MOLECULAR CARACTERIZATION AND IDENTIFICATION OF SACCHARUM COMPLEX CLONES FOR BROADENING THE GENETIC BASE OF SUGARCANE

Resumen

The knowledge about the amount and distribution of the genetic variation among cultivated species and their wild relatives is necessary to improve the efficiency of breeding and genetic conservation programs.
Sugarcane belongs to the Saccharum genus, Andropogoneae Tribe of the Grass family. Six species are included in this genus characterized by a high ploidy level: Saccharum spontaneum L. (2n = 64-112) is a wild highly polymorfic species, Saccharum robustum Brandes & Jeswiet (2n = 60-80) a wild species also, S. officinarum L. (2n = 80) is a high sugar producer, S. barberi Jeswit (2n = 111-120) and S. sinense Roxb. (2n = 81-124) are presumed to be of interspecific origin, involving S. officinarum and S. spontaneum crosses (Sreenivasan et al., 1987). On the other hand, S. edule is considering as a marginal form of sugarcane, cultivated as vegetable. A major limitation of sugarcane breeding is its reduced genetic base, modern cultivars being descendants of a few ancestors or foundation clones. Their cytoplasmic origins are more limited and are mainly represented by 3-5 Saccharum officinarum clones.