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The inflorescences of Solanaceae are unique and complex, which has led to long-standing disputes over floral symmetry mainly due to different interpretations of the cyme-like inflorescence structure. The main disagreements have been over how the phyllomes associated with the flower were arranged relative to the inflorescence axis especially during early flower initiation.Here we investigated the evolution of inflorescences in Solanaceae by analyzing inflorescence structure in the context of phylogeny using ancestral state reconstruction (ASR) to determine the evolutionary transitions between loosely arranged and tightly clustered inflorescences and between monochasial-like and dichasial-like cymes. We also reconstructed two- and three-dimensional models for 12 solanaceous species that represent both inflorescence and phylogenetic diversity in the family.Our results indicate that the most recent common ancestor of Solanaceae had a loosely arranged and monochasial-like cyme, while tightly clustered inflorescences and dichasial-like cymes were derived. Compared to the known process of scorpioid cyme evolution, Solanaceae achieved their scorpioid cyme-like inflorescences through a previously undescribed way. Along the pedicel, the two flower-preceding prophylls are not in the typical transverse position of dicotyledonous plants; they frequently have axillary buds, and the main inflorescence axis continues in a sympodial fashion. As a result, the plane of symmetry of the flower is 36° from the median, and the inflorescence axis and the two flower-preceding prophylls are symmetrically located along that plane.A better understanding of the morphological evolution of solanaceous inflorescence structure helped clarify the floral symmetry of Solanaceae.

This letter proposes a dynamic joint scheduling for the ultra-reliable low-latency communication (URLLC) and enhanced mobile broadband (eMBB) traffic at a sub-frame level with a queuing mechanism, which monitors and controls the latency of each URLLC packet in real time to ensure its strict requirements. We analytically derive the outage probability (i.e., the probability of any URLLC packet drop over all transmission channels) and URLLC expected throughput in addition to the expected value of served URLLC packets. Then, a stochastic optimization problem is formulated to maximize the total throughput for the eMBB services, constraining the URLLC outage probability. Numerical results confirm effectiveness of our queuing policy to significantly reduce the URLLC loss rate while ensuring that the total eMBB throughput is not affected.

As an important service for 5G communications, ultra-reliable low-latency communications (URLLC) support emerging mission-critical applications, such as factory automation and autonomous driving. For such applications, the probability of failing to successfully transmit URLLC packets should be below a certain threshold. However, in the case of limited knowledge of the channel distribution, achieving such a reliability target requires precise channel modeling. In this paper, we study applying a non-parametric statistical learning approach (i.e. kernel density estimation (KDE)) to estimate the information of the wireless transmission environment (i.e. the probability density function of the channel distribution). Based on the estimated cumulative distribution function, a transmission rate control technique has been developed and the corresponding reliability has been investigated using two measures representing the average performance and the confidence level. Moreover, this paper compares the performance of KDE and traditional empirical estimation scheme. The results show that KDE achieves a high level of confidence in guaranteeing the reliability constraint despite of the limited number of training data when choosing a suitable kernel bandwidth.

The purposeful exploration of efficient methodologies towards synthesizing phase-pure multi-compositional nanostructures is an everlasting topic for material scientists. In this work, we first devise a smart strategy to fabricate high-purity Li2FeSiO4 nanofibers (LFSNFs) with a P21/n structure via controllable electrospinning and subsequent calcination in air and N2 atmospheres. Systematic physicochemical characterization confirms the significant roles of the regulation of polyvinyl pyrrolidone (PVP) content via pretreatment in air, and concentrations of inorganic salts in the formation of one-dimensional LFSNFs. Specifically, the excess PVP-derived carbon content will result in the carbon-thermal reduction of high-valence Fe species, and high concentrations of precursors will increase the diameter of the nanofibers, and even induce the conversion from nanofibers to nanobelts. Finally, the optimum synthetic parameters are convincingly proposed. More significantly, we strongly believe that the unusual formation mechanism of the LFSNFs will have enormous potential in enriching synthetic methods of polyoxyanion nano-architectures.

