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1.
PhytoKeys ; 242: 1-8, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38764934

RESUMEN

In this study, we describe and illustrate a new species, Primulaweiliei L.S.Yang, Z.K.Wu & G.W.Hu, from the Shennongjia Forestry District, Hubei Province in Central China. It is morphologically assigned to Primulasect.Aleuritia based on its dwarf and hairless habit, long petiole, fruits longer than calyx and covered by farina on the scape. This new species is similar to P.gemmifera and P.munroisubsp.yargongensis in the same section, but it can be distinguished by its smaller calyxes, homostylous flowers, corolla tube throat without annular appendage and only 1-2 flowers in each inflorescence. Based on the assessment conducted according to the IUCN Red List criteria, we propose that P.weiliei be classified as a Critically Endangered (CR) species.

2.
Ann Bot ; 133(5-6): 697-710, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38230804

RESUMEN

BACKGROUND AND AIMS: The staghorn fern genus Platycerium is one of the most commonly grown ornamental ferns, and it evolved to occupy a typical pantropical intercontinental disjunction. However, species-level relationships in the genus have not been well resolved, and the spatiotemporal evolutionary history of the genus also needs to be explored. METHODS: Plastomes of all the 18 Platycerium species were newly sequenced. Using plastome data, we reconstructed the phylogenetic relationships among Polypodiaceae members with a focus on Platycerium species, and further conducted molecular dating and biogeographical analyses of the genus. KEY RESULTS: The present analyses yielded a robustly supported phylogenetic hypothesis of Platycerium. Molecular dating results showed that Platycerium split from its sister genus Hovenkampia ~35.2 million years ago (Ma) near the Eocene-Oligocene boundary and began to diverge ~26.3 Ma during the late Oligocene, while multiple speciation events within Platycerium occurred during the middle to late Miocene. Biogeographical analysis suggested that Platycerium originated in tropical Africa and then dispersed eastward to southeast Asia-Australasia and westward to neotropical areas. CONCLUSIONS: Our analyses using a plastid phylogenomic approach improved our understanding of the species-level relationships within Platycerium. The global climate changes of both the Late Oligocene Warming and the cooling following the mid-Miocene Climate Optimum may have promoted the speciation of Platycerium, and transoceanic long-distance dispersal is the most plausible explanation for the pantropical distribution of the genus today. Our study investigating the biogeographical history of Platycerium provides a case study not only for the formation of the pantropical intercontinental disjunction of this fern genus but also the 'out of Africa' origin of plant lineages.


Asunto(s)
Filogenia , Filogeografía , Plastidios , Polypodiaceae , Polypodiaceae/genética , Polypodiaceae/clasificación , Plastidios/genética , Evolución Biológica , África , Helechos/genética , Helechos/clasificación , Evolución Molecular
3.
Plant Mol Biol ; 112(6): 325-340, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37380791

RESUMEN

The contrasting genome size between homosporous and heterosporous plants is fascinating. Different from the heterosporous seed plants and mainly homosporous ferns, the lycophytes are either heterosporous (Isoetales and Selaginellales) or homosporous (Lycopodiales). Many lycophytes are the resource plants of Huperzine A (HupA) which is invaluable for treating Alzheimer's disease. For the seed-free vascular plants, several high-quality genomes of heterosporous Selaginella, homosporous ferns (maidenhair fern, monkey spider tree fern), and heterosporous ferns (Azolla) have been published and provided important insights into the origin and evolution of early land plants. However, the homosporous lycophyte genome has not been decoded. Here, we assembled the first homosporous lycophyte genome and conducted comparative genomic analyses by applying a reformed pipeline for filtering out non-plant sequences. The obtained genome size of Lycopodium clavatum is 2.30 Gb, distinguished in more than 85% repetitive elements of which 62% is long terminal repeat (LTR). This study disclosed a high birth rate and a low death rate of the LTR-RTs in homosporous lycophytes, but the opposite occurs in heterosporous lycophytes. we propose that the recent activity of LTR-RT is responsible for the immense genome size variation between homosporous and heterosporous lycophytes. By combing Ks analysis with a phylogenetic approach, we discovered two whole genome duplications (WGD). Morover, we identified all the five recognized key enzymes for the HupA biosynthetic pathway in the L. clavatum genome, but found this pathway incomplete in other major lineages of land plants. Overall, this study is of great importance for the medicinal utilization of lycophytes and the decoded genome data will be a key cornerstone to elucidate the evolution and biology of early vascular land plants.


