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Abstracts Sunniva Aagaard Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, Department of Biology, Museum, N-7491 Trondheim, Norway Poster — Secondary hybrid zones are not uncommon in Dactylorhiza, but rigorous studies have rarely been undertaken. The main aim of this study is to describe the hybrid D. incarnata ssp. cruenta x D. lapponica (2n=3x=60) and its parent taxa with morphological and isozyme markers and to assess interploidal gene flow. The analysed material of 270 individuals was collected from one allopatric D. incarnata ssp. cruenta (2n=2x=40) population, one allopatric D. lapponica population (2n=2x=80) and two populations were the species were found in parapatry. Photometric quantification of DNA was performed on 59 individuals, of which 16 were found to be diploid, 12 triploid and 31 tetraploid. D. lapponica is a segmental allotetraploid resulting from pairing between homoeologous chromosomes, whereas D. incarnata ssp. cruenta is monomorphic at the four loci investigated. The unbalanced banding patterns observed in tetraploids means that triploids could not be identified solely on the basis of isozyme banding interpretation. Incidents of introgression and homoeologous pairing were found to be indistinguishable, since no variation was observed in the diploid parent species. Discriminant analyses of morphological data showed that the parent species were not more similar in the parapatric populations compared to when they occur in allopatry. This either indicates that introgression has not occurred, or that the populations are not isolated enough to prevent gene flow. Molecular diagnostics at and below the species level Konrad Bachmann Department of Taxonomy, Institut für Pflanzengenetik und Kulturpflanzenforschung, IPK Gatersleben, D-06466 Gatersleben, Germany Invited talk — The identification of plant genetic resources at and below the species level is increasingly becoming a matter of public interest. Questions of the physical or intellectual ownership and the geographical origin of plant species, varieties or cultivars can have considerable consequences and may lead to legal disputes which require an accurate identification based on objective criteria. The material in question may not be a complete plant, but a part such as a fruit, seed, or dried leaf material. Many of these plants will be the products of plant breeding involving recombination, induced mutations, or genetic transformation. The traditional approach to identification which requires individual training and familiarity with the characters of use in each separate group of plants will not be able to keep pace with these increasing demands. While this approach will remain indispensable for the characterization of biological diversity, a new approach will be needed for identification providing access to all of the relevant information about a plant. Since all heritable characters are eventually encoded in the genome, and character differences will be reflected by sequence polymorphisms, methods based on the identification and interpretation of sequence polymorphisms may provide a general and reliable way to identify plants. Moreover, these methods will be universal and standardized, and they can be applied by technical personnel with a general training in basic methods. The success of this approach will depend on the selection and interpretation of relevant sequence polymorphisms. Random markers from throughout the genome (RAPD, AFLP) have provided quick and easy access to subspecific genetic structuring , but for technical and theoretical reasons it is not possible to convert these analytical data directly into diagnostic applications. This is different for individually characterized microsatellite loci, but eventually single nucleotide polymorphisms (SNP) appear to be the ultimate marker system for the development of diagnostic methods. Efforts are underway to find SNP patterns corresponding to recognized taxa and to link SNP patterns with relevant information on phylogeny, morphology and physiology. The enormous amount of research required to reach the necessary level of informativeness and reliability for all plants is justified for four reasons: (1) the method is likely to provide the definitive access to biodiversty information, (2) the data will be universal and cumulative, (3) much relevant information will be obtained as a by-product of other molecular research, and (3) the data will be compatible with any formal representation of taxonomic relationships. Practical aspects to be discussed will be methods of SNP detection and problems in the correlation of SNP patterns with biologically relevant data. Characterization of angiosperm nrDNA polymorphism: paralogy and pseudogenes C. Donovan Bailey1, Colin E. Hughes1, Stephen A. Harris1 & Timothy G. Carr2 1Department of Plant Sciences,
University of Oxford, Oxford, OX1 3RB, UK Talk — Nuclear ribosomal DNA (nrDNA) internal transcribed spacer region sequences (ITS 1, 5.8S, and ITS 2) have been a staple source of data for the study of lower level phylogenetic relationships among plant taxa for more than ten years. Many early reports of ITS variation were consistent with homogeneous nrDNA arrays within individuals. However, some older and more recent studies have identified the occurrence of intra-individual nrDNA polymorphism across a range of taxa including presumed non-hybrid diploids, suggesting that complete concerted evolution should not be assumed when embarking on phylogenetic studies using nrDNA sequences. Furthermore, it is clear that polymorphic individuals often contain potentially non-functional nrDNA copies (pseudogenes) in addition to functional copies. Putatively functional and non-functional sequences have generally been referred to as paralogs and a variety of techniques have been used to distinguish these two classes. Here we review species-tree reconstruction when faced with nrDNA polymorphism. In doing so, we attempt to clarify nrDNA paralogy in relation to the functional/nonfunctional classes of sequences. We examine the various definitions and characterizations of nrDNA pseudogenes as well as the relative merits and limitations of a subset of pseudogene detection methods. Finally, we present and discuss the advantages of a tree-based approach to distinguish pseudogenes based on comparisons of sequence substitution patterns from putatively conserved (e.g., 5.8S) and less constrained (e.g., ITS 1 and ITS 2) regions. Freek T. Bakker1, Elizabeth M. Marais2, Tasoula Touloumenidou3, Priyani Hettiarachi4, Alastair Culham5 & Mary Gibby6 1Nationaal Herbarium Nederland,
Wageningen University branch, Generaal Foulkesweg 37, 6703 BL Wageningen, The Netherlands Invited talk — Phylogenetic hypotheses for
the largely South African genus Pelargonium L'Hér. (Geraniaceae) were derived
based on DNA sequence data from nuclear, chloroplast and mitochondrial encoded regions. A
single hypothesis synthesising the information in the three data sets was constructed for
149 species. Pelargonium, a characteristic element of the Cape Floristic Region,
was found to consist of five main clades, structured in two (subgeneric) clades that
correlate with chromosome size. Contrasting evolutionary strategies and speciation modes
among these clades can be inferred based on patterns of population size, biogeographic
distributions and dispersal capacity, pollination biology and karyological
diversification. Detecting and visualizing reticulate patterns in molecular data Hans-Jürgen Bandelt Fachbereich Mathematik, Universität Hamburg, 20146 Hamburg, Germany Invited talk - Tree-building techniques often give only little insight into the structure of a set of (homologous or paralogous) DNA sequences, especially when the data are far from constituting a perfect phylogeny. A whole array of statistical tests are available that aim at signalising reticulate patterns that would e.g. emerge through recombination (Posada 2002). It is however not safe to rely on a single family of tests and to reach far-flung conclusions without a detailed exploration of the data that seeks to detect anomalies and reconstruct their potential causes. There is certainly a lesson to learn from human mitochondrial DNA: a Science paper (that turned out to be the canard of the year) claimed that there was evidence that human mtDNA would recombine (Awadalla et al. 1999). This analysis, was based on a patently unsuitable linkage disequilibrium measure and an inappropriate test scenario employing only a tiny portion of the published data. This notwithstanding, several papers in the field actually presented data with a few instances of “recombination”, which however were never noticed by the authors. Such data sets are notoriously flawed for several reasons: e.g. sample contamination, PCR artefacts (phantom mutations), artificial recombination of non-contiguous stretches of DNA, and poor reading and documentation of sequencing outputs (Bandelt et al. 2000, 2001, 2002). In most cases a thorough explorative analysis contrasting the particular data with the total database would have pinpointed to the reticulate patterns and the increased level of homoplasy. Analysis of incompatibilities of the full data matrix (or of certain submatrices) is one of the basic tools: e.g. Jakobsen & Easteal (1996) assessed incompatibilities of sites and confront the resulting pattern with the linear order of sites in the molecule. As is well known, pairwise compatibility is insufficient to guarantee a perfect phylogeny when the characters are not binary. The concept of strong compatibility introduced by Dress et al. (1997) circumvents this problem (at the expense that perfect phylogenies may harbour characters that are not strongly compatible). Moreover, a number of features of the full quasi-median network representing a particular data submatrix can directly be read off from pairwise strong compatibility of the participating characters. Systematics of Grusonia Reichenbach ex Britton & Rose (Opuntioideae: Cactaceae) Rolando T. Bárcenas & Julie A. Hawkins Centre for Plant Diversity and Systematics, School of Plant Sciences, The University of Reading, Reading, RG6 6AS, UK Poster — The genus Grusonia has
undergone recent changes in its taxonomy to comprise approximately 19 species of
opuntioids of the North American deserts of Mexico and the United States. Grusonia
is a morphologically heterogeneous group of low to medium sized mat and clump-forming
opuntioids. They are characterised by the clavate, ovate, or cylindric stems, the more or
less flattened spines with bulbous bases, and the rudimentary papery-sheaths covering the
tips of the spines. Internal Transcribed Spacer sequence diversity in two species of Asteraceae Nigel P. Barker1, Seranne Howis1 & Inge von Senger1,2 1Molecular Systematics Facility,
Department of Botany, Rhodes University, Grahamstown, 6140, South Africa Talk — The Internal Transcribed Spacer (ITS)
region of over 50 samples each of Chromolaena odorata and Chrysanthemoides
monilifera have been obtained. Both these species are invasive weeds in various parts
of the world. Chromolaena odorata is indigenous to Central and South America and
the Greater Antilles, but is a major invasive in southern Africa and elsewhere in the
world. Chrysanthemoides is indigenous to southern Africa, but is an invasive in
Australia. These two species have very different dispersal systems, but little is known
about the finer points of their reproductive biology. The causes of speciation in plant lineages Timothy G. Barraclough1 & Gail Reeves2 1Department of Biological Sciences,
Imperial College at Silwood Park, Ascot, Berkshire SL5 7PY, UK Invited talk — Species-level phylogenetic trees reconstructed from molecular data can be used to test hypotheses about the timing and causes of diversification. We demonstrate this approach using a dated DNA sequence tree for South African Proteaceae. First, we use well-established methods to compare alternative models of the temporal dynamics of speciation and extinction. The results highlight the need for care in interpreting the apparent timing of speciation from dated trees. Second, we investigate the role of ecological and geographical factors in promoting speciation in the region. We discuss the strengths and weaknesses of species-level data for studies of speciation. Modes, rates and mechanisms of local genomic change in the Poaceae Jeffrey L. Bennetzen Department of Biological Sciences and Genetics Program, Purdue University, West Lafayette, IN 47907-1392 USA Invited talk — Analyses of several thousand kb of genomic DNA sequence that we have generated for comparable regions of the maize, sorghum, rice, barley, wheat, and pearl millet genomes have indicated that local genomic rearrangements are orders of magnitude more frequent than rearrangements that can be detected by comparative recombinational maps. Duplications, deletions, inversions and translocations of small genic segments are common, but are mostly without a known mechanism. Some genomes, like that of maize, appear to be particularly unstable. Rice and sorghum, on the other hand, show good relative conservation of gene order and content in compared chromosomal segments. Even within a stable genome, some genomic regions can be quite unstable, for instance around orthologous Wx loci and in R gene clusters. In several cases, we have been able to gather evidence that suggests the molecular mechanisms of some of these changes in local genome structure. Unequal homologous recombination and illegitimate recombination are appear to be major players in many rearrangement events. Further studies are needed to determine whether these mechanisms of instability are equally influential in all grass lineages, but preliminary studies indicate that all of the mechanisms are at least present in each grass species studied. Further investigations will determine the effects, if any, these changes have upon gene and genome function. At this point, we can only conclude that local genome structure is highly dynamic in the grasses. Polyploid speciation in wild potatoes (Solanum sect. Petota) Ronald van den Berg Nationaal Herbarium Nederland, Wageningen University branch, Generaal Foulkesweg 37, 6703 BL Wageningen, The Netherlands Talk — The wild relatives of the potato (Solanum sect. Petota) comprise a group of about 200 tuber-bearing Solanum species. Polyploidy is rather common in the group with, besides a majority of diploid species, also triploids, tetraploids, pentaploids and hexaploids. Most of the polyploids are hypothesized to be allopolyploids, originated through hybridization. Hybridization hypotheses abound in sect. Petota, mostly inferred from morphological and cytological data. A few cases have been tested with synthetic hybrids and/or molecular data. The evolutionary history of sect. Petota and, indeed, the origin of the (tetraploid) cultivated potato, is by and large a tale of the development of polyploid species (groups). Unravelling the composition of polyploid genomes has become feasible using molecular data and advanced cytogenetic tools like genome in situ hybridization (GISH). Islands in an arid world – investigations on populations of Gibbaeum cryptopodium (Aizoaceae) Gisela Bertram & Ute Schmiedel Botanical Institute, University of Hamburg, Ohnhorststraße 18, 22609 Hamburg, Germany Poster — Quartz-fields of the Succulent
Karoo in South Africa offer a prime model for the study of isolated island-like
populations within an arid environment. Schmiedel & Jürgens (1999) showed that
isolated azonal quartz gravel fields represent islands which are much different from the
surrounding matrix vegetation with regard to plant communities, abiotic conditions and
growth forms of the plants. Schmiedel, U. & N. Jürgens. 1999. Community structure on unusual habitat islands: quartz-fields in the Succulent Karoo, South Africa. Plant Ecology 142: 57–69 Speciation patterns of Peperomia in Polynesia Una Bradley1 & Steve Waldren2 1Department of Botany, Trinity
College, Dublin 2, Ireland Talk — The remote islands of South-eastern
Polynesia (defined here by the Pitcairn Islands, the Islands of French Polynesia and the
southern Cook Islands) provide an ideal environment in which to base an evolutionary
study. In South-eastern Polynesia there are 17 species within the genus Peperomia,
14 of which are endemic. Sculpture pattern of wing petals in legumes of the eastern ghats of south India S. John Britto Centre for Natural Resources Study, Department of Botany, St. Joseph’s College, Tiruchirapalli-620 002, India Talk — The floral biology of legumes is vast and relatively complex. There is a need for a re synthesis of our knowledge about the reproductive biology of legumes, not only for its application in systematics but also to clarify other aspects like species to species relationship, phylogeny and others. In recent times characters pertaining to floral biology in legumes hitherto either neglected or unused are found to possess systematic value and have wider applications at every level of taxonomic hierarchy. Sculpture pattern of wing petals in legumes, so far neglected and unused has proved valuable in establishing generic and specific delimitations. Sculpture or the ephemeral folds on the outer surface of the wing petals are a widespread feature, showing constancy within the group on the one hand and separability from others, on the other. Their function and the extent of their occurrence in different tribes need further investigation. The present paper describes the sculpture patterns of some legumes using different cytochemical, morphological and fluorescent analyses, which exhibit specific variations among them. Nuclear DNA content variation of Eleocharis palustris agg. in Europe Petr Bureš, Lucie Horová & Sierra Dawn Stoneberg Holt Department of Botany, Faculty of Science, Masaryk University, Kotlá_ská 2, CZ-611 37 Brno, Czech Republic Poster - Following morphological
measurements and chromosomal counts, carried out on native populations in Austria,
Bulgaria, Croatia, the Czech Republic, Denmark, Estonia, Germany, Hungary, Ireland, Italy,
Lithuania, Luxembourg, the Netherlands, Norway, Portugal, Rumania, Slovakia, Slovenia,
Spain, Sweden and Switzerland, which confirmed six taxa within the Eleocharis palustris
agg. in Europe (Bureš 1998, 1999, 2002), we have focused on the study of relative DNA
content variability of these taxa using DAPI flow cytometry. Bureš P. (1998): A high polyploid Eleocharis
uniglumis s. l. (Cyperaceae) from the Central and Southeastern Europe.
