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Tanoak (Notholithocarpus densiflorus) is an evergreen tree in the Fagaceae family found in California and southern Oregon. Historically, tanoak acorns were an important food source for Native American tribes, and the bark was used extensively in the leather tanning process. Long considered a disjunct relictual element of the Asian stone oaks (Lithocarpus spp.), phylogenetic analysis has determined that the tanoak is an example of convergent evolution. Tanoaks are deeply divergent from oaks (Quercus) of the Pacific Northwest and comprise a new genus with a single species. These trees are highly susceptible to sudden oak death (SOD), a plant pathogen (Phytophthora ramorum) that has caused widespread deaths of tanoaks. In this study, we set out to assemble the genome and perform comparative studies among a number of individuals that demonstrated varying levels of susceptibility to SOD. First, we sequenced and de novo assembled a draft reference genome of N. densiflorus using cobarcoded library processing methods and an MGI DNBSEQ-G400 sequencer. To increase the contiguity of the final assembly, we also sequenced Oxford Nanopore long reads to 30× coverage. To our knowledge, the draft genome reported here is one of the more contiguous and complete genomes of a tree species published to date, with a contig N50 of ∼1.2 Mb, a scaffold N50 of ∼2.1 Mb, and a complete gene score of 95.5% through BUSCO analysis. In addition, we sequenced 11 genetically distinct individuals and mapped these onto the draft reference genome, enabling the discovery of almost 25 million single nucleotide polymorphisms and ∼4.4 million small insertions and deletions. Finally, using cobarcoded data, we were able to generate a complete haplotype coverage of all 11 genomes.

The tussock moth, Orgyia trigotephras Boisduval (Lepidoptera: Erebidae), is one of the main emerging pests of kermes oak, Quercus coccifera L. (Fagaceae), in the Mediterranean area, where it can cause the defoliation of several hectares of forests during its population outbreaks. Despite this, no specific sampling procedures to properly estimate the population density of this pest have been developed yet. The aims of this research were to develop and compare enumerative and binomial sequential sampling plans to estimate the population density of O. trigotephras in forest environments. Data were collected in four forest stands dominated by Q. coccifera in Tunisia for 7 years (from 2013 to 2019) to take into consideration the potential spatio‐temporal variability in pest density. Plant community composition was determined at the beginning of the experimental trials, and enumerative and binomial sampling plans were developed at precision levels of 0.15 and 0.25. Over the entire sampling period, the average O. trigotephras egg batch density differed significantly among sites. Sample sizes of enumerative sampling plans were approximately 39 and 109 trees to estimate an average density of 0.50 O. trigotephras egg batches per tree at the precision levels of 0.25 and 0.15, respectively. Instead, binomial sequential sampling plans required smaller sampling sizes than the enumerative sampling plan. Our findings represent the baseline to develop a program for monitoring O. trigotephras at a large spatial scale. [ABSTRACT FROM AUTHOR]

Quercus rehderiana Hand.-Mazz. belongs to Quercus sect. Heteroallenes' of the Fagaceae family. It is widely distributed in forests with rocky and non-rocky desertification in Guizhou Province of Southwest China. However, our knowledge of the adaptation strategies of Quercus in forests with rocky desertification is surprisingly lacking. In this study, 16 leaf traits (morphological, anatomical, and chemical) of Quercus rehderiana were investigated in 15 individuals in five 20 × 20 m quadrants of forests with rocky and non-rocky desertification. The aim was to analyze their strategies of adaptation to arid and poor-soil environments in forests with rocky desertification. The results showed that Quercus rehderiana leaves in forests with rocky desertification had a greater leaf thickness, specific leaf area, abaxial epidermis thickness, and sponge mesophyll thickness but a lower leaf area than in forests with non-rocky desertification. Quercus rehderiana leaves in forests with rocky desertification had higher calcium and magnesium concentrations and a higher N:P ratio but lower potassium and phosphorus concentrations than in forests with non-rocky desertification. The results of principal component analysis showed that forests with rocky desertification tended to show resource-conserving strategies with thicker leaf tissue and a lower nutrient concentration, while forests with non-rocky desertification tended to show resource acquisition strategies with a greater leaf area and potassium concentration. In resource-poor environments, species that adopt conservative resource strategies are more likely to survive; therefore, we forecasted that more conservative, slow-growing Quercus rehderiana will be more stable over time. [ABSTRACT FROM AUTHOR]

The effect of the 20th-century functional extinction of the American Chestnut (Fagaceae: Castanea dentata (Marshall) Borkh) on associated herbivorous insects is unknown. These insects include leafminers that spend at least part of their larval phase feeding between the epidermises of leaves. We surveyed leafminers on C. dentata , nonnative Castanea spp. and hybrids on Long Island, NY. We found 10 leafminer species feeding on Castanea spp. A first New York State record was documented for Stigmella castaneaefoliella (Chambers) (Lepidoptera: Nepticulidae). New host records are established for 6 lepidopterans, including a new host genus for Phyllonorycter basistrigella (Clemens) (Lepidoptera: Gracillariidae). We found no significant differences in the mean intensity of S. castaneaefoliella leaf mines on native and nonnative Castanea spp.; however, our sample size was small. Thus, we guardedly conclude that nonnative Castanea spp. can serve as refugia for C. dentata leafminers native to North America while acknowledging that the extent to which nonnative species are utilized requires further investigation. [ABSTRACT FROM AUTHOR]

A key question in insect community ecology is whether parasitoid assemblages are structured by the food plants of their herbivore hosts. Tritrophic communities centred on oak‐feeding cynipid gallwasps are one of the best‐studied tritrophic insect communities. Previous work suggests that host plant identity is a much stronger predictor of oak–cynipid interactions than of cynipid–parasitoid interactions. However, these relationships have not been formally quantified. We reason that the potential for ‘bottom‐up’ effects should increase with host plant phylogenetic diversity. We, therefore, generated quantified interaction network data for previously unstudied tritrophic cynipid communities in Sichuan, China, where, in addition to Quercus, cynipid host plants include Castanea, Castanopsis and Lithocarpus. We characterise these communities taxonomically and compare the extent to which host plant taxonomy predicts plant–herbivore and plant–parasitoid associations. We sampled 42,620 cynipid galls of 176 morphotypes from 23 host plant species, yielding over 4500 specimens of 64 parasitoid morphospecies. Many parasitoids were identifiable to chalcidoid taxa present in other Holarctic oak cynipid communities, with the addition of Cynipencyrtus (Cynipencyrtidae). As elsewhere, Sichuan parasitoid assemblages were dominated by generalists. Gallwasp–plant interaction networks were significantly more modular than parasitoid–plant association networks. Gallwasps were significantly more specialised to host plants (i.e. had higher mean d' values) than parasitoids. Parasitoid assemblages nevertheless showed significant plant‐associated beta diversity, with a dominant turnover component. We summarise parallels between our study and other Fagaceae‐associated cynipid communities and discuss our findings in light of the processes thought to structure tritrophic interactions centred on endophytic insect herbivores. [ABSTRACT FROM AUTHOR]

AbstractCastanopsis orthacantha Franch. 1899 is one representative tree species distributed in the evergreen broad-leaved forests of southwestern China. This species is an important source of timber for manufacturing furniture, floors, and paper. It also plays a significant role in maintaining ecological balance and stability. To help with the genetic diversity assessment of C. orthacantha, we sequenced and assembled the first complete chloroplast genome. The length of the chloroplast genome was 160,588 bp, with a typical quadripartite structure (GenBank accession no. OR900101). The large single-copy (LSC), small single-copy (SSC), and two inverted repeats (IRs) were 90,237 bp, 18,953 bp, and 25,699 bp in length, respectively. We annotated one hundred and thirty genes across the chloroplast genome, including 86 protein-coding genes (79 are unique), 37 tRNA genes (29 are unique), and eight rRNA genes (four are unique). Seventeen genes had one intron, and four were detected with two introns. The maximum likelihood phylogeny suggested that C. orthacantha, C. lamontii, C. sclerophylla, and C. hainanensis formed a clade with a high bootstrap value. This newly sequenced chloroplast genome assembly will aid in the population genetic and phylogenetic studies of Castanopsis species in the future.

