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Gnomoniopsis (Gnomoniaceae, Diaporthales) is a well-classified genus inhabiting leaves, branches and fruits of the hosts in three plant families, namely Fagaceae, Onagraceae and Rosaceae. In the present study, eighteen Gnomoniopsis isolates were obtained from diseased leaves of Fagaceae hosts collected from Fujian, Guangdong, Hainan, Henan, Jiangxi and Shaanxi provinces in China. Morphology from the cultures and phylogeny based on the 5.8S nuclear ribosomal DNA gene with the two flanking internally transcribed spacer (ITS) regions, the translation elongation factor 1-alpha (tef1) and the beta-tubulin (tub2) genes were employed to identify these isolates. As a result, seven species were revealed, viz. Gnomoniopsis&nbsp, castanopsidis, G.&nbsp, fagacearum, G. guangdongensis, G.&nbsp, hainanensis, G. rossmaniae and G. silvicola spp. nov, as well as a known species G. daii. In addition, G. daii was firstly reported on the host Quercus&nbsp, aliena.

The genus Quercus L. is one of the most abundant and important genera of woody plants in the Northern Hemisphere as well as in Turkey. In the current study which is the most comprehensive study dealing with Turkish oaks, sequence variations of three noncoding regions (trnT((UGU))-L-(UAA) IGS, trnL((UAA))intron, trnL((UAA))-F-(GAA) IGS) of chloroplast DNA (cpDNA) were used for phylogeographic and phylogenetic analysis on 319 individuals representing 23 taxa (17 species). The trnT((UGU))-L-(UAA) region was found to be the most variable and parsimony informative region. Twenty-eight cpDNA haplotypes were identified based on 34 substitutions and 22 indels. High number of haplotypes and h(T) > v(T) observed in populations of oaks in Turkey indicated that the Anatolian Peninsula might have been a refugium at Glacial Periods. Phylogeographic construction and molecular variance analysis revealed that Quercus cpDNA haplotypes were geographically structured. Although local haplotype sharing among species from same infrageneric clades was common, levels of hybridization differ between species pairs. Haplotype analysis revealed four infrageneric clades, namely Section Quercus, Section Cerris and two clades corresponding to Section Ilex, namely "Ilex" and "Coccifera." Furthermore, a Section Cerris haplotype was detected in the Aegean members of Q. ilex and Q. coccifera. Section Ponticae was placed in the Section Quercus cluster. In contrast to the phylogenetic reconstructions based on the nuclear DNA sequence data, Group Ilex seems to be polyphyletic based on plastome phylogeny. Chloroplast phylogeny of oaks reflects the traces of recent and ancient introgression events during diversification of species. In addition to this, incomplete linkage sorting may also explain this polymorphic assemblage. Therefore, further investigation is required to clarify the cpDNA phylogeny of oaks, especially for Section Ilex.

International audience; The systematics of Quercus faginea Lam. (s.l.) (Fagaceae) remains obscure, as it tends to crossbreed with other species and show signs of polymorphism. Four subspecies were identified and currently recognized in the Iberian Peninsula and Morocco. However, the literature to date does not allow the distinction between the taxa present in Algeria. To remedy the lack of required data, a morphological and taxonomic analysis of 13 tree populations has been carried out in the country. In the process, 20 leaves and 20 buds from 10 mature trees were collected at each population to produce a more detailed description of 23 particular morphological traits. MCA (multiple correspondence analysis) and AHC (ascendant hierarchical clustering) were used to analyze the data and to identify homogeneous groups. The results obtained show high intra and inter-population variability, with leaf size diminishing from east to west and from north to south of the country. Though the findings were remarkable, they alone could not be used to differentiate between populations under examination; the traits relating to blade shape and indumentum type on the leaf prove to be more useful. It is clear from this study that the Q. faginea Lam. group in Algeria is represented by two species: Quercus canariensis Willd. and Q. faginea Lam., the latter being represented by two taxa: subsp. faginea and subsp. broteroi.; La systématique de Quercus faginea Lam. (s.l.) (Fagaceae) reste encore indéfinie, d’autant plus qu’elle s’hybride avec d’autres espèces et qu’elle est polymorphe. Quatre sous-espèces ont été identifiées et présentement reconnues en péninsule Ibérique et au Maroc, or, les données disponibles ne permettent pas de trancher entre les taxons présents en Algérie. Pour remédier au manque de données nécessaires, une analyse morphologique et taxonomique de treize populations du complexe dans le pays a été effectuée. Dans chacune, 20 feuilles et 20 bourgeons sur 10 arbres matures ont été prélevés pour une description détaillée de 23 traits morphologiques. L’ACM (analyse des correspondances multiples) et la CAH (classification ascendante hiérarchique) ont été utilisées pour analyser les données et identifier des groupes homogènes. Une variabilité significative intra et inter-populationnelle est remarquable, avec une taille de feuilles qui tend à diminuer en allant de l’est vers l’ouest et du nord au sud du pays. Cette variabilité ne permet pas, à elle seule, de différentier entre les populations étudiées, en revanche, les traits liés à la forme du limbe et aux types du « tomentum » sur la feuille s’avèrent plus utiles. Cette étude confirme que le complexe Q. faginea Lam. est représenté en Algérie par deux espèces : Quercus canariensis Willd. et Q. faginea Lam., elle-même représentée par deux taxons, subsp. faginea et subsp. broteroi.

The montane subtropical broad-leaved humid forests of Meghalaya (Northeast India) are highly diverse and situated at the transition zone between the Eastern Himalayas and Indo-Burma biodiversity hotspots. In this study, we have used inventory data from seedlings to canopy level to assess the impact of both biotic and abiotic disturbances on structure, composition, and regeneration potential of the Fagaceae trees of these forests. Fagaceae trees are considered as the keystone species in these forests due to their regional dominance and their importance as a fuel wood source, and also because they form an important component of climax community in these forests. Unfortunately, these forests are highly degraded and fragmented due to anthropogenic disturbances. We have assessed, for the first time, the restoration potential (i.e., capacity to naturally regenerate and sustain desired forest structure) of Fagaceae species in the genera Lithocarpus Blume, Castanopsis (D. Don) Spach, and Quercus Linn. We also evaluated how biotic and abiotic factors, as well as anthropogenic disturbances, influence the restoration potential of these species in six fragmented forest patches located along an elevational gradient on south-facing slopes in the Khasi Hills, Meghalaya. Fagaceae was the most dominant family at all sites except one site (Laitkynsew), where it was co-dominant with Lauraceae. Fagaceae forests have shown high diversity and community assemblages. Fagaceae species had high levels of natural regeneration (i.e., seedlings and saplings) but low recruitment to large trees (diameter at breast height or DBH &ge, 10 cm) at all sites. The ability to sprout was higher in Fagaceae tree species than non-Fagaceae tree species. We have shown that human disturbance and structural diversity were positively related to regeneration of Fagaceae tree species due to high sprouting. However, with increasing human disturbance, recruitment of saplings and pole-sized trees to mature trees hampered the resulting proportion of mature Fagaceae tree species. This study provides a means for assessing regeneration and a basis for forest management strategies in degraded and fragmented forests of Meghalaya.

