Symposium Talks

Open symposium

OS-1 : The exibition "Plants and flowers that crossed the sea" and vegetation history in Japan
Sei-ichiro Tsuji*
(The University of Tokyo)
Temperate conifer forest or temperate conifer and broad-leaved mixed forests changed to a deciduous and evergreen broad-leaved forests ca.10000 years ago in Japan. The Black Stream (Kuroshio) became to approach the Japanese Archipelago, and its branch, the Tsushima Current, became to stream in the Sea of Japan, because sea level rapidly raised. The Black Stream brought many seeds and fruits from a tropic and subtropic regions to the Japanese Archipelago. Fruits of gourd and coconut excavated from archaeological sites of the Jomon Period dated ca.10000 years ago. During the Jomon Period, ca.10000 to 3000 years ago, Jomon people used several kinds of nuts of native trees as food. Many plants and flowers were intensively introduced to Japan from the Yayoi Period to the Ancient Age. In this stage, some grains such as rice and wheat, and some flowers such as chrysanthemum and poeny, with peach and Japanese apricot crossed the sea from China and Korea. Wetlands and hilly lands changed to mainly rice and wheat field by people activities. People deforested conifer forests such as cypress and Japanese cedar forests by iron tools. Many plants and flowers as vegetables and resources of spice crossed the sea from mainly China and South-East Asia from the middle to early modern Ages. Pine and oak secondary forests rapidly expanded in plane and low mountain areas. Tea tree also crossed the sea, and became to cultivate ca.1200 years ago. In the modern Age, many plants and flowers were directly introduced from Europe with Europeanization of life style. Many immigrants invaded mainly in plane areas, and drastically changed ecosystem.

OS-2 : A short review of Japanese horticulture: its remarks and history
Hideaki Ohba*
(The University of Tokyo)
Japan consists of numerous small islands off the east of the Asian continent climatically belonging to subtropical to subarctic. Especially the four main islands named Honshu, Hokkaido, Kyushu and Shikoku, have undulating complicated landscapes with mountains above 2000 m in elevations and variety of streams.
Peoples settled there have developed horticulture and cultivated a variety of plants for medicinal, vegetable and ornamental purposes. One of the remarkable features of the Japanese horticulture is that the boundaries of their habitation or estates have not rigidly established since the Jomon period. Except the yards they have understood that nature behind their habitation or estates is a part of gardens or the gardens are a part of nature.
More than 5000 species of flowering plants and ferns are indigenous to there. A great number of the species have been used for resources of various purposes. Japanese peoples have used numerous wild species for their cultivation, especially for medicinal and ornamental uses. Many shrubby plants with charming flowers, fruits or leaves like Camellia japonica, C. sasanqua, Pieris japonica, Kerria japonica, Aucuba japonica, Hydrangea macrophylla, Acer palmatum and allied species, and Magnolia stellata, now become international ornamental plants. Moreover, like the species of Lespedeza section Macrolespedeza, the group of flower cherries, Cerasus spp., Chloranthus spp., Miscanthus sinensis, numerous native species have been cultivated ornamentally. These species have hardly used for ornaments outside of Japan. Some indigenous species, like Rosa multiflora and R. luciae for the Polyantha and Wichuraiana groups of garden roses, Hosta spp., and Lilium auratum, L. speciosum, L. longiflorum for garden lilies, have become important resources to produce international ornamental plants.
Historically, horticulture might be established in Japan since the Jomon, Yayoi and Tumulus periods, however the realities are unclear because of the lack of documents. The Yamato and Heian periods were strongly influenced by Chinese cultures. The influence from China extends to Japanese horticulture especially ornamental purpose.
The Edo period, 1603--1867, is most remarkable in the horticultural history of Japan, and characterized by the advanced techniques to breeding and propagation, and by the large population to enjoy ornamental plants which extends toward the lower classes of the citizens of large cities like Edo, Kyoto and Osaka, and rich farmers in the country sides. For Japanese morning-glories, Ipomoea nil, the fanciers cultivated so-called ˇŌHenka-AsagaoˇÕ (mutant types) since early 19th century. For this the isolation of the recessive homozygous individuals, which are magnificent with deeply and irregularly incised corollas, are essential for ornamental purpose. This simultaneously requires to keep a large number the heterozygous and dominant homozygous individuals for the propagation because the recessive homozygous individuals are sterile. This technique established apparently earlier than the recognition of Mendelism. Breeders seem to catch genetically transposable elements and use for breeding of new garden forms. A great number of garden forms were produced in many ornamental plants like Psilotum nudum, Selaginella tamariscina, Pinus densiflora and P. thunbergii, Rodhea japonica, a variety of the species of Orchidaceae, Clematis, Paeonia suffruticosa and P. lactiflora, Anemone hepatica group, Adonis amurensis, Nandina domestica, Orostachys iwarenge, Cerasus spp., Acer spp., Rhododendron spp. (especially the Azarea group), Ardisia crenata, A. crispa, and A. japonica, Primula sieboldii, Dendranthema grandiflorum, and etc.
From the Meiji period, 1868--1912 to now, the horticulture of Japan has been received a great influence from Europe and other foreign countries, and gradually modernized.

OS-3 : Pedigree of melon (Coucumis melo L.) in ancient Japan
Noriyuki Fujishita*
(Osaka Prefectural University)
The oriental melon, Cucumis melo var. makuwa for sweet fruit and C. melo var. conomon for pickling, is the only vegetable having the oldest history of utilization and cultivation amongst the agricultural crops in Japan. Existence of a weedy momordica melon in Japan has never been recorded until 1980.
Even now a weedy melon, C. melo var. agrestis similar to the wild type, is distributed throughout 75 islands of Japan (1968-1981). They are found growing as a weed in or around fields of short crops, such as potato, penut, pepper, and soy been. Weedy melons have not been found in two archipelagoes, Nansei and Izu. The weedy melon has an egg shaped fruit,weight nangod between 5 and 50g at babitats.Its immature fruits are not eaten because of bitter taste. Fruits have been used as a toy and sometimes as ritual offerings. The weedy melon seems to be an ancertor of the oriental melon, because both melons can be crossed successfully and possess the same isozyme pattern and the same complementory genes concerned with the immature fruit bitterness. Maturity season ranged from late July to October.
To date the momordica melon, C. melo var. momordica, is cultivated in two islands, Hachijo and Fukue, far from the main island Honshu(1978). Seeds and fruits of the momordica melon are larger than those of the oriental melon. Flesh is extreme powdery and edible, but not sweet. Fruits have been used as food during the war.
A lot of melon seeds were excavated from 134 archaeological sites in Japan that ranged from 3rd B.C. to 19th century (1997). Seeds found from these sites revealed that the weedy melon and the oriental melon were used during the Yayoi Period ranging from the 3rd B.C. to the 3rd century A.D. Seeds of the momordica melon were found in the sites of government offices of the Nara and Heian Periods in 8th to 12th century A.D.
The weedy and momordica melons are one of the valuable genetic resources for future exploitation. Collection and preservation of these melons would be a duty of present scientists.