To satisfy the practical applications of Na-ion batteries (NIBs), the pursuit of high-rate cathodes, especially with superior wide-temperature-tolerant sodium storage capability is of vital importance. Herein, we first comparatively investigated the sodium-storage performances of NaCrO2 nanowires (NCO NWs) and conventional bulk NaCrO2 (BNCO) cathodes within the wide operating temperature range from −15 to 55 °C both in half and pouch-type cells. The investigation comprehensively demonstrated that the one-dimensional (1D) nano-structured NCO NWs exhibited better Na+-storage properties in terms of reversible capacity, rate behavior and cycling stability, compared to their counterpart BNCO cathode over the whole testing temperature range. And intrinsic reasons for the enhanced electrochemical performance of the 1D NCO cathode were elucidated in-depth with electrochemical and physicochemical characterization. The NCO NW-based pouch-type devices delivered superior temperature-dependent discharge capacities of ∼79.5 (−15 °C), ∼104.8 (25 °C) and ∼103.6 (55 °C) mA h g−1, along with remarkable capacity retentions of ∼78.3% (−15 °C) after 100 cycles, and ∼92.7% (25 °C)/∼82.8% (55 °C) after 200 cycles at 2C rate. Our contribution here will stimulate large-scale applications of the selected NCO NWs for commercial NIBs to some extent, and provide significant guidance for fine exploration of other NW-based cathodes for wide-temperature-operating NIBs.

PREMISE OF THE STUDY Observations of floral ontogeny indicated that floral organ initiation in pentapetalous flowers most commonly results in a median-abaxial (MAB) petal during early development, a median-adaxial (MAD) petal being less common. Such different patterns of floral organ initiation might be linked with different morphologies of floral zygomorphy that have evolved in Asteridae. Here, we provide the first study of zygomorphy in pentapetalous angiosperms placed in a phylogenetic framework, the goal being to find if the different patterns of floral organ initiation are connected with particular patterns of zygomorphy. METHODS We analyzed patterns of floral organ initiation and displays of zygomorphy, extracted from floral diagrams representing 405 taxa in 330 genera, covering 83% of orders (30 out of 36) and 37% of families (116 out of 313) in core eudicots in the context of a phylogeny using ancestral state reconstructions. KEY RESULTS The MAB petal initiation is the ancestral state of the pattern of floral organ initiation in pentapetalous angiosperms. Taxa with MAD petal initiation represent ∼30 independent origins from the ancestral MAB initiation. There are distinct developmental processes that give rise to zygomorphy in different lineages of pentapetalous angiosperms, closely related lineages being likely to share similar developmental processes. CONCLUSIONS We have demonstrated that development indeed constrains the processes that give rise to floral zygomorphy, while phylogenetic distance allows relaxation of these constraints, which provides novel insights on the role that development plays in the evolution of floral zygomorphy.

In Solanaceae, a group dominated by actinomorphic-flowered species, floral zygomorphy is frequently observed among the early-branching clades. Morphological studies indicated that a zygomorphic androecium is much more common than a zygomorphic corolla in the family. Ontogenic studies suggested the evolution of floral zygomorphy in these two whorls is independent. Here, we have examined the evolution of floral symmetry in the androecium and corolla in Solanaceae. The character states of floral symmetry were assembled for androecium and corolla separately, and ancestral state reconstructions were carried out at both the genus and species levels for Solanaceae and its outgroups. Correlation tests were performed to determine whether the presence of floral zygomorphy in the androecium and corolla is correlated. The ancestral state reconstructions suggest the flower of the most recent common ancestor of Solanaceae is likely zygomorphic in the androecium but actinomorphic in the corolla. Multiple losses and gains of floral zygomorphy in androecium and corolla explain the existing pattern of floral symmetry in Solanaceae. A significant positive correlation between the possession of floral zygomorphy in the androecium and corolla of Solanaceae was detected. Floral zygomorphy likely has evolved in androecium and corolla along separate evolutionary trajectories, and zygomorphy in the androecium may be a precursor for the many gains of zygomorphy in the corolla in Solanaceae.

