02861nas a2200433   4500008004100000245015900041210006900200260000900269300001400278490000700292520150400299653001601803653002301819653002101842653001801863653001201881653001901893653003701912653004401949653002801993653001402021653002002035653001302055653001202068653004402080653001702124653003802141653003002179653001802209653001902227653002002246653002402266653002002290100001902310700002002329700001702349700001802366856004302384       1993                        eng d00aIsozyme variation in oaks of the Apostle Islands in Wisconsin: Genetic structure and levels of inbreeding in Quercus rubra and Q. ellipsoidalis (Fagaceae)0 aIsozyme variation in oaks of the Apostle Islands in Wisconsin Ge  c1993  a1349-13570 v803 aIsozyme variability was examined in populations representing the red oak complex (Quercus subg. Erythrobalanus) on an island archipelago and adjoining peninsula in Lake Superior, near Bayfield, Wisconsin. A concomitant study of morphometric variation described in the companion manuscript, revealed a continuum in leaf morphology extending from an interior mainland site to the outermost island. The existence of this clinal variation presented an ideal opportunity to examine the genetic structure of a hybrid population along with the putative progenitor species. Dormant leaf bud samples were collected from specimens of Quercus rubra L., Q. ellipsoidalis Hill, and their putative hybrids from three islands and two locations on the peninsula. Acorns were collected from some of these same trees from one peninsula location and two islands. Twelve putative enzyme loci from six enzyme systems were analyzed. Allele frequency data indicated little differentiation between populations. Mean F-ST values for the adult trees and acorns were 0.042 and 0.020. Genetic identities according to Nei ranged from 0.958 to 0.999. Despite these high levels of genetic similarity, the populations appeared to be highly inbred as indicated by positive mean F-IT values of 0.183 and 0.373 for the adult trees and acorns. Estimates of migration rate per generation (Nm) for the adult trees was 5.70, a value that is low when compared to estimates for other plant species with similar life history characteristics.10a-Biophysics10a[26070-] Fagaceae-10aALLELE-FREQUENCY10aAngiospermae-10aDicots-10aDicotyledones-10aEcology-: Environmental-Sciences10aEnzymology-: Biochemistry-and-Molecular10aFagaceae-: Angiosperms-10aGenetics-10aNearctic-region10aPlantae-10aPlants-10aPopulation-Genetics: Population-Studies10aPOPULATIONS-10aQuercus-ellipsoidalis (Fagaceae-)10aQuercus-rubra (Fagaceae-)10aReproduction-10aSpermatophyta-10aSpermatophytes-10aUSA-: North-America10aVascular-Plants1 aHokanson, S.C.1 aIsebrands, J.G.1 aJensen, R.J.1 aHancock, J.F.  uhttps://quercus.myspecies.info/node/8202888nas a2200157   4500008004100000245009900041210006900140300001000209490000700219520239600226100001702622700001502639700001502654700001802669856004302687       1997                        eng d00aPopulation structure, genetic diversity, and clone formation in Quercus chrysolepis (Fagaceae)0 aPopulation structure genetic diversity and clone formation in Qu  a1553-0 v843 aStands of canyon live oak (Quercus chrysolepis, Fagaceae) are maintained for fuelwood, fire management, recreation, and as habitat for wildlife. Information about the link between the oak’s reproductive ecology and its extent of genetic diversity is important in developing land management policies that will maintain the long-term viability of populations. Basal sprouting is the primary means of reproduction following fire or cutting, and stands frequently include groups of visibly connected trees in a clustered distribution that suggests cloning. We determined the extent to which clusters of trees were clonal and defined the spatial pattern and diversity of genotypes for six populations across nearly the entire east-west extent of the San Bernardino Mountains in southern California. We mapped over 100 trees at each of five sites and genotyped each tree for allozymes at seven polymorphic loci. We identified clones using these multilocus genotypes and detected an average of 34.4 ± 7.3 (SD) clones per site, most of which had unique genotypes. In general, clustered trees belong to single clones and most clones consist of few trees (mean = 3.4 ± 0.6 trees per clone). However, clone size increased significantly with increased individual heterozygosity, suggesting that selection may favor highly heterozygous clones. Clonal