Somatic Embryogenesis in Native Peruvian Fine-Flavor Cocoa Genotypes

Cacao genotypes propagation through plant tissue culture represents a strategic approach for establishing a core collection of elite plants to be used as a donor material source, necessary for increasing new planting areas of cacao. This study aimed to evaluate somatic embryo regeneration in ten native fine-aroma cacao genotypes (INDES-06, INDES-11, INDES-14, INDES-32, INDES-52, INDES-53, INDES-63, INDES-64, INDES-66, INDES-70) from the INDES-CES germplasm collection, under in vitro conditions using culture medium supplemented with different concentrations of Thidiazuron (0, 10, and 20 nM). Our results showed an average of 20 and 100% of callogenesis in all genotypes evaluated, but the callus development did not appear after early stages of its induction; however, primary somatic embryos were observed after 42 days after TDZ treatment in the INDES-52, INDES-53, INDES-64, INDES-66, INDES-70 genotypes. The INDES-52 genotype was more responsive to under 20 nM of TDZ, generating an average of 17 embryos per explant. This study contributes to the adaptation and establishment of a protocol for somatic embryo regeneration of fine-flavor cacao genotypes.