Asunto(s)
Embryophyta , Helechos , Filogenia , Tamaño del Genoma , Plantas/genética , Helechos/genética , Embryophyta/genética , Secuencias Repetidas Terminales , Evolución Molecular
4.
Front Plant Sci ; 14: 1183653, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37346120

RESUMEN

Germplasm resources are the source of herbal medicine production. The cultivation of superior germplasm resources helps to resolve the conflict between long-term population persistence and growing market demand by consistently producing materials with high quality. The fern species Cibotium barometz is the original plant of cibotii rhizoma ("Gouji"), a traditional Chinese medicine used in the therapy of pain, weakness, and numbness in the lower extremities. Long-history medicinal use has caused serious wild population decline in China. Without sufficient understanding of the species and lineage diversity of Cibotium, it is difficult to propose a targeted conservation scheme at present, let alone select high-quality germplasm resources. In order to fill such a knowledge gap, this study sampled C. barometz and relative species throughout their distribution in China, performed genome skimming to obtain plastome data, and conducted phylogenomic analyses. We constructed a well-supported plastome phylogeny of Chinese Cibotium, which showed that three species with significant genetic differences are distributed in China, namely C. barometz, C. cumingii, and C. sino-burmaense sp. nov., a cryptic species endemic to NW Yunnan and adjacent regions of NE Myanmar. Moreover, our results revealed two differentiated lineages of C. barometz distributed on the east and west sides of a classic phylogeographic boundary that was probably shaped by monsoons and landforms. We also evaluated the resolution of nine traditional barcode loci and designed five new DNA barcodes based on the plastome sequence that can distinguish all these species and lineages of Chinese Cibotium accurately. These novel findings on a genetic basis will guide conservation planners and medicinal plant breeders to build systematic conservation plans and exploit the germplasm resources of Cibotium in China.

5.
Mol Phylogenet Evol ; 179: 107673, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36528332

RESUMEN

Spikemoss (Selaginellaceae) is one of the basal lineages of vascular plants. This family has a single genus Selaginella which consists of about 750 extant species. The phylogeny of Selaginellaceae has been extensively studied mainly based on plastid DNA and a few nuclear sequences. However, the placement of the enigmatic sinensis group is a long-term controversy because of the long branch in the plastid DNA phylogeny. The sanguinolenta group is also a phylogenetically problematic clade owing to two alternative positions resulted from different datasets. Here, we newly sequenced 34 mitochondrial genomes (mitogenomes) of individuals representing all seven subgenera and major clades in Selaginellaceae. We assembled the draft mitogenomes and annotated the genes and performed phylogenetic analyses based on the shared 17 mitochondrial genes. Our major results include: (1) all the assembled mitogenomes have complicated structures, unparalleled high GC content and a small gene content set, and the positive correlations among GC content, substitution rates and the number of RNA editing sites hold; (2) the sinensis group was well supported as a member of subg. Stachygynandrum; (3) the sanguinolenta group was strongly resolved as sister to all other Selaginella species except for subg. Selaginella. This study demonstrates the potential of mitogenome data in providing novel insights into phylogenetically recalcitrant problems.