diversity and evenness were high relative to reports for most other clonal species; an average of 97% of clones had distinct genotypes, and Simpson’s index of diversity averaged 0.95 ± 0.02. Population genetic analyses of 319 clones from six sites revealed high genetic diversity within sites (mean HS = 0.443). Only a small proportion of the total genetic diversity was explained by variation among sites (mean GST = 0.018), which is consistent with high gene flow among sites (Nm = 9.5). We found no significant substructure among plots within sites, and fixation indices within sites were generally small, suggesting that either little inbreeding occurs, and/or few inbred progeny survive. However, spatial autocorrelation analysis of clones indicated fine-scale genetic structure at distances under 4 m, possibly due to limited seed dispersal. Our data suggest that guidelines for seed collection of canyon live oak for use in restoration can be specified in a manner similar to that recommended for conifer species within the region studied.1 aMontalvo, AM1 aConard, SG1 aConkle, MT1 aHodgskiss, PD  uhttps://quercus.myspecies.info/node/7202212nas a2200205   4500008004100000245007900041210006900120260000900189300001400198490000700212520162300219100001601842700001401858700001601872700001501888700001601903700001501919700001501934856005701949       2002                        eng d00aLandscape-level spatial genetic structure in Quercus acutissima (Fagaceae)0 aLandscapelevel spatial genetic structure in Quercus acutissima F  c2002  a1229-12360 v893 aQuercus acutissima (Fagaceae), a deciduous broad-leaved tree, is an important forest element in hillsides of South Korea. We used allozyme loci, Wright’s F statistics, and multilocus spatial autocorrelation statistics to examine the distribution of genetic diversity within and among three local populations and the spatial genetic structure at a landscape scale (15 ha, 250 x 600 m) on Oenaro Island, South Korea. Levels of genetic diversity in Q. acutissima populations were comparable to mean values for other oak species. A moderate but significant deficit of heterozygotes (mean FIS = 0.069) was detected within local populations and low but significant differentiation was observed among populations (FST = 0.010). Spatial autocorrelation analyses revealed little evidence of significant genetic structure at spatial scales of 100-120 m. The failure to detect genetic structure within populations may be due to intraspecific competition or random mortality among saplings, resulting in extensive thinning within maternal half-sib groups. Alternatively, low genetic differentiation at the landscape scale indicates substantial gene flow among local populations. Although wind-borne pollen may be the primary source of gene flow in Q. acutissima, these results suggest that acorn movement by animals may be more extensive than previously anticipated. Comparison of these genetic data for Oenaro Island with a disturbed isolated inland population suggests that population-to-population differences in internal genetic structure may be influenced by local variation in regeneration environment (e.g., disturbance).1 aChung, M.Y.1 aNason, J.1 aChung, M.G.1 aKim, K.-J.1 aPark, C.-W.1 aSun, B.-Y.1 aPak, J.-H.  uhttp://www.amjbot.org/cgi/content/abstract/89/8/122901878nas a2200157   4500008004100000245012900041210006900170260000900239300001400248490000700262520134300269100001601612700001701628700001701645856005801662       2002                        eng d00aLimited hybridization between Quercus lobata and Quercus douglasii (Fagaceae) in a mixed stand in central coastal California0 aLimited hybridization between Quercus lobata and Quercus douglas  c2002  a1792-17980 v893 aMany oak species are interfertile, and morphological and genetic evidence for hybridization is widespread. Here we use DNA microsatellite markers to characterize hybridization between two closely related oak species in a mixed stand in central coastal California, Quercus lobata (valley oak) and Q. douglasii (blue oak) (Fagaceae). Genotypes from four microsatellite loci indicate that many alleles are shared between the two species. However, each species harbors unique alleles, and allele frequencies differ significantly. A Bayesian analysis of genetic structure in the stand identified two highly differentiated genetic clusters, essentially corresponding to species assignment based on morphology. Data from the four loci were sufficient to assign all 135 trees to