OS-4 : Genus Camellia in East Asia
Naotoshi Hakoda*
(Keisen University)
The original habitat of the genus Camellia L. (Theaceae) spreads from East to Southeast Asia, and about 250 species have been reported from this area so far.
1. In Japan lying at the northeastern tip of the distribution range of the genus, only three species (Camellia japonica L., C. sasanqua Thunb., C. lutchuensis T. Ito), one subspecies (C. japonica subsp. rusticana Kitam.), and one variety (C. japonica var. macrocarpa Massm.) grow naturally. However, a large part of ornamental Camellia cultivars cultivated in the world have been developed from three Japanese taxa, C. japonica, C. japonica subsp. rusticana, and C. sasanqua. Moreover, many natural hybrids, classified as C.x wabiske Makino, C.x vcrnalis Makino, C.x hiemalis Nakai, are found in Japan.
2 Southern China is considered as the center of origin of the genus Camellia. The genus Camellia and allied plants in this area were investigated in the 1960s to 1990s in great detail, and nearly 200 species have been reported.
In China, Camellias were important not just as ornamentals, but also as tea or oil plants, except for C. reticulata Lindl. of Yunnan and C. japonica of the east coast region.
3 Northern Vietnam is considered as the other center of origin of the genus Camellia besides south China, and yellow flowering species have been known to grow in this area since about a century ago. For a along time, however, scientific research on plants or animals could not be conducted because of continuous wars in this area. Since 1994, a large number of Camellia species including new, yellow flowering species have come to be reported from Vietnam by a joint research project consisting of Vietnam, French, and Japanese researchers.

Symposium 0: Open Lectures

S0-1 : Early angiosperms and their developmental stages in Northeast China
(Research Center of Paleontology, Jilin University, China)
The recent discoveries of the earliest known angiosperms represented by Archaefructus liaoningensis and A. sinensis from western Liaoning, China, revealed, in one aspect, the biotic evolutionary event took place in East Asia during the Late Jurassic. Archaefructus has simple and terminate axes bearing helical conduplicate carpels (follicles) enclosing several ovules(seeds) for each; the elongated adaxial stigmas extending over a large area on the carpels, and the stamens paired with monosulcate pollen. All the characteristics show a primitive characters of angiosperms. Current phylogenetic studies with combined multiple gene and morphologic analyses support the early angiosperm Archaefructus as the basal angiosperms and a sister taxon to extant flowering plants including the "ANITA" group. Archaefructus demonstrates herbaceous and aquatic nature, and its age is considered the Late Juassic, which is supported by the studies of its associated insects and the isotopic dating as 142.5±0.4 Ma and 147.3±0.3 Ma. Some dating results with younger ages would be considered that it might be affected by the factors caused by the volcanic activities after the deposits of the rocks in the western Liaoning areas. Four main developmental stages of the early angiosperms in Northeast China from Late Jurassic to early Late Cretaceous, are recognized, including (1)Jianshangou stage (Archaefructus assemblage, Late Jurassic) represented by Archaefructus and Hyrcantha*; and may by the possible angiosperm Beipiao; (2)Jixi stage (Asiatifolium-Xingxueina assemblage, perhaps Hauterivian-Barremian) represented by Asiatifolius,Jixia, Shenkuoa,Zhengia,Xingxueina, pollen in situ of Xingxueina and Clavatipollenites, evidenced in age by the marine beds yielding dinoflagellates Canningia pistica, Kiokansium polypes, Muderongia testudinaria, M. tetracantha, Palaeoperidium cretaceum; (3)Dalazi stage (Sapindopsis-Archimagnolia assemblage, Aptian-Albian) represented by Araliaephyllum obtusilobum, Archimagnolia rostrato-stylosa, Celastrophyllum sp., Eucommioides orientalis, Menispermites potomacensis, Sapindopsis magnifolia, Cf. Sassafras cretaceous var. heterolobum, Yanjiphyllum ellipticum, and pollen Clavatipollenites sp., Liliacidites dictyotus, Asteropollis sp., Singhipollis sp. Cupuliferoidaepollenites psilatus, Tricolpites micromunum, etc.;(4)Quantou stage (Platanus-Trapa assemblage, the latest Albian–Cenomanian) subdivided to two subassemblages, in which the early one characterized by Trapa angulata, Platanus septentrionalis, P. cuneifolia, Viburniphyllum serrulatum, Protophyllum undulatum; and the late one by Platanus sp., Dryophyllum subfalcatum,Schisandra durbudensis, Diospyros rotundifolia, Monocotylophyllum sp., and Saliciphyllum sp.

S0-2 : Molecular mechanisms in the evolution of land plant body plan
Mitsuyasu HASEBE*
(National Institute for Basic Biology, Okazaki, 444-8585, Japan)
Green plants landed more than 450 million years ago, and the basic body plan of land plants, the shoot system composed of a stem and leaves, was established in their early stage of evolution. To trace the origin and evolution of the molecular mechanisms of shoot system, homologues of the SHOOTMERISTEM LESS (STM) gene, which is a major regulator of shoot initiation and maintenance in flowering plants, were characterized in the fern Ceratopteris richardii and the moss Physcomitrella patens in addition to the assessment of polar auxin transport in the moss. Basic functions of STM and polar auxin transport are preserved among their diploid generation, although the moss does not form shoot-like structure in its diploid generation. This suggests that basal genetic tools for shoot system were established in the shoot-less common ancestor of land plants. On the other hand, STM expression and polar auxin transport were not detected in the haploid leafy-shoots of the moss, suggesting that diploid shoot systems of the vascular plants and haploid shoot systems of the moss evolved in parallel with different molecular mechanisms and that diploid shoots evolved with a de novo developmental system in stead of recruiting preexisted haploid shoot system.The flower is a reproductive organ of angiosperms. MADS-box genes mainly manage the development. We characterized MADS-box genes in the moss Physcomitrella and three charophycean green algae. These genes were specifically expressed in eggs and sperm during their differentiation, and the expression. These suggest that land plant MADS-box genes were originally involved in the differentiation of haploid reproductive cells, and then such haploid genes were recruited into a diploid generation. To assess whether MADS-box genes with such ancestral functions maintained in higher plants, expression analyses of 107 Arabidopsis MADS-box genes were performed. This revealed that several MADS-box genes are expressed in pollen with generative cells and likely maintain their original functions.

S0-3 : The importance of anagenesis as a phylogenetic pattern in plants of oceanic islands
( Department of Higher Plant Systematics and Evolution, Institute of Botany, University of Vienna, Rennweg 14, A-1030 Vienna, Austria)
Oceanic islands are outstanding laboratories for the study of plant evolution. Numerous morphological investigations over many decades, plus more recent molecular data, have revealed patterns and processes in different plant groups especially of the Bonin Islands, Canary Islands, the Hawaiian Islands, and the Juan Fernandez Islands. The classical pattern that has emerged from these studies is one of adaptive radiation being fundamental for generation of new species diversity. Recent investigations on Ullung Island, Korea, provide a dramatic contrast to this pattern by revealing no adaptive radiation. A comparison is made between patterns of phylogeny in the Juan Fernandez (Robinson Crusoe) Islands and Ullung Island. Previous studies in the former archipelago have revealed that cladogenesis (including anacladogenesis) accounts for only 29% of the specific diversity now seen. Perhaps surprisingly, the evolution of 71% of the endemic species can be explained by simple anagenetic (phyletic) change through geographic isolation, either from progenitors in the continent (Chile) or from another island. Ullung Island, located off the coast of N. Korea in the Eastern (Japan) Sea, extends this pattern to an extreme level. No example of intra-island cladogenesis is known, with most genera being represented by single endemic species. Anagenetic change, therefore, is seen as fundamental to explaining species diversity in both the Juan Fernandez archipelago and Ullung Island. The relative degrees of importance of cladogenesis and anagenesis for development of specific diversity in islands will vary depending upon geographical, geological, and ecological constraints, plus historical and biological factors associated with dispersal to and among the islands.

