Search Results (39)

Accurate estimation of aboveground biomass (AGB) in tree–shrub communities is critical for quantifying forest ecosystem productivity and carbon sequestration potential. Although generalized allometric equations offer expediency in natural forest AGB estimation, their neglect of interspecific variability introduces methodological pitfalls. Precise AGB prediction necessitates resolving two biological constraints: phylogenetic conservation of allometric coefficients and ontogenetic regulation of scaling relationships. This study establishes an integrated framework combining the following: (1) phylogenetic signal detection (Blomberg’s K/Pagel’s λ) across 157 species’ allometric equations, revealing weak but significant evolutionary constraints (λ = 0.1249, p = 0.0027; K ≈ 0, p = 0.621); (2) hierarchical error decomposition of 9105 stems in a Mt. Wuyishan forest dynamics plot (15 species), identifying family-level error stratification (e.g., Theaceae vs. Myrtaceae, Δerror > 25%); (3) ontogenetic trajectory analysis of Castanopsis eyrei between Mt. Wuyishan and Mt. Huangshan, demonstrating significant biomass deviations in small trees (5–15 cm DBH, p < 0.05). Key findings resolve the following hypotheses: (1) absence of strong phylogenetic signals validates generalized models for phylogenetically diverse communities; (2) ontogenetic regulation dominates error magnitude, particularly in early developmental stages; (3) differential modeling is recommended: species-specific equations for pure forests/seedlings vs. generalized equations for mixed mature forests. This work establishes an error hierarchy: ontogeny > taxonomy > phylogeny, providing a mechanistic basis for optimizing forest carbon stock assessments. Full article

Angiosperms are the largest group of land plants with ~375,000 species, which are classified into ~416 families and ~13,000 genera; they exhibit tremendous morphological and physiological diversities and are important members of diverse terrestrial and aquatic ecosystems. Angiosperms have attracted continuous efforts to describe and understand these diversities in a framework of interrelationships—the phylogeny, which provides strong support for angiosperm classifications and relies on morphological, anatomical, and increasing molecular markers. Today, great advances in sequencing technology have led to the generation of tens of thousands of gene sequences for individual species, facilitating angiosperm phylogenetic reconstruction with high resolution at both deep and shallow levels. In this review, we present recent insights into angiosperm phylogeny based on relatively large numbers of nuclear genes, encompassing the ordinal scale of early-divergent and backbone branches, eudicots and their major subclades, asterids and rosids, as well as monocots. We further delve into intra-order cases such as Caryophyllales (Eudicots) and Alismatales (Monocots), along with intra-family relationships for some of the largest families (e.g., Asteraceae, Orchidaceae, Fabaceae, and Poaceae) and those with economic importance (such as Brassicaceae, Solanaceae, Cucurbitaceae, and Rosaceae). Furthermore, we briefly highlight the importance of nuclear phylogeny in addressing key evolutionary questions, including the origin and divergence of angiosperms, the evolution of morphological and other characters, gene duplication and other aspects of gene family evolution. Finally, we discuss possible future trends of angiosperm phylogenomics. Full article