Background and Aims Introgressive hybridization poses a challenge to taxonomic and phylogenetic understanding of taxa, particularly when there are high numbers of co-occurring, intercrossable species. The genus Quercus exemplifies this situation. Oaks are highly diverse in sympatry and cross freely, creating syngameons of interfertile species. Although a well-resolved, dated phylogeny is available for the American oak clade, evolutionary relationships within many of the more recently derived clades remain to be defined, particularly for the young and exceptionally diverse Mexican white oak clade. Here, we adopted an approach bridging micro- and macroevolutionary scales to resolve evolutionary relationships in a rapidly diversifying clade endemic to Mexico. Methods Ecological data and sequences of 155 low-copy nuclear genes were used to identify distinct lineages within the Quercus laeta complex. Concatenated and coalescent approaches were used to assess the phylogenetic placement of these lineages relative to the Mexican white oak clade. Phylogenetic network methods were applied to evaluate the timing and genomic significance of recent or historical introgression among lineages. Key Results The Q. laeta complex comprises six well-supported lineages, each restricted geographically and with mostly divergent climatic niches. Species trees corroborated that the different lineages are more closely related to other species of Mexican white oaks than to each other, suggesting that this complex is polyphyletic. Phylogenetic networks estimated events of ancient introgression that involved the ancestors of three present-day Q. laeta lineages. Conclusions The Q. laeta complex is a morphologically and ecologically related group of species rather than a clade. Currently, oak phylogenetics is at a turning point, at which it is necessary to integrate phylogenetics and ecology in broad regional samples to figure out species boundaries. Our study illuminates one of the more complicated of the Mexican white oak groups and lays groundwork for further taxonomic study. [ABSTRACT FROM AUTHOR]

Castanopsis chinensis (Spreng.) Hance is widespread in the subtropical forests of China. Castanopsis qiongbeiensis G.A. Fu and Castanopsis glabrifolia J. Q. Li & Li Chen are limited to the coastal beaches of Wenchang county in the northeast of Hainan Island, and have similar morphological characteristics to C. chinensis. It is supposed that C. qiongbeiensis and C. glabrifolia are closely related to C. chinensis. In the present study, the genetic differentiation, gene flow, and genetic relationship of C. chinensis, C. qiongbeiensis, and C. glabrifolia were investigated by using 15 nuclear microsatellite markers; a total of 308 individuals from 17 populations were sampled in the three species. The allelic variation of nuclear microsatellites revealed moderate but significant genetic differentiation (FCT = 0.076) among C. chinensis, C. qiongbeiensis, and C. glabrifolia, and genetic differentiation between C. chinensis and C. glabrifolia was larger than that between C. chinensis and C. qiongbeiensis. Demographic simulations revealed unidirectional gene flow from C. chinensis to C. glabrifolia and C. qiongbeiensis, which highlight dispersal from mainland to island. The isolation effect of Qiongzhou Strait increased the genetic differentiation of species on both sides of the strait; however, the differentiation was diminished by gene flow that occurred during the historical period when Hainan Island was connected to mainland China. Our results supported the argument that C. glabrifolia should be considered an independent species and argued that C. qiongbeiensis should be regarded as an incipient species and independent conservation unit. [ABSTRACT FROM AUTHOR]

Premise: During the last centuries, the area covered by urban landscapes is increasing all over the world. Urbanization can change local habitats and decrease connectivity among these habitats, with important consequences for species interactions. While several studies have found a major imprint of urbanization on plant–insect interactions, the effects of urbanization on seed predation remain largely unexplored. Methods: We investigated the relative impact of sunlight exposure, leaf litter, and spatial connectivity on predation by moth and weevil larvae on acorns of the pedunculate oak across an urban landscape during 2018 and 2020. We also examined whether infestations by moths and weevils were independent of each other. Results: While seed predation varied strongly among trees, seed predation was not related to differences in sunlight exposure, leaf litter, or spatial connectivity. Seed predation by moths and weevils was negatively correlated at the level of individual acorns in 2018, but positively correlated at the acorn and the tree level in 2020. Conclusions: Our study sets the baseline expectation that urban seed predators are unaffected by differences in sunlight exposure, leaf litter, and spatial connectivity. Overall, our findings suggest that the impact of local and spatial factors on insects within an urban context may depend on the species guild. Understanding the impact of local and spatial factors on biodiversity, food web structure, and ecosystem functioning can provide valuable insights for urban planning and management strategies aimed at promoting urban insect diversity. [ABSTRACT FROM AUTHOR]

Premise: Gynodioecy is a rare sexual system in which two genders (sensu Lloyd, 1980), cosexuals and females, coexist. To survive, female plants must compensate for their lack of siring capacity and male attractiveness. In European chestnut (Castanea sativa), an outcrossing tree, self‐pollination reduces fruit set in cosexual individuals because of late‐acting self‐incompatibility and early inbreeding depression. Could this negative sexual interaction explain the presence of females in this species? Methods: We studied gender variation in wild populations of European chestnut. In addition, we compared fruit set (the proportion of flowers giving fruits) and other key female fitness components as well as reproductive allocation between genders. We then performed emasculation experiments in cosexual trees, by removing nectar‐producing fertile male inflorescences. We also removed sterile but nectar‐producing male inflorescences from female trees, as a control. Results: We found a highly variable proportion of male‐sterile individuals in the wild in European chestnut. In the experimental plot, trees from each gender had similar size, flower density, and burr set, but different fruit set. Removing nectar‐producing male inflorescences from branches or entire trees increased fruit set in cosexual but not in female trees. Conclusions: These results show that self‐pollination impairs fruit set in cosexual trees. Female trees avoid these problems as they do not produce pollen but continue to attract pollinators thanks to their rewarding male‐sterile inflorescences, resulting in a much higher fruit set than in cosexuals. This demonstrates that even outcrossed plants can benefit from the cessation of self‐pollination, to the point that unisexuality can evolve. [ABSTRACT FROM AUTHOR]

Premise: Functional traits reflect species' responses to environmental variation and the breadth of their ecological niches. Fagus grandifolia and Oreomunnea mexicana have restricted distribution in upper montane cloud forests (1700–2000 m a.s.l.) in Mexico. These species were introduced into plantings at lower elevations (1200–1600 m a.s.l.) that have climates predicted for montane forests in 2050 and 2070. The aim was to relate morphological leaf traits to the ecological niche structure of each species. Methods: Leaf functional traits (leaf area, specific leaf area [SLA], thickness, and toughness) were analyzed in forests and plantings. Atmospheric circulation models and representative concentration pathways (RCPs: 2.6, 4.5, 8.5) were used to assess future climate conditions. Trait–niche relationships were analyzed by measuring the Mahalanobis distance (MD) from the forests and the plantings to the ecological niche centroid (ENC). Results: For both species, leaf area and SLA were higher and toughness lower in plantings at lower elevation relative to those in higher‐elevation forests, and thickness was similar. Leaf traits varied with distance from sites to the ENC. Forests and plantings have different environmental locations regarding the ENC, but forests are closer (MD 0.34–0.58) than plantings (MD 0.50–0.70) for both species. Conclusions: Elevation as a proxy for expected future climate conditions influenced the functional traits of both species, and trait patterns related to the structure of their ecological niches were consistent. The use of distances to the ENC is a promising approach to explore variability in species' functional traits and phenotypic responses in optimal versus marginal environmental conditions. [ABSTRACT FROM AUTHOR]

