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To date, little is known about the past evolutionary trajectories of rare and endangered orchids native to mainland China, Japan, and Korea (the CJK region). In this study, we focus on two endangered orchids, Cypripedium japonicum(present in the three countries) and C. formosanum(endemic to Taiwan), to understand the divergence/speciation models that would have been operating in this group, including genetic diversity, geographic structure, and colonization pathways across the region. Using a combination of five cpDNA regions, we reconstructed phylogenetic trees and investigated the genetic diversity/structure of 20 populations. Ecological niche modeling was used to gain insight into the paleodistribution and dispersal corridors at the Last Glacial Maximum and to survey climatic niche differences. Populations from mainland China + Korea, Japan, and Taiwan formed three distinct monophyletic lineages and were placed into separate genetic clusters, agreeing with geographic barriers and species boundaries. Populations of C. japonicumin mainland China harbored the highest diversity, suggesting the presence of multiple glacial refugia. The Korean populations would have originated from either western/central or eastern China, probably using a dispersal corridor across the East China Sea shelf. The divergence of C. formosanumis proposed under an allopatric speciation model, also highly influenced by a climate niche shift. In the context of previous studies, a deep divergence in cpDNA sequences between Chinese + Korean and Japanese populations of C. japonicummay be taken as an example of the speciation events of the CJK flora since the late Neogene that have led to its current species richness.

N5-Modified alloxazinium salts including 5-ethyl-1,3-dimethylalloxazinium and 5-ethyl-1,3-dimethyl-8-(trifluoromethyl)alloxazinium salts were readily prepared as alloxazinium-resinsfrom the corresponding N5-unmodified ingredients via the aerobic oxidation—ion exchange protocol, previously introduced by us for the preparation of isoalloxazine analogues, and their catalysis and reusability in H2O2oxidations were evaluated.N5-Modified alloxazinium salts including 5-ethyl-1,3-dimethylalloxazinium and 5-ethyl-1,3-dimethyl-8-(trifluoromethyl)alloxazinium salts were successfully prepared as alloxazinium-resinsvia the aerobic oxidation—ion exchange protocol and demonstrated to be efficient and reusable organocatalysts for H2O2-mediated oxidations.

In tetraploids, inference of allelic dosages and inheritance modes is difficult due to the ambiguous number of allele copies and the variation between disomic and tetrasomic patterns. Considering the biases of amplification and the overlaps of stutter products in polymerase chain reactions, we inferred tetraploid genotypes at three nuclear microsatellite loci in progeny arrays from six reciprocal crosses among three parents of Betula apoiensis with a putative hybrid origin. In each cross, we assigned diploid genotypes to gametes on the basis of the tetraploid genotypes of the parents and their progeny and observed the frequencies of the gamete genotypes. Segregation patterns of the observed gamete genotypes indicated few null alleles in the progeny arrays and tetrasomic inheritance with rare double reduction. This mode of inheritance was consistent between genders and between mates in the crosses. This result suggests that our method to infer tetraploid genotypes in nuclear microsatellites is successful in family samples with few null alleles when the amplification biases and the stutter-product overlaps are accessed properly.

Abstract: To determine the lifespan of Siebold’s beech (Fagus crenata), a dominant canopy tree species of the cool temperate forests of Japan, we estimated the age of 33 mature beech trees felled by a large typhoon in September 2004 at Karibayama, in southern Hokkaido. The study site lies within one of the northernmost distributions of Siebold’s beech populations in Japan. We counted tree rings from tree disks at a height of 1 m, and diameter growth was measured in annual increments. The sample age revealed two major peaks at 240 and 175 years. The diameter growth was good between 40 and 60 years of age and gradually decreased after 70 years of age. Annual diameter increments were noticeably small in good fruiting years, indicating a large allocation of annual carbon gains to the reproductive organs. Bud scale counts of juvenile trees revealed that the age at which the height reached 1 m was approximately 6–13 years. The lifespan of Siebold’s beech in the Karibayama population was therefore estimated to be approximately 250 years, an estimation that is higher than that previously reported for this species in the northernmost populations.

