Soybean South


In-Crop Weed Control
Option Launched

With LibertyLink soybeans on the market this year, producers have the opportunity to rotate chemistries and prevent resistance to either Ignite or Roundup Ready.

By Carroll Smith

The introduction of LibertyLink soybeans marks two milestones. First, it means that Ignite herbicide is now labeled for use on all LibertyLink crops, including corn, cotton, canola and soybeans. Second, LibertyLink with Ignite herbicide provides a nonselective alternative to glyphosate-tolerant systems.

Arkansas weed specialist Ford Baldwin first worked with LibertyLink soybeans on an experimental basis in 1995 about the same time he was working with Roundup Ready soybeans in the same capacity.

“I saw the technologies were very similar,” Baldwin says. “They both provided broad spectrum over-the-top protection with excellent crop safety. The LibertyLink technology (in soybeans) didn’t come to the market at the same time as Roundup Ready, but it’s here now, and I think it is excellent complementary technology.

“LibertyLink provides control of resistant weeds and is a good prevention program,” he adds. “The best way to manage resistance is never to get it. It also controls some weed species, especially those we have in the Mid-South, such as smartweed, morningglory and coffeebean. Ignite is very hot on these problem weeds and offers the same broad spectrum over-the-top efficiency.”

Baldwin worked with the LibertyLink/Ignite system in 30 seed fields (4.9 maturity variety) in Arkansas in 2008. He says it was a tough year, including drought problems that made it hard to make timely applications.

“However, in all 30 fields, which were planted behind wheat, we had excellent control with Ignite, and none of the fields cut under 40 bushels. Most of them cut in the 45- to 55-bushel range,” he adds.

Weed resistance considerations
Baldwin says there are two ways to look at weed resistance – after you already have it and before it shows up in your fields.

“We’ve done an excellent job in Arkansas in the field and in research plots in controlling some of the resistant weeds like Palmer pigweed, which is a big issue for us,” he says. “But the bigger consideration is prevention. Every farmer has to deal with herbicide resistance whether it’s through fighting it or trying to prevent it.

“LibertyLink technology offers an opportunity for the farmers who don’t yet have it,” Baldwin notes. “It’s not a matter of if, it’s a matter of when if you keep using the same technology over and over. Now we have an opportunity to rotate the same efficiency in weed control and, by rotating, we can prevent resistance to either Ignite or Roundup Ready.”

Availability in 2009
Andy Hurst, product manager, herbicide-tolerant traits and Ignite herbicide, Bayer CropScience, says LibertyLink soybean varieties will be sold by more than 85 seed companies in 2009.

“We expect seed stock to accommodate about 1 million acres this year with relative maturity ranges from .5 to 4.9,” Hurst says. “The available mid-3 to 4.9 maturity range will probably be the best fit for the Southern end of the soybean production areas. However, we anticipate quickly having varieties in later maturities in 2010 and beyond.”

A Quick Look At LibertyLink Soybeans

• The LibertyLink (LL) trait will be launched in 2009.

• LL varieties are high-yielding with no yield drag or lag.

• LL soybeans combine high-yielding genetics with a built-in tolerance to Ignite, a nonselective, postemergent herbicide.

• Ignite and the LL trait allow producers to rotate nonselective herbicides to manage weed resistance and preserve the utility of herbicide-tolerant technologies.

• The LL trait will be broadly licensed to multiple leading seed companies.

• To learn more, visit

Source: Bayer CropScience.