Variability in cacao selected by producers for resistance to witches´ broom based on microsatellite markers
Alessandra S G Faleiro, Fábio G Faleiro, Uilson V Lopes, Gilson R P Melo, Wilson Reis Monteiro, Milton Macoto Yamada, Rita C S Bahia, and Ronan X Corrêa
This study aimed at a microsatellite marker-based assessment of the genetic variability of 30 accessions of Theobroma cacao selected for resistance to witches´ broom on commercial plantations in the cocoa region of Bahia State and to compare them with traditional sources of resistance to witches´ broom (SCA-6 and IMC-67) and other parents (ICS-1 and SIC-19) used in the breeding program of the Cocoa Research Center (CEPEC). Sixteen pairs of specific primers for microsatellite loci were used, generating 64 alleles. The genetic distance between the analyzed accessions ranged from 0.13 to 0.71 and the heterozygosis levels from 23 to 76%. The cluster analyses grouped 18 accessions (60%) together with SCA-6. Accessions selected on farms for their high levels of resistance to witches´ broom, good agronomic traits, which are genetically distant from SCA-6, have a high potential for the breeding program or even for direct recommendation to farmers.