Gassmann, Aaron

Profile Picture
Email Address
aaronjg@iastate.edu
Birth Date
Title
Professor
Academic or Administrative Unit
Organizational Unit
Entomology

The Department of Entomology seeks to teach the study of insects, their life-cycles, and the practicalities in dealing with them, for use in the fields of business, industry, education, and public health. The study of entomology can be applied towards evolution and ecological sciences, and insects’ relationships with other organisms & humans, or towards an agricultural or horticultural focus, focusing more on pest-control and management.

History
The Department of Entomology was founded in 1975 as a result of the division of the Department of Zoology and Entomology.

Related Units

About
ORCID iD

Search Results

Now showing 1 - 2 of 2
No Thumbnail Available
Publication

Tritrophic interactions among Bt maize, an insect pest and entomopathogens: effects on development and survival of western corn rootworm

2012-01-01 , Petzold-Maxwell, Jennifer , Jaronski, Stefan , Gassmann, Aaron , Entomology

Agricultural systems often provide a model for testing ecological hypotheses, while ecological theory can enable more effective pest management. One of the best examples of this is the interaction between host-plant resistance and natural enemies. With the advent of crops that are genetically modified to produce insecticidal toxins from the bacterium Bacillus thuringiensis (Bt), a new form of host-plant resistance has been introduced to agroecosystems. How Bt crops interact with natural enemies, especially insect pathogens in below-ground systems, is not well understood, but provides a unique opportunity to study below-ground tritrophic interactions. In this study, we used two species of entomopathogenic fungi and three species of entomopathogenic nematodes to determine how this community of soil-borne natural enemies might interact with Bt maize (event 59122, expressing the insecticidal protein Cry34/35Ab1) to affect survival and development of western corn rootworm (Diabrotica virgifera virgifera), which is an obligate root feeder and a serious pest of maize. We ran two experiments, one in a greenhouse and one in a growth chamber. Both experiments consisted of a fully crossed design with two maize treatments (Bt maize and non-Bt maize) and two entomopathogen treatments (present or absent). The community of entomopathogens significantly increased mortality of western corn rootworm, and Bt maize increased larval developmental time and mortality. Entomopathogens and Bt maize acted in an independent and additive manner, with both factors increasing the mortality of western corn rootworm. Results from this study suggest that entomopathogens may complement host-plant resistance from Bt crops.

No Thumbnail Available
Publication

Rootworm Management with Genetically Modified Corn: Current Status, Potential for Resistance, and a Look Toward the Future

2009-01-01 , Hibbard, Bruce , Sappington, Thomas , Miller, Nicholas , Gassmann, Aaron , Entomology

The western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte) is one of the most serious crop pests in North America and Europe. WCR feeding causes reduced water and mineral uptake. Yield loss is most severe when water is limiting. Grain from damaged plants is also more likely to be left in the field due to increased lodging of plants with reduced brace root support. WCR are univoltine, with eggs overwintering in the soil. There are three larval instars, with the bulk of the damage being caused by third instar.