Mesosulfuron

Trade name(s) Osprey

Manufacturer(s) Bayer CropScience

Formulation(s) 4.5% water-dispersible granule

Remarks Postemergence herbicide used primarily to control annual grasses and some broadleaf weeds in winter wheat.

Water solubility 7 ppm at pH 5; 48 at pH 7

Storage conditions Protect from extreme heat and cold

Acute toxicity LD50 - greater than 5,000 mg/kg

Action in plant Inhibits the acetolactate synthase (ALS) enzyme, resulting in rapid cessation of cell division and plant growth in both roots and shoots.

Site of action Group 2: acetolactate synthase (ALS) inhibitor

Chemical family Sulfonylurea