Seifers, D.L., Kansas State University, Agricultural Research Center, Hays, KS 67601-9228, United States
Harvey, T.L., Department of Entomology, Kansas State University, Manhattan 66506, United States
Martin, T.J., Kansas State University, Agricultural Research Center, Hays, United States
Haber, S., Cereal Research Center, Agriculture and Agri-Food Canada, 195 Dafoe Road, Winnipeg, Man., Canada
She, Y.-M., Department of Physics and Astronomy, University of Manitoba, Winnipeg, Man., Canada
Ens, W., Department of Physics and Astronomy, University of Manitoba, Winnipeg, Man., Canada
Standing, K.G., Department of Physics and Astronomy, University of Manitoba, Winnipeg, Man., Canada
Salomon, R., Volcani Center, Bet-Dagan, Israel
Gera, A., Volcani Center, Bet-Dagan, Israel

Wheat with yellow head disease (YHD) (yellow heads and mosaic leaf symptoms) has been observed in Kansas since 1997. A pathogen was transmitted from the infected wheat to maize by vascular puncture inoculation and to Nicotiana benthamiana by rub inoculation. The original infected wheat and infected maize and N. benthamiana test plants all produced a unique 32- to 34-kDa protein when analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Time-of-flight mass spectrometry analysis of the unique 32- to 34-kDa protein showed that the amino acid sequence was most closely related to the nucleoprotein of Rice hoja blanca virus, indicating that the virus causing YHD symptoms in wheat is a tenuivirus. Antiserum made to this protein failed to react with extracts made from healthy wheat or wheat infected with Wheat streak mosaic virus or the High Plains virus. The antiserum did react to extracts made from symptomatic wheat, maize, and N. benthamiana, shown by SDS-PAGE to contain the unique protein, and to extracts of wheat with YHD symptoms from Kansas, North Dakota, South Dakota, and Oklahoma. The name Wheat yellow head virus is proposed for this virus. © 2005 The American Phytopathological Society.