Pressure mounts on farmers everywhere to plant more triple-stack hybrids next year. Typically, that means they're getting corn borer protection and rootworm protection in the plant, plus herbicide tolerance to either glyphosate (Roundup-type product) or glufosinate (Ignite). Ignite replaced Liberty on the market.
Part of the pressure comes from reports from many farmers who say triple stacks performed better this year. In fact, nearly every farmer in every combine cab we visited with this fall praised triple stacks, with yield advantages running 15 to 25 bushels per acre. Are they comparing triple stacks with the genetically equivalent isoline (identical hybrids) used for refuge acres? Even if they are it's expected that triple stacks will show up well.
Despite all the optimism for triple stacks this season, Dave Nanda still believes farmers should evaluate their situation case by case. Consultant for Corn Illustrated, Nanda is also President of Bird Hybrids LLS., a small seed company based in Tiffin, Ohio in the Eastern Corn Belt. Nanda's company also sells triple stacks, along with a line-up of hybrids with different combinations of traits, a single trait or no traits.
Genetics is still the key factor, Nanda stresses. The base genetics of the hybrid must yield well on your farm. Otherwise, all the traits added to it won't matter. Traits don't add yield by themselves, he insists. Instead, the idea of traits available on the market so far protects the inherent genetic potential of the plants. In the absence of the pest they're designed to protect against, whether it's an insect or weeds, the trait itself doesn't have the power to add extra bushels per acre. It's when corn borers threaten, as often happens in the western Corn Belt, or when northern corn rootworms are thick enough to create havoc, which can be the case in certain parts of the Eastern Corn Belt, that the traits offer protection that helps plants fend off these pests. The results in those cases are often healthier plants, simply because they have not been attacked by the pests.
Nanda especially likes to make sure farmers understand the truth about root mass. Just because a hybrid is a triple stack doesn't mean it automatically will have a bigger root mass, he insists. The quantity of roots generally relates back to the genetic make-up of the hybrid. Some hybrids are from corn lines that put out bigger root systems or that root better in general than other lines. That fact has nothing to do with whether there are traits also in the hybrid or not.
If a triple-stack doesn't have as good a genetic package with high-yield potential as a non-GMO hybrid without traits, it won't out-yield it under normal conditions, the plant breeder says. If insects that the traits protect against are present in large numbers and cause significant damage to corn that's not properly protected, then the triple stack hybrid could yield more, even if its genetic make-up isn't as good as a non-traited hybrid.
Since triple stacks are more expensive, some farmers believe they're also automatically best against diseases. However, triple stacks give tolerance to herbicides and targeted insects only. That has nothing to do per se with tolerance to rust, northern leaf blight, southern leaf blight, Anthracnose, Diplodia and Gibberella ear and stalk rots. Resistance to these pathogens must be in the non-traited, base genetics of the hybrid.
Nanda wants to make sure farmers realize what they're paying for. If they don't need to spray most fields most years, then paying for glyphosate tolerance may not be the most economical move, he observes. Many hybrids come with tolerance to Ignite built in, due to the way the hybrid was developed during the breeding process. So in most cases, there is no extra charge for Ignite tolerance. Nanda believes that in cases where you're not sure if you will need to spray a broad spectrum herbicide over the top, you could save money on seed costs by going with a product where the trait (Ignite tolerance) is included at no extra cost.
Those are the types of decisions farmers need to think through instead of just opting for triple stacks automatically, he insists.