontrol strains.

Methods

In this study, antagonistic endophytic fungi were screened to inhibit V. dahliae, and soil microbiome technologies were used to characterize the biocontrol mechanism.

Results

The strain FUS-8 was isolated from cotton stems; the strain significantly inhibited the growth of V. dahliae and was identified as Fusarium equiseti. FUS-8 had a small amount of cellulase activity, and its fermentation broth significantly inhibited the sporulation and colony formation of V. dahliae. After inoculation with FUS-8 in the greenhouse and field, the disease index significantly decreased. Preinoculation with FUS-8 inhibited the expression of pod. FUS-8 colonized the roots, hypocotyls, and stems of cotton. After preinoculation with FUS-8 in the greenhouse, the Shannon and Sobs indices of fungi and bacteria significantly decreased. The abundance of Bacillus genus in the treatment group was significantly greater than that in the control group 4 days after preinoculation with FUS-8 and 14 days after inoculation with V991. The LDA value of Bacillus in the treatment group was the highest at the genus level after inoculation with FUS-8 only; after reinoculation with V991, Pseudoxanthomonas had the highest LDA value in the treatment group.

Conclusion

FUS-8 altered soil microbial communities, enriched beneficial bacteria, and reduced the incidence of cotton Verticillium wilt.

中文翻译：

---

内生真菌木蕊 FUS-8 对棉花黄萎病的防治效果及其对土壤微生物群落的影响

 目标

棉花黄萎病是一种非常严重的土传病害，主要由大丽轮枝病引起，严重影响棉花的产量和品质。关于植物病害的生物防治的研究越来越多;然而，仍然缺乏有效的生物防治菌株。

 方法

本研究筛选了抑制大丽轮枝菌的拮抗内生真菌，并采用土壤微生物组技术表征了生物防治机制。

 结果

菌株 FUS-8 是从棉茎中分离的;该菌株显著抑制了大丽轮枝菌的生长，被鉴定为马蹄镰刀菌。FUS-8 具有少量的纤维素酶活性，其发酵液显著抑制了大丽轮枝菌的孢子形成和菌落形成。在温室和田间接种 FUS-8 后，病害指数显著降低。预接种 FUS-8 抑制了 pod 的表达。FUS-8 定植于棉花的根、下胚轴和茎。在温室中预接种 FUS-8 后，真菌和细菌的 Shannon 和 Sobs 指数显著降低。治疗组在预接种 FUS-8 后 4 天和接种 V991 后 14 天，芽孢杆菌属的丰度显著大于对照组。仅接种 FUS-8 后处理组芽孢杆菌的 LDA 值在属水平最高;V991 再接种后，假黄单胞菌在治疗组中 LDA 值最高。

 结论

FUS-8 改变了土壤微生物群落，富集了有益细菌，降低了棉花黄萎病的发生率。