Background: Thermophilic Campylobacter species are among the main culprits behind bacterial gastroenteritis globally and have grown progressively resistant to clinically important antimicrobials. Many studies have been carried out to explore innovative and alternative strategies to control antibiotic-resistant campylobacters in animal reservoirs and human hosts; however, limited studies have been performed to develop efficient control schemes against Campylobacter biofilms. Methods: This study investigated the antimicrobial and antibiofilm activities of some herbal extracts against multidrug-resistant (MDR) Campylobacter species recovered from different sources using phenotypic and molecular techniques. Results: The overall Campylobacter species prevalence was 21.5%, representing 15.25% and 6.25% for C. jejuni and C. coli, respectively. Regarding C. jejuni, the highest resistance rate was observed for amoxicillin–clavulanic acid and colistin (85.25% each), followed by cefotaxime (83.61%) and tetracycline (81.97%), whereas C. coli isolates showed absolute resistance to cefotaxime followed by erythromycin (92%) and colistin (88%). Remarkably, all Campylobacter isolates were MDR with elevated multiple antimicrobial resistance (MAR) indices (0.54–1). The antimicrobial potentials of green tea (Camellia sinensis), rosemary (Rosmarinus officinalis) and ginger (Zingiber officinale) extracts against MDR Campylobacter isolates were assessed by the disk diffusion assay and broth microdilution technique. Green tea extract showed a marked inhibitory effect against tested isolates, exhibiting growth inhibition zone diameters of 8 to 38 mm and a minimum inhibitory concentration (MIC) range of 1.56–3.12 mg/mL, unlike the rosemary and ginger extracts. Our findings reveal a respectable antibiofilm activity (>50% biofilm formation inhibition) of green tea against the preformed biofilms of Campylobacter isolates. Furthermore, real-time quantitative polymerase chain reaction (RT-qPCR) results showed a significant decrease (p < 0.05) in the expression levels of biofilm biosynthesis gene and its regulator (FlaA and LuxS, respectively) in Campylobacter isolates treated with the green tea extract in comparison with untreated ones. Conclusion: This is the first in vitro approach that has documented the inhibitory activity of green tea extract against MDR-biofilm-producing Campylobacter species isolated from different sources. Further in vivo studies in animals’ models should be performed to provide evidence of concept for the implementation of this alternative candidate for the mitigation of MDR Campylobacter infections in the future. Full article

Fungal biota represents important constituents of phyllosphere microorganisms. It is taxonomically highly diverse and influences plant physiology, metabolism and health. Members of the order Diaporthales are distributed worldwide and include devastating plant pathogens as well as endophytes and saprophytes. However, many phyllosphere Diaporthales species remain uncharacterized, with studies examining their diversity needed. Here, we report on the identification of several diaporthalean taxa samples collected from diseased leaves of Cinnamomum camphora (Lauraceae), Castanopsis fordii (Fagaceae) and Schima superba (Theaceae) in Fujian province, China. Based on morphological features coupled to multigene phylogenetic analyses of the internal transcribed spacer (ITS) region, the large subunit of nuclear ribosomal RNA (LSU), the partial beta-tubulin (tub2), histone H3 (his3), DNA-directed RNA polymerase II subunit (rpb2), translation elongation factor 1-α (tef1) and calmodulin (cal) genes, three new species of Diaporthales are introduced, namely, Diaporthe wuyishanensis, Gnomoniopsis wuyishanensis and Paratubakia schimae. This study contributes to our understanding on the biodiversity of diaporthalean fungi that are inhabitants of the phyllosphere of trees native to Asia. Full article

Oil–tea camellia has a long history of cultivation and utilization, with a history of more than 2000 years. In China, it is the main woody oil crop with high economic value and a national resource with unique characteristics. Concurrently, it is also known as one of the four major woody oil crops in the world. However, the genetic background of Camellia drupifera Lour. on Hainan Island in China is still unclear, and there is a great lack of systematic genetic characterization, which seriously hinders the development and utilization of oil–tea camellia germplasm resources and genetic improvement on Hainan Island. To analyze the genetic diversity and kinship between C. drupifera and its related species, this study utilized SSR molecular marker technology to genotype 160 individuals from 23 populations. A total of 137 alleles were amplified from the 14 polymorphic primers, with an average of 9.786. The average number of effective alleles and that of Shannon’s information index for each locus were 1.865 and 0.633, respectively, suggesting that the screened SSR markers presented a moderately high level of polymorphism. Additionally, the mean observed heterozygosity (0.915) was greater than the mean expected heterozygosity (0.450), indicating an excess of heterozygotes in the tested population. The results of the principal component analysis (PCA), molecular variation analysis of variance (AMOVA) and population structure analysis were generally consistent; specifically, there was a high degree of individual heterozygosity within the population, and genetic variation occurred primarily among individuals within the population (90%) but rarely among groups (10%). Additionally, the UPGMA clustering divided the 160 germplasm resources into four major clades, and C. drupifera was principally grouped in two distinct branches; meanwhile, Camellia gauchowensis was also mainly clustered in these two clades. Camellia oleifera individuals were chiefly concentrated in other independent branches. It can be speculated that C. drupifera is genetically close to C. gauchowensis, but genetically distant from C. oleifera. This study can provide the scientific basis for the identification, collection, preservation, evaluation, and innovative utilization of oil–tea camellia. Full article