Forests are already and will continue to experience a rapid and extreme change in climatic conditions in the future. The distributions of forests are expected to shift northward and to higher altitudes based on the results of species distribution modelling (SDM). Although SDM is criticized for lack of biotic interactions and natural migration mechanisms, it is still an important tool for understanding the influence of climate change on forest distributions at a landscape scale. We hypothesize that based on extant forest cover, distribution of protected areas and understanding on seed dispersal mechanisms, the suitable range of forest tree species will decline, and certain species might be driven to extinction in the absence of suitable space for migrations in a rapidly changing climate. To assess this scenario, we modelled the current and future potential distribution of 18 Castanopsis species in Asia using MaxENT. Mild (RCP-4.5) and severe (RCP-8.5) climate change scenarios from 17 climate change models were assessed. Three groups of current Castanopsis distribution were identified and they responded differently under climate change. One-third of the species will experience potential range reductions while two-third will have potential range expansions. However, when we overlaid the results with forest cover and protected area coverage, range expansions are unlikely to happen due to fragmented forest cover and lack of efficient seed dispersal mechanisms. Natural species migrations and local adaptation are not likely to happen for Castanopsis and therefore immediate adaptive strategies should be considered in forest management. This situation was particularly severe in the marginal tropical zones across coastal South China and the Northern Indo-China region.

The Fagaceae family is currently widespread throughout tropical and temperate regions of South America and the Northern Hemisphere, especially East Asia, and has likely been so since the Eocene, according to fossil records. In China, Fagaceae fossils are rare in the lowest latitudes of South China. Here, we describe 12 species in 5 genera of Fagaceae (i.e. Berryophyllum, Castaneophyllum, Quercus, Castanopsis and Lithocarpus) based on leaf morphology and trichomes. These fossils are recovered from the Changchang Formation of Changchang Basin, Hainan Island, South China, indicating that Fagaceae has been distributed in these tropical low latitudes since the Eocene. Given that our fossils are closely related to the tropical and subtropical extant species, we speculate that Fagaceae lineages have likely diverged since the Eocene and that each extant lineage, such as Quercus sect. Cyclobalanopsis, became highly differentiated no later than middle Eocene. Based on the current living conditions of the extant species, we further speculate that the climate of Hainan Island was warm and wet during the middle Eocene, suitable for the growth and differentiation of the family.

Eocene Baltic amber forms the largest amber deposit worldwide; however, its source vegetation and climate are much debated. Representatives of the oak family (Fagaceae) were abundant in the Baltic amber source area based on numerous inclusions of staminate inflorescences or individual florets, previously assigned to Castanea and Quercus. However, the actual generic and infrageneric diversity of Fagaceae from Baltic amber remained unknown. Using flower characteristics and section-diagnostic in situ pollen of staminate inflorescences and detached floret inclusions, we describe 18 fossil-species of Fagaceae making this family by far the most diverse plant family preserved in Baltic amber. We substantiate the occurrence of the Castaneoideae, Quercoideae (Quercus sect. Cyclobalanopsis/Lobatae; Q. sect. Lobatae; Q. sect. Protobalanus), Trigonobalanoideae and the extinct genus Eotrigonobalanus. Among the 18 fossil-species, six are described as new: Q. aimeeana, Q. casparyi, Q. multipilosa, E. campanulata, E. conwentzii, E. longianthera; and one new combination is published: Q. brachyandra (≡ Castanea brachyandra). In addition, a lectotype is designated for the name Quercites meyerianus and neotypes are designated for the names Castanea inclusa and Quercus longistaminea (≡ C. longistaminea). Members of the Fagaceae probably inhabited azonal and zonal vegetation types of the amber source area, including bottomland flood-plains and stream banks (Q. sect. Lobatae), dry habitats (Q. sect. Lobatae, Q. sect. Protobalanus), peaty soils, riparian and swamp forests (Castanopsis, Eotrigonobalanus), as well as mixed mesophytic forests (castaneoids, Quercoideae, trigonobalanoids). Affinities to extant North American and E to SE Asian floras support the recent notion that late Eocene Baltic amber (38–34 Ma) was formed in a warm-temperate climate.

Castanea sativa is particularly exploited in the Mediterranean basin, for fruit and wood production. Several authors studied the possible effects of C. sativa compounds as interesting ingredients f...

Invasions by non-native pathogens represent a major threat to managed and natural ecosystems worldwide. Although necessary for adopting preventive strategies, the identification of invasive species before they are introduced is particularly difficult. Indeed, most pathogenic species that have become established in the last decades were first described only after they became invasive. To prevent further biological invasions, not only the early identification of potential new invasive plant pathogens is crucial, but also the assessment of their potential host range. In this study, we determined the pathogenicity and the saprotrophic ability of three Cryphonectria species towards three potential hosts in the family Fagaceae. For this, seedlings and dormant stems of European chestnut (Castanea sativa), pedunculate oak (Quercus robur) and European beech (Fagus sylvatica) were inoculated with different genotypes of C. parasitica (Asian species, invasive in Europe), C. naterciae (European species), and C. japonica (Asian species, not present in Europe). Lesion growth was measured and mortality assessed for four months. The highest damage was caused by C. parasitica on European chestnut, while C. japonica and C. naterciae induced significantly smaller lesions on this host species. All three Cryphonectria species did not grow saprophytically on F. sylvatica and Q. robur, but successfully colonized dormant stems of C. sativa. In the context of biological invasions, our study shows that the Asian C. japonica most likely represents a much less severe threat than C. parasitica for the tested European host species. Nonetheless, the ability of C. naterciae and C. japonica to saprotrophically colonize fresh chestnut wood may suggest that they could become established in chestnut forests and eventually infect weakened chestnut trees or other hosts not tested in this study.

In the present article, the establishment of the species Castanopsis: C. bulgarica Mantzouka, Ivanov, and Bozukov is proposed after the study of a new fagaceous fossil wood stem discovered in 2016 from a new Late Miocene to Early Pliocene plant fossiliferous locality east of Boboshevo town, south-west Bulgaria. A detailed palaeoxylotomical study of the fossil wood revealed characteristics of the ‘evergreen Quercus type’ (e.g. the gradual porosity of the vessels, the existence of two types of rays: uniseriate and multiseriate aggregate, the oval shape of the solitary vessels outline, the occurrence of tracheids) as well as heterocellular compound-aggregate rays, typical for Castanopsis. Similarities and differences of the anatomical characteristics/features of the studied specimen with the descriptions of the fossil representatives of Fagaceae (Quercoxylon, Lithocarpoxylon, and Castanopsis) along with its botanical affinities are discussed. A taxonomic list of the Bulgarian fossil fagaceous record of the same age and their nearest living relatives is provided. Emended xylotomical keys with the addition of Castanopsis have been created. Moreover, the presence of evergreen Castanopsis species with heterocellular rays of two distinct sizes in the fossil record of the ‘evergreen oak woods’ is supported.

