香蕉中内源条斑病毒的基因型及其激活

Genotypes of endogenous Banana streak virus and their activation

为明确香蕉中不同基因型内源条斑病毒(endogenous Banana streak virus,eBSV)的激活及其机制,根据eBSOLV-GD(endogenous Banana streak OL virus Guangdong)的结构设计引物,采用内源条斑病毒基因型分析方法及RT-PCR检测法对其基因型、表达和激活进行了研究。结果表明,只含A基因组的香蕉不含eBSOLV-GD;含B基因组的香蕉均含eBSOLV-GD。在所检测的含B基因组的香蕉中eBSOLV-GD可分为6种基因型,部分为感染型的eBSOLV-GD。粉蕉和大蕉中eBSOLVGD的片段Ⅱ和Ⅲ能表达,eBSOLV-GD经组织培养后可激活产生BSOLV-GD,引起香蕉发病,发病率为8.6%~18.0%,表明发病率的高低与香蕉的基因型有关,与eBSV基因型无关。

In order to study the activation and its mechanism of endogenous Banana streak virus( eBSV)of different genotypes,the primers were designed according to the structure of endogenous Banana streak OL virus Guangdong( eBSOLV-GD) to analyze the genotypes,expression and activation of eBSOLV-GD.The results showed that the banana that contains only A genome did not contain eBSOLV-GD; however the banana that contains B genome contained eBSOLV-GD. There are six eBSOLV-GD genotypes in all tested bananas which contain B genome,some of which are infectious. The internal fragments II and III in eBSOLV-GD of Plantain and Pisang Awak subgroup were expressible. eBSOLV-GD of Plantain and Pisang Awak subgroup could be activated to form BSOLV-GD and cause streak disease. The incidence of streak disease was related with different banana subgroups but not with different eBSV genotypes after tissue culture.