The Future of Weed Control

What’s next in the herbicide innovation pipeline?

It’s been 21 years since Roundup Ready® soybean varieties were introduced to the marketplace. LibertyLink® soybeans have been commercially available for close to 20 years. But a lot has changed since then.

Farming technologies and seed innovations continue to advance and evolve. So what’s next?

Here’s a snapshot of what’s coming:

  • Balance™ GT Soybean: A double stacked trait option with glyphosate and isoxaflutole tolerance
  • Enlist E3 Soybean: A molecular stack with glyphosate, 2,4-D, and glufosinate tolerance
  • MGI Soybean: Will allow use of mesotrione and isoxaflutole in combination of glufosinate (Liberty)
  • Protoporphyrinogen Oxidase (PPO) Soybean: Will allow over-the-top PPO herbicide applications
  • RNA interference (RNAi) technology

Stacked Trait Options and Technologies in the Pipeline

As of summer 2017, the only commercially available stacked trait on the market is the Roundup Ready 2 Xtend soybean. But Jason Norsworthy, Ph.D., weed scientist at the University of Arkansas, says there are several new technologies on the horizon.

“The Balance GT soybean recently received import approval in China, but is still waiting on a federal label for the Balance herbicide,” says Norsworthy.

Norsworthy also says that Dow AgroSciences’ Enlist Duo® herbicide is registered, but Enlist soybeans are pending import approval. “The Enlist soybean trait has not been approved in China, so Dow has elected not to bring it forward commercially until Chinese approval is received.”

Traits that have not yet entered the conversation include the MGI soybean, which is a trait Bayer Crop Science and Syngenta are working on jointly, says Norsworthy. “In terms of this being commercially available, it’ll likely be 2021 or 2022.”

Looking beyond that, Protoporphyrinogen Oxidase (PPO) resistance is another trait farmers can use in the future, although it likely won’t be until 2024. “This trait will allow for some pretty strong PPO herbicides, some that we typically can’t spray today over-the-top of soybean.”

According to Norsworthy, if you wanted to look outside of traits, the next innovation in the pipeline would be Monsanto’s RNA interference (RNAi) technology.

None of these expected new soybean traits will be the be-all end-all for herbicide resistance management challenges, but they will likely prove to be valuable tools for farmers to use as part of a diversified weed management strategy.

Non-Chemical Weed Control Options

The key to managing resistance is diversity.

“We underutilize some non-chemical tactics that we have,” says Norsworthy.

While waiting for the next herbicide technology to become commercially available, there are non-chemical practices you can take advantage of now to help combat weeds.

For example, generally, weeds do not emerge when you have crop canopy formation. Norsworthy points to research that shows when crops achieve 90 percent canopy formation, most weeds will cease to emerge.

“Any attempt to narrow row spacing and increase the rate of crop canopy formation will take pressure off herbicides and reduce the length of time you’ve got to rely on herbicides,” he says.

Some new non-chemical technologies being used and tested in Australia are the Integrated Harrington Seed Destructor (iHSD) and the Seed Terminator. These machines destroy weed seed as it exits the combine.

Even though they aren’t currently able in the U.S., Norsworthy was able to get his hands on a stationary iHSD.

“When conducting research on Palmer amaranth and waterhemp, we found a large percentage of the seed is retained on the plant, goes into the combine, cleaned from the seed and then is returned back to the field,” says Norsworthy. “Why not destroy the weed seed in the combine with something like the iHSD, instead of sending it back into the field?”

The Integrated Harrington Seed Destructor and Seed Terminator are both in use in Australia. Norsworthy expects production to increase and for this technology to be in the U.S. within the next five years, providing farmers with yet another tactic to manage herbicide resistance.

While waiting for the next innovation in weed management, farmers should continue practicing expert-recommended weed control strategies:

  • Use diversified herbicide modes of action
  • Apply herbicides at the full labeled rate
  • Use a zero-tolerance policy when scouting for weed escapes
  • Implement mechanical management, such as tillage, when necessary

For more information on weed management strategies you can be using now, visit http://www.iwilltakeaction.com/weeds/principles-of-resistance.

In the meantime, keep on top of herbicide chemistry and soybean trait approvals using the Take Action Seed Trait and Herbicide Approvals chart.

 

The Take Action program is not affiliated with any of these providers. The United Soybean Board and all Take Action partners neither recommend nor discourage the implementation of any advice contained herein and are not liable for the use or misuse of the information provided.