Adaptation and acclimation of tree seedlings to different combinations of light and water conditions can determine the species-specific patterns of distribution along environmental gradients and the underlying physiological mechanisms are fundamental to the understanding of such patterns. Seedlings of two Cyclobalanopsis species naturally occurring in southwest China, with distinct distribution and regeneration characteristics, were grown under 100%, 50% and 4% sunlight conditions and traits related to shade and drought tolerance were studied. Particularly, we investigated whether leaf hydraulics, photosynthetic traits and their functional coordination play an important role in determining seedling environmental adaptation and acclimation of the two species. Seedlings of C. helferiana showed characteristics adapted to high irradiance while C. rex had traits adapted to partially shaded environments. Cyclobalanopsis helferiana had significantly higher maximum net photosynthetic rate (Amax), light compensation point and light saturation point than C. rex and the contrasts were particularly large when they were grown under full sunlight. Cyclobalanopsis helferiana showed the highest Amax when grown under 100% sunlight, while C. rex exhibited the highest Amax at 50% sunlight. Similarly, under full sunlight conditions C. helferiana showed significantly higher leaf hydraulic conductance (Kleaf) than C. rex, i.e., 13.37 vs. 7.09 mmol m&minus, 2 s&minus, 1 MPa&minus, 1 (p &lt, 0.01). The correlation between Kleaf and Amax followed a unified positive correlation across different light treatments of both species. Moreover, leaves of C. helferiana showed greater resistance to drought-induced hydraulic dysfunction and to desiccation than C. rex. The contrasts in functional traits between the two Cyclobalanopsis species are consistent with the hypothesis that there is a trade-off between shade tolerance and drought tolerance. Findings of the present study contribute to a deeper understanding of mechanisms of divergence between closely related (congeneric) species with respect to key ecophysiology associated with natural regeneration.

Castanopsis &times, kuchugouzhui Huang et Y. T. Chang was recorded in Flora Reipublicae Popularis Sinicae (FRPS) as a hybrid species on Yuelushan mountain, but it is treated as a hybrid between Castanopsis sclerophylla (Lindl.) Schott. and Castanopsis tibetana Hance in Flora of China. After a thorough investigation on Yuelushan mountain, we found a population of C. sclerophylla and one individual of C. &times, kuchugouzhui, but no living individual of C. tibetana. We collected C. &times, kuchugouzhui, and we sampled 42 individuals of C. sclerophylla from Yuelushan and Xiushui and 43 individuals of C. tibetana from Liangyeshan and Xiushui. We used chloroplast DNA sequences and 29 nuclear microsatellite markers to investigate if C. &times, kuchugouzhui is a natural hybrid between C. sclerophylla and C. tibetana. The chloroplast haplotype analysis showed that C. &times, kuchugouzhui shared haplotype H2 with C. sclerophylla on Yuelushan. The STRUCTURE analysis identified two distinct genetic pools that corresponded well to C. sclerophylla and C. tibetana, revealing the genetic admixture of C. &times, kuchugouzhui. Furthermore, the NewHybrids analysis suggested that C. &times, kuchugouzhui is an F2 hybrid between C. sclerophylla and C. tibetana. Our results confirm that C. &times, kuchugouzhui recorded in FRPS is a rare hybrid between C. sclerophylla and C. tibetana.

A new species, Quercus xuanlienensis Binh, Ngoc & Bon, is described from Xuan Lien Nature Reserve, Vietnam. The new species is morphologically similar to Q. edithiae Skan, in having 8–11 pairs of secondary veins, bowl-shaped cupules and ellipsoid to cylindrical-ellipsoid and basally convex nuts. It differs in having serrulate leaf margins only at apical 1/5–1/7, almost entire margins of bracts on cupule and much longer nuts. The species is also similar to Q. fleuryi Hickel & A. Camus in having leaves glabrous on both surfaces with only an apically serrulate margin but differs in having shorter petioles, cupules enclosing 1/5 of the nut and much longer nuts. In addition, Q. disciformis Chun & Tsiang. and Q. bella Chun & Tsiang., previously known from China, are newly recorded from Ba Vi National Park, Vietnam.

During surveys of Phytophthora diversity in natural and semi-natural Fagaceae forests in Austria, Italy and Portugal, four new cryptic species were isolated from rhizosphere soil samples. Multigene phylogeny based on nuclear ITS, beta-tubulin and HSP90 and mitochondrial cox1 and NADH1 gene sequences demonstrated that two species, P. tyrrhenica and P. vulcanica spp. nov., belong to phylogenetic Clade 7a, while the other two species, P. castanetorum and P. tubulina spp. nov., clustered together with P. quercina forming a new clade, named here as Clade 12. All four new species are homothallic and have low optimum and maximum temperatures for growth and very slow growth rates at their respective optimum temperature. They differed from each other and from related species by a unique combination of morphological characters, cardinal temperatures, and growth rates. Pathogenicity of all Phytophthora species to the root system of their respective host species was demonstrated in soil infestation trials. Portuguese Science and Technology Foundation (FCT); Portuguese national funds the European BiodivERsA project RESIPATH: Responses of European Forests and Society to Invasive Pathogens [BIODIVERSA/0002/2012]; Czech Ministry for Education, Youth and Sports; European Regional Development Fund [CZ.02.1.01/0.0/0.0/15_003/0000453]; Hungarian Scientific Research Fund (OTKA) [K101914]; European Union's Horizon research and innovation programme [635646]; POnTE (Pest Organisms Threatening Europe); Sardinian Regional Government info:eu-repo/semantics/publishedVersion

The anatomical structure of wood is complex and contains considerable information about its specific species, physical properties, growth environment, and other factors. While conventional wood anatomy has been established by systematizing the xylem anatomical features, which enables wood identification generally up to genus level, it is difficult to describe all the information comprehensively. This study apply two computer vision approaches to optical micrographs: the scale-invariant feature transform algorithm and connected-component labelling. They extract the shape and pore size information, respectively, statistically from the whole micrographs. Both approaches enable the efficient detection of specific features of 18 species from the family Fagaceae. Although the methods ignore the positional information, which is important for the conventional wood anatomy, the simple information on the shape or size of the elements is enough to describe the species-specificity of wood. In addition, according to the dendrograms calculated from the numerical distances of the features, the closeness of some taxonomic groups is inconsistent with the types of porosity, which is one of the typical classification systems for wood anatomy, but consistent with the evolution based on molecular phylogeny; for example, ring-porous group Cerris and radial-porous group Ilex are nested in the same cluster. We analyse which part of the wood structure gave the taxon-specific information, indicating that the latewood zone of group Cerris is similar to the whole zone of group Ilex. Computer vision approaches provide statistical information that uncovers new aspects of wood anatomy that have been overlooked by conventional visual inspection.

