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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., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

A new species of mealybug (Hemiptera: Coccomorpha: Pseudococcidae), Paraputo nanlingensis Li & Wu, sp. n., is recorded on Fagaceae from Guangdong Province, China. The adult female is described and illustrated, and an identification key is provided to separate the adult females of Paraputo species known from China.

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.

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.

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 × 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., Competing Interests: The author(s) declare no conflict of interest.

[ 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.

Main Conclusion: The pistillate flowers of Lithocarpus dealbatus show two pollen tube (PT) arresting sites (the style-joining and micropyle) within the pistil during the postpollination-prezygotic stage. The PT, arrested at the pre-ovule stage, enhanced PT competition allowing the most compatible PTs to enter the ovary to ensure the highest fertilization success. During the shift from animal pollination to wind pollination, plants require a series of changes in reproductive traits. The mode of pollination is striking labile in Fagaceae. Lithocarpus is insect pollinated and is closely related to wind-pollinated Quercus. Little is known about the sexual reproduction of Lithocarpus. This study aimed to reveal the sexual reproduction of Lithocarpus dealbatus and to explore the evolutionary pattern of the key sexual reproduction traits to better understand their possible role in labile pollination. We found that after pollination, L. dealbatus PTs grew slowly in the style reaching style-joining in mid-January of the second year; then PT growth was arrested at style-joining for four months. Only two to three PTs resumed growth in mid-May to reach the micropyle, where PT growth ceased for one month before one PT resumed growth and passed through the micropyle to the embryo sac. Fagaceae showed a generalized mating system. Vast pollen production, small-sized pollen grains, long stigmatic receptive time, and reduced perianth were compatible with beetle pollination syndrome, representing the plesiomorphic status in Fagaceae. A large stigmatic surface and dry pollen grains linked to wind pollination might be independently derived several times in fagaceous lineages. Beetle pollination syndrome can cope with the uncertainty of pollinators to ensure conspecific pollen capture, which represents pre-adaptation status and has a selective advantage when conditions change, favouring wind pollination. The arrest of the PT at style-joining is a unique mechanism in later derived fagaceous lineages to enhance PT competition and promote outcrossing., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The present study attempts to characterise Fagaceae kernels as a promising source of nutritional compounds for potential use as novel food ingredients. Thus, the proximate and mineral composition of some kernels (beech achene-BA, sessile oak acorn-SOA, turkey oak acorn-TOA, and red oak acorn-ROA), total phenolic content, individual polyphenols, and cytotoxicity of their aqueous extracts, respectively, the fatty acid composition of kernel oils were investigated using physicochemical and analytical techniques. Results revealed that BAK is rich in lipid and protein, OAKs in carbohydrates. All tested kernels contain high oleic-linoleic acid oils. BAK is abundant in phenolic acids, OAKs in hydrolysable tannins. Only BA and SOA kernels exert cytotoxicity against human fibroblasts. In all kernels, macroelements are dominated by K and microelements by Cu, Mn, and Fe. In conclusion, BA and OA kernels could be alternatively used as protein-rich, respectively, starch-rich ingredients in food., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

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 dominant species of a biome can be regarded as its genuine indicator. Evergreen broadleaved forests (EBLFs) in subtropical East Asia harbor high levels of species biodiversity and endemism and are vital to regional carbon storage and cycling. However, the historical assembly of this unique biome is still controversial. Fagaceae is the most essential family in East Asian subtropical EBLFs and its dominant species are vital for the existence of this biome. Here, we used the dominant Fagaceae species to shed light on the dynamic process of East Asian subtropical EBLFs over time. Our results indicate high precipitation in summer and low temperature in winter are the most influential climatic factors for the distribution of East Asian subtropical EBLFs. Modern East Asian subtropical EBLFs did not begin to appear until 23 Ma, subsequently experienced a long-lasting development in the Miocene and markedly deteriorated at about 4 Ma, driven jointly by orogenesis and paleoclimate. We also document that there is a lag time between when one clade invaded the region and when its members become dominant species within the region. This study may improve our ability to predict and mitigate the threats to biodiversity of East Asian subtropical EBLFs and points to a new path for future studies involving multidisciplinary methods to explore the assembly of regional biomes., (© 2022 Institute of Botany, Chinese Academy of Sciences.)