Sect. Tuberculata, as one of the endemic plant groups in China, belongs to the genus Camellia of the Theaceae family and possesses significant economic and ecological value. Nevertheless, the characteristics of habitat distribution and the major eco-environmental variables affecting its suitability are poorly understood. In this study, using 65 occurrence records, along with 60 environmental factors, historical, present and future suitable habitats were estimated using MaxEnt modeling, and the important environmental variables affecting the geographical distribution of sect. Tuberculata were analyzed. The results indicate that the size of the its potential habitat area in the current climate was 1.05 × 10⁵ km², and the highly suitable habitats were located in Guizhou, central-southern Sichuan, the Wuling Mountains in Chongqing, the Panjiang Basin, and southwestern Hunan. The highest probability of presence for it occurs at mean diurnal range (bio2) ≤ 7.83 °C, basic saturation (s_bs) ≤ 53.36%, temperature annual range (bio7) ≤ 27.49 °C, −7.75 °C < mean temperature of driest quarter (bio9) < 7.75 °C, annual UV-B seasonality (uvb2) ≤ 1.31 × 10⁵ W/m², and mean UV-B of highest month (uvb3) ≤ 5089.61 W/m². In particular, bio2 is its most important environmental factor. During the historical period, the potential habitat area for sect. Tuberculata was severely fragmented; in contrast, the current period has a more concentrated habitat area. In the three future periods, the potential habitat area will change by varying degrees, depending on the aggressiveness of emissions reductions, and the increase in the potential habitat area was the largest in the SSP2.6 (Low-concentration greenhouse gas emissions) scenario. Although the SSP8.5 (High-concentration greenhouse gas emissions) scenario indicated an expansion in its habitat in the short term, its growth and development would be adversely affected in the long term. In the centroid analysis, the centroid of its potential habitat will shift from lower to higher latitudes in the northwest direction. The findings of our study will aid efforts to uncover its originsand geographic differentiation, conservation of unique germplasms, and forestry development and utilization. Full article

Sect. Tuberculata Chang in the genus Camellia (Theaceae Mirb.) is named after the “tubercle-like projections on the surface of the capsule and ovary”. Due to complex morphological variations in these taxon and insufficient field investigations, the interspecies relationships are unclear, the species’ definitions are vague, and the names are confusing. This is not conducive to the conservation and study of these species. Therefore, herein, we systematically explore the taxonomic status of five sect. Tuberculata species using morphological, pollen morphological, and molecular phylogenetic methods. The results showed that (1) the morphological characteristics of the flower, fruit, and leaves of C. anlungensis and C. leyeensis are similar. Furthermore, the pollen characteristics and pollen wall ornamentation show that there is no significant difference between the two species; (2) there are significant differences between C. acutiperulata and C. anlungensis in terms of leaf shape (elliptic vs. obovate), calyx characteristics (sepal apex pointed vs. sepal oblong), and fruit shape (subglobose folds with shallow verruculose vs. flat folds and verruculose protuberances with pronounced internal cleavage); (3) C. pyxidiacea and C. rubituberculata differ in flower color (white or light color vs. red) and fruit verrucae (obviously deeply cleft vs. shallowly uncracked); (4) a phylogenetic tree based on the chloroplast genome shows that C. anlungensis and C. leyeensis form a single clade (BS = 100%, PP = 1.0) and are on a different branch, with C. acutiperulata on clade II (BS = 100%, PP = 1.0), and C. pyxidiacea and C. rubituberculata clustered on different branches of clade I (BS = 99%, PP = 1.00). Considering the above results together, we propose that C. leyeensis should be treated as a homonym of C. anlungensis, and C. acutiperulata, C. pyxidiacea, and C. rubituberculata should be considered as separate species. Clarifying the taxonomic status of these five species not only advances our understanding of the significance and complexity of the systematic classification of the genus Camellia but also has important implications for diversity conservation and population genetics. Full article