Restoring isolated patches of forest ecosystems in degraded landscapes could potentially lead to genetic loss and inbreeding. Therefore, this study determined the occurrence of genetic diversity among the tree speciesCastanopsis tribuloides,C. calathiformis, andLithocarpus polystachyusall of which were proven previously to be effective native tree species in the restoration of upland evergreen forests in northern Thailand when using the seed sample collection method. We tested our hypothesis as to whether the genetic diversity of a plant population that had been planted from the seeds of 4–6 adult trees would be lower and whether incidences of fixation index (Fis) would be higher among the second generation seedlings of these three Fagaceae species in isolated forest restoration trial plots. Microsatellite primers were selected from the entire genome sequence ofC.tribuloidesand the genetic sequences ofC. tribuloides,L. polystachyus, andC. calathiformiswere analyzed. Our results indicated a high degree of genetic diversity (He) inC. tribuloides(0.736) andC.calathiformis(0.481); however, a low level of genetic diversity was observed inL.polystachyus(0.281) within the restored forest. The fixation index for the second generation ofL.polystachyusandC.calathiformisin the restored forest showed evidence of inbreeding. These results imply the efficiency of the seed sample collection method and verify that it does not reduce the level of genetic diversity inC.tribuloidesandC. calathiformis. However, it may result in incidences of an inbreeding phenomena, suggesting the need to increase the number of adult trees used at the seed collection stage.

Wilf et al . (Research Articles, 7 June 2019, eaaw5139) claim that Castanopsis evolved in the Southern Hemisphere from where it spread to its modern distribution in Southeast Asia. However, extensive paleobotanical records of Antarctica and Australia lack evidence of any Fagaceae, and molecular patterns indicate shared biogeographic histories of Castanopsis , Castanea , Lithocarpus , and Quercus subgenus Cerris , making the southern route unlikely.

Twenty-five species of Quercus were collected in the state of Aguascalientes, 11 members of Quercus sect. Lobatae (red oak) and 14 members of Quercus sect. Quercus (white oak). Ten species were newly recorded. Quercus potosina is the commonest and most widely distributed species in the state. Eight species were found only in a single municipality, Calvillo or San José de Gracia. The species of Quercus are mainly distributed in oak and pine-oak forest in the western part of Aguascalientes. The municipalities with the greatest numbers of species are San José de Gracia, Calvillo and Jesús María, while Aguascalientes, Asientos, Cosío, El Llano, Rincón de Romos, Pabellón de Arteaga, and Tepezalá have the fewest representatives. San Francisco de los Romo is the only municipality without any Quercus records.

Geometric morphometric analyses (GMMs) of the leaf shape can distinguish two congeneric oak species Quercus dentata Thunberg and Quercus aliena Blume in sympatric areas. High genetic and morphological variation in different Quercus species hinder efforts to distinguish them. In China, Q. dentata and Q. aliena are generally sympatrically distributed in warm temperate forests, and share some leaf morphological characteristics. The aim of this study was to use the morphometric methods to discriminate these sympatric Chinese oaks preliminarily identified from molecular markers. Three hundred sixty-seven trees of seven sympatric Q. dentata and Q. aliena populations were genetically assigned to one of the two species or hybrids using Bayesian clustering analysis based on nSSR. This grouping served as a priori classification of the trees. Shapes of 1835 leaves from the 367 trees were analyzed in terms of 13 characters (landmarks) by GMMs. Correlations between environmental and leaf morphology parameters were studied using linear regression analyses. The two species were efficiently discriminated by the leaf morphology analyses (96.9 and 95.9% of sampled Q. aliena trees and Q. dentata trees were correctly identified), while putative hybrids between the two species were found to be morphologically intermediate. Moreover, we demonstrated that the leaf morphological variations of Q. aliena, Q. dentata, and their putative hybrids are correlated with environmental factors, possibly because the variation of leaf morphology is part of the response to different habitats and environmental disturbances. GMMs were able to correctly classify individuals from the two species preliminary identified as Q. dentata or Q. aliena by nSSR. The high degree of classification accuracy provided by this approach may be exploited to discriminate other problematic species and highlight its utility in plant ecology and evolution studies.

Fagaceae is one of the largest and economically important taxa within Fagales. Considering the incongruence among inferences from plastid and nuclear genes in the previous Fagaceae phylogeny studies, we assess the performance of plastid phylogenomics in this complex family. We sequenced and assembled four complete plastid genomes (Fagus engleriana, Quercus spinosa, Quercus aquifolioides, and Quercus glauca) using reference-guided assembly approach. All of the other 12 published plastid genomes in Fagaceae were retrieved for genomic analyses (including repeats, sequence divergence and codon usage) and phylogenetic inference. The genomic analyses reveal that plastid genomes in Fagaceae are conserved. Comparing the phylogenetic relationships of the key genera in Fagaceae inferred from different codon positions and gene function datasets, we found that the first two codon sites dataset recovered nearly all relationships and received high support. Thus, the result suggested that codon composition bias had great influence on Fagaceae phylogenetic inference. Our study not only provides basic understanding of Fagaceae plastid genomes, but also illuminates the effectiveness of plastid phylogenomics in resolving relationships of this intractable family.

A detailed survey was conducted in five national parks and game reserves of Azad Jammu and Kashmir, Pakistan to assess the biodiversity of family Fagaceae. Identification of the species was done using literary sources and comparison of samples with herbaria from Quaid-i-Azam University, Islamabad and Pakistan Museum of Natural History, Islamabad, Pakistan. A total of eight different species belonging to two genera were identified, including Quercus spp., Castanea sativa, Quercus glauca, Quercus baloot, Quercus incana, Quercus velutina, Quercus alba and Quercus dilatata. The greatest biodiversity was found in Banjosa Game Reserve (BGR) and Tolipir National Park (TNP), while Pir Chinasi National Park (PCNP), Pir Lasura National Park (PLNP) and Dhirkot National Reserve (DNR) had the least number of species.

HSV-1 is a neurotropic virus that replicates lytically during acute infection and establishes latency in peripheral neurons. Currently, the clinically approved compounds for the prevention of HSV-1 infection include acyclovir and penciclovir, however, long-term use of the drug is associated with serious side effects, and drug-resistant strains often appear. Therefore, it is important to find a safe and novel antiviral agent for HSV-1 infection. Quercus acuta Thunb. (Fagaceae) (QA) is widely distributed as an ornamental and dietary plant in Korea, Taiwan, China, and Japan. Thus far, the effects of QA extract and its active ingredients are known to have antioxidant, antibacterial, and anti-inflammatory activity, but studies of possible antiviral effects have not been reported. We studied the antiviral effects and molecular mechanism of QA after HSV-1 infection at the cellular level. We confirmed that QA suppresses ROS expression after HSV-1 infection and also suppresses inflammatory cytokine expression through inhibition of NF-кB activity. In addition, we found that QA increases the phosphorylation activity of IRF3 through induction of TBK1 activity during HSV-1 infection. QA exhibits an antiviral effect, and we confirmed through UPLC-DAD-mass spectrometer (MS)/MS analysis that it contains five main components: catechin, chlorogenic acid, fraxin, isoquercitrin, and taxifolin. Of these, isoquercitrin was confirmed to exhibit an antiviral effect on SK-N-SH cells through ICP27 inhibition. Overall, our results suggest that QA is a novel inhibitor with antiviral effects against HSV-1 infection and may be used specifically to prevent and treat of herpes simplex virus encephalitis infection.