Asunto(s)
Genoma Mitocondrial , Selaginellaceae , Humanos , Filogenia , Selaginellaceae/genética , Secuencia de Bases , Plastidios/genética
6.
Mol Phylogenet Evol ; 180: 107672, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36539018

RESUMEN

As an endemic Chinese genus, Sinopteris C. Chr. & Ching was once considered an early diverged taxon of cheilanthoid ferns, and its taxonomic status has long been controversial. In this study, eight datasets spanning the complete chloroplast genomes and three nuclear genes were used to reconstruct the phylogeny of Sinopteris and its relatives. In addition, combining morphological analyses, divergence time estimation, and ancestral trait reconstruction, the origin and evolutionary history of Sinopteris were comprehensively discussed. Based on the complete chloroplast genome dataset, our analyses yielded a phylogram with all clades strongly supported (ML-BS = 100, BI-PP = 1.0), and the topology was almost identical to that based on the concatenated sequences of nrDNA, CRY2, and IBR3. Two species of Sinopteris were united and sister to Aleuritopteris niphobola (C. Chr.) Ching. They constituted a stable monophyletic group embedded in Aleuritopteris Fée. This was also consistent with the results of morphological analyses. Divergence time estimation indicated that the clade of Aleuritopteris and Sinopteris originated in the early Miocene (ca. 16.80 Ma) and experienced two rapid diversifications, which could coincide with environmental heterogeneity caused by the progressive uplift of the Himalayas and the intense uplift of the Hengduan Mountains. Sinopteris originated in the late Miocene (ca. 6.96 Ma), accompanied by the sharp intensifications of Asian Monsoon, and began to diversify at 2.34 Ma, following the intense uplift of the Hengduan Mountains. Ancestral character reconstruction showed that monangial sori and subsessile sporangia were clearly late derived states rather than early diverged states. Both the molecular phylogenetic and morphological analyses support the inclusion of Sinopteris in Aleuritopteris.


Asunto(s)
Helechos , Genoma del Cloroplasto , Pteridaceae , Filogenia , Evolución Biológica
7.
Front Psychol ; 13: 1007190, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36389527

RESUMEN

Many scholars have focused on understanding ways of how to suppress knowledge hiding by employees. Existing studies have demonstrated that mindfulness could effectively inhibit employees' knowledge hiding. This study aims to investigate the impact of leader-subordinate mindfulness congruence on subordinate knowledge hiding and its internal mechanisms. Based on the role theory, we collected 169 leadership data and 368 employee data at three time-points through collecting questionnaire of matching leaders and subordinates. In addition, we used polynomial regression and response surface analysis to validate our research hypotheses. The results demonstrated that: (i) Compared with the "high leader-high subordinate" mindfulness congruence condition, subordinates in the "low leader-low subordinate" mindfulness congruence condition were more likely to exhibit knowledge hiding. (ii) Compared with the "low leader-high subordinate" mindfulness incongruence, subordinates under the "high leader-low subordinate" mindfulness incongruence are more likely to exhibit knowledge hiding. (iii) The more incongruent the mindfulness between the leader and the subordinate is, the more likely an employee is to exhibit knowledge hiding. (iv) Emotional exhaustion mediated the correlation between leader-subordinate mindfulness congruence and knowledge hiding. (v) When the gender of the leader and the subordinate is different, the impact of mindfulness congruence on the inhibition of emotional exhaustion is stronger. This study provides a new perspective for researching the impact of mindfulness on individual behavior and provides a new idea for the research related to inhibiting knowledge hiding.

8.
Genes (Basel) ; 13(7)2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35886063

RESUMEN

Although extant lycophytes represent the most ancient surviving lineage of early vascular plants, their plastomic diversity has long been neglected. The ancient evolutionary history and distinct genetic diversity patterns of the three lycophyte families, each with its own characteristics, provide an ideal opportunity to investigate the interfamilial relationships of lycophytes and their associated patterns of evolution. To compensate for the lack of data on Lycopodiaceae, we sequenced and assembled 14 new plastid genomes (plastomes). Combined with other lycophyte plastomes available online, we reconstructed the phylogenetic relationships of the extant lycophytes based on 93 plastomes. We analyzed, traced, and compared the plastomic diversity and divergence of the three lycophyte families (Isoëtaceae, Lycopodiaceae, and Selaginellaceae) in terms of plastomic diversity by comparing their plastome sizes, GC contents, substitution rates, structural rearrangements, divergence times, ancestral states, RNA editings, and gene losses. Comparative analysis of plastid phylogenomics and plastomic diversity of three lycophyte families will set a foundation for further studies in biology and evolution in lycophytes and therefore in vascular plants.


