中国香菇核心种质真菌病毒多样性检测及其携带特点分析

Mycovirus diversity in Chinese Lentinula edodes core collections

摘要:

【背景】香菇病毒通常具有潜隐性特征，携带病毒的香菇菌株往往并不表现出明显症状，然而一旦发生常造成较大的经济损失。【目的】解析中国香菇核心种质中真菌病毒多样性特点。【方法】以56个中国香菇核心种质为试验材料，采用RT-PCR和RT-qPCR检测技术对34种香菇病毒携带情况进行检测和分析。【结果】研究结果表明，分别有14种和5种香菇病毒的目标基因在绝大多数阳性菌株中扩增出较亮和较暗的条带，RT-qPCR结果也表明阳性带毒香菇菌株中病毒目标基因的扩增结果与病毒含量呈正相关，即病毒在阳性菌株中的含量越高则病毒扩增条带越亮；被检测的34种香菇病毒中，LeFV5和LeMV1检测率为100%；21个栽培种质和35个野生种质中分别有8种和6种香菇病毒检测率为80%以上，而且其中4种病毒相同(LeDFV2、LeFV2、LeSV和LeHV2)；栽培菌株和野生菌株携带病毒数分别为8-21种和9-23种，平均每个菌株携带16.4种和16.7种。【结论】香菇种质资源中普遍携带复杂的多种真菌病毒，被检测的病毒在阳性菌株中扩增亮度不同，而且存在明显遗传差异的香菇菌株中携带的一些高检测率病毒相似，暗示这些病毒在香菇进化早期就存在。

Abstract:

[Background] Viruses in Lentinula edodes lie latent for long periods before the appearance of symptoms. However, once reactivated, they will cause great economic loss. [Objective] To analyze the mycovirus diversity in Chinese L. edodes core collections. [Methods] RT-PCR and RT-qPCR were used to detect 34 types of mycoviruses in 56 core collections of Chinese L. edodes. [Results] The target genes of 14 and 5 types of viruses in most of the positive strains showed bright and faint bands, respectively. The brightness of the bands was positively correlated with virus content. To be specific, the higher the virus content in the positive strain, the brighter the band. Among the 34 viruses, LeFV5 and LeMV1 were detected in all the 56 core collections. The detection rates of 8 viruses in 21 cultivated strains and 6 viruses in 35 wild strains were over 80% and 4 viruses (LeDFV2, LeFV2, LeSV, and LeHV2) were shared by the two. The cultivated strains and wild strains carried 8-21 and 9-23 viruses, respectively, with 16.4 and 16.7 on average. [Conclusion] L. edodes germplasms generally carry a variety of complex mycoviruses. The amplified bands have different brightness in positive strains. L. edodes germplasms with great genetic difference share some viruses with high detection rate, suggesting that these viruses arose early in the evolution of L. edodes.