01945nas a2200133   4500008004100000245005700041210005700098260000900155300001400164490000700178520156700185100001601752856004301768       1993                        eng d00aGene diversity in natural populations of oak species0 aGene diversity in natural populations of oak species  c1993  a186s-202s0 v503 aThis contribution reviews studies of nuclear and organelle gene diversity in oak species. Studies of allozymes were reported for 33 species belonging to the sections Erythrobalanus, Lepidobalanus and Mesobalanus of the genus Quercus. The extent and organization of gene diversity were investigated at 3 hierarchical levels: complex, species and population. Total diversity at the species and population level varies greatly among species (from 0.06 to 0.40). The range of variation among species is as large as that observed in other plant genera. Life history characteristics and evolutionary history are the main explanations for these results. Species with large and continuous distributions such as Q petraea and Q rubra exhibit high levels of gene diversity. Within a complex, most of the nuclear gene diversity is distributed within populations (74%). The remaining diversity is mainly due to species differentiation (23%), while the between-population component is low (3%). Organelle gene diversity has been investigated recently in 2 species complexes in the section Lepidobalanus (one in North America and one in Europe). Compared to nuclear genes, organelle gene diversity is strikingly different. Contributions of within-stand variation, species differentiation and population differentiation to total diversity, are respectively 13%, 11 % and 76%. Trees of a given population generally share the same chloroplast genome. Moreover, trees of different species (with reported introgression) occupying the same stand exhibit a high degree of similarity.1 aPetit, R.J.  uhttps://quercus.myspecies.info/node/8101212nas a2200181   4500008004100000245008500041210006900126260000900195300001000204490000600214520068100220100002200901700001800923700001500941700001500956700001600971856004300987       2003                        eng d00aA set of primers for the amplification of chloroplast microsatellites in Quercus0 aset of primers for the amplification of chloroplast microsatelli  c2003  a24-270 v33 aThe increase in demand for the certification of oak seed lots, as well as control of the geographicalorigin of oak wood, has led us to develop powerful genetic markers permitting us to discriminate among provenance regions. With the aim of detecting new chloroplast variants, we have identified 17 potential cpSSRs motifs from available oak sequences and tested their variability among French oak populations. Six loci were polymorphic at the intraspecific level in Quercus petraea and Q. robur. Moreover, conservation of the primer pairs was checked on a set of 21 forest tree species and they were all shown to work well on several Quercus species, and even within Fagacaea.1 aDEGUILLOUX, M.-F.1 a-LAP, DUMOLIN1 aGIELLY, L.1 aGRIVET, D.1 aPetit, R.J.  uhttps://quercus.myspecies.info/node/4501439nas a2200325   4500008004100000245009600041210006900137260000900206300001400215490000800229520059800237653000800835653003100843653001700874653001200891653002500903100000500928700001600933700001400949700001700963700001400980700001700994700000501011700000501016700000501021700001501026700001301041700001601054856004301070       2002                        eng d00aChloroplast DNA variation of white oaks in the northern Balkans and in the Carpathian Basin0 aChloroplast DNA variation of white oaks in the northern Balkans   c2002  a197 - 2090 v1563 aA total of 1113 oak trees from 222 populations originating from eight countries (Austria, Bosnia-Herzegovina, Croatia, Hungary, Romania, Slovakia, Slovenia, Yugoslavia) were sampled in natural populations or in provenance tests. The sampled trees belong to four different species (Quercus robur, Quercus petraea, Quercus pubescens, Quercus frainetto) and to several putative subspecies. Variation at four chloroplast DNA (cpDNA) fragments was studied using restriction enzymes, resulting in the detection of 12 haplotypes. One haplotype was present in 36% of the trees, and six were found in 610aPCR10aPostglacial recolonisation10aQuercus spp.10aRefugia10aSpecies distribution1 a1 aPopescu, F.1 aSlade, D.1 aCsaikl, U.M.1 aLesur, I.1 aBorovics, A.1 a1 a1 a1 aBrewer, S.1 aBurg, K.1 aPetit, R.J.  uhttps://quercus.myspecies.info/node/4700495nas a2200145   4500008004100000245012100041210006900162260000900231300001400240490000700254100001400261700001500275700001600290856004300306       2006                        eng d00aShared alleles in