Michael Smith (Entomology), John Reese (Entomology),
Joyti Shah (Biology) and Gerald Reeck (Biochemistry) study aphids (Russian wheat aphid, Diuraphis noxia; greenbug, Schizaphis graminum; green peach aphid, Myzus persicae; soybean aphid, Aphis glycines; and pea aphid, Acrythosiphon pisum) of major global agronomic importance. For example, D. noxia and S. graminum cause ~ $1 billion in annual losses to U. S. barley, sorghum and wheat production alone. Although considerable progress has been made in the identification of wheat genes involved in D. noxia resistance, knowledge of aphid responses to plants lags, and efforts are underway to develop microarrays of virulence genes used by some strains of these aphids to overcome plant resistance genes. Initial studies with D. noxia indicate that many genes encoding detoxification, proteolysis, and lipid synthesis among others, are unsuccessful in D. noxia attempts to overcome the effects of plant resistance. However, genomic studies by Reeck’s group have detected a unique A. pisum salivary gland protein with a significant role in aphid feeding.
A publication now in press in the Journal of Insect
Science describes the silencing of that transcript,
and its essentiality to the aphid. Efforts to develop aphid microarrays will be facilitated by EST libraries being constructed for A. pisum and M. persicae by collaborators in Chile, France and Spain, and the current genome sequencing of the pea aphid.