– Folia Geobot., 33: 429–439. Evolution of Convolvulus L. in the Mediterranean and Macaronesia Mark Carine Department of Botany, The Natural History Museum, Cromwell Road, London SW7 5BD United Kingdom Talk - Convolvulus L. (Convolvulaceae) comprises more than 200 species worldwide, with the greatest diversity found in the Mediterranean, Macaronesia and the Middle East. Within Macaronesia, a wide range of growth forms are found including lianas, erect shrubs and dwarf spiny shrublets. Of the 16 native species recorded from the region, ten are endemic to the Canary Islands and one is endemic to the Madeiran archipelago. Webb (1844) described a separate genus, Rhodorhiza, for those species endemic to Macaronesia. In contrast, Sa’ad (1967) placed the Macaronesian endemic lianas, shrubs and spiny shrublets in three different subsections within Convolvulus and more recently, Mendoza-Huer (1983) suggested that there are two distinct groups of Macaronesian endemics. As part of a broader systematic study of Convolvulus, a molecular phylogenetic study of the Macaroneisan and Western Mediterranean species is currently in progress utilizing data from the the ITS region of nrDNA and trnL-F region of cpDNA. The results of this work are presented and their implications for our understanding of the evolution of Convolvulus in Macaronesia and for the classification of the genus more widely are discussed. Hybridisation and Introgression in Mediterranean Senecio (Asteraceae) Mark A. Chapman & Richard J. Abbott Sir Harold Mitchell Building, School of Biology, University of St. Andrews, St. Andrews, Fife KY16 9TH, Scotland Poster — The distribution of nuclear (RAPD)
and cytoplasmic (cpDNA RFLP) molecular markers throughout the Mediterranean ranges of Senecio
gallicus, S. glaucus and S. leucanthemifolius have been studied in an
attempt to determine the ancestry of two populations of Senecio found on the south
coast of Sicily. Mark W. Chase1, Richard Bateman2 & Michael F. Fay1 1Jodrell Laboratory, Royal Botanic
Gardens, Kew, Richmond, Surrey TW9 3DS, UK Invited talk — We have been studying how allopolyploids have evolved in two distantly related groups of angiosperms, Dactylorhiza (Orchidaceae) and Nicotiana (Solanaceae), the former poorly characterised and the latter well understood using ‘traditional’ approaches. In the case of Dactylorhiza we have been employing a mixture of genetic approaches to determine what are the parents and at what ploidy levels have the hybrids been produced: DNA sequencing of plastid regions and nuclear ribosomal ITS as well as plastid and nuclear microsatellites and AFLPs. It is clear that allopolyploids have arisen a number of times from different parents, both diploids and tetraploids, but the patterns are so complex that a great deal of additional work is required before direct comparisons can be made to other groups in which this process has occurred. Nicotiana, conversely, has been well characterised, particularly by the work of Goodspeed (1940–1950s), and although he did not correctly identify all parents of allopolyploids correctly, it is clear that hybridisation involved only diploids and the allopolyploids have not crossed with either their parents or each other. In fact, the parental diploids and their polyploid offspring often occupy distant areas (for example South America for the parents of N. section Suaveolentes, which are found now only in Australia and Africa). Although allopolyploids have been formed multiple times, their ancestries have been relatively easily determined. Partly this is due to the circumstances in which hybridisation has occurred and partly due to the fact that Nicotiana is easily cultivated, which facilitates cytological studies, whereas at least some of the taxa involved in allopolyploidy in Dactylorhiza are difficult to maintain outside their native environments. In both cases, parental taxa are not particularly closely related within the context of their respective genera, a factor that may be related to why these taxa show such frequent allopolyploidy. Species-level phylogenetics in Neotropical Annonaceae Lars W. Chatrou1, Michael D. Pirie1, Roy H. J. Erkens1, Timo van der Niet1, Johan B. Mols2, and Jan W. Maas1 1 Nationaal Herbarium Nederland,
Utrecht University Branch, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands Invited talk - Neotropical representatives of the Annonaceae, a pantropical family of trees and lianas, have been a major focus of systematic research at the Utrecht branch of the National Herbarium of the Netherlands since the founding of the international Annonaceae project 17 years ago. Extensive revisionary work and the accumulation of numerous new collections has been complemented in recent years by the building of a phylogeny of the family as a whole. Despite the difficulty of adequately sampling with respect to species level phylogeny reconstruction, sufficient material has been collected to resolve species-level phylogenies of a number of Neotropical genera. We present results on the following three genera: Cremastosperma (ca. 35 spp., 30 of which are included in our analysis ), Duguetia (100 spp., 35 of which are included), and Guatteria (ca. 250 spp., 50 of which are included). For each of the genera phylogenies are presented on the basis of the following cpDNA markers: rbcL, trnT-L intergenic spacer, trnL intron, , trnL-F intergenic spacer, psbA-trnH intergenic spacer, and partial matK. The three phylogenies are reviewed in the context of the family phylogeny of the Annonaceae. With the exception of a few basal lineages, the majority of the ca. 2500 species of the family diverge into two major sister clades, distinct on the basis of pollen morphology, geographic distribution, and patterns of molecular evolution. Of these two clades, one is characterised by inaperturate pollen and has an apparent rate of molecular divergence (revealed by branch lengths in most parsimonious trees) about three times as high as the other clade, characterised by monosulcate and disulculate pollen. Duguetia and Guatteria are in the long-branch-clade, Cremastosperma is in the short-branch-clade. The repercussions and implications of this phenomenon will be discussed. So Yean Cho, Keum Ryon Ze, Jong Pill Lee, Joo Young Park, Sang Yong Park, Young Ja Jung, Chang Hee Cho, Kwang Won Ha Division of Herbal Medicine Standardization, Korea Food and Drug Administration, Korea Cnidium Rhizome is a frequently prescribed herbal medicine in Korea, Japan as well as China,which has been successfully used in these countries for the treatment of diseases related to gynecology, blood circulation and dental troubles. And it is circulated as the same chinese character, although original plants are different as Cnidium officinale in Republic of Korea or Japan and Ligusticum chuanxiong Hort. in China. A lot of herbal medicines are imported from China and it is very difficult to distinguish a Cnidium officinale Makino from a Ligusticum chuanxiong by organic or physicochemical experiments. In this report, PCR-mediated RFLP method using ITS primers and restriction enzymes such as Hae III, Nla IV, Apo I, Eco RV, Sma I and Mbo II was given a trial to identify origin of these herbal medicines. The ITS regions of nuclear ribosomal DNA were analyzed to determine original plants and to design a molecular identification method for the herbal medicine in Republic of Korea, Japan and China. Speciation by hybridization in European orchids: evidence by nuclear and chloroplastic markers Rossella Cianchi, Maria Cristina Mosco & Luciano Bullini Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza’, Via dei Sardi 70, I-00185 Rome, Italy Talk — A number of hybrid species has been recently detected in orchids of the genus Dacylorhiza, by the use of codominant single copy nuclear markers (e.g. enzyme loci). They differ in ploidy level, mode of reproduction, genetic variation and single versus multiple origin. The Allotetraploid Marsh Orchids (D. elata s.l.) show sexual reproduction and have 4x=80; their parental species are D. saccifera s.l. (2n=40) and D. incarnata s.l. (2n=40), as suggested on chromosome basis by Heslop-Harrison (1953, 1954, 1957) and assessed on allozyme basis (Hedrén, 1996a, b; Bullini et al., 2002). Genetic comparison of various AMO taxa from Europe and Caucasus showed their multiple origin, both in time and space; the maternal species was generally D. saccifera s.l., as shown by cpDNA. Other hybrid Dactylorhiza species are allotriploid and reproduce by apomixis. Among marsh orchids, four triploid apomictic taxa, as yet undescribed, have been evidenced: three of them show 2 genomes from D. incarnata and 1 from D. saccifera, the fourth has 2 saccifera and 1 incarnata genomes. Their origin from occasionally fertile backcrosses of AMOs with either parental species has been suggested; according to the taxon, cpDNA was contributed from either D. saccifera or D. incarnata (Bullini et al., in press). The Western Mediterranean orchid D. insularis (3x=60) shows sporophytic polyembriony; this species derived from hybridization between D. romana (2n=40) and D. sambucina (2n=40), which contributed two and one genomes, respectively, as assessed by allozyme markers; the maternal species was D. romana. D. insularis had a single, recent origin and shows limited clonal variation (Bullini et al., 2001). Genetic relationships between Dactylorhiza hybrid taxa and their parental species, as inferred from cpDNA, are generally similar to those reported for nuclear ribosomal intergenic spacer (ITS; Bateman et al., 1997; Bateman, 2001). These findings suggest that concerted evolution, i.e. homogenization towards one parental species, has occurred in hybrid Dactylorhiza taxa at ITS level, highly biased towards the maternal parent. When a phylogenetic tree is not a phylogeny - allopolyploidy in Nicotiana (Solanaceae) James J. Clarkson1, Sandra Knapp2 & Mark W. Chase1 1Jodrell Laboratory, Royal Botanic
Gardens, Kew, Richmond, Surrey TW9 3DS, United Kingdom Talk — The origins of the amphidiploid taxa in Nicotiana (Solanaceae; about 70 species) have recently been illuminated using the technique of genomic in situ hybridisation (GISH). These have arisen from crosses that are sometimes ‘wide’ (distantly related) and in other cases more ‘narrow’. Parsimony analysis produced almost complete species-level trees from both plastid and nuclear ribosomal regions. Due to a lack of variability large regions of DNA from the plastid genome were sequenced (matK, trnL-F, ndhF and trnS-G). The internal transcribed spacer (ITS) region of ribosomal DNA constituted the second dataset. When compared the two analyses showed the same basic patterns. However the positions of the amphidiploids differed. Due to gene conversion, these hybrid taxa did not produce hybrid ITS sequences. Most had ITS types that were consistent with their maternal parent (e.g. N. rustica) but some like their paternal parent (eg. N. tabacum). Neither dataset can reliably be used to reveal hybrids, and in some cases hybrids appear in the same positions (i.e. they are not incongruent in the plastid and nuclear trees), which could lead unsuspecting researchers to conclude they are not hybrids. Dispersal and speciation in Mediterranean Senecio Max Coleman1, Aaron Liston2, Joachim Kadereit3 & Richard Abbott1 1Division of Environmental and
Evolutionary Biology, School of Biology, University of St Andrews, St Andrews, Fife, KY16
9TH, UK Talk — Phylogenetic analysis of Old and New World Senecio sect. Senecio was performed to explore the biogeographic history of Mediterranean/arid plant disjunctions. Phylogenies based on internal transcribed spacer (ITS) sequences of nrDNA revealed a well-supported clade corresponding to sect. Senecio. Area optimization indicated this to be of southern African origin. The Mediterranean and southern Africa were not distinguishable as sources of the main New World lineage, estimated to have become established during the Mid-Pliocene. Another previously suspected recent dispersal to the New World from the Mediterranean was confirmed for the recently recognized disjunction in S. mohavensis. The loss of suitable land connections by the Miocene, means that both New World lineages must represent long-distance dispersal, providing the first evidence of repeat intercontinental dispersal in a Mediterranean group. In contrast, migration within Africa may have utilized an East African arid corridor. Recent dispersal to northern Africa was supported for S. flavus, which formed part of a distinct southern African lineage. Novel pappus modifications in both disjunct species may have enabled dispersal by birds. An estimated Early Pliocene origin of sect. Senecio coincides with the appearance of summer-dry climate. However, diversification from 1.6 Mya highlights the importance of Pleistocene climate fluctuations for speciation. Helena C. Cotrim1, M. Salomé Pais1, Mark W. Chase2 & Michael F. Fay2 1Laboratory of Plant Biotechnology,
ICAT, Ed. ICAT, Campo Grande, P-1749-016 Lisboa, Portugal Poster — Ophrys (Orchidaceae) is a
genus of more than one hundred species, mostly native to Europe with a concentration of
species around the Mediterranean. The genus is well delimited, but infrageneric
relationships are not clear. The monophyly of the genus contrasts with species
relationships within Ophrys that are generally poorly resolved probably a
reflection of controversial, morphologically-based classifications. Recent publications
indicated 142 ‘species’ in Europe with a great number of narrow geographic
species and subspecies. This situation is yet more complex as a result of the great number
of hybrids described between sympatric species. Hybridisation is putatively common in Ophrys
with at least 100 hybrids having been reported. Recent literature supports a well-resolved
monophyletic group containing O. bombyliflora, O. speculum, O.
tenthredinifera and an O. fusca-lutea lineage. Ophrys has eight species
in Portugal (O. apifera, O. bombyliflora, O. fusca, O. lutea, O.
scolopax, O. speculum, O. vernixia, and O. tenthredinifera). Apomixis, occasional sex, hybridisation; what’s happening with Sorbus? Robyn S. Cowan1, Tim C. G. Rich2 & Michael F. Fay1 1Royal Botanic Gardens, Kew, Richmond,
Surrey TW9 3DS, UK Poster — In the British Isles, the genus Sorbus
is represented by about 25 taxa, 15 of which are endemic, often with very narrow
distributions. There are four diploid (2n=34) sexual species, S. aria (whitebeam), S.
aucuparia (rowan), S. domestica (true service tree) and S. torminalis
(wild service tree), and the remainder of the species are largely apomictic, which are
either triploid or tetraploid (2n=51,68). Research of chloroplast DNA markers by PCR-RFLP in the genus Dactylorhiza (Orchidaceae) Nicolas Devos, Anne-Laure Jacquemart, Daniel Tyteca & Renate A. Wesselingh Unité d’Écologie et de Biogéographie, Biodiversity Research Center, Université Catholique de Louvain, Croix du Sud, 4-5, 1348 Louvain-la-Neuve, Belgium Poster — The genus Dactylorhiza
consists of many species restricted to Northwest Europe. Members of this genus are
morphologically variable and their taxonomic status is not very well defined. In the wild,
species can be found in sympatry and hybrids are currently observed. If hybridisation and
introgression are commonly observed in the genus, some species could have a recent origin. Constraints in the radiation of apomicts Peter van Dijk Netherlands Institute of Ecology (NIE-CTO), Heteren, The Netherlands Invited talk — Apomixis is the production of
asexual seeds, genetically identical to the mother plant. Apomictic lineages are
reproductively isolated from sexual and other asexual lineages. Variation in apomictic
taxa is very obvious and has led to the recognition of hundreds of microspecies (e.g. Rubus,
Taraxacum, Hieracium). Apomixis is relatively rare in the plant kingdom.
