01160nas a2200181   4500008004100000245004400041210004400085260000900129300001200138490000700150520070000157100001600857700001700873700001300890700001600903700001600919856004300935       2007                        eng d00aPresence of Triploids among Oak Species0 aPresence of Triploids among Oak Species  c2007  a959-9640 v993 aBackground and Aims: Polyploids, organisms that have multiple sets of chromosomes, are common in certain plant and animal taxa. However, there are only a few reports of intraspecific ploidy variation within the genus Quercus. The aim of the study was to investigate the suspected ploidy level of two oaks that have unusual microsatellite banding patterns.Methods: Polyploidy was investigated by using microsatellite analysis, stomata length measurements and nuclear DNA content estimation by flow cytometry. Key Results: Each putative triploid tree has patterns of microsatellite variation unexpected for diploid genomes, with up to three alleles at some loci, significantly longer stomata and 11 aDzialuk, A.1 aChybicki, I.1 aWelc, M.1 aliwiska, E.1 aBurczyk, J.  uhttps://quercus.myspecies.info/node/2500526nas a2200157   4500008004100000245011800041210006900159260000900228300001400237490000700251100001900258700001800277700001600295700001400311856004300325       2005                        eng d00aSpecies Distinction in Irish Populations of Quercus petraea and Q. robur: Morphological versus Molecular Analyses0 aSpecies Distinction in Irish Populations of Quercus petraea and   c2005  a1237-12460 v961 aKelleher, C.T.1 aHodkinson, T.1 aDouglas, G.1 aKelly, D.  uhttps://quercus.myspecies.info/node/3302789nas a2200181   4500008004100000245016100041210006900202260000900271300001200280490000700292520215600299100001602455700001802471700001602489700002002505700001802525856006402543       2007                        eng d00aCoincidence of Small-scale Spatial Discontinuities in Leaf Morphology and Nuclear Microsatellite Variation of Quercus petraea and Q. robur in a Mixed Forest0 aCoincidence of Smallscale Spatial Discontinuities in Leaf Morpho  c2007  a713-7220 v993 aBackground and AimsThe taxon complex comprising Quercus petraea and Q. robur shows distinct morphologies and ecological preferences, but mostly low differentiation in various types of molecular markers at a broad spatial range. Local, spatially explicit analyses may reveal patterns induced by microevolutionary processes operating mainly over short distances. However, no attempts have been made to date to explore the potential of spatial analyses combining morphological and genetic data of these oaks. Methods A mixed oak stand was studied to elucidate the small-scale population genetic structure. All adult individuals were classified and putative hybrids were identified using multivariate discrimination analysis of leaf morphological characters. Likewise, all trees were genotyped with five nuclear microsatellites, and a Bayesian assignment method was applied based on maximum likelihood of multilocus genotypes for taxon and putative hybrid classification. Key Results Multivariate analyses of leaf morphological data recognized two groups with few individuals as putative hybrids. These groups were significantly differentiated at the five microsatellites, and genetic taxon assignment coincided well with morphological classification. Furthermore, most putative hybrids were assigned to the taxon found in their spatial neighbourhood. When grouping trees into clusters according to their spatial positions, these clusters were clearly dominated by one taxon. Discontinuities in morphological and genetic distance matrices among these clusters showed high congruence. Conclusions The spatial-genetic analyses and the available literature led to the assumption that reproductive barriers, assortative mating, limited seed dispersal and microsite-induced selection in favour of the locally adapted taxon at the juvenile stage may reinforce taxon-specific spatial aggregation that fosters species separation. Thus, the results tend to support the hypothesis that Q. petraea and Q. robur are distinct taxa which share a recent common ancestry. Occasional hybrids are rarely found in adults owing to selection during establishment of juveniles.1 aGugerli, F.1 aWalser, J.-C.1 aDounavi, K.1 aHolderegger, R.1 aFinkeldey, R.  uhttp://aob.oxfordjournals.org/cgi/content/abstract/99/4/713