Available Genetic Data Do Not Support Adaptation of Tobacco Ringspot Virus to an Arthropod Host

Tobacco ringspot virus (TRSV), a nepovirus, is a long-studied, economically important plant pathogen. Infectious particles are found in pollen and seed and are also vectored by arthropods and nematodes (1). Li and colleagues (2) presented direct evidence of the replicating strand of TRSV in honey bee tissues and showed that TRSV sequence detection rates correlated with season and hive strength in the same manner observed for other viruses known to infect bees. While additional confirmation is desirable (3,4), these observations remain compelling indications that TRSV infects and replicates in honey bees. In contrast to assertions elsewhere (5), detection of TRSV in metagenomic sequence data of honey bees (6) was never represented as evidence of infection. On the other hand, Li and colleagues (2) also presented a phylogenetic argument suggesting that the TRSV lineage that they had identified from beehives was evolutionarily divergent from plant isolates. They postulated that this divergence was driven by adaptive evolution of TRSV to a new host from a different kingdom of life. A new phylogenetic analysis of all public TRSV sequences available in GenBank as of 1 Published 24 January 2017 Citation Cornman RS. 2017. Available genetic data do not support adaptation of Tobacco Ringspot Virus to an arthropod host. mBio 8:e01875-16. https://doi.org/10.1128/ mBio.01875-16. Invited Editor Sue A. Tolin, Virginia Tech Editor Anne K. Vidaver, University of Nebraska Copyright © 2017 Cornman. This is an openaccess article distributed under the terms of the Creative Commons Attribution 4.0 International license. Address correspondence to [email protected].