Fungi of the genus Cryphonectria are of special interest to tree pathologists because they cause bark disease in numerous species of the Fagaceae and Betulaceae. Despite this special attention, several Cryphonectria species were not recognized as such for a long time. This also affected the identity of eight isolates with outdated names that have been deposited in our laboratory since 1954. The present study reconstructs the history of the Cryphonectria cultures M282–M289 using primary bibliographic sources. To verify the species identity, all isolates were DNA barcoded and taxonomic affiliation was assessed using a phylogenetic approach. The taxonomic identity combined with the history of the isolates confirms that the chestnut blight epidemic (Cryphonectria parasitica) in Spain was caused by the planting of Asian chestnuts and that the first documented case of bark canker in 1940 was caused by Cryphonectria radicalis on Japanese chestnuts imported from France. The history of isolate M289 could be traced back to CBS 165.32, which proved to be the oldest preserved isolate of the rare Cryphonectria naterciae, confirming the presence of this fungus in Europe for at least 100 years. Based on the ITS barcoding of the 32‐year‐old type specimen, Cryphonectria decipiens must be reclassified as a later synonym of Cryphonectria radicalis. The reconstruction of the history of isolates M282–M289 takes us on a scientific journey from Italy to France, Spain and Portugal in the early twentieth century and offers new insights into the historical context of the invasion of Cryphonectria parasitica in Europe. [ABSTRACT FROM AUTHOR]

A new species of ambrosia beetle Indocryphalus chiyui Lin & Beaver (tribe Xyloterini LeConte, 1876) from Taiwan is described. The species is monogamous and xylomycetophagous, breeding in Castanopsis cuspidata var. carlesii (Hemsl.) Yamazaki (Fagaceae). Indocryphalus sordidus (Blandford) is recorded for the first time from Taiwan. Diagnostic characters, biological data and a key to species of Indocryphalus in Taiwan are provided. [ABSTRACT FROM AUTHOR]

• Forty-seven Quercus species (oaks) were recorded in South Africa. • Several taxa are naturalising and invading in South Africa. • Naturalisation is limited to the urban-wildland interface and riparian corridors. • Riverbank steepness can mediate oak naturalisation in a riparian corridor. • iNaturalist is a useful tool for studying the invasion ecology of alien species. Hundreds of species of alien trees have been introduced and widely cultivated in South Africa, and many species have become invasive. Despite their long residence time and widespread cultivation, little is known about the introduction history, current status, and invasion ecology of oaks (genus Quercus) in South Africa. This study reviews various aspects of the genus Quercus in South Africa. We determine the number of oak species present, assess their introduction status, map their distribution, highlight areas of putative naturalisation, and evaluate the usefulness of the community science platform iNaturalist for assessing these factors. We also conducted a field study to elucidate environmental factors that can mediate invasibility in a riparian zone. A literature search was conducted to review events associated with the introduction, cultivation and naturalisation of oaks and associated pests and diseases in South Africa. Records of Quercus species in South Africa were collated from herbaria, arboreta, the Southern African Plant Invader Atlas, the Plants of Southern Africa database and iNaturalist. A field study was conducted along the Eerste River in Stellenbosch to elucidate the role of environmental factors in mediating naturalisation. We found records of 47 Quercus taxa in South Africa which were refined to a list of 22 to 34 species likely present. The earliest record was for Quercus robur in 1656 but first records for most species date from between the late 1800s to the early 1900s. More than 99 % of presence and naturalisation records were of the ten commonly cultivated species. Quercus palustris, Q. robur , and Q. suber were categorised as invasive, and putative naturalisation was documented for Q. acutissima, Q. canariensis, Q. cerris, Q. ilex , and Q. nigra. Most naturalisation occurred at the urban-wildland interface and in riparian vegetation in Cape Town and Stellenbosch. Steepness of the riverbank was found to affect seedling recruitment in riparian areas. iNaturalist records shed new light on the presence, distribution, and introduction status of Quercus species in South Africa. However, taxonomic complexity and data quality complicated attempts to develop a robust inventory of Quercus in South Africa. Molecular studies are needed to achieve better resolution. Nonetheless, this study has greatly improved our understanding of the distribution and status of oaks in South Africa, with implications for their management. [ABSTRACT FROM AUTHOR]

Species of the genus Thelephora (Thelephorales, Thelephoraceae) are ectomycorrhizal symbionts of coniferous and broad-leaved plants, and some of them are well-known edible mushrooms, making it an exceptionally important group ecologically and economically. However, the diversity of the species from China has not been fully elucidated. In this study, we conducted a phylogenetic analysis based on the internal transcribed spacer (ITS) regions, using Maximum Likelihood and Bayesian analyses, along with morphological observations of this genus. Four new species from China are proposed, viz., T. dactyliophora, T. lacunosa, T. petaloides, and T. pinnatifida. In addition, T. sikkimensis originally described from India is reported for the first time from China. Thelephora dactyliophora, T. pinnatifida, and T. sikkimensis are distributed in subtropical forests and mainly associated with plants of the families Fagaceae and Pinaceae. Thelephora lacunosa and T. petaloides are distributed in tropical to subtropical forests. Thelephora lacunosa is mainly associated with plants of the families Fagaceae and Pinaceae, while T. petaloides is mainly associated with plants of the family Fagaceae. Line drawings of microstructures, color pictures of fresh basidiomes, and detailed descriptions of these five species are provided. [ABSTRACT FROM AUTHOR]

Quercus section Cyclobalanopsis represents a dominant woody lineage in East Asian evergreen broadleaved forests. Regardless of its ecological and economic importance, little is known about the genomes of species in this unique oak lineage. Quercus glauca is one of the most widespread tree species in the section Cyclobalanopsis. In this study, a high‐quality haplotype‐resolved reference genome was assembled for Q. glauca from PacBio HiFi and Hi‐C reads. The genome size, contig N50, and scaffold N50 measured 902.88, 7.60, and 69.28 Mb, respectively, for haplotype1, and 913.28, 7.20, and 71.53 Mb, respectively, for haplotype2. A total of 37,457 and 38,311 protein‐coding genes were predicted in haplotype1 and haplotype2, respectively. Homologous chromosomes in the Q. glauca genome had excellent gene pair collinearity. The number of R‐genes in Q. glauca was similar to most East Asian oaks but less than oak species from Europe and America. Abundant structural variation in the Q. glauca genome could contribute to environmental stress tolerance in Q. glauca. Sections Cyclobalanopsis and Cerris diverged in the Oligocene, in agreement with fossil records for section Cyclobalanopsis, which document its presence in East Asia since the early Miocene. The demographic dynamics of closely related oak species were largely similar. The high‐quality reference genome provided here for the most widespread species in section Cyclobalanopsis will serve as an essential genomic resource for evolutionary studies of key oak lineages while also supporting studies of interspecific introgression, local adaptation, and speciation in oaks. [ABSTRACT FROM AUTHOR]

