Wheat curl mite interactions with wheat and wheat viruses

The wheat curl mite, Aceria tosichella Keifer, transmits three viruses to wheat, wheat streak mosaic virus (WSMV), high plains virus (HPV), and Triticum mosaic virus (TriMV) to wheat (Triticum aestivum L.) throughout the Great Plains.  This virus complex creates serious disease problems in winter wheat in the western Great Plains.  Mite and virus resistance in wheat and cultural practices have constituted management of this virus complex.  Complications from biotypic variability and, more recently, interaction of other biological and ecological factors have impacted the effectiveness of management.  One important factor in these interactions relates to the identity of the wheat curl mite.  A. tosichella has a long history of serious taxonomic confusion.  Molecular techniques have recently been used to characterize multiple A. tosichella populations.  DNA from these populations was PCR amplified and regions of both ribosomal (ITS2) and mitochondrial genes sequenced.  Considerable separation between mite populations was found and these differences relate to biological differences (e.g. biotypic and virus transmission).  These differences underscore the importance of identifying mite populations in studies where interactions with mite types may occur.