The Fungicide Resistance Action Group (FRAG-UK)

The Fungicide Resistance Action Group (FRAG) produces guidance on pesticide resistance issues. Hosted by AHDB, this information can be used to help protect crops and the long-term efficacy of fungicides.

The AHDB-supported Resistance Action Groups (RAGs) are informal, UK-based groups consisting of experts from the Crop Protection Association (CPA) member companies, other representatives from the agrochemical industry, a range of independent organisations, including public-sector research institutes, and the Chemicals Regulation Directorate (CRD).

About the Fungicide Resistance Action Group (FRAG)

Insecticide Resistance Action Group (IRAG)

Weed Resistance Action Group (WRAG)

FRAG guidance

Fungicide resistance management (general 2024)

Fungicide resistance management (cereals 2024)

Fungicide resistance management (oilseed rape 2024)

Fungicide resistance management (potato late blight 2024)

Fungicide resistance management (soft fruit 2022)

Fungicide resistance management (apple and pear pathogens 2015)

General resistance management guidelines

Good resistance management is based on limiting the level of exposure of the target pathogen to the fungicide.

  • Fungicide input is only one aspect of crop management and other integrated control measures should always be used, such as disease-free seed lots, good hygiene through disposal of crop debris and control of volunteers which may harbour disease
  • Always aim to select varieties exhibiting a high degree of resistance to diseases known to be prevalent in your area, in addition to the main agronomic factors you desire
  • Avoid growing large areas of any one variety, particularly in areas of high disease risk where the variety is known to be susceptible
  • Only use fungicides in situations where the risk or presence of disease warrants treatment
  • Use a dose that will give effective disease control and which is appropriate for the variety and disease pressure
  • Make full use of effective fungicides with different modes of action in mixtures or as alternate sprays
  • Ensure that mixing partners are used at doses that give similar efficacy and persistence
  • Monitor crops regularly for disease and treat before the infection becomes well established
  • Avoid repeated applications of the same product or mode of action and never exceed the maximum recommended dose or number of applications

How fungicide resistance happens

Usually, fungicides control susceptible fungal strains effectively. However, any resistant strains present – through mutation or natural variation – are more likely to survive and reproduce. This process of ‘selection’ makes each subsequent generation more difficult to control. In the absence of any fitness costs, resistant strains may come to dominate the population, causing disease control to fail. This video by the Fungicide Resistance Action Committee (FRAC) explains why fungicide resistance happens and how to manage it.

Visit the Fungicide Resistance Action Committee (FRAC) website

Mode of action labelling for UK plant protection products

From 2023, all UK plant protection products will include mode of action (MoA) information on their labels.

The decision – by the Health and Safety Executive (HSE) – follows a joint statement issued by the UK Resistance Action Groups (UK-RAGs) in December 2017. This said that greater prominence of MoA information would help farmers and agronomists make informed resistance management decisions.

Since then, members of the industry body ‘CropLife International’ have made a voluntarily commitment to include MoA icons and groups on all product labels by 2023. Following consultation with the Crop Protection Association (CPA), the HSE announced that it will become a legal requirement to include MoA information on all UK product labels from January 2023.