Angiosperms evolved a great diversity of ways to display their flowers for reproductive success by variation in floral color, size, shape, scent, arrangements, and flowering time. The various innovations in floral forms and the aggregation of flowers into different kinds of inflorescences can drive new ecological adaptations, speciation, and angiosperm diversification. Evolutionary developmental biology (evo-devo) seeks to uncover the developmental and genetic basis underlying morphological diversification. Advances in the developmental genetics of floral display have provided a foundation for insights into the genetic basis of floral and inflorescence evolution. A number of regulatory genes controlling floral and inflorescence development have been identified in model plants (e.g., Arabidopsis thaliana, Antirrhinum majus) using forward genetics and conserved functions of many of these genes across diverse non-model species have been revealed by reverse genetics. Gene-regulatory networks that mediated the developmental progresses of floral and inflorescence development have also been established in some plant species. Meanwhile, phylogeny-based comparative analysis of morphological and genetic character has enabled the identification of key evolutionary events that lead to morphological complexity and diversification. Here we review the recent progress on evo-devo studies of floral display including floral symmetry, petal fusion, floral color, floral scent, and inflorescences. We also review the molecular genetic approaches applied to plant evo-devo studies and highlight the future directions of evo-devo.

Conductive metal-organic frameworks (MOFs), as a newly emerging multifunctional material, hold enormous promise in electrochemical energy-storage systems owing to their merits including good electronic conductivity, large surface area, appropriate pore structure, and environmental friendliness. In this contribution, a scalable solvothermal strategy was devised for the bottom-up fabrication of 1D Cu-based conductive MOF, that is, Cu3 (2,3,6,7,10,11-hexahydroxytriphenylene)2 (Cu-CAT) nanowires (NWs), which were further utilized as a competitive anode for lithium-ion batteries (LIBs). The intrinsic Li storage mechanism of the Cu-CAT electrode was also explored. Benefiting from its structural virtues, the resultant 1D Cu-CAT NWs were endowed with superb Li+ diffusion coefficients and electrochemical conductivities and exhibited remarkably high-rate reversible capacities of approximately 631 mAh g-1 at 0.2 A g-1 and even approximately 381 mAh g-1 at 2 A g-1 , along with striking capacity retention of 81 % after 500 cycles at 0.5 A g-1 . In addition, a Cu-CAT NWs-based full cell assembled with LiNi0.8 Co0.1 Mn0.1 O2 as the cathode displayed a large energy density of approximately 275 Wh kg-1 as well as excellent cycling behavior. These results manifest the promising application of 1D conductive Cu-CAT NWs in advanced LIBs and even other potential versatile energy-related fields.

Premise of research. The primarily Neotropical Malpighiaceae exhibit an elegant suite of floral morphological characteristics associated with a specialized mutualism with oil bee pollinators, including bilaterally symmetrical flowers and paired oil glands on the calyx. One clade within the family, Hiptage Gaertn., has migrated to the paleotropics and lost its association with oil bees. Corresponding to this transition, some members of Hiptage have evolved a highly elaborate zygomorphic corolla with strongly reflexed petals and striking dorsoventral heteranthery. Previously, we demonstrated that expression of CYCLOIDEA2-like (CYC2-like) genes is correlated with the evolution of floral symmetry in Malpighiaceae. Here, we examine CYC2 expression in relation to the evolution of elaborate floral zygomorphy in Hiptage benghalensis.Methodology. CYC2-like genes were cloned from H. benghalensis. The spatial pattern of CYC2 expression was examined with quantitative reverse-transcription PCR on the dissected floral ...

