RAPD analysis of the genetic diversity of Theobroma cacao L. from a population of the Ecuadorian Coast

Abstract

In this study, RAPD (Random Amplification of Polymorphic DNA) analysis was used to estimate the genetic diversity and relationships of 20 accessions of Theobroma cacaoL. National variety on the farm (the minibus) located in the Tenguel parish, Guayas province. The plants were selected with criteria of productivity, resistance, and susceptibility to diseases caused by fungi such as Ceratocystis fimbriata, Moniliophtora roreri, and Crinipelis perniciosa. 14 primers were used, nine of them amplified, generating 67 bands of which 59 (88%) were polymorphic. The results indicate the formation of two groups of accessions A and B. Group A includes two accessions while in B there are 18, divided into two subgroups B1 and B2. The B1 subgroup includes the accession (L-22-H-40) and the B2 subgroup includes the accessions that have productivity characteristics. The highest level of genetic diversity was obtained with the starters OPC 04 (0.80), OPC 07 (0.82) and the lowest was OPC 01 (0.37). The accessions (L-22-H-40; O.75; L-34-H-07;0.86) and (L-42-H-60; 0.72) had quite large levels of genetic variability, reaching the lowest values shown by the accessions (L-26-H-64; O.48) and (L-23-H63; O.47). The value of the total diversity (Ht) obtained for the 20 accessions of T.cacao L. RAPD was 0.636