Asunto(s)
Genoma de Plastidios , Tracheophyta , Composición de Base , Evolución Molecular , Humanos , Filogenia , Plastidios/genética , Tracheophyta/genética
9.
Plant J ; 111(3): 768-784, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35648423

RESUMEN

Two factors are proposed to account for the unusual features of organellar genomes: the disruptions of organelle-targeted DNA replication, repair, and recombination (DNA-RRR) systems in the nuclear genome and repetitive elements in organellar genomes. Little is known about how these factors affect organellar genome evolution. The deep-branching vascular plant family Selaginellaceae is known to have a deficient DNA-RRR system and convergently evolved organellar genomes. However, we found that the plastid genome (plastome) of Selaginella sinensis has extremely accelerated substitution rates, a low GC content, pervasive repeat elements, a dynamic network structure, and it lacks direct or inverted repeats. Unexpectedly, its organelle DNA-RRR system is short of a plastid-targeted Recombinase A1 (RecA1) and a mitochondrion-targeted RecA3, in line with other explored Selaginella species. The plastome contains a large collection of short- and medium-sized repeats. Given the absence of RecA1 surveillance, we propose that these repeats trigger illegitimate recombination, accelerated mutation rates, and structural instability. The correlations between repeat quantity and architectural complexity in the Selaginella plastomes support these conclusions. We, therefore, hypothesize that the interplay of the deficient DNA-RRR system and the high repeat content has led to the extraordinary divergence of the S. sinensis plastome. Our study not only sheds new light on the mechanism of plastome divergence by emphasizing the power of cytonuclear integration, but it also reconciles the longstanding contradiction on the effects of DNA-RRR system disruption on genome structure evolution.


Asunto(s)
Genoma de Plastidios , Selaginellaceae , ADN , Evolución Molecular , Genoma de Plastidios/genética , Filogenia , Selaginellaceae/genética
10.
Mol Phylogenet Evol ; 173: 107507, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35589053

RESUMEN

Different from the generally conserved plastomes (plastid genomes) of most land plants, the Selaginellaceae plastomes exhibit dynamic structure, high GC content and high substitution rates. Previous plastome analyses identified strong conflict on several clades in Selaginella, however the factors causing the conflictions and the impact on the phylogenetic inference have not been sufficiently investigated. Here, we dissect the distribution of phylogenetic signals and conflicts in Selaginella sanguinolenta group, the plastome of which is DR (direct repeats) structure and with genome-wide RNA editing. We analyzed the data sets including 22 plastomes representing all species of the S. sanguinolenta group, covering the entire geographical distribution from the Himalayas to Siberia and the Russian Far East regions. We recovered four different topologies by applying multispecies coalescent (ASTRAL) and concatenation methods (IQ-TREE and RAxML) on four data sets of PC (protein-coding genes), NC (non-coding sequences), PCN (the concatenated PC and NC), and RC (predicted RNA editing sites "C" were corrected by "T"), respectively. Six monophyletic clades, S. nummularifolia clade, S. rossii clade, S. sajanensis clade, S. sanguinolenta I clade, S. sanguinolenta II clade, and S. sanguinolenta III clade, were consistently resolved and supported by the characteristics of GC content, RNA editing frequency, and gene content. However, the relationships among these clades varied across the four topologies. To explore the underlying causes of the uncertainty, we compared the phylogenetic signals of the four topologies. We identified that the sequence types (coding versus non-coding), outlier genes (genes with extremely high |ΔGLS| values), and C-to-U RNA editing frequency in the protein-coding genes were responsible for the unstable phylogenomic relationship. We further revealed a significant positive correlation between the |ΔGLS| values and the variation coefficient of the RNA editing number. Our results demonstrated that the coalescent method performed better than the concatenation method in overcoming the problems caused by outlier genes and extreme RNA editing events. Our study particularly focused on the importance of exploring the plastid phylogenomic conflicts and suggested conducting concatenated analyses cautiously when adopting organelle genome data.