Recently, the Ni-rich LiNi0·8Co0·1Mn0·1O2 (NCM811) cathode with high-energy applications has received tremendous interest for Li-ion batteries (LIBs). But it still suffers from serious capacity degradation upon cycling owing to the involved sur-/interface issues. In the work, we first propose an efficient surface modification strategy to in-situ fabricate the NCM811 coated with solid electrolyte Li3PO4, and systematically investigate the effect of Li3PO4 nano coating layer on electrochemical stability of the NCM811 for LIBs as competitive cathodes. It is the smart surface coating of Li+ conductive Li3PO4 that lowers the sensitivity to H2O and CO2, relieves the evolution of strain-induced intergranular micro-cracks, slows the HF corrosion, and retains the fast Li+ diffusion coefficients with appropriate coating content. The optimized NCM811@Li3PO4 cathode yields the remarkable electrochemical Li-storage properties in terms of reversible capacities, capacity retention and rate behaviors. More competitively, the NCM811@Li3PO4 based pouch-type devices deliver a cell-level energy density of ∼304.6 Wh kg−1, along with a capacity retention of 89.6% over 250 cycles at 1.0 C. The appealing features highlight promising application of the resultant NCM811@Li3PO4 cathodes in next-generation LIBs.

Developmental genetic studies of Antirrhinum majus demonstrated that two transcription factors from the MYB gene family, RADIALIS (RAD) and DIVIRICATA (DIV), interact through antagonism to regulate floral dorsoventral asymmetry. Interestingly, similar antagonistic interaction found among proteins of FSM1 (RAD-like) and MYBI (DIV-like) in Solanum lycopersicum is involved in fruit development. Here, we report the reconstruction of the phylogeny of I-box-like and R-R-type clades, where RAD- and DIV-like genes belong, respectively. We also examined the homology of these antagonistic MYB proteins using these phylogenies. The results show that there are likely three paralogs of RAD-/I-box-like genes, RAD1, RAD2, and RAD3, which originated in the common ancestor of the core eudicots. In contrast, R-R-type sequences fall into two major clades, RR1 and RR2, the result of gene duplication in the common ancestor of both monocots and dicots. RR1 was divided into clades RR1A, RR1B, and RR1C, while RR2 was divided into clades RR2A/DIV1, RR2B/DIV2, and RR2C/DIV3. We demonstrate that among similar antagonistic interactions in An. Majus and So. lycopersicum, RAD-like genes originate from the RAD2 clade, while DIV-like genes originate from distantly related paralogs of the R-R-type lineage. The phylogenetic analyses of these two MYB clades lay the foundation for future comparative studies including testing the evolution of the antagonistic relationship of proteins.

The flower, frequently arranged in clusters known as inflorescences, is one of the most fascinating outcomes through evolution (Endress, 2010). The dimensions of floral diversity in angiosperms are enormous through variations, such as, in floral size, color, shape, scent, and flowering time.

Spiranthes sunii (Orchidaceae), from southern Gansu, China, is described as new. A table is provided to highlight features distinguishing it from the only other species of Spiranthes in China, S. sinensis. Spiranthes sunii, named in recognition of Professor Sun Xuegang (), is known only from the vicinity of Fanba in Wen Xian, Gansu Province. A photo and an analytical drawing are provided. Spiranthes sunii (Orchidaceae) S. sinensis Spiranthes (Spiranthes sunii)

Identifying causes of genetic divergence is a central goal in evolutionary biology. Although rates of nucleotide substitution vary among taxa and among genes, the causes of this variation tend to be poorly understood. In the present study, we examined the rate and pattern of molecular evolution for five DNA regions over a phylogeny of Cornus, the single genus of Cornaceae. To identify evolutionary mechanisms underlying the molecular variation, we employed Bayesian methods to estimate divergence times and to infer how absolute rates of synonymous and nonsynonymous substitutions and their ratios change over time. We found that the rates vary among genes, lineages, and through time, and differences in mutation rates, selection type and intensity, and possibly genetic drift all contributed to the variation of substitution rates observed among the major lineages of Cornus. We applied independent contrast analysis to explore whether speciation rates are linked to rates of molecular evolution. The results showed no relationships for individual genes, but suggested a possible localized link between species richness and rate of nonsynonymous nucleotide substitution for the combined cpDNA regions. Furthermore, we detected a positive correlation between rates of molecular evolution and morphological change in Cornus. This was particularly pronounced in the dwarf dogwood lineage, in which genome-wide acceleration in both molecular and morphological evolution has likely occurred.

