Bayer CropScience has a new postemergence corn herbicide in the works that's slated to be marketed later this decade. At this point, the herbicide doesn't even have a name, nor is it approved by or registered with the Environmental Protection Agency.

However, officials with the company anticipate a full commercial launch in 2009.

They gave some background on the product at December's North Central Weed Science Society annual meeting in Kansas City, Missouri.

Excellent broadleaf control

The herbicide is currently a numbered compound called AE 0172747. Bayer CropScience officials have proposed the common name of tembotrione for the herbicide. (At this point, the tembotrione name has not been confirmed.) Bayer CropScience officials say the product has excellent crop safety.

Company officials say the compound will be the next level in weed control in corn when compared with Callisto, another postemergence corn herbicide. Callisto contains the active ingredient mesotrione. Mesotrione and AE 0172747 share the same mode of action of being an HPPD inhibitor. Like mesotrione, AE 0172747 gives excellent control of broadleaves.

For example, company tests show control in the low 90% range for waterhemp and redroot pigweed by both compounds. Broadleaves AE 0172747 controls include:

Amaranthus species

Carpetweed

Common cocklebur

Kochia

Ladysthumb

Common lambsquarters

Mallow

Morninglory species

Mustards

Nightshade

Giant and common ragweed

Pennsylvania smartweed

Common sunflower

Russian thistle

Velvetleaf

Where AE 0172747 differentiates itself from mesotrione is grass control. Bayer CropScience tests show AE 0172747 boosted control of barnyardgrass to 99%, above mesotrione’s 87% control. Meanwhile, AE 0172747 had 96% control on shattercane, compared to mesotrione’s 38% control.

Large and smooth crabgrass

Woolly cupgrass

Giant, green, and yellow foxtail

Goosegrass

Seedling Johnsongrass

Junglerice

Wild proso millet

Texas panicum

Bayer CropScience officials recommend a tank mix for additional grass control. AE 0172747 is stronger than mesotrione on yellow foxtail, giving 81% control in Bayer CropScience trials compared to 20% control for mesotrione. However, company officials point out tank mixing AE 0172747 with atrazine can boost yellow foxtail control.

Bayer CropScience has a new postemergence corn herbicide in the works that's slated to be marketed later this decade. At this point, the herbicide doesn't even have a name, nor is it approved by or registered with the Environmental Protection Agency.