Molecular and biological characterization of a distinct species of Lolavirus infecting different accessions of seashore paspalum, a turfgrass, widely grown in the United States

Abstract

Seashore paspalum (Paspalum sp.), is an economically significant grass used in golf courses, sports fields, and landscaping in the United States. A novel Lolavirus, tentatively named paspalum latent virus (PaLV), was identified for the first time in seashore paspalum plants from the USDA National Plant Germplasm System (NPGS) using high-throughput sequencing. Three complete genome sequences of PaLV from different Paspalum accessions, with a length of 6,995 nucleotides (nt), not including the poly(A) tail, were obtained by Rapid Amplification of cDNA Ends and Sanger sequencing. Phylogenetic analysis based on the replicase protein sequences from the Alphaflexiviridae family revealed that PaLV grouped with the Lolavirus genus, with the closest relative being Lolium latent virus (LoLV). PaLV shares less than 72% nt identity to the replicase and coat protein genes of LoLV, which demarks PaLV as a new species and the second member of the genus. Furthermore, the coat protein region showed intense negative selection pressure and low spatially structured diversity. Host range analysis of PaLV showed that wheat, corn, sorghum, and Lolium are systemic hosts of PaLV. A one-step RT-PCR technique was developed to reliably detect PaLV infection.