The NFU is taking steps to avoid resistance developing to glyphosate, following the chemical’s reauthorisation by the European Union last November.
Globally, over 30 weed species are believed to have developed resistance to the active ingredient of Monsanto’s widely used Roundup weed killer, although no resistant species have yet been identified in the UK.
Last autumn the NFU held a resistance management workshop, bringing together farmers, sprayer operators, researchers, academics, manufacturers, agronomists and others to try to understand why and where resistance to the chemical had developed in Europe.
Following the European Commission vote, AHDB, the Agricultural Industries Confederation, the NFU and the Weed Resistance Action Group (WRAG) have worked alongside the likes of Monsanto and Syngenta to review guidance and update resources.
The union is now calling on these stakeholders to collaborate and share knowledge to prevent, or at least delay, resistance developing in the UK.
Enhanced stewardship guidelines have been produced and can be found on the AHDB website.
The NFU warned that high-risk practices are often used, which could encourage UK weeds to develop resistance to glyphosate. In response, guidelines were produced by WRAG in 2015 to help agronomists and growers maintain the active ingredient’s efficacy in the UK.
The guidelines included four key messages, supported by more detailed evidence and guidance:
1) Avoid repeat applications to surviving plants.
2) Apply the right dose rate, at the right timing, in the right conditions. Reduced application rates increase the risk of reduced efficacy.
3) Use non-chemical options such as cultivation where practical, and use other herbicides in sequence.
4) Remove surviving weeds and report potential resistance issues to your advisor and/or the product manufacturer.