Research and development of a novel rice herbicide, pyrimisulfan#

Pyrimisulfan is a novel paddy herbicide that was discovered and developed by Kumiai Chemical Industry Co., Ltd.; Ihara Chemical Industry Co., Ltd.; and K-I Chemical Research Institute Co., Ltd. It was registered in Japan in 2010 and launched the first one-shot herbicide containing only one active ingredient (a.i.) developed with our original formulation technology. The compound is sulfonanilide, having a pyrimidinyl-containing group at the 2′-position and an acetolactate synthase (ALS) inhibitor. Pyrimisulfan shows broad-spectrum weed control against annual grass, sedge, broadleaf, and sulfonylurea-resistant weeds without causing phytotoxic injury to rice. At doses of 50–75 g a.i./ha, pyrimisulfan has a wide application window and exhibits long residual activity against these weeds. Pyrimisulfan has favorable toxicological, ecotoxicological, and environmental profiles.