Asunto(s)
Genoma de Plastidios , Selaginellaceae , Evolución Molecular , Filogenia , Plastidios/genética , Edición de ARN , Selaginellaceae/genética
11.
Plant Divers ; 44(2): 141-152, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35505989

RESUMEN

Ferns and lycophytes have remarkably large genomes. However, little is known about how their genome size evolved in fern lineages. To explore the origins and evolution of chromosome numbers and genome size in ferns, we used flow cytometry to measure the genomes of 240 species (255 samples) of extant ferns and lycophytes comprising 27 families and 72 genera, of which 228 species (242 samples) represent new reports. We analyzed correlations among genome size, spore size, chromosomal features, phylogeny, and habitat type preference within a phylogenetic framework. We also applied ANOVA and multinomial logistic regression analysis to preference of habitat type and genome size. Using the phylogeny, we conducted ancestral character reconstruction for habitat types and tested whether genome size changes simultaneously with shifts in habitat preference. We found that 2C values had weak phylogenetic signal, whereas the base number of chromosomes (x) had a strong phylogenetic signal. Furthermore, our analyses revealed a positive correlation between genome size and chromosome traits, indicating that the base number of chromosomes (x), chromosome size, and polyploidization may be primary contributors to genome expansion in ferns and lycophytes. Genome sizes in different habitat types varied significantly and were significantly correlated with habitat types; specifically, multinomial logistic regression indicated that species with larger 2C values were more likely to be epiphytes. Terrestrial habitat is inferred to be ancestral for both extant ferns and lycophytes, whereas transitions to other habitat types occurred as the major clades emerged. Shifts in habitat types appear be followed by periods of genomic stability. Based on these results, we inferred that habitat type changes and multiple whole-genome duplications have contributed to the formation of large genomes of ferns and their allies during their evolutionary history.

12.
Mol Ecol ; 31(9): 2679-2697, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35253951

RESUMEN

The formation of spatial genetic structure with the presence of extensive gene flow, an evolutionary force which is generally expected to eliminate population-specific variation and maintain genetic homogeneity, remains poorly understood. Homosporous ferns, which spread by spores through wind and possess long distance dispersal capacity, provide an ideal system to investigate such a process. Here, using a homoploid fern lineage, the Athyrium sinense complex, we used reduced-representation genomic data to examine spatial genetic structure and explored potential driving forces including geographical distance, environment, climatic history and external dispersal constraints. Our findings showed a clear north-south divergence at the genetic, morphological and ecological levels between both sides of 35°N in East Asia. Fluctuant and heterogeneous climatic condition was demonstrated to play a crucial role during the formation of the divergence. Our results suggested that this lineage was able to migrate southward and colonize new habitat as a result of the Quaternary climatic fluctuation. Furthermore, the present genetic structure is attributed to adaptation to heterogeneous environments, especially temperature difference. In addition to ecological adaptation, we found clues showing that canopy density, wind direction as well as habitat continuity were all likely to constrain the effect of gene flow. These results demonstrated a diversification process without ploidy changes in ferns providing new insights for our present knowledge on ferns' spatio-temporal evolutionary pattern. In particular, our study highlights the influence of environmental heterogeneity in driving genetic divergence against strong dispersal capacity.


