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Background and Aims Artemisia is a mega-diverse genus consisting of ~400 species. Despite its medicinal importance and ecological significance, a well-resolved phylogeny for global Artemisia, a natural generic delimitation and infrageneric taxonomy remain missing, owing to the obstructions from limited taxon sampling and insufficient information on DNA markers. Its morphological characters, such as capitulum, life form and leaf, show marked variations and are widely used in its infrageneric taxonomy. However, their evolution within Artemisia is poorly understood. Here, we aimed to reconstruct a well-resolved phylogeny for global Artemisia via a phylogenomic approach, to infer the evolutionary patterns of its key morphological characters and to update its circumscription and infrageneric taxonomy. Methods We sampled 228 species (258 samples) of Artemisia and its allies from both fresh and herbarium collections, covering all the subgenera and its main geographical areas, and conducted a phylogenomic analysis based on nuclear single nucleotide polymorphisms (SNPs) obtained from genome skimming data. Based on the phylogenetic framework, we inferred the possible evolutionary patterns of six key morphological characters widely used in its previous taxonomy. Key Results The genus Kaschgaria was revealed to be nested in Artemisia with strong support. A well-resolved phylogeny of Artemisia consisting of eight highly supported clades was recovered, two of which were identified for the first time. Most of the previously recognized subgenera were not supported as monophyletic. Evolutionary inferences based on the six morphological characters showed that different states of these characters originated independently more than once. Conclusions The circumscription of Artemisia is enlarged to include the genus Kaschgaria. The morphological characters traditionally used for the infrageneric taxonomy of Artemisia do not match the new phylogenetic tree. They experienced a more complex evolutionary history than previously thought. We propose a revised infrageneric taxonomy of the newly circumscribed Artemisia, with eight recognized subgenera to accommodate the new results., This work was supported by the National Natural Science Foundation of China (grant nos. 31870179, 31570204, 31270237 and J1310002), the International Partnership Program (grant no. 151853KYSB20190027), Sino-Africa Joint Research Center (grant no. SAJC201614), Key technology projects of Jiangxi Province's major scientific and technological research and development project (grant no. 20223AAF01007), Survey of Wildlife Resources in Key Areas of Tibet (grant no. ZL202203601) and National Plant Specimen Resource Center (grant no. E0117G1001) of the Chinese Academy of Sciences, Key Project at Central Government Level: The Ability Establishment of Sustainable Use of Valuable Chinese Medicine Resources (grant no. 2060302) and Project of the Central Siberian Botanical Garden of the Siberian Branch of the Russian Academy of Sciences (grant no. AAAA-A21-121011290024-5)., INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION Conclusions SUPPLEMENTARY DATA FUNDING ACKNOWLEDGEMENTS CONFLICT OF INTEREST LITERATURE CITED Supplementary data

The genetic diversity and structure of Pulsatilla cernua, a continental‐grassland relict, were investigated using variations in chloroplast DNA (cpDNA) and microsatellites of nuclear DNA. In the analyses of three cpDNA regions, 17 haplotypes were found in 24 populations of P. cernua from Japan, Korea, and Russia. Although the route and time of migration between the continent of Asia and Japan could not be well resolved, the cpDNA haplotype network suggests the existence of several ancient lineages in Japan and a recent secondary migration from Japan to the continent. Microsatellite analyses did not indicate genetic structure among the Japanese populations, indicating the existence of gene flow across the distribution area until recently. These results indicate that the present fragmentation of P. cernua in Japan may reflect a rapid, recent reduction from a previously large, continuous distribution.

To elucidate the origin and migration history of the “Mansen elements,” a group of temperate grassland plants mainly distributed in northeastern Asia, phylogeographic analyses based on chloroplast DNA markers and double-digest restriction site-associated DNA sequencing (ddRAD-seq) data were performed on Viola orientalis, one of the representative species of the group. Phylogenetic analyses using ddRAD-seq data revealed that the populations of V. orientalis were clustered into five clades, among which the continental clades made of populations from Russia and Korea diverged more than 100,000 years earlier than the Japanese clades. The Japanese clade likely diverged during the last glacial period, followed by a further post-glacial divergence into the Kyushu and the Honshu subclades. Our study demonstrated that V. orientalis originated in the continental area of northeastern Asia and, during the last glacial period, has spread southward through the Korean Peninsula across the Japanese Islands. This finding supports the previously proposed evolutionary hypothesis regarding the origin and migration routes of the Mansen elements.

