Submitted to: Archives of Virology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/5/2001
Publication Date: 3/1/2002
Citation: KOENIG, R., BERGSTROM, G., GRAY, S.M. A NEW YORK ISOLATE OF SOIL-BORNE WHEAT MOSAIC VIRUS DIFFERS FROM THE NEBRASKA TYPE ISOLATE IN THE NUCLEOTIDE SEQUENCE OF CODING REGIONS, BUT NOT IN THE DEDUCED AMINO ACID SEQUENCE. ARCHIVES OF VIROLOGY. 2002. V. 147. P. 617-625. Interpretive Summary: Soil borne wheat mosaic virus (SBWMV) is widespread throughout much of the Midwestern United States wheat growing area, but only recently has the virus become pronounced in the eastern United States. The disease can have a serious impact on wheat yields, but the yellowing symptoms are often misdiagnosed as nutrient deficiencies. The virus, which is transmitted by soil-inhabiting microorganisms, is often associated with wet areas in production fields which can give rise to stressed and yellowed plants. Some wheat varieties adapted to Midwestern conditions do possess high levels of WSBMV resistance, however there was an apparent breakdown in resistance in some wheat cultivars when grown in New York. These observations prompted an investigation of the virus populations to determine if a change in the virus may be responsible for differences in host reaction. Following biological and serological characterization of WSBMV isolates from New York, they were sent to a colleague in Germany who has studied diversity of WSBMV isolates from around the world. Results indicate that while all US isolates are serologically identical, they vary considerably in nucleotide sequence of several genes. Based on this information RNA-based diagnostic assays can be used to distinguish among US WSBMV isolates. Although the RNA sequences were variable among virus isolates, the protein sequences coded for by the RNA were identical suggesting a great need to conserve protein sequence to maintain biological function. Further studies are required to determine if the differences in host reaction to US virus isolates have a genetic basis or if environmental
Technical Abstract: A wheat-infecting furovirus found in Tompkins County, New York, U.S.A. was identified as a strain of Soil-borne wheat mosaic virus (SBWMV) by means of sequence analyses of portions of its RNA 1 and 2. The nucleotide sequences of several of its genes differed by c. 9 to 12 % from those of the corresponding genome regions of the Nebraska type strain of SBWMV. The deduced amino acid sequences of the putative translation products, however suggested much closer relationships. Thus, the amino acid sequences of the coat proteins of the two virus strains were 100% identical despite the fact that their coding regions differed in as many as 68 nucleotide positions. The New York (NY) strain of SBWMV is possibly identical to an isolate from Illinois for which so far only the nucleotide sequences of its coat protein gene and the adjacent 3'terminal portion of the 5'untranslated region of its RNA 2 are known.