Conservation genetics of small relic populations of silver fir (Abies albaMill.) in the northern Apennines

Abstract

Small and isolated silver fir populations from the Emilian Apennines (northern Italy) were studied to assess their level of genetic variation and their relationship with Alpine populations. We investigated the variability of two chloroplast microsatellites to analyse the within-population genetic variability of four peripheral and fragmented Apennine populations and to determine their phylogenetic relatedness to seven Alpine populations covering the entire distribution of silver fir in the Alps. Haplotypic richness and haplotype diversity as well as the fraction of private haplotypes were lower in Apennine populations, evidencing the genetic impoverishment of these stands. The among-population genetic variability analysis revealed the genetic peculiarity of Apennine populations. Analysis of molecular variance showed that the highest level of the among-population variation occurs between Alpine and Apennine regions. A neighbour-joining dendrogram revealed a distinct Apennine cluster that included the closest Alpine population. Our genetic analysis supports a common origin for Emilian Apennine populations, suggesting that these populations are relicts of past large silver fir populations in the northern Apennines. Our results point to a relevant conservation value for these stands, to be considered in their management.

Comparison of range-wide chloroplast microsatellite and needle trait variation patterns in Pinus mugo Turra (dwarf mountain pine)

“…Evidence of different origins of the Apennine vs. Alpine populations has been reported for other conifers, e.g., for P. sylvestris and Abies alba Mill. (Piovani et al 2010). The remaining populations from the Alps belonged to different genetic clusters (G3 and G4), contrary to what was described by Heuertz et al (2010).…”

Genetic diversity of Italian populationsof Abies alba

“…The APU population is of particular conservation value, since despite its very small size (only a few tens of individuals), it harboured a number of private alleles and showed no evidence of any bottleneck. Valuable populations like this, as pointed out by Piovani et al (2010), require careful management, which should include, for example, the cultivation of local seed. Overall, the diversity patterns revealed in the silver fir populations were consistent with the "rear edge versus leading edge" concept, which emphasizes the importance of peripheral populations for species survival and future adaptation to a changing environment (Hampe & Petit, 2005).…”

“…Most of these populations are thought to be native, although some silver fir planting has been carried out in the past, especially in the northern Apennines. In particular, the populations sampled in MNR (Piovani et al, 2010), APU (Amorfini et al, 2004) and VER (Piovani et al, 2010;Ducci & Proietti, 1997) have been shown to have evolved naturally; in any case, only trees old enough (> 80 years) to have been in place prior to any recent afforestation activity were sampled. The populations from GOU, GOR, CHI, SAL, GBR, VIS, DOS, PAU, VER, ABE, FVP, ARC and GAR have been registered in the Italian National Book of Seed Stands: they were selected on basis of their phenotype and their health status (Morandini & Magini, 1975;Ducci & De Rogatis, 2010).…”

“…The tree is relatively common in the central and eastern parts of the Alps, while its populations in the Apennines tend to be small and somewhat fragmented (Piovani et al, 2010); however, large stands are still be found in a few parts of the Apennines (Ducci et al, 1998). The cultivation of silver fir forests has a long tradition in Italy: the records show that both Franciscan and Benedictine monks were managing stands already 1,000 years ago as far apart as Tuscany in the northern part of the country and Calabria in the south.…”

Investigating adaptive genetic variation in forest trees: a genomic approach to define conservation strategies

“…In conseguenza di ciò, molte popolazioni di specie forestali sono caratterizzate da una elevata marginalità, sia in termini ecologici che puramente geografici (e.g. JuMP e PenuelAS, 2006;ScAlfi et al, 2009;PioVAni et al, 2010;leonArdi et al, 2012;de lAfontAine et al, 2013).…”