The MADS-box gene family encodes critical regulators determining floral organ development. Understanding evolutionary patterns and processes of MADS-box genes is an important step toward unraveling the molecular basis of floral morphological evolution. In this study, we investigated the evolution of PI-like genes of the MADS-box family in the dogwood genus Cornus (Cornaceae). Cornus is a eudicot lineage in the asterids clade, and is intriguing in evolving petaloid bract morphology in two major lineages within the genus. The gene genealogy reconstructed using genomic DNA and cDNA sequences suggests multiple PI-like gene duplication events in Cornus. An ancient duplication event resulted in two ancient paralogs, CorPI-A and CorPI-B, which have highly diverged intron regions. Duplication of CorPI-A further resulted in two paralogs in one subgroup of Cornus, the BW group that does not produce modified bracts. Most species analyzed were found to contain more than one copy of the PI-like gene with most copies derived recently within species. Estimation and comparison of dN/dS ratios revealed relaxed selection in the PI-like gene in Cornus in comparison with the gene in the closely related outgroups Alangium and Davidia, and in other flowering plants. Selection also differed among major gene copies, CorPI-A and CorPI-B, and among different morphological subgroups of Cornus. Variation in selection pressures may indicate functional changes in PI-like genes after gene duplication and among different lineages. Strong positive selection at three amino acid sites of CorPI was also detected from a region critical for dimerization activity. Total substitution rates of the CorPI gene also differ among lineages of Cornus, showing a trend similar to that found in dN/dS ratios. We also found that the CorPI-A copy contains informative phylogenetic information when compared across species of Cornus.

DNA sequences were generated for matK and ITS for 68 and 103 samples of Cornus to reconstruct a species level phylogeny of the genus. The results support the monophyly of most subgenera, except subg. Kraniopsis and subg. Cornus. Subgenus Kraniopsis was suggested to exclude C. peruviana from South America and subg. Afrocrania and subg. Sinocornus were nested within subg. Cornus. Four major clades corresponding to groups also recognizable by morphological differences were revealed: the big-bracted dogwoods (BB) including subg. Cynoxylon, subg. Syncarpea, and subg. Discocrania, the dwarf dogwoods (DW) including subg. Arctocrania, the cornelian cherries (CC) including subg. Cornus, subg. Sinocornus, and subg. Afrocrania, and the blue- or white-fruited dogwoods (BW) including subg. Kraniopsis, subg. Mesomora, and subg. Yinquania. This finding is consistent with previous studies with more limited sampling. The single South American species C. peruviana was found to be sister to the Asian C. oblonga of subg. Yinquania, adding a fourth intercontinental disjunction in the genus that was previously unknown. Species relationships within the subgenera were clearly resolved except for the relatively large subg. Syncarpea and subg. Kraniopsis. Phylogenetic analyses of total evidence combining morphology, matK, ITS, and previously published rbcL and 26S rDNA sequences resolved the relationships among subgenera as (BW(CC(BB,DW))). Biogeographic analyses using DIVA with or without fossils resulted in different inferences of biogeographic history of the genus, indicating the importance of fossil data in biogeographic analyses. The phylogeny based on the total evidence tree including fossils supports an origin and early Tertiary diversification of Cornus in Europe and multiple trans-Atlantic migrations between Europe and North America by the early Tertiary. It also supports that distribution of the few species in the southern hemisphere was not ancestral, but a result of migration from the north. This evidence rejects a previous hypothesis of a southern hemispheric origin of the genus.

