Effects of Nematode Genetic Diversity on Management of Potato Pests
CSANR Project 104
Market forces are driving conventional Columbia Basin potato growers towards less-chemically-intensive pest management approaches, such as biological control. Insect-killing, entomopathogenic nematodes (EPNs), which live in the soil, have great potential for controlling insects with belowground life stages — such as the Colorado potato beetle. Our initial results suggest that EPNs can be incredibly abundant in WA potato fields where pesticide use is reduced, for example under organic management. We now know that two species, Heterorhabditis bacteriophera and Steinernema feltiae, dominate these EPN communities. However, the taxonomy of these nematodes is poorly understood, and our preliminary experiments suggest that genetic diversity within EPN species is as important for strong potato beetle control as is diversity at the species level. Here, we propose to combine a comprehensive collection of EPN strains from WA potato fields with cutting-edge genomics approaches for describing genetic diversity among these strains. Critically, field experiments will be used to relate genetic diversity within EPNs to the ability of these nematodes to control potato beetle pests in regions with varying climatic conditions. Our research will address two of the main 2012 priorities of the BioAg program, “Biological intensive and organic approaches to sustainable management of pests” and “Innovation and diversification to increase the resiliency and sustainability of farming and food systems in the face of climate change.” More fundamentally, we are fostering the development of the emerging field of “ecological genomics”, wherein the tools of modern molecular biology are used to understand the community ecology of natural pest control.