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Warm‐edge populations, that is, those usually small and isolated populations at the boundary of species maximum temperature range limit, are of particular scientific and conservation interest. This is especially the case for those that have long been geographically isolated, possibly through multiple glaciations, as they can contribute significantly to species' overall genetic diversity. However, distinguishing between glacial relict and more recently established warm‐edge populations is difficult especially in the absence of a continuous fossil record. In this study, we investigate the origin of anomalously low‐elevation warm‐edge populations of the dominant cool temperate Japanese tree Fagus crenata in the northeast Kanto (NEK) region. We sought to determine whether these populations are glacial relicts or, rather, were established via dispersal in the Holocene using chloroplast and nuclear genetic data, species distribution modeling and comparison with populations in a well‐established glacial refugia (south‐central Kyushu [SCK]) and of mid‐late Holocene age (southern Hokkaido [SH]). Whole chloroplast genome "mining" revealed a similar amount of haplotype diversity in NEK and SCK while there was no chloroplast variation in SH. Populations in NEK, particularly the lowest elevation sites, harbored unique haplotypes providing evidence for their persistence since the Last Glacial Maximum as supported by species distribution models under two of three general circulation models. NEK populations also lacked the genetic signatures of recent expansion that characterize the most northern‐edge populations in SH. We conclude that warm‐edge populations in NEK are most likely relicts of glacial refugia and should be given high priority for conservation. [ABSTRACT FROM AUTHOR]

In plant populations, limited seed dispersal may generate the aggregation of related individuals, which is referred to as spatial genetic structure (SGS). If short-distance pollination frequently occurs in populations with SGS, it may lead to frequent mating between related individuals (biparental inbreeding). In this study, we examined patterns of pollen dispersal and inbreeding under such conditions in a population of the wind-pollinated tree species Fagus crenata Blume using microsatellite analyses of adult trees and dispersed seeds. The population showed weak but significant SGS and the pollen dispersal in the population involved a combination of distance-dependent (largely short-range) dispersion at the local scale and long-distance transport. Although SGS and distance-dependent pollination co-occurred, individual inbreeding coefficients for both adults and seeds were almost zero, suggesting that mating generating sound seeds was genetically random with little or no inbreeding, probably because of the weak SGS, long-distance pollen dispersal, and postpollination mechanisms including self-incompatibility and inbreeding depression. The production of sound seeds through genetically random mating may be important for maintaining F. crenata populations because the resulting seedlings may be less affected by inbreeding depression than those resulting from the mating of related individuals. Key words: dispersal kernel, Fagus crenata, inbreeding coefficient, outcrossing rate, paternity analysis, wind pollination. Resume: Dans les populations vegetales, la dispersion limitee des graines peut generer une agregation des individus apparentes, phenomene que l'on appelle structure spatiale genetique (SSG). Si la pollinisation sur de courtes distances survient frequemment dans les populations avec SSG, ceci peut mener a un croisement frequent entre des individus apparentes (endogamie biparentale). Dans cette etude, les auteurs ont examine les patrons de dispersion du pollen et l'endogamie sous de telles conditions chez une population de Fagus crenata Blume, une espece d'arbres a pollinisation anemophile, a l'aide d'analyses de microsatellites des arbres adultes et des graines dispersees. La population presentait une SSG faible mais significative, et la dispersion du pollen dans la population impliquait la combinaison d'une dispersion en fonction de la distance (principalement de courte distance) a l'echelle locale et d'un transport de longue distance. Meme si la SSG et la pollinisation en fonction de la distance survenaient conjointement, les coefficients individuels d'endogamie des adultes et des graines etaient presque de zero, suggerant que le croisement generant des graines saines etait genetiquement aleatoire avec peu ou pas d'endogamie, probablement a cause de la faible SSG, de la dispersion du pollen sur une longue distance et des mecanismes post-pollinisation incluant l'auto-incompatibilite et la depression endogamique. La production de graines saines au moyen du croisement genetiquement aleatoire peut etre importante pour maintenir les populations de F. crenata car les semis resultants peuvent etre moins affectes par la depression endogamique que ceux qui resultent du croisement d'individus apparentes. [Traduit par la Redaction] Mots-cles : dispersion des grains, Fagus crenata, coefficient d'endogamie, taux de croisement eloigne, analyse de paternite, pollinisation anemophile., Introduction Gene dispersal via seeds and pollen strongly influences the genetic diversity and structure of plant populations. Genetic differentiation among populations is reduced by gene dispersal (i.e., gene flow) even [...]

