Zonal Efficacy Assessments



In the framework of the EU regulations, mutual recognition and zonal authorizations are core principles when submitting dossiers for the registration of plant protection products. As many of the technical details for conducting zonal authorizations needed to be harmonized among countries, EPPO has developped Standards on this issue. In addition to these recommendations, EPPO is also providing examples of zonal efficacy evaluations for specific cases. 


Although the outcomes of this work are directly relevant to EU Member States, it is acknowledged that the principles defined for zonal evaluation may be used by other EPPO member countries wishing to adopt the zonal concept for the authorization of plant protection products.



EPPO Standards related to zonal efficacy assessments

In establishing a zonal dossier, not only should trials be conducted according to harmonized procedures, but the applicant and the registration authority should be able to establish the relevance of the data in relation to climate. To this effect, the EPPO Standard PP 1/278 describes the principles to be considered when designing a trials series for the generation of efficacy data to support an authorization of a plant protection product across a substantive area or region, such as across one or more distinct geographic areas or countries. The other two EPPO Standards aim to assist both regulatory authorities and applicants in determining the comparability of conditions between given areas within the EPPO region (PP 1/241) and also extends the climatic comparisons globally (PP 1/269).


  • PP 1/241 – Guidance on comparable climates 
  • PP 1/269 – Comparable climates on global level 
  • PP 1/278 – Principles of zonal data production and evaluation


The lastest versions of the above standards can be accessed from the EPPO database on PP1 Standards 




Examples of zonal efficacy evaluations

Important note: These documents are intended to assist applicants and evaluators to interpret EPPO Standard PP1/278 Principles of zonal data production and evaluation. They provide specific examples of the data required to support intended uses. It should be noted that the number and distribution of trials will vary depending on the zone and the intended use. Expert judgement should be applied in all cases. These examples are ‘working documents’ meaning that they may be modified over time, and that further examples will be added when they are completed. The approval body for these documents is the EPPO Working Party on Plant Protection Products.


Product Pest Crop Zone
Herbicide Apera spica-venti - Loose silky bent (APESV) Winter wheat European Central Zone
Herbicide Weeds Maize European Central Zone
Herbicide Weeds Succeeding crops European Union
Fungicide Mycosphaerella graminicola - Septoria leaf blotch (SEPTTR) Winter wheat European Central Zone
Fungicide Puccinia striiformis f. sp. tritici - Yellow rust (PUCCST) Wheat European Central Zone
Fungicide Venturia inaequalis - Apple scab (VENTIN) Apple European Central Zone
Insecticide Aphids, thrips and whiteflies
Ornamental plants in greenhouses
European Union
Insecticide Wireworms Various crops such as maize, sunflower, millet and sugar beet European Union
Plant Growth Regulator Clarification of efficacy data requirements for the authorization of a plant growth regulator in winter oilseed rape in the European Central authorization zone Winter oilseed rape European Central Zone
Plant Growth Regulator Clarification of efficacy data requirements for the authorization of a plant growth regulator in oilseed and turnip rape in the European Northern authorization zone Oilseed and turnip rape European Northern Zone



Zonal maps

The map below displays the zones of comparable climate in the EPPO region as defined in EPPO Standard PP 1/241 Guidance on comparable climates for the purposes of efficacy evaluation trials on plant protection products. Please note that the borders are intentionally broad indicating that there is an area of gradual change in climate between the zones proposed.



The three maps below represent the EPPO climatic zones, the EU authorisation zones according to Regulation (EC) No 1107/2009, and their superimposition. They might be found a useful aid for facilitating discussions on issues regarding trial number and location.






Three zonal maps  

Background paper  –  Bouma E (2005) Development of comparable agroclimatic zones. Bulletin OEPP/EPPO Bulletin 35, 233-238. 



Belgian study on the distribution of crops in Europe

An important consideration when determining the number and location of crop trials is identifying the distribution of crop growing regions. The following study done in 2012 by Mr Pierre Hucorne (CWRA, Belgium) provides useful information to assist research on crop distribution. Please note that the reliability of the data is based on the sources used and crop distribution may change over time. Expert judgement should be applied when conducting such research.


Belgian study on distribution of crops in Europe  



Useful links