Tea (Camellia sinensis) falls into the family Theaceae, is a valuable commercial crop, and tea products made from its buds and young leaves are favored by consumers all over the world. The more common Thea plant is Camellia sinensis (C. sinensis), but its most important relative, Camellia taliensis (C. taliensis), is also utilized by locals in the area of cultivation to manufacture tea. In this investigation, C. taliensis (DL) and C. sinensis (QJZ) were characterized in terms of their agronomic traits, physicochemical indices, metabolomics, and transcriptomics. The leaf area of DL is larger than that of QJZ; the color of DL’s buds and leaves is yellowish-green, while that of QJZ’s is green. DL’s buds and leaves are more densely velvety than those of QJZ. The HPLC results indicated that the physicochemical contents varied considerably between the two samples, with DL having greater concentrations of EGCG and GABA than QJZ, while QJZ had remarkably higher concentrations of C, CA, and EGC than DL. A total of 2269 metabolites and 362,190,414 genes were positively identified, with the number of DAMs and DEGs being 1001 and 34,026, respectively. The flavonoids, phenolic acids, and alkaloid metabolites were dramatically different between the two tea group plants. Bioinformatics profiling revealed that the DAMs and DEGs of the two tea group plants interacted with each other and were involved in metabolic pathways, including “biosynthesis of secondary metabolites”, “biosynthesis of amino acids”, “biosynthesis of cofactors”, “phenylpropanoid biosynthesis”, and “flavonoid biosynthesis”. Overall, these results provide statistical support for germplasm conservation and production for both C. taliensis and C. sinensis. Full article

Camellia drupifera is mainly used in forestry for its high-value industrial products; however, limited information is available on its transcriptome. This study aimed to construct a full-length transcriptome sequence based on the PacBio sequencing platform for various plant parts of C. drupifera, including flower buds, leaves, leaf buds, branches, the pericarp, and seed kernels. The transcriptomes were annotated with 23,207 genes, with 58 subgroups in the GO classification. The KEGG database revealed 10,407 genes involved in the metabolic pathway analysis, with 68,192 coding sequences, 3352 TF families, 48,541 SSRs, 1421 IncRNAs, and 2625 variable shears predicted. The transcriptomes of different parts were analyzed and compared. The majority of differentially expressed genes (DEGs) were found between the pericarp and seed kernels, followed by leaves and the pericarp with 5662 DEGs, and flower buds and leaf buds with 1616 DEGs. GO and KEGG enrichment analyses showed that KEGG differential genes were significant in microbial metabolism, carbon metabolism, and other functions. The data annotation and analysis of the full-length transcriptome and the comparative analysis between different plant parts provided a theoretical basis for studying gene function, metabolic pathway regulation, and gene expression analysis in KEGG. Full article

Plant ecological strategies are essential for assessing habitat stress and disturbance and evaluating community productivity. These strategies provide theoretical frameworks for maintaining the natural state of vegetation and enhancing productivity. The functional traits of leaves reflect a plant’s responses to environmental changes and contribute to understanding ecosystem stability, providing a basis for species diversity maintenance and effective conservation efforts. The Wuyishan National Park, a biodiversity hotspot in China, is a focal point for ecological research. Its evergreen, broad-leaved forest, the zonal vegetation of Mt. Wuyi, underpins plant diversity protection in the region. This study investigates the CSR (competitor, stress-tolerator, ruderal) strategy of 126 species on Wuyi Mountain to elucidate prevalent ecological strategies. The main ecological strategy of plants in the study area is the CS (competitor, stress-tolerator) strategy. The species exhibit nine categories. The most abundant ecological strategy is S/CS (plants from Fagaceae), accounting for 38%, followed by S/CSR at 23% (plants from Theaceae), CS at 20% (plants from Fagaceae and Theaceae), and the remaining strategies collectively at 19%. The different growth habit categories showed variations in the CSR strategies. The trees clustered around a CS median strategy, with no R-selected trees observed. Shrubs and lianas centered around an S/CSR strategy, while grasses and understory shrubs clustered around CS/CSR. Redundancy analysis results indicate that leaf functional traits are primarily influenced by temperature, suggesting that temperature is the key environmental factor driving the differentiation of plant functional traits. This study provides insights into the ecological strategies of plant species in the Mt. Wuyi region, highlighting the importance of considering both biotic and abiotic factors in maintaining biodiversity and ecosystem stability. Full article