AbstractTo determine the lifespan of Siebold's beech (Fagus crenata), a dominant canopy tree species of the cool temperate forests of Japan, we estimated the age of 33 mature beech trees felled by a large typhoon in September 2004 at Karibayama, in southern Hokkaido. The study site lies within one of the northernmost distributions of Siebold's beech populations in Japan. We counted tree rings from tree disks at a height of 1 m, and diameter growth was measured in annual increments. The sample age revealed two major peaks at 240 and 175 years. The diameter growth was good between 40 and 60 years of age and gradually decreased after 70 years of age. Annual diameter increments were noticeably small in good fruiting years, indicating a large allocation of annual carbon gains to the reproductive organs. Bud scale counts of juvenile trees revealed that the age at which the height reached 1 m was approximately 6–13 years. The lifespan of Siebold's beech in the Karibayama population was therefore estimated to be approximately 250 years, an estimation that is higher than that previously reported for this species in the northernmost populations.

Eupatorium: were examined by sequencing the internal transcribed spacers (ITS) of nuclear ribosomal DNA and restriction site analysis of chloroplast DNA. Molecular data provided strong evidence that (1) this genus originated in North America, (2) the genus diverged into three morphological species groups, Eutrochium, Traganthes and Uncasia in North America, and (3) one of the North American Uncasia lineages migrated into temperate Europe and eastern Asia over the Bering land bridge. The estimated divergence times support a late Miocene to early Pliocene migration from North America to Eurasia via the Bering land bridge. A European species was sister to all of the eastern Asian species examined. The disjunct distribution pattern of the genus Eupatorium is incongruent with the classical Arcto-Tertiary geoflora concept.

Abstract: The taxonomic status ofEupatorium chinese var.oppositofolium andE. glehni (=E. chinense subsp.sachalinense) inE. chinense complex semsu Kitamura has long been controversial. In this paper, the degree of divergence between diploids of these two taxa was examined by means of morphological studies including principal component analysis, the electrophoretic analysis of esterase isozyme variation and observations on habitats. The data obtained through the examinations indicate these two taxa are diverged enough to be recognized as distinct biological species. Since the polyploidE. chinense var.oppositifolium is more or less intermediate in morphology between the two diploid taxa, it is considered to have masked the distinction between the two diploid taxa. Also, electrophoretic evidence suggests that polyploidE. chinense var.oppositifolium is not a hybrid or hybrid derivative withE. glehni as a parental species. Possible origin of polyploidE. chinense varoppositifolium is also discussed.

Synthesis of methyl 5-azido-3-nitro-2,3,5-trideoxy-ß-d-glycero-pent-2-enofuranoside (7) from methyl 5-O-benzoyl-3-deoxy-3-nitro-ß-d-xylofuranoside (2) through five steps in 13% overall yield is described. The nitroolefin 7was treated with hydrazoic acid in the presence of trace of sodium azide, followed by hydrogenation and N-acetylation, to give a diastereoisomeric mixture of four triacetamido furanoside derivatives.

An electrophoretic study of isozyme number for seven soluble enzymes revealed extensive gene duplications in eight diploid species of American Eupatoriumbelonging to three morphological groups. The enzymes isocitrate dehydrogenase, phosphoglucomutase, phosphoglucose isomerase, 6‐phosphogluconate dehydrogenase, and shikimate dehydrogenase occur as three to six isozymes in all species, whereas the minimal conserved number typical of diploid plants is two isozymes for each. Fructose 1, 6‐biphosphate aldolase is expressed as multibanded pattern suggesting fixed heterozygosity in all examined species. It was not possible to document gene duplication for triosephosphate isomerase from the electrophoretic patterns. All species examined have a chromosome number of 2n= 20, which has been regarded as the basic diploid number for Eupatorium.However, the detection of extensive duplications suggests that 2n= 10 may be the original diploid chromosome number in Eupatoriumand that plants with 2n= 20 are of polyploid origin. This hypothesis would mean that extensive duplications at isozyme gene loci have been maintained since the origin of the genus, despite chromosomal diploidization having occurred.