sympatric oaks: recurrent gene flow is a more parsimonious explanation than ancestral polymorphism0 aShared alleles in sympatric oaks recurrent gene flow is a more p  c2006  a2007-20120 v151 aLexer, C.1 aKremer, A.1 aPetit, R.J.  uhttps://quercus.myspecies.info/node/2902180nas a2200181   4500008004100000245010200041210006900143260000900212300001200221490000700233520159600240100001601836700001701852700001401869700001601883700001501899856008401914       2005                        eng d00aChloroplast DNA variation of Quercus rubra L. in North America and comparison with other Fagaceae0 aChloroplast DNA variation of Quercus rubra L in North America an  c2005  a513-5240 v143 aAbstract Quercus rubra is one of the most important timber and ornamental tree species from eastern North America. It is a widespread species growing under variable ecological conditions. Chloroplast DNA variation was studied by PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) in 290 individuals from 66 populations sampled throughout the natural range. A total of 12 haplotypes were detected, with one found in 75% of the trees. Population differentiation is relatively low (GST = 0.46), even when similarities between haplotypes are taken into account (NST = 0.50), pointing to a weak phylogeographical structure. Furthermore, no spatial structure of genetic diversity could be detected. The genetic differentiation increased northwards, reflecting the postglacial history of Q. rubra. The unusual aspect of this study was the low level of chloroplast DNA genetic differentiation in Q. rubra compared to that typically observed in other oak species. Palynological evidence indicates that during the last glacial maximum, Q. rubra had one major distribution range with populations located relatively far to the north, resulting in only modest movement northwards when climate improved, whereas European white oaks were largely restricted to the southern European peninsulas and experienced extensive movements during the postglacial period. The contrasted geographical features and levels of tree species richness of both continents might further explain why congeneric species sharing similar life history traits have genetic structures that are so different.1 aMagni, C.R.1 aDucousso, A.1 aCaron, H.1 aPetit, R.J.1 aKremer, A.  uhttp://www.blackwell-synergy.com/links/doi/10.1111/j.1365-294X.2005.02400.x/abs02338nas a2200217   4500008004100000245007000041210006900111260000900180300001400189490000700203520173100210653001201941100001501953700001601968700001701984700001802001700001602019700001502035700001502050856005502065       2009                        eng d00aSpecies relative abundance and direction of introgression in oaks0 aSpecies relative abundance and direction of introgression in oak  c2009  a2228-22420 v183 aSuccessful hybridisation and subsequent introgression lead to the transfer of genetic material across species boundaries. In this process, species relative abundance can play a significant role. If one species is less abundant than the other, its females will receive many heterospecific gametes, increasing mate-recognition errors and thus hybridisation rate. Moreover, first-generation hybrids will also more likely mate with the more abundant species, leading to asymmetric introgression. These predictions have important fundamental consequences, especially during biological invasions or when a rare species threatened by extinction is surrounded by individuals from a related species. However, experimental tests in nature of the importance of the relative abundance of each species on hybridisation dynamics remain scarce. We assess here the impact of species relative abundance on hybridisation dynamics among four species from the European white oak species complex. A total of 2107 oak trees were genotyped at 10 microsatellite markers and Bayesian clustering methods were used to identify reference trees of each species. We then used these reference trees to simulate purebred and hybrid genotypes to determine optimal threshold for genetic assignment. With this approach, we found widespread evidence of hybridisation between all studied oak species, with high occurrence of hybrids, varying from 11% to 31% according to stand and sampling strategies. This finding suggests that hybridisation is a common phenomenon that plays a significant role in evolution of this oak species complex. In addition, we demonstrate a strong impact of species abundance on both hybridisation rate and introgression directionality.10aQuercus1 aLepais, O.1 aPetit, R.J.1 aGuichoux, E.1 aLavabre, J.E.1 aAlberto, F.1 aKremer, A.1 aGerber, S.  uhttp://dx.doi.org/10.1111/j.1365-294X.2009.04137.x