Background Most genera of Fagaceae are thought to have originated in the temperate regions except for the genus Lithocarpus, the stone oaks. Lithocarpus is distributed in subtropical and tropical Asia, and its ancestral population is hypothesized to be distributed in tropical regions in Borneo and Indochina. Borneo and the nearby islands (the Greater Sunda Islands) were connected to the Malay Peninsula and Indochina prior to the Pliocene epoch and formed the former Sundaland continent. The Southeast Asian Lithocarpus, is thought to have dispersed between continental Asia and the present Sundaland. The drastic climate changes during the Pliocene and Pleistocene epochs which caused periodic sea-level changes is often used to explain the cause of its diversity. The aim of this study was to establish phylogenetic relationships by analyzing nuclear (nrDNA) and chloroplast (cpDNA) DNA in order to describe and analyze the origin, causes of diversification and historical biogeography of Lithocarpus. Results Phylogeny reconstructed through the multiple-species coalescent method with nrDNA and cpDNA revealed that the continental-Asian taxa were clustered at the basal lineages. The derived lineages of tropical Lithocarpus, with the inference of a subtropical ancestral state, imply a southward migration in the Early Miocene period with subsequent in situ diversification in the Greater Sunda Islands. The gradual decrease in temperature since the Middle Miocene period is proposed as a cause of the increase in the net diversification rate. Conclusions The historical ancestral origin of Lithocarpus has been suggested to be mainland Asia. Southward migration in the Early Miocene period with subsequent in situ diversification could explain the current diversity of stone oaks in Southeast Asia. This study also considered the multiple origins of stone oaks currently indigenous to the subtropical islands offshore and near mainland China. Our results provide phylogenetic evidence for a subtropical origin of Asian stone oaks and reveal the process of diversification and how it fits into the timeline of major geologic and climatic events rather than local, episodic, rate-shifting events. Electronic supplementary material The online version of this article (10.1186/s40529-018-0244-8) contains supplementary material, which is available to authorized users.

International audience

Oak represents a valuable natural resource across Northern Hemisphere ecosystems, attracting a large research community studying its genetics, ecology, conservation, and management. Here we introduce a draft genome assembly of valley oak (Quercus lobata) using Illumina sequencing of adult leaf tissue of a tree found in an accessible, well-studied, natural southern California population. Our assembly includes a nuclear genome and a complete chloroplast genome, along with annotation of encoded genes. The assembly contains 94,394 scaffolds, totaling 1.17 Gb with 18,512 scaffolds of length 2 kb or longer, with a total length of 1.15 Gb, and a N50 scaffold size of 278,077 kb. The k-mer histograms indicate an diploid genome size of ∼720–730 Mb, which is smaller than the total length due to high heterozygosity, estimated at 1.25%. A comparison with a recently published European oak (Q. robur) nuclear sequence indicates 93% similarity. The Q. lobata chloroplast genome has 99% identity with another North American oak, Q. rubra. Preliminary annotation yielded an estimate of 61,773 predicted protein-coding genes, of which 71% had similarity to known protein domains. We searched 956 Benchmarking Universal Single-Copy Orthologs, and found 863 complete orthologs, of which 450 were present in > 1 copy. We also examined an earlier version (v0.5) where duplicate haplotypes were removed to discover variants. These additional sources indicate that the predicted gene count in Version 1.0 is overestimated by 37–52%. Nonetheless, this first draft valley oak genome assembly represents a high-quality, well-annotated genome that provides a tool for forest restoration and management practices.

Lithocarpus vuquangensis Ngoc & Hung is described from Vu Quang National Park, North Central Vietnam. The morphological comparison and phylogenetic analysis based on rbcL, matK and ITS provided evidence that the new species was not assignable to any of the previously known taxa in Vietnam and its surrounding countries. The description, photographs, preliminary conservation status and DNA barcode sequences are also provided for the new species.

Quercus variabilis (Chinese cork oak) is an economically valuable oak as the source of industrial cork, which was widely distributed in eastern Asia. In this study, the complete mitochondrial genome of Q. variabilis was sequenced using the Illumina Hiseq and PacBio Sequel technique. The mitogenome is 412,886 bp in length and the GC content is 45.76%. The genome consists of 36 protein-coding genes, 3 ribosomal-RNA genes, and 21 transfer-RNA genes. Phylogenetic analysis based on protein-coding genes showed that Q. variabilis was close to the species in the Cucurbitaceae family.

Background and Aims The inverse relationship between atmospheric CO2 partial pressure (pCO2) and stomatal frequency in many species of plants has been widely used to estimate palaeoatmospheric CO2 (palaeo-CO2) levels; however, the results obtained have been quite variable. This study attempts to find a potential new proxy for palaeo-CO2 levels by analysing stomatal frequency in Quercus guyavifolia (Q. guajavifolia, Fagaceae), an extant dominant species of sclerophyllous forests in the Himalayas with abundant fossil relatives. Methods Stomatal frequency was analysed for extant samples of Q. guyavifolia collected from17 field sites at altitudes ranging between 2493 and 4497 m. Herbarium specimens collected between 1926 and 2011 were also examined. Correlations of pCO2-stomatal frequency were determined using samples from both sources, and these were then applied to Q. preguyavaefolia fossils in order to estimate palaeo-CO2 concentrations for two late-Pliocene floras in south-western China. Key Results In contrast to the negative correlations detected for most other species that have been studied, a positive correlation between pCO2 and stomatal frequency was determined in Q. guyavifolia sampled from both extant field collections and historical herbarium specimens. Palaeo-CO2 concentrations were estimated to be approx. 180-240 ppm in the late Pliocene, which is consistent with most other previous estimates. Conclusions A new positive relationship between pCO2 and stomatal frequency in Q. guyavifolia is presented, which can be applied to the fossils closely related to this species that are widely distributed in the late-Cenozoic strata in order to estimate palaeo-CO2 concentrations. The results show that it is valid to use a positive relationship to estimate palaeo-CO2 concentrations, and the study adds to the variety of stomatal density/index relationships that available for estimating pCO2. The physiological mechanisms underlying this positive response are unclear, however, and require further research

Background Plant secondary metabolites and phytochemicals that exhibit strong bioactivities have potential to be developed as safe and efficient natural antimicrobials against food contamination and addressing antimicrobial resistance caused by the overuse of chemical synthetic preservative. In this study, the chemical composition, antibacterial activities and related mechanism of the extracts of the valonia and the shell of Quercus variabilis Blume were studied to determine its potential as a safe and efficient natural antimicrobial. Methods The phenolic compositions of valonia and shell extracts were determined by folin-ciocalteau colourimetric method, sodium borohydride/chloranil-based assay and the aluminium chloride method and then further identified by the reverse-phase HPLC analysis. The antibacterial activities of valonia and shell extracts were evaluated by the agar disk diffusion method and agar dilution method. The related antibacterial mechanism was explored successively by the membrane of pathogens effect, phosphorous metabolism, whole-cell proteins and the microbial morphology under scanning electron microscopy. Results The n-butanol fraction and water fraction of valonia along with n-butanol fraction of the shell contains enrich phenolics including ellagic acid, theophylline, caffeic acid and tannin acid. The n-butanol fraction and ethanol crude extracts of valonia exhibited strong antibacterial activities against Salmonella paratyphi A (S. paratyphi A) and Staphylococcus aureus (S. aureus) with the DIZ values ranged from 10.89 ± 0.12 to 15.92 ± 0.44, which were greater than that of the Punica granatum (DIZ: 10.22 ± 0.18 and 10.30 ± 0.21). The MIC values of the n-butanol fraction and ethanol crude extracts of valonia against S. paratyphi A and S. aureus were 1.25 mg/ml and 0.625 mg/ml. The related antibacterial mechanism of n-butanol fraction and ethanol crude extracts of valonia may be attributed to their strong impact on membrane permeability and cellular metabolism. Those extracts exhibited strong antibacterial activity according to inhibit the synthesis of bacterial proteins and seriously change morphological structure of bacterial cells. Conclusions The n-butanol fraction and ethanol crude extracts of valonia had reasonably good antibacterial activities against S. paratyphi A and S. aureus. This study suggests possible application of valonia and shell as natural antimicrobials or preservatives for food and medical application.

