调查病毒的宿主范围和交叉感染对于更好地了解病毒的流行病学和出现非常重要。以前,我们的研究小组发现了一种植物RNA病毒的自然感染,卷叶花叶病毒(属Cucumovirus,Bromoviridae家族),在植物致病性担子菌真菌中,solani根瘤菌,从田间种植的马铃薯中分离出来。这里,我们进一步扩展了这项研究,以调查在自然条件下植物相关真菌中是否广泛发生类似的植物病毒交叉感染。各种蔬菜植物,如菠菜,芥末叶,萝卜,芹菜,和其他表现出典型病毒样疾病的蔬菜是从山东省的田间收集的,中国。高通量测序显示,至少有11种已知的RNA病毒属于不同的属,包括Potyvirus,Fabavirus,Polerovirus,Waikavirus,还有Cucumovirus,以及属于其他病毒属的新型候选病毒,感染或与收集的蔬菜植物有关,大多数叶子样本含有多种植物病毒。从蔬菜叶样品中分离出大量丝状真菌菌株,并对其进行植物病毒的筛选。RT-PCR和PCR产物的Sanger测序显示,在测试的169株真菌中,大约50%的人携带植物病毒,许多菌株携带多种植物病毒。在真菌分离物中检测到的植物病毒是多样的(10种病毒),并且不限于特定的病毒属。然而,在实验室中长时间维持真菌培养后,许多真菌菌株已经失去了病毒。真菌DNA的测序表明,大多数带有植物病毒的真菌菌株与属于链格孢属的植物病原和/或内生真菌有关,Lecanicillium,和Sarocladium.这些观察结果表明,真菌对植物病毒的非持久性获取可能通常在自然界中发生。我们的发现强调了真菌在生命周期中的可能作用,传播,和植物病毒的进化。
Investigating a virus\'s host range and cross-infection is important for better understanding the epidemiology and emergence of viruses. Previously, our research group discovered a natural infection of a plant RNA virus, cumber mosaic virus (genus Cucumovirus, family Bromoviridae), in a plant pathogenic basidiomycetous fungus, Rhizoctonia solani, isolated from a potato plant grown in the field. Here, we further extended the study to investigate whether similar cross-infection of plant viruses occurs widely in plant-associated fungi in natural conditions. Various vegetable plants such as spinach, leaf mustard, radish, celery, and other vegetables that showed typical virus-like diseases were collected from the fields in Shandong Province,
China. High-throughput sequencing revealed that at least 11 known RNA viruses belonging to different genera, including Potyvirus, Fabavirus, Polerovirus, Waikavirus, and Cucumovirus, along with novel virus candidates belonging to other virus genera, infected or associated with the collected vegetable plants, and most of the leaf samples contained multiple plant viruses. A large number of filamentous fungal strains were isolated from the vegetable leaf samples and subjected to screening for the presence of plant viruses. RT-PCR and Sanger sequencing of the PCR products revealed that among the 169 fungal strains tested, around 50% were carrying plant viruses, and many of the strains harbored multiple plant viruses. The plant viruses detected in the fungal isolates were diverse (10 virus species) and not limited to particular virus genera. However, after prolonged maintenance of the fungal culture in the laboratory, many of the fungal strains have lost the virus. Sequencing of the fungal DNA indicated that most of the fungal strains harboring plant viruses were related to plant pathogenic and/or endophytic fungi belonging to the genera Alternaria, Lecanicillium, and Sarocladium. These observations suggest that the nonpersistent acquisition of plant viruses by fungi may commonly occur in nature. Our findings highlight a possible role for fungi in the life cycle, spread, and evolution of plant viruses.