Cardamine occulta, recently reported also as 'Asian C. flexuosa', is originally a native East Asian weed of paddy fields and other open habitats. It has been recorded throughout the world and is now also spreading widely in Europe. However, how this species differs morphologically from European C. flexuosa and its closest relatives in Asia (C. kokaiensis and C. scutata) is not fully known, particularly because it became widely recognized as a new taxon only recently. We used chromosome counting and flow cytometry to determine ploidies and genome size variation in these four species and morphometric analyses to ascertain their morphological differentiation. A uniformly octoploid level (2n = 64) is confirmed here for C. occulta and a tetraploid level for C. flexuosa and C. scutata (2n = 32). Here we formally describe C. kokaiensis, which is restricted to East Asia (Japan, Honshu; eastern China, Zhejiang Province; perhaps also the Russian Far East) and determine it to be a tetraploid. Considerable differences in monoploid genome size were revealed between these taxa, suggesting their mostly allopolyploid origins. Morphological differences between the species are demonstrated, and detailed morphological descriptions and an identification key are provided.

Background and aims Domatia are plant structures within which organisms reside. Callicarpa saccata (Lamiaceae) is the sole myrmecophyte, or ‘ant plant’, that develops foliar (leaf-borne) myrmeco-domatia in this genus. In this work we examined domatium development in C. saccata to understand the developmental processes behind pouch-like domatia. Methods Scanning electron microscopy, sectioning and microcomputed tomography were carried out to compare the leaves of C. saccata with those of the closely related but domatia-less myrmecophyte Callicarpa subaequalis, both under cultivation without ants. Key results Callicarpa saccata domatia are formed as a result of excess cell proliferation at the blade/petiole junctions of leaf primordia. Blade/petiole junctions are important meristematic sites in simple leaf organogenesis. We also found that the mesophyll tissue of domatia does not clearly differentiate into palisade and spongy layers. Conclusions Rather than curling of the leaf margins, a perturbation of the normal functioning of the blade/petiole junction results in the formation of domatium tissue. Excess cell proliferation warps the shape of the blade and disturbs the development of the proximal–distal axis. This process leads to the generation of distinct structures that facilitate interaction between C. saccata and ants.

As part of the Mapping Asia Plants (MAP) project, floristic works for Northeast Asia (i.e., China, Japan, the Korean Peninsula, and Mongolia) have been surveyed and compared. From the 18th century to the beginning of the 20th century, most floristic research in Northeast Asia was performed by European nations. Since then, local botanists have directed the course of floristic research. Although a “Flora of Northeast Asia” has yet to be published, several materials covering more than one country have published, from Maximowicz’s “Primitiae Florae Amurensis” (1895) to Ma’s “A Checklist of Woody Plants from Eastern Asia” (2017). However, the status of floristic information in Northeast Asia varies widely by country. China, Japan, and the North Korea published the latest editions of their floras in 2020, 2013, and 2000, respectively. Both Mongolia and South Korea have published several volumes of their latest floras and plan to complete them in the next few years. Together, these works give an overall picture of the flora of Northeast Asia. While every country in Northeast Asia has at least one plant species checklist, the availability of digital specimen records varies from 1.3 per species to 387.1 per species. Factors that currently hinder research include variation among works in how terms are used, in writing style, and taxonomic treatments, in addition to a lack of specimens for Mongolia and the Korean Peninsula. Some floras are written in their native languages and may be difficult to access for general researchers. In a few years, after the completion of the “Flora of Mongolia”, the “Flora of Korea”, and a local flora for Northeast China, floristic research in Northeast Asia will enter a new stage. Using floristic information currently available, a total of 336 families, 3506 genera, and nearly 40,000 species of vascular plants were identified in Northeast Asia.

