Glyphosate resistance confirmed

The first case of a glyphosate-resistant weed in Canada has now been confirmed. University of Guelph researchers working in conjunction with Monsanto Canada have confirmed glyphosate resistance in a population of giant ragweed in Ontario. The finding is the result of research that began in late 2008 when a resistant population was first suspected. Not only do the plants survive increased rates of glyphosate, but they also have the ability to pass the trait along to the next generation. At this point, the resistance has only been confirmed from a single field site. Other giant ragweed populations in southwestern Ontario are also being tested. Monsanto says there are a total of 17 weed species in countries around the world with confirmed resistance to glyphosate. Ten of those species are in the United States. While this is the first case in Canada, it won’t likely be the last. Other types of herbicide resistance are already firmly entrenched. A total of 30 species of weeds in Canada have developed resistance to some type of herbicide. Guarding against resistance and learning to cope with resistance will be important aspects of farm management in the years ahead. I’m Kevin Hursh.