First surveys on genetic variability and structure of field maple (Acer campestre L.) in natural and managed populations in the landscape of central and southern Italy

Four Tuscan populations (central Italy) and three Italian populations from southern Italy (Campania) were sampled to compare their genetic variability and genetic structure. In each geographical area one of the sampled populations is originated naturally in forest and used as a local reference. The remaining populations were originated artificially. Indeed, field maple was traditionally used in Italy to supply fresh fodder to animals in dry summer period as tree twigs or to train up grape trees in the fields edges. This tradition initiated at the time of Etruscans and continued throughout the Roman partitioning of agriculture landscape. Biochemical markers were used to explore variability in the examined populations (5 enzyme systems by 11 loci). Results showed that the main amount of variation is due to the individual component as for most of the scattered hardwoods in Europe and that differentiation among populations for these neutral traits is relatively low. On the other hand, the natural populations in both the geographical areas showed a very high level of panmittic equilibrium, whilst the artificial populations were really distant from this condition showing a high probability of “founder effect”. This could be determined by the former system of self-supplying reproductive material carried out by farmers, based on the wild offspring collection growing around few mother trees. Discussion is focused also on how handling the opportunity given by many hundreds kilometers of lines in the agriculture landscape as a way of managing diversity for this species.