Because of the shape of a double-lumen tube (DLT), it is more difficult to use for intubation than an ordinary endotracheal tube. We prospectively investigated the usefulness of the Airtraq DLAt Tokai University Hachioji Hospital, anesthesiologists with ≥ 5 years' clinical experience intubated a tracheal intubation training mannequin with DLTs using the Airtraq DLThe mean time required for intubation was shorter in the adapter phase than in the Airtraq-alone phase for all anesthesiologists (adapter phase, 9.05±2.48 seconds; Airtraq-alone phase, 10.67±2.19 seconds).The use of Airtraq DL

The genus Stevia comprises approximately 200 species, which are distributed in North and South America, and are representative of the species diversity of the Asteraceae in the New World. We reconstructed the phylogenetic relationships using sequences of ITS and cpDNA and estimated the divergence times of the major clade of this genus. Our results suggested that Stevia originated in Mexico 7.0–7.3 million years ago (Mya). Two large clades, one with shrub species and another with herb species, were separated at about 6.6 Mya. The phylogenetic reconstruction suggested that an ancestor of Stevia was a small shrub in temperate pine–oak forests and the evolutionary change from a shrub state to a herb state occurred only once. A Brazilian clade was nested in a Mexican herb clade, and its origin was estimated to be 5.2 Mya, suggesting that the migration from North America to South America occurred after the formation of the Isthmus of Panama. The species diversity in Mexico appears to reflect the habitat diversity within the temperate pine–oak forest zone. The presence of many conspecific diploid–polyploid clades in the phylogenetic tree reflects the high frequency of polyploidization among the perennial Stevia species.

A new species, Callicarpa bachmaensis Soejima & Tagane, sp. nov., is described and illustrated from Bach Ma National Park in Thua Thien Hue Province, Central Vietnam. This species has a characteristic liana habit, white corolla, and narrowly elliptic to narrowly lanceolate, entire, occasionally subequal leaves, by which it is clearly distinguished from the other previously known species of this genus.

A tropical small tree, Callicarpa saccata, is known to have a symbiotic relationship with ants. It has sac-like structures at the base of the leaves that are inhabited by ants. No other species has been determined to be a myrmecophyte among the ca. 140 species of this genus. However, our recent field investigation discovered that two other species on Borneo (C. barbata and C. teneriflora) have hollow stems, which seem to be inhabited by ants. We observed the morphological features of these species in relation to their usage by ants, and became convinced that they are mymecophytic species. The molecular phylogenetic analyses using ITS and chloroplast regions suggest that C. saccata and C. teneriflora are closely related, but the differences in the myrmecophytic features of these species should be noted.

Aegagropila linnaei is a freshwater green alga of the order Cladophorales, which is well known as ‘Marimo’ in Japan for its beautiful spherical form as lake balls in Lake Akan. Lake Akan is the only lake in which spherical ‘Marimo’ is found in Japan, but the species also grows as floating or epilithic filaments which appear in several other Japanese lakes. The spherical growth form usually reproduces vegetatively, and it is not known if the species also reproduces sexually or whether transformation between different growth forms happens in natural populations. In this study, the genetic diversity of A. linnaei in Japan was investigated using isozyme analysis. Apart from one colony in Lake Ogawara, each colony was genetically homogeneous, which suggests that asexual reproduction is dominant. All the non-epilithic (spherical aggregations, floating filaments, and floating tufts) colonies in Lake Akan were genetically similar, regardless of the location of sites within the lake, while epilithic colonies have different genetic structures. Therefore, transformation or gene flow between epilithic and non-epilithic forms is not evident in natural populations. Because the genetic diversity largely depends on epilithic algae in Lake Akan, it is important to conserve epilithic- as well as spherical-colonies.

The phylogenetic relationships of Nolana (Nolaneae, Solanaceae) were constructed using partial sequences (ca. 891 bp) of the granule-bound starch synthase I (GBSSI) or the waxy gene. Nolana, with 89 species, is primarily distributed in coastal Chile (49 spp.) and Peru (43 spp.), and of these, four species are recorded in Peru and Chile, and another from the Galapagos Islands, Ecuador. Our phylogenetic analysis, utilizing a sampling of 63 of the 89 species, supports the monophyly of Nolana and recovered three clades with 95%-100% bootstrap support. Nolana sessiliflora is the sister taxon to the remainder of the genus. Two large, highly supported clades are evident; one containing taxa from Chile, Peru and the Galapagos Islands, and another containing taxa from Chile and Peru. Nolana galapagensis, an endemic to the Galapagos Islands, is suggested to be sister to N. arenicola in a clade that also includes N. adansonii from southern Peru and northern Chile. These two species differ substantially in habitat preference, habit, leaf shape, and mericarp morphology. The monophyly is confirmed for a morphologically cohesive group composed of N. acuminata, N. baccata, N. elegans, N. reichei, N. parviflora, N. pterocarpa, and N. paradoxa, a clade of essentially Chilean species.

