Susceptibility of northern corn rootworm Diabrotica barberi (Coleoptera: Chrysomelidae) to mCry3A and eCry3.1Ab Bacillus thuringiensis proteins

Authors

Isaac O. Oyediran, Syngenta Crop Protection, LLC, Research Triangle Park, NCFollow
Phillip Matthews, Syngenta Crop Protection, LLC, Research Triangle Park, NC
Narendra Palekar, Syngenta Crop Protection, LLC, Research Triangle Park, NC
Wade French, USDA ARS, North Central Agricultural Research Laboratory, Brookings, SDFollow
Jared Conville, Syngenta Crop Protection, LLC, Research Triangle Park, NC
Tony Burd, Syngenta Crop Protection, LLC, Research Triangle Park, NC

Date of this Version

2015

Citation

Insect Science (2015) 0, 1–5

Comments

U.S. Government Work

Abstract

The susceptibility of the northern corn rootworm Diabrotica barberi (Smith & Lawrence) to mCry3A and eCry3.1Ab proteins derived from Bacillus thuringiensis (Bt) was determined using a diet bioassay. Northern corn rootworm neonates were exposed to different concentrations of mCry3A and eCry3.1Ab, incorporated into artificial diet. Larval mortality was evaluated after 7 d. The mCry3A and eCry3.1Ab proteins were found to be toxic to the northern corn rootworm larvae. The LC₅₀ and LC₉₉ values for mCry3A were 5.13 and 2482.31 μg/mL, respectively. For eCry3.1Ab, the LC₅₀ and LC₉₉ values were 0.49 and 213.01 μg/mL. Based on the estimated lethal concentrations, eCry3.1Ab protein was more efficacious to northern corn rootworm larvae than mCry3A. These lethal concentration values will be used as diagnostic doses for routine annual monitoring for change in susceptibility of field collected northern corn rootworm to mCry3A, and eCry3.1Ab toxins.