The planting of round up resistant sugar beets and canola ( as well as cotton, corn, and soybean) is causing the spreading of the resistance to weeds like Kochia, a seven foot tall weed that handles drought conditions very well. This is forcing Monsanto and it’s rivals to modify their seeds even more with other genes to resist other weedkillers since Monsanto’s proprietary Round Up isn’t working on these plants.
To read more, see the story on Bloomberg – http://www.bloomberg.com/news/2012-01-12/monsanto-says-glyphosate-resistant-kochia-in-western-canada.html
