Taro Vein Chlorosis Nucleorhabdovirus and Other Viruses of Taro in the Pacific

Abstract

The taro virome has been documented to include a few currently known viral species. Among these, Taro vein chlorosis nucleorhabdovirus (TaVCV) is a virus that has been discovered in several different countries across the South Pacific, and, as of 2013, has started to infect taro in Hawaii. Efforts to detect TaVCV in infected taro across regional variants has remained a challenge, as the regional genomic diversity of this virus has been noted to reach as high as 21%. A previous study conducted on Hawaiian TaVCV isolates has determined a very low diversity among local variants, so a sampling method to take infected taro samples from Hawaii, Samoa, Guam, Palau and Vanuatu was conducted to determine the genomic sequences from each of these regions and perform a phylogenetic analysis of these variants. Next-generation sequencing (NGS) performed on double-stranded (ds)RNA found TaVCV genomes that diversified by up to 20% compared to the TaVCV sequence available from GenBank, derived from a Fijian isolate. Additionally, NGS also contributed to the discovery of a unique taro-associated totivirus, which has been fully sequenced and characterized.