Genome Characterization and Pathogenicity of Two New Hyptis pectinata Viruses Transmitted by Distinct Insect Vectors

Phytopathology. 2022 Nov;112(11):2440-2448. doi: 10.1094/PHYTO-04-22-0130-R. Epub 2022 Nov 22.

Abstract

Two newly described viruses belonging to distinct families, Rhabdoviridae and Geminiviridae, were discovered co-infecting Hyptis pectinata from a tropical dry forest of Ecuador. The negative-sense RNA genome of the rhabdovirus, tentatively named Hyptis latent virus (HpLV), comprises 13,765 nucleotides with seven open reading frames separated by the conserved intergenic region 3'-AAUUAUUUUGAU-5'. Sequence analyses showed identities as high as 56% for the polymerase and 38% for the nucleocapsid to members of the genus Cytorhabdovirus. Efficient transmission of HpLV was mediated by the pea aphid (Acyrthosiphon pisum) in a persistent replicative manner. The single-stranded DNA genome of the virus tentatively named Hyptis golden mosaic virus (HpGMV) shared homology with members of the genus Begomovirus with bipartite genomes. The DNA-A component consists of 2,716 nucleotides (nt), whereas the DNA-B component contains 2,666 nt. Pairwise alignments using the complete genomic sequence of DNA-A of HpGMV and closest relatives showed identities below the cutoff (<91% shared nt) established by the ICTV as species demarcation, indicating that HpGMV should be classified in a distinct begomovirus species. Transmission experiments confirmed that the whitefly Bemisia tabaci Middle East-Asia Minor 1 (MEAM1) is a vector of HpGMV.

Keywords: aphid transmission; begomovirus; cytorhabdovirus; weed; whitefly transmission.

MeSH terms

  • Animals
  • Begomovirus* / genetics
  • Genome, Viral / genetics
  • Hemiptera*
  • Hyptis* / genetics
  • Insect Vectors
  • Nucleotides
  • Phylogeny
  • Plant Diseases
  • Rhabdoviridae* / genetics
  • Virulence

Substances

  • Nucleotides