Wang Ya Rong, Gao Bi Da, Li Xiao Gang, Chen Yi, Zhong Jie, Zhu Jun Zi
Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha City, Hunan Province, PR China.
Yunnan Academy of Tobacco Agricultural Sciences, Kunming, Yunnan Province, PR China.
Virulence. 2025 Dec;16(1):2546683. doi: 10.1080/21505594.2025.2546683. Epub 2025 Sep 13.
Viruses are the most abundant biological entities in natural environments. Mycoviruses or fungal viruses are viruses that infect fungi and are being increasingly recognized. However, their ecological function in regulating microbial communities is not well understood. Here, we analyzed the differentiation of the biological characteristics of 32 strains isolated from rice and confirmed that there was obvious differentiation, especially in virulence. Screening of dsRNA and sequence determination showed that all 32 strains carried viruses displaying a high virus-carrying rate, which was composed of a diverse variety of mycoviruses showing genetic relationships with 15 different families and unclassified virus. In addition, we conducted experiments on multiple horizontal viral infections via hyphal anastomosis between different strains, a simulated ecological environment in a culture dish, and evaluated the dsRNA profiles and virulence of the derivative strains. The results revealed that strains might suffer multiple infections of mycoviruses via mycelial contact between a multitude of strains and lead to virulence differentiation, thus confirming that mycoviruses are an important driving force of virulence differentiation in this fungus. Moreover, a hypovirulent strain, DWZ-6, was obtained via multiple horizontal viral transfers. Overall, this study provides insights into the ecological implications of mycovirus infection in the virulence differentiation of plant pathogenic fungi and the means of obtaining hypovirulent strains with biological control potential, all of which might serve as a basis for monitoring epidemics of fungal plant disease and developing an environmentally friendly biological control approach.
病毒是自然环境中最为丰富的生物实体。真菌病毒是感染真菌的病毒，并且越来越受到人们的关注。然而，它们在调节微生物群落中的生态功能尚未得到充分了解。在此，我们分析了从水稻中分离出的32株菌株生物学特性的差异，证实存在明显差异，尤其是在毒力方面。双链RNA筛选和序列测定表明，所有32株菌株均携带病毒，病毒携带率很高，这些病毒由多种与15个不同科及未分类病毒具有亲缘关系的真菌病毒组成。此外，我们通过不同菌株间的菌丝融合进行了多次水平病毒感染实验，这是一种培养皿中的模拟生态环境，并评估了衍生菌株的双链RNA图谱和毒力。结果表明，菌株可能通过多种菌株间的菌丝接触遭受多种真菌病毒感染，并导致毒力分化，从而证实真菌病毒是这种真菌中毒力分化的重要驱动力。此外，通过多次水平病毒转移获得了一株弱毒株DWZ-6。总体而言，本研究为真菌病毒感染对植物病原真菌毒力分化的生态影响以及获得具有生物防治潜力的弱毒株的方法提供了见解，所有这些都可为监测真菌性植物病害的流行和开发环境友好型生物防治方法奠定基础。
