Examination of the hybrid origin of the wild diploid potato Solanum ruiz-lealii Brucher.

RAIMONDI J. P.; PERALTA I. E.; MASUELLI R. W.; FEINGOLD S.; CAMADRO E. L.

PLANT SYSTEMATICS AND EVOLUTION

SPRINGER WIEN

Lugar: VIENA, AUSTRIA; Año: 2005 vol. 253 p. 33 - 51

0378-2697

The common potato, tetraploid Solanum tuberosum spp. tuberosum L. (tbr), has a narrow genetic base but a large number of related tuber-bearing species that harbor genetic diversity for agronomic characters. The taxonomic status of Solanum ruiz-lealii Bru¨cher (rzl), a diploid species endemic to Mendoza province, Argentina, is controversial. It has been described as a new species of non-hybrid origin and as a natural hybrid between S. kurtzianum Bitt. & Wittm. (ktz) and S. chacoense Bitt. (chc). The hypothesis of the hybrid origin of rzl is examined systematically for the first time by phenetic analyses of morpholog-ical and molecular (SSR markers) data, and cytological analyses of interspecific hybrids. The morphological, cytological and molecular data are congruent, and suggest that rzl is not a recent natural hybrid between the ktz and the chc populations studied but has probably originated by divergence of chc, or by hybridization between chc and another taxon.