Data from four DNA regions (rbcL, matK, 26S rDNA, and ITS) as well as extant and fossil morphology were used to reconstruct the phylogeny and biogeographic history of an intercontinentally disjunct plant group, the cornelian cherries of Cornus (dogwoods). The study tests previous hypotheses on the relative roles of two Tertiary land bridges, the North Atlantic land bridge (NALB) and the Bering land bridge (BLB), in plant migration across continents. Three approaches, the Bayesian, nonparametric rate smoothing (NPRS), and penalized likelihood (PL) methods, were employed to estimate the times of geographic isolations of species. Dispersal and vicariance analysis (DIVA) was performed to infer the sequence and directionality of biogeographic pathways. Results of phylogenetic analyses suggest that among the six living species, C. sessilis from western North America represents the oldest lineage, followed by C. volkensii from Africa. The four Eurasian species form a clade consisting of two sister pairs...

Malpighiaceae possess flowers with a unique bilateral symmetry (zygomorphy), which is a hypothesized adaptation associated with specialization on neotropical oil bee pollinators. Gene expression of two representatives of the CYC2 lineage of floral symmetry TCP genes, CYC2A and CYC2B, demarcate the adaxial (dorsal) region of the flower in the characteristic zygomorphic flowers of most Malpighiaceae. Several clades within the family, however, have independently lost their specialized oil bee pollinators and reverted to radial flowers (actinomorphy) like their ancestors. Here, we investigate CYC2 expression associated with four independent reversals to actinomorphy. We demonstrate that these reversals are always associated with alteration of the highly conserved CYC2 expression pattern observed in most New World Malpighiaceae. In New World Lasiocarpus and Old World Microsteria, the expression of CYC2-like genes has expanded to include the ventral region of the corolla. Thus, the pattern of gene expression in these species has become radialized, which is comparable to what has been reported in the radial flowered legume clade Cadia. In striking contrast, in New World Psychopterys and Old World Sphedamnocarpus, CYC2-like expression is entirely absent or at barely detectable levels. This is more similar to the pattern of CYC2 expression observed in radial flowered Arabidopsis. These results collectively indicate that, regardless of geographic distribution, reversals to similar floral phenotypes in this large tropical angiosperm clade have evolved via different genetic changes from an otherwise highly conserved developmental program.

The repeated origin of similar phenotypes is invaluable for studying the underlying genetics of adaptive traits; molecular evidence, however, is lacking for most examples of such similarity. The floral morphology of neotropical Malpighiaceae is distinctive and highly conserved, especially with regard to symmetry, and is thought to result from specialization on oil-bee pollinators. We recently demonstrated that CYCLOIDEA2–like genes (CYC2A and CYC2B) are associated with the development of the stereotypical floral zygomorphy that is critical to this plant–pollinator mutualism. Here, we build on this developmental framework to characterize floral symmetry in three clades of Malpighiaceae that have independently lost their oil bee association and experienced parallel shifts in their floral morphology, especially in regard to symmetry. We show that in each case these species exhibit a loss of CYC2B function, and a strikingly similar shift in the expression of CYC2A that is coincident with their shift in floral symmetry. These results indicate that similar floral phenotypes in this large angiosperm clade have evolved via parallel genetic changes from an otherwise highly conserved developmental program.

