Genetic basis of polyphagy in scale insects (Hemiptera: Coccoidea) explored via RNA-Seq

Scale insects are an appealing subject for studies of the genetics of host use for several reasons: (1) many species are economically destructive; (2) they include several of the most polyphagous species on earth; (3) because most species are entirely sessile throughout their adult lives, host records are uniquely reliable -- there are no "tourists"; and (4) because scale insects lack complex morphology and behavior, the causal connections between genome and ecology may be less complex than in many other insects.  Currently, little is known about the genetics of host use in scale insects. One possibility is that scale insects, like polyphagous Lepidoptera, express different detoxification genes on different hosts.  Using RNA-seq we plan to assess differential gene expression and identify genes responsible for polyphagy in scale insects. We sampled highly polyphagous scale insects from multiple host-plants and include replicated geographic sampling blocks in our sampling scheme.