Although reported in more than 400 species, it occurs in only 0.1 per cent of the
angiosperms. Lenka Drábková1, Jan Kirschner1, Cestmír Vlcek2, Ole Seberg3 and Gitte Petersen3 1Institute of Botany, Academy of
Sciences, Zámek 1, 252 43 Pr_honice, Czech Republic Talk — Phylogenetic analyses derived from
plastome rbcL and trnL intron and trnL-trnF intergenic spacer
were performed to examine relationships among taxa representing most of subgenera and
sections of Luzula and Juncus (excl. sect. Forskalina and sect. Caespitosi)
Juncaceae. Taxa were chosen to reflect morphological and geographical diversity of both
genera. The most important conclusions concerning the phylogeny of Juncaceae were: (1)
high support for the major clade (99% jackknife) comprising Luzula sections, (2)
the resolution of highly supported subg. Juncus (98% jackknife) excluding a part of
sect. Graminifolii and sect. Juncus, (3) the position of J. capensis and
J. lomatophylus as a sister group to the remaining small juncaceous South
Hemisphere genera, (4) separate position of sect. Juncus (a clade comprising J.
maritimus and J. kraussii). Morphological and genetical identity of Rhinanthus individuals in mixed populations Véronique Ducarme & Renate A. Wesselingh Université catholique de Louvain, Biodiversity Research Centre, Unité d'Écologie et de Biogéographie, Croix du Sud 4-5, 1348 Louvain-la-Neuve, Belgium Poster — The principal goal of this project
is to study the origin and the dynamics through time of natural hybridization between two
annual plants Rhinanthus minor and Rhinanthus angustifolius (Scrophulariaceae).
The occurrence of hybrids between these species and their flower morphology was largely
documented by Kwak (1978). In our study, we will correlate flower morphology with
individual genetic identity. Thus, we will be able to track introgression events even when
hybrid flower morphology has become indistinguishable from that of pure species. Jointly,
we will study the mechanisms of reproductive isolation between these species in order to
explain the direction of introgression. A Macaronesian fern in Portugal: relictual or introduced? Cecília Durăes1, 3, Stephen J. Russell2, Frederick J. Rumsey2, Mary Gibby3, Fátima Sales4, Johannes C. Vogel2 1Institute of Ecology and Resource
Management, University of Edinburgh, Darwin Building, Mayfield Road, Edinburgh, EH9 3JU,
UK Poster — Asplenium hemionitis L. is a diploid fern distributed on all Macaronesian archipelagos, with scattered outlying populations in northern Africa and only one site in mainland Europe, near Sintra, Portugal. The fossil record shows it was present in Europe during the Tertiary. A. hemionitis was first discovered in Sintra in the 17th century, but a recent survey revealed that extant populations are now confined to man-made walls in a Moorish castle complex. We employed allozyme electrophoresis to a) determine the prevailing breeding system, b) assess genetic variation within and between populations, c) establish whether the populations at Sintra can be regarded as autochthonous relictual populations of this Macaronesian element and d) make recommendations regarding the conservation of the species. Identification of Gaharu (Aquilaria and Gyrinops) dry wood samples using trnL-trnF polymorphisms Marcel C.M. Eurlings & Barbara Gravendeel Nationaal Herbarium Nederland, Universiteit Leiden branch, P.O. Box 9514, 2300 RA Leiden, The Netherlands Talk — Gaharu is a fragrant resin in the wood of Southeast Asian tree species in the Thymelaeaceae family that develops after fungal infection. Production is recorded from several species of the genera Aquilaria, Gyrinops, Gonystylus and Phaleria. Gaharu is of high economic importance in Asia due to its use for the production of incense and traditional medicines. It is ranked among the most highly valuable traded forest products worldwide. High prices have stimulated intensive gaharu harvesting and eight Aquilaria species have declined to such an extent over the last decades that they were placed on the IUCN Red List Category. The most threatened species, A. malaccensis was even placed on CITES Appendix II in order to control international trade to avoid extinction. As gaharu is mostly traded as wood chips, accurate monotoring of trade in A. malaccensis is seriously hampered as identification to species level is impossible by conventional microscopy. The CITES Plants Committee therefore financed a pilot study on the development of DNA identification tools. DNA was isolated from recent and up to a 90-years old herbarium and dry wood samples of different Aquilaria and Gyrinops species. Gaharu samples bought at local markets in Papua New Guinea were also included. The plastid trnL-trnF intergenic spacer region was successfully amplified from several of these samples using specially developed primers. After sequencing, several polymorphisms useful to distinguish species and geographical origin of the samples were found. Phylogenetic analyses of the sequences obtained indicate that species of Aquilaria and Gyrinops are intermixed in one monophyletic group. These findings indicate that both genera should be merged and that the single morphological character separating them (a different number of stamens) does not reflect evolutionary relationships. Patrizia Famŕ1, Brian Wysor2, Wiebe H. C. F. Kooistra3 and Giuseppe C. Zuccarello4 1Laboratoire de Systématique
Moléculaire, Département de Zoologie et Biologie Animale, Université de Genčve, 1224
Chęne-Bougeries, Switzerland Talk — The genus Caulerpa consists of about 75 species of tropical to subtropical siphonous green algae. To better understand the evolutionary history of the genus, a molecular phylogeny was inferred from chloroplast tufA sequences of 23 taxa. A sequence of Caulerpella ambigua was included as a potential outgroup. Results reveal that the latter taxon is, indeed, sister to all ingroup sequences. Caulerpa itself consists of a series of relatively ancient and species-poor lineages and a relatively modern and rapidly diversifying clade, containing most of the diversity. The molecular phylogeny conflicts with the intrageneric sectional classification based on morphological characters and an evolutionary scheme based on chloroplast ultrastructure. High bootstrap values support monophyly of C. mexicana, C. sertularioides, C. taxifolia, C. webbiana and C. prolifera whereas most other Caulerpa species show para- or polyphyly. Towards a phylogeny of Conostylis – a species-rich genus of Haemodoraceae (Western Australia) Michael F. Fay1, Stephen D. Hopper2, Vincent Savolainen1 and Mark W. Chase1 1Royal Botanic Gardens, Kew, Richmond,
Surrey, TW9 3DS, UK Talk — Subfamily Conostylidoideae of Haemodoraceae are endemic to the Mediterranean region of Western Australia, and Conostylis (with 46 species out of 77 species in the subfamily) is the largest genus in the family. To address a range of questions relating to mechanisms and timing of speciation, pollination syndromes, biogeographical patterns, edaphic requirements etc., we are working towards a phylogeny of the genus using DNA sequence data. We now have data sets for plastid matK and nuclear ribosomal ITS. Apart from the positions of a small number of taxa thought to be of hybrid origin, the topologies of the trees from separate analyses are highly congruent, and combining the data sets results in increased resolution and bootstrap support. Conostylis is strongly supported as monophyletic, and the monotypic genus Blancoa is strongly supported as sister group to Conostylis. Within Conostylis, the current classification into six subgenera is not supported. We recover two major clades, one predominantly composed of subgenus Pendula section Catospora and the other composed of two subclades, one composed of subgenus Pendula section Appendiculata and the other predominantly of subgenus Conostylis. The smaller subgenera Androstemma, Greenia, Brachycaulon and Bicolorata are all found in the Catospora clade, with several of the species occurring on the first branches of that clade. The three species of subgenus Pendula section Divaricata fall in three different positions, two in the section Cataspora clade and one in the subgenus Conostylis subclade. Although we still need to collect further data to produce a resolved tree, our existing data allow us to redefine subgeneric groupings and to reassess the characters that have been used to define the smaller subgenera and sections. Judith Fehrer1, Anna Krahulcová1, Franti_ek Krahulec1 and Siegfried Bräutigam2 1Institute of Botany, Czech Academy of
Sciences, Zámek 1, 25243 Pr_honice, Czech Republic Talk — Pilosella hawkweeds
(Asteraceae, Lactuceae) are known for their difficult taxonomic structure which is caused
by their mode of reproduction (facultative apomixis of the aposporous type) in combination
with frequent hybridisations. In an area where many of these species occur together, i.e.,
the three-border land of Germany, Poland and Czechia, the genetic structure of several
species and their presumed relationships was analysed by PCR-RFLPs and sequencing of cpDNA
intergenic spacers and by Southern hybridisations with mini- and microsatellite probes.
Additional information was obtained from morphological and cytological analyses (including
ploidy level determination), experimental hybridisations and reproduction studies. T.J. Givnish and R.A. Montgomery Dept. of Botany and the Gaylord Nelson Institute for Environmental Studies, 315 Birge Hall, 430 Lincoln Drive, University of Wisconsin, Madison, WI 53706, USA Invited talk - The Hawaiian lobeliads are considered one of the most spectacular cases of adaptive radiation in plants. From a single colonist, they have invaded habitats ranging from open alpine bogs to densely shaded rain-forest interiors, and evolved a striking diversity in leaf morphology. Yet very little is known about their ecology or - indeed - whether they have undergone an adaptive radiation in photosynthetic traits related to life in sun vs. shade. To address this question, we conducted a series of field and common-garden experiments on 11 species representing each Hawaiian sublineage. In field populations, average light levels for each species vary from 3.0 to 24.2 mol day-1, while Amax varies from 3.1 to 13.5 g CO2 g-1 s-1. Across species, variation in SLA, leaf longevity, carboxylation efficiency, and the compensation point, saturation point, and convexity of the static photosynthetic light response correlate significantly with light levels in the expected directions. To analyze the extent to which these differences are genetic (rather than merely being induced by the different light regimes inhabited by each species), we studied the photosynthetic responses and growth of plants at 6.5, 14, 33, and 80% full sunlight. Within a given light regime and across species, maximum photosynthetic rate and several other parameters varied as expected with native irradiance, with genetic differences among species for Amax apparently accounting for roughly 50% of the variance observed in the field. Species differed in their plastic responses to light regime, with one species outperforming all others at 6.5% sunlight; another species best at 14 and 30% sunlight; and a third species best at 80% sunlight. The sequence of these species corresponds to the range of irradiances they occupy in the field, as expected. This study is the first to provide evidence of adaptive divergence in photosynthetic light responses, reaction norms, and associated leaf traits among members of an adaptive radiation that have invaded different light regimes. Molecular dating of Coelogyninae (Orchidaceae) Barbara Gravendeel and Ed F. de Vogel Nationaal Herbarium Nederland, Universiteit Leiden branch, P.O. Box 9514, 2300 RA Leiden, The Netherlands Invited talk — Coelogyninae (c. 550 species) is a Southeast Asian subtribe of subfamily Epidendroideae in the Orchidaceae. According to recent molecular phylogenetic studies the tribe is monophyletic. Its sixteen genera are all sympodial, have pseudobulbs of one internode, terminal inflorescences and a winged column. Speciose genera of the Coelogyninae such as Coelogyne and Dendrochilum are often the most important elements in epiphytic vegetations in terms of biomass and species numbers. This makes the Coelogyninae an appropriate model for testing plant biogeographical patterns in Southeast Asia. Collisions between several ocean and land plates have created an intricate geological history for Southeast Asia and the West Pacific islands. Based on sequences of the plastid trnL-trnF intron and matK gene and nrITS1-5.8S-ITS2 region, we use a geology-calibrated molecular clock to address questions of geographic origin and age of several monophyletic clades in Coelogyninae. Data were obtained from 85 species in 14 genera covering the complete geographical range of the subtribe. Parsimony analysis of the combined data indicate that the deepest split is between Pleione, a small Himalayan genus, and all other Coelogyninae. Age estimates based on maximum-likelihood analysis are presented for this divergence. In addition, the dispersal of Coelogyne to the Pacific and the diversification of Geesinkorchis in Borneo and Sumatra are discussed. Josef Greimler & Chang-Gee Jang Department of Higher Plants Systematics and Evolution, Institute of Botany, Unviversity of Vienna, Rennweg 14, A-1030 Vienna, Austria Talk — In the genus Gentianella there
is evidence for reticulate relationships on different stages in their evolution.
Allopolyploid origin of tetraploid G. austriaca showing fixed heterozygosity can be
assumed from isozyme data. Wether this is also true for other taxa of Gentianella sect.