This document summarizes a study that used ensemble modeling to predict the suitable habitat for Quercus oblongata, a species of oak tree found in the western Himalayan region. The study used environmental variables and occurrence records to build the model, which included four algorithms. The study identified the most important environmental variables and determined the suitable habitat areas for Q. oblongata. The findings have implications for future exploration and conservation efforts. The document also provides additional resources for further reading on related topics. [Extracted from the article]

AbstractQuercus 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.

Fagaceae is a family of flowering plants widely distributed in the Northern Hemisphere, including deciduous and evergreen trees and shrubs. Species of Pestalotiopsis are well-known agents of leaf spot diseases, but targeted sampling on Fagaceae is still missing. To determine the diversity of Pestalotiopsis species associated with Fagaceae leaf spot in China, investigations were conducted in the main areas of Fagaceae distribution from 2016 to 2021. Diseased leaf tissues were collected, and fungal isolates were obtained from leaf spots. In the present study, 43 isolates of Pestalotiopsis were studied based on combined morphology and phylogeny. As a result, 10 new species were identified, viz. , Pestalotiopsis anhuiensis , P. castanopsidis , P. changjiangensis , P. cyclobalanopsidis , P. foliicola , P. guangxiensis , P. guizhouensis , P. lithocarpi , P. shaanxiensis , and P. silvicola , and six new host records were recognized. IMPORTANCE Pestalotiopsis is a common fungal genus inhabiting plant tissues as endophytes, pathogens, and saprophytes. Fagaceae is a plant family including many important tree species, such as Castanea mollissima and Quercus spp. In this study, diseased leaves of Fagaceae in China were investigated, and 16 Pestalotiopsis species were identified based on morphology and phylogeny of combined loci of internal transcribed spacers (ITS), the translation elongation factor 1-α ( tef1 ), and the beta-tubulin ( tub2 ) genes. Among these, 10 new species were found, and six new host records were revealed. Our study significantly updates the taxonomy of Pestalotiopsis and enhances our understanding of leaf diseases of Fagaceae hosts.

Castanopsis fordii Hance 1884 is a typical evergreen broad-leaved forest plant in the south subtropical and middle subtropical regions of China. It has high utilization value in wood production and soil erosion protection. Here, we first reported and characterized the complete chloroplast (cp) genome sequence of C. fordii based on Illumina paired-end sequencing data. The complete cp genome sequence of C. fordii was 160,853 base pairs (bp) in length which contained two inverted repeats (IRs) of 25,699 bp separated by a large single-copy (LSC) and a small single copy (SSC) of 90,474 bp and 18,981 bp, respectively. The cpDNA contained 129 genes, comprising 85 protein-coding genes, 36 tRNA genes, 8 rRNA genes. The overall GC content of the plastome was 36.8%. Phylogenetic analysis base on 14 chloroplast genomes indicated that C. fordii was closely related to the species C. tibetana and C. concinna in Fagaceae.

Fagaceae species are increasingly used as models to elucidate the process and mechanism of adaptation and speciation by integrating ecology, evolution and genomics. The genus Castanopsis belongs to the family Fagaceae and is mainly distributed across subtropical and tropical Asia. In the present study, we reported the first chromosome-scale genome assembly of Castanopsis tibetana, a common species of evergreen broadleaved forests in subtropical China. The combination of Nanopore sequencing and Hi-C technologies enabled a high-quality genome assembly. The final assembled genome size of C. tibetana was 878.6 Mb (97.6% of the estimated genome size), consisting of 477 contigs with an N50 length of 3.3 Mb. The benchmarking universal single-copy orthologue (BUSCO) assessment indicated a completeness of 93.0%. Hi-C scaffolding generated 12 pseudochromosomes, representing 98.7% of the assembled genome. Subsequently, 40,937 protein-coding genes were predicted and 90.04% of them were functionally annotated. More than 476.9 Mb of repetitive sequences (54.3% of the genome) were identified, and the percentage of the genome covered by TE elements was 39.98%. Comparative genomics analysis revealed that C. tibetana was most closely related to Castanea mollissima and diverged at 18.48 Ma, and that C. tibetana has undergone considerable gene family expansion and contraction. Evidence of positive selection was detected in 53 genes, which showed different arrangement pattern compared to Quercus robur. The chromosome-scale genome assembly of C. tibetana will expand Fagaceae genome resources across the family and provide a powerful comparative framework to study the adaptation and evolution of Fagaceae trees., (© 2021 John Wiley & Sons Ltd.)