Symposium 1: Phylogeography: Molecular Approaches to Biogeography

S1-1 : Integrating phylogeny, fossil, and molecular dating in disjunct biogeography - determining migration route and time and unraveling post-isolation evolution
(jenny) Qiu-yun XIANG*
(Department of Botany, North Carolina State University)
Recent paleontological and molecular analyses have illuminated the origins of eastern Asian (EAS)-eastern North American (ENA) floristic disjunction and identified the Bering land bridge (BLB) and the North Atlantic bridge (NALB) as important routes for cross-continental plant migration. However, the relative roles of the two bridges during different geological time periods remain uncertain. Furthermore, subsequent diversification and evolution of the two floras after isolation is poorly understood. We integrated evidence from phylogeny, fossil, molecular dating, and dispersal-vicariance analysis to determine the migration routes and times involved in the disjunctions in Cornus. A robust phylogeny of the genus was reconstructed using sequences of four DNA regions. Molecular dating of the phylogeny was performed using combined DNA sequences employing penalized likelihood and Bayesian methods that do not require a molecular clock and allow implementing multiple fossil constraints. The dispersal-vicariance analysis incorporated fossil data to identify dispersal events and directions. The results suggested several intercontinental dispersals in Cornus, all appeared to originate in Europe and involve the NALB, although the timing varied from the earliest Tertiary to the Miocene. Our data support an important role of NALB in plant migration between Eurasia and America extending from the early Tertiary to the early Miocene. To gain insights into post-isolation evolution of disjunct taxa, we examined the rate of ITS evolution and species diversity in ten disjunct sister pairs from ten genera. The results revealed a general pattern of higher rate of ITS evolution and greater species diversity in the EAS counterparts, suggesting regional difference in net speciation and molecular evolution. A positive relationship between rates of ITS evolution and net species diversity found in the analysis further suggests the possibility of greater speciation rate in EAS facilitated by its heterogeneous topography and that speciation is likely linked to molecular changes in EAS and ENA.

S1-2 : Phylogeogarphy of Fatsia (Araliaceae) based on nucleotide diversity of trnD-trnT intergenic spacer and nuclear ribosomal ITS region
Shu-fang CHEN1, Kuo-hsiang HUNG1, Hidetoshi KATO2, Tsai-wen HSU1, Shann-jye MOORE3 and Tzen-yuh CHIANG*1
(1Department of Life Science, Cheng-Kung University, Tainan, Taiwan 701; 2Makino Herbarium, Tokyo Metropolitan University, Tokyo 192-0397, Japan; 3Department of Life Science, Taiwan Normal University, Taipei )
Fatsia, a genus of the Araliaceae, is endemic to the Archipelago of west Pacific Rim and Bonin Islands. These woody, perennial plants, with terminal inflorescence, are insect-pollinated. Drupaceous fruits attract birds for seed dispersal. Phylogeography of F. japonica (Japan), F. oligocarpella (Bonin), and F. polycarpa (Taiwan) was reconstructed based on nucleotide variation of cpDNA trnL-trnF intergenic spacer and nuclear ribosomal ITS region. ITS genealogy reveals a close phylogenic relationship between F. polycarpa and a haplotype of Okinawa, as well as between F. oligocarpella and a clade of Honshu and Ryukyus. Paraphyly of F. japonica indicates its ancestry. According to a molecular clock, the splitting of F. oligocarpella from F. japonica was dated to 1.35 million years before present, coinciding the divergence time for most endemic plants on the oceanic islands. Nevertheless, coalescence has not been attained at the cpDNA spacer within either species due to possession of shared ancestral polymorphisms. A very low level of genetic variation of cpDNA was detected in F. polycarpa, π = 0.00071, while genetic diversity was estimated at π = 0.00285 and π = 0.00282 in F. japonica and F. oligocarpella, respectively. Evidence of a close affinity to Oplopanax, a genus of North America and Japan, and natural habitats in mountainous areas in Taiwan suggests a likely temperate origin of Fatsia. Accordingly, F. polycarpa may have been founded in Taiwan via migrants from F. japonica, which possesses numerous genetic polymorphisms in both chloroplast and nuclear DNAs. This unusual, southward colonization was dated to some 700 thousand years before present. In contrast to the low genetic variation of cpDNA, postglacial demographic expansion, as indicated by significantly negative Tajima's D statistics, may have recovered the genetic diversity of the nrITS in F. polycarpa, which was estimated at π = 0.00327, a level comparable to that of F. japonica and F. oligocarpella. Very low levels of genetic differentiation were detected between populations within all taxa, although current, across-island gene flow is likely to be constrained. Phylogeographical analysis suggests that such low geographical structuring in Fatsia, like many plants of the archipelago, has been highly mediated by periodical glaciation.

S1-3 : Phylogeography of Japan: alpine plants and widely distributed plants in Japan
Noriyuki FUJII*
(Makino Herbarium, Tokyo Metropolitan University)
The Japanese Islands located in easternmost Asia contain more than 5000 species of vascular plants in spite of the islands relatively small area. From a phytogeographical view point, it has been generally considered that the Japanese flora were formed by the invasion of plant species from the Eurasian or Asian continents via Sakhalin Island, the Kuril Islands, the Korean Peninsula, and the Ryukyu Islands through out the past geological epochs. As evidence for this hypothesis, Japanese flora contain many widespread species that are also extant on the above-mentioned continents. On the other hand, it has been reported that about 40% of the plant species in Japan are endemic. This means that relatively many of the plants in Japan originated or have differentiated on the Japanese Archipelago. In order to understand the process of the establishment of Japanese flora, molecular phylogeographic studies have recently been performed by many botanists using various plant taxa. We have conducted phylogeographic studies using alpine plants (Pedicularis chamissonis and Primula cuneifolia, etc.) and plants widely distributed in Japan (Fagus crenata) based on the sequence data of chloroplast DNA (cpDNA). From these studies, we were able to find an interesting phylogeographic structure of cpDNA haplotype distribution. Based on analyses of alpine plants, an endemic clade distributed in the alpine region of central Honshu, Japan, has been inferred from phylogenetic analysis among the cpDNA haplotypes. These results suggest that there were refugia for Japanese alpine plants in central Honshu during the interglacial period. In F. crenata, on the other hand, we could recognize two major cpDNA clades: one is distributed mainly along the Japan Sea side of the Japanese Archipelago, while the other occurs chiefly along the Pacific Ocean side. A similar distribution pattern has been obtained from molecular phylogeographic analyses of other plant groups (Pedicularis gloriosa group, and Chrysosplenium macrostemon group, etc.). These results suggest that there were two migration routes (one along the Japan Sea and the other along the Pacific Ocean side of the Japanese Islands) in the evolutionary history of F. crenata or and other widely distributed plants in Japan.

S1-4 : Molecular population genetics and phylogeography of Japanese conifers
Yoshihiko TSUMURA*
(Forestry and Forest Products Research Institute)
The history of the evolution, changes in distribution and dissemination of species, populations and individuals is inscribed in their genomes. Therefore, when we carefully investigate their genomes, we can identify their origins and clarify details about their history. Genomic information has been accumulating for many plant species, especially commercially important ones such as crop and timber species. Cryptomeria japonica, is important forestry species in Japan and has provided valuable timber, for many purposes, since ancient times. Natural forests have been in decline due to over-exploitation and replaced by artificial populations. Natural forests of C. japonica have now become scattered and fragmented into small populations throughout its natural range. Several EST and mapping projects exploiting EST-based markers have been undertaken to analyze the sugi genome. Using the information obtained from linkage maps and EST-based co-dominant DNA markers, we investigated natural populations of C. japonica to clarify the genetic differentiation between populations. In previous studies using allozyme markers, no clear geographical cline of diversity was found. However, the genome-wide approach adopted here, using more than 100 mapped loci, allowed us to detect both a geographical cline and population differentiation of C. japonica. Two varieties, C. japonica and C. japonica var. radicans, are slightly but significantly differentiated and a single locus is strongly associated with this differentiation. Sequence variations at the corresponding locus did not appear to be related to the differentiation between the two varieties, suggesting that it may be attributable to a closely linked locus. We applied sequence tagged site (STS) markers derived from C. japonica to hinoki, Chamaecyparis obtusa, which belongs to the same family, Cuppresaceae sensu lato. One third of the STS markers derived from C. japonica yielded clearly amplified products in C. obtuse and thus were applied to natural populations of C. obtuse to investigate the genetic differentiation between them. Two clear tendencies were observed: the genetic diversity of marginal populations was relatively low and populations that were close to refugia in the last glacial period have higher genetic diversity than the others. I discuss here the phylogeography and population history of these two major Japanese conifers.