In clonal plants, ramets connected within a genet can share resources through clonal integration, and clonal integration often facilitates the growth and survival of young ramets. However, in dioecious plants, it is not fully understood whether female and male genets differ in their integration patterns affecting the demographic processes. To test between-sex differences in the demographic process in relation to clonal integration, we conducted a long-term census for the dioecious sprouting shrub Lindera triloba (Sieb. et Zucc.) Blume. In an old-growth forest, we selected 73 female and 82 male genets, and the recruitment, growth, and mortality of ramets within those genets were monitored over six years. Ramet recruitment was greater in males than in females, whereas ramet growth and survival rates did not differ, on average, between sexes. Females and males showed different sensitivities to factors affecting their ramet dynamics. The ramet recruitment, growth, and survival within male genets were significantly positively affected by the largest main ramet size, whereas females were not sensitive to the effect. This suggested that demographic patterns of ramets within male genets were more sensitive to assimilates translocated from the main ramets than those within female genets, and the role of clonal integration worked differently on ramet dynamics between sexes. Key words: clonal growth, module, physiological integration, sexual dimorphism, understory. Chez les plantes clonales, les ramettes connectees a un genet peuvent partager des ressources par une integration clonale, et l'integration clonale facilite souvent la croissance et la survie des jeunes ramettes. Cependant, chez les plantes dio'iques, on ne comprend pas bien si les genets males et femelles different dans leurs patrons d'integration affectant les processus demographiques. Pour etudier les differences entre sexes dans le processus demographique en relation avec l'integration clonale, les auteurs ont conduit un recensement a long terme chez l'arbuste dio'ique Lindera triloba (Sieb. Et Zucc.) Blume. Dans une foret surannee, ils ont selectionne 73 et 82 genets femelles et males respectivement, et ils ont suivi pendant six ans le recrutement, la croissance et la mortalite des ramettes de ces genets. On observe un recrutement plus important de ramettes males que de femelles, alors que la croissance des ramettes et les taux de survie ne different pas en moyenne entre les sexes. Les femelles et les males montrent des sensibilites differentes envers les facteurs affectant la dynamique de leurs ramettes. Le recrutement des ramettes, la croissance et la survie chez les genets males sont positivement et significativement affectes par la dimension de la ramette principale la plus grosse, alors que les femelles ne sont pas sensibles a cet effet. Ceci suggere que les patrons demographiques des ramettes chez les genets males sont plus sensibles aux assimilats provenant des ramettes principales que celles des genets femelles, et que le role de l'integration clonale agit differemment sur la dynamique selon les sexes. Mots-cles : croissance clonale, module, integration physiologique, dimorphisme sexuel, sous etage. [Traduit par la Redaction], Introduction Modular organisms show various levels of autonomy and integration among their modules (reviewed by de Kroon et al. 2005). In long-term ecological research, the ecological features of clonal plants [...]

