Article

by Carey Gillam

CHICAGO (Reuters) - In a nod to concerns about overuse of its popular Roundup herbicide, Monsanto Co (MON.N) said it would try to layer its popular "Roundup Ready" cropping system with a similar system based on a rival herbicide.

"We've relied on it too long by itself," Monsanto executive vice president of sustainability Jerry Steiner said of the company's Roundup herbicide, in an interview on Monday at the Reuters Food & Agriculture Summit.

For decades Roundup has been a top selling herbicide for farm fields around the world as well as for recreational and residential users. Monsanto, the world's largest seed company, has genetically modified corn, soybeans and other crops to tolerate treatments of Roundup, making killing weeds easier for farmers. And Roundup Ready soybeans, corn and cotton have driven rapid revenue growth for Monsanto over the last decade.

But as usage has grown, complaints have also mounted. Critics say heavy use of glyphosate-based Roundup have created multiple strains of herbicide resistant weeds. These so-called 'super weeds' in some areas are choking out crops.

Monsanto said Monday that it was collaborating with rival BASF (BASFn.DE) to develop dicamba-tolerant cropping systems. The companies have granted each other reciprocal licenses, with BASF agreeing to supply formulated dicamba herbicide products to Monsanto.

Monsanto said it would aim to commercialize dicamba-tolerant crops system, including innovative dicamba formulations proprietary to BASF, and the dicamba tolerant trait for soybeans, which is proprietary to Monsanto.

The system is expected to be introduced in the United States and Canada in the middle of this decade, pending regulatory approvals.

"What we want to see happen for weed control is to get two modes of action on every acre," said Steiner. "The dicamba will provide another great opportunity for a second mode of action that will pick up on broadleaves. It is a very effective herbicide. This partnership will bring really good farmer-friendly formulations to the marketplace."

Both Monsanto and BASF will have the right to commercialize new dicamba herbicide formulations for use with dicamba tolerant crops and the right to develop their own mixtures with certain herbicides.

Monsanto first plans to introduce the dicamba tolerance trait stacked with its new Genuity Roundup Ready 2 Yield soybean trait. Monsanto also has corn, cotton and canola dicamba tolerant crops in its research and development pipeline.

Experts estimate glyphosate-resistant weeds have infested close to 11 million acres so far. More than 130 types of weeds have developed levels of herbicide resistance in more than 40 U.S. states, more resistant weeds than found in any other country, according to weed scientists.

(Reporting by Carey Gillam; Editing by Tim Dobbyn)