Neutralizing “Cousins” of the Irish Potato Famine Pathogen that Destroy Soybeans

Although oomycetes do not have household name recognition, this group contains hundreds of species that annually cause tens of billions of dollars in crop losses. A dramatic and historic example is Phytophthora infestans, which caused the Irish potato famine.

Today, another type of oomycete, Phytophthora sojae, is one of the most disruptive pathogens in soybean fields across the U.S. Large-scale funding from a USDA-NIFA Coordinated Activities Project grant and a soybean commodity group allowed a multi-disciplinary coalition of researchers from 19 universities to take on this challenge.

Our work is similar to counterespionage. We try to figure out the weapons that pathogens use and then turn those weapons against the pathogen or devise countermeasures.

– Dr. John McDowell

These scientists used information from P. sojae genomes to develop new diagnostic tools and to identify “Achilles heels” in the pathogen that can be exploited in new disease control strategies. The group identified new genes to work with in breeding disease-resistant soybeans. They also discovered the vast extent of a separate oomycete genus (Pythium) that has increasingly been troubling soybean farmers.

Preliminary estimates by agricultural economists suggest that these new tools could generate billions of dollars in savings on a global scale. Other impacts include an extension network that discussed oomycete diseases and control strategies with farmers and crop advisors, and an undergraduate education network that promoted the importance of agricultural bioinformatics for the next generation of U.S. researchers, producers, and policy makers.