Submitted to: Plant Disease
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/23/2006
Publication Date: 3/24/2006
Citation: Maroon-Lango, C.J., Hammond, J., Warnke, S. 2006. First Report of Lolium Latent Virus in Ryegrass in the United States. Plant Disease. 90(4):528. Interpretive Summary: Detection of Lolium latent virus (LLV) in ryegrass (Lolium perenne x L. multiflorum) grown in the U.S. is reported. Detection and identification of LLV using three distinct techniques, namely reverse transcriptase polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), electron microscopy is described. This is the first report of the presence of LLV in the U.S.
Technical Abstract: Four genetically distinct plants clonally propagated from a Lolium perenne× L. multiflorum hybrid population established in the U.S. exhibited either no symptoms, or mild chlorotic flecking which coalesced to form chlorotic to necrotic streaking on the leaves. All four plants tested positive by RT-PCR using potexvirus group-specific primers, while three clones tested positive using potyvirus group-specific primers. The cloned potexviral amplicons had high homology to the comparable region of Lolium latent virus–United Kingdom (LLV-UK; GenBank Accession No. DQ333886), whereas the potyviral amplicons were identical to the homologous region of Ryegrass mosaic virus (RGMV). Such results were confirmed by indirect ELISA using the antiserum raised to LLV-Germany and the broad spectrum potyvirus monoclonal antibody, PTY-1. Similar flexous rods were observed by electron microscopy of leaf dip samples and aliquots of the virions purified from mechanically inoculated N. benthamiana.