Data from: Contemporary evolution of a Lepidopteran species, Heliothis virescens, in response to modern agricultural practices

Adaptation to human-induced environmental change has the potential to
profoundly influence the genomic architecture of affected species. This is
particularly true in agricultural ecosystems, where anthropogenic
selection pressure is strong. Heliothis virescens primarily feeds on
cotton in its larval stages and US populations have been declining since
the widespread planting of transgenic cotton, which endogenously expresses
proteins derived from Bacillus thuringiensis (Bt). No physiological
adaptation to Bt toxin has been found in the field, so adaptation in this
altered environment could involve: 1) shifts in host plant selection
mechanisms to avoid cotton, 2) changes in detoxification mechanisms
required for cotton-feeding versus feeding on other hosts, or 3) loss of
resistance to previously used management practices including insecticides.
Here we begin to address whether such changes occurred in H. virescens
populations between 1997-2012, as Bt cotton cultivation spread through the
agricultural landscape. For our study, we produced an H. virescens genome
assembly and used this in concert with a ddRAD-seq enabled genome scan to
identify loci with significant allele frequency changes over the 15 year
period. Genetic changes at a previously described H. virescens insecticide
target of selection were detectable in our genome scan, and increased our
confidence in this methodology. Additional loci were also detected as
being under selection, and we quantified the selection strength required
to elicit observed allele frequency changes at each locus. Potential
contributions of genes near loci under selection to adaptive phenotypes in
the H. virescens cotton system are discussed.