EAST LANSING, Mich. — The Handy Bt Trait Table has been updated as of May 2019, as well as an updated list of citations for Bt resistance. The reason for the update is explained on Page 1 of the publication. On Page 2, the table itself, there are changes that reflect two more findings of Bt resistance.
- European corn borer resistance was found to single-trait Cry1F Bt hybrids in Canada. Thus, “ECB” was added to the resistance column for each trait package that has Cry1F alone. I would appreciate feedback about using single-trait Bt hybrids in Michigan. I hope they are not being sold or planted, but I honestly don’t know.
- Bt resistant NORTHERN corn rootworm populations were confirmed in North Dakota. Resistant populations of Western corn rootworms (the species with the black stripes) already have been found to all types of Bt. There were even a few field failures in Michigan in 2011-2012. This is the first time that Bt resistant Northerns have been found. Although westerns are the most common species in Michigan fields, I sometimes do see fields full of northerns. In the trait table, I now separate out these species as WCR and NCR.
Access the updated for 2019 table at: Handy Bt Trait Table for U.S. Corn Production.
— Christina DiFonzo, Michigan State University Extension, Department of Entomology
For more news from Michigan, click here.