The Phylogeography of Potato Virus X Shows the Fingerprints of Its Human Vector

Potato virus X (PVX) occurs worldwide and causes an important potato disease. Complete PVX genomes were obtained from 326 new isolates Peru, which is within the crop′s main domestication center, 10 historical Andes (Bolivia, Peru) or Europe (UK), three Africa (Burundi). Concatenated open reading frames (ORFs) these plus 49 published genomic sequences analyzed. Only 18 of them recombinants, 17 Peruvian. A phylogeny non-recombinant found two major (I, II) five minor (I-1, I-2, II-1, II-2, II-3) phylogroups, included 12 statistically supported clusters. Analysis 488 coat protein (CP) gene sequences, including 128 previously, gave a completely congruent phylogeny. Among I-2 II-3 only contained Andean isolates, I-1 II-2 both other but all II-1 European. I-1, biologically typed isolates. Population genetic dating analyses indicated that emerged after potato’s 9000 years ago was transported to 15th century. Major clusters A–D probably resulted expansions occurred soon late-blight pandemic mid-19th Genetic comparisons populations different Peruvian Departments similarities between those linked by local transport seed tubers for summer rain-watered highland crops, winter-irrigated crops in nearby coastal Departments. Comparisons also showed that, although population diverse evolving neutrally, its spread then elsewhere involved expansion. forms basal Potexvirus genus lineage immediate progenitor unknown. Establishing whether PVX′s entirely phylogroups recombinants threaten production requires future biological studies.