Submitted to: USDA Industry Cacao Working Group
Publication Type: Proceedings
Publication Acceptance Date: December 1, 2001
Publication Date: N/A
Technical Abstract: The United States Department of Agriculture has begun a program to identify and describe the genetic diversity of living germplasm collections of Theobroma cacao genotypes which are maintained in several international collections scattered throughout Central and South America and the Caribbean Islands. Molecular analysis of these collections has been ongoing using single sequence repeats (SSR) DNA analysis to evaluate the utility of these procedures for DNA fingerprinting. DNA fragments were selectively amplified, labeled with fluorescent dyes, and separated by capillary electrophoresis. DNA fragment patterns were reproducible and consistent within a common genotype, while allowing the differentiation of separate divergent genotypes. Similarity dendrograms were based on the combined cluster analysis of SSR primers selectively amplified with polymerase chain reaction (PCR) technology. Based on this study, 15 primers for SSR markers have been selected as an international standard technique for molecular characterization.