Submitted to: Plant Disease
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/22/2007
Publication Date: 1/15/2008
Citation: Seifers, D.L., Martin, T., Harvey, T.J., Fellers, J.P., Stack, J., Ryba-White, M., Haber, S., Krokhin, O., Spicer, V., Lovat, N., Yamchuk, A., Standing, K.G. 2008. Triticum Mosaic Virus: A New Virus Isolated From Wheat in Kansas. Plant Disease.92:808-817. Interpretive Summary: In 2006, wheat plants were discovered in Kansas that had mosaic symptoms similar to those caused by Wheat streak mosaic virus (WSMV). However, diagnostic tests determined that the diseased plants did not have WSMV. Other diagnostic tests also determined the disease was not caused by any other known wheat viruses. So, using classic virology techniques, purifications were made from infected plants and using an electron microscope, virus-like particles were found in the purifications. Other tests showed that the virus was similar in physical properties to WSMV, but very different in genetic sequence. It was determined that this was a newly discovered virus, and the name Triticum mosaic virus has been proposed. It is not known where the virus originated, how it is transmitted from plant to plant, or what the optimum environmental conditions are needed for the virus to flourish. Currently, experiments are being undertaken to further characterize the virus and to begin to find genetic resistance in wheat lines.
Technical Abstract: In 2006 a mechanically-transmissible and previously uncharacterized virus was isolated in Kansas from wheat with mosaic symptoms. The physio-chemical properties of the virus were examined by purification on cesium chloride density gradients, electron microscopy, sodium dodecyl sulfate polyacrylalmide gel electrophoresis (SDS-PAGE), sequencing of the nucleotides and amino acids of the coat protein, and immunological reactivity. Purified preparations contained flexous, rod-shaped particles that resembled potyviruses. The coat protein was estimated from SDS-PAGE to have a mass of ca. 35 kDa. Its amino acid sequence, as deduced from DNA sequencing of cloned, reverse-transcribed viral RNA, and separately determined by time-of-flight mass spectrometry, was most closely related (49% similarity) to Sugarcane streak mosaic virus, a member of the Tritimovirus genus of the Potyviridae. The virus gave strong positive reactions in enzyme-linked immunosorbent assays using polyclonal antibodies raised against purified preparations of the cognate virus, but consistent negative reactions against antibodies to Wheat streak mosaic virus (WSMV), other wheat potyviruses and the High Plains virus. When the virus was inoculated on the WSMV-resistant wheat cultivar RonL , systemic symptoms appeared and plant growth was diminished significantly, in contrast with WSMV-inoculated RonL. Taken together, the data supports consideration of this virus as a new potyvirus and the name Triticum mosaic virus (TriMV) is proposed.