Evaluating Non-Target Effects of Rootworm Maize (Cry34/35ab1) on Carabid Beetles
Corn Insects and Crop Genetics Research
2012 Annual Report
1a.Objectives (from AD-416):
1) Determine whether Cry34/35Ab1 rootworm Bt corn significantly affects the abundance and diversity of carabid beetle populations;.
2)Determine whether insecticide treated soil significantly affects the abundance and diversity of carabid beetle populations;.
3)Assess the magnitude of the effects of Cry34/35Ab1 Bt corn on carabid beetles relative to the effects of soil insecticides.
1b.Approach (from AD-416):
A two year study will investigate possible effects of rootworm Bacillus thuringiensis (Bt)(Cry34/35Ab1) corn on carabid beetles. Corn hybrids will include Roundup Ready Cry34/35Ab1 corn, known as Herculex (R) RW [HR-RW], and a non-Bt near isoline [NBt-Iso]. Insecticides would include seed treatments Poncho 1250, Cruiser 250, and tefluthrin applied once at planting. The following treatments will be arranged in a RCB and replicated four times: .
1)HR-RW (no insecticide);.
2)NBt-Iso (check, no insecticide);.
3)HR-RW with Poncho 1250;.
4)NBt-Iso with Poncho 1250;.
5)HR-RW with Cruiser 250 + tefluthrin; and.
6)NBt-Iso with Cruiser 250 + tefluthrin. Pitfall traps will be used to sample beetles ten times over each growing season.
Two years of field tests have been completed to determine possible non-target effects of maize with resistance to rootworm (Bacillus thuringiensis binary proteins Cry34Ab1/Cry35Ab1) on ground beetles. Processing of the pitfall traps continues. A progress report was provided to the cooperator. The project is related to the objective “Determine the nature and degree of potential impacts of transgenic corn on non-target organisms” of the in-house project (3625-22000-017-00D).