Chromosome numbers were determined from microsporocytes (meiotic counts) and root-tip cells (mitotic counts) in 201 collections of 51 genera and 119 specific and infraspecific taxa belonging to nine tribes of Asteraceae and Acicarpha spathulata R. Br. of Calyceraceae from Australia, Bolivia, Brazil, Chile, Mexico, and the United States. These include the first reports and new numbers for the basal members of the Barnadesieae and Mutisieae. First reports are provided for 45 taxa, including five genera, Dasyphyllum HBK (2n = 54), Dithyrostegia A. Gray (2n = 14), Epitriche Turcz. (2n = 10), Revealia R. M. King & H. Rob. (2n = 22), and Stifftia J. C. Mikan (2n = 54). In addition, new chromosome numbers are established at the generic level in the genera Barnadesia Mutis (2n = 54), Eremanthus Less. (2n = 34, 30), Macvaughiella R. M. King & H. Rob. (2n = 24), and Trichocline Cass. (2n = 38), and in 12 additional species. Remaining counts augment and agree with previously reported determinations. The base chromosome numbers of Calyceraceae and Asteraceae are discussed in published records and our original counts.

The karyotype of diploid Aster iinumae is morphologically similar to that of diploid Aster ageratoides var. ageratoides, however, its chromosome size is apparently smaller (S-type chromosomes versus L-type chromosomes, respectively). The hybrid origin of tetraploid Aster microcephalus var. ovatus (LS-type chromosomes) has previously been suggested by cytogenetics and chloroplast DNA (cp DNA) data. The cp DNA phylogeny also implies that the S-type chromosome is apomorphic, which means that genome size reduction occurred on the evolutionary way to A. iinumae. In this study, we have demonstrated that the chromosome size difference does not depend on the intensity of chromosome condensation but on the DNA content. The simultaneous genomic in situ hybridization (GISH) results show the similarity between S-type chromosomes of A. iinumae and A. microcephalus var. ovatus, and between L-type chromosomes of A. ageratoides and A. microcephalus var. ovatus, which provide additional evidence for A. microcephalus var. ovatus being a tetraploid amphidiploid produced by hybridization between S-type chromosomes and L-type chromosomes. The distribution patterns of Ty1-copia-like retrotransposons were similar in L- and S-type chromosomes. The copies of this retrotransposon dispersed uniformly on all chromosomes, and it is not yet apparent how the Ty1-copia-like retrotransposon affects the size difference between them.

Phylogenetic analysis of 105 nuclear GAI1 sequences of Vitaceae provided a fairly robust phylogeny, largely congruent with the recently published chloroplast data of the family. In the GAI1 phylogeny, Cayratia Juss., Tetrastigma (Miq.) Planch., and Cyphostemma (Planch.) Alston form a clade. Cyphostemma and Tetrastigma are both monophyletic, and Cayratia is paraphyletic. Ampelopsis Michx is paraphyletic with the African Rhoicissus Planch. and the South American Cissus striata Ruiz & Pav. and its close relatives (e.g., Cissus simsiana Roem. & Schult.) nested within it. The pinnately leaved Ampelopsis forms a subclade, and the simple and palmately leaved Ampelopsis constitutes another subclade. All species of Cissus L. sampled from Asia, Africa, and Central and South America (except the C. striata complex) form a monophyletic group. Pterisanthes Blume of southeastern Asia forms a clade with the Asian Ampelocissus Planch. Vitis L. is monophyletic and forms a larger clade with the tropical Ampelocissus and Pterisanthes . Parthenocissus Planch., forms a clade with Yua C.L. Li, with each genus reportedly monophyletic. Cissus from the Old World is paraphyletic with the neotropical core Cissus nested within it. The basal grade of Cissus consists of taxa from Africa. The African-Asian biogeographic relationships are complex, with several intercontinental disjunctions. The Northern Hemisphere Ampelopsis is most closely related to the South American C. striata complex and the African Rhoicissus .