Russula griseocarnosa, an ectomycorrhizal (ECM) fungus, is a species of precious wild edible mushrooms with very high market value in southern China. Its yield is affected by many factors including the tree species and environmental conditions such as soil microbiome, humidity. How the microbiome promotes the ECM fungus symbiosis with Fagaceae plants and sporocarp-producing has never been studied. In this study, we collected rhizosphere samples from Fujian province, the microbiota in the root and mycorrhizal rhizosphere were identified by Illumina MiSeq high-throughput sequencing. First, we compared three types of fungal communities: root tips infected with ECM Russula (type 1), tips with Russula sporocarp (type 2) and tips without ECM (type 3). Our results showed that the fungal richness was negatively correlated with Russula. Russula, Tomentella and Lactarius were common in Fagaceae ECM roots. As to the mycorrhizal interactions, Boletus may be considered as an indicator species for sporocarp-producing Russula, and Acremonium, Cladophialophora were associated with Russula symbiosis. Second, we analyzed the fungal and bacterial communities in rhizosphere soils from the corresponding to previously three types (type 1, 2, 3). Dacryobolus and Acidocella may be considered as an indicator species for sporocarp-producing Russula. Fungi Tomentella, Saitozyma, Elaphomyces and bacteria Acidicaldus, Bryobacter, Sorangium and Acidobacterium occurred more frequently in the ECM Russula rhizosphere. Furthermore, the indicators Elaphomyces, Tomentella, Sorangium had a positive correlation with Russula symbiosis by network analyses. Overall, our results suggest a relationship between micro-community and ECM Russula formation and Russula sporocarp, which may provide new strategies for improving Russula symbiosis rate and sporocarp production.

European beech (Fagus sylvatica L.) is a deciduous tree, widely distributed in Europe and largely appreciated for its wood and nutritive nuts. Beech leaf also enjoys food use as salad, but an understanding of its nutraceutical value is still far from being achieved. Indeed, and also taking into account beech leaf as a consistent biomass residue available beechwood production and use, it needs to be explored as a valuable renewable specialized source of bioactive molecules. In this context, an untargeted ultra-high-performance liquid chromatography hyphenated with high resolution mass spectrometry (UHPLC-HRMS) approach was favorably applied to a beech leaf alcoholic extract, which also was evaluated for its antiradical capability (by means of assays based on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and [2,2’-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid)] (ABTS) radical cation) and its ferric ion reducing power. Redox mitochondrial activity towards Caco-2 cells paved the way to explore the extract’s capability to inhibit intracellular Reactive Oxygen Species (ROS) using 2’,7’dichlorofluorescin diacetate (DCFH-DA) assay. Hydroxycinnamoyl derivatives, mainly belonging to the chlorogenic acid class, and flavonoids were the main constituents. Uncommon flavanone C-glycosides were also found, together with a plentiful flavonol diversity. Cell-free and cell-based assays highlight its dose-dependent antioxidant efficacy, providing a foundation for further investigation of beech leaf constituents and its valorization and use as a reservoir of bioactive natural products with potential nutraceutical applications.

The American chestnut (Castanea dentata [Marsh.] Borkh.; Fagaceae) was an historically important hardwood species in eastern deciduous forests of the United States and Canada prior to being nearly eradicated by chestnut blight (Cryphonectria parasitica (Murr.) Barr). Several remnant populations have been identified persisting across fragmented parts of the historical range. The identification and characterization of remnant C. dentata populations is important for breeding and conservation efforts, as they may represent potential genetic sources of local adaptation or blight resistance, but much of the historical range remains unsurveyed. Here, I report the locations, blight infection status, and reproductive status of remnant American chestnut in upland forested areas of western New York, finding several reproductive/potentially reproductive trees.

El roble colombiano (Quercus humboldtii) es una especie endémica, dominante y vulnerable de los bosques altoandinos. Su madera y fruto se han utilizado tradicionalmente en pequeña escala por las poblaciones rurales. Una mayor sincronía del proceso de germinación podría facilitar la producción de plántulas para su uso en los programas de conservación. En vivero, se evaluó la emergencia mediante la inmersión de semillas en cuatro soluciones de ácido giberélico (GA3) por 24 horas (0, 150, 300 y 600 mg L-1), a 4 °C. Se adoptó un diseño completamente al azar con cuatro repeticiones de 25 semillas. El tiempo medio de emergencia tuvo una media de 32 días; sin diferencias estadísticamente significativas entre las diferentes dosis. No hubo efecto del GA3 para la emergencia de plántulas hasta 300 mg L-1 (media= 92 %); sin embargo, fue desfavorable con 600 mg L-1 (20 %). Las semillas frescas de roble andino poseen un alto contenido de humedad (38 %). Lo anterior revela un probable comportamiento recalcitrante. Este estudio confirma, como en la mayoría de los encinos blancos del trópico, la ausencia de latencia y la alta viabilidad de sus semillas. El uso del GA3 no es un tratamiento pregerminativo útil para acelerar y uniformizar la emergencia de plántulas de Q. humboldtii.