Members of the fungal order Diaporthales are sac fungi that include plant pathogens (the notorious chestnut blight fungus), as well as saprobes and endophytes, and are capable of colonizing a wide variety of substrates in different ecosystems, habitats, and hosts worldwide. However, many Diaporthales species remain unidentified, and various inconsistencies within its taxonomic category remain to be resolved. Here, we aimed to identify and classify new species of Diaporthales by using combined morphological and molecular characterization and coupling this information to expand our current phylogenetic understanding of this order. Fungal samples were obtained from dead branches and diseasedleaves of Camellia (Theaceae) and Castanopsis (Fagaceae) in Fujian Province, China. Based on morphological characteristics and molecular phylogenetic analyses derived from the combined nucleotide sequences of loci of the internal transcribed spacer regions with the intervening 5.8S nrRNA gene (ITS), the 28S large subunit of nuclear ribosomal RNA gene (LSU), the translation elongation factor 1-α gene (tef1), the partial beta-tubulin gene (tub2), and partial RNA polymerase II second-largest subunit gene (rpb2), three new species of Diaporthales were identified and characterized. They are as follows: Chrysofolia camelliae sp. nov., Dendrostoma castanopsidis sp. nov., and Pseudoplagiostoma wuyishanense sp. nov. They are described and illustrated. This study extends our understanding of species diversity within the Diaporthales. Full article

Informed species delimitation is crucial in diverse biological fields; however, it can be problematic for species complexes. Showing a peripatric distribution pattern, Stewartia gemmata and S. acutisepala (the S. gemmata complex) provide us with an opportunity to study species boundaries among taxa undergoing nascent speciation. Here, we generated genomic data from representative individuals across the natural distribution ranges of the S. gemmata complex using restriction site-associated DNA sequencing (RAD-seq). Based on the DNA sequence of assembled loci containing 41,436 single-nucleotide polymorphisms (SNPs) and invariant sites, the phylogenetic analysis suggested strong monophyly of both the S. gemmata complex and S. acutisepala, and the latter was nested within the former. Among S. gemmata individuals, the one sampled from Mt. Tianmu (Zhejiang) showed the closest evolutionary affinity with S. acutisepala (which is endemic to southern Zhejiang). Estimated from 2996 high-quality SNPs, the genetic divergence between S. gemmata and S. acutisepala was relatively low (an F_st of 0.073 on a per-site basis). Nevertheless, we observed a proportion of genomic regions showing relatively high genetic differentiation on a windowed basis. Up to 1037 genomic bins showed an F_st value greater than 0.25, accounting for 8.31% of the total. After SNPs subject to linkage disequilibrium were pruned, the principal component analysis (PCA) showed that S. acutisepala diverged from S. gemmata along the first and the second PCs to some extent. By applying phylogenomic analysis, the present study determines that S. acutisepala is a variety of S. gemmata and is diverging from S. gemmata, providing empirical insights into the nascent speciation within a species complex. Full article

Camellia chekiangoleosa is an economically important woody plant from the Genus Camellia in Theaceae, and its seed kernels are rich in edible oils of high health value. Yet, little is known about the molecular regulation of growth and development in C. chekiangoleosa. In this study, we characterized the MYB (Myeloblastosis) gene family that was widely involved in plant development and stress responses, and identified 235 members from the C. chekiangoleosa genome. Based on transcriptomic analysis of multiple tissues, we obtained tissue-specific expression profiles of the MYB genes. We found that 37 MYB genes were highly expressed during seed development, and among them, CcMYB33 (GAMYB) was specifically expressed in the seed coat, suggesting that it may be an important regulator. We cloned full-length sequences of the CcMYB33 gene and further analyzed its sequence characteristics and expression pattern. Our results indicated that CcMYB33 is an R2R3-type MYB transcription factor that is closely related to GAMYB genes of Arabidopsis thaliana. We showed that ectopic expression of CcMYB33 in Arabidopsis lines caused pleiotropical developmental defects, including abnormal leaves, fused stamen, and early flowering, among other things. This work identified important MYB regulators in the regulation of development and growth in C. chekiangoleosa, providing support for further molecular and genetic studies. Full article

