Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: June 1, 2005
Publication Date: June 1, 2005
Citation: Robertson, N.L., French, R.C. 2005. Unique barley yellow dwarf virus-mav-like serotypes in Alaska. Phytopathology. Vol 95(6):S89. Technical Abstract: Barley yellow dwarf (BYD) disease in barley and oats in Alaska was confirmed to be due to Barley yellow dwarf virus-PAV and Cereal yellow dwarf virus-RPV using serology and sequencing RT-PCR products. In 2003, however, 40 plants in an oat field that exhibited symptoms of red leaves typical for BYD were all serologically negative for BYDV-PAV, -MAV, -SGV, and CYDV-RPV by ELISA assays. Only one plant produced a RT-PCR product using standard “universal luteovirus” primers, Lu1 and Lu4. Sequence data revealed that it was a PAV-like isolate. The same 40 plants were re-assayed using new primer sets (Yan-R and Shu-F, or Yan-R and MAV2-F) described by Malmstrom and Shu (J. Virol. Methods 120:69-78), resulting in RT- PCR products of predicted sizes for over half of these. DNA sequences of these were found to be most similar to BYDV-MAV isolates by a NCBI Blast search. The Alaskan MAV-like isolate coat protein gene sequences differed in several regions that otherwise are conserved among other MAV isolates. Specific differences in one or more of these regions may determine serological variation among MAV-isolates, and could account for negative ELISA assay results with the Alaskan MAV-like isolates. This is the first report of BYDV-MAV in Alaska.