Joshua J Parsons

Area of Expertise: 
Insect Resistance Management
Masters in Seed Technology and Business

Josh completed a Masters in Seed Technology and Business while working full time at DuPont Pioneer. His project was a literature review  covering  cases of field-evolved resistance to Bt crops (corn and cotton). 

Benjamin D Brenizer

Area of Expertise: 
Crop pest management
Research Associate I

I worked in Dr. Gassmann's lab for three and a half years while obtaining my B.S. in Animal Ecology. I then spent a year as an intern at DM Crop Research Group, where I gained valuable experience in raising corn rootworm, raising fall armyworm, helping with soil sampling, collecting adult corn rootworm from tent studies, doing stand counts in corn and soybeans, and assisting with planting and harvesting of research plots. Currently I work in Dr. Gassmann's lab rearing corn rootworm for researching Bt resistance.

Stephen Thompson

Area of Expertise: 
Insect Resistance Management
M.S. in Entomology from Iowa State University

I am characterizing the genetics of western corn rootworm strains that have been selected for survival on maize expressing the Cry34/35Ab1 insecticidal proteins.  I also work full time for DuPont-Pioneer.

Dr. Jennifer Maxwell

Area of Expertise: 
Insect Resistance Management and Insect Pathology
Postdoctoral Research Associate

During her time as a postdoctoral scientist at Iowa State University, Dr. Maxwell studied a diversity of topics, including fitness costs of Bt resistance in western corn rootworm and European corn borer, tritrophic interactions among soil-borne entomopathogens, corn and western corn rootworm, and the application of integrated refuges and Bt pyramids to manage the evolution of resistance.

Patrick Weber

Agricultural Specialist III

I conduct field trials testing both commercial and pre-commercial products for management of insect pests of corn.  Much of my work focuses on western and northern corn rootworm, but I also have studied products targeting corn earworm, European corn borer, fall armyworm, seedcorn maggot and wireworm.  I conduct trials on Iowa State University Research farms and in farmers' fields.


Gressel, J., Gassmann, A. J., and Owen, M. D. K.  In Press.  How well will stacked transgenic pest/herbicide resistances delay pests from evolving resistance?  Pest Management Science.

Petzold-Maxwell, J. L., Siegfried, B. D., Hellmich, R. L., Abel, C. A., Coates, B. S., Spencer, T. A., Horikoshi, R. J. and Gassmann, A. J.  In Press.  Fitness costs associated with Cry1F resistance in the European corn borer.  Journal of Applied Entomology.  Read more about Publications

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