Reduced pollen availability in a fragmented population may affect pollen immigration and diversity of pollen donors in the population. To test this prediction, tree locations, tree sizes, and nuclear microsatellite genotypes were determined for 182 offspring, their 8 mothers, and 194 males of a wind-pollinated, dioecious Salix arbutifolia Pallas population along a river isolated over 4 km from other populations. The effects of the distance between the mother and male trees and the size of the male trees on pollen dispersal as well as fractional paternity allocation for the offspring and the number of unsampled males were estimated simultaneously. Based on the estimated parameters of pollen dispersal, the availability of pollen from the males along the river was obtained for the individual mother trees. The pollen availability was not correlated with the proportion of offspring sired by immigrating pollen from unsampled males (8%-50%), but was positively correlated with the effective number of pollen donors in sampled males (1-8). The results suggest that the reduced pollen donor diversity owing to low pollen availability increases the fraction of full-sibs in offspring and subsequent reduction in genetic diversity, but that pollen immigration compensates the offspring for the reduced genetic diversity. Key words: fragmentation, microsatellite loci, paternity assignment, pollen-mediated gene flow, wind pollination. La disponibilite reduite du pollen dans une population fragmentee peut affecter l'immigration pollinique et la diversite des donneurs de pollen dans la population. Afin de verifier ce postulat, les auteurs ont determine la localisation, les dimensions et les genotypes par microsatellites nucleiques, chez 182 rejetons, leurs 8 meres et 194 males d'une population dioique du Salix arbutifolia Pallas, pollinisee par le vent et situee le long d'une riviere, separee par 4 km d'autres populations. Les auteurs ont estime simultanement les effets de la distance entre les arbres males et femelles, la dimension des arbres males sur la dispersion du pollen ainsi que l'allocation fractionnaire de la paternite pour les descendants avec le nombre de males non echantillonnes. Basee sur les parametres estimes de la dispersion du pollen, la disponibilite du pollen provenant des males le long de la riviere a ete obtenue pour les arbres femelles individuels. On ne trouve pas de correlation entre la disponibilite du pollen et la proportion des descendants generes par du pollen immigrant a partir de males non echantillonnes (8%-50%), mais on observe une correlation positive avec les nombres reels de donneurs de pollen pour les males echantillonnes (1-8). Les resultats suggerent qu'une reduction de la diversite des donneurs polliniques due a une faible disponibilite en pollen augmente la fraction plein-frere chez les descendants avec une reduction subsequente de la diversite genetique, mais que l'immigration du pollen compense les descendants pour la reduction de la diversite genetique. Mots-cles: fragmentation, lieu microsatellite, attribution de la paternite, flux genetique par le pollen, pollinisation par le vent. [Traduit par la Redaction], Introduction Habitat fragmentation owing to recent anthropogenic disturbance leads to reductions in plant population size and connectivity among habitats (Lienert 2004). The habitat fragmentation is likely to alter mating patterns [...]

The sexual dimorphism of reproductive investment (measured as dry mass of reproductive tissues) at stem and whole plant (i.e., genet) levels in a dioecious clonal shrub, Ilex leucoclada (Maxim.) Makino., was examined over 2 consecutive years. Five patches in which different genets had already been distinguished using molecular markers in a previous study were selected, and the stem length, numbers of flowers and fruits, and sex of each stem were recorded. Fresh inflorescences and fruits were randomly sampled to estimate the reproductive investment of each stem. The male plants invested more resources in flowering at both the stem and genet levels than female plants, but females invested more resources than males when fruit masses were considered in addition to flower masses. The degrees of sexual dimorphism in reproductive investment at the stem and genet levels were similar, for both flowering alone and flowering plus fruiting. However, the reproductive investment was more restricted to large stems in female genets than in males. Inter-year fluctuations in reproductive investment were greater for females than males at both levels. These results suggest that patterns of reproductive investment should be examined simultaneously at multiple modular levels to obtain a thorough understanding of gender- associated variations in clonal plants. Key words: clonal plant, dioecy, genet, ramet, reproductive investment, sexual dimorphism. Les auteurs ont examine, au cours de 2 annees, le dimorphisme sexuel et le degre d'allocation a la reproduction (mesuree sous forme de matiere seche du tissu reproducteur), a la tige et a l'ensemble de la plante (c.