Location: Sustainable Perennial Crops Laboratory2012 Annual Report
1a. Objectives (from AD-416):
The objective is to identify important fine flavored cacao varieties at the molecular level so that these and related types can be preserved and utilized. The Cooperator is interested in the conservation of fine flavored cacao types that are the basis for the growth of their industry. Various members of the association have the expertise to identify, evaluate and locate fine flavored cacao type from around the world.
1b. Approach (from AD-416):
The Cooperator and its members will identify fine flavored cacao types from around the world and will work with ARS and in-country collaborators/growers to acquire leaf samples for DNA testing. ARS will determine the molecular identification of these varieties so that each type will have a genetic ID that can be used as a reference for that type. The DNA analysis protocols and ID references will be established by ARS and made available to the Cooperator so that other sources of DNA analysis can be acquired for routine analysis. All cacao material and genetic ID data will be managed through Material Transfer Agreements and on completion will be transferred to the International databases along with any additional information that is known about these fine flavored cacao varieties. This information will be used by both ARS and the Cooperator to jointly develop conservation and utilization systems that preserve the unique flavor traits of these varieties. The Cooperator will work with producers and producing countries to develop long-term conservation schemes and increase the production of these unique cacao types though on-farm conservation.
3. Progress Report:
This specific cooperative agreement was set up to provide a mechanism to fund collaborative research on identification and characterization of fine flavored traditional cacao varieties and facilitate their sustainable conservation and utilization. In 2012, a total of 84 traditional cacao varieties collected from Honduras and Nicaragua were analyzed using a new generation of DNA markers called Single Nucleotide Polymorphism (SNP) markers. The study also included 31 types from the international cacao collections to serve as references. This technology unambiguously identified ancient Criollo, Amelonado, Trinitario, and Upper Amazon Forastero populations in the 84 farmer varieties. The results supported the perceived classification of cacao by local farmers and researchers, which was mainly based on morphological traits. The well-known traditional variety “Indio” in this region was identified as an Amelonado. We also found that the variety “Indio” (or Amelonado) made a major contribution to the parentage of the Trinitario type varieties in this region. The present study demonstrates the high efficacy of using a small set of SNP makers as DNA fingerprints for the identification of traditional varieties from farmer fields, and further depicts the diverse origins and parentage in farmer varieties from Mesoamerica. This information thus will be highly useful for conservation and utilization of cacao germplasm from this region.