Researchers in Argentina have confirmed the first instance of Amaranthus hybridus resistance to the herbicide sulfentrazone, highlighting a growing challenge for agricultural systems in the country.
In Argentina, the issue of weed resistance to herbicides is becoming a significant concern for agricultural production systems. A team of researchers from the Faculty of Agricultural Sciences at the National University of Rosario and the IICAR-CONICET has documented the first instance in Argentina of the weed species Amaranthus hybridus exhibiting resistance to the herbicide sulfentrazone. This herbicide is a commonly used pre-emergence treatment for controlling weeds in crops such as soybeans and sunflowers.
Amaranthus hybridus has a noted history of resistance worldwide, with a total of 38 confirmed populations resistant to five different groups of herbicides, including glyphosate and ALS inhibitors. In Argentina specifically, previous records indicated only one case of resistance to post-emergence fomesafen in 2022, while no instances of resistance to sulfentrazone had been documented previously, aside from regional reports. This new finding underscores the expanding scope of herbicide resistance among weeds in the agricultural landscape.
The implications of this discovery are significant for farmers and agricultural stakeholders in Argentina. The confirmation of resistance to sulfentrazone could require adjustments in weed management strategies and highlight the need for integrated approaches to weed control. As herbicide resistance dynamics continue to evolve, ongoing research and monitoring will be crucial to mitigate its impact on crop production and ensure sustainable agricultural practices moving forward.