Pre-dispersal seed removal of fleshy fruits and Quercus coccifera (Fagaceae) acorns in a recently burned Mediterranean habitat. The seed fate in early successional habitats can determine plant composition and regeneration capacity after disturbance. Pre-dispersal seed removal has been poorly studied in Mediterranean habitats, especially in burned and logged habitats. We assessed it for two years in pine forests with experiments excluding vertebrates from fleshy fruits (infructescences of Smilax aspera and Rubia peregrina) and acorns (branches of Quercus coccifera). We compared one unburned and one burned area (control). Acorn removal was nil in the burned area while in the unburned habitat seed removal occurred from the beginning of the experiments. It is suggested that the greater vegetation cover in the unburned area shelter rodents from predators and increased their activity. In contrast, reduced cover in the burned area and the occurrence of gnawed acorns on the ground suggest acorn removal by rodents mainly in the post-dispersive stage. Smilax aspera seed removal was slower, and total loss of fruits due to senescence higher, in the burned area. Seed removal appears to be conditioned by interannual variations related to the activity and density of granivores and frugivores, the availability of fleshy fruits, and the maturation of fruits. In post-fire managed areas the role of granivores and frugivores in the regeneration process should be taken into account. La depredación pre-dispersiva de semillas se refiere al ‘ataque’ o la muerte que puede experimentar una semilla en la planta madre o en el suelo junto a ella, antes de ser dispersada. Se evaluó la remoción pre-dispersiva de semillas por parte de vertebrados en tres especies de plantas, dos con frutos carnosos (Smilax aspera y Rubia peregrina) y otra de frutos no carnosos (Quercus coccifera). El estudio se realizó durante dos años en bosques mediterráneos de Cataluña al noreste de la Península Ibérica. Se comparó pinar quemado y sometido a gestión forestal “vs” pinar no quemado (control), mediante la evaluación de ramas con frutos cubiertos con malla metálica (experimentos de exclusión) para impedir el acceso de depredadores y ramas sin protección. La remoción de semillas de Q. cocciferapor parte de vertebrados fue nula en el área quemada durante los dos años del muestreo mientras que en el área no quemada la remoción ocurrió desde el inicio de los experimentos. Se sugiere que la mayor cobertura vegetal en el área no quemada favorece una mayor actividad de roedores gracias a la protección que ésta proporciona ante eventuales depredadores. Por otro lado, en el área quemada, la escasa cobertura vegetal y la presencia de bellotas roídas en el suelo son indicadores de remoción de bellotas por roedores en la etapa post-dispersiva. En el caso de Smilax aspera, la remoción de semillas fue más lenta, y la pérdida total de frutos por senescencia mayor, en el área quemada que en la no quemada. La incidencia de los animales sobre especies de frutos carnosos parece estar condicionada por variaciones interanuales relacionadas con la actividad y presencia de granívoros y frugívoros, la disponibilidad de frutos carnosos y la maduración de las diásporas. En hábitats quemados posteriormente gestionados se recomienda considerar la función de la fauna granívora y frugívora en el proceso de regeneración de estos ambientes doblemente perturbados.

In 30 Fagaceae individuals from the Castanea, Fagus and Quercus genera, the internal transcribed spacer region (ITS) of the ribosomal DNA (rDNA) was amplified and digested with four restriction enzymes (HaeIII, HpaII, Sau96I, and TaqI), producing ITS PCR-RFLP markers. This technique allowed the discrimination of the Fagaceae species according to genus, infrageneric group and ecological area. This study constitutes the first application of the alternative co-dominant marker system ITS PCR-RFLP in Fagaceae species and proved to be highly suitable for taxonomic and ecological discrimination, constituting a useful molecular tool for taxonomists and forestry researchers., The internal transcribed spacer (ITS) of ribosomal DNA has been used to confirm taxonomic classifications and define phylogenies in several plant species following sequencing or polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) techniques. In this study, co-dominant ITS PCR–RFLP molecular markers were produced in 30 Fagaceae individuals belonging to the Castanea, Fagus and Quercus genera in order to assess the potential of this technique for taxonomic discrimination and determination of phylogenies. The complete ITS region (ITS1-5.8S rRNA-ITS2) was amplified in most of the Fagaceae individuals as a single fragment of ∼700 bp. The ITS amplified products were digested with nine restriction enzymes, but only four (HaeIII, HpaII, TaqI and Sau96I) produced polymorphic/discriminative patterns. The total expected heterozygosity (HE) was 20.31 % and the gene diversity (I), 32.97 %. The ITS polymorphism was higher within the Quercus genus (85.3 %). The ITS PCR–RFLP markers clustered the Fagaceae species according to genus or infrageneric group (in the case of Quercus sp. individuals). Five oaks did not cluster in line with the adopted infrageneric classification, but three of these were grouped according to their actual ecological distributions. The ITS PCR–RFLP markers indicated their potential for phylogenetic studies since all Fagaceae individuals were discriminated according to genus, and most of the oaks were clustered according to infrageneric group or ecological area.

UNLABELLED • PREMISE OF THE STUDY The early Cenozoic was a key period of evolutionary radiation in Fagaceae. The common notion is that species thriving in the modern summer-dry climate of California originated in climates with ample summer rain during the Paleogene.• METHODS We investigated in situ and dispersed pollen of Fagaceae from the uppermost Eocene Florissant fossil beds, Colorado, United States, using a combined light and scanning electron microscopy approach.• KEY RESULTS Pollen types of Castaneoideae with affinities to modern Castanea, Lithocarpus, and Castanopsis were recognized. Pollen of the extinct genus Fagopsis represents a derived type of Castaneoideae pollen. Infrageneric groups of Quercus were well represented, including pollen of Group Protobalanus. The taxonomic diversity of Fagaceae and of the total plant assemblage indicates a mosaic of microclimates, that range from pronounced to weakly seasonal climates and depend on slope aspect and elevation. Continental climatic conditions may have triggered the evolution of sclerophyllous leaves and adaptive radiation in Quercus and other taxa thriving today under distinctly summer-dry and winter-dry climates.• CONCLUSIONS Vegetation types similar to modern vegetation belts of the Coastal Ranges (chaparral, nemoral conifer forest) were established in the Front Range in the late Eocene. Coeval plant assemblages from the Coastal Ranges of California indicate distinctly subtropical, moist climates. Hence, characteristic elements found today in the summer-dry and winter-dry climates of Pacific North America (Quercus Group Protobalanus, Notholithocarpus) may opportunistically have dispersed into their modern ranges later in the Cenozoic. This scenario is in contrast to the evolution and migration patterns of their western Eurasian Mediterranean counterparts (Quercus Group Ilex).

Background Many northern-hemisphere forests are dominated by oaks. These species extend over diverse environmental conditions and are thus interesting models for studies of plant adaptation and speciation. The genomic toolbox is an important asset for exploring the functional variation associated with natural selection. Results The assembly of previously available and newly developed long and short sequence reads for two sympatric oak species, Quercus robur and Quercus petraea, generated a comprehensive catalog of transcripts for oak. The functional annotation of 91 k contigs demonstrated the presence of a large proportion of plant genes in this unigene set. Comparisons with SwissProt accessions and five plant gene models revealed orthologous relationships, making it possible to decipher the evolution of the oak genome. In particular, it was possible to align 9.5 thousand oak coding sequences with the equivalent sequences on peach chromosomes. Finally, RNA-seq data shed new light on the gene networks underlying vegetative bud dormancy release, a key stage in development allowing plants to adapt their phenology to the environment. Conclusion In addition to providing a vast array of expressed genes, this study generated essential information about oak genome evolution and the regulation of genes associated with vegetative bud phenology, an important adaptive traits in trees. This resource contributes to the annotation of the oak genome sequence and will provide support for forward genetics approaches aiming to link genotypes with adaptive phenotypes. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1331-9) contains supplementary material, which is available to authorized users.

Macro-morphological leaf traits and genetic assignments were combined to study the differentiation and hybridization of three sympatric and inter-fertile white oak species (Quercus frainetto, Q. petraea, and Q. pubescens). The sampling was performed in a single forest stand of central Italy (Mount Vairano) in which the cover percentages of each of these three oak species were almost equal. The individuals classified as pure species and the hybrid individuals were divided into two subsets (A and B) which were subsequently statistically analysed. The results regarding the subset of pure individuals showed a clear separation between the three species on the basis of differences observed in the following leaf traits: basal leaf shape, petiole ratio, petiole length, number of intercalary veins, pubescence of the petiole, leaf area, number of lobes, lamina length, and percentage of venation. Regarding the subset of hybrid individuals, as expected, a wider pattern of leaf traits compared to that exhibited by the pure individuals was observed. The leaf traits of the pure species that had provided the greater genetic contribution in the hybridization process were easily identifiable. Quercus pubescens and its hybrids exhibited a higher degree of leaf traits variability when compared with those observed for Q. petraea and Q. frainetto.

