How to translate text using browser tools
27 April 2016 Field-Based Assessment of Resistance to Bt Corn by Western Corn Rootworm (Coleoptera: Chrysomelidae)
Ram B. Shrestha, Siva R. K. Jakka, B. Wade French, Aaron J. Gassmann
Author Affiliations +
Abstract

Western corn rootworm, Diabrotica virgifera virgifera LeConte, is a serious pest of corn and is managed with corn that produces insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt). Beginning in 2009, resistance to Cry3Bb1 corn, and severe injury to Cry3Bb1 corn in the field, was observed in Iowa. However, few data exist on how Cry3Bb1-resistant western corn rootworm interact with various management practices in the field. Using a field experiment, we measured adult emergence and feeding injury to corn roots for both Cry3Bb1-resistant and Cry3Bb1-susceptible populations of western corn rootworm when tested against various Bt corn hybrids and a soil-applied insecticide. Between 2012 and 2013, we evaluated five fields that were associated with greater than one node of feeding injury to Cry3Bb1 corn by western corn rootworm (i.e., problem-field populations), and a laboratory strain that had never been exposed to Bt corn (i.e., control population). Adult emergence for western corn rootworm and root injury to corn were significantly higher in problem-field populations than control populations for both Cry3Bb1 corn and mCry3A corn. By contrast, corn with Cry34/35Ab1, either alone or pyramided with Cry3Bb1, significantly reduced adult emergence and root injury in both problem fields and control fields. In problem fields, application of the soil-applied insecticide to Cry3Bb1 corn significantly reduced root injury, but not adult emergence. Our results are discussed in terms of developing strategies for managing western corn rootworm with resistance to Cry3Bb1 and mCry3A, and delaying the additional evolution of Bt resistance by this pest.

© The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com
Ram B. Shrestha, Siva R. K. Jakka, B. Wade French, and Aaron J. Gassmann "Field-Based Assessment of Resistance to Bt Corn by Western Corn Rootworm (Coleoptera: Chrysomelidae)," Journal of Economic Entomology 109(3), 1399-1409, (27 April 2016). https://doi.org/10.1093/jee/tow087
Received: 21 January 2016; Accepted: 29 March 2016; Published: 27 April 2016
JOURNAL ARTICLE
11 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

KEYWORDS
Bt corn
cross-resistance
Diabrotica virgifera virgifera
insect resistance management
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top