S1-5 : DNA polymorphism in structured populations
(Department of Biological Sciences, Graduate School of Science, The University of Tokyo)
Natural populations are often subdivided, and the subdivision might affect the pattern and amount of DNA polymorphism. In this talk I will discuss the effect of population structure on the pattern and amount of DNA polymorphism by using several models of population structure, including the two-subpopulation model, the finite island model and the finite stepping-stone model. The results suggest that the effect depends not only on the model used but also on the way of sampling. I will also examine the following case: an ancestral population was partially separated into two populations, and then, these two populations were isolated completely. The results suggest that both the migration rate between the two populations and the period of migration are important.

Symposium 2: Asian Plant Diversity and Floristic Research

S2-1 : Recent progress in the floristic research in Korea
Chong-wook PARK*
(School of Biological Sciences, Seoul National University, Seoul 151-742, Korea)
Korea is a peninsula on the far east coast of continental Asia. Physiographically, it is a mountainous peninsula extending southeast from the Manchurian mainland, and bounded on the north by the two rivers, Yalu and Tumen. Although Korea is relatively small in size, its flora is very rich and diverse in species composition because of its topographic and climatic complexities. Approximately 3159 species of vascular plants comprising 207 families and 1046 genera are known to be distributed in Korea. Also, there are a number of unique taxa that are endemic to Korea. Six genera are strictly confined to Korea; these include Mankyua (Ophioglossaceae), Megaleranthis (Ranunculaceae), Pentactina (Rosaceae), Echinosophora (Fabaceae), Abeliophyllum (Oleaceae), and Hanabusaya (Campanulaceae). The number of endemic species and varieties in this region is approximately 466. Phytogeographically, the Korean peninsula belongs to the eastern Asiatic floristic region of Takhtajan, in which its northern part belongs to Manchurian province and the remaining part to Japanese-Korean province; it has close floristic relationships with Japan and northeastern China including Manchuria, and occupies a vital position for the analysis and understanding of floristic patterns and relationships in eastern Asia. In particular, Korea shares a large number of taxa with Japan; all of 207 families, 91% of the genera, and 58% of the species found in Korea are also distributed in Japan. Despite its richness in flora, Korea as a whole received little taxonomic attention in the past. Several floras with varying quality and completeness have been provided by the Korean botanists since 1950s. They are, however, based on a very limited number of specimens and incomplete literature, because most of the important collections and the early literature in major Korean herbaria were destroyed during the Korean war. Consequently, many questionable taxa were included in these works without critical reevaluation, and treatments of many groups also need serious nomenclatural adjustments. Recently, we have initiated a 10-year project to produce a new Comprehensive Flora of Korea, which is funded by the Korean Government. The new flora will be written in English and published in eight volumes. The work will be entirely new and the descriptions and treatments will be specimen based, rather than extracted from the literature. Currently, 65 Korean botanists are involved in the project, and the first book in the series entitled "The Genera of Vascular Plants of Korea" will appear shortly in 2004.

S2-2 : Recent Progress in The Floristic Research in China
Jinshuang MA*
(Brooklyn Botanic Garden, Brooklyn, NY 11225-1099, USA)
Floristic works in China in the past ten years have been developed rapidly, especially on floras. Three different kinds of works are summarized here. First, Flora Reipublicae Popularis Sinicae (FRPS, Chinese edition) represents the largest floristic project in the world. The final product, 80 volumes in 126 parts, represents work by four generations of Chinese plant taxonomists over 40 years (1959-2004). The general aspects about the history, research team, contents and some comments on outline, timing, authorship, editors / authors, quality, concept of species, new taxa, specimens, statistics, largest taxa and conclusion of this monumental work are summarized. Second, Flora of China (FOC, English edition) started more than 10 years ago from the Missouri Botanical Garden, and cooperated world wide right now, has reached more than 40% at this time, and 10 volumes of 25 planned project have been published so far, plus 8 volumes of 25 Illustrations. The whole work will be done in less than 10 years as predicted. The general differences between the Chinese edition and English edition as well as their contents are summarized here for the first time, especially regarding the treatment of different taxa as well as their coverage.Third, local floras of China also gained very good progress at this time, and almost every province has their own floras among 31 provinces (Municipalities and Autonomous Regions), and most of them have been done very well, some even revised already. The whole pictures showed the great differences among different provinces, including the treatment of taxa, used systems, as well as their history, and development.

S2-3 : Plant Inventory Research: Contributions to the Flora of Myanmar
Nobuyuki TANAKA *
(The Kochi Prefectural Makino Botanical Garden)
Myanmar (Burma) is located south of the Himalayan region and, with a land area of 676,500 km2 (approximately twice the size of Japan), spans tropical evergreen, mixed deciduous, savanna and alpine vegetation types. With its wealth of plant diversity, Myanmar is one the most botanically fascinating countries in the world. However nearly half a century has elapsed since Kingdon-Ward, Unwin, Lace, Cooper and others conducted floristic surveys in the country, and much remains to be learnt of its flora as well as of its floristic relations with neighboring regions of Asia. Thus far, ca. 7,000 species of spermatophyte have been reported from Myanmar (Kress et al. 2003) though many more are likely to exist. In 2000, the Makino Botanical Garden, Japan, and the Ministry of Forestry, Myanmar, embarked on a collaborative inventory project for the plants of central Myanmar. Field studies have focused on 2 sites: i) Mt. Popa in Mandalay Division, an isolated in the dry zone (locally known as a green oasis); ii) Natma Tuang (Mt. Victoria) National Park in Chin State, which at 3,050 m is potentially rich in Himalayan and other Asian elements. A total of ten expeditions have been conducted with the cooperation of Botanical Gardens, the University of Tokyo. Our strategy in compiling a full Flora of Myanmar is to draw up inventories for each of the National Parks in the first instance. Checklists to the flowering plants of Mt. Popa and Mt. Victoria are currently being prepared based on the collections we have amassed so far. The Makino Botanical Garden has also organized training programs to help build capacity amongst our counterparts in Myanmar. Local botanists from the Myanmar Forest Department have been invited to Japan to broaden their knowledge of taxonomy and herbarium management. For the continued success of collaborative floristic work in Myanmar, a local research centre is required to serve as a herbarium and to promote education on issues such as conservation.

S2-4 : Diversity of pollination systems in Asian tropical rainforests
Shoko SAKAI*
(Center for Ecological Research, Kyoto University)
One of the most significant differences between pollination biology in the tropics and temperate forests is the rarity of abiotic pollination. The dominance of animal pollination reaches its extreme in lowland tropical rainforests, where no plant populations can be maintained without the assistance of animal pollen vectors. One major question in pollination ecology in the tropics is whether pollination systems in the tropics are more diverse than those in temperate regions, after considering the higher plant taxonomic and species diversity. There have been few attempts to compare pollinator fauna between temperate and tropical forests. Since hymenopteran and dipteran pollinators are not as dominant in tropical forests as they are in temperate ones, the diversity at higher taxonomic levels at least might be higher in the tropics. The other important question, which is in the context of conservation, is whether tropical plants have more specialized relationships with their pollinators than do temperate plants. Very specialized relationships, such as those between Ficus and fig wasps, ovule parasites of Ficus, have been found in some tropical plant groups, but the majority of plants have very "diffuse" relationships: a plant is pollinated by many species of animals and vice versa. However, pollination by parasites (pollinators that reproduce on or in the reproductive organs of plants) may be more common in the tropics.In comparison with the better-studied Neotropics, the most important factor molding pollination systems at the community level in the Sundaland region of Southeast Asia is "general flowering": mass flowering at the community level. In this region, the unusual single-family dominance of dipterocarps in the forest canopy has combined with the highly aseasonal climate to produce the phenomenon called general flowering, the synchronized flowering of most canopy trees and many others once every 2-10 years. This large fluctuation in floral resources may cause more plants in dipterocarp forests to be pollinated by social bees and fewer by large solitary bees, lepidopterans, and vertebrates. However, there is insufficient data for community-level comparisons of more seasonal vegetation types in Asia, which might provide more insights into the effects of seasonality on the pollinator community.