Gentianella (17 species plus some uncertain taxa in Europe: all tetraploids) still
remains to be investigated. In the current research we focuse on a probably much younger
level of reticulate relationsships. The gradual change in G. germanica when coming
closer to G. austriaca has long been recognized and has been treated taxonomically
in different ways. We reevaluate morphological evidence for this phenomenon in a large
Eastern Alps transect sample and investigate gene flow between the two taxa by using AFLP
fingerprint data. Conflicts in Combining Morphological and Molecular data Sets in the Thomsonieae (Araceae) G.B.J. Grob, W.L.A. Hetterscheid, P. Hovenkamp, R.W.J.M. van der Ham, M.C. Roos & P. Baas Nationaal Herbarium Nederland, Universiteit Leiden branch, P.O. Box 9514, 2300 RA Leiden, The Netherlands Talk — Tribe Thomsonieae (Araceae) consists of two genera of tuberous herbs: 1. Amorphophallus, a large and diverse genus of approximately 170 species, with a wide palaeotropical distribution, and 2. Pseudodracontium, a small genus, consisting of seven species only, all occurring in Indochina. At present we have a morphological data set of 165 species, and a four gene molecular data set for 54 species. In this study, results from phylogenetic analyses of these data sets are presented, and the differences discussed. Due to the disparity in numbers of the molecular and the morphological dataset, combining these datasets is problematical. We will discuss some of the problems encountered, and propose some new methods of combining the phylogenetic information contained in each data set. The results of these methods will be compared with those from traditional methods of combination.Finally, the implications of these results for Thomsonieae phylogenetics and future research will be discussed. Phylogeography of the submeditteranean bryophyte Pleurochaete squarrosa (Pottiaceae) in Europe Michael Grundmann & Johannes C. Vogel The Natural History Museum, Department of Botany, Cryptogamic Plant Research Division, Cromwell Road, London SW7 5BD, UK Poster — Phylogeographic methods have
provided the opportunity to elucidate the effects of large-scale historical events (such
as Pleistocene climate change) on the distribution and subdivision of biota and put in
context the role of reproductive biology in the genetic structuring of species. A broad
spectrum of organisms have provided grist to the phylogeographic mill including animal and
vascular plant taxa, but as yet there are few published studies of bryophyte
phylogeography. Amorphophallus (Araceae): the pollen point of view R.W.J.M. van der Ham, G.B.J. Grob & W.L.A. Hetterscheid Nationaal Herbarium Nederland, Universiteit Leiden branch, P.O. Box 9514, 2300 RA Leiden, The Netherlands Talk - Two main Araceae pollen types exist: 1. aperturate and 2. inaperturate. The aperturate type is plesiomorphic in the family. Amorphophallus pollen belongs to the inaperturate type. Its exine ultrastructure (presence, size, shape and distribution of dark granules) and ornamentation are much diverse. Ten main ornamentation types are present: psilate, striate, striate with psilate caps, fossulate, areolate, verrucate, echinate, reticulate, scabrate and striate/scabrate. Two of the three echinate subtypes are much alike the echinate pollen of the four closests outgroups used in the molecular work on the genus (Grob et al.: 48 spp., 4 genes): Arisaema, Filarum, Hapaline and Typhonium. However, echinate Amorphohallus pollen is not basal in the molecular tree, which suggests that the outgroups are only distantly related to the ingroup. No pollen traits indicating the monophyly of Amorphophallus or any of the main clades in the molecular tree were found. The main clades are dominated either by psilate or striate pollen, which occur basally as well as distally. The less common types are found more distally and mostly in single species. This suggests that either psilate or striate ornamentation is plesiomorphic. Outgroup comparison does not allow a choice, but thin psilate exines occur more or less basally in three of the four main clades. The generally thicker striate type is ultrastructurally heterogeneous, and seems to have evolved several times. Within both striate main clades, reversals to the psilate type occur, which are mostly characterised by greater exine thickness, compared with the basal psilate type. Within the African clade, thick psilate exines seem to have evolved directly from thin ones. Considering this, psilate pollen might be plesiomorphic in Amorphophallus. The rather common fossulate type is heterogeneous, and shows transitions to the psilate as well as the striate type. Also ultrastructurally, it proved to be diverse, and its diffuse distribution in the molecular tree confirms that it is polyphyletic. Striate pollen with psilate caps, which is nested in a striate clade (continental SE Asia), is a synapomorphy of Pseudodracontium (Indochina). In view of its typical exine ultrastructure, the psilate caps might have evolved in an albispathus/longituberosus-like ancestor. Reticulate (A. ochroleucus, Vietnam), scabrate (A. galbra, Queensland) and striate/scabrate ornamentation (A. smithsonianus, India) are considered as autapomorphies derived from psilate or striate forms. The other types, areolate, echinate and verrucate, occur in single species in the molecular tree, but have also representatives among the species not included in the analysis. Areolate pollen (6 spp., continental SE Asia) shows two alliances, one in a psilate main clade and another in a striate main clade. Echinate pollen (5 spp., Africa and Madagascar) is heterogeneous, showing three subtypes, one of which can be easily derived from a psilate type. Verrucate pollen (Africa: 5 spp. and India: 1 sp.) is clearly diverse. Derivation from psilate forms seems most likely. Several species appeared to be distinctly polymorphic: A. abyssinicus (verrucate, fossulate to coarsely striate), A. beccarii (psilate, striate-areolate) and A. baumannii (fossulate, coarsely striate, psilate, with or without distinct dark granules). These observations indicate that exine features are not always rigidly fixed, which might provide possibilities for rapid selection and evolution. Species-level Phylogenetics in African Restionaceae Christopher R. Hardy, Philip M. Moline and H. Peter Linder Institute of Systematic Botany, University of Zurich, CH-8008 Zurich, Switzerland Poster — The Cape Floristic Region (CFR) is characterized by unusually high levels of endemicity and species richness. Although there are some data available on the geomorphological and climatic history of the CFR, details of phylogenetic patterns within the plant groups that have radiated within the region are mostly lacking. As such, hypotheses regarding the origin and persistence of the species richness in the CFR remain speculative at best. As part of a larger, collaborative effort to test these hypotheses, we are investigating phylogenetic relationships within the African Restionaceae, a species-rich clade constituting a characteristic and often dominant element of the vegetation in the CFR. With over 350 species, the challenge lies in the discovery of variation useful for resolving relationships at all levels in the clade, in addition to acquiring robust estimates of the ages of cladogenic events based on underlying rates of molecular evolution. As such, we are employing variation at multiple loci from the plastid and nuclear genomes, in addition to morphological and anatomical variation. Our preliminary results indicate the value of a total evidence approach: morphological information is particularly useful in providing resolution among species, while the deeper nodes of the tree are more strongly supported by DNA sequence variation. These phylogenetic inferences, in turn, should facilitate the identification of factors governing the relative rates of speciation and extinction in this species-rich clade. Molecular markers and cytogenetical studies in Allium Sjaak van Heusden1, Ludmila Khrustaleva1,2 and Chris Kik1 1Plant Research International, P.O.
Box 16, 6700 AA Wageningen, the Netherlands Invited talk — Some aspects of advanced
breeding methods in Allium will be discussed. The two main topics will be: marker
assisted breeding and molecular cytogenetics. Marker-assisted breeding (MAB) is considered
as an important tool in modern plant breeding and therefore we have constructed a high
density AFLPTM map based on an interspecific cross between A. cepa
(onion) and A. roylei (van Heusden et al. 2000). On this map the position of the
gene which confers resistance to downy mildew (Peronospora destructor) is known. A
diagnostic marker for this gene is developed by using a sequence of a linked RAPD-marker.
We have also assigned the eight onion linkage groups to their physical chromosomes using
monosomic addition lines (van Heusden and Shigyo et al. 2000). More and more genomic
initiatives generate huge number of sequences of which many have a prediction function,
these kind of markers are preferred compared to anonymous markers like AFLP and RAPD. The
number of such expressed sequences located on the onion map is over 30 now and still
growing. Markers with known sequences make comparisons between different crosses more
feasible, examples will be given about correspondence between the three now existing onion
genetic linkage maps. Furthermore a start has been made to make an inventory of the level
of Single Nucleotide Polymorphisms (SNPs) in different onion cultivars. Khrustaleva, L.I. & C. Kik. 1998a.
Cytogenetical studies in the bridge cross Allium cepa x (A. fistulosum x A.
roylei). Theor. Appl. Genetics 96: 8–14. Polyploid formation and establishment in sympatry with ancestral diploid taxa Harriet V. Hunt1,2, Michael E. N Majerus1, Stephen J. Russell2, Fred J. Rumsey2 and Johannes C. Vogel2 1Department of Genetics, Downing
Street, Cambridge CB2 3EH, UK Poster — Asplenium majoricum Litard.
(Aspleniaceae) is an allotetraploid fern derived from Asplenium x protomajoricum, the
F1 hybrid between the diploids Asplenium fontanum and Asplenium
petrarchae subsp. bivalens. Asplenium majoricum is a rare Spanish endemic,
known from only a few sites on the island of Majorca and in the south of Valencia province
on the mainland. Timing the evolutionary divergence of crown group Gnetales: integration of molecular and fossil data Stefanie M. Ickert-Bond & Martin F. Wojciechowski Arizona State University, Department of Plant Biology, Box 871601, Tempe, Arizona 85287-1601, USA Poster — Efforts to date (and resolve) the evolutionary divergences of major land plant lineages using molecular sequence data have produced widely different age estimates. This has been attributed in part to dramatic differences in rates of molecular evolution among individual genes and lineages. Certain lineages, especially some ferns and Gnetales, show much higher than average rates of evolution in all data sets examined so far as well as in different codon partitions in protein coding genes. The Gnetales represent one of five extant groups of seed plants and recent studies have yielded strongly supported, but conflicting, hypotheses as to their phylogenetic relationships: in one, Gnetales are inferred to be the sister group to the remaining seed plants, in the other, Gnetales are nested close to conifers within a monophyletic gymnosperms. We have conducted phylogenetic analyses (maximum parsimony and maximum likelihood) on sequence data from two chloroplast genes, one a highly conservative photosystem gene, psaA, and a fast evolving plastid coding gene, rps4, across all major land plant lineages (2 lycophytes, 3 ferns, 5 angiosperms, all three genera of Gnetales, and nineteen other gymnsperms). Results of our analyses (based on all codon positions) were mostly congruent with parsimony and maximum likelihood results based on the same genes for different taxonomic samples as well as results based on other chloroplast genes. Using trees derived from both parsimony and likelihood analyses, and recently developed methods that allow for incorporation of rate heterogeneity and age constraints based on evidence from the fossil record, we estimate the age of crown group Gnetales. Preliminary estimates using models that are more clock-like give a date of 139 million years ago (mya) for the crown group Gnetales based on rps4, and an age of 179 mya for the psaA data. In contrast those models that incorporate rate heterogeneity indicate an age of 119 mya (rps4), while estimates on psaA data indicate that ages of the Gnetalian clade are again younger, 174 mya, than the fossil record from the Early Cretaceous (113 mya) indicates. Discrepancies of previous age estimates based on molecular sequence data (e.g., rbcL, 18S rDNA) are compared with results of this study and possible sources of error are discussed. Molecular biogeography and evolution of Nertera (Rubiaceae): from New Zealand to Tristan da Cunha Gerhard Jakubowsky, Michael Kiehn & Tod F. Stuessy Institute of Botany, Department of Systematics and Evolution of Higher Plants, Rennweg 14, A-1030 Vienna, Austria Talk — Nertera is a small genus of 13 species. The only widespread species, N. depressa, has an extremely disjunct distribution area and occurs in New Zealand, Australia, Indonesia, the Philippines, Taiwan, Hawaii, Meso- and South America, and Tristan da Cunha. All other species are endemic to relatively small areas; e.g., six to New Zealand, and two to the Tristan da Cunha archipelago. Material from populations of most species and of several populations of N. depressa from all over its distribution area were collected. ITS and trnL-F sequence data was used to build a phylogeny. The method of amplified fragment length polymorphism (AFLP) was also used as addition to the DNA data and for population studies on Tristan da Cunha. The phylogeny based on sequence data suggests that the genus evolved in New Zealand and spread into the Atlantic area and to South America. N. depressa, considered to be morphologically homogenous throughout it's distribution range, turned out to be genetically diverse; results indicate that populations from Meso- and northern South America (Costa Rica, Venezuela) and populations of southern South America (Chile) derived from two independent long distance dispersal events. AFLP data support the major clades of the phylogeny and show that the Tristan da Cunha populations are recent arrivals from southern South America; resolution of the N. depressa populations of Tristan da Cunha and the two endemic species (N. assurgens and N. holmboei) is weak and could indicate the recent development of the endemics. Evolutionary Relationships in Gentianella section Gentianella Chang-Gee Jang1, Barbara Hermanowski2 & Josef Greimler1 1Department of Higher Plants
Systematics and Evolution, Institute of Botany, Unviversity of Vienna, Rennweg 14, A-1030
Vienna, Austria Poster — The European Gentianella section
Gentianella is commonly divided into 3 groups around the most common taxa: (1) Gentianella
campestris, (2) Gentianella amarella, (3) Gentianella germanica. Whereas
(1) and (2) are essentially distributed in northern Europe, the (3) Gentianella
germanica-group exhibits its highest diversity in the central and southeast European
mountains, especially the Alps, where many alpine endemics can be found. We here
reevaluate morphological characters and investigate genetical data for better
understanding between and within groups relationships. The temporal course of Quaternary plant speciation Joachim W. Kadereit & Hans-Peter Comes Institut für Spezielle Botanik und Botanischer Garten, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany Invited talk — Molecular phylogenies based on ITS sequences, a molecular clock approach, and lineages through time plots of Gentiana sect. Ciminalis (Gentianaceae), Primula sect. Auricula (Primulaceae) and Soldanella (Primulaceae) have been used to investigate the temporal course of speciation in European high mountain plant taxa of similar overall geographical distribution. The following results were obtained: 1) The three taxa investigated are of different
absolute age. Speciation is not evenly distributed across time.
Instead, speciation took place only in the early part of the history of the three taxa.
Their more recent history shows only intraspecific differentiation. This is attributed to
the continuous filling of ecological and/or geographical space or the decrease of range
sizes reducing the likelihood of speciation. This results in a characteristic deviation of
observed in comparison to expected diversification within the three taxa (assuming
constant speciation and extinction rates): Whereas in the early part of their history
(approximately the first half) observed diversification does not deviate from expected
diversification, observed diversification in their more recent (approximately the second
half) history falls short of expected diversification. Paul J.A. Keßler1, Ramadhanil Pitopang2, Merijn Bos1 & S. Robbert Gradstein3 1Nationaal Herbarium Nederland,
Universiteit Leiden branch, P.O. Box 9514, 2300 RA Leiden, The Netherlands Poster - Lore Lindu National Park, Central
Sulawesi, Indonesia is one of the hotspots of bio-diversity East of the Wallace line.