Castanopsis orthacantha Franch. 1899 is one representative tree species distributed in the evergreen broad-leaved forests of southwestern China. This species is an important source of timber for manufacturing furniture, floors, and paper. It also plays a significant role in maintaining ecological balance and stability. To help with the genetic diversity assessment of C. orthacantha, we sequenced and assembled the first complete chloroplast genome. The length of the chloroplast genome was 160,588 bp, with a typical quadripartite structure (GenBank accession no. OR900101). The large single-copy (LSC), small single-copy (SSC), and two inverted repeats (IRs) were 90,237 bp, 18,953 bp, and 25,699 bp in length, respectively. We annotated one hundred and thirty genes across the chloroplast genome, including 86 protein-coding genes (79 are unique), 37 tRNA genes (29 are unique), and eight rRNA genes (four are unique). Seventeen genes had one intron, and four were detected with two introns. The maximum likelihood phylogeny suggested that C. orthacantha, C. lamontii, C. sclerophylla, and C. hainanensis formed a clade with a high bootstrap value. This newly sequenced chloroplast genome assembly will aid in the population genetic and phylogenetic studies of Castanopsis species in the future. [ABSTRACT FROM AUTHOR]

As a part of our systematic study on Castanopsis genus (Fagaceae), one new triterpene hydrolysable tannin (1) and two new phenol glucosides (2 and 3) were isolated from the leaves of Castanopsis eyrei (Champ. ex Benth.) Hutch. Compound 1 was identified as a triterpene hexahydroxydiphenoyl (HHDP) ester. This type of compounds has only been isolated from Castanopsis genus. The structures of 1-3 were elucidated by the combination of spectroscopic analysis (MS, 1 D and 2 D NMR) and chemical evidence. [ABSTRACT FROM AUTHOR]

[ Objective ] Castanopsis grandicicatricata N. H. Xia & D. H. Vuong is a species of Castanop- sis ( Fagaceae ) originally endemic to central and northern Vietnam , but now a scattered population was discovered in the Dawei Mountain area of the Pingbian Miao Autonomous County , Yunnan Province , Chi- na. This study aims to check its identity , to verify the close relatives from the literatures based on mor- phological speculation , and to show its systematic status. [ Methods ] Spacer ITS2 of nuclear rRNA genes 5.8S and 26S and chloroplast gene rbcL were used as molecular markers to reconstruct systematic tree. [ Results ] Morphologically , it could be distinguished from other Castanopsis species known in China by its cupule of 4.5-6.0 cm in diameter and the spine base was connate into tree-like branched bundles with a spheroid nut , where scar covering ca. 2 / 3 of the nut. The morphology-based speculation of the close rela- tives reported in the literatures was validated through phylogenetic tree restruction , C . mekongensis is one of its close relative. [ Conclusion ] C . grandicicatricata is a newly recorded species of Castanopsis from China. This new record holds significant implication for the study of the flora of southeast Yunnan and northern Vietnam.

The presence of Fagus x taurica Popl., a hybrid of two Fagus L. taxa known to be naturally distributed in Türkiye, has been detected in the natural deciduous-mixed forests of Bolu. Specimens were collected from Kökez Old Growth Fir Forest Nature Reserve Area, Bolu Kale Fındığı Nature Reserve Area, and Yedigöller National Park in Bolu province, northwest Türkiye. After the identification, specimens were compared with materials in the international herbaria. As a result of the examinations, the morphological features seen to be different from its parents are as follows: Young shoots are grayish-green in color, leaves have 7-13 pairs of lateral veins, are ovate or obovate, and their margins are dentate, and the cupula scales are subulate. It resembles F. orientalis Lipsky in terms of leaf characteristics and F. sylvatica L. in terms of cupula characteristics. In this article, a botanical description of the taxon, differences from the main species, distribution maps, and photos are given. Fagus x taurica is a new hybrid record for the vascular flora of Türkiye. With this new record, the number of Fagus sp. taxa in the flora of Türkiye has risen to 3.

Quercus is the largest genus of the family Fagaceae in the world and the second-largest in Vietnam, with approximately 50 species. However, the phylogeny study of the Quercus genus in Vietnam has yet to be thoroughly explored. In this study, we utilize the genome-wide singlenucleotide polymorphisms (SNPs) data obtained through Multiplexed Inter Simple Sequence Repeat Genotyping by sequencing (MIG-seq) to explore the phylogenetic relationships among Quercus species in Vietnam. The results of this study reveal that all Quercus species in Vietnam belong to subgenus Cerris and the phylogenetic analysis strongly supports the recognition of two infrageneric sections: Quercus and Ilex section for the Vietnamese Quercus. These results also confirm that the monophyly of Quercus in Vietnam is strongly supported by both morphological and molecular data. The results of this study also align entirely with previous research, indicating that Quercus species in Asia fall under the subgenus Cerris, comprising two sections: section Ilex and section Cyclobalanopsis. [ABSTRACT FROM AUTHOR]

Ypsolopha Latreille, 1796 (Lepidoptera, Ypsolophidae) is a genus comprised mostly of Holarctic micromoth species with a fairly broad range of larval hosts (e.g. Aceraceae, Rosaceae, and Fagaceae). The only previous record of herbivory on a representative of the South American genus Adesmia DC. (Fabaceae) was based on the discovery of Ypsolopha moltenii Vargas, 2018 larvae feeding on Adesmia verrucosa Meyen in the Andes of northern Chile. Further surveys revealed Adesmia atacamensis Phil. as another host for Y. moltenii, and Adesmia spinosissima Meyen as the single host of Ypsolopha sp. The genetic distance between DNA barcodes of the two micromoth species was 7.9–8.1% (K2P). These results suggest narrow host ranges for Adesmia-feeding Ypsolopha and highlight the need to further explore the taxonomic diversity of these micromoths in other South American environments. [ABSTRACT FROM AUTHOR]

Seed germination is among the most crucial and vulnerable stages in plant life cycles. Quercus marlipoensis is a critically endangered sclerophyllous oak. Only one population has ever been found worldwide in the tropical montane cloud forests of southeastern Yunnan, China, and it has shown difficulties with regeneration. However, its seed biological traits and key restrictive germination factors remain unknown. We investigate the impacts of scarification, temperature, and water potential on the seed germination of Q. marlipoensis. Results show that the seeds show typical epicotyl dormancy. The seed germination increased when removing part or all of the pericarp and part of the cotyledon (one-third and two-thirds). The seeds can germinate at 5 to 30 °C, but the highest T50 was achieved at 25 °C. When the water potential decreased from 0 to −1.0 MPa, the germination rate decreased but the germination time increased. Q. marlipoensis seeds are typically recalcitrant and highly sensitive to moisture loss, but the species can tolerate animal predation and low germination temperatures. The more frequent climatic extremes and droughts in the Indo-China region will severely degrade its natural habitats. Therefore, ex situ conservation to preserve its germplasm and introduce seedlings into a suitable habitat are essential for its conservation management. [ABSTRACT FROM AUTHOR]

This study presents a checklist and a key encompassing 11 species of Typhlodromus Scheuten (Acari: Phytoseiidae) from Syria, derived from materials collected in this study as well as previous reports. A brief redescription, including setal measurements and some other important characters used to discriminate phytoseiid species, is provided for each species examined. Notably, the species Typhlodromus (Anthoseius) intercalaris Livshitz & Kuznetsov is reported for the first time in Syria, and redescribed based on adult specimens collected from Quercus cerris L. and Quercus infectoria G. Olivier (Fagaceae) trees in Latakia governorate. The examined specimens of this species demonstrated variation in the presence or absence of preanal pores: (1) absent on both sides; (2) present on both sides; (3) present on the left side; and (4) present on the right side. This species was considered a junior synonym of T. (A.) invectus Chant in an earlier study without examination of their type materials. We tried to find the holotype T. (A.) invectus without success. However, according to their original description, T. (A.) intercalaris is distinguishable from T. (A.) invectus by having two pairs of setae on the sternal shield, as opposed to three pairs in the latter species. Therefore, the reason for the redescription provided here is to improve diagnosis and minimize any confusion regarding the species status of the Syrian specimens. This discovery holds significant implications for understanding the biodiversity of phytoseiids in the country. [ABSTRACT FROM AUTHOR]