S2-5 : Tertiary evolution of the South East Asian megathermal flora in relation to tectonics and global climate change
Robert J MORLEY *
(School of Geography and Environmental Science, Monash University, Victoria 3800, Australia and Dept of Geology, Royal Holloway University, Egham, Surrey TW20 0EX, UK. Mailing address Palynova/PT Eksindo Prata)
The Southeast Asian region is geologically very complex and was created following the collision of continental fragments of Gondwana with the Asian and Pacific tectonic plates during the course of the Mesozoic and Tertiary periods. This overview focuses on the palynological record to highlight the main steps in the development of the flora of the region on a long geological time scale and within a plate tectonic framework. Following an assessment of the character of the region's flora at the beginning of the Tertiary (about 60 Ma), evidence is reviewed for the Eocene dispersal into the SE Asian region of diverse elements of the Indian flora following the collision of the Indian and Asian Plates (48 Ma). Many taxa that we consider typically Malesian today evolved on the Indian Plate and dispersed into SE Asia following this collision. Others initially radiated in Africa, dispersing to the Indian Plate as it drifted past Madagascar during the Cretaceous, and were subsequently rafted to Asia. The significance of Wallace's Line as a barrier to plant dispersal is then discussed particularly in the light of palynological records from the Tertiary of Sulawesi, from before the time of formation of the Makassar Straits. This is followed by an assessment of evidence for the immigration of Australian elements into the region following the mid-Tertiary collision of the Australian and Asian Plates (25 Ma), and of evidence for plant dispersal across Wallace's Line during the younger part of the Tertiary. Finally, a detailed climate history of the Sunda region is presented summarising the results of palynological analyses undertaken in two major hydrocarbon provinces. Firstly, the record is shown from the Natuna Sea (lat 5 degr N), that provides a picture of vegetation development in relation to climate change from the end Eocene (40 Ma) to mid Miocene (15 Ma). Secondly, newly acquired data from Indonesia's currently most active hydrocarbon exploration area in the Makassar Straits (lat 0 deg) will be presented for the first time, providing a comprehensive picture of climate change from about 15 Ma to the mid Pleistocene (about 1.5 Ma). Emphasis will be placed on the importance of alternating warm, everwet and cooler, seasonal/dry climates in moulding the flora. This database provides a unique insight into the long term history of rain forest refugia in the region.

S2-6 : Moss flora of Borneo, Universiti Malaysia Sabah
(Institute for Tropical Biology and Conservation)
The moss flora of Borneo was updated and consists of 724 taxa in 192 genera and 50 families. This shows an increase of 10% taxa since the last checklist of Borneon mosses by Touw in 1978. Sabah has 579 taxa in 177 genera and 48 families, showing an increase of 132 taxa since the last checklist. Sarawak has 307 taxa, an increase of 66 since Touw, in 85 genera and 28 families. Kalimantan has 270 taxa, an increase of 69 taxa, in 78 genera and 32 families, while Brunei has 36 taxa, an increase of 33 taxa, in 25 genera and 13 families. Mount Kinabalu, Crocker Range and Trus Madi of Sabah are better studied bryologically compared to other mountainous areas in Borneo. On the other hand, the central part of Borneo, a continuous range stretching from southern part of Sabah to western part of Kalimantan is almost unexplored bryologically. This area is proposed here to be studied bryologically due to threats of illegal logging and an interest to construct a transboundary road connecting Sabah and East Kalimantan.

Symposium 3: Molecular Phylogeny of Asian Plants

S3-1 : Origin and Evolution of "Plants" as Deduced from Genome Information
Hisayoshi NOZAKI*
(Department of Biological Sciences, Graduate School of Science, University of Tokyo)
Based on the recent hypothesis on the origin of eukaryotic phototrophs, red algae, green plants, and glaucophytes constitute the "primary photosynthetic eukaryotes" (whose plastids may have originated directly from a cyanobacterium-like prokaryote via primary endosymbiosis), whereas the plastids of other lineages of eukaryotic phototrophs appear to be the result of secondary endosymbiotic events (involving a phototrophic eukaryote and a host cell). However, phylogenetic relationships between the three lineages of the primary photosynthetic eukaryotes had remained unresolved because previous nuclear multigene phylogenies used the incomplete red algal gene sequences from the Rhodophyceae (one of the two lineages of the Rhodophyta) and lacked sequences from the Cyanidiophyceae (the other red algal lineage). We have determined complete nuclear genome sequences from the red alga Cyanidioschyzon merolae 10D of the Cyanidiophyceae (Matsuzaki et al. 2004, Nature). Using these genome information, we carried out nuclear multigene phylogeny of various lineages of only mitochondria-containing eukaryotes (Nozaki et al. 2003a, JME). Our phylogenetic analyses based on a 1525-amino-acid sequence of four concatenated nuclear genes (actin, elongation factor-1a, a-tubulin and b-tubulin) resolved the presence of two large robust monophyletic groups (Groups A and B) and the basal eukaryotic lineages (Amoebozoa). Group A corresponded to the Opisthokonta (Metazoa and Fungi), whereas Group B included various primary and secondary plastid-containing lineages (red algae, green plants, glaucophytes, euglenoids, heterokonts, and apicomplexans), Ciliophora, Kinetoplastida, and Heterolobosea. The red algae represented the most basal lineage within Group B. Therefore, the primary plastid endosymbiosis likely occurred once in the common ancestor of Group B, and the primary plastids were subsequently lost in the ancestor(s) of organisms which now lack primary plastids within group B. A new concept of "Plantae" is proposed for phototrophic and nonphototrophic organisms belonging to Group B, on the basis of the common history of the primary plastid endosymbiosis. This new scenario of the plastid evolution is discussed in comparison with genome information recently accumulated as well as our recent studies of a cladistic analysis of the "loss of plastid genes" (Nozaki et al. 2003b, JME) and phylogenetic analyses of nuclear genes of cyanobacterial origin (Nozaki et al. 2004, JME).