The full-grown larval stage of Curculio mexicanus Gibson is described and illustrated for the first time. The larvae were collected in fruits (acorns) of several species of Quercus L. (Fagaceae): Q. pinnativenulosa C. H. Mull, Q. xalapensis Bonpl., Q. germana Schltdl. & Cham., Q. candicans Née and Q. polymorpha Schltdl. & Cham; all species with wide distribution in the Sierra Madre Oriental and representative of the mountain mesophilic forest of Xalapa, Veracruz, Mexico. The record of Curculio mexicanus in Veracruz constitutes the first report for this species, as previously it was only known in Chiapas, Durango, Guerrero, Nayarit, Oaxaca and Sonora, in Quercus magnoliifolia Née (Q. macrophylla Née). Of those five mentioned host species of Quercus: Q. xalapensis and Q. germana are listed as vulnerable; thus, it is important to carry out research concerning this interaction in order to develop conservation strategies for these oaks as well as correct management and control of the weevils. [ABSTRACT FROM AUTHOR]

American chestnut ( Castanea dentata ) is a deciduous tree species of eastern North America that was decimated by the introduction of the chestnut blight fungus ( Cryphonectria parasitica ) in the early 20th century. Although millions of American chestnuts survive as root collar sprouts, these trees rarely reproduce. Thus, the species is considered functionally extinct. American chestnuts with improved blight resistance have been developed through interspecific hybridization followed by conspecific backcrossing, and by genetic engineering. Incorporating adaptive genomic diversity into these backcross families and transgenic lines is important for restoring the species across broad climatic gradients. To develop sampling recommendations for ex situ conservation of wild adaptive genetic variation, we coupled whole-genome resequencing of 384 stump sprouts with genotype-environment association analyses and found that the species range can be subdivided into three seed zones characterized by relatively homogeneous adaptive allele frequencies. We estimated that 21 to 29 trees per seed zone will need to be conserved to capture most extant adaptive diversity. We also resequenced the genomes of 269 backcross trees to understand the extent to which the breeding program has already captured wild adaptive diversity, and to estimate optimal reintroduction sites for specific families on the basis of their adaptive portfolio and future climate projections. Taken together, these results inform the development of an ex situ germplasm conservation and breeding plan to target blight-resistant breeding populations to specific environments and provides a blueprint for developing restoration plans for other imperiled tree species., Competing Interests: Competing interests statement:The authors declare no competing interest.

The sweet chestnut ( Castanea sativa Mill.) is subject to the progressive disappearance of its traditional chestnut groves. In the northern part of Italy, where distribution of the sweet chestnut is fragmented, many local varieties continue to be identified mostly by oral tradition. We characterised by SSRs eleven historically recognised varieties of sweet chestnut in the area surrounding Lake Como, with the goal of giving a genetic basis to the traditional classification. We performed classical analysis about differentiation and used Bayesian approaches to detect population structure and to reconstruct demography. The results revealed that historical and genetic classifications are loosely linked when chestnut fruits are just "castagne", that is, normal fruits, but increasingly overlap where "marroni" (the most prized fruits) are concerned. Bayesian classification allowed us to identify a homogeneous gene cluster not recognised in the traditional assessment of the varieties and to reconstruct possible routes used for the propagation of sweet chestnut. We also reconstructed ancestral relationships between the different gene pools involved and dated ancestral lineages whose results fit with palynological data. We suggest that conservation strategies based on a genetic evaluation of the resource should also rely on traditional cultural heritage, which could reveal new sources of germplasm.

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]