Asunto(s)
Helechos , Aclimatación , Ecosistema , Helechos/genética , Estructuras Genéticas , Variación Genética/genética
13.
Nat Plants ; 8(2): 125-135, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35102275

RESUMEN

The rapid Cretaceous diversification of flowering plants remains Darwin's 'abominable mystery' despite numerous fossil flowers discovered in recent years. Wildfires were frequent in the Cretaceous and many such early flower fossils are represented by charcoalified fragments, lacking complete delicate structures and surface textures, making their similarity to living forms difficult to discern. Furthermore, scarcity of information about the ecology of early angiosperms makes it difficult to test hypotheses about the drivers of their diversification, including the role of fire in shaping flowering plant evolution. We report the discovery of two exquisitely preserved fossil flower species, one identical to the inflorescences of the extant crown-eudicot genus Phylica and the other recovered as a sister group to Phylica, both preserved as inclusions together with burned plant remains in Cretaceous amber from northern Myanmar (~99 million years ago). These specialized flower species, named Phylica piloburmensis sp. nov. and Eophylica priscastellata gen. et sp. nov., exhibit traits identical to those of modern taxa in fire-prone ecosystems such as the fynbos of South Africa, and provide evidence of fire adaptation in angiosperms.


Asunto(s)
Ámbar , Rhamnaceae , Ecosistema , Fósiles , Mianmar
14.
Cladistics ; 37(6): 717-727, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34841589

RESUMEN

The polygrammoids (Polypodiaceae) are the most species-rich and diversified epiphytic fern lineages, and hold an important role to understand the deep diverging events and rapid adaptation to changing environments in the plant tree of life. Despite progress in the phylogeny of this group of ferns in previous multilocus phylogenetic studies, uncertainty remains especially in backbone relationships among closely related clades, and the phylogenetic placement of recalcitrant species or lineages. Here, we investigated the deep phylogenetic relationships within Polypodiaceae by sampling all major lineages and using 81 plastid genomes (plastomes), of which 70 plastomes were newly sequenced with high-throughput sequencing technology. Based on parsimony, maximum-likelihood, Bayesian and multispecies coalescent analyses of genome skimming data, we achieved a better resolution of the backbone phylogeny of Polypodiaceae. Using simulated data matrices, we detected that potential phylogenetic artefacts, such as long-branch attraction and insufficient taxonomic sampling, may have a confounding impact on the incongruence of phylogenetic inferences. Furthermore, our phylogenetic analyses offer greater resolution than previous multilocus studies, providing a robust framework for future phylogenetic implications on the subfamilial taxonomy of Polypodiaceae. Our phylogenomic study not only demonstrates the advantage of a character-rich plastome dataset for resolving the recalcitrant lineages that have undergone rapid radiation, but also sheds new light on integrative explorations understanding the evolutionary history of large fern groups in the genomic era.


Asunto(s)
Plastidios/genética , Polypodiaceae/genética , Genoma de Plastidios , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Plastidios/clasificación , Polypodiaceae/clasificación
15.
PLoS One ; 16(9): e0256837, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34570772

RESUMEN

Chinese e-commerce companies are in the ascendant into the overseas market, while still lack adequate academic attention. Adopting case study and public policy approaches, this article applies the symbiosis theory, based on the fundamentals of the development data of Chinese e-commerce companies in the Indonesia market, to construct an evaluation model and proposes a strategic orientation to reaching an embedded survival and further development. Through understanding the structural characteristics and developing status of different types of Chinese e-commerce companies going overseas, a detailed investigation to the Chinese e-commerce companies investing in Indonesia has been conducted. Findings show that the production capacity cooperation stage of the two countries has a trend of asymmetric symbiosis gradually developing towards symmetric symbiosis. To promote a continuous economic cooperation between China and Indonesia, this article proposes that the national-level collaboration policies, cross-border e-commerce value chain, as well as organizational-level coordination are the key sectors for reaching the vision of symmetric symbiosis between the two countries. Sectors in infrastructure, trade, capital, and people's mindset intimacy also contribute to construct a symbiosis mechanism for capacity cooperation between the two nations.


