Cytological study of the yacón (Smallanthus sonchifolius) and the field yacón (Smallanthus macroscyphus)

Abstract

The karyotype and meiosis of Smallanthus sonchifolius (yacón) and Smallanthus macroscyphus (yacón del campo) were studied comparatively to evaluate the relationships between the two species. Karyotypes are predominantly symmetrical in both species, with submetacentric chromosomes in S. sonchifolius and telocentric chromosomes in S. macroscyphus. Taking in account the observed cytological characteristic (chromosome number, karyotipes, and meiotic behaviour) and other traits corresponding to morphological type and growing forms, it is appropriate to support that all of them are consistent with an hybrid origin of S. sonchifolius. It is probable that S. macroscyphus be an ancestor of S. sonchifolius.