Molecular and morphological differentiation among sea, ruderal and cultivated beets

Knowledge of genetic diversity and relationships among Beta vulgaris genetic resources is essential for their conservation and development of breeding populations. In this study, we compared patterns of genetic variability and quantitative morphological data between a sea and a ruderal beet populations, collected on near sites of the Tyrrhenian coast of Italy, and a sugar beet variety. Eight amplified fragment length polymorphism (AFLP) primer-pairs were used for the genetic analysis whereas five traits of the root apparatus were evaluated for the morphological analysis in sixteen-day-old seedlings grown in hydroponics. Clustering analysis based on AFLP markers and root morphological data showed similar patterns of differentiation, in which sea, ruderal and cultivated beets appeared to be genetically distinct groups. A higher level of genetic variability was detected in the sea beet population, which may be due both to the limited gene flow between populations and the highly variable patterns of selection that occur in ecological niches, with respect than the genetic variability observed in the ruderal and cultivated beets. The results of this study revealed the extent of genetic diversity present within undomesticated beet populations that could be valuable in sugar beet improvement.