AP Fungicides

Introduction and General Information

Go directly to FRAC-Recommendations for Resistance Management for AP Fungicides.

AnilinoPyrimidines (AP) are highly active fungicides against a broad range of fungi. The FRAC AP Working Group discusses the sensitivity situation and use guidelines for control of Botrytis and Venturia for the commercialized AP fungicides cyprodinil, pyrimethanil and mepanipyrim.

The use of APs for control of Black Sigatoka is included in the FRAC Banana Working Group.

All of the above-mentioned fungicides exhibit cross-resistance and are grouped under the FRAC Group 9 in the FRAC Code List.

Code Target site of action Group name Chemical group Common name Comments
9 methionine biosynthesis (cgs gene, proposed) AP - fungicides (Anilino- Pyrimidines) anilino- pyrimidines  cyprodinil            mepanipyrim               pyrimethanil Resistance known in Botrytis and Venturia, sporadically in Oculimacula.

Medium risk

See FRAC Anilinopyrimidine guidelines for resistance management

The mode of action includes inhibition of methionine biosynthesis and secretion of hydrolytic enzymes. APs are cross-resistant, but show no cross-resistance with other fungicide groups.

Sensitivity monitoring studies over several years have shown that there is a medium resistance risk of Botrytis and Venturia to APs.

FRAC Recommendations for AP fungicides

General Use Recommendations (all crops)

(Reviewed in 2022, no changes compared to 2021)

The purpose of the use guidelines for AP containing products is to maintain the sensitivity in the target pathogens and to prevent crop losses due to resistant pathogen populations.

  • For grey mold and apple scab control, specific guidelines have been developed. In general, where different AP-containing products are used in one season, the cumulative number of applications with cyprodinil-, pyrimethanil- or mepanipyrim-containing products must not exceed the maxima as mentioned below.
  • For sound resistance management, good agricultural practices, including phytosanitary measures and crop protection, should be followed not only in commercial practice, but also in nurseries.
  • The use recommendations were reviewed during the meeting on January 17th, 2022. The Botrytis and Venturia guidelines have not been changed.
  • For all other pathogens and crops, specific guidelines are not yet regarded to be needed. However, the maximum number of applications should be limited and should not exceed more than 50% of all treatments.

Specific Recommendations by Pathogens

  • Where up to three treatments are made per season, the number of applications of AP-containing products is limited to one.
  • In situations where four to six Botrytis treatments are made per crop and season, a maximum of two applications with AP-containing products are recommended.
  • In specific situations where seven or more Botrytis treatments are required per crop and season, a maximum of three applications with AP-containing products is recommended and not more than two consecutive applications.
  • For specific crops and products, follow use recommendations of individual companies.

  • Apply a maximum of four AP-containing products per season.
  • In locations where resistance has been reported, use APs only in a mixture with an effective non-cross-resistant scab fungicide.
  • Individual products should always be used at recommended dose rates and during the period when they are most effective.
  • Curative use only in conjunction with reliable scab warning systems.

For a printer friendly version of these use recommendations, please refer to the most recent Minutes in the table below (PDF-document, last pages).

Monitoring Results and Recommendations

At the annual meeting, the working group reviews the current year's monitoring results and decides whether they require changes be made to the next year's use recommendations.  The minutes of those meetings are below.