Novel herbicidal active ingredient pyrasulfotole granted first regulatory approval

Bayer CropScience to launch new cereal herbicide Huskie® in the United States in 2008

Monheim.– Bayer CropScience has received the first regulatory approval for its new cereal herbicidal active ingredient pyrasulfotole from the Environmental Protection Agency (EPA) in the United States. The company is now preparing to launch the innovative product under the brand name Huskie® in the United States, one of the biggest cereal markets in the world. This means that Huskie® will be available in good time for the spring season 2008. Further registrations are expected in Canada and Australia later in the course of 2007.

“The approval of pyrasulfotole in the United States and the successful launch of our new corn product tembotrione in Europe at the start of this year are enabling us to strengthen our portfolio of innovative herbicides. Our aim is to further expand our leading position in the area of new herbicidal active ingredients”, Dr. Rüdiger Scheitza, member of the board of management of Bayer CropScience and Head of Portfolio Management, explained. “Our portfolio of new herbicidal active ingredients launched since 2000 has already generated over EUR 250 million in sales in the first six months of 2007 - an increase of 15% over the previous year”, Scheitza added.

Including pyrasulfotole and tembotrione, the current launch program started in 2000 comprises 26 active ingredients to be launched by 2011 which cover all the indications and have a combined peak sales potential of approximately EUR 2 billion.

Pyrasulfotole: One innovative mode of action – triple effect

Pyrasulfotole brings a new mode of action to the cereal herbicide market segment. It is the first HPPD (4-hydroxyphenylpyruvate dioxygenase) inhibitor for cereals in North America. Pyrasulfotole offers the farmer excellent performance against a broad spectrum of broad-leaved weeds. Huskie® can be used as part of an effective resistance management program to control sulfonylurea-resistant weeds. The new product will also help the farmer to optimize cereal production.

The new mode of action developed by Bayer CropScience works by interrupting three crucial processes during the growth stage of weeds. Firstly, pyrasulfotole blocks the plant’s ability to generate an adequate supply of energy by photosynthesis. Secondly, it restricts the weed’s ability to produce vitamin E, which protects biological membranes against oxidative stresses and the photosynthetic apparatus against photoinactivation. As a result, so-called free radicals destroy the weed from the inside. Furthermore, pyrasulfotole prevents carotenoid production, i.e. the weed loses the shield that protects chlorophyll molecules from UV rays and excess light. As there is nothing to stop sunlight from penetrating deep into the leaves, the chlorophyll is destroyed: the weed dies.