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Quercus turbinella (section Quercus; Fagaceae) is an evergreen shrub characteristic in central Arizona and it concerns one of the most abundant and economically important genera of Quercus in the Northern Hemisphere. Here, we have sequenced the complete chloroplast genome to provide insight into the phylogenetic relationship of Q. turbinella. The whole genome is 161,208 bp in length with two inverted repeat regions of 25,827 bp each, which separate a large single-copy region of 90,552 bp and a small single-copy region of 19,002 bp. A total of 136 genes were annotated, including 88 protein-coding genes, eight ribosomal RNAs, and 40 transfer RNAs. The result of the maximum-likelihood phylogenetic analysis strongly suggested that Quercus turbinella had a close relationship to Quercus macrocarpa with strong bootstrap support. [ABSTRACT FROM AUTHOR]

Abstract Key message In arboriculture, the number and diversity of pollen donors can have a major impact on fruit production. We studied pollination insurance in hybrid chestnut orchards (C. sativa × C. crenata) provided by nearby wild European chestnuts (C. sativa) in southwestern France. Most fruits were sired by hybrid pollenizers rather than by wild chestnuts. When these hybrid pollenizers were too scarce, a frequent situation, pollen produced by wild chestnut trees did not compensate for the lack of compatible pollen and fertilization rates and fruit production collapsed. Context The demand for chestnuts has been increasing in recent years in many European countries, but fruit production is not sufficient to meet this demand. Improving pollination service in chestnut orchards could increase fruit production. Aims Investigate pollination service in chestnut orchards. Evaluate the contribution to pollination of trees growing in chestnut woods and forests. Methods We investigated five orchards planted with hybrid chestnuts (C. sativa × C. crenata) cultivars in southwestern France. We combined fruit set data, which provide information about pollination rate, with genetic data, which provide information about pollen origin. We used this information to estimate the contribution of nearby C. sativa forest stands to the pollination of each orchard. Results Pollination rates vary considerably, being fivefold higher in orchards comprising numerous pollen donors than in monovarietal orchards. Because of asymmetric hybridization barriers between hybrid and purebred cultivars, the surrounding chestnut forests provide very limited pollination insurance: less than 14% of the flowers in these monovarietal orchards had been pollinated by forest trees. Conclusion Because chestnut orchards are now increasingly relying on hybrid cultivars, surrounding wild European chestnut trees are no longer a reliable pollen source. To achieve maximal fruit set, efforts must therefore concentrate on orchard design, which should include enough cultivar diversity.

Lithocarpus, with >320 species, is the second largest genus of Fagaceae. However, the lack of a reference genome limits the molecular biology and functional study of Lithocarpus species. Here, we report the chromosome-scale genome assembly of sweet tea (Lithocarpus polystachyus Rehder), the first Lithocarpus species to be sequenced to date. Sweet tea has a 952-Mb genome, with a 21.4-Mb contig N50 value and 98.6% complete BUSCO score. In addition, the per-base consensus accuracy and completeness of the genome were estimated at 60.6 and 81.4, respectively. Genome annotation predicted 37,396 protein-coding genes, with repetitive sequences accounting for 64.2% of the genome. The genome did not undergo whole-genome duplication after the gamma (γ) hexaploidy event. Phylogenetic analysis showed that sweet tea diverged from the genus Quercus approximately at 59 million years ago. The high-quality genome assembly and gene annotation resources enrich the genomics of sweet tea, and will facilitate functional genomic studies in sweet tea and other Fagaceae species. [ABSTRACT FROM AUTHOR]

Background and aims: Phytolith analysis is a promising tool for paleovegetation reconstruction. However, compared with grass phytoliths, there are few studies that have classified the phytoliths of trees. Therefore, reliable definitions of phytolith types in woody plants and studies of representative woody phytoliths in soils are needed to provide an improved basis for reliable phytolith-based vegetation reconstruction. Methods: To explore the morphology of woody phytoliths and their preservation in soils, we described the phytolith morphology of 60 common broadleaved woody plants in the mid-subtropical zone of China, based initially on anatomical origin, and then on shape and finally on texture. We also for the first time established an index (R value) to explore the preservation of broadleaved woody phytoliths in soil in this region. Results: We divided the phytoliths of broadleaved woody plants into 6 major types and 35 sub-types. The 6 major types are: Epidermal Cell, Silicified stomata, Tracheary, Favose, Haircell, and Others. We found some degree of correspondence between different phytolith types and the parent plants. Fagaceae, Lauraceae, Magnoliaceae, Rosaceae, Anacardiaceae and Euphorbiaceae could be clearly distinguished from other families based on phytoliths. Only eight types of broadleaved woody phytoliths were present in the soils. Elongate attenuate, Elongate entire, and Polyhedral were better preserved in soils than the other types (Elongate entire attenuate, Tabular sinuate, Hair, Sclereid, and Favose). Conclusion: Our results provide a more accurate reference for broadleaved wood phytoliths in interpreting paleovegetation in this region. [ABSTRACT FROM AUTHOR]

Chloroplast genome diversity in cork oak (Quercus suber) is characterised by the occurrence of haplotypes that are akin to those found in other Mediterranean oak species, particularly in Q. ilex and Q. rotundifolia, suggesting the possible presence of an introgressed chloroplast lineage. To further investigate this pattern, we reconstructed chloroplast haplotypes by sequencing four chloroplast markers (cpDNA), sampled across 181 individuals and 10 taxa. Our analyses resulted in the identification of two diversified chloroplast haplogroups in Q. suber, corresponding to a geographically widespread lineage and an Afro-Iberian lineage. Time-calibrated phylogenetic analyses of cpDNA point to a Miocene origin of the two haplogroups in Q. suber, suggesting that the Afro-Iberian lineage was present in cork oak before the onset of glaciation periods. The persistence of the two haplogroups in the western part of the species distribution range may be a consequence of either ancient introgression events or chloroplast lineage sorting, combined with different fixation in refugia through glaciation periods. Our results provide a comprehensive insight on the origins of chloroplast diversity in these ecologically and economically important Mediterranean oaks. [ABSTRACT FROM AUTHOR]

Premise: Phylogeographical studies are fundamental for understanding factors that influence the spatial distribution of genetic lineages within species. Population expansions and contractions, distribution shifts, and climate changes are among the most important factors shaping the genetic compositions of populations. Methods: We investigated the phylogeography of an endemic oak, Quercus mexicana (Fagaceae), which has a restricted distribution in northeastern Mexico along the Sierra Madre Oriental and adjacent areas. Nuclear and chloroplast DNA microsatellite markers were used to describe the genetic diversity and structure of 39 populations of Q. mexicana along its entire distribution area. We tested whether population expansion or contraction events influenced the genetic diversity and structure of the species. We also modeled the historical distributional range of Q. mexicana (for the Mid Holocene, the Last Glacial Maximum, and the Last Interglacial) to estimate the extent to which climate fluctuations have impacted the distribution of this oak species. Results: Our results revealed high genetic diversity and low genetic structure in Q. mexicana populations. Ecological niche models suggested historical fluctuations in the distributional range of Q. mexicana. Historical range changes, gene flow, and physical barriers seem to have played an important role in shaping the phylogeographic structure of Q. mexicana. Conclusions: Our study indicates that the genetic structure of Q. mexicana may have been the result of responses of oak trees not only to heterogeneous environments present in the Sierra Madre Oriental and adjacent areas, but also to elevational and latitudinal shifts in response to climate changes in the past. [ABSTRACT FROM AUTHOR]

