Indirect Shoot Regeneration Using 2,4-D Induces Somaclonal Variations in Cinchona officinalis

Cinchona officinalis is an important species from the Andean cloud forest that has a low regeneration rate in natural populations. In vitro regeneration of C. officinalis has been successfully established but somaclonal variation was not evaluated. The regeneration pathway and the number of subcultures on somaclonal variation were evaluated using six ISSR primers that amplified 58 loci of Inter Simple Sequence Repeats (ISSR). A dendrogram based on Jaccard´s genetic distance between the subcultures and the donor plant was produced. The results show that indirect shoot regeneration induces somaclonal variation, in the presence 2,4-Dichlorophenoxyacetic acid (2,4-D) in combination with kinetin and 6-Benzylaminopurine (BAP). In combination with 1-Naphthaleneacetic acid (NAA) or with Indole-3-butyric acid (IBA), BAP produces genetically stable explants. The highest proliferation rate was achieved using BAP and IBA. The present research study suggests avoiding the use of 2,4-D when C. officinalis is propagated for reintroduction and restoration projects.

Keywords:
In vitro regeneration; subcultures; auxin; ISSR