Allozyme variation was investigated in 17 Japanese populations of Campanula punctata, ten from the Izu Islands and seven in the mainland (Honshu). The data indicate that there are two groups, a mainland group and an island one, and that the systematically problematic Oshima Island (northernmost Izu island) populations are closely related to those of the other islands. Nei's genetic identity values among islands and among mainland populations were 0.95 and 0.97, respectively, while the value between island and mainland populations was 0.84, suggesting that the island populations are an independent species. Total genetic variation was nearly the same among island and mainland populations. However, the apportionment of variation within and among populations was considerably different; 14% of gene diversity exists among mainland populations, while 31% of the diversity exists among island populations. Mean outcrossing rates of self‐incompatible mainland and Oshima populations are 0.62–0.79, supporting xenogamy; those in self‐compatible island populations are 0.37–0.57 in the northern islands, indicating a mixed mating system, and 0.16–0.25 in southern ones, indicating dominant inbreeding. Total genetic diversity in each island population decreased with distance from the mainland. Genetic and geological data suggest that the ancestors of insular populations were founded on northern islands in a relatively ancient period and that they dispersed progressively to the southern ones. Chromosome number (2n= 34) and isozyme numbers indicate gene duplications in this species, which suggests it is an ancient polyploid.

Arisaema serratum is a perennial herb capable of changing sex expression from year to year. We developed five polymorphic microsatellite markers for A. serratum to estimate male reproductive success. Variability at these loci was examined in two populations, one at Horigane and one at Kanazawa Japan; the number of alleles per locus ranged from five to 35 (the mean 21.4) in Horigane and from three to 36 (22.0) in Kanazawa. This high allelic diversity indicates that our markers are suitable for the study of male reproductive success in A. serratum.

Utilization of the spin Seebeck effect, a method for obtaining clean natural energy, is attracting more and more attention. We investigated the spin Seebeck voltage in relation to the saturation magnetization in yttrium iron garnet (YIG). We found that it is not proportional to saturation magnetization in YIG, indicating the existence of spin-current conductance in YIG. Pt/YIG samples with the same interface roughness and different structures exhibited different spin Seebeck voltages. The difference in the minimum YIG thicknesses for the saturation of the spin Seebeck voltage of Pt/YIG/gadolinium gallium garnet and Pt/YIG/sapphire structures was estimated on the basis of the relationship between the proportionality constant and the thickness dependence. The crystallinity of the YIG on these two substrates was investigated by X-ray diffraction spectrum observation. The spin-current conductance in Pt/YIG/substrates was found to be affected by the crystallinity of the YIG films.

The presence of diversity in the Stellera chamaejasmepopulation was found via their chemical composition. The eight collected samples were grouped into two chemotypes on the basis of the amount of neochamaejasmin B and chamaejasmine. Diversity was also found in the amount of afzelechin. The stereochemistry of neochamaejasmin B was confirmed by NOE experiment.

Five samples of four Saussureaspecies, S. hieracioides, S. stella, S. graminea, and S. tatsienensis, collected in Sichuan Province, China were studied and seven new diynes and a new alkene derivatives were isolated along with 16 known compounds. Absolute configurations of two of the new compounds were established using a modified Mosher's method.

Four Ligulariaindividuals possessing morphological characters of both L. nelumbifoliaand L. subspicatawere discovered in Shangrila County, Yunnan Province, China. DNA sequencing showed that the specimens were hybrids of the two species and their maternal parent was L. subspicata.The chemical composition of the root extract was examined for three of them as well as L. nelumbifoliaand L. subspicatacollected sympatrically. Nelumol was isolated from L. nelumbifolia, and furanoeremophilanes from L. subspicata. While nelumol and furanoeremophilanes were detected in two of the hybrid samples, only furanoeremophilanes were detected in the others.