Manage Risk with a Trait Rotation Strategy

July 27, 2012 10:01 PM

This multiyear approach can help you prevent resistance

Familiarity might breed contempt, but diversity delights. Today, corn producers can take delight in the fact that they have access to 13 separate events (traits) that are stacked in various combinations in corn hybrids.
But because most individual events appear in multiple-trait stacks, farmers could be planting hybrids with the same event year after year and not even realize it. Here’s one example. You go with a Monsanto Genuity SmartStax hybrid the first year, a Dow AgroSciences SmartStax hybrid the second year, and then a Monsanto Genuity VT Triple PRO hybrid the third year. In this scenario, you used the Mon88017 event three consecutive times.
Christian Krupke, Purdue University associate professor and Extension entomologist, says the newer multistack hybrids might help reduce a farmer’s need to rotate traits. However, he says, there are pockets of acres where it would be wise to adopt a rotation strategy.
"Certainly in fields where resistance has popped up, or in continuous corn with a continuous use of the same Bt action, trait rotation would be a good idea," he says.

Trust your gut. Krupke’s bottom-line advice is the same, no matter what an individual farmer’s production practices are in his fields.
"The No. 1 thing is vigilance," he says. "Be aware that resistance to Bt corn could happen in your area, especially if you have some of the key risk factors we have seen in problem fields throughout the Midwest: a history of continuous corn using the same Bt toxin. If you think there are performance problems, follow up on it. Don’t dismiss it—trust your instincts."
There are many trait choices in today’s marketplace—more than ever before, says Luke Samuel, Monsanto corn insect traits product manager. But the choice is becoming easier
because Monsanto and other major hybrid providers are sorting their products into distinct trait "platforms," he adds.
Using the Genuity lineup as an example, Samuel says a farmer faced with the greatest insect and weed pressure could look into hybrids containing the Genuity SmartStax trait platform, with three aboveground and two belowground modes of action for insect feeding, plus two herbicide tolerance traits. Fields with lesser insect pressure may fare better with a
Genuity VT Triple PRO (two above, two below, one herbicide) or Genuity VT Double PRO (two above, one herbicide) hybrid instead.
"Based on what type of insect pressure you have, the trait package can be a pretty big selection factor," Samuel says. "The overall decision of which hybrids fit best in your fields adds to the complexity, but farmers have great choices. It’s a good situation when they have the choice to pick top hybrids with different insect and weed protection packages."
Farmers have to make good decisions every day to be successful, Samuel says. By fine-tuning trait selections and rotations, they have another opportunity to boost their returns.

Follow the rules. Herbicide traits are a bit trickier to manage because farmers not only have to choose the traits themselves, but also how to manage the corresponding herbicide(s). Farmers should "always read and follow label instructions," as all of the crop chemical companies urge. One big example: When a corn hybrid or soybean variety contains both LibertyLink and Roundup traits, it may be tempting to simply tank-mix Liberty and Roundup herbicides. However, a much more effective solution is to make an initial application of Liberty herbicide, followed by a later application of Roundup.
As additional herbicide traits come to market, premix herbicide solutions make the decision-making process a bit easier. Dow AgroSciences’ Enlist weed control system, pending regulatory approval, will give farmers access to Enlist Duo, a premix of 2,4-D choline and glyphosate, as early as 2013. Following close behind is a collaboration between BASF and Monsanto on dicamba-resistant soybeans and proprietary new dicamba herbicide formulations, which could debut in farmers’ fields as early as 2014.
Damon Palmer, U.S. commercial leader for Enlist, says farmers should look at herbicide traits as just one piece of a larger weed management puzzle they need to solve.
"Traits should definitely be part of the consideration set, but you have to look at all of the options that are associated with that trait," he says. "Use multiple modes of action. Proper rates and application timings are also very important."
Agribusinesses are becoming increasingly candid about the need to educate farmers on the best management practices that will prolong the shelf life of these new traits. They also are cooperating with other companies on the control strategies farmers put in place. In some instances, that even means recommending a competitive company’s product to create additional diversity that will further protect a trait’s viability for the future.
"We want farmers to be proactive," Palmer says. "You may not be seeing resistance on your farm, but don’t wait until you do. We want to maintain both the traits we have today and the ones being developed in the future."

Know Your Export Options

With so much of the U.S. corn crop exported, it’s important to take note of which events your hybrids include. Not all hybrids are approved for export market use, especially in the European Union (EU). Because of that, the National Corn Growers Association (NCGA) has made it a
priority to publicize regular updates on the approval status of these events. NCGA also encourages farmers to read their grower agreements before planting and communicate openly with their grain buyers.
NCGA recommends that any hybrids not fully approved for EU export be funneled into one of three markets:

  • A farmer’s own livestock rations
  • Domestic livestock feeding channels
  • Elevators that accept grain not fully approved for EU export

For more information, visit

Back to news



Spell Check

No comments have been posted to this News Article

Corn College TV Education Series


Get nearly 8 hours of educational video with Farm Journal's top agronomists. Produced in the field and neatly organized by topic, from spring prep to post-harvest. Order now!


Market Data provided by
Brought to you by Beyer