Characterization of Cucurbit Aphid-Borne Yellows Virus (CABYV) from Passion Fruit in Brazil: Evidence of a Complex of Species within CABYV Isolates

High-throughput sequencing (HTS) has been an important tool for the discovery of plant viruses and their surveillance. In 2015, several virus-like symptoms were observed in passion fruit (PF) plants in Bahia state, Brazil. Using HTS technology, bioinformatics tools, RT-PCR, and Sanger sequencing, we identified the cucurbit aphid-borne yellows virus (CABYV, Polerovirus, Solemoviridae) in co-infection with cowpea aphid-borne mosaic virus (CABMV, Potyvirus, Potyviridae) in PF, in green manure, and spontaneous plants in several localities in Bahia. Complete genomes of CABYV-PF isolates were determined and analyzed with other CABYV isolates available in GenBank that have been identified in various countries. Phylogenetic analysis and pairwise identity comparison with CABYV isolates showed that CABYV-PFs are more closely related to French and Spanish isolates. Overall, analyses of all the CABYV genomes revealed that these could represent ten distinct species, and we thus proposed reclassifying these CABYV as isolates into ten species, tentatively named Polerovirus curcubitaeprimum to Polerovirus curcubitaenonum, and Polerovirus melo. CABYV-PF is a member of Polerovirus curcubitaeprimum.

Automated summary

High-throughput sequencing (HTS) is an important tool for discovering and monitoring plant viruses. In passion fruit (PF) plants in Bahia state, Brazil, co-infections of cucurbit aphid-borne yellows virus (CABYV) and cowpea aphid-borne mosaic virus (CABMV) were identified using HTS technology, bioinformatics tools, RT-PCR, and Sanger sequencing. Phylogenetic analysis showed CABYV-PF to be closely related to French and Spanish isolates, and the complete genomes suggested the presence of ten distinct CABYV species, including Polerovirus curcubitaeprimum and Polerovirus melo.