The phylogenetic relationship among 30 accessions belonging to nine species of the genus Echinochloa Beauv. was studied on the basis of the sequence of three non-coding regions (trnT-L, trnL-F intergenic spacers, and trnL intron) of chloroplast DNA (cpDNA). A strict consensus parsimonious tree of the three most parsimonious trees derived from 25 polymorphic sites (six indels and 19 substitutions) in the total sequences, ranging from 1715–1760 bp, represented five groups: (i) Echinochloa oryzicola Vasing. and Echinochloa stagnina Beauv. from Thailand; (ii) Echinochloa crus-galli Beauv. complex; (iii) Echinochloa crus-pavonis Schult; (iv) Echinochloa colonum Link. and Echinochloa frumentacea Link.; and (v) the African species, Echinochloa obtusiflora Stapf and Echinochloa stagnina. Japanese barnyard millet (Echinochloa esculenta H. Scholz) and various weedy varieties of E. crus-galli and Echinochloa oryzoides Fritsch had quite similar sequences and formed the E. crus-galli complex, which was characterized by six substitutions. A cultivated form of E. oryzicola (Mosuo barnyard millet) and various morphological and agronomical forms of E. oryzicola were characterized by two indels. Indian barnyard millet (E. frumentacea) and its wild counterpart (E. colonum) were characterized by five substitutions. Domestication as millets and adaptation to paddy environments as mimic weeds might occur after the divergence of species in the Asian Echinochloa.

Detailed karyotypes of diploid Aster ageratoides var. ageratoides (2n=18), diploid A. iinumae (=Kalimeris pinnatifida) (2n=18) and tetraploid A. microcephalus var. ovatus (2n=36) were constructed on the basis of chromosome lengths, arm ratios and multi color fluorescence in situ hybridization (McFISH) with 5S and 18S ribosomal RNA gene sequences as probes. The karyotype of A. iinumae was morphologically similar to those of A. ageratoides var. ageratoides, however, the size of the chromosomes of A. iinumae was apparently smaller (S-type chromosomes) compared to those of A. ageratoides (L-type chromosomes). The chromosomes of A. microcephalus var. ovatus, a putative amphidiploid between them consisted of the 18 large chromosomes (L-type chromosomes) and the 18 smaller chromosomes (S-type chromosomes). The McFISH with 5S rDNA and 18S rDNA of each A. ageratoides and A. iinumae chromosomes tagged 4 out of 18 chromosomes. Whereas A. microcephalus var. ovatus have 5S rDNA and 18S rDNA sites equal to the sum of the numbers in the two diploids (A. ageratoides and A. iinumae), 4 on the L-type chromosomes and 4 on the S-type chromosomes. The locations of the rDNA sites in A. microcephslus var. ovatus are corresponding to those of A. ageratoides and A. iinumae.

Cytogeographical studies have revealed the distribution of sexual diploids and agamospermous polyploids of Stevia ovata and four related species: Stevia nepetifolia, Stevia oligophylla, Stevia origanoides and Stevia triflora in Mexico. These species are distributed mainly in the temperate and subhumid montane region. Agamospermous triploids are the forms most abundantly and widely distributed geographically in each of the five species. Diploids occur in low frequencies except in S. origanoides. For the five species, diploids are restricted mainly to the temperate montane ranges of the south-western Pacific side of Mexico, but they also occur sporadically in the relatively isolated areas from Oaxaca to Durango, Mexico D. F. and Nuevo Leon. Although the distribution of the temperate forests must have moved southward and northward following climatic fluctuations, even in the lower latitudes of Mexico, the largely stable temperate vegetation could have been maintained along the Y-shaped montane ranges (Sierra Madre del Oriental, Sierra Madre del Occidental, Sierra Madre del Sur and the Trans-Mexico Volcanic Belt) and have provided some refuge areas. The present distribution ranges of sexual diploids of some species of Stevia in Mexico indicate that diploids were not restricted to a single refuge during the last ice age.

Thirteen new species of the genusStevia are described and illustrated from Mexico:S. chilapensis, S. coahuilensis, S. crassifolia, S. ecatepecana, S. filodecaballoana, S. mascotensis, S. mexicana, S. oaxacana, S. oligophylla, S. potosina, S. rotundifolia, S. scabrelloides, andS. viejoana. In addition, two varieties,Stevia aschenborniana Sch. Bip. ex Klotzsch var.occidentalis Grashoff andS. palmeri A. Gray var.constricta Grashoff are herein redefined as being distinct species,S. occidentalis andS. constricta stat. nov.Stevia mexicana resemblesStevia trifida Lagasca but differs in the habit.

