Herbicide resistant weeds are not a novelty anymore, they are the norm. New cases of confirmed and suspected weed resistance to herbicides are steadily reported in all crops and cases of multiple resistances (weed biotypes resistant to more than one group of herbicides) are becoming more common.
We hear about glyphosate resistant weeds in field crops regularly. Fruit and vegetable crops are not spared from this epidemic. From my perspective, resistant weeds are an even more pressing issue in fruit and vegetable crops because there are far fewer herbicides available and resistance management can very quickly translate into costly hand weeding.
In 2017, a limited survey was conducted in vegetable crops to aid in the development of quick tests to confirm suspected cases of herbicide resistant weeds. To detect resistance as quickly as possible genetic tests are ideal. These quick tests will provide producers with results in 2 weeks. This will allow for in season management and prevent the resistant weeds from spreading. In comparison, conventional tests can take up to one year to complete.
A total of 10 quick tests have been developed. These include:
- Group 2 (e.g. Pursuit, Prism, etc.) resistant giant foxtail (Setaria faberii)
- Group 2 (e.g. Pursuit, Prism, etc.) resistant redroot pigweed (Amaranthus retroflexus)
- Group 2 (e.g. Pursuit, Prism, etc.) resistant common ragweed (Ambrosia artemisiifolia)
- Group 2 (e.g. Pursuit, Prism, etc.) resistant waterhemp (Amaranhus rudis)
- Group 2 (e.g. Pursuit, Prism, etc.) resistant common chickweed
- Group 2 (e.g. Pursuit, Prism, etc.) resistant Eastern black nightshade (Solanum ptychanthum)
- Group 5 (e.g. Sencor, Sinbar, Princep, Gesagard, etc.) resistant lamb’s-quarters (Chenopodium album)
- Group 7 (e.g. Lorox) resistant common ragweed (Ambrosia artemisiifolia)
- Group 9 (e.g. glyphosate) resistant waterhemp (Amaranhus rudis)
Source : ONfruit