Oaks (Quercus sp.) are among the most ecologically and economically important woody Angiosperms of the northern hemisphere. Nowadays, the reduction of Quercus biodiversity is becoming a matter of global concern, and several oak species have been included in the IUCN Red List of Threatened Species. Consequently, characterization and preservation strategies for the oak germplasm are largely promoted. Thus, in this work, the genetic diversity existing among 87 different Quercus species was assessed using the RAPD markers, in order to better typify these specimens, to show the amazing DNA variability of this plant genus, and to confirm or infer new putative molecular correlations. Our data were discussed taking into consideration the phylogenetic and phylogeographic relationships previously proposed by the literature. In general, the obtained results corroborated that the evolutionary pattern of Quercus genus has been extremely intricate and continues to change rapidly, making it difficult to be fully resolved. The evidence collected in the present investigation would confirm the complex evolution of the oaks, due to their high migration capacity, divergence rate, and hybridization propensity. This research, performed on a so large series of species, represents a positive contribution for highlighting the genetic diversity within collections of Quercus germplasm and favouring ex-situ conservation programmes. [ABSTRACT FROM AUTHOR]

Ecological significance of dormancy in desiccation-sensitive seeds is poorly understood. Quercus exhibits mutually exclusive occurrence of physiological (PD) and epicotyl dormancy (ePD), with no reported co-occurrence or dormancy class in other genera. We aimed to understand the dormancy in three Castanopsis species and document desiccation sensitivity and germination patterns concerning the embryonic axis position. We hypothesized that Castanopsis acorns are recalcitrant and potentially dormant. Fresh and cold-stratified acorns of Castanopsis chinensis, Castanopsis purpurella, and Castanopsis sclerophylla were subjected to desiccation and germination. Seedling emergence and internal morphology was monitored following cold (CS) and warm (WS) stratification. Fresh acorns had radicles emerge only after CS but require WS for shoot emergence. Drying to 20% moisture content led to complete death. In C. purpurella and C. sclerophylla, the embryonic axis was near the scar, and germination occurred by cracking the pericarp near the scar, which contrasts with C. chinensis. Moderate drying relieved dormancy due to the mechanical resistance of the pericarp. All three acorns were desiccation-sensitive and dormant. This is the first explicit report on PD and ePD co-occurrence in desiccation-sensitive seeds, but literature surveys allow for inference of such coexistence. CS alleviated PD and WS relieved ePD. Winter temperatures break PD, and acorns germinate during spring, but shoot emergence is delayed until summer. Our results are instructive for research on the dormancy of desiccation-sensitive species and the reproduction of Fagaceae species in subtropical forests. [ABSTRACT FROM AUTHOR]

Main conclusion: This work mainly found that the stigma and style of Q. variabilis did not completely lose the specific recognition towards heterologous pollen, a fact which is different from previous studies. Quercus is the foundation species in the Northern Hemisphere, with extreme prevalence for interspecific hybridization. It is not yet entirely understood whether or how the pollen tube-female tissue interaction contributes to the “extensive hybridization” in oaks. Pollen storage conditions correlate with distant hybridization. We conducted hybridization experiments with Q. variabilis as female and Q. variabilis and Q. mongolica as male parents. And the differences in pollen tube (PT) development between intra- and distant interspecific hybridization were studied by fluorescence microscopy and scanning electron microscopy (SEM). Our results showed that –20 °C allowed pollen of both species to maintain some viability. Both Q. variabilis and Q. mongolica pollen germinated profusely on the stigmas. SEM results indicated that in the intraspecific hybridization, Q. variabilis pollen started to germinate at 6 h after pollination (hap), PTs elongated significantly at 12 hap, and entered the stigma at 24 hap. By contrast, Q. mongolica pollen germinated at 15 hap, and the PTs entered the stigma at 27 hap. By fluorescence microscopical studies it was observed that some PTs of Q. variabilis gathered at the style-joining at 96 hap, unlike the Q. mongolica which reached the style junction at 144 hap. The above results indicate that the abundant germination of heterologous pollen (HP) on the stigma and the “Feeble specificity recognition” of the stigma and transmitting tract to HP may create opportunities for the “extensive hybridization” of oaks. This work provides a sexual developmental reference for clarifying the causes of Quercus “extensive hybridization”. [ABSTRACT FROM AUTHOR]

Temperate forest species, including Fagus crenata Blume, have been experiencing distributional shifts during the climate oscillation throughout the Holocene epoch. This review describes the distinctive context of F. crenata populations at the northern range from the perspective of past distribution shifts, future expansion predictions, biotic and abiotic interactions in population establishment, forest vegetation characteristics, and genetic diversity during the expansion process. The current northern distribution limit of F. crenata is in southern Hokkaido and Okushiri Islands. Since 1900, a dozen of northern limit hypotheses has advocated the presence of restriction factors; however, the species shows signs of expanding its habitat northward at present. The current northern limit is not determined by physiological limitations because of the fact that artificial plantations of F. crenata grow well beyond its range. Several studies regarding climate scenarios have predicted species persistence in the future. Sociological studies revealed that a decline in vegetation units is observed from the southern to the northern populations on the Oshima Peninsula, Hokkaido. Also, vegetation on Okushiri Island includes remnants of warm temperate flora indicating a physiographic constraint of the F. crenata forest on the island, reflecting a past distributional shift. Most of the current northern marginal populations were revealed to be established at the time of large forest disturbance. The genetic diversity of local populations has been lost during the northward distribution shift due to the founder effect in the colonizing process. Then, the gene flow from rearward populations has dwindled by the completion of the population establishment. [ABSTRACT FROM AUTHOR]

Castanopsis is one of the most common genus of trees in subtropical evergreen broad-leaved forests and tropical monsoon rainforests in China. Castanopsis hainanensis and Castanopsis wenchangensis are endemic to Hainan Island, but they were once confused as the same species due to very similar morphologies. In this study, nuclear microsatellite markers and chloroplast genomes were used to delimit C. hainanensis and C. wenchangensis. The allelic variations of nuclear microsatellites revealed that C. hainanensis and C. wenchangensis were highly genetically differentiated with very limited gene admixture. Both showed higher genetic diversity within populations and lower genetic diversity among populations, and neither had further population genetic structure. Furthermore, C. wenchangensis and C. hainanensis had very different chloroplast genomes. The independent genetic units, very limited gene admixture, different distribution ranges, and distinct habitats all suggest that C. wenchangensis and C. hainanensis are independent species, thus they should be treated as distinct conservation units. [ABSTRACT FROM AUTHOR]

Gnomoniopsis castaneae is internationally recognized as a destructive pathogen of chestnut species. Primarily associated with nut rot, it has also been associated with branch and stem cankers of chestnut and as an endophyte of multiple additional hardwood species. The present study evaluated implications of the recently reported United States presence of the pathogen for domestic Fagaceae species. Stem inoculation assays of Castanea dentata, C. mollissima, C. dentata x C. mollissima, and Quercus rubra (red oak) seedlings were utilized to examine the cankering ability of a regional isolate of the pathogen. The pathogen induced damaging cankers in all assessed species and significant stem girdling in all chestnut species. No previous study has associated the pathogen with damaging infection in Quercus species, and its presence in the United States has the potential to compound ongoing chestnut recovery programs and oak regeneration problems within forest systems. [ABSTRACT FROM AUTHOR]

