W Australian farmers urged to act on glyphosate resistance
Farmers in the Australian state of Western Australia have been urged to adopt additional measures to stem the spread of glyphosate herbicide resistance in ryegrass (Lolium rigidum). A recent survey showed that about 60% of samples in one area contained plants resistant to the herbicide, while earlier surveys had shown resistance levels of 40%, according to the state Department of Primary Industries. It is encouraging farmers to restrict the movement of ryegrass seeds between fields by strict measures to control plants that survive glyphosate treatments. Growers should use a "double knock" treatment with bipyridyl herbicides, rotate herbicides, bury seed by cultivation or use other seed reduction treatments, the Department points out. Meanwhile, glyphosate resistance in a red brome (Bromus rubens) population has been confirmed in Western Australia. It is the first such case in the world, the Department notes.