c8.12.12 – Genetic diversity within a sympatric white oak woody community (Quercus spp.)

Antonecchia G, Viscosi V, Gerber S, Leger P, Lepais O, Scippa GS, Fortini P

Collocazione: c8.12.12 – Tipo Comunicazione: Poster
8° Congresso SISEF *
Sessione 12: “Poster” *

Contatto: Gaby Antonecchia (gaby.antonecchia@studenti.unimol.it)

Abstract: Because of the characteristic of oak species to intercross, gene flow in genus Quercus has been intensively studied and the hybridization represents a common phenomenon that frequently co-occurs in mixed stands. It’s well known that gene flow can cause an increasing of intermediate forms and may also bring novel adaptations in the recipient species (Curtu et al. 2009; Lepais et al. 2010; Lepais & Gerber, 2011). In this study, genetic differentiation of molecular traits, within a natural mixed forest composed by three sympatric white oak species (Quercus frainetto Ten., Q. petraea Liebl. Matt. e Q. pubescens Willd.) was studied by using of nuclear microsatellites EST-SSRs. The studied oak community is located in a limited protected area (SIC IT7222295, Habitat Directive 42/96 CE) with a natural vegetation coverage made up by the 84.8% of deciduous mixed oaks woods (Corine Land Cover 3112). In detail, a total of 268 oak trees were sampled in 9 stands (50 x 50 meters) and genotyped at 12 microsatellite markers, using a PCR 12-plex protocol (Durand et al., 2010; Guichoux et al, 2011). Bayesian cluster analysis, computed without a priori information, individuated three significantly differentiated genotypes, which corresponded to the three morphological species. Moreover, the percentage of hybrids varied considerably in the area of study, ranging from 3.33% to 36.67% per stand. All nuclear markers resulted 100% polymorphic with a number of alleles, which varied from 3, in Q. frainetto, to 14 in Q. petraea with an average of 8.611 alleles per locus. Gerarchical partition of genetic variation (AMOVA) revealed that the percentage of molecular variance was mainly distributed in the species (87%), while a smaller, but significant, proportion was among species (13% of total variance; Fst=0.125; p

Parole chiave: Gene Flow, Hybridization, Q.frainetto, Q.petraea, Q.pubescens, Est-ssrs

Citazione: Antonecchia G, Viscosi V, Gerber S, Leger P, Lepais O, Scippa GS, Fortini P (2011). Genetic diversity within a sympatric white oak woody community (Quercus spp.) . 8° Congresso Nazionale SISEF, Rende (CS), 04 – 07 Ott 2011, Contributo no. #c8.12.12