Christina DiFonzo

Christina DiFonzo is a Professor and Field Crops Entomologist at Michigan State University (MSU), primarily affiliated with the Saginaw Valley Research and Extension Center. She holds adjunct faculty positions at the University of Guelph and The Ohio State University. Her academic focus combines teaching (20%), research (15%), and extension activities (65%) in field crop entomology. DiFonzo earned her BS in Biology from Mercyhurst College (1987), followed by MS (1993) and PhD (1995) in Entomology from the University of Minnesota, with a focus on aphid-vectored viruses in potatoes. Postdoctoral work at Israel’s Volcani Center expanded her expertise in plant-virus-aphid interactions.

Her research addresses pest management in corn, soybean, dry beans, small grains, forage crops, sugar beets, and hemp. Key areas include soybean aphid biology, Bt resistance in corn, and neonicotinoid seed treatments. She maintains the influential Handy Bt Trait Table for U.S. corn production. Recent projects target Asiatic garden beetles, western bean cutworms, and stink bugs. DiFonzo teaches ENT 404: Fundamentals of Entomology and ENT 477: Pesticides in Management Systems, while advising ~15-20 graduate students annually across agronomy, weed science, and related fields.

Her extension efforts emphasize practical pest management strategies, including scouting protocols and resistance mitigation. Notable contributions include documenting soybean aphid emergence in North America (2002) and identifying aphid threats to industrial hemp. DiFonzo’s work bridges applied research, education, and agricultural extension, earning her the nickname “Aphid Queen.”