The effect of genotype and explant age on somatic embryogenesis of coffee

We demonstrate that embryogenic capacity of coffee (Coffea arabica) depends on the genotype, and that it is a character fixed at the early generations F3 or F4. Therefore, the embryogenic capacity F5 lines can be predicted in a breeding program if it is possible to evaluate the F3 of F4 ancestors, or lines with the same parents on those generations. Regeneration via somatic embryogenesis of genotypes from a C. arabica cv. Caturra by Timor Hybrid cross were evaluated, to determine the effect of the pedigree, month of leaf collection, as well as its interaction with the genotype. Large variations in embryogenic capacity among genotypes were detected with rates ranging from 4.8 to 72.7. There was association between embryogenic response of the progenies and the progenitor from which they proceeded. Significant differences were also found in embryogenic responses depending on the month of leaf explant collection, as well as a significant interaction of genotype by planting month. The results are relevant for breeding and tissue culture purposes of coffee because they will allow speed up of the breeding program and save effort by being able to predict embryogenic capacity of a line, based on the response of either its progenitors or the F3 or F4 lines of the same origin. In addition, high embryogenic capacity lines can be considered directly for genetic transformation or for massive multiplication (bioreactors).