Location: National Germplasm Resources LaboratoryTitle: Characterization of a Nepovirus causing a leaf mottling disease in Petunia hybrida Author
Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/18/2017
Publication Date: 3/27/2017
Citation: Bratsch, S., Lockhart, B., Mollov, D.S. 2017. Characterization of a Nepovirus causing a leaf mottling disease in Petunia hybrida. Plant Disease. 101:1017-1021; doi:10.1094/PDIS-12-16-1785-RE. Interpretive Summary: Petunia is a herbaceous annual plant with attractive flowers, and widely used for ornamental purposes. Petunia cuttings that originated from Central America were observed with virus-like symptoms. Spherical virus particles were present in sap from these plants that was examined using transmission electron microscopy (TEM). Healthy plants were mechanically inoculated with sap from the symptomatic plants. The inoculated plants developed the same symptoms, and a virus infection was subsequently confirmed by both TEM and RT-PCR. This new virus was named Petunia chlorotic mottle virus (PCMoV) and its complete genomic sequence was determined. Based on phylogenetic analysis and genomic sequence comparisons to known viruses, PCMoV was characterized as a new member of the genus Nepovirus, family Comoviridae. The completion of the PCMoV genome sequence facilitates developing reliable detection methods and better control measures of this newly described virus. This information will be useful to plant diagnosticians and regulatory agencies, as well as the ornamental and the landscape industries.
Technical Abstract: This report describes the complete genome sequence and characterization of a new virus infecting petunia. Icosahedral virus-like particles were isolated from Petunia hybrida cuttings with interveinal chlorotic mottling. The virus was transmitted by mechanical inoculation from infected to healthy P. hybrida. The virus contains a bipartite RNA genome of 7.6 and 3.8 kilobases. Full genomic sequence was obtained by high throughput sequencing combined with 5’ RACE amplification and reverse transcription PCR at the poly-A tail with oligo-dT and sequence specific primers. Based on particle morphology, genome organization, and phylogenetic analyses it was concluded the new virus is a member of the genus Nepovirus, subgroup A. This new virus was provisionally named Petunia chlorotic mottle virus (PCMoV).