Chromosome numbers from 244 accessions representing 73 species, five varieties and two putative species hybrids in Mexican Stevia are reported with comments on agamospermy, cytogeography and chromosomal evolution. The chromosome numbers of 47 species and two varieties were counted for the first time. Counts of 12 species and two varieties were new cytotypes, or differed from all previously reported numbers for the same species. B chromosomes were found in 16 species and two varieties. All species of shrubs or shrublets were sexual diploids (2n = 24). Perennial herbs were diploids or polyploids based on x = 11 or 12 and the widespread prevalence of agamospermous polyploids was revealed. Chromosome numbers of annual herbs varied from 2n = 24 to 2n = 8. The cytogeographical survey revealed five distributional patterns of agamic complexes based on the relative abundance of polyploids compared to their diploid ancestors. The wider distributional range (extending to northern and inland areas) of some agamospermous polyploids have been achieved by recent colonization accompanying climatic warming after the last glaciation. This has occurred even in lower latitudes such as Mexico, due to more successful founder population reproduction and the acceleration of seed dispersal, as well as the creation of new and open habitats by human activities.

The present study examined the effects of group size and percentage of the subjects starting with majority behavior upon the process of achieving behavioral uniformity. Four groups of 12 and five groups of 24 subjects were formed. The starting points at the beginning of the experiments were set to 50%, 67%, and 83%. Each subject was given a B5 size card having different colors on the front and the back and showed either side of the cards to others. Subjects shared the goal of achieving uniformity by selecting one of two color options. Analysis indicated that group size did not affect time to complete unanimity and a logistic function was found between the transition probability and the rate of diffusion. According to a Markov model, subjects do not react to the past history of the group. We found that the transition probability was dependent upon not only the percentage of individuals at a given moment but also the initial value in the beginning. This means that the transition probability was influenced by past history.

RFLPs of cpDNA were examined for 18 species ofAster, six species ofKalimeris, two species ofMiyamayomena and one species and one variety ofHeteropappus from Japan, using 16 restriction endonucleases. Approximately 275 restriction sites were surveyed, and a total of 74 restriction site mutations was detected, and 31 of these were phylogenetically informative. Sixteen most parsimonious trees constructed from Wagner parsimony analysis indicated the polyphyly ofKalimeris andMiyamayomena sensu Kitamura;K. miqueliana belongs to a different clade from the remaining species ofKalimeris, and two species ofMiyamayomena did not make a single clade. This result suggests that the shortening or loss of pappus have happened parallelly in different evolutionary lineages. We must be careful to assess the pappus character in taxonomy and phylogeny, and it is desirable to examine their phylogenetic relationships using a molecular data.

Genetic variation in an endangered tree species, Chionanthus retusus, was examined using enzyme electrophoresis. This species occurs in East Asia from Japan to Taiwan and southern China. In Japan, however, it occurs only in two restricted areas: at the northernmost tip of Tsushima Island between Japan and Korea, and in the eastern Gifu Prefecture (Tono region) of central Honshu. In the Tono region, the habitat of C. retusus is becoming fragmented under the influence of human activity and each stand contains a few individuals of C. retusus, while the population on Tsushima consists of approximately 1000 individuals. From the fossil evidence, C. retusus has been distributed continuously including the both two regions, and the present distribution is apparently relic in Japan. In contrast to the Tono population, the population of Tsushima seems to be stable. Comparing the genetic diversity and differentiation of the populations between these two regions should shed light on how a relic woody long-lived plant keeps and/or looses its genetic diversity, and how a population differentiates from other disjunct populations. Allozyme electrophoresis of 18 loci for the Tono region indicated that 22.2% of the loci are polymorphic (P) with a gene diversity of (h) 0.087. The population of Tsushima has 38.9% polymorphic loci and a gene diversity of 0.149. We could not find any spatial genetic structure of C. retusus in the Tono region by spatial autocorrelation analysis. These results suggest that considerable genetic variation is still present in the Tono region and the influence of the recent habitat fragmentation seems not so large, yet. Because C. retusus is a long-lived tree, the population history may hinder the effect of the fragmentation at present. The genetic diversity (GST) between the populations of the Tono and Tsushima is 0.280, showing the genetic differentiation between these two regions has occurred.

