**8. Acknowledgement**

The author gratefully acknowledge the sponsorship provided by the United States Agency for International Development (USAID), United States Department of Agriculture (USDA), and Mars Incorporated for the project on "Assessment of Genetic Diversity in West African Cocoa Collections" conducted within the framework of the Sustainable Tree Crops Program (STCP) of the International Institute of Tropical Agriculture in association with national cocoa research centers including the Cocoa Research Institute of Nigeria (CRIN), Cocoa Research Institute of Ghana (CRIG), National Center for Agronomic Research (CNRA, Cote d'Ivoire) and Institute of Agricultural Research and Development (IRAD, Cameroon).

#### **9. References**

208 Genetic Diversity in Plants

inefficient seed delivery systems in some cases, which are not extending the benefits of improved varieties developed by researchers to farmers. There is a need, therefore, for the establishment of a functional and efficient seed delivery system to facilitate farmers' easy

These studies revealed that research efforts to develop improved varieties over the years have been limited to a narrow range of diversity present in germplasm collections. This, in turn, has limited the gains that would have been made from utilizing useful attributes, such as resistance genes against *Phytophthora* pod rot disease in the Scavina variety and the large bean size of the Iquitos Mixed Calabacillo variety. This information is useful for future cocoa breeding efforts and a guide for future germplasm introduction. This knowledge is also important to enable the development of appropriate breeding strategies to improve planting materials, with particular attention to the integration of available genetic diversity into future cocoa improvement programmes. However, the discontinued use of the Amelonado cocoa by farmers have significant implication for the conservation of this stock, some of which are completely homozygous at all loci used in this study. It is hereby suggested that conservation strategies should be developed to preserve the local Amelonado landraces in

Although useful information have now been obtained on genetic diversity in the major cocoa producing (Cameroon, Cote d'Ivoire, Ghana and Nigeria) West and Central African countries, much information is still needed on the genetic diversity situation in other countries in the region and others such as Eastern and Southern African countries. For instance, information on genetic diversity in Sao Tome & Principe island and Fernando Po (Bioko) in Equatorial Guinea, the earliest places of cocoa introduction in Africa will be useful to determine the sources of many private alleles that were found in farmers accessions but absent in field genebanks. It is also very important to capture the diversity that might be present in order to exploit these for benefits of the ever increasing sophistication of the cocoa market including 'origin' and 'specialty' emphasis of the consumers. It will be very useful if funding could be made available to determine the genetic diversity of cacao types in Madagascar, Malawi, East African countries such as Tanzania and Uganda in addition to the rest West and Central African countries. This is because a thorough knowledge of genetic diversity in on-farm and field genebanks, particularly in an introduced crop species as cacao is crucial to the utilization of the genetic resources available. This will also be important for the sustainability of the global

The author gratefully acknowledge the sponsorship provided by the United States Agency for International Development (USAID), United States Department of Agriculture (USDA), and Mars Incorporated for the project on "Assessment of Genetic Diversity in West African Cocoa Collections" conducted within the framework of the Sustainable Tree Crops Program (STCP) of the International Institute of Tropical Agriculture in association with national cocoa research centers including the Cocoa Research Institute of Nigeria (CRIN), Cocoa Research Institute of Ghana (CRIG), National Center for Agronomic Research (CNRA, Cote d'Ivoire) and Institute of Agricultural Research and Development

access to improved planting materials.

cocoa industry.

**8. Acknowledgement**

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