S3-2 : Cryptic species of the red alga Plocamium (Plocamiales, Rhodophyta) inferred from the molecular phylogeny and physiological properties
Mitsunobu KAMIYA*
(Fukui Prefectural University)
There are many organisms that are morphologically indistinguishable but are physiologically differentiated. Molecular phylogenetic analysis is useful to infer the evolution of such physiological features as well as to address the question whether they are genetically fixed or environmentally induced. We tried to clarify the diversity and evolutionary relationship of the Japanese Plocamium species on the basis of molecular phylogeny and physiological properties. Among five Plocamium species recognized in Japan, P. cartilagineum, P. recurvatum and P. telfairiae show similar blade morphology, and intermediates exist between them. Although there is no difference in their living thalli, the herbarium specimens of the Plocamium species demonstrate two different colors, blackish red (some specimens of P. recurvatum and P. telfairiae) and bright red (P. cartilagineum and the rest of P. recurvatum and P. telfairiae). The molecular analysis using Rubisco spacer and its flanking regions of rbcL and rbcS revealed that there are at least 13 haplotypes in the three species and some haplotypes show completely identical sequences to the other haplotypes of the different species. The distribution range is quite different among these haplotypes, and genetic distance of most haplotypes is not proportional to their geographic distances. In the molecular phylogenetic tree, these haplotypes were divided into two clades, which correspond to the thallus color of the herbarium specimens, not to the classification. Detailed investigation of Intracellular ionic concentrations by using pH meter and ion chromatography indicated that the blackish red specimens show significantly lower pH values and higher accumulation of Mg2+ and Br- than the bright red specimens. The stability of the Mg2+ and Br- accumulation was also demonstrated by the monthly ionic examination of P. telfairiae collected from the same population. These results suggest that thallus color of the herbarium specimens and intracellular ionic concentration, rather than conventional morphological traits, are informative and contribute to our understanding of the evolutionary relationship of the Japanese Plocamium species.

S3-3 : Major evolutionary advances in the history of green land plants
(University of Hamburg)
The insights provided by recent molecular studies both referring to the role of regulatory genes in plant ontogeny and phylogenetic reconstruction call for comparing them with the vast body of knowledge on extant and fossil plants within a broader evolutionary perspective, although many important phases of land plant evolution are only backed by the fossil record. The earliest land plants are represented by microfossils such as spore tetrads probably of hepatic affinity but in the Silurian plants similar to extant mosses appeared. The attribution of lignin, which imparted rigidity to water-conducting cells, made possible the evolutionary burst of tracheophytes. The early diversification of land plants that led to lycopsids, ferns and seed plants was accomplished by the end of the Devonian. Structural innovations such as the evolution of leaves and of cambia producing secondary wood and sometimes also secondary phloem and periderm appeared independently in various lineages. Relatively little is known about the appearance of roots and axillary branching, and the origin of the bipolar embryo, which is an attribute of the seed plants, remains completely obscure. Heterospory appeared independently in at least eleven different lineages in the mid-Devonian and Lower Carboniferous but remained bound to (semi-)aquatic environments until, in the seed plant lineage, delivery of the male gametophytes to the female permitted to fully exploit the land surface. Another corollary of heterospory and the acquisition of endospory was the compression of the dimorphic life cycle, in which the increasingly dominant sporophyte offered only a single target for selection. Gymnosperms dominated for about 200 million years, until, from the Mid Cretaceous onward, and particularly in the Tertiary, angiosperms took their part. More than anything else, their developmental flexibility and coevolutionary link with pollinating and seed dispersing animals must have contributed to their evolutionary success. Looking back over the history of green land plants it appears that major innovations were usually due to an interactive multitude of traits accumulated over longer periods and often arose several times in parallel and at different times.

S3-4 : Molecular phylogeny and morphological evolution of pteridophytes
Masahiro KATO*
(Department of Biological Sciences, Graduate School of Science, University of Tokyo)
Since 1994, one year later than the first most comprehensive analysis of angiosperm family molecular phylogeny (Chase et al. 1993), reports have been published for the molecular phylogeny of ferns and pteridophytes (Hasebe et al. 1994, 1995; Manhart 1995; Raubeson and Stein 1995; Pryer et al. 1995, 2001). They cover almost all families of pteridophytes, i.e. ferns and fern-allies. Surprising findings are close relationships of Psilotaceae (one of three fern-allies) and Ophioglossaceae, and of Equisetum (the second fern-ally) and Marattiaceae. Seed plants are sister to all those pteridophytes (Monilophytes). Earlier work had discovered that pteridophytes were diverged into microphyllous lycopods, the third fern-ally, and euphyllous plants, indicating that pteridophytes are paraphyletic. These phylogenies are in marked contrast to the traditional classification of pteridophytes into ferns and three fern-allies. Furthermore, the heterosporous water ferns, i.e. Azollaceae, Marsileaceae, and Salviniaceae, are monophyletic, although they are morphologically divergent and the heterospory and aquatic life have been considered as a result of convergence. The tree ferns (Cyatheaceae, Dicksoniaceae and Metaxyaceae) are monophyletic. Polypodiaceae, a higher epiphytic family, are sister to Davalliaceae, another epiphytic family. The molecular phylogeny proposed is consistent with the suggested morphological evolution in some lineages, but disagrees so remarkably in others as not to explain with ease. Consistency is seen in the basal groups. The microphyllous lycopods and euphyllous pteridophytes differ in the leaf, root, soral position and dehiscence. The basal euphyllous pteridophytes, though paraphyletic, comprise eusporangiate groups, and Osmunda links them with leptosporangiate ferns. Psilotaceae and Ophioglossaceae differ in that the former lack roots and the latter have unique megaphyllous leaves. Equisetum and Marattiaceae also differ in the leaf architecture. In Equisetum the vegetative leaves are whorled stenophylls at nodes and the reproductive leaves are peltate sporangiophores gathered in a separate strobilus. In Marattiaceae the fertile leaves are megaphylls with sori on the lower surface. The inconsistency may imply that the euphyllous leaves, including seed plant leaves, evolved recurrently in multiple lineages. The evolution of the root is still uncertain.

S3-5 : Molecular phylogeny of conifers and family diversification: review and perspective
Shu-miaw CHAW*
(Institute of Botany, Academia Sinica, Taipei 115, TAIWAN)
Conifers, the largest group among living gymnosperms, comprise seven to nine families and over 600 species. In the past decade substantial progress has been made in understanding the molecular phylogeny of the seed plants, but whether Taxaceae and Gnetales may be viewed as extremely divergent conifers, remain intensely debated subjects. Investigation on the genes relevant to key gymnospermous characters may contribute to resolve these debates. The distribution of conifer families has long been known to be remarkably uneven in both hemispheres. Moreover, majority of the relic or endemic genera of the Cephalotaxaceae, Pinaceae and Taxaceae, centers on the east and west of the Pacific (Li, 1953). The origin, age, and diversification of conifer families inferred from fossil data are still contradictory to limited earlier molecular phylogenies. In this study diversification and ages of living conifer families were assessed by phylogenetic analysis of new nuclear and chloroplast datasets from over 70 gymnosperm taxa. Implications will be presented and discussed with integrated information from past geography and new fossil data.

S3-6 : Molecular phylogeny of Angiosperms
Hiroshi TOBE*
(Department of Botany, Graduate School of Sciences, Kyoto University)
Molecular data obtained from plastid and nuclear DNA sequences have greatly contributed to understanding an overall picture of evolution and relationships in angiosperms. The relationships do not appear to be much different from what had been outlined mainly on the basis of morphological evidence until 1980s. However, a significant progress has been made by molecular phylogenetic analyses, for example, in finding the most basally positioned taxa (Amborella and Acorus) in angiosperm and monocot evolution. It also has raised further questions as to which of their morphological features are plesiomorphies or apomorphies ? On the other hand, the molecular analyses have still remained some major plant groups unresolved with respect to their in-group relationships. Such plant groups include Ericales, Lamiales, Malpighiales, and Saxifragales. While providing a review of the progress of the current molecular studies for angiosperm phylogeny, we present some topics of morphological studies of Amborella and Acorus and results of our ongoing molecular study of Malpighiales.Malpighiales are a large group of 25-37 families. Our analyses based on sequence data of 18S rDNA, atpB, rbcL, and matK genes using 238 genera in 20 families emphasizing genera of the traditionally circumscribed Euphorbiaceae (sensu Webster) resulted in 37 most parsimonious trees. Their strict consensus tree showed that nearly all of the families were distributed in dichotomously branched clades even if not all of the clades were strongly supported. Notably Euphorbiaceae were restricted to three subfamilies "Acalyphoideae", "Crotonoideae" and "Euphorbioideae," but several genera such as Chaetocarpus, Trigonostemon and Pogonophora in "Acalyphoideae" were placed in the most basal position and sister to the rest of the family. The latter group is characterized by developing the palisadal exotegmen in mature seed coat. Several other embryological characters such as the thickness of the inner integument and the presence or absence of vascular bundles in the integuments are also likely to support some major clades that are not always supported by high bootstrap values. When properly combined, evidence from morphology (anatomy) and molecular data is very likely to provide a resolution for relationships in Malpighiales and the other orders.

