Geographic distribution, conservation, and genomic resources of cacao Theobroma cacao L

• Published in: Crop science 2023-07, Vol.63 (4), p.1750-1778
• Main Authors: Nieves‐Orduña, Helmuth E., Krutovsky, Konstantin V., Gailing, Oliver
• Format: Article
• Language: English
• ISSN: 0011-183X; 1435-0653
• DOI: 10.1002/csc2.20959

The cacao tree, Theobroma cacao L., is cultivated in the tropics, mainly in agroforestry systems, to produce seeds, the valuable raw material for the chocolate industry. Thus, the conservation and use of cacao genetic resources in breeding programs to increase yield and improve quality and disease resistance are vital for the global cacao economy. We review three important topics of cacao genetics essential for sustainable production and crop improvement: (1) geographic distribution of wild cacao populations and geographic patterns of their genetic variation in Amazonia; (2) conservation, availability, and use of cacao genetic resources in cultivar development; (3) genetic basis of agronomic traits, available molecular genetic markers, and genomic resources and their application for cacao improvement. We also highlight critical research areas needed to achieve sustainable cacao cultivation. Core Ideas The geographic distribution of genetic variation of wild cacao pinpoints new sampling areas for germplasm collections. The natural habitat of cacao is under threat due to current and projected deforestation in Amazonia. Germplasm collections can benefit from genotype identity and characterization of agronomic traits based on available SNP markers. The wide cacao genetic diversity can be tested against different fungal strains to identify new sources of disease resistance. Genome‐wide SNP data in combination with standard phenotyping of agronomic traits can be exploited to identify relevant genotypes for breeding.