Spetz C, Taboada A M, Darwich S, Ramsell J, Salazar L F, Valkonen J P T
Department of Plant Biology and Forest Genetics, Genetics Centre, SLU, PO Box 7080, SE-750 07 Uppsala, Sweden.
International Potato Center (CIP), Apartado 1558, Lima, Peru.
J Gen Virol. 2003 Sep;84(Pt 9):2565-2578. doi: 10.1099/vir.0.19208-0.
Peru is a centre of origin and domestication of the potato, pepper and tomato (family Solanaceae). Many potyviruses (genus Potyvirus) that infect these crops were described 20-30 years ago. However, definitive classification of these viruses as distinct species remains unresolved for several reasons, including their close serological relationships, similar symptomatology in test plants and lack of genomic sequence data. Using samples collected from Peru, we have determined the complete genomic sequence of two strains of Peru tomato virus (PTV) as well as near-complete sequences for two additional PTV strains. We also obtained partial sequences of four strains of Potato virus V (PVV). Comparisons with genomic sequences of Wild potato mosaic virus (WPMV), Potato virus Y (PVY), Pepper mottle virus (PepMoV), Potato virus A (PVA) and other potyviruses established that all these viruses constitute different taxa (species). Phylogenetic comparisons indicated that PTV, PVV and WPMV are the most closely related species which, together with PepMoV, PVY, Pepper yellow mosaic virus and Pepper severe mosaic virus, constitute a group that is distinguishable from other potyviruses. Therefore, the members of this group may share a common ancestor. PVA does not belong to this group. PVV and PTV were also closely related serologically. However, PTV did not cross-protect against PVV and WPMV in tobacco plants or complement systemic infection of PVV and WPMV in pepper plants. Two biologically and phylogenetically distinguishable strain groups were identified within PTV and PVV. In future studies, the sequence data and virus-specific primers and probes for PTV, PVV and WPMV described in this study will enable accurate indexing of plants with respect to either single or mixed infection with these viruses.
秘鲁是马铃薯、辣椒和番茄（茄科）的起源和驯化中心。许多感染这些作物的马铃薯Y病毒属病毒在20至30年前就已被描述。然而，由于多种原因，包括它们密切的血清学关系、在试验植物中相似的症状表现以及缺乏基因组序列数据，这些病毒作为不同物种的明确分类仍未解决。利用从秘鲁采集的样本，我们确定了秘鲁番茄病毒（PTV）两个株系的完整基因组序列以及另外两个PTV株系的近乎完整序列。我们还获得了马铃薯V病毒（PVV）四个株系的部分序列。与野生马铃薯花叶病毒（WPMV）、马铃薯Y病毒（PVY）、辣椒斑驳病毒（PepMoV）、马铃薯A病毒（PVA）和其他马铃薯Y病毒属病毒的基因组序列比较表明，所有这些病毒构成不同的分类单元（物种）。系统发育比较表明，PTV、PVV和WPMV是关系最密切的物种，它们与PepMoV、PVY、辣椒黄花叶病毒和辣椒严重花叶病毒一起构成了一个与其他马铃薯Y病毒属病毒可区分的类群。因此，该类群的成员可能有共同的祖先。PVA不属于这个类群。PVV和PTV在血清学上也密切相关。然而，PTV在烟草植株中不能交叉保护抵御PVV和WPMV，在辣椒植株中也不能补充PVV和WPMV的系统感染。在PTV和PVV中鉴定出了两个生物学和系统发育上可区分的株系组。在未来的研究中，本研究中描述的PTV、PVV和WPMV的序列数据以及病毒特异性引物和探针将能够对感染这些病毒的单一或混合感染的植物进行准确检测。