Within the framework of STORMA (Stability of Rainforest Margins) we analyse structural
tree diversity in four different land use systems, i.e. Natural Forest, Forest Garden,
Fallow, and Cacao Plantations Naomi Kingston1 & Steve Waldren2 1Department of Botany, Trinity
College, Dublin 2, Ireland Poster - The ‘Lusitanian’ (or Hiberno-Cantabrian) element of the Irish flora consists of a suite of species found mainly in the west of Ireland and the western Iberian peninsula, which include four species from the Ericaceae; Arbutus unedo, Daboecia cantabrica, Erica erigena, Erica mackaiana. Questions have been raised about whether this group repeatedly recolonised Ireland from southern European refugia following glacial episodes, or whether they survived full glacial cycles in more proximal refugia. This group of species is therefore of considerable European conservation importance, and its study will also be relevant to past and present climate change scenarios. Both AFLP and chloroplast microsatellite markers will be used to determine the relationships within and between the Irish populations, and their relationships to the Spanish populations. This will facilitate the estimation of a timeframe for divergence of Irish and Continental populations, and thus establish if Irish populations are ancient Pleistocene or recent Holocene colonisers. Phylogeny of the genus Saussurea (Asteraceae) in East Asia Yoko Kita1, Fujikawa Kazumi2 & Motomi Ito3 1Department of Biological Sciences,
University of Tokyo, 7-3-1 Hongo, Tokyo 113-0033, Japan Poster — The genus Saussurea includes 300–400 species (Lipschitz, 1979; Bremer, 1994). To examine the geographical diversity of Japanese Saussurea, we analyzed species of Saussurea subgenus Saussurea from Taiwan, Korea, China, Nepal, and Russia. There are 23 species in Japan. Saussurea nipponica that is found throughout Japan has five identified subspecies (Im, 1991). Sequences of the nuclear ribosomal ITS region and the chloroplast matK gene were used for phylogenetic analysis. In the ITS tree, all the Saussurea except two species, S. deltoidea and S. auriculata, formed a strongly supported monophyletic group. All the species examined in the subgenus Theodorea formed a monophyletic group. This clade was the sister group to a clade containing subgenus Saussurea section Laguranthera. S. glacialis and S. gnaphalodes from subgenus Eriocoryne were the sister of S. involucrata from subgenus Amphilaena and the remaining 29 taxa examined in the subgenus Saussurea. 19 taxa of East Asian Saussurea formed a clade containing three groups (Taiwanese alpine clade, Honshu Island clade, and Shikoku and Kyushu Islands clade), one Korean species, and three from NE China. The subspecies of S. nipponica are very diverse morphologically. The ITS tree revealed that this species is a polyphyletic group; subspecies from Honshu Island were more closely related to Taiwan alpine species than to subspecies from Shikoku and Kyushu Islands. The matK sequence provided little resolution for the relationships of the Saussurea species and the topologies of the matK and ITS trees disagree. A cloning and sequencing approach for the ITS region was adopted for eight taxa, in the hope that this method would provide novel insights into the disagreement between the ITS and matK trees. Martin Kolník1 & Karol Marhold1,2 1Institute of Botany, Slovak Academy
of Sciences, Dúbravská cesta 14, SK-842 23 Bratislava, Slovak Republic Poster — The aim of our recently started
project is to perform taxonomic revision of the species traditionally treated within the
genus Cardaminopsis (C.A. Mey.) Hayek (Brassicaceae) in the Carpathians, and
to evaluate their relationships to the populations from the Eastern Alps. Depending on the
taxonomic concept, the genus Cardaminopsis comprises 12 species (Markgraf, 1960),
or 8 species and several subspecies (Jalas & Suominen, 1994). However, neither
morphological nor molecular data have provided support for the recognition of this genus,
and recently, the taxa of the genus Cardaminopsis were included in the genus Arabidopsis
Heynh. (O’Kane & Al-Shehbaz, 1997; Koch, Bishop & Mitchell-Olds, 1999). Towards a monograph of the genus Cardamine (Brassicaceae) Jaromír Kucera1, Judita Lihová1, Karol Marhold1,2 and Marián Perny1 1Institute of Botany, Slovak Academy
of Sciences, Dúbravská cesta 14, SK-842 23 Bratislava, Slovak Republic Poster — The genus Cardamine includes
worldwide more than 200 species and is distributed in all continents except for
Antarctica. A large karyological and morphological variability is typical for numerous
species groups of this genus. Some of them have already been thoroughly studied, other
still wait for the taxonomical revision. Low levels of sequence variation accompany speciation in Kunzea (Myrtaceae) Peter de Lange1,2, Brian Murray1, Tristan Armstrong3, Helmut Toelken4 1 School of Biological Sciences, The
University of Auckland, Private Bag 92019, Auckland, New Zealand Talk - There has been an increased reliance on
the use of phylogenetic techniques using DNA markers to aid with the resolution of
problematic New Zealand genera. However, when compared with other more traditional
taxonomic techniques, there is often insufficient variation to resolve species complexes. Polyploid evolution in Cardamine amara (Brassicaceae) Judita Lihová1 & Karol Marhold1,2 1Institute of Botany, Slovak Academy
of Sciences, Dúbravská cesta 14, SK-842 23 Bratislava, Slovak Republic Poster — In our recent taxonomic treatment
of Cardamine amara, several diploid and two tetraploid subspecies have been
recognized in Europe. The tetraploids are represented by C. amara subsp. austriaca
occurring in the Eastern Alps and adjacent areas, and by C. amara subsp. olotensis
from Catalonia, NE Spain. In the present study we used combined morphometric and molecular
(RAPD, AFLP, isozymes) approach to investigate these two tetraploid taxa in more detail,
and to explore polyploid evolution in C. amara. Speciation in the Cape flora: a macro-evolutionary perspective Peter Linder & Chris Hardy Institute for Systematic Botany, University of Zurich, Zollikerstr. 107, CH-8008 Zurich, Switzerland Invited talk — The Cape Floristic Region, although only 90 000 km2 in area, includes 9 000 species, of which almost 70% are endemic to the region. This makes it one of the more species-rich areas in the world. Furthermore, most of these species are found in large to small, subendemic to endemic, genera, indicating that much of the speciation must have happened within the Cape Floristic Region. This therefore constitutes a very suitable area in which to study the historical and environmental factors which may be involved in this remarkable speciation, and in the continued co-existence of this large number of species. Such an approach could be described as being macro-evolutionary and macro-ecological. Previous reviews and investigates implicated several factors: geographical isolation resulting from the dissected landscape or recurrent fires; strong selection resulting from the steep rainfall and temperature gradients; adaptation to different soils resulting from different bedrock types; adaptation to different pollinators in clades with a high level of pollinator specificity; and different responses to the different strategies for surviving recurrent wild fires. Here we investigate the possible relative contribution of these factors in several clades (e.g. Disa (Orchidaceae), Thamnochortus (Restionaceae), Liparia (Fabaceae)). However, it is evident that these factors are not mutually exclusive, and that evaluating the relative significance of each is difficult, consequently we will explore various methods that can be used in the search for patterns among the factors that might be driving the speciation process. Studies on Brazilian grasses and sedges Hilda M. Longhi-Wagner1, Ana Cláudia Araujo2, Ana Zanin3, Thaís do Canto-Dorow4 & Tatiana Chies1 1Dept. of Botany, Universidade Federal
do Rio Grande do Sul, Av. Bento Gonçalves 9500/ 43433 – 91501-970, Porto Alegre, RS,
Brazil Poster — The family Poaceae includes c. 650 genera and 10,000 species, according Watson & Dallwitz (The grass genera of the world, 1992). According to Burman (Willdenowia 15, 1985) c. 200 genera and 1,400 species occur in Brazil. Luceńo & Alves (Candollea 52/1, 1997) cited 100–120 genera and c. 5,000 species of Cyperaceae of which c. 44 genera and 500–600 species for Brazil. Most of the taxonomical and floristic studies on these two families in Brazil have been based on a classical morphological approach. In the last decade other approaches started to be used in the revisions of several genera in Brazil as well as monographic worldwide studies at generic and infrageneric levels. Besides the macromorphological approach, other evidences are being used such as leaf anatomy, micromorphology of fruit surface in SEM and DNA sequencing. Leaf anatomy and micromorphology of the fruit surface are providing more useful taxonomic characters in Poaceae than in Cyperaceae at infraspecific level and interspecific relationships. The nine species of Cyperus L. subg. Anosporum (Nees) Clarke from Rio Grande do Sul, Brazil, studied by Araujo & Longhi-Wagner (Iheringia 48, 1997) could be differentiated by leaf anatomy and fruit surface ornamentation. The proposal of a modification of the circumscription of Rhynchospora sect. Pluriflorae Kük. (Cyperaceae) was based in a cladistic analysis combining macromorphological and anatomical (leaf) data. DNA sequencing was used to define the circumscription of Rhynchospora consaguinea Kunth Complex (Araujo, PhD thesis, 2001). Although the leaf anatomy and the ornamentation of fruit surface in Brazilian species of Andropogon L. (Poaceae) were quite homogeneous, it was possible to use these characteristics to separate some macromorphologicaly very similar species (Zanin, PhD thesis, 2001). In the genus Digitaria Haller (Poaceae), leaf anatomy also gave support to define the circumscription of similar species (Canto-Dorow, PhD Thesis, 2001). The study of Panicum L. subg. Panicum (Poaceae) and the revision of Raddia A. Bertoloni (Poaceae) and related genera are being carried out using macromorphology, leaf anatomy, analysis of the upper lemma surface in SEM and DNA sequencing. A molecular approach (DNA sequencing and RAPD markers) is being used in the genus Paspalum L. (Poaceae) to analyse the circumscription of some groups and the genetic variability in these groups. The change in approach represents a substantial progress in these taxonomic studies. The improved results fully justify the efforts and investments in this area. On the other hand, floristic surveys of grasses and sedges in different areas of Brazil continue to be done, and the traditional methods are still extremely important for the much needed general floristic work in countries like Brazil. Cowpea germplasm for disease and pest resistance Abby Lubega, M. Biruma & Harunah Kasozi National Teachers College Mubende, Uganda Diseases and insect pests are the major production constraints to cowpea production in Uganda. Therefore it is often necessary to control pests and disease infestations on cowpea in order to avert economic losses. Use of resistant cowpea cultivars is the most appropriate control strategy for the resource-poor farmers. In Uganda, however, cowpea varieties resistant to insect pests and diseases are largely unknown. This study therefore was conducted to evaluate and screen both local and elite materials for disease and pest resistance. The experiments were carried out at Makerere University Agricultural Research Institute Kabanyolo (MUARIK) for two growing seasons (i.e., during the short rains of 2000 and long rains of 2001). A total of 200 and 177 entries were evaluated in 2000 and 2001, respectively. For each variety, 15 plants were planted in a single row using a seed rate of two plants per hill at a spacing of 20 cm between plants and 90 cm between rows. Two replicates were used for each variety and the experiment was laid out as a randomised complete block design. Disease and pest infestation were monitored and data taken. In addition, at harvest maturity yield data per variety row was taken. Preliminary results indicate that a number of varieties exhibit multiple and specific resistance. These lines are recommended for advanced testing trials. Taxonomy and evolution of polyploid complexes in Cardamine (Brassicaceae) in Europe Karol Marhold1,2, Judita Lihová1 & Marián Perny1 1Institute of Botany, Slovak Academy
of Sciences, Dúbravská cesta 14, SK-842 23 Bratislava, Slovak Republic Talk — The genus Cardamine in its
European area includes several polyploid complexes. Among them, three traditionally
recognized groups of taxa, namely C. amara, C. pratensis and C.
raphanifolia, are most variable. They include examples of euploids, aneuploids as well
as dysploids, and the ploidy level extends up to the dodecaploid one. Such complicated
karyological variation is also partly reflected in morphological variation, and this
brings inevitable problems and open questions of its taxonomic classification and related
evolutionary interpretations. Recent karyological, morphological and molecular systematic
studies, using isozyme, DNA sequence, RAPD and AFLP data, brought some light into these
problems. Jörg Meister1, Norbert Kilian1, Mohamed Ali Hubaishan2 & Christoph Oberprieler1 1ZE Botanic Garden and Botanical
Museum Berlin-Dahlem, Königin-Luise-Str. 6-8, D-14191 Berlin, Germany Poster — Since the Arabian Peninsula was
separated from the African continent not earlier than in the Oligocene, E Africa and the
Arabian Peninsula had a common tropical flora and vegetation. At the same time, migration
and exchange between the xerotropical floras of Asia and Africa were possible across the
Arabian Peninsula. Due to the aridisation of the entire region in the late Tertiary, the
palaeo-African flora and vegetation was then forced into the south of the Arabian
Peninsula, isolated from Africa, with increasing aridity finally fragmentised and
delimited to refuge areas. These fragmented refuge areas of the coastal mountains in the
Southern Arabian Peninsula with their endemic flora and unique vegetation are in the main
focus of our investigations which are carried out as partial projects (BIOTA East Africa
E13-E16) in the BIOLOG Programme on Biodiversity and Global Change funded by German
Federal Ministry of Education and Research (www.biota-africa.de). Marlien van der Merwe1, A-M Oberholster2 & AE van Wyk1 1Department of Botany, University of
Pretoria, Pretoria, 0002 South Africa Poster — Eugenia is a large genus in Myrtaceae (Myrtoideae) with more than 900 species occurring in the Americas, the Mascarene Islands, Africa, Asia and Australia, the bulk of the species being centred in South America. In southern Africa 14 species are recognised. Members of Eugenia are characterised by very little macro-morphological variation and the circumscription of infrageneric taxa has long been problematic. Among southern African members two groups (X and Y) were proposed based on anatomical and micro-morphological characters. The relationship of southern African Eugenia with its counterparts elsewhere in the world is not clear. In this study chloroplast DNA regions were used to establish if molecular data supports the sub-grouping of the southern African members. Furthermore the relationship of southern African taxa with those from Mauritius (including Monimiastrum) was investigated. A few species representative of the distribution range of the genus elsewhere in the world were included in the analysis. Four chloroplast regions, trnL-F intron, rpl22 intron, psbA-trnK region and the rpl16 intron, were sequenced for a few of the species and alignments compared. Over all very little sequence variation was found. The rpl16 intron was the most informative and sequences of this region were obtained for all taxa. Among the southern African members of Eugenia two clear groups could be identified. These groups are congruent to what has been found with the anatomical and morphological data. The rpl16 intron sequence data thus supports the division of southern African Eugenia into groups X and Y. Eugenia and Monimiastrum from Mauritius seem to be most closely related to the larger of these groups (Y). Although the relationship is not clear, group X would appear to be more closely related to Eugenia from the New World. The rpl16 intron did not resolve any relationships among closely related species possibly due to slow sequence divergence. The region nevertheless holds considerable promise to assist in elucidating the infrageneric phylogeny/classification of the genus. Species barriers maintained by strong extrinsic selection at the second hybrid generation Richard Milne & Richard Abbott Division of Environmental and Evolutionary Biology, School of Biology, University of St Andrews, St Andrews, Fife, KY16 9 TH, Scotland, UK Talk — Isolating barriers between sympatric interfertile species are maintained by processes that occur within their hybrid zones. Although the effects of intrinsic selection on hybrid fitness are well known, less is understood about extrinsic fitness variation. At Tiryal Dag, NE Turkey Rhododendron x sochadzeae (R. ponticum x caucasicum) forms large populations in which neither segregation nor backcrossing occur, in habitats intermediate between those of its parents. Using single-copy species-specific RAPD and ISSR markers, it was determined that all R. x sochadzeae plants are F1s, and that there are many separate genets present. Through hand pollination experiments, it was determined that R. x sochadzeae plants can produce viable seed of F2s or backcrosses in either direction. Therefore, all non-F1 hybrid derivatives appear to be eliminated at Tiryal Dag due to post-germination selection.. However, adult backcrosses can and do recruit in large numbers in different habitat conditions at another site. From this, the selection that favours F1s over BCs at Tiryal Dag must be habitat-mediated. We have concluded that strong habitat-mediated selection is most likely maintaining species barriers at Tiryal Dag by eliminating hybrid generations subsequent to F1. Similar forces might occur in other hybrid zones, but be countered by additional effects that increase fitness in post-F1s, or restrict formation and/or fitness of F1s. Possible mechanisms that might underlie habitat-mediated superiority of F1s will be discussed. Identifying clades in Asian soursops – molecular phylogeny of Miliusa and Polyalthia (Annonaceae) Johan B. Mols, Paul J.A. Keßler & Barbara Gravendeel Nationaal Herbarium Nederland, Universiteit Leiden branch, P.O. Box 9514, 2300 RA Leiden, The Netherlands Talk — The Annonaceae are a pantropical
