| 總結: | <i>Globodera pallida</i>, a potato cyst nematode (PCN), is a quarantine endoparasitic pest of potato (<i>Solanum tuberosum</i>) in the US due to its effects on yield and quality of potato tubers. A new rhabdovirus, named potato cyst nematode rhabdovirus (PcRV), was revealed and characterized in the <i>G. pallida</i> populations collected in Idaho through use of high-throughput sequencing (HTS) and RT-PCR and found to be most closely related to soybean cyst nematode rhabdovirus (ScRV). PcRV has a 13,604 bp long, single-stranded RNA genome encoding five open reading frames, including four rhabdovirus-specific genes, N, P, G, and L, and one unknown gene. PcRV was found present in eggs, invasive second-stage juveniles, and parasitic females of <i>G. pallida</i>, implying a vertical transmission mode. RT-PCR and partial sequencing of PcRV in laboratory-reared <i>G. pallida</i> populations maintained over five years suggested that the virus is highly persistent and genetically stable. Two other <i>Globodera</i> spp. reproducing on potato and reported in the US, <i>G. rostochiensis</i> and <i>G. ellingtonae</i>, tested negative for PcRV presence. To the best of our knowledge, PcRV is the first virus experimentally found infecting <i>G. pallida</i>. Based on their similar genome organizations, the phylogeny of their RNA-dependent RNA polymerase domains (L gene), and relatively high identity levels in their protein products, PcRV and ScRV are proposed to form a new genus, provisionally named “Gammanemrhavirus”, within the family <i>Rhabdoviridae</i>.
|
|---|