The genusPittosporum includes about 160 species. Four species ofPittosporum occur in the Bonin Islands, and all of these are endemic to the islands. Electrophoretic studies of the four endemic species,P. tobira, from the Japanese mainland, andP. lutchuense var.denudatum from the Ryukyu Islands, were used to determine the origin and speciation pattern of the endemic species.

The long-term measurement of singlet oxygen like oxydants (SOLO) in polluted ambient air by use of the chemical determination method with α-terpinene (Ter) as a substrate was carried out. α-Terpinene endoperoxide, ascaridole (Asc), was produced by the reaction of SOLO with Ter in a similar manner to singlet oxygens (1O2). Asc formed was analyzed by gas chromatography-mass fragmentgraphy with selected ion monitoring mode.The concentration of SOLO in sample air was calculated from the amount of Asc determined, and expressed as O2 in active state. The concentration of 4 – 21 ppb of SOLO was detected in the daytime, and it reached to the maximum at around noon. SOLO were also detected in the nighttime and its concentration reached to the maximum at around midnight. The pattern of diurnal change of SOLO concentration was apparently different from that of photochemical oxidants including ozone, but identical with that of NOx. SOLO are not conventional photochemical oxidants such as ozone, but must be α-terpinene endoperoxide producible oxydants having similar reactivity to 1O2 and probably including 1O2 themselves.

RFLPs of cpDNA of five species and one variety ofKalimeris, and elght species ofAster from Japan were investigated. Approximately 290 restriction sites were surveyed using 16 restriction enzymes. A total of 52 restriction site mutations was detected, and 21 of them were phylogenetically informative. Wagner parsimony analysis resulted in only one most parsimonious tree. In the tree obtained,Kalimeris sensu Kitamura is a colyphyletic group;K. miqueliana belongs to a different clade than the remaining species ofKalimeris. This result suggests that the shortening of the pappus has occurred in parallel in different evolutionary line. Thus, it is not appropriate to extend the generic circumscription ofKalimeris to includeK. miqueliana, based on pappus length. The sister group ofKalimeris, exceptK. miqueliana, is theAster ageratoides group.Aster ovatus is included in theKalimeris clade and it is suggested that it represents an amphidiploid with someKalimeris species as its maternal parent.

To study the origin and speciation of plants in oceanic islands, electrophoretic analyses have been done on three endemic species ofSymplocos in the Bonin Islands as well as on three other species;S. kuroki, S. nakaharae andS. tanakae which are considered to be closely related to the Bonin endemics. There occur three species:S. kawakamii, S. pergracilis andS. boninensis in Bonin. The genusSymplocos is one which is considered to be diversified in the Bonin Islands.

Seventy-nine species representing 12 genera of Vitaceae were sequenced for the trnL-F spacer, 37 of which were subsequently sequenced for the atpB-rbcL spacer and the rps16 intron. Phylogenetic analysis of the combined data provided a fairly robust phylogeny for Vitaceae. Cayratia, Tetrastigma, and Cyphostemma form a clade. Cyphostemma and Tetrastigma are each monophyletic, and Cayratia may be paraphyletic. Ampelopsis is paraphyletic with the African Rhoicissus and the South American Cissus striata nested within it. The pinnately leaved Ampelopsis form a subclade, and the simple and palmately leaved Ameplopsis constitutes another with both subclades containing Asian and American species. Species of Cissus from Asia and Central America are monophyletic, but the South American C. striata does not group with other Cissus species. The Asian endemic Nothocissus and Pterisanthes form a clade with Asian Ampelocissus, and A. javalensis from Central America is sister to this clade. Vitis is monophyletic and forms a larger clade with Ampelocissus, Pterisanthes, and Nothocissus. The eastern Asian and North American disjunct Parthenocissus forms a clade with Yua austro-orientalis, a species of a small newly recognized genus from China to eastern Himalaya. Vitaceae show complex multiple intercontinental relationships within the northern hemisphere and between northern and southern hemispheres.