Symposium 4: Informatics in Plant Systematics

S4-1 : SEABCIN (South East Asian Botanical Collections Information Network)
Leng Guan SAW*1 and Denis FILER2
(1Forest Research Institute Malaysia; 2Department of Plant Sciences, University of Oxford )
The South East Asian Botanical Collections Information Network (SEABCIN) is a project that will bring together data on plant diversity contained in databases in South East Asia and Europe and make them available worldwide for query and analysis. The project involved seven herbaria in South East Asia and two institutions in Europe; Herbarium Bogoriense, Indonesia, Forest Research Institute Malaysia, Kepong, Malaysia, Sabah Forest Department, Sandakan, Malaysia, Sarawak Forest Department, Kuching (Malaysia), Philippine National Herbarium, Manila, the Philippines, Singapore Botanic Gardens, Singapore and Forest Herbarium, Royal Forest Department, Bangkok (Thailand) and in Europe; National Herbarium Netherlands, Leiden, Netherlands and Plant Sciences Department, University of Oxford, UK. A central web-based database will be established with sharable and standard lists relevant to the region, for species, geographical information, collectors and other key dictionaries. Data for these dictionaries were primarily developed from herbarium specimens. The first phase of the project will run for 3 years from 2001 and will end in 2004. For this pilot project, a few plant groups were selected as pilot project for the web-based database, these are one family (Dipterocarpaceae) and 7 genera (Alocasia, Alpinia, Cinnamomum, Dracaena, Goniothalamus, Lindera and Paraboea). About 70,000 records from the partner herbaria are currently available on the web.

S4-2 : Indonesia Biodiversity Information System (IBIS). Case Study: Vegetation Diversity of Bangka Island, Bangka-Biliton, Indonesia
(Biodiversity Information Centre, Research Centre for Biology, LIPI)
Indonesia Biodiversity Information System (IBIS) is a system developed by Research Centre for Biology, LIPI dedicated for Indonesian biodiversity data management. This system is comprises some applications that user can easily conducted retrieval data and then exported to other file (spreadsheet, word, other textual or spatial databases) for further analyses. More than 2,000 records of herbarium data from Bangka Island have been entered to this system. Base on that data more than 49 families comprises, 230 genera and 550 species has been manages by this system. This data has generally collected during Dutch Colonial occupy Indonesia. New data has collected intensively since 2000 collaborated between LIPI and local government of Bangka to investigate the total biodiversity data after mining activities finished. Bangka islands is also called as "Tin Island" and become very famous area due to the tin mining. Preliminary vegetation study has been conducted to monitor the species that still survive in this area. This paper will discuss about species the flora diversity includes vegetation type occurs in this area, as a basic data for environmental recovery and reclamation program after tin mining activities finished.

S4-3 : Integration of local flora information in Asia
Motomi ITO*
(Department of Systems Sciences, The University of Tokyo)
Although we recognize the great competence of the IPNI project, we still find a large gap in its coverage of names between regions, particularly in Asian plants. Thus, developing a regional system for providing an Asian vascular plant name service and collecting plant names in this region are urgent issues. Our project aims to develop a fundamental regional hub system for providing names of vascular plants in East Asia. This will cover the scientific names and synonyms qualified by experts in East Asia, including vernacular names. As the first step, we collected scientific and vernacular names appearing in Flora of Japan Database (, which is a digitalized version of the latest edition of Flora of Japan, edited by K. Iwatsuki et al. We ported the records of FOJ to Nomencurator, a new data model for taxonomic name database, proposed by Nozomi Ytow. The concept of Nomencurator makes it possible to provide multiple taxonomic views, and we intend to apply it to Asian flora, for integrating local checklist of Asian countries. Nomencurator model requires name appearance; a set of name, publication and taxonomic annotation. Thus, we define three types in taxonomic annotation; accepted name, synonym, and original description. We input these name appearance in synonymic lists, as well as accepted names. Now, we are working to converting Taiwanese and Korean plant checklist to this system, for integrating the flora with different name usages.

S4-4 : Taxon name and taxon cconept
Nozomi YTOW*
(University of Tsukuba)
Several taxonomic database models supporting multiple hierarchical structureshave been proposed, and some of them have been implemented.The distinction between name and taxon concept, however, is not well understood.A taxon concept is best considered as the glue that binds together the members of that taxon. It is inseparable from the name that it carries, which serves as the vehicle for communication about the grouped members. The members bound by the taxon concept, however, can be removed or added as taxonomists understanding increases.A name is often considered to be a label attached to an object. This model works well with concrete objects, such as herbarium sheets, and attachment and detachment of the label (changing the name) does not affect the essence of the object. The object, for instance the herbarium sheet, may also carry another label bearing the collection number or specimen identifier that is unique to that particular specimen. This label cannot be changed because it is specific to the specimen, not to the group within which the specimen is included, i.e. the taxon concept. These two types of label can be confused.The heart of the problem with taxon concepts is finding an adequate definition: it is closely related to trying to define a species. Taxon concepts are reflected in character-state lists that can only be locally complete, over the domain of known specimens, never globally complete, over all possible specimens. The taxon concept is also represented by an ostensive definition, i.e. by a list of examples known to be included. The challenge for a taxonomic database is to be able to decide whether two taxon concepts are equivalent (effectively identical).Hierachies are built by organisation of instances defined by taxon concepts. Various authors propose hierarchies that may be compatible or incompatible, but to compare the hierarchies it is necessary to align equivalent taxon concepts. As a first approximation, this can be achieved by aligning names and looking for incongurance. Absence of incongruance suggests that the taxon concepts are at least compatible if not equivalent.

Symposium 5: Species in a Variety of Plant Groups

S5-1 : The Changing Species Concepts of Mosses
Benito C TAN*
(Department of Biological Sciences, National University of Singapore)
The bryophytes are the most diverse group of land plants next to the flowering plants and occupy a basal phylogenetic position in the embryophyte radiation. These primitive land plants have a number of important biological differences from the other plant groups, which include: (1)nearly equally well-developed sporophytic and gametophytic phases in their life cycle; (2)extensive phenotypic plasticity; and (3)heavy reliance on asexual reproduction. These differences have made the recognition of natural biological species in bryophytes difficult because of the uncoordinated evolutionary trends seen between the gametophyte and sporophyte. Historically, the species definition of mosses has switched back and forth a number of times between an emphasis more on the gametophytic characters or more on the sporophytic characters. With the advent of molecular evidence, the definition of a species based on molecular characters may not be in support of the species definition based on macro characters. Although recent advances in cladistic programs allow a combined and objective analysis of both haploid and diploid characters, in addition to the molecular characters, still, a satisfactorily defined natural biological species in mosses remains a daunting task.

