8: Genomic innovations for exploiting stored commodities

Stored product insects cause millions of dollars in losses to grains during storage and can even damage products that have been processed and packaged for sale to consumers.  Many of these insects can chew through plastic and other packaging materials, while others have evolved resistance to pesticides and fumigants or can withstand extreme environmental conditions.  Collectively, these characteristics make it exceptionally difficult to manage these pests.  Stored product insects are taxonomically diverse and occupy a unique ecological niche.  The ability to exploit stored grains has evolved independently in many evolutionarily distinct insect lineages and many of these species feed on the same grains and respond to the same volatiles emitted from food sources.  Despite their common niches, the genetic mechanisms underlying their ability to locate and exploit these food sources have not been characterized.  Through the AgPest100 initiative, the genomes of stored product insects from five different taxonomic families were sequenced using long-read PacBio sequencing from single individual insects, allowing us to obtain more accurate assemblies of highly heterozygous regions of the genome and areas that consist of tandem arrays of multicopy gene families.  In many cases, assemblies were scaffolded to chromosome scale using HiC-based approaches.  Using these resources, we are now exploring the evolutionary history of digestive and chemosensory genes to determine whether there are any convergent genomic strategies for exploiting stored commodities across these insect lineages.