Genetic differentiation was examined betweenAdiantum capillus-veneris L. andA. ogasawarense Tagawa. A total of 136 individuals from two populations ofA. ogasawarense and three populations ofA. capillus-veneris were sampled. Allozymes encoded by 19 putative loci for nine enzyme systems were observed. The populations ofA. ogasawarense are genetically differentiated from those ofA. capillus-veneris; conspecific populations cluster together. However, genetic identity between two species was estimated to be 0.815, and indicates that the degree of allozyme differentiation is lower than those between endemic flowering plants and their progenitors. It is possible that the low genetic differentiation observed betweenA. ogasawarense andA. capillus-veneris results from a recent origin of the endemic species,A. ogasawarense.

TheAster leiophyllus complex is complicated taxonomically and includes many related taxa representing polyploid series. It has been reported that this group is diversified throughout the Kanto district, central Japan, and there are three taxa endemic to the Kanto district. However, as neither morphological variation range nor distribution pattern is sufficiently investigated, taxonomic confusion sometimes occurs. In this study, morphological variation was examined in relation to the ploidy level, and taxonomic consideration was given. As a result, four morphologically recognized taxa occur in the Kanto district;A. leiophyllus (2x, 6x),A. leiophyllus var.sawadanus (2x, 3x, 4x),A. semiamplexicaulis (2x), andA. sugimotoi (4x, 5x). The distribution ranges ofA. leiophyllus var.sawadanus, A. semiamplexicaulis andA. sugimotoi are small, whileA. leiophyllus is distributed over most of the Kanto district. Morphological and cytological observations indicate that one of the reasons of the taxonomic confusion is the presence of presumed hybridization betweenA. leiophyllus and other taxa.

The mode of initiation and development of integuments was investigated in six species of five genera in Menispermanceae, which have bitegmic and unitegmic ovules. The species investigated have similar integumentary structures at maturity in each of the bitegmic and unitegmic ovules. In bitegmic ovules (e.g.Cocculus), both integuments are for the most part two-cell layered. The initiation of inner integument (ii) begins with divisions of dermal cells of the nucellar primordium. The initiation of the outer integument (oi) commences with divisions of subdermal cells. In unitegmic ovules (e.g.Stephania), the integument is initiated by periclinal divisions of dermal cells, and cells of subdermal origin (which may represent the oi in case of bitegmy) form a small swelling on the raphal side and, on the antiraphal side, are included in the base of the single integument. Unitegmy of Menispermanceae (at least in the case of the genera investigated) seems to have been derived through elimination of oi, rather than through “integumentary shifting” (Bouman and Calis, 1977), a process suggested for explanation of unitegmy as in Ranunculaceae.

Thirty species and one variety of Symplocos (Symplocaceae), including all taxa distributed in Japan, were phylogenetically analyzed with DNA sequence data. The evolution of morphological characters is discussed on the basis of the phylogenetic relationships obtained. All species were Asian, except one, S. austromexicana, from Mexico. The nuclear ribosomal internal transcribed spacer (ITS) region and two intergenic spacer regions, between trnL and trnF, and between trnH and psbA of chloroplast DNA were used. The topologies of trees obtained from ITS and the chloroplast intergenic spacers are largely congruent. S. sonoharae, the representative of the subgenus Symplocos in Asia, was sister to all other species. The position of the American species, S. austromexicana, which also belongs to the subgenus Symplocos, was not well resolved. The phylogenetic tree based on combined sequence data largely supports the monophyletic origin of the infrageneric sections proposed earlier. However, the phylogenetic relationship between them is not well resolved, probably due to rapid diversification. The section Palura, a deciduous group, is well defined in the DNA analysis, suggesting its independent status in the genus Symplocos. In spite of their morphological divergence, the three endemic species of the Bonin Islands are monophyletic. The occurrence of curved seeds seems to be homoplastic, scattered over the phylogenetic tree without showing a particular infrageneric relationship.

Received 5 October 2007. Published on the NRC Research Press Web site at canjbot.nrc.ca on 27 November 2007. J. Wen.1 Department of Botany, MRC 166, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013-7012, USA; Laboratory of Systemic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P. R. China. Z. Nie and Y. Meng. Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650204, P. R. China; Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China. A. Soejima. Department of Biological Science, School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan. 1Corresponding author (e-mail: wenj@si.edu). 1018