The Resistance Roadshow (winter 2025/26)

Industry experts translated complex science into clear, practical ways to tackle pest, weed and disease resistance in arable crops, as part of our Resistance Roadshow in 2026. Learn about the initiative and access post-event resources.

These in-person events brought together:

• Regional farmers
• Advisors
• Defra
• AHDB
• NIAB
• ADAS
• The Voluntary Initiative
• Rothamsted Research
• Harper Adams University

These events covered:

• Resistance management of pests, weeds and diseases of arable crops
• The impact of resistance on profit and production
• Current resistance risks and trends
• How to identify resistance, interpret data and apply the findings
• Practical, on-farm solutions to prevent and manage resistance
• Regional case studies and interactive workshops
• Q&A sessions with leading experts

*Video starts with an overview of pesticide resistance.

We developed a workbook to support the Resistance Roadshow events that provides practical tips on insect pest, weed and disease resistance management. 

The workbook:

• Explains the key resistance management terms and principles
• Describes the causes of resistance
• Features tips on how to identify resistance
• Provides examples of how to use integrated pest management (IPM) to address the main pest, weed and disease threats on your farm
• Highlights more resources and guidance

If you would like a digital version of the workbook, please contact laura.james@ahdb.org.uk

We have selected some top picks on resistance management from the AHDB Knowledge Library, below.

In the 1970s, systemic fungicides with specific modes of action were introduced. Ever since, the number of fungicide resistance cases has gradually increased. However, most fungicides are still very effective against the target organisms for which they were developed. Resistance risks depend on the pathogen species and mode of action group. For example, when fungicides affect many physiological processes within the target pathogen (multi-site products), they are much less prone to resistance.

AHDB guidance

Following the introduction of synthetic organic insecticides in the 1940s, it did not take long for insecticide resistance to be recorded. By 1947, resistance to DDT was confirmed in houseflies. With every insecticide introduction, cases of resistance developed in key pest species two to 20 years later. Resistance increases fastest in situations where insects reproduce quickly, there is little or no immigration of susceptible individuals and pests are subjected to frequent sprays with the same insecticide. Additionally, some pests (e.g. aphids in protected crops) may originate from genetically diverse, sexually reproducing, populations on imported plant material. Resistance is present in numerous crop pests, including key cereal aphids and cabbage stem flea beetles, with insecticide options often extremely limited.

AHDB guidance

Herbicide resistance was first identified in black-grass in 1982. There are now many examples of herbicide resistance in grass weeds. This now even includes glyphosate resistance in some Italian rye-grass populations – the first UK weed to develop resistance to this commercially important mode of action (announced in 2025). For broad-leaved weed (BLW) resistance, most cases are associated with the ALS-inhibitor group of herbicides (first identified in the UK at the turn of the millennium). For weeds, it is particularly important to account for the resistance profiles in fields (in addition to all resistance risks) when developing herbicide programmes.

AHDB guidance

Access key AHDB resources via our integrated pest management (IPM) hub, including resources from the Recommended Lists for cereals and oilseeds (RL).

Variety choice forms the foundation of IPM.

• 21 January 2026: West
• 22 January 2026: East Midlands
• 27 January 2026: Scotland
• 10 February 2026: North East (Morpeth)
• 11 February 2026: North East (Driffield)
• 19 February 2026: Northern Ireland
• 25 February 2026: South East

Funded by Defra.