Digging into Research
Glyphosate resistance was detected in 87% of kochia samples, while 45% were dicamba-resistant Kochia resistant to multiple modes of action is a significant problem across the Canadian Prairies. Herbicide resistance to Group 2 ALS inhibitors was first identified on the Prairies in 1988, and a 2007...
Overwintering kochia plants, 7 to 8 months after plant senescence the previous fall, retained an estimated 2091 ± 297 seeds per plant in May. This represented an average estimated at 18.5 ± 1.9% of total seed production. Research has shown that kochia has a relatively short...
Kochia with resistance to glyphosate was found at 78% of sites sampled, with 44% of sites exhibiting fluroxypyr resistance, and 28% with dicamba resistance. Triple resistance to Group 2 ALS inhibitors, Group 9 glyphosate, and one of the Group 4 synthetic auxins was found at...
For livestock producers, kochia is relatively high in crude protein and can be used as an alternative forage for alfalfa, or ensiled and used as an alfalfa silage replacement. Integrated crop-livestock systems may offer alternative weed control methods that are effective for managing herbicide-resistant kochia...
Yield losses caused by kochia competition are high, with mean losses reported to be 68% in grain corn, 62% in sorghum, 52% in soybean, 46% in sugar beet, 40% in silage corn, 23% in sunflower, 20% in spring wheat, 13% in canola and field pea,...
Layering Group 14 herbicides saflufenacil or carfentrazone + sulfentrazone pre-plant with a Group 2/6 imazamox/bentazon post-emergent treatment can effectively control glyphosate- and ALS inhibitor-resistant (Group 9 + 2) kochia in field pea. Layering will also help to reduce herbicide selection pressure through the use of...
Weed control has typically focussed on preventing yield loss with the side benefit of controlling weed seed return to the seedbank. This research proposes to turn that approach on its head by developing an understanding of when weed control is critical to prevent the return...
A randomized-stratified survey of 315 sites in Manitoba found that, overall, 58% of the kochia populations tested were glyphosate-resistant, while 1% were dicamba-resistant. There was a rapid increase in glyphosate-resistant kochia over a five-year time frame, and the survey also confirms the first cases of...
In a 2017 Alberta survey, 13% of the kochia populations sampled were fluroxypyr-resistant. Only 4% of the populations were both fluroxypyr- and dicamba-resistant, indicating that different mechanisms may confer resistance to these herbicides. When combined with estimates of dicamba resistance, about 28% of kochia populations...
Control of glyphosate-resistant kochia was achieved with the use of effective tank-mixtures utilizing Group 4, 14 or 4+19 herbicide groups. But the confirmation of Group 4 resistance in kochia highlights the need for careful herbicide stewardship to prevent further selection of multiple herbicide-resistant kochia. In 2011,...