one of the two species. In addition, five putative hybrid individuals having intermediate morphologies could be assigned genetically to one or the other species, and all but one had low probability of hybrid ancestry. Overally, only six (4.6%) trees showed >0.05 probability of hybrid ancestry, in all cases their probabilities for nonhybrid ancestry were substantially higher. We conclude that adult hybrids of Q. douglasii x Q. lobata are rare at this site and plasticity in morphological characters may lead to overestimates of hybridization among Quercus species.1 aCraft, K.J.1 aAshley, M.V.1 aKoenig, W.D.  uhttp://www.amjbot.org/cgi/content/abstract/89/11/179201890nas a2200169   4500008004100000245020000041210006900241260000900310300001200319490000700331520126300338100001701601700001601618700001301634700001701647856005601664       2003                        eng d00aDifferentiation and hybridization between Quercus crispula and Q. dentata (Fagaceae): insights from morphological traits, amplified fragment length polymorphism markers, and leafminer composition0 aDifferentiation and hybridization between Quercus crispula and Q  c2003  a769-7760 v903 aQuercus crispula and Q. dentata (Fagaceae) are dominant members of cool-temperate forests of Japan and are assumed to hybridize in nature. To characterize and discriminate these two species and their hybrids, we carried out multivariate analysis using several morphological traits and principal coordinate analysis using molecular (amplified fragment length polymorphism [AFLP]) data. Further, we examined the composition of Phyllonorycter species (leafmining insects) on individuals from a mixed forest. Morphological traits and Phyllonorycter composition differ enough in these two oak species to be useful for identification of species and hybrids. AFLP data, however, are less informative because the degree of molecular differentiation between the two species is low. Nine out of 105 individuals from a mixed stand had intermediate morphologies according to the multivariate analysis, and eight out of the nine individuals had intermediate Phyllonorycter composition in either one or both of the two study years. These eight individuals were tentatively assigned as hybrids or backcross individuals, and the remaining individual with intermediate morphologies was assigned as Q. dentata according to its Phyllonorycter composition and the AFLP analysis.1 aIshida, T.A.1 aHattori, K.1 aSato, H.1 aKimura, M.T.  uhttp://www.amjbot.org/cgi/content/abstract/90/5/76902704nas a2200469   4500008004100000245010800041210006900149260000900218300001200227490000700239520130300246653002601549653002301575653001801598653001601616653003801632653002201670653002601692653001201718653001901730653002801749653001401777653002401791653004101815653002001856653001801876653001301894653001201907653003301919653004101952653003901993653001902032653002002051653002002071653002102091100001502112700001502127700001602142700001702158700001602175856004302191       2005                        eng d00aGene flow and fine-scale genetic structure in a wind-pollinated tree species Quercus lobata (Fagaceaee)0 aGene flow and finescale genetic structure in a windpollinated tr  c2005  a252-2610 v923 aCalifornia Valley oak (Quercus lobata), one of the state’s most distinctive oak species, has experienced serious demographic attrition since the 19th century, due to human activities. Recent estimates of pollen dispersal suggest a small reproductive neighborhood. Whether small neighborhood size is a recent phenomenon, a consequence of reduced gene flow caused by demographic changes, or whether it has been historically restricted, remains unclear. To examine this question, we have characterized the spatial genetic structure of N = 191 Q. lobata individuals, spread over an area of 230 ha, using eight microsatellite loci. The observed autocorrelogram suggests an historical standard deviation of gene flow distance of about 350 m per generation, higher than contemporary pollen dispersal estimates. To determine whether our estimates were affected by strong prevailing winds from the west-northwest, we developed and utilized a novel anisotropic autocorrelation analysis. We detected no more than a hint of anisotropy, and we concluded that adult spatial structure is indicative of strong historical signature of "isolation by distance." This historical estimate provides a useful reference value against which to gauge the future gene flow consequences of ongoing