Verdesian Life Sciences announces a new product that will soon give growers of cereal crops, grass seed, alfalfa and managers of rangeland and non-cropland areas access to a new biological herbicide for suppression of downy brome.

Discovered by scientist Ann Kennedy with the USDA-Agricultural Research Service, the bacterium Pseudomonas fluorescens, strain D7, offers significant activity to combat downy brome, commonly known as cheatgrass. D7 has been further developed for the commercial market by Verdesian Life Sciences. 

An invasive species, downy brome infests millions of acres of cropland, rangeland and non-crop areas across the U.S. The weed, which outcompetes native grasses, is especially troublesome for winter wheat growers as its development cycle parallels that of winter wheat. In rangeland and non-crop areas, the unwanted plant has virtually eliminated native grass species and the highly flammable weed blankets the ground to provide fertile fuel for brush fires. In addition, the seeds produced by this invasive weed are very irritating to grazing animals and can induce significant stress in livestock.

The plant’s extensive root system is a key to downy brome’s proliferation. D7 suppresses the weed’s development and growth. For wheat growers who currently control the weed with herbicides that inhibit acetolactate synthase (ALS), D7 will offer a second mode of action to improve activity and help protect against resistance development. 

Uniquely, D7 does not control weeds through pathogenic interactions but rather through the secretion of chemicals selectively suppressive to cheatgrass.

“Most herbicides for control of cheatgrass are ALS-inhibiting,” says Ryan Bond, Verdesian’s vice president of marketing. “We’ve seen some resistance development in the last few years, and D7 will give growers a tool to help mitigate that risk by offering a novel mode of action.”

D7 will be used at low use rates of 2 grams per acre and it can be applied in-furrow, via aerial application or as a seed treatment. D7 will be commercially available in 2015.