Submitted to: Plant Disease
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/28/2004
Publication Date: 4/1/2005
Citation: Robertson, N.L., Ianson, D.C. First report of turnip mosaic virus in rhubarb in Alaska. Plant Disease. April 01, 2005, Vol. 89 #4 page: 430 Interpretive Summary: As part of the National Plant Germplasm System, the Arctic Plant Germplasm Introduction and Research Project maintains the national rhubarb collection in Palmer, Alaska. During the growing seasons of 2003-4, one of the rhubarb cultivars, Rheum rhababarum 'Kerwin' developed red lesions on the leaves. The causal agent or pathogen responsible for the leaf symptoms was determined to be the plant virus, Turnip mosaic virus (TuMV). The TuMV-infected plants were removed from the site to avoid further spread of the virus to the other rhubarb cultivars. Although TuMV infects many different plant species throughout the world this is the first report of TuMV in Alaska.
Technical Abstract: Turnip mosaic virus (TuMV) was detected in two Rheum rhababarum 'Kerwin' plants on the Arctic Germplam Introduction and Research Project site in Palmer, Alaska. The infected plants contained leaves with noticeable red lesions. Sap extracts and partially purified virus samples were mechanical inoculated to experimental host plants, resulting in local lesions on leaves of Chenopodium amaranticolor, C. quinoa, and red lesions on Rheum palmatum and R. hybridum. Definitive TuMV identity from these leaves was determined by a compound direct enzyme-linked immunoserological assay (ELISA) and western blots using polyclonal/monoclonal antibodies to TuMV. Total RNA extracts from rhubarb leaves (Qiagen) was used in RT-PCR (reverse transcription-polymerase chain reaction) with specific primers for TuMV. The predicted PCR product (~1.132-bp) containing the 3'-terminal fragment encompassing the coat protein gene, was cloned and sequenced. The TuMV rhubarb isolate had up to 97% amino acid and 96% nucleotide identities to other TuMV isolates from NCBI (National Center for Biotechnology Information) using Blast searches. This is the first report of TuMV in Alaska.