-a-d. genet) chez un arbuste clonal dioi'que, l'Ilex leucoclada (Maxim.) Makino. Ils ont selectionne cinq colonies dont differents genets avaient deja ete cibles a l'aide de marqueurs moleculaires dans une etude anterieure, et ils ont mesure la longueur des tiges, le nombre de fleurs et le sexe de chaque tige. Ils ont echantillonne au hasard les inflorescences et les fruits frais pour evaluer l'allocation a la reproduction chez chaque tige. Les plantes males investissent plus de ressources a la floraison, aux echelles de la tige aussi bien que du genet, que les plantes femelles, mais les plantes femelles investissent plus de ressources que les males lorsque l'on considere la masse des fruits en plus de celle des fleurs. Les degres du dimorphisme sexuel en terme d' allocation a la reproduction a l'echelle de la tige et du genet apparaissent similaires, a la fois pour la floraison prise individuellement et la floraison avec la fructification. Cependant, l'allocation a la reproduction demeure plutot restreinte aux grandes tiges chez les genets femelles que chez les males. Les fluctuations interannuelles de l'allocation a la reproduction s' averent plus importantes chez les femelles que chez les males. Ces resultats suggerent qu'on devrait examiner le patron d' allocation a la reproduction a divers degres modulaires simultanement, pour obtenir une connaissance approfondie des variations associees aux genres chez les plantes clonales. Mots-cles : plante clonale, diecie, genet, ramette, allocation a la reproduction, dimorphisme sexuel. [Traduit par la Redaction], Introduction In sexually dimorphic plants there are differences between the sexes in both morphological traits (Lloyd and Webb 1977) and life histories (Delph 1999), which arise from differences in their [...]

Plant size and light availability may affect male and (or) female reproductive success and their relative contribution (functional gender). To test this hypothesis, we identified parents of 184 seedlings in a local population within a metapopulation of a hermaphroditic, insect-pollinated tree species, Magnolia stellata (Siebold & Zucc.) Maxim., using 14 nuclear and 3 chloroplast microsatellite markers. Parent pairs of all the seedlings were determined, and both seed and pollen parents could be distinguished for 49.5% of the seedlings. We also measured the parents' plant size (diameter at breast height of the thickest ramet within each genet; [DBH.sub.t]) and the relative photosynthetic photon flux density rPPFD) they received. The proportion of seedlings that originated from selfing was 20.7%. The number of seedlings parental trees produced as seed parents (S) was positively affected by [DBH.sub.t] and rPPFD. [DBH.sub.t] (but not rPPFD) also positively affected the number of seedlings sired as pollen parents (P). The femaleness of the parental trees (S/(S + P)) was positively affected by [DBH.sub.t], probably because [DBH.sub.t] had a stronger effect on the trees' reproductive success as seed parents than on their success as pollen parents. These results suggest that plant size affects not only reproductive success (male and female), but also functional gender. Key words: inbreeding depression, entomophilous, geitonogamy, molecular markers, parentage analysis, protogynous, selfing rate. La dimension des plantes et la disponibilite de la lumiere peuvent affecter le succes reproductif male/ou femelle ainsi que leur contribution relative (genre fonctionnel). Afin de verifier cette hypothese, les auteurs ont identifie les parents de 184 plantules d'une population locale au sein d'une metapopulation d'une espece ligneuse hermaphrodite pollinisee par les insectes, le Magnolia stellata; a cette fin, ils ont utilise 14 marqueurs nucleiques et trois marqueurs chloroplastiques microsatellites. Ils ont determine la paire de parents de toutes les plantules, et ils ont pu distinguer les parents polliniques et seminaux chez 49,5 % de ces plantules. Ils ont egalement mesure la dimension des plants- parents (diametre a la hauteur de poitrine de la ramette la plus large au sein de chaque genet; [DHP.sub.t]) ainsi que la densite relative du flux de photons (rPPFD) qu'ils recoivent. La proportion des plantules provenant d'autofecondations est de 20,7 %. On observe un effet positif du nombre de plantules produites par les arbres-parents comme parents seminaux (S) du [DHP.sub.t] et du rPPFD. Le [DHP.sub.t] (mais pas le rPPFD) affecte aussi positivement le nombre de plantules issues de parents polliniques (P). Le [DHP.sub.t] affecte la feminite des arbres-parents (S/(S+P), probablement parce que le [DHP.sub.t] exerce un effet plus important sur le succes reproductif des arbres comme parent seminaux que polliniques. Ces resultats suggerent que la dimension de la plante influence non seulement le succes reproductif, mais aussi le genre fonctionnel. Mots-cles: depression d'autofecondation, entomophilie, geitonogamie, marqueurs moleculaires, analyse de parentage, protogyne, taux d' autofecondation. [Traduit par la Redaction], Introduction Sexually monomorphic plants act not only as seed (female) parents, but also as pollen (male) parents. In such plants, female and male functions do not necessarily contribute equally to [...]

