I recently participated in a tour to look at much of the work the University of Arkansas is conducting on LibertyLink soybeans and to get an update from Bayer CropScience on the status of the introduction of the LibertyLink/Ignite herbicide technology.
As a weed scientist, I am excited about this technology. We have had no new herbicide technology introduced in soybeans since the Roundup Ready technology became commercially available well over 10 years ago. Roundup Ready technology changed our entire crop production system to one that is far more efficient than what we had prior.
I have written on many occasions, however, that while weed control technology is at a standstill, the weeds are not. I believe Palmer pigweed resistance to glyphosate made its big move this year. If this is true, resistance pigweed will be common, starting next year.
On this tour I heard one University of Arkansas weed scientist and one University of Tennessee weed scientist tell the group that glyphosate could no longer be considered a pigweed herbicide in those states. To a farmer or a person who works directly with farmers, those statements spoke volumes. Palmer pigweed is only one example of glyphosate resistance, but it the one I believe will have the most profound impact the quickest.
I have attended several roundtable discussions and “think tank” meetings in recent years on how to deal with glyphosate resistance issues. Many of the answers proposed included the use of residual herbicides and the uses of tank mixes in a Roundup Ready system.
While these can help, they are essentially the same herbicides that were not controlling Palmer pigweed before Roundup Ready. Unless there are some real breakthroughs in novel herbicide chemistry, the breakthroughs are going to come in the form of traits.
The LibertyLink soybean trait has been around a long time. I first worked with it along with my research counterpart, Dick Oliver, at the University of Arkansas in 1995, but after a couple of years the development was suspended. At that time we were making direct comparisons between Ignite-tolerant soybean weed control programs (as they were called then) and Roundup Ready soybean weed control programs. It was evident both herbicide systems could have a huge impact.
Glyphosate (Roundup) and glufosinate (Ignite) are similar but different herbicides. Both are broad spectrum, non-selective herbicides. Glyphosate, however, is readily translocated in plants whereas glufosinate behaves much more as a contact herbicide.
When available, LibertyLink soybeans will provide a much better option for controlling glyphosate-resistant weeds. In a bigger picture it represents a resistance management option we have not had.
A much better alternative to fighting glyphosate-resistant weeds is to implement a whole-farm resistance management program to never get glyphosate resistance to begin with.
The LibertyLink system offers another broad spectrum over-the-top herbicide option to rotate with the Roundup Ready system. In addition, Ignite is much better on some weeds, such as the morningglories, hemp sesbania, smartweed and even yellow nutsedge than glyphosate.
Likewise, glyphosate is better on some weeds than Ignite. Because of this, there can be a real advantage to be able to rotate these systems.
It was obvious from this tour and meeting, the technology is much closer to reality than some realize. Seed are being increased this year for a 2009 launch. The Bayer CropScience representatives announced export clearances for China. Clearances are expected soon in the EU.
I believe the LibertyLink technology is the first step in what we will see coming in terms of traits to make weed control much easier. The weeds are changing and so must technology.
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