Fagus pashanica is an endangered and endemic tree species in China. To understand its genetic diversity and structure for effective conservation, we used next-generation sequencing data to develop a set of microsatellite markers. Twenty-three of the 68 designed loci were successfully amplified. Fifteen polymorphic loci with clear peaks were selected for further analyses in three F. pashanica populations sampled from Nanjiang, Wangcang and Pingwu counties in Sichuan Province, China. The number of alleles per locus ranged from two to 11. The levels of observed and expected heterozygosity ranged from 0.033– 0.852 and 0.033–0.787, respectively. All 23 loci were also successfully amplified in F. longipetiolata and F. lucida, and 19 were successfully amplified in F. engleriana. These microsatellite markers will be useful for population genetic studies of F. pashanica and other Fagus species. [ABSTRACT FROM AUTHOR]

Key message: In arboriculture, the number and diversity of pollen donors can have a major impact on fruit production. We studied pollination insurance in hybrid chestnut orchards (C. sativa × C. crenata) provided by nearby wild European chestnuts (C. sativa) in southwestern France. Most fruits were sired by hybrid pollenizers rather than by wild chestnuts. When these hybrid pollenizers were too scarce, a frequent situation, pollen produced by wild chestnut trees did not compensate for the lack of compatible pollen and fertilization rates and fruit production collapsed. Context: The demand for chestnuts has been increasing in recent years in many European countries, but fruit production is not sufficient to meet this demand. Improving pollination service in chestnut orchards could increase fruit production. Aims: Investigate pollination service in chestnut orchards. Evaluate the contribution to pollination of trees growing in chestnut woods and forests. Methods: We investigated five orchards planted with hybrid chestnuts (C. sativa × C. crenata) cultivars in southwestern France. We combined fruit set data, which provide information about pollination rate, with genetic data, which provide information about pollen origin. We used this information to estimate the contribution of nearby C. sativa forest stands to the pollination of each orchard. Results: Pollination rates vary considerably, being fivefold higher in orchards comprising numerous pollen donors than in monovarietal orchards. Because of asymmetric hybridization barriers between hybrid and purebred cultivars, the surrounding chestnut forests provide very limited pollination insurance: less than 14% of the flowers in these monovarietal orchards had been pollinated by forest trees. Conclusion: Because chestnut orchards are now increasingly relying on hybrid cultivars, surrounding wild European chestnut trees are no longer a reliable pollen source. To achieve maximal fruit set, efforts must therefore concentrate on orchard design, which should include enough cultivar diversity. [ABSTRACT FROM AUTHOR]

Chestnut, Castanea sativa Miller (Fagales: Fagaceae), is an ecologically and economically important tree species of the forest ecosystem in Southern Europe, North-Western Europe, Western Asia, North Africa, and the Caucasus. The distributional range of chestnut in Europe has been highly modified by humans since ancient times. Biotic and abiotic factors have dramatically changed its distribution. Historic anthropogenic range expansion makes it difficult to identify habitat requirements for natural stands of chestnut. In the Caucasus, natural stands of chestnut survived in glacial forest refugia and landscapes that have been difficult for humans to colonize. To identify the species reliable habitat requirements, we estimated the relationship between climatic variables and 620 occurrence locations of natural chestnut stands from the Caucasus and validated the model using GBIF data from outside the Caucasus. We found that our best model is reasonably accurate and the data from the Caucasus characterize chestnut stands throughout the species range well. [ABSTRACT FROM AUTHOR]

Castanopsis hystrix Hook. f. & Thomson ex A. DC. 1863 (Fagaceae) is an evergreen broad-leaved tree with high economic and ecological value. In this study, the complete chloroplast genome of C. hystrix was sequenced, assembled and annotated. The plastome (plastid genome) of C. hystrix was 160,624 bp in size, consisting of a pair of inverted repeats (IRs, 25,699 bp), a large-single-copy (LSC, 90,276 bp) region, and a small-single-copy (SSC, 18,950 bp). The overall GC content of C. hystrix was 36.8%. A total of 133 genes were annotated, including 88 protein-coding genes (PCG), 37 transfer RNA genes (tRNA), and eight ribosomal RNA genes (rRNA). A maximum likelihood analysis showed that the Castanopsis species form a monophyletic clade. C. hystrix is most closely related to C. tibetana with 100% bootstrap support value. The result enriches the genomic data for the genus Castanopsis, which will contribute to future studies in phylogenetics and evolution.

Lithocarpus litseifolius (Hance) Chun 1837 is an evergreen tree of Fagaceae, which can be used as sweet tea, natural sweetener, and precious medicinal material. The complete chloroplast genome of L. litseifolius was sequenced and its phylogenetic relationship was analyzed in this study. The chloroplast genome of L. litseifolius has a circular structure with a length of 161,322 bp, and it contains a pair of inverted repeat regions (IRs 25,897 bp), a large single copy (LSC 90,551 bp), and a small single copy (SSC 18,977 bp). There were 131 genes identified, including 37 tRNA, 8 rRNA, and 86 mRNA genes. Phylogenetic analysis of 23 species of Fagaceae indicated that Lithocarpus is monophyletic with strong bootstrap, and L. litseifolius is genetically closely related to Lithocarpus polystachyus.

The phylogenetic status of Quercus subg. Cyclobalanopsis has long been controversial and the interspecific relationships of some species are unclear. At present, chloroplast genomes have been used to solve the phylogenetic problems of subg. Quercus and Castanea in the Fagaceae, but there are few researches on solving the phylogenetic problems of Quercus subg. Cyclobalanopsis with chloroplast genome information. To reveal the chloroplasts genome characteristics and phylogenetic relationships of Quercus ningangensis, Q. oxyodon, Q. gambleana and Q. neglecta. In this study, mature leaves of the above four species of Quercus subg. Cyclobalanopsis were selected for next-generation sequencing, and the chloroplast genome structure and characteristics were analyzed, phylogeny was studied in combination with related taxa. The results were as follows: (1) The chloroplast genome sequences of Q. ningangensis, Q. oxyodon, Q. gambleana and Q. neglecta were 160 906, 160 883, 160 832, 160 784 bp, respectively. They all encoded 133 genes, including 88 protein-coding genes, 37 tRNA genes and 8 rRNA genes. (2) The codons ending in A/T were preferred by the four species of Quercus subg. Cyclobalanopsis, and the variation regions of plastid genome mainly existed in non-coding sequences. (3) According to IR boundary analysis, ycf1 pseudogene was found in four species of Quercus subg. Cyclobalanopsis and expanded in IRb/SSC regions. (4) Phylogenetic analysis showed that Fagus and Trigonobalanus were differentiated early in Fagaceae, while subg. Quercus did not form a monophyly. The results of phylogenetic tree based on chloroplast genome were consistent with the nuclear marker plasmid markers. Interspersed between Ilex group and Cerris group in subg. Quercus. (5) The Flora of China and some local flora treated Q. gambleana as a separate species, while ZHOU Zhekun and DENG Min et al. treated Q. gambleana as a subspecies according to the characteristics of leaves. The phylogenetic status of Q. gambleana is still controversial. Based on the chloroplast genome information and previous morphological analysis results, the present study supported the idea that Q. gambleana existed as an independent species. This study provides basic data for discussing the phylogenetic status of the Quercus subg. Cyclobalanopsis, the division of its groups, and the resolution of doubtful relationships among them.

