Ring test for black pod resistance

The standardized leaf disc inoculation test will be carried out to evaluate resistance to black pod (Phytophthora spp) at all project sites, except in Ecuador where this disease is not important. This test will also be carried out at one place outside cocoa-producing countries (CIRAD, Montpellier, France) using a range of isolates of the pathogen from a variety of field sites. All tests together can be called the 'Ring Test' for black pod resistance in the project. The main objectives are to compare the stability of the resistance, to verify the repeatability of the test and to analyze possible interactions between host genotypes and pathogen isolates or species. The common aspects of this Ring Test, as carried out in Montpellier, are described hereafter. (Résumé d'auteur)