Asunto(s)
Comercio/estadística & datos numéricos , Correo Electrónico/economía , Cooperación Internacional , Modelos Econométricos , China , Humanos , Indonesia , Inversiones en Salud/estadística & datos numéricos
16.
Front Psychol ; 12: 634133, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34366961

RESUMEN

Time pressure (TP) is the most common kind of pressure faced by R&D teams. How to improve team innovation performance (TIP) when time resources are insufficient has been a concern of practitioners and scholars. The purpose of this paper is to put forward some suggestions to solve that time dilemma. We conducted a survey based on a sample of 163 teams. In the first-stage survey (time 1), we measured the team temporal leadership (TTL) and TP. In the second-stage survey (time 2), we measured team learning behavior (TLB). TIP was measured in the third-wave survey (time 3). The results are as follows: (i) TTL has a significant positive impact on the TLB and TIP; (ii) TLB plays a mediating role in the relationship between TTL and TIP; and (iii) TP can positively moderate the relationship between TTL and TLB, that is, the promoting effect of TTL on TLB is more pronounced under the higher level of TP. These findings reveal the influence mechanism of TTL on TIP from the perspective of TLB and TP.

18.
Mol Ecol Resour ; 21(6): 2177-2186, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33934526

RESUMEN

Plastid genomes play an important role in genomics and evolutionary biology. Next-generation sequencing has revolutionized plastid genomic data acquisition to the point that genome assembly has become a bottleneck for widespread utilization of plastid genome data. To solve this problem, we developed an open-source, cross-platform tool known as, NOVOWrap, which includes both command-line and graphical interfaces for automatically assembling plastid genomes on personal computers. With minimal inputs, settings, and user intervention, NOVOWrap can automatically assemble plastid genomes, validate results and standardize the structure using affordable computer resources. The performance of this software has been successfully benchmarked against the plastid genomes of 11 species belonging to lycopods, gymnosperms, and angiosperms. By liberating researchers from laborious and cumbersome computer manipulations and create reliable and standardized genomic data, NOVOWrap is expected to accelerate plastid genome assembly, ease the process of data exchange, and contribute to downstream analysis.


Asunto(s)
Genoma de Plastidios , Plastidios , Programas Informáticos , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Plastidios/genética , Estándares de Referencia
19.
Mol Phylogenet Evol ; 161: 107176, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33866009

RESUMEN

The establishment of a segregate lepisoroid fern genus Ellipinema was mainly to accommodate the isolated position of Lepisorus jakonensis (Polypodiaceae) recovered in plastid gene tree. Using newly obtained nuclear data, we recovered that Ellipinema and allied genera, such as Lepidomicrosorium, Lemmaphyllum, Neolepisorus, Paragramma, Tricholepidium and Weatherbya are deeply nested within Lepisorus. The nuclear phylogeny showing incongruent phylogenetic placement in comparison with plastid results perhaps indicated ancient hybridization events. The diagnostic morphology characterizing Ellipinema - elliptic scale-like paraphyses, which is shared by all the taxa of sect. Lepisorus and sect. Hymenophyton - falls within the range of continuous variation in the type species Ellipinema jakonense (=Lepisorus jakonensis). Our study, which integrated molecular and morphological data, demonstrates that the segregation of Ellipinema and ×Ellipisorus (= ×Lepinema Li Bing Zhang & Liang Zhang, nom. illeg.) from Lepisorus should be rejected.


Asunto(s)
Filogenia , Polypodiaceae/clasificación , Polypodiaceae/genética , ADN de Plantas/genética , Plastidios/genética , Polypodiaceae/citología
20.
PhytoKeys ; 174: 95-106, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33776525

RESUMEN

Hoya pyrifolia, a new species of Apocynaceae from Yunnan Province, China, is described and illustrated. Results from phylogenetic analyses, based on combined DNA fragments of the nuclear ribosomal external transcribed spacer (ETS), intergeneric transcribed spacer (ITS) and three plastid DNA fragments (matK, psbA-trnH and trnT-trnL), showed that the new species was nested within a clade, including Hoya species distributed in the subtropical foothills of the Himalayas and the Tibet-Sichuan Plateau. Morphologically, the new species can be distinguished from its close relatives by its pyriform and slightly pubescent leaves, as well as the 4-flowered inflorescences.

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