Camellia fascicularis belongs to the family Theaceae and is a plant species with extremely small populations. It is also a second-class national protected plant in China. In recent years, the anti-inflammation, antioxidation, and antitumor effects of C. fascicularis polyphenols and flavonoids have been reported. However, changes in the soil chemistry and microbes after artificial cultivation of C. fascicularis have not been well studied. Therefore, three healthy plants from each different artificial planting year’s plot (Age_3, Age_5, and Age_7) were selected, and the chemical properties of the rhizosphere soil and root endophytic microbial communities for different cultivation years of C. fascicularis were studied in Hekou County, China. The accumulation of pathogenic and beneficial microbes in the rhizosphere of C. fascicularis was also discussed. The results show that (1) the alpha diversity in rhizosphere soil was significantly higher than that in roots, and roots recruited more Actinobacteria, which might produce beneficial secondary metabolites for the plant; (2) the total nitrogen in the rhizosphere soil of C. fascicularis cultivated for 7 years was significantly higher than that in the soil cultivated for 3 years; (3) there was no significant difference in the alpha and beta diversity in the rhizosphere soil and root endophytes of C. fascicularis in different cultivation years; (4) there was no difference in the abundance of plant-growth-promoting rhizobacteria (PGPR) in either the rhizosphere soil or roots, but the number of PGPR in roots was higher than that in rhizosphere soil; and (5) the changes in pathogenic fungi and biocontrol fungi in rhizosphere soil were greater than those of endophytic fungi in roots. The results show that there are no significant differences in microbial communities among 3, 5, and 7 years, but the influence of the outside environment on the soil and fungi was greater than that of the roots and bacteria. These results can help us to understand the soil chemical and microbial community changes during the artificial cultivation of C. fascicularis and play an important role in its artificial conservation and breeding, as it is a plant species with extremely small populations. Full article

Camellia luteoflora Li ex Chang is an endangered plant endemic to the East Asian flora with high ornamental value as well as phylogenetic and floristic research value. Predicting the impact of climate change on its distribution and suitable habitat is crucial until scientific conservation measures are implemented. Based on seven environmental variables and 17 occurrence records, this study optimized the MaxEnt model using the kuenm data package to obtain the optimal parameter combinations (RM = 1.3, FC = LPT) and predicted the potential distribution pattern of C. luteoflora in various future periods. The results revealed that the mean diurnal range, temperature annual range, and precipitation of the wettest month were the influential factors determining the distribution pattern of C. luteoflora, contributing 60.2%, 14.4%, and 12.3% of the variability in the data, respectively. Under the current conditions, the area of suitable habitats for C. luteoflora was only about 21.9 × 10⁴ km². Overall, the suitable area around the C. luteoflora distribution points will shrink in a circular pattern in response to future global warming, but some potentially suitable distribution areas will expand and migrate to higher latitudes and the Hengduan Mountains region, representing a survival strategy for coping with climate change. It is hypothesized that the future climate refugia will be the highly suitable area and the Hengduan Mountains region. Furthermore, a retrospective validation method was employed to assess the reliability of the predictions and estimate the model’s predictive performance in the future. This study proposes a survival strategy and adaptation measures for C. luteoflora in response to climate change, and the proposed measures can be generalized for application in conservation planning and restoration processes. We also recommend that future studies incorporate factors such as the anthropogenic disturbances and associated socio-economic activities related to C. luteoflora into the model and to further predict the distribution pattern for C. luteoflora in response to historical climatic changes, tracing the evolutionary history of its population. Full article