FMC Corporation has submitted a regulatory dossier for rimisoxafen in Brazil, marking the second global regulatory filing for what the company describes as the industry’s first and only dual mode of action herbicide. The Brazilian submission follows FMC’s filing with the US Environmental Protection Agency in July 2026 and advances the company’s effort to bring new weed-management technologies to two of the world’s largest row-crop markets.
Brazil is a critical market for crop protection, with around 50 million hectares under soybeans and more than 20 million hectares under corn. Growers are increasingly confronting herbicide-resistant broadleaf weeds, adding pressure to existing weed-management programmes. Among the concerns is Amaranthus hybridus, which has developed resistance to glyphosate and acetolactate synthase (ALS) inhibitors. Amaranthus palmeri, meanwhile, is a regulated quarantine weed that poses a growing threat to crop productivity.
“Brazilian growers are facing complex weed resistance challenges that demand new and differentiated solutions,” said Leonardo Bastos, Vice President and Chief Marketing Officer at FMC. “Submitting rimisoxafen for regulatory review in Brazil is an important step forward, demonstrating our long-term commitment to this market and to the growers who depend on innovation to protect their crops and their livelihoods.”
Rimisoxafen has been classified by the Herbicide Resistance Action Committee (HRAC) under Groups 12 and 32. Its dual mode of action is intended to provide growers with another tool for diversifying weed-control programmes and supporting resistance-management strategies. According to FMC, extensive field testing has shown consistent activity against small-seeded broadleaf weeds, including populations resistant to other herbicides. The company has specifically reported activity against Amaranthus palmeri and Amaranthus hybridus.
The Brazilian filing also adds to FMC’s pipeline of novel herbicide active ingredients. Rimisoxafen is the third new herbicide active ingredient the company has advanced to regulatory submission in Brazil, following Isoflex active and Dodhylex active. FMC said the three submissions demonstrate the depth of its research and development pipeline and its focus on advancing next-generation crop protection technologies through regulatory review.
The company expects formulated-product submissions for rimisoxafen to follow as the Brazilian regulatory process progresses. The timing and outcome of the review remain subject to regulatory authorities. Importantly, rimisoxafen is not currently registered for sale or use in Brazil or any other country. FMC said no offer for sale, sale or use of the product is permitted before all required regulatory approvals are obtained.
The submission therefore represents a regulatory milestone rather than a commercial launch. For Brazilian growers dealing with increasingly complex resistance patterns, the significance of the technology will ultimately depend on regulatory approval, product formulation and its performance under local field conditions.
