Outlines of the cacao selection and breeding programme in san thome

The methods and techniques of cacao selection and breeding are discussed in relation to the problems of the San Thome industry. A general survey of the cacao crop was carried out in order to determine the varieties grown, the range of variability in the local population, disease incidence and cacao quality. Yield was established as the major aim in the cacao breeding program. Vigorous and early bearing genotypes are also desirable. Resistance toPliytophthora palmivora is to be considered at a later stage, when studies of the fungus and its different strains are more advanced to allow for the search of tolerant genotypes. The program includes single plant selection in the local cacao population, introduction of hybrid seed and selected parents, and single and multiple crosses among clones selected locally and abroad. Emphasis is laid on studies on the inheritance of several quantitative characters, such as combilling ability, yielding ability, vigor, and seed size. Incompatibility studies in relation to seed production and interspecific and intergenerie crosses, including studies on the cytological behaviour of the species and their hybrids, are also to be undertaken.