A new species of stone oak, Lithocarpus tapanuliensis Harapan, W.H.Tan, Nurainas & Strijk from South Tapanuli, North Sumatra, Indonesia is described. We provide colour photographs, a distribution map and a new IUCN conservation status assessment for inclusion on the global Red List. The unique cupule morphology, particularly the shape, placement and distinctness of the cupule protuberances, are distinctive from other Lithocarpus species in the region. Ecological interactions (e.g. consumption and nesting) with Tapanuli orangutans were recorded in the field. [ABSTRACT FROM AUTHOR]

In the family Fagaceae, fertilization is delayed by several weeks to 1 year after pollination, leading to 1‐ or 2‐year fruiting species depending on whether fruiting occurs in the same or the next year after flowering. To investigate physiological responses underlying the regulation of delayed fertilization, we monitored seasonal changes in genome‐wide gene expression in tissues including leaves and buds over 2 years under natural conditions in one‐ (Quercus glauca) and 2‐year fruiting species (Lithocarpus edulis). Genes associated with metabolic changes in response to winter cold, photosynthesis and cell proliferation, which are essential for survival and growth, showed highly conserved seasonal expression profiles between species. However, seasonal expression profiles diverged between species in genes associated with pollination, an important process contributing to the origin and maintenance of the reproductive barrier between plant species. By comparing seasonal progression of ovule development and gene expression in pistillate flowers, we revealed that ovules started developing after winter in the 2‐year fruiting species, which could be linked to the activation of genes involved in fertilization and female gametophyte development after winter. These findings suggest that the 2‐year fruiting species may have evolved a requirement of winter cold to prevent fertilization before winter and facilitate fertilization and embryo development in the following spring when temperature rises. This study offers new possibilities to explore the evolution of reproductive strategies in Fagaceae. [ABSTRACT FROM AUTHOR]

Cryphonectria carpinicola is an ascomycetous fungus that has been regularly found in its asexual form on European hornbeam (Carpinus betulus) in Europe over the past two decades. Here we describe the discovery of C. carpinicola in Japan and report for the first time its sexual state on Carpinus species. No symptomatic trees were observed, but stromata were found saprotrophically on broken branches of Carpinus species on the forest floor. The sexual structures of C. carpinicola resembled that of other Cryphonectria species and strongly resembled those of the closely related species C. radicalis. A phylogenetic tree based on the internal transcribed spacer sequences showed monophyly for the Japanese and European isolates of C. carpinicola. Further studies on the distribution and host range of C. carpinicola in Japan and on the life history strategies of this fungus are needed. [ABSTRACT FROM AUTHOR]

Dominant groups and rare groups often coexist in forests. Dominate plant families generally have more species diversity and occupy most of the biomass. However, their effects on community construction and species diversity maintenance remain to be studied. This study aims to investigate this question by using the two dominant plant families in a Chinese subtropical forest (Lauraceae and Fagaceae). In this study, 22 forest dynamic plots were established in the forest distribution area of Daming Mountain Nature Reserve at an elevation of 300–1400 m. We explored the elevational change in the community structure and its relationship with Lauraceae and Fagaceae using generalized additive models (GAM) and a regression analysis. Then we used a correlation analysis to describe the relationship between environmental factors and the community structure. Our results showed the species diversity index showed a hump-shape trend along the elevation, and the total basal area showed no significant change along the elevation. The richness of Lauraceae and Fagaceae showed a positive correlation with the species diversity, but only the richness of Fagaceae showed a positive correlated with the total basal area. Species diversity was positively correlated with soil total nitrogen and soil organic matter. Species diversity and the total basal area were negatively correlated with the soil pH. In summary, Lauraceae and Fagaceae are correlated for community structure, and this correlation is not affected by elevation. Fagaceae has played a more important role than Lauranceae. This study highlights the impact of dominant plant families on the forest community assembly along the elevational transect. [ABSTRACT FROM AUTHOR]

Castanopsis hystrix Hook. f. & Thomson ex A. DC. 1863 (Fagaceae) is an evergreen broad-leaved tree with high economic and ecological value. In this study, the complete chloroplast genome of C. hystrix was sequenced, assembled and annotated. The plastome (plastid genome) of C. hystrix was 160,624 bp in size, consisting of a pair of inverted repeats (IRs, 25,699 bp), a large-single-copy (LSC, 90,276 bp) region, and a small-single-copy (SSC, 18,950 bp). The overall GC content of C. hystrix was 36.8%. A total of 133 genes were annotated, including 88 protein-coding genes (PCG), 37 transfer RNA genes (tRNA), and eight ribosomal RNA genes (rRNA). A maximum likelihood analysis showed that the Castanopsis species form a monophyletic clade. C. hystrix is most closely related to C. tibetana with 100% bootstrap support value. The result enriches the genomic data for the genus Castanopsis, which will contribute to future studies in phylogenetics and evolution. [ABSTRACT FROM AUTHOR]

Global changes in nutrient deposition rates and habitat fragmentation are likely to have profound effects on plant communities, particularly in the nutrient-limited systems of the tropics and subtropics. However, it remains unclear how increased phosphorus (P) supply affects seedling growth in P-deficient subtropical fragmented forests. To explore this, we applied P to 11 islands in a subtropical Chinese archipelago and examined the results in combination with a contemporary greenhouse experiment to test the influence of P addition on seedling growth and survival. We measured the growth (i.e., base area) and mortality rate of seedlings for one arbuscular mycorrhizal (AM) and one ectomycorrhizal (EcM) tree species separately and calculated their relative growth rate and mortality when compared with P addition and control treatment on each island. We also measured three functional traits and the biomass of seedlings in the greenhouse experiment. Results showed that P addition significantly increased the mortality of AM and EcM seedlings and reduced the growth rate of EcM seedlings. The relative growth rate of AM seedlings, but not EcM seedlings, significantly decreased as the island area decreased, suggesting that P addition could promote the relative growth rate of AM seedlings on larger islands. The greenhouse experiment showed that P addition could reduce the specific root length of AM and EcM seedlings and reduce the aboveground and total biomass of seedlings, indicating that P addition may affect the resource acquisition of seedlings, thereby affecting their survival and growth. Our study reveals the synergistic influence of habitat fragmentation and P deposition, which may affect the regeneration of forest communities and biodiversity maintenance in fragmented habitats. [ABSTRACT FROM AUTHOR]

Quercus (oaks) is a large and important genus of woody angiosperms occurring in a wide range of environments and often occupying a dominant position in temperate forests of the Northern Hemisphere or being a minor component in some subtropical and tropical forests. A reliable determination of fossil dispersed oak pollen requires combined light, scanning electron (SEM) and transmission electron microscopy (TEM) studies and relevant comparative data on extant oak species. We provide SEM and TEM data on 22 extant Quercus spp. representing all sections of the genus. The main objectives of our study were to clarify the nature of the so-called geniculus, a characteristic equatorial bulge in the exine of the colpus found in many oak species, and to test previous hypotheses about the structural basic units of the exine in Quercus. Our ontogenetic study and oxidative experiment involving several Quercus spp. and one Trigonobalanus sp. resulted in a more accurate interpretation of the nature of the geniculus and exine elements, their different developmental states and, therefore, their more reliable application in the systematics and evolution of the genus Quercus and Fagaceae in general. [ABSTRACT FROM AUTHOR]