“Rootworm Damage to Bt Corn” has been making the headlines ever since word got out about research findings, documenting corn rootworm injury to Bt corn. Iowa State University (ISU) researchers published findings on July 29; the University of Illinois issued a press release Sept. 23.
Researchers say “growers should be careful not to jump to the conclusion that fields with severe rootworm injury are supporting a resistant western corn rootworm population.” In fact, university research data confirms that the real strategy for dealing with high corn rootworm pressure is to use rootworm-traited genetics in addition to other strategies. Additional management strategies against rootworm may include the return to the use of insecticides, crop rotation, changing which Bt trait is used from year to year and the use of hybrids that contain multiple traits for rootworm resistance (i.e. SmartStax).
These research findings suggest that improvements in resistance management and a more integrated approach to the use of Bt crops is necessary. Discovering resistance in a limited geography is a great reminder to “respect the refuge” and preserve the widespread use of the Cry3Bb1 protein. The Cry3Bb1 protein is found in many top-selling corn hybrids throughout the industry and remains an important component of a farmer’s corn rootworm strategy
Once thought to be a disease that only affected western states, Goss’s Wilt outbreaks have increased significantly in Iowa, Nebraska, Wisconsin and Illinois. The increased frequency has prompted many farmers to ask what they can do to avoid Goss’s Wilt in 2012.
Goss’ Wilt is a bacterium that can overwinter in infected residue on the soil surface and in weed hosts. Most often, the bacteria will enter the corn plant through wounds caused by hail damage, insects or even heavy winds. Since Goss’s Wilt is a bacterial disease, foliar fungicides have no effect. Therefore, in-season management options are very limited.
To avoid Goss’s Wilt in 2012, farmers should keep recommended management practices in mind. Best practices include growing resistant corn hybrids, using crop rotation and crop residue management. Choosing corn hybrids with a strong resistance to Goss’s Wilt is your first line of defense, Latham’s own John Toft was quoted in an article posted yesterday by Wallaces Farmer. Other tips to protect fields against Goss’s Wilt are detailed in that same article. Click here to read “Got Wilt? Keep Disease Resistance in Mind.”