Glyphosate- and acetolactate synthase inhibitor-resistant kochia (<i>Bassia scoparia</i>) control in field pea

Kochia [Bassia scoparia (L.) A.J. Scott] is an invasive C 4 tumbleweed in the Great Plains of North America, where it impedes crop harvest and causes significant yield losses. Rapid evolution spread glyphosate- acetolactate synthase (ALS) inhibitor-resistant kochia western Canada limit herbicide options available for control these biotypes field pea (Pisum sativum L.); one predominant pulse crops grown this region. Field experiments were conducted near Lethbridge, Alberta, 2013–2015 Coalhurst, 2013–2014 to determine which effectively ALS pea. Visible injury was minor (0%–4%) all environments except Lethbridge 2013, pre-plant (PP) flumioxazin treatments containing post-emergence (POST) imazamox/bentazon resulted unacceptable (14%–23%) visible Herbicide impacts on overall. Carfentrazone + sulfentrazone PP saflufenacil followed by POST ?80% environments, while alone reduction biomass compared with untreated (albeit, absent statistical difference Coalhurst 2014). These results suggest that layering protoporhyrinogen oxidase-inhibiting herbicides or carfentrazone ALS- photosystem II-inhibiting combination can also mitigating further selection resistance through use multiple effective modes-of-action.