Foliar fungicide activity and seed treatment options for barley

These tables indicate how key active ingredients may perform against various barley pathogens. Use this information, alongside our fungicide performance results and resistance management guidance, to select fungicides that match the primary disease risk(s) in barley.

• Table 1 indicates potential control levels for key active ingredients against several diseases, as tested by AHDB in fungicide performance trials and other research projects
• It also includes label claims of activity for active ingredients not tested by AHDB
• Actual control will depend on dose and timing, as well as the primary disease risk (which is mainly influenced by the variety, sowing date, location and weather)
• Table 2 shows label recommendations for seed treatments

Any control level indicated on Table 1 does not guarantee label approval. Additionally, other active ingredients may be registered for the control of these diseases. Always check plant protection product labels before use.

Product labels provide information on efficacy claims, which may include graduated control levels based on disease observations in trials. Further information is available in the HSE efficacy guidelines: 405 and 407, which cover data requirements for brassicas (including oilseed rape) and cereals (and maize), respectively.

Products in mixtures may contain different loadings and formulations, which may impact control.

5 = Highest control level

1 = Lowest control level

- = Insufficient data

[] based on limited or old data

L = Label claim of activity for products not tested by AHDB

X = Seed treatment label recommendation (check product label for information on whether control is full or partial)

Reviewed: April 2026.

Table 1a. SDHI and SDHI mixtures (SDHIs shown first)

*Significant resistance risk. Always use SDHI fungicides in mixture with at least one fungicide from an alternative mode of action group that has efficacy against the target pathogen(s). SDHI Mixtures with different active ingredient loadings are available, which may have different efficacy to those tested.

Note: Isopyrazam withdrawal: Grace-period information

The GB approval of the pesticide active substance isopyrazam expired on 31 March 2026 (it is not approved for use in Northern Ireland).

This impacts all GB plant protection products that contain isopyrazam, with the following grace periods set:

• Six months for sale and distribution (until 30 September 2026)
• A further 12 months for storage, disposal and use of existing stocks (until 30 September 2027)

Table 1b. DMI/azoles**

**Prochloraz (poraz) is from the imidazole chemical group, all other DMIs cited are from the triazole chemical group (both chemical groups are from FRAC Group code 3).

Table 1c. QoI (strobilurin) and Qol mixtures (Qol shown first)

Table 1d. Others

Table 1e. Mildewicides only

Reviewed: March 2024.

*Seedborne disease.
**Barley seed treated with Vibrance Duo must not be used for seed multiplication (certified seed).
No label recommendations for the control of yellow rust, aphids/BYDV or slugs.

Treated-seed spills are most often associated with filling, (poor) calibration and moving the seed drill. To minimise the risk to wildlife and the environment, always:

• Minimise spill risks
• Apply via qualified operators
• Use calibrated equipment
• Follow product labels
• Fill drills from as low a height as possible
• Deal with spills immediately (ideally, use a spill kit)
• Ensure undrilled seed is disposed of properly
• Avoid retaining treated seed after drilling
• If required, store it in dry conditions away from temperature extremes (if this is done, the germination should be sufficient for the following year)

Note: Unrequired treated seed can be sown to a ‘sacrificial’ area and subsequently removed by cultivation or spraying. If this is not appropriate, dispose of treated seed via a licenced waste contractor.

When planning fungicide programmes, it is essential to account for resistance management. Mixtures and alternations of fungicides, with different modes of action, are often most effective and reduce resistance risks.