Background Genetic markers and linkage mapping are basic prerequisites for comparative genetic analyses, QTL detection and map-based cloning. A large number of mapping populations have been developed for oak, but few gene-based markers are available for constructing integrated genetic linkage maps and comparing gene order and QTL location across related species. Results We developed a set of 573 expressed sequence tag-derived simple sequence repeats (EST-SSRs) and located 397 markers (EST-SSRs and genomic SSRs) on the 12 oak chromosomes (2n = 2x = 24) on the basis of Mendelian segregation patterns in 5 full-sib mapping pedigrees of two species: Quercus robur (pedunculate oak) and Quercus petraea (sessile oak). Consensus maps for the two species were constructed and aligned. They showed a high degree of macrosynteny between these two sympatric European oaks. We assessed the transferability of EST-SSRs to other Fagaceae genera and a subset of these markers was mapped in Castanea sativa, the European chestnut. Reasonably high levels of macrosynteny were observed between oak and chestnut. We also obtained diversity statistics for a subset of EST-SSRs, to support further population genetic analyses with gene-based markers. Finally, based on the orthologous relationships between the oak, Arabidopsis, grape, poplar, Medicago, and soybean genomes and the paralogous relationships between the 12 oak chromosomes, we propose an evolutionary scenario of the 12 oak chromosomes from the eudicot ancestral karyotype. Conclusions This study provides map locations for a large set of EST-SSRs in two oak species of recognized biological importance in natural ecosystems. This first step toward the construction of a gene-based linkage map will facilitate the assignment of future genome scaffolds to pseudo-chromosomes. This study also provides an indication of the potential utility of new gene-based markers for population genetics and comparative mapping within and beyond the Fagaceae.

Premise of the study: The American Cross Timbers forest ecosystem runs from southeastern Kansas to Central Texas and is primarily composed of post oak (Quercus stellata). This old-growth forest currently occupies only about 2% of its ancestral range. To facilitate genetic research on this species, we developed microsatellite primers specific to post oak from reduced genomic libraries. Methods and Results: Two Q. stellata individuals, sampled from the northern and southern range of the post oak forest, were subject to genomic reduction and 454 pyrosequencing. Bioinformatic analysis identified putative microsatellites from which 12 polymorphic primer sets were screened on three populations. The number of alleles observed ranged from five to 20 across all populations, while observed and expected heterozygosity values ranged from 0.05 to 0.833 and 0.236 to 0.893, respectively, within individual populations. Conclusions: We report the development of microsatellite markers, specific to post oak, to aid the study of genetic diversity and population structure of extant forest remnants.

A species of the tribe Synergini (Hymenoptera: Cynipidae) was reared from a gall collected in China on Castanea mollissima Blume and Castanea seguinii Dode. The morphological features of this gall wasp indicate that it is an undescribed species belonging to the genus Synergus and is herein described as a new species, Synergus castaneus Pujade-Villar, Bernardo et Viggiani sp. nov. (Hymenoptera Cynipidae: Synergini). This is the first known instance of a species of Synergus emerging from Castanea galls (Fagaceae). Data on the diagnosis, distribution, and biology of the new species are given. Morphological features of this species are discussed and illustrated. No other known gall-inducing species emerged from the collected galls, whereas tens of specimens of parasitoids and adults of the inquiline micromoth Andrioplecta pulverula Meyrick (Lepidoptera: Tortricidae) did. 28S-D2 and COI sequences confirmed that S. castaneus is a distinct species belonging to the genus Synergus.

International audience; A summary of 35 keynote, invited and volunteer papers delivered at a recent international conference is provided along with web links to PDFs of those presentations. Major conference themes targeted Genomic Tool Development for the Fagaceae and Application of Genomic Resources. The meeting provided a venue for reviewing the rapidly expanding knowledge base on Fagaceae genomics and for developing collaborations between scientists from Europe and North America.

International audience; An overview of recent achievements and development of genomic resources in the Fagaceae is provided, with major emphasis on the genera Castanea and Quercus. The Fagaceae is a large plant family comprising more than 900 species belonging to 8-10 genera. Using a wide range of molecular markers, population genetics and gene diversity surveys were the focus of many studies during the past 20 years. This work set the stage for investigations in genomics beginning in the early 1990s and facilitated the application of genetic and quantitative trait loci mapping approaches. Transferability of markers across species and comparative mapping have indicated tight macrosynteny between Quercus and Castanea. Omic technologies were more recently developed and the corresponding resources are accessible via electronic and physical repositories (expressed sequence tag sequences, single-nucleotide polymorphisms, candidate genes, cDNA clones, bacterial artificial chromosome (BAC) libraries) that have been installed in North America and Europe. BAC libraries and physical maps were also constructed in Castanea and Quercus and provide the necessary resources for full nuclear genome sequencing projects that are currently under way in Castanea mollissima (Chinese chestnut) and Quercus robur (pedunculate oak).

To test whether stomatal density measurements on oak leaf remains are reliable tools for assessing palaeoatmospheric carbon dioxide concentration [CO2], under changing Late Miocene palaeoenvironmental conditions, young seedings of oak (Quercus petraea, Liebl.) were grown at elevated vs. ambient atmospheric [CO2] and at high humidity combined with an increased air temperature. The leaf anatomy of the young oaks was compared with that of fossil leaves of the same species. In the experiments, stomatal density and stomatal index were significantly decreased at elevated [CO2] in comparison to ambient [CO2]. Elevated [CO2] induced leaf cell expansion and reduced the intercellular air space by 35%. Leaf cell size or length were also stimulated at high air humidity and temperature. Regardless of a temperate or subtropical palaeoclimate, leaf cell size in fossil oak was not enhanced, since neither epidermal cell density nor length of the stomatal apparatus changed. The absence of these effects may be attributed to the phenological response of trees to climatic changes that balanced temporal changes in environmental variables to maintain leaf growth under optimal and stable conditions. Quercus petraea, which evolved under recurring depletions in the palaeoatmospheric [CO2], may possess sufficient phenotypic plasticity to alter stomatal frequency in hypostomatous leaves allowing high maximum stomatal conductance and high assimilation rates during these phases of low [CO2]. (C) 1998 Annals of Botany Company.

International audience

A detailed karyotype analyses of the five species of Quercus L. (Q. coccifera L., Q. ilex L., Q. aucheri Jaub. and Spach, Q. cerris L. and Q. ithaburensis Decne subsp. macrolepsis (Kotschy) Hedge and Yalt.) belonging to Ilex and Cerris section were examined. The somatic chromosome number of all studied taxa 2n?=?24 was found. The karyotypes of investigated species showed the great similarity with the chromosome length and the position of centromere. Chromosome number and detailed karyotype of these species were first time counted from Turkey. © 2011 Taylor and Francis Group, LLC.