Diversity for AFLP and SSR in natural populations of Lotus corniculatus L. from Italy.

Birdsfoot trefoil (Lotus corniculatus L.) is a species native to the Mediterranean basin and one of the most widely distributed perennial forage legumes. It is found in cultivated fields as well as in natural pastures of the Mediterranean and temperate regions of Europe, Asia Minor, North Africa, South and North America, Australia, and New Zealand. It is a potential species for marginal, salty, and degraded areas. The genetic variation present in 11 populations of L. corniculatus collected in natural pastures in Italy was assessed by using four amplified fragment length polymorphisms and five simple sequence repeat (SSR) markers, which were previously identified in L. japonicum. The amount of within-population variation was high, but the among-populations variation was higher, allowing discrimination among accessions. Amplified fragment length polymorphisms and SSRs markers provided an almost equal measure of the variation, although the latter provided a better characterization in terms of F-statistic FST and ρ (estimate of population differentiation in autotetraploids) and indicated that the selfing rate in the species was higher than expected. The matrices of SSR genetic distances and the geographic distances of the collection sites were highly correlated. The information on the genetic structure of the populations is briefly discussed in terms of breeding perspectives.