|Mcmechan, Anthony -|
|Hein, Gary -|
Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 21, 2013
Publication Date: May 10, 2014
Repository URL: http://handle.nal.usda.gov/10113/58897
Citation: Mcmechan, A.J., Tatineni, S., French, R.C., Hein, G.L. 2014. Differential transmission of Triticum mosaic virus by wheat curl mite populations collected in the Great Plains. Plant Disease. 98:806-810. Interpretive Summary: Triticum mosaic virus (TriMV) is a recently reported virus in the Great Plains region with limited knowledge on its spread in wheat fields. In this study, we examined TriMV transmission by three wheat curl mite (WCM) biotypes found in the Great Plains region: Nebraska (NE), South Dakota (SD) and Montana (MT). Interestingly, in single-mite transfer experiments, only the NE biotype mites efficiently transmitted TriMV, but the SD and MT biotype WCMs failed to transmit. In multi-mite transfer experiments, the NE biotype mites transmitted TriMV at 100%, while the SD and MT biotype mites transmitted only at 2.5%. Additionally, we found that the nymphs of NE biotype mites could acquire the virus and maintained through the molting process, suggesting that TriMV may be transmitted in a semi-persistent manner. Differential transmission of TriMV by different WCM biotypes suggests that presence of a particular mite biotype in a field would affect TriMV disease epidemiology.
Technical Abstract: Wheat is an important food grain worldwide, and the primary dryland crop in the western Great Plains. A complex of three wheat curl mite (WCM)-transmitted viruses [Wheat streak mosaic, High plains, and Triticum mosaic viruses (TriMV)] is a cause of serious loss in winter wheat production in the Great Plains. TriMV was first reported in Kansas in 2006, and later found in most other Great Plains states. Currently, three populations of WCM have been identified by genetic characterization and differential responses to mite resistant genes in wheat. In this study, we examined TriMV transmission by three identified WCM populations: Nebraska (NE), Montana (MT), and South Dakota (SD). Mite transmission using single-mite transfers revealed that the NE WCM population transmitted TriMV at 41%, while the MT and SD WCM populations failed to transmit TriMV. In multi-mite transfers, the NE WCM population transmitted TriMV at 100% level compared to 2.5% transmission by MT and SD WCM populations. Interestingly, NE mites transferred during the quiescent stages following the 1st and 2nd instar transmitted TriMV at 35-38%, suggesting that nymphs were able to acquire the virus and maintain it through molting. The ability of WCM to transmit TriMV after molting suggests that this virus may be transmitted in a semi-persistent manner.