Location: Great Basin Rangelands ResearchTitle: Wheat curl mite, a global pest of cereals, is a complex of biotypes with divergent host ranges and variable pest potential Author
Submitted to: Biological Journal of the Linnean Society, London
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/16/2012
Publication Date: 2/1/2013
Citation: Skoracka, A., Szydio, W., Rector, B.G., Kuczynski, L. 2013. Wheat curl mite, a global pest of cereals, is a complex of biotypes with divergent host ranges and variable pest potential. Biological Journal of the Linnean Society, London. 109:165-180. Interpretive Summary: The wheat curl mite (Aceria tosichella) is a global pest of wheat and other cereals, causing losses by direct damage as well as transmission of plant pathogens such as wheat streak mosaic virus. This mite has traditionally been considered as a single species capable of attacking >80 different plant species. Through comparison of genetic sequence variation between different populations of A. tosichella and host-range bioassays on these populations, this study revealed a broad range of host acceptance among genetically distinct A. tosichella populations, from generalist feeding to high host-specificity. In addition to providing useful information that contributes to management strategies against this pest, these results have implications on the study of this mite’s taxonomy and invasiveness, as well as the genetics underlying host-specificity in arthropods.
Technical Abstract: Background. The wheat curl mite (Aceria tosichella) is a global pest of wheat and other cereals, causing losses by direct damage as well as transmission of plant pathogens such as wheat streak mosaic virus. This mite has long been considered to be a single, highly polyphagous species, capable of colonizing >80 plant species. The purpose of this study was to examine genetic and host-acceptance variation in field-collected populations of A. tosichella to test the assumption that it is a single, highly polyphagous species. Methodology/Principal Findings. Populations of A. tosichella were collected from five different grass hosts in Poland and maintained as laboratory colonies on the same five hosts. DNA was extracted from individual mites for sequencing of a mitochondrial cytochrome c oxidase I (COI) gene fragment and subsequent Neighbor Joining and Maximum Likelihood analyses. Host acceptance was tested by transferring mites from their source hosts to other plant species recorded as hosts of A. tosichella and measuring mites’ population growth rate. Thirteen different COI haplotypes were detected from 249 A. tosichella individuals and grouped into seven related lineages. Sequence divergences between lineages suggested reproductive isolation and in some cases species-level variation. Host-transfer experiments revealed significant differences in host ranges between lineages, ranging from highly polyphagous to host-specific. Conclusions/Significance. The results of these experiments have implications for the taxonomy, DNA bar coding, management, invasiveness, and disease transmission capability of wheat curl mite, as well as for the mode of inheritance of host-acceptance traits in Eriophyidae and the suitability of mites as biological control agents of invasive grass species.