The evolution of floral zygomorphy is an important innovation in flowering plants and is thought to arise principally from specialization on various insect pollinators. Floral morphology of neotropical Malpighiaceae is distinctive and highly conserved, especially with regard to symmetry, and is thought to be caused by selection by its oil-bee pollinators. We sought to characterize the genetic basis of floral zygomorphy in Malpighiaceae by investigating CYCLOIDEA2 -like ( CYC2 -like) genes, which are required for establishing symmetry in diverse core eudicots. We identified two copies of CYC2 -like genes in Malpighiaceae, which resulted from a gene duplication in the common ancestor of the family. A likely role for these loci in the development of floral zygomorphy in Malpighiaceae is demonstrated by the conserved pattern of dorsal gene expression in two distantly related neotropical species, Byrsonima crassifolia and Janusia guaranitica . Further evidence for this function is observed in a Malpighiaceae species that has moved to the paleotropics and experienced coincident shifts in pollinators, floral symmetry, and CYC2 -like gene expression. The dorsal expression pat-tern observed in Malpighiaceae contrasts dramatically with their actinomorphic-flowered relatives, Centroplacaceae ( Bhesa paniculata) and Elatinaceae ( Bergia texana ). In particular, B. texana exhibits a previously undescribed pattern of uniform CYC2 expression, suggesting that CYC2 expression among the actinomorphic ancestors of zygomorphic lineages may be much more complex than previously thought. We consider three evolutionary models that may have given rise to this patterning, including the hypothesis that floral zygomorphy in Malpighiaceae arose earlier than standard morphology-based character reconstructions suggest.

The eastern Asian (EAS)-eastern North American (ENA) floristic disjunction is one of the best-known biogeographic patterns in the Northern Hemisphere. Recent paleontological and molecular analyses have illuminated the origins of the biogeographic pattern, but subsequent diversification and evolution of the disjunct floras in each of the two continents after isolation remains poorly understood. Although similar in climate and floristic composition, EAS has twice as many species as ENA in genera occurring in both regions. Explaining such differences in species diversity between regions with similar environmental conditions (diversity anomalies) is an important goal of the study of the global patterns of biodiversity. We used a phylogenetic approach to compare rates of net speciation and molecular evolution between the two regions. We first identified EAS-ENA disjunct sister clades from ten genera (Asarum, Buckleya, Carpinus, Carya, Cornus, Hamamelis, Illicium, Panax, Stewartia, and Styrax) that represent diverse angiosperm lineages using phylogenetic analyses of ITS (internal transcribed spacer of nuclear ribosomal DNA) sequence data. Species richness and substitution rate of ITS between sister clades were compared. The results revealed a pattern of greater species diversity in the EAS counterparts. A positive relationship between species diversity and ITS substitution rate was also documented. These results suggest greater net speciation and accelerated molecular evolution in EAS. The data support the idea that a regional difference in net speciation rate related to topographic heterogeneity contributes to the diversity anomaly between EAS and ENA. The close relationship between rates of ITS evolution and species richness further suggests that species production may be directly linked to rate of nucleotide substitution.

Sequences of the chloroplast trnL-F region and 3′ end ndhF gene were used to elucidate phylogenetic relationships and the delimitation of families within Dipsacales s.l. Parsimony analyses of individual and combined data were conducted using maximum parsimony method. The most parsimonious tree based on combined trnL-F and 3′ end ndhF data set recognizes seven major clades of Dipsacales s.l. with the following relationships: Apiales (Adoxaceae ((Diervillaceae, Caprifoliaceae s.str.) (Linnaeaceae (Morinaceae (Dipsacaceae, Valerianaceae))))). Both Sambucus and Viburnum have close relationships with Adoxaceae, supporting their inclusion in this family. Caprifoliaceae s.l. (excluding Sambucus and Viburnum) is polyphyletic, and comprises three clades or families, i.e., Linnaeaceae (Abelia, Dipelta, Kolkwitzia, and Linnaea), Diervillaceae (Weigela and Diervilla) and Caprifoliaceae s.str. (Heptacodium, Leycesteria, Lonicera, Symphoricarpos, and Triosteum). This study focuses on the systematic position of Heptacodium, Triplostegia, and Morinaceae; and suggests that Heptacodium is closely related to the other Caprifoliaceae s.str.; Triplostegia is a sister to Dipsacaceae; Morinaceae, which has an affinity with Dipsacaceae, is possibly a sister group with Dipsacaceae–Valerianaceae clade. Our results are highly congruent with those of Bell et al. (2001) and Donoghue et al. (2001) .