anthropogenic disturbance.10a-Molecular-Biophysics10a[26070-] Fagaceae-10aAngiospermae-10aanisotropy-10aBiogeography-: Population-Studies10aCalifornia-: USA-10ademographic-attrition10aDicots-10aDicotyledones-10aFagaceae-: Angiosperms-10agene-flow10amicrosatellite-loci10aMolecular-Genetics: Biochemistry-and10aNearctic-region10aNorth-America10aPlantae-10aPlants-10apollen-: reproductive-system10aQuercus-lobata (Fagaceae-): species-10aReproductive-System: Reproduction-10aSpermatophyta-10aSpermatophytes-10aVascular-Plants10awind-pollination1 aDutech, C.1 aSork, V.L.1 aIrwin, A.J.1 aSmouse, P.E.1 aDavis, F.W.  uhttps://quercus.myspecies.info/node/3201996nas a2200169   4500008004100000245012500041210006900166260000900235300001200244490000700256520145500263100000501718700001601723700001701739700001401756856005601770       2004                        eng d00aMorphological and RAPD analysis of hybridization between Quercus affinis and Q. laurina (fagaceae), two Mexican red oaks0 aMorphological and RAPD analysis of hybridization between Quercus  c2004  a401-4090 v913 aQuercus affinis and Q. laurina are two closely related Mexican red oaks with partially overlapping distributions. Within the area of overlap, there are localities where morphological intergradation occurs. A previous hypothesis explained this pattern as a result of secondary contact between the two species, followed by hybridization and introgression. This possibility was analyzed here by examining foliar and genetic variation in 16 localities situated along a macrogeographic gradient, which included morphologically representative populations of both species and populations from within the area of overlap. Maximum-likelihood hybrid index scores calculated from nine semi-diagnostic RAPD markers indicated a shift in the genetic composition of populations from one species to the other along the macrogeographic gradient, with genetically intermediate populations situated in the area of overlap. Foliar variation followed a partially congruent pattern, but Q. laurina-like morphology predominated in some of the genetically intermediate populations. There were several instances of correlated frequency changeovers of single RAPD markers and morphological characters along the macrogeographic gradient and a few cases of markedly parallel patterns between markers. The results were interpreted as consistent with a hypothesis of secondary contact between the two oak species that has resulted in some differential introgression among markers.1 a1 aArias, D.M.1 aValencia, S.1 aOyama, K.  uhttp://www.amjbot.org/cgi/content/abstract/91/3/40101908nas a2200145   4500008004100000245014600041210006900187260000900256300001400265490000700279520138000286100002301666700001601689856005701705       2009                        eng d00aMolecular, morphological, and ecological niche differentiation of sympatric sister oak species, Quercus virginiana and Q. geminata (Fagaceae)0 aMolecular morphological and ecological niche differentiation of   c2009  a1690-17020 v963 aThe genus Quercus (the oaks) is notorious for interspecific hybrization, generating questions about the mechanisms that permit coexistence of closely related species. Two sister oak species, Quercus virginiana and Q. geminata, occur in sympatry in Florida and throughout the southeastern United States. In 11 sites from northern and southeastern regions of Florida, we used a leaf-based morphological index to identify individuals to species. Eleven nuclear microsatellite markers significantly differentiated between the species with a high correspondence between molecular and morphological typing of specimens. Nevertheless, Bayesian clustering analysis indicates interspecific gene flow, and six of 109 individuals had mixed ancestry. The identity of several individuals also was mismatched using molecular markers and morphological characters. In a common environment, the two species performed differently in terms of photosynthetic performance and growth, corresponding to their divergent ecological niches with respect to soil moisture and other edaphic properties. Our data support earlier hypotheses that divergence in flowering time causes assortative mating, allowing these ecologically distinct sister species to occur in sympatry. Limited gene flow that permits ecological differentiation helps to explain the overdispersion of oak species in local communities.1 aCavender-Bares, J.1 aPahlich, A.  uhttp://www.amjbot.org/cgi/content/abstract/96/9/1690