Agricultural Uses
At a rate of 2.5–10 g a.i. ha−1, iodosulfuron‐methyl‐sodium (AE F115008) controls more than 50 different broadleaf weed species, including some very competitive weeds that cause a substantial reduction of cereal productivity, for example, G. aparine, M. chamomilla, S. media, Raphanus ssp., Cirsium arvense, and Lamium ssp. While the application of iodosulfuronmethyl‐ sodium at the lower end of the suggested use rate is usually sufficient for control of broadleaf weeds, a higher rate is needed for consistent grass weed control. Major grass weeds controlled with a 7.5–10 g a.i. ha−1 dose rate applied at the three‐leaf stage up to the end of tillering are Agrostis gigantea, A. spica‐venti, Lolium multiflorum, L. perenne, L. persicum, L. rigidum, Phalaris brachystachys, P. canariensis, P. paradoxa, P. annua, and P. trivialis.
When introduced in 1999, iodosulfuron‐methyl‐sodium was the first “safened” sulfonylurea herbicide available commercially and has been marketed by Bayer CropScience for use both in cereals and maize. A “safener,” such as mefenpyr‐ diethyl, is a chemical that, when applied to crop plants, reduces the injury caused by herbicides to an acceptable level. Ideally, a safener does not reduce activity against the target weeds. When a series of experiments was conducted to compare the behavior of iodosulfuron‐methyl‐sodium with and without mefenpyr‐diethyl as safener, the results suggested that the safener acted via a specific catalytic enhancement of herbicide degradation in cereals, but not in target weeds such as wild oat.
In cereals, iodosulfuron‐methyl‐sodium is available commercially under the trade name “Hussar” as a straight product in a 1 : 3 ratio with mefenpyr‐diethyl as safener. The compound is also sold in various combinations with other mixing partners, such as “Hussar® OF” (+ fenoxaprop‐p‐ethyl + mefenpyr‐diethyl), “Sekator®/Chekker®” (+ amidosulfuron + mefenpyr‐diethyl), “Cossack®” (+ mesosulfuron + mefenpyrdiethyl), and “Atlantis®” (+ mesosulfuron + mefenpyr‐diethyl).