S5-2 : Genetic diversity in apogamous fern species of Dryopteris erythrosora group (Dryopteridaceae)
(Graduate School of Science and Technology, Chiba University)
Vascular plant species have generally been described based on morphological characters. Whereas efforts have also been made to recognize species which reflect the biological entity such as biological species. Pteridophytes have less morphological characters useful for identification than seed plants do. Therefore it is very likely that morphologically defined species of pteridophytes include multiple biological species (Murakami & Yatabe 1999). However, about 10% of pteridophytes are characterized by a kind of asexual reproduction called apogamy. Biological species concept cannot be applied to them. Then how should we realize the biological entity of apogamous pteridophytes? A naturally existing unit superior to an individual in apogamous taxa is probably "a group of individuals derived asexually from one ancestral plant" or "a clone". Thus the method of detecting the biological entity of apogamous species should be distinguishing or identifying clones. Allozyme analyses have been managed for this purpose and most of examined apogamous species were revealed to include more than one electrophoretic variants (Lin et al. 1995, Ishikawa et al. 2003). One simple interpretation is that each variant is a clone originated independently. More complicated one is that there are some phylogenetic relationships among variants. In apogamous species, some behaviors which partly resembles sexual reproduction have been observed, such as hybridization with sexual species (Walker 1960), unequal meiosis (Lin et al. 1992), and genotype segregation through homoeologous chromosome pairing (Ishikawa et al. 2003). Of course there are fundamental opportunities of mutations. Then some of electrophoretic variants might derived from the same ancestor. The difference may be only one mutation. If so, relationships among variants are not equivalent, and they can be categorized into some groups according to their origin. Analysis using nuclear DNAs has a potential to clarify the relationships among variants. Phylogenetic relationships among alleles cannot be verified in allozyme analysis. PCR-SSCP analysis using nuclear genes can distinguish SSCP variants. Moreover relationships among variants can be examined by constructing phylogenetic trees of alleles. DNA-based investigations should promote more detailed understanding of the biological entity of apogamous species.

S5-3 : Hybrid speciation of a high mountain pine Pinus densata
Xiao-ru WANG*
(Institute of Botany, Chinese Academy of Sciences, 100093 Beijing, China)
Habitat divergence plays a crucial role in plant speciation, especially in diploid or homoploid hybrid speciation. In contrast to polyploidy, diploid hybrid speciation is rare due to the possibility of backcrossing to the parental species. Divergence in a new ecological niche or colonization of a novel habitat may lead to reproductive isolation after the initial hybridization, thus, leading to speciation process. One example of diploid hybrid speciation supporting this hypothesis is the evolution of Pinus densata. This pine is native to southwestern China and Tibet and grows at high elevations (2700 – 4000 m asl), where neither of the two parents can normally grow. At these elevations, P. densata regenerates well and forms huge areas of pure forest. Allozyme, cpDNA and mtDNA data testify the origin of P. densata through hybridization between P. tabuliformis and P. yunnanensis. Genetic composition and parentage orientation varies among P. densata populations. These data suggest complex evolutionary histories among P. densata populations. Cytogenetic analysis of the hybrid genome indicated certain chromosomal rearrangements. The speciation of P. densata is hypothesized to be related to the uplift of Tibetan plateau. The unique territory created by the uplift of the plateau would have facilitated the development and stabilization of the hybrid. It is difficult to distinguish among traits that facilitate habitat divergence in the hybrid lineages. Our ongoing project on the QTL mapping combined with molecular cytogenetics analysis should provide more answers in revealing the adaptation mechanisms of the hybrid. In addition, gene genealogies can be used to measure the evolutionary processes of selection, migration and drift that are involved in the speciation of this hybrid pine.

S5-4 : Seasonal and ecological factors as isolation mechanisms between species of the genus Heloniopsis (Monocotyledonae: Melanthiaceae)
Shizuka FUSE*
(Museum of Nature and Human Activities, Hyogo, Japan)
Heloniopsis (7 spp.) is evergreen insect-pollinated perennial herbs, distributed in East Asia. In this study, I investigated four populations in Shikoku and Kinki Districts, Japan, where H. breviscapa and H. orientalis grow sympatrically / parapatrically, focusing especially on how the two species are isolated. In Kochi population in Shikoku, the flowering peak of H. breviscapa was earlier than that of H. orientalis by about one month in 2002 to 2004, and the flowering periods of the two species were not overlapped with about one week gap. Results of morphological and microsatellite DNA analyses do not show any traces of gene flow between H. breviscapa and H. orientalis in the Kochi population, although cross experiments between the two species yield fruits with viable seeds. Seasonal factors are suggested as a major barrier between H. breviscapa and H. orientalis in the Kochi population. In Hyogo population in Kinki, the flowering periods of H. breviscapa and H. orientalis were overlapped in 2002 to 2004, although the flowering peak of the former was earlier than that of the latter by about two weeks. Results of morphological and cpDNA analyses show about 45% flowering individuals of the Hyogo population as hybrids. The Hyogo population is located more or less in natural environments, including rich soils in humus, rocks along a stream, and the intermediates. No flowering individuals of H. breviscapa grow at the rich soils in humus, and no flowering individuals of H. orientalis grow on rocks along a stream. The hybrids often grow at the intermediate conditions. This suggests that ecological factors such as soil conditions are important in inhibiting H. breviscapa and H. orientalis from being totally mixed. In two Nara populations in Kinki, which are located in anthropogenic environments of Cryptomeria plantation, all the flowering individuals investigated proved to be hybrids between H. breviscapa and H. orientalis based on results of morphological and cpDNA analyses. This confirms ecological factors as important in isolation between H. breviscapa and H. orientalis in the populations in Kinki, and when natural environments are disturbed, the two species are sometimes totally mixed.

S5-5 : Facultative agamospermy and introgressive hybridization in Taraxacum (dandelions) species complex
Ki-joong KIM*
(School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea)
Facultative agamospermy and introgressive hybridization in Taraxacum (dandelions) species complex Ki-Joong KimSchool of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea (e-mail: Taraxacum officinale complex was introduced from Europe to Korea about a hundred years ago. This species complex occur widely on Korean peninsula and took over the habitats of native species of Taraxacum and increasingly common in open habitats. Taraxacum officinale complex produce more abundant agamospermous seeds than native species, however, some populations also show facultative sexual reproduction. Native species of Taraxacum consist of diploids, triploids, and tetraploids and show a series of facultative sexual reproduction. In order to measure the degree of gene flow between native and introduced species, we analyzed the maternally inherited chloroplast DNA markers (RFLP patterns and nucleotide sequences of trnL-F regions) and biparentally inherited nuclear markers (ITS sequences) from 600 individuals (86 populations) in the Korean peninsula. Nuclear ITS trees show the morphologically circumscribed species boundaries both in native and introduced species. However, the cpDNA trees are substantially different from that of nuclear rDNA and show mixed patterns between European and Korean species. Hybridizations are most commonly observed between the introduced species and the facultative apomitic native species. The results also suggest that the introgressive hybridization from introduced species into native species (or vs.) is one of major driving force to the emergence of successful invasive populations and to the extinction of native populations.

S5-6 : Selection and speciation: exploring the origins of wild sunflowers
Briana GROSS* and Loren H RIESEBERG
(Indiana University, Bloomington, Indiana, USA)
How important are deterministic and stochastic forces in the speciation process? Do chance events or selective pressures govern the patterns of diversity found in nature? Through the application of phylogenetic and quantitative genetic techniques, we have shown that deterministic forces likely played an important role in the origin of three homoploid hybrid species of wild sunflower. The three species, Helianthus anomalus, H. paradoxus, and H. deserticola are all derived from hybridization between the two parental species H. annuus and H. petiolaris. Phylogenetic patterns suggest that two of the species, Helianthus anomalus and H. deserticola, may have multiple origins, and thus be the product of many parallel speciation events. Phenotypic selection analyses show that habitat mediated selection acting on early generation hybrids between the parental species favors traits that are characteristic of modern H. deserticola and H. paradoxus. Finally, QTL analyses indicate that selection on individual loci controlling traits under selection may be strong enough to allow the neospecies to divergence even in the face of continuing gene flow with the parental species.