Exploring the Diversity and Ancestry of Fine-Aroma Cacao from Tumaco, Colombia

The cacao plant, Theobroma cacao, is economically significant, as its beans are essential for chocolate production. Cacao from Tumaco on Colombia’s Pacific coast is renowned for its distinct flavor and aroma, accessing specialty markets. However, production challenges include low yields, inconsistent post-harvest practices, and limited knowledge of local genotypes. To tackle these issues, a research project genetically characterized 25 Tumaco landraces, establishing their phylogenetic relationships using reduced representation libraries (RRL). The analysis yielded 359,950 single nucleotide polymorphisms (SNPs) for Tumaco and identified 38,812 SNPs in common with Colombian National Germplasm Bank genotypes and reference groups. Genetic structure analysis divided Tumaco samples into nine populations, revealing admixtures primarily from the Nacional, Iquitos, Amelonado, and Criollo groups. Some Tumaco samples showed predominant ancestry from the Iquitos group, while others leaned towards the Nacional type, with limited Criollo and Contamana ancestry. No Tumaco landrace exhibited complete ancestry from a single group, suggesting a hybrid origin. These insights into Tumaco’s genetic diversity and structure are essential for improving landraces in Colombia’s Pacific region, contributing to the genetic enhancement of cacao.