We investigated the structure and dynamics of the multi-stemmed understory shrub Lindera triloba (Sieb. et Zucc.) Blume over 3 years in an old-growth coniferous forest, and quantitatively evaluated the factors affecting the ramet production, growth, and survival. Most genets sprouted continuously and exhibited multiple-stemmed structures with a few large and many small ramets. The skewed ramet-size distribution within genets resulted from the local crowding of neighboring trees, but not from the number of ramets within genets. This indicated that inter-plant competition is asymmetric (i.e., larger individuals outcompete one-sidedly smaller ones), but intra-plant competition (i.e., competition among ramets within genets) is symmetric (i.e., smaller ones also competitively affect larger ones). The local crowding of neighboring understory trees consistently negatively affected the ramet production, growth, and survival of L. triloba. Intra-genet crowding (i.e., crowding of ramets within genets) also negatively affected the ramet dynamics. On the other hand, the largest-ramet size within genets had positive relationships with the ramet dynamics, indicating that physiological integration within genets plays a role as supporting younger ramets. Based on our results, to fully understand genet persistence strategies in clonal shrub species, it is important to consider the effects of intra-genet crowding and modular integration, as well as plant-to-plant interaction. Key words: clonal growth, physiological integration, competition, size structure. Les auteurs ont examine la structure et la dynamique de l'espece arbustive de sous-bois a tiges multiples, le Lindera triloba (Sieb. et Zucc.) Blume, au cours de 3 annees dans une vieille foret de coniferes; ils ont evalue quantitativement les facteurs qui influencent la production des ramettes, leur croissance et leur survie. La plupart des genets bourgeonnent continuellement et montrent des structures a plusieurs tiges avec quelques grosses et plusieurs petites ramettes. La curtose observee dans la distribution de la dimension des ramettes, entre les genets, provient de l'entassement localise; des arbres voisins, mais non du nombre de ramettes au sein des genets. Ceci indique que la competition entre plants est asymetrique (i.e., les individus plus gros eliminent d'un cote les plus petits), mais que la competition a l'interieur du plant (i.e., competition entre les ramettes au sein des genets) est symetrique (i.e., les plus petits affectent egalement les plus gros par competition). L'attroupement local des arbres voisins du sous-bois affecte negativement de facon congrue la production de ramettes, la croissance et la survie du L. triloba. L'attroupement au sein du genet (i.e., attroupement des ramettes au sein des genets), affecte aussi negativement la dynamique des ramettes. D'un autre cote, la ramette la plus grosse dans les genets montre une relation positive avec la dynamique des ramettes, ce qui indique que l'integration physiologique au sein des genets joue un role comme support pour les jeunes ramettes. A partir de ces resultats, pour comprendre completement les strategies de persistance chez les especes arbustives clonales, il faut considerer les effets de l'attroupement au sein des genets et l'integration modulaire aussi bien que l'interaction plante-plante. Mots-cles: croissance clonale, integration physiologique, competition, structure dimensionnelle. [Traduit par la Redaction], Introduction Basal sprouting is one of the common growth forms of many shrub species that grow clonally on forest floors (Jenik 1994). Sprouting results from responses to recover the aboveground [...]

Abstract: We have examined the earliness, duration, and amplitude of flowering genets in a Magnolia stellata (Sieb. et Zucc.) Maxim. population in relation to their size, environmental factors (temperature and [...]