I apologize for bringing up seeded acres in Saskatchewan. But are herbicide resistant weeds in Saskatchewan relevant atleast? They have to be, otherwise there is no point in discussing these matters outside of Michigian, or wherever the article posted by Bagor was located, as it is local to them and not effecting the rest of the world. But that's wrong, herbicide resistance is everywhere.
In regards to RR weeds, it'd be more accurate to call them "group 9 resistant", and not "glyphosate resistant". Group 9 chemicals contain inhibitors of EPSP synthase, and these group 9 resistant weeds are no longer controlled by that mode of action. Glyphosate just so happens to be alone in this group 9, which is where the "glyphosate resistant" name comes from, but that is not to say that it always will be alone as chemical companies are developing new products in new groups every single year. And if/when they do develop another group 9 chemical containing EPSP synthase inhibitors, it will not kill the above mentioned weeds either.
I honestly just had a customer call me about an hour ago, and her concern directly relates to the discussions in this thread:
Customer: "I just sprayed Odyssey on my peas, and I don't think it's killing the kochia. Do I need to re-spray?"
Me: "Odyssey doesn't kill kochia anymore. It's a group 2 chemical, and 90% of the kochia in our fields have become resistant to group 2"
Customer: "Well my brother used Viper on his, and it doesn't seem to have killed it either"
Me: "And it won't, unfortunately. Viper is also a group 2. There is no way for us to kill kochia once peas or lentils are out of the ground because all of the chemicals we use on peas and lentils are group 2s. It has to be controlled pre-seed/pre-emergence"
Kochia in AB/MB/SK are no longer controlled by products like Express, Solo, Odyssey, Refine, Viper, Pursuit, Muster, Triton, etc, despite there never being a group 2 resistant GMO crop developed. All of these products I listed are group 2s, meaning they all contain ALS/AHAS inhibitors, which kochia has evolved to be resistant to due to repeated use of this specific mode of action against it.
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