family of trees, shrubs and lianas consisting of c. 130 genera and 2300 species. Although
the family is clearly defined, generic and tribal delimitation of especially the Asian
Annonaceae is controversial due to many overlapping morphological characters. The main
goal of this study was to reconstruct a molecular phylogeny of the genus Miliusa,
which is traditionally assigned to the tribe Miliuseae together with five other genera,
and of the genus Polyalthia which is generally regarded to be a polyphyletic genus. Alexandra N. Müllner1, Rosabelle Samuel1, Mark W. Chase2 & Harald Greger3 1Institute of Botany and Botanical
Garden, Dept. of Higher Plant Systematics and Evolution, University of Vienna, Rennweg 14;
A-1030 Vienna, Austria Talk — Aglaia, the largest genus of the woody family Meliaceae (Sapindales) and comprising more than 100 species, occurs in the tropics of southeastern Asia, the Pacific islands and northern Australia. The diversity within the genus, constituting one of the most important sources of biologically active compounds within the family, has become severely threatened due to overexploitation and habitat loss. Boundaries between the two currently recognized sections (Aglaia and Amoora) and between most of the species have remained unclear until now. This study was carried out to infer phylogenetic relationships among Aglaia species using sequence data from the ITS region of the nuclear ribosomal DNA and the rps16 intron of plastid DNA. Species of all two sections of Aglaia plus closely related Meliaceae genera belonging to the same tribe within subfamily Melioideae, as well as members of other tribes within the family were included. Single ITS and combined phylogenetic analyses of ITS and rps16 support the recognition of three groups within Aglaia. One group comprises species previously assigned to section Amoora based on dehiscence of their fruits. Two other species, A. teysmanniana and A. lawii, with flower characters intermediate between the two sections, but assigned to section Amoora based on dehiscence of their fruits, form another group together with some other representatives of section Aglaia. The third, largest and most diverse group comprises species formerly assigned to section Aglaia based on their indehiscent fruits. Concerning boundaries between and within species, DNA data indicate it may prove necessary to divide some of the morphologically variable and complex species into two or more (sub)species (e.g. A. elliptica, A. tomentosa). Inheritance and genetic variation of enzymatic markers in Cerastium alpinum Anna-Britt Nyberg Berglund1 & Anna Westerbergh2 1Department of Natural and
Environmental Sciences, Mid Sweden University, S-851 70 Sundsvall, Sweden Talk — The polyploid plant Cerastium alpinum (Caryophyllaceae) is common in the Scandinavian mountain range where it grows on alpine heaths and serpentine soils rich in heavy metals. It is also found in the subalpine and boreal region where it grows on serpentine, dolomite and steep slopes. Analysis of enzymatic variation among populations on various soil types has shown two major genetic groups, which suggests that C. alpinum colonized Scandinavia both from the east and the west after the last glaciation. Large genetic differences among populations within each genetic lineage were also found. This suggests that the populations are effectively isolated from each other. Restricted gene flow could be explained by a high degree of selfing or inbreeding as wel as limited pollinator flights between populations. To distinguish between the alternatives we will analyze the genetic structure within populations in the eastern and western groups. But before that we need to elucidate the mode of inheritance of enzyme markers that will be used. When a suitable model for the gamete formation is found, it is possible to calculate expected frequencies of different zygotic phenotypes under random union of gametes and to compare this with the observed number of different enzyme phenotypes. At the Pgi-2 and Tpi-3 loci no segregation was observed for crosses between heterozygous individuals. Such fixed heterozygosity is a common feature in allopolyploids. However, two different fixed patterns in Pgi-2 was found, which suggest that at least two different polyploidization events have occurred during the evolution of this species. The progeny from selfed plants heterozygous for two alleles at the Mr-1 locus segregated in a 2:2:1 ratio. The large proportion of homozygotes suggests a disomic rather than polysomic inheritance. The surplus of one of the homozygotes may indicate some detrimental effects of selfing because a 1:2:1 ratio was found in crosses between individuals. C. alpinum seems to be diploidized at the Mr-1 locus. Assuming a diploid model for inheritance in this marker, deficiencies of heterozygotes was found in about half of the populations in both the eastern and the western group. This may indicate that a high degree of selfing can restrict the gene flow among populations of C. alpinum. Separating population structure from population history in the fucoid seaweed Ascophyllum nodosum Jeanine L. Olsen Department of Marine Biology, Centre for Ecological and Evolutionary Studies, University of Groningen, 9750 AA Haren, The Netherlands Invited talk — Ascophyllum nodosum is a dominant seaweed along many rocky intertidal shores throughout the North Atlantic. Next to the kelps, fucalean taxa such as Ascophyllum are the largest macrophytes and provide important habitat for invertebrates. Understanding the underlying genetic structure of natural populations over a range of spatial scales – meters to thousands of kilometers – can reveal how the causes of structure may change with scales. Here I analyze six polymorphic microsatellite loci in >1000 individuals. Strong genetic structure at small spatial scale (<10 m and up to 1 km) was found and is consistent with demographic models based on long-lived individuals, low recruitment and many sib matings. At intermediate scales (1–100 km), isolation by distance was found to follow a stepping stone model. At large spatial scales only weak population differentiation was found and tree-topology is characterized by shallow divergences. Given that the entire North Atlantic was recolonized only within the past 10,000 years, such a pattern is consistent with a rapid sweep from southern refugia as A. nodosum does not occur in the Pacific. The Brittany peninsula is characterized by high allelic diversity and appears to be a biodiversity hotspot for many cold-temperate taxa. Seed protein analysis as a tool for taxonomy of Alcea (Malvaceae) in Iran Maneezhe Pakravan Biology department, Alzahra University, Vanak sq.,Tehran, Iran Poster — The genus Alcea L. is represented by 34 species in Iran. Seed protein extracted from the 27 species and 4 variety and compared by SDS-PAGE electrophoresis method. For analysing the species on the baseis of bands obtained from the electrophoresis of their protein extract the coefficient of simple matching and average linkage clustering techniques (UPGMA) were utilized. The results supporting the present delimitation of the species. The data showed that species can be separated by their protein patterns and they also support the relationships of some morphologically close species. Pieter Pelser, Barbara Gravendeel & Ruud van der Meijden Nationaal Herbarium Nederland, Leiden University branch, P.O. Box 9514, 2300 RA Leiden, The Netherlands Talk — The species composition and molecular phylogeny of Senecio sect. Jacobaea (Asteraceae; Senecioneae) were studied to identify the closest relatives of Senecio jacobaea. This information is of great importance to studies using S. jacobaea as a model system to investigate the evolution of chemical defense strategies. Maximum parsimony and Bayesian inference analyses of DNA sequence data of the plastid genome (the trnT-L igs, the trnL intron, two parts of the trnK intron, flanking both sides of the matK gene, and the psbA-trnH igs) and nuclear genome (ITS1, 5.8S, and ITS2) identified 24 species as members of section Jacobaea. Phylogenetic analyses also indicated that DNA sequence markers can be used to study the phylogeny of sect. Jacobaea, although relationships between closely related species were sometimes poorly resolved due to low levels of sequence variation between the accessions and incongruence between the plastid and nuclear data set. Hybridization might have been an important factor in the evolutionary history of sect. Jacobaea. Contrary to the DNA sequences, phenetic and maximum parsimony analyses of AFLP data resolved evolutionary relationships between closely related taxa in sect. Jacobaea, both at the inter- and intraspecific level. Taxonomy and evolution of Cardamine raphanifolia Marián Perny1 & Karol Marhold1,2 1Institute of Botany, Slovak Academy
of Sciences, Dúbravská cesta 14, SK-842 23 Bratislava, Slovak Republic Poster — Five infraspecific taxa have generally been treated under Cardamine raphanifolia Pourr. in Europe (C. raphanifolia subsp. raphanifolia, subsp. gallaecica, ‘proles’ calabrica, subsp. acris, subsp. barbareoides); two of them were by some authors left in species rank as originally published (C. acris, C. barbareoides). In addition, three taxa with mainly Caucasian and Near East distribution (C. tenera, C. uliginosa, C. seilditziana) were usually considered as closely related to European populations. Taxonomic and evolutionary relationships in a ‘Cardamine raphanifolia group’ thus defined have not been studied in detail until now, treatment of the taxa in floras is often confusing, and identity of many populations is not clear. We performed karyological, morphological and molecular studies of populations from European part of distribution area of this group. The aims were to produce a taxonomic revision of the group in Europe as well as to give insights into its evolution. Considerable karyological variability was observed in Iberian populations – subsp. gallaecica: 2n=32, 48; subsp. raphanifolia: 2n=48, 64 (x=8). C. raphanifolia ‘proles’ calabrica from S Italy is hexaploid with 2n=48; subsp. barbareoides from NW Greece is tetraploid with 2n=32, and remaining Balkan populations of subsp. acris are diploid: 2n=16. Multivariate morphometric analyses of thirty seven quantitative characters included exploratory data analysis, principal component analysis, cluster analyses and discriminant analyses. Analyses revealed (1) intermediate position of populations of subsp. gallaecica between subsp. raphanifolia and C. amara subsp. pyrenaea, with good separation of these taxa by several morphological characters but low morphological difference among different cytotypes within the first two taxa; (2) separation of hexaploid Calabrian populations from diploid Balkan populations as well as from Iberian populations, and (3) complicated variability of both quantitative and qualitative morphological characters among Balkan populations. Results of AFLP study of 160 accessions including Asian taxa related to C. raphanifolia and selected taxa from the C. amara and the C. pratensis groups confirmed clustering of populations within particular taxa which correspond to that from morphometric analyses, but on a higher level (1) placed tetraploid C. barbareoides accesions within C. amara s.l. cluster, (2) placed hexaploid Calabrian populations within C. acris s.l. cluster, (3) revealed genetic relatedness of Iberian populations of subsp. raphanifolia and subsp. gallaecica; and (4) gave support for monophyly of Caucasian acccesions. Taxonomic conclusions from the three sources of data: subspecies of C. raphanifolia should be treated on the level of species. Evolutionary implications: the patterns of morphological characters as well as molecular and karyological evidence indicate reticulate evolution by polyploidy and hybridization. Evolution of endemic vascular plants of Ullung Island, Korea M. Pfosser1, T. Stuessy1, B.-Y. Sun2 , H. Weiss1, Y.-P. Guo2, T. Fer2 & C.-G. Jang2 1Department of Higher Plant
Systematics and Evolution, Institute of Botany, University of Vienna, Rennweg 14, A-1030
Vienna, Austria Talk — Ullung Island is of volcanic origin and lies 150 km E of peninsular Korea in the Eastern Sea. It has a surface area of 72 sq. km. and a high central point of 985 m. On this isolated oceanic island occur 700 vascular plant species, of which 28 are endemic. All but six of these species are their only generic representatives. For the other three pairs of species (in Acer, Carex and Viola) they are not closely related to each other. The pattern of phylogeny in Ullung Island, therefore, appears to be by anagenesis, i.e. immigrants having arrived and diverged without further cladogenesis. The young age of the island (1.8 my) and its relatively uniform ecology may explain this lack of additional speciation, so characteristic of other oceanic islands. Comparison of continental progenitor and endemic island derivative, therefore, can provide insights on initial stages of island speciation, especially involving cytogenetic and genetic changes. We have analyzed progenitor and derivatives in Acer (Sapindaceae), Dystaenia (Apiaceae) and Hepatica (Ranunculaceae) using a combination of data from FISH, GISH, DNA sequences (ITS, trnL-F, chloroplast microsatellites, and AFLPs. Progenitors for endemic Acer okamotoanum and A. takesimense came from peninsular Korea (from A. mono and A. pseudosieboldianum, respectively) as did that for Hepatica maxima (from H. asiatica), but Dystaenia takesimense has originated from D. ibukiensis from Japan. Based on samples of peninsular populations, AFLP data suggest specific geographic regions for origin of most of the island endemics. Only in Acer okamotoanum populations do DNA data indicate multiple origins and/or multiple genetic exchange with progenitor populations. No cytogenetic changes can be detected in the origin of the endemic species of Acer or Hepatica, but loss of satellite and/or B-chromosomes and NOR regions has occurred during speciation of Dystaenia takesimana. Radiations in the Oncidioid orchids Martyn P. Powell1,4, Franco Pupulin3, Jorge Warner3, Lars Chittka2, Mark W. Chase1 & Vincent Savolainen1 1Jodrell Laboratory, Royal Botanic
Gardens, Kew, Richmond, Surrey, TW9 3DS, UK Talk — Oncidioid orchids (subtribe Oncidiinae) demonstrate an extraordinary radiation, comprising over 1700 species in tropical America. We evaluate the role mimicry has played in this radiation in the neotropical forests of Costa Rica. In order to allow for a more specific study of visual mimicry, we analysed colour distributions and floral reflectance of sympatric plants from twenty sites, where an oncidioid orchid was central to the site. As bees are the most common pollinators in these communities and almost certainly the pollinators of oncidiod orchids, we used a model of their colour vision to conduct the study and preliminary analyses of the data indicates that two basic types of orchid mimicry are in operation: (i) oncidioid orchids of the genera Oncidium and Erycina strongly reflect both yellow and ultra-violet light, a characteristic shared only with Byrsonima crassifolium (Malpighiaceae); and (ii) other oncidioid orchids tend to converge on the rest of the community without displaying any unique differences. Molecular evolution of non-coding chloroplast DNA Dietmar Quandt1, Michael Stech2, Kai Müller1, Sanna Huttunen3, Khidir W. Hilu4 & Thomas Borsch1 1Botanisches Institut und Botanischer
Garten, Rheinische Friedrich-Wilhelms-Universität Bonn, Meckenheimer Allee 170, D-53115
Bonn, Germany Talk — Non-coding regions are becoming
increasingly popular for inferring phylogenies at different taxonomic levels. In spite of
their wide application, comparatively little is known about variability, evolution, and
functional constraints of these regions. In the present study we investigate molecular
evolutionary patterns in a variety of non-coding chloroplast regions, such as the atpB–rbcL
intergenic spacer, the psbT-H gene cluster (coding for photosystem II proteins),
and the trnT-F region. These are among the most widely used non-coding chloroplast
regions in plant systematics. Various examples of molecular evolutionary patterns of these
non-coding regions are presented and their possible influence on phylogeny reconstruction
is discussed. Patterns of variation in Cynara: a preliminary molecular study Lavinia Robba1, Mark A. Carine2 & Francesco M. Raimondo1 1Department of Botany, Palermo
University, via Archirafi 28, I-90123 Palermo, Italy Poster — Cynara L. (Asteraceae,
Cardueae) is native to the Mediterranean basin. It includes the globe artichoke (Cynara
scolymus L.), a widely cultivated food plant, the cardoon (Cynara cardunculus L.),
also cultivated for its leaves, together with 7 other wild species. All wild species are
perennial and the genus is characterised by large spiny leaves and heads. In Flora
Europaea (1976) the genus was divided into 3 sections based on the presence or absence of
stem, the shape and structure of cauline leaves, involucre, middle and upper involucre
bracts and achenes. However, in a recent revision of the genus, Cynara tournefortii
Boiss. & Reuter, a species endemic to the Iberian peninsular and north Morocco very
distinctive because of its total lack of stems, was treated as a separate monotypic genus Arcyna.
Barbara Rudolph1, Milena I. Uzunova2 & Wolfgang Ecke3 1University of Hamburg, Institute of
General Botany and Botanical Garden, Module Systematics, Ohnhorststr. 18, 22609 Hamburg,
Germany Poster — The amphidiploid Brassica napus
genome (n = 19) appears to have arisen polyphyletically by several interspecific
hybridization events between the diploids Brassica campestris (n = 10) and Brassica
oleracea (n = 9). This seems to be a natural mechanism, occurring also in
other amphidiploid species of Brassica. RFLP analyses suggest that it is followed
by reshuffling of the amphidiploid genome, e.g., chromosome rearrangements, gene
conversions, loss of chromosome fragments and/or duplication of genome regions. Some of
these genome rearrangements were easily traceable by simple sequence repeat (SSR)
analyses. We constructed a set of 129 primer pairs flanking microsatellites, and 113 of
them showed reproducible amplification products in 38 Brassica napus lines. Whereas
microsatellite markers are usually regarded as ‘one locus markers’, our first
tests for polymorphism revealed several duplication events. Out of a set of 33 SSR markers
that could be integrated in an RFLP linkage map of Brassica napus, 21 were members
of this group of primer pairs representing several loci. Rosabelle Samuel1, Tod Stuessy1, Karin Tremetsberger1, Walter Gutterman2 & Sonia Siljak-Yakovlev3 1Department of Higher Plant
Systematics and Evolution, Institute of Botany, University of Vienna, Rennweg 14, A-1030
Vienna, Austria Talk — Nuclear internal transcribed spacer region (ITS) and chloroplast trnL intron and trnL/trnF spacer and matK sequences were used to assess relationships among European and South American species of Hypochaeris plus some species of Leontodon and other related genera of tribe Cichorieae. ITS tree shows high resolution compared to that of the maternally inherited trnL/F and matK genes. ITS and combined tree reveal clades that agree well with sections of the genus Hyphochaeris established previously on morphological and cytological grounds except for H. robertia. The taxonomic position of H. robertia still remains questionable. Lower levels of sequence divergence among South American taxa suggest a pattern of rapid speciation, in contrast to much greater divergence among European representatives. Nuclear ITS sequences reveal that Leontodon is paraphyletic, supporting the morphological classification of Widder (1975) and Finch and Sell (1976). Leontodon, Picris and Helminthotheca are very closely related to each other as well as to Hypochaeris. Polyploid formation and establishment in bryophytes Sigurd M. Sĺstad Department of Natural History, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway Talk — Growing evidence from molecular data demonstrate neopolyploid origin in bryophytes. However, we lack empirical data on important stages of the pathways potentially important for polyploid formation in this group of plants. Hence, questions regarding commonness of various types of polyploids (allopolyploids and autopolyploids) and mode of formation (apospory versus diplospory) remain unsettled. Models developed for polyploid evolution in seed plants are not directly applicable to bryophytes because of important differences in their life cycles. Bryophytes are unique among land plants in that the gametophyte is the longer lived, autonomous and more photosynthetically active generation. The gametophyte also has a high potential for vegetative reproduction; in principal every cell may regenerate into a new individual. In this presentation I review the current knowledge of polyploid evolution in bryophytes, and assess the processes of polyploid formation and establishment in light of the bryophyte life cycle. Evolutionary radiations in plants: case studies in South Africa and South America V. Savolainen1, M. Perret2, A. Chautems2, P.Goldblatt3, J. Manning4, M. Powell1, M. van der Bank5, T. Barraclough6 & M.W. Chase1 1Royal Botanic Gardens, UK Invited talk — Species-level phylogenetic trees allow the evaluation of various hypotheses for the origin of species diversity. Two case studies will be discussed: Neotropical Gesneriaceae and the African peacock irises Moraea. For nearly all species in the three genera of tribe Sinningieae (Gesneriaceae), Sinningia, Paliavana, and Vanhouttea (mostly in southeastern Brazil) six non-coding DNA regions and several intron in nuclear plastid-expressed glutamine synthetase gene (ncpGS) were sequenced. Separate and combined analyses of these data sets using maximum parsimony supported the monophyly of Sinningieae, but the genera Paliavana and Vanhouttea were found embedded within Sinningia; therefore a new infrageneric classification is here proposed. Mapping of pollination syndromes on the DNA-based trees supported multiple origins of hummingbird and bee syndromes and derivation of moth and bat syndromes from hummingbird flowers. Perennial tubers were derived from perennial stems in non-tuberous plants. Phylogenetic analyses of four plastid DNA regions from each of 163 species in the African genus Moraea (Iridaceae: Irideae) including accessions of all major species clusters in the genus, show Moraea to be paraphyletic when Barnardiella, Galaxia, Hexaglottis, Homeria (all southern African), and Gynandriris (Eurasian as well) were recognized as separate genera. There are several small, isolated species clusters at the basal nodes of the tree that are all restricted to the winter-rainfall zone of southern Africa (the Greater Cape floral kingdom) and a few, highly derived, large species groups that have radiated extensively within the winter-rainfall zone. Mapping of floral traits shows that an Iris-type flower is ancestral in Moraea. Floral changes are associated with shifts in pollination systems, either from passive pollen deposition on long-tongued bees foraging for nectar to active pollen collection by female bees foraging for pollen, fly, or hopliine scarab beetle pollination. Dating the nodes of the phylogenetic tree using non-parametric rate smoothing with a calibration point derived from broad dating of the angiosperms indicates that the divergence between Moraea and its sister genus Ferraria occurred about 25 mya in the early Miocene. The early radiation of Moraea took place against a background of aridification and the spread of open habitats, such as desert, shrubland, and fynbos. Gene Genealogies and Phylogeography in Plant Populations Barbara Schaal Department of Biology, Washington University, St. Louis, MO 63130, USA Invited talk — The distribution of genetic variants in plant populations is strongly affected by both current patterns of microevolutionary forces, such as gene flow or selection, and by the phylogenetic history of populations and species. Understanding the interplay of shared history and current evolutionary events is particularly confounding in plants due to the reticulating nature of gene exchange between diverging lineages. The development of rapid DNA sequencing methods has provided an important tool for analyzing the standing distribution of genetic variation within species and for determining the relative importance of adaptive evolution versus other processes. Gene sequences provide historically ordered neutral molecular variation that can be converted to gene genealogies which trace the evolutionary relationships among haplotypes (alleles). Gene genealogies can be used to understand the evolution of specific DNA sequences and relate sequence variation to plant phenotype. For example, in a study of the RPS2 gene in Arabidopsis thaliana, resistant phenotypes clustered in one portion of the gene tree. The field of phylogeography examines the distribution of allele genealogies in an explicit geographical context and, when coupled with a nested clade analysis, can provide insight into historical processes such as range expansion, gene flow, and genetic drift. We have used a phylogeographical approach to understand the relative effects of gene flow and range expansion in the evolution of native pine species in Asia. Phylogeographic studies can also offer insight into practical issues as well, such as the domestication process in crops, and the origin of invasive weeds. Plant speciation modes in Amazonia with special reference to the Melastomataceae Leif Schulman1,2 & Kalle Ruokolainen1 1Section for Biodiversity and
Environmental Science, Department of Biology, FIN-20014 University of Turku, Finland Talk — Due to overemphasis during the last three decades on the Pleistocene Refuge Hypothesis and the allopatric speciation mode in general, alternative speciation models have hardly been explored in Amazonia. In recent years the constellation has changed. The refuge hypothesis has met with strong opposition. Theoretical and empirical studies have shown that sympatric divergence is a tenable alternative to allopatric speciation. Local genetic differentiation driven by natural selection has been estimated to play a central role in plant speciation. Studies on plant speciation have proven that several evolutionary phenomena enabling sympatric speciation occur in plants. In Amazonia, analytical studies on speciation modes are nevertheless almost non-existent. It has been pointed out that allopatric models cannot easily account for all diversity and distributional patterns found in Amazonia, but these claims have been based simply on field observations. The question is difficult to tackle due to a lack of taxonomic, biogeographical, ecological, and phylogenetic information on Amazonian plants. Here I present two case studies in the Melastomataceae that focus on speciation modes. In the first, the best available taxonomic and distributional information was used to pick a sympatric pair of supposed sibling species in the genus Clidemia. The species, C. epiphytica and C. longifolia, were collected in three areas in western Amazonia. The morphology of the specimens was analysed and compared to ecological data collected on the same sites. The results showed that the taxa most probably are two separate biological species that occur in sympatry but are ecologically separated (grow in different habitats). The most parsimonious explanation for these results is that they have diverged sympatrically. In the second case, a phylogeny was constructed for the predominantly Amazonian genus Adelobotrys. Sibling taxon pairs were selected from the phylogeny for a biogeographical comparison. This revealed a mixed signal: some of the pairs were clearly allopatric, others sympatric, and some parapatric. Some of the sympatric cases were selected for an ecological comparison. In a couple of cases clear habitat partitioning was found, suggesting that these may be examples of sympatric speciation through ecological specialisation. Both studies thus point to possible cases of non-allopatric speciation, but they provide only circumstantial evidence. However, only the existence of good candidate cases renders feasible deeper studies on mechanisms that could have caused a breach in gene flow between two ancestral populations and hence enabled speciation. The next step in the search for actual cases of non-allopatric plant speciation in Amazonia could be to study the reproductive biology and genetics of some of the candidate cases revealed in the current studies. Federico Selvi1, Massimo Bigazzi1, Alessio Papini1 & Hartmut H. Hilger2 1Dipartimento di Biologia Vegetale
dell’Universitŕ, Via G. La Pira 4 I-50121 Firenze, Italy Poster — Nonea Medik. is one of the
core genera of the Boraginaceae tribe Boragineae, and consists of about 40 taxa
distributed in the Tethyan region from Western Asia to Morocco and the Iberian peninsula,
with a centre of diversity between the Pontic-Caucasian mountain system and the Eastern
Anatolian highlands. Fewer species occur in Europe and in the Mediterranean, especially
along the North African coast. Polyploidy and hybridisation in the Australian Salicornioideae (Chenopodiacea) Kelly Shepherd & Guijun Yan School of Biology, Faculty of Natural and Agricultural Sciences, The University of Western Australia, Crawley, WA 6009, Australia Talk — The subfamily Salicornioideae Dumort
comprises the halophytic, succulent herbs and subshrubs of the Chenopodiaceae Venten.
characterised by articulated leafless stems and a spike-like inflorescence. Australia has
a significant proportion of the world’s diversity of the subfamily with a total of
six genera; Halosarcia Wils., Pachycornia Hook.f., Sarcocornia,
Sclerostegia Wils., Tecticornia Hook.f and Tegicornia Wils., 36
species and 13 subspecies currently recognised, the majority of which are endemic. Despite
the diversity of Salicornioideae present in Australia no previous chromosome counts have
been reported. This study documents new somatic chromosome counts from 27 accessions
representing 21 Australian species across six genera. These data reveal that the
Australian Salicornioideae have a basic chromosome number of x = 9, which is congruent
with other members of the Chenopodiaceae and polyploidy is evident ranging from diploid to
hexaploid (2x = 18, 27, 36 and 54). Petr Smarda Department of Botany, Faculty of science, Masaryk University, Kotlá_ská 2, CZ-611 37 Brno, Czech Republic Poster — The primary aim of this project was
a thorough karyological and morphological investigation of central European taxa of Festuca
ser. Psammophilae M. Pawlus (F. pallens Host, F. psammophila
(Celak.) Fritsch, F. vaginata Willd.).The study area includes Germany, the Czech
and Slovak Republics, Southern Poland, Austria and Hungary. Species level phylogenetics in the monocot family Costaceae: rapid radiation and floral evolution Chelsea D. Specht1, 2 & Dennis W. Stevenson1 1New York Botanical Garden, Bronx, NY
10458, USA Talk — A cladistic analysis of molecular and morphological data for a representative taxonomic sampling of Costaceae reveals that a revision of the taxonomy is necessary in to reflect phylogenetic relationships. In addition, characters typically used to define ‘natural groups’ within Costaceae are actually homoplasious, and their historical use to define taxonomic groups has resulted in the recognition of various polyphyletic genera and subgenera. Many of these defining characters are actually suites of characters, often associated with pollination syndromes. An analysis of character evolution has revealed that while many of these composite characters are homoplasious, the individual characters that comprise them provide morphological synapomorphies for monophyletic lineages. A major clade is recovered that is comprised of those new world species with inflorescence structures closely associated with pollination syndrome (either bird or bee-specific pollination). This clade appears to have undergone rapid radiation based on molecular data. Potential mechanisms involved in the apparent rapid speciation will be discussed. Phylogenetics of the Aizoaceae and its correlation with life strategies and photosynthetic types Joachim Thiede & Maik Veste Hamburg University, Botanical Institute, Ohnhorststr. 18, D-22609 Hamburg, Germany The results of a molecular phylogenetic study of the Aizoaceae and related families (Molluginaceae, Gisekiaceae, Phytolaccaceae, Petiveriaceae, Nyctaginaceae) based on non-coding internal transcribed spacer (ITS 1 & 2) sequence data of the nuclear ribosomal DNA are presented. The phylogenetic data data are interpreted on three levels: 1. Systematic implications: 2. Correlation of phylogenetic patterns with
life strategies 3. Correlation of phylogenetic patterns with
photosynthetic types In summary, the phylogenetic data for the Aizoaceae provide evidence for strong correlations between phylogenetic position, life form and life strategy, and mode of photosynthesis. Origins and history of polyploid species: what DNA variation can and can not tell us P. H. van Tienderen & J.C.M. den Nijs Experimental Plant Systematics, Institute for Biodiversity and Ecosystem Dynamics (IBED), Kruislaan 318, University of Amsterdam, 1098 SM Amsterdam Invited talk - It is estimated that 50-70 per
cent of flowering plants have polyploid ancestors. Polyploidy is also of prime importance
in speciation, since new polyploids are often immediately isolated from their ancestors
due to hybrid infertility. In fact, it could be argued that if the biological species
concept it used, polyploidy is an example of instant sympatric speciation. The isolation
of the parental lineages implies that they can undergo independent further evolution,
after the initial formation of the polyploid that already may differ in morphology and
ecology from its parents.
We will argue that some of the above questions can indeed be studied using DNA variation, but that reticulate patterns and concerted evolution may easily blur any pattern. Karin Tremetsberger1, Salvador Talavera2, Tod Stuessy1, Maria Angeles Ortiz2, Hanna Weiss1 & Gertrud Kadlec1 1Department of Higher Plant
Systematics and Evolution, Institute of Botany, University of Vienna, Rennweg 14, A-1030
Vienna, Austria Talk — Hypochaeris salzmanniana has been described by A.P. de Candolle in 1838 from material collected by Salzmann in Tánger (NW Morocco). Most authors have related H. salzmanniana to H. glabra and have included it as a variety, subspecies, or simply as a synonym of H. glabra L. On the basis of morphological and cytological characters, Talavera (1980, 1987) separated H. salzmanniana from H. glabra. The two species can be distinguished clearly by H. glabra with 4–7 mm long ligules, barely exserted from the involucre, and H. salzmanniana with 16–20 mm long ligules, conspicuously exserted from the involucre. Hypochaeris glabra chromosomally is 2n = 10 and H. salzmanniana 2n = 8 (as is also H. radicata). Hypochaeris salzmanniana is restricted to coastal dunes on both sides of the Straits of Gibraltar. The aim of our study was to provide molecular evidence for the taxonomic status of H. salzmanniana and its relationship to H. radicata, and to assess the populational structure of H. salzmanniana with correlations to biogeographic history. Material has been collected from Spain, Italy, and Tunisia and analyzed by Amplified Fragment Length Polymorphism (AFLP). Six selective primer combinations have been used to obtain bootstrap values supporting three well differentiated species (100% BS for H. glabra and H. salzmanniana and 52% BS for H. radicata). Out of 334 scored fragments, H. salzmanniana is differentiated from H. glabra by 95 and from H. radicata by 55 diagnostic fragments. A closer relationship of H. salzmanniana and H. radicata, therefore, is confirmed by AFLP data. Based on DNA sequence data (Samuel et al., in press), the age of origin of Hypochaeris section Hypochaeris has been estimated at the end of the Tertiary, with a more recent evolution of H. radicata from H. salzmanniana being hypothesized. The populational structure of H. salzmanniana reveals three geographically distinct subpopulations: those from Costa de la Luz along the Atlantic Ocean forming a panmictic subpopulation, of which one population grows on a fossil dune c. 1 km inland; a population near Tarifa c. 15 km W of the Straits of Gibraltar, also facing the Atlantic Ocean, forms a second subpopulation also on a fossil dune system; finally, populations near Gibraltar facing the Mediterranean Sea form a third subpopulation. The population from near Tarifa is particularly divergent and has low within-populational variation, supporting its presumptive relict nature. Andreas Tribsch1 & Peter Schönswetter2 1Institute of Botany, Department of
Systematics and Evolution, University of Vienna, Rennweg 14, A-1030 Vienna, Austria Talk — Simultaneously to the worldwide
cooling of the climate in the late Tertiary, the uplift of the Alps started (upper
Miocene, c. 6 my BP) enhancing the evolution of taxa adapted to the newly formed alpine
biome. Central Asian, Mediterranean and later on Arctic elements contributed to the
formation of the rich Alpine flora present today. Approximately 2 my BP the dramatic
Quaternary climatic fluctuations started and recurrent glaciations restricted the biota to
ice-free and climatically favourable refugia. Until today, patterns of endemism exhibit
high correlation to these formerly unglaciated or weakly glaciated areas. The isolation in
refugia during cold stages as well as refugial situations during warm periods of the
Quaternary were important factors in the evolution and radiation of alpine plants. The application of Bayesian techniques in biogeography Hubert Turner Theoretical Biology and Phylogenetics, Institute of Evolutionary and Ecological Sciences, Leiden University, PO Box 9516, 2300 RA Leiden, The Netherlands and National Herbarium Nederland, Leiden branch Invited talk - One of the prominent differences between Bayesian Inference and ‘regular’ Maximum Likelihood analysis of phylogenetic trees, is that BI marks a domain in treespace as a 95% confidence interval containing the correct tree. Usually this set of trees is summarized as a majority-rule consensus tree. However, it is questionable whether such consensus trees are the most appropriate starting point for the reconstruction of a general area cladogram: the majority-rule topology may not be among the tree topologies in the set of original trees. In the ideal case, all clades in an analysis have reacted to the same area history, and thus, the true phylogenetic tree for each clade should be convertible to the true area cladogram. Of course, the true phylogeny is not known, but the set of trees produced by Bayesian Inference probably contains this tree. When several clades are used to reconstruct a general area cladogram, the true area cladogram should lie in the intersection of the sets of area cladograms derived from all tree topologies for each clade. The cladogram topologies giving rise to the area cladograms contained in the intersection do not necessarily contain any of the bipartitions of the majority-rule trees for their respective clades. This is a second argument why majority-rule consensus trees should not be used here. Because it is very impractical and time-consuming to construct an area cladogram for each tree topology in every clade’s set of trees, I propose an approximation here. When reconstructing a majority-rule consensus tree using PAUP*, the program can at the same time produce a list of all observed bipartitions. Each bipartition can be converted to a potential bipartition for an area cladogram, by computing the inner Boolean product of the (taxon * node) matrix of bipartitions with the (area * taxon) matrix of distributions. This results in an areas * node matrix, which can be used to reconstruct an area cladogram. Applying this procedure to a single clade will result in an areas* nodes matrix which gives the area cladogram derived from the majority-rule consensus tree, because the bipartitions of the m-r consensus reappear with the same frequency in the areas * node matrix. However, when constructing an areas * node matrix for a general area cladogram reconstruction, hypothetically the frequency of the erach bipartition of the true area cladogram is the sum of the frequencies with which it appears among the sets of trees for the separate clades. Just like in parsimony reconstructions homoplasy is random but true synapomorphies reinforce each other, in the approach described here true bipartitions are reinforced by their appearance in all sets of cladograms, while individual clade’s deviations from the ‘true’ vicariance pattern result in bipartitions that are not replicated by other clades’ sets of cladograms. As an example the reconstruction will be demonstrated of a general area cladogram for Sundaland using Bayesian Inference results for two clades, Coelogyne (Orchidaceae), and Macaranga (Euphorbiaceae). Alain Vanderpoorten*, A. Jonathan Shaw & Cymon J. Cox Department of Biology, Duke University, Durham, USA * current address: Unité d'Ecologie & Biogéographie, Université Catholique de Louvain, Belgium Talk — Maximum likelihood analyses of DNA sequences from two chloroplast regions, trnL-trnF and atpB-rbcL, and the internal transcribed spacers of 18S-5.8S-26S rRNA gene array, were performed to resolve species relationships within the moss genus Amblystegium. Although monophyly of one morphospecies could be significantly rejected, the lack of support for most clades and the partial incongruence among topologies, necessitated the use of another independent, more variable region, namely the adenosine kinase gene (adk). Sequences for adk were polymorphic but were present as multiple copies within individuals, making parology a problem for phylogenetic analyses. Multiple adk gene copies appear to have evolved in these polyploid species of Amblystegium. Adk evolution was reconstructed using a reconciled gene tree approach in which duplications and losses were minimized in the context of a species tree, assumed to be true, derived from the cpDNA and nrDNA data. Additional resolution of the species tree was then obtained by searching for reconstructions that further reduced adk duplications and losses. The final tree supported a monophyletic interpretation of A. serpens, but the other morphospecies appeared polyphyletic. Together with previous data from different molecular markers, the results support the interpretation that Amblystegium represents a recent radiation in which molecular and morphological evolution have been uncoupled. Radim J. Vašut1,2 & Bohumil Trávnícek1 1Department of Botany, Faculty of
Science, University of Palack_, _lechtitel_ 11, CZ–78371 Olomouc, Czech Republic Poster — Microspecies delimitation within
Taraxacum sect. Erythrosperma (H. Lindb.) Dahlst. was studied to investigate
the distribution of sexual diploids (2n=16, T. erythrospermum) and apomictic
polyploids (mostly triploids) at the western margin of the Pannonian Basin (SE Czech
Republic, NE Austria, W Slovakia). For this area, several species have repeatedly been
cited in the literature that were known from N and NW Europe (e. g. T. proximum, T.
disseminatum, T. isophyllum), but critical studies were lacking. We studied
morphological variation, ecological behaviour and plasticity of plants in about 250
natural populations. Flow-cytometric analyses for discriminating the sexual diploids and
apomict polyploids revealed a total of 21 different apomictic clones. Most of the species
known from the literature appeared to be rare or (almost) absent. It seems that newly
distinguished microspecies represent similar but different clones to western European
ones. In a mixed dandelion populations of T. sect. Ruderalia and T.
sect. Erythrosperma putative interspecific hybrids were found, but further
investigation is required. Genetic fine-maping of apomixis elements in Taraxacum officinale auct. Radim J. Vašut1, Marcel van Culemborg2, Erik Wijnker1, Peter J. van Dijk2 & J. Hans de Jong1 1Laboratory of Genetics, Wageningen
University, Arboretumlaan 4, 6703 BD Wageningen, The Netherlands Poster — In order to better understand the biology of apomixis in natural Taraxacum populations we started a long term project on its genetic control. Genetic analyses of crosses between diploid sexual and triploid apomicts demonstrated that apomixis in Taraxacum is genetically controlled by at least three (elements), i.e., diplospory, parthenogenesis and autonomous endosperm development. Phenotyping of the different recombinants was carried out with Nomarski microscopy of cleared whole mount female organs. The present study aims at seeking for molecular markers linked to diplospory in a population of 193 offspring individuals. Here we present a construction of linkage groups with 10 microsatellites (SSRs) using the software package JoinMap®. Two markers were found to be linked to diplospory and a third one was found to be linked to parthenogenesis. Additional mapping of at least 16 more microsatellite and numerous AFLP markers for fine mapping of the parthenogenesis gene are in progress. Molecular markers reveal cryptic species and reproductive isolation within Polytrichum commune s.l. Marco van der Velde, Anneke C. Boerema, Louis van de Zande, Ben O. van Zanten & R. Bijlsma Department of Genetics, University of Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands Talk — Based on morphological characters
only, the taxonomy of the bryophyte genus Polytrichum has still not been fully
resolved. Nowadays, molecular genetic methodologies are available that can help to clarify
some of these problems. Within P. commune s.l., the taxonomic status of several
varieties, e.g. P. commune var. commune and P. commune var. uliginosum,
is still debated. Allozyme electrophoresis revealed that there are two distinct
multi-locus genotypes within our European P. commune samples, which coincide with
differences in both morphology and habitat association. In addition, these allozyme data
showed that the level of genetic differentiation between P. commune var. commune
and P. commune var. uliginosum is of the same order of magnitude as
generally is observed among congeneric moss species. Based on these results, we argue that
these two infraspecific taxa of P. commune s.l. should be regarded as distinct
species: P. commune and P. uliginosum. The ephemeral nature of polyploidy: Patterns and processes of evolution in European Asplenium Johannes Vogel1, Stephen Russell1, Michael Grundmann1, Fred Rumsey1, Harald Schneider2, 3, Mary Gibby4 & John Barrett5 1Department of Botany, Natural History
Museum, SW7 5BD London, UK Invited talk - The "success" of
polyploid plants in relation to their diploid progenitors is attributed to their ability
to maintain higher levels of heterozygosity, in expressing less inbreeding depression and
their often polyphyletic origins. This mode of formation incorporates genetic diversity
from multiple progenitor populations into the polyploid "species", thus leading
to a broad sampling of ancestral diversity into the polyploid gene pool. Miriam Vogel, Gudrun Bänfer & Kurt Weising Plant Molecular Systematics, FB19 Biologie/Chemie, Universität Kassel, D-34109 Kassel, Germany Talk — As part of our ongoing study on speciation processes in the paleotropic ant-plant genus Macaranga, we have initiated a phylogeographic analysis based on chloroplast haplotypes. To screen for size-variable DNA regions in the Macaranga chloroplast genome, we initially applied ten universal PCR primer pairs described by Weising and Gardner (Genome 42: 9–19, 1999) to a small set of specimens, covering various taxonomic levels from intrafamilial (several genera of Euphorbiaceae) to intraspecific (several specimens of various Macaranga species). Eight primer pairs produced PCR fragments that behaved as single, discrete, and size-variable bands after separation on agarose gels. The 5 most promising candidate pairs were further analysed with an extended set of DNA templates, and PCR products were separated on a LICOR fluorescence sequencer, allowing single-base resolution. Variation was detected within several Macaranga species, with up to 4 different haplotypes among 6 conspecific specimens. Comparative sequence analysis of the PCR products showed that microsatellites were responsible for the observed size variation at three of the five loci sequenced. In addition to (A)n/(T)n repeats which are typically found in chloroplast DNA, we also identified a variable (CT)n-repeat., with n=4 to n=8. These polymorphic cpDNA markers will now be applied to analyze the geographic distribution of haplotypes in two myrmecophytic Macaranga species, i.e. M. indistincta and M. pearsonii. Domain directed profiling; a glance at molecular evolution Ben Vosman, Gerard van der Linden & René Smulders Plant Research International, PO Box 16, 6700 AA Wageningen, The Netherlands Invited talk — Genetic diversity at or below
the species level use is mostly characterized with supposedly neutral markers. This type
of marker is very effective for a wide range of applications including the establishment
of the breeding system, the study of gene flow, and the reconstruction of phylogenies.
However, ‘users’ of biodiversity are not interested in neutral variation but
rather in variation that might affect the evolutionary potential of a species or the
performance of an individual variety. Therefore several routes are exploited to
characterize species for ‘functional’ variation. Phenotypic variation is tagged
with molecular markers using QTL and LD-mapping approaches, as well as domain directed
DNA-profiling techniques. Palaeogeographic affinity of the Permian Jambi flora from Sumatra I.M. van Waveren, J.H.A. van Konijnenburg-van Cittert & R.H. Wagner National Museum of Natural History, Naturalis, Leiden, The Netherlands Poster — At Naturalis we are revising the
main genera from the Jambi flora (Jongmans & Gothan, 1936) from the Lower Permian of
Sumatra (Indonesia). This revision will enable us to compare the Jambi flora with more
recent work on Permian South East Asian floras from Shansi (China), Thailand, Malaysia and
from Australia. The relationships of Sauropus (Euphorbiaceae), a call for a molecular phylogenetic analysis Peter C. van Welzen Nationaal Herbarium Nederland, Universiteit Leiden branch, P.O. Box 9514, 2300 RA Leiden, The Netherlands Poster — Sauropus is a relatively
large genus of c. 60 species. Its distribution ranges from India throughout SE Asia and
the Malay Archipelago to Australia. There are two centres of diversification, one in
Thailand and Indochina, the other in Australia. The representatives of Sauropus in
Australia were formerly classified in a separate genus, Synostemon. Former Synostemon
has one wide-spread representative in SE Asia: S. bacciformis. Evolution of the ginseng genus: geographic disjunctions, rapid radiations, and polyploidy Jun Wen & Chunghee Lee Department of Botany, Field Museum of Natural History, 1400 S. Lake Shore Dr., Chicago, IL 60605, USA Talk — Panax L. (the ginseng genus, Araliaceae) is medicinally important in Asia. Various molecular markers have been employed to help delimit taxa, elucidate the evolutionary relationships, detect evolutionary patterns, and contruct the biogeographic history for the genus. The taxonomy of Panax has been highly controversial. Biogeographically Panax shows a classical disjunct distribution between eastern Asia and eastern North America. In this study, we have used sequences of the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA, and the chloroplast ndhF gene and the trnC – trnD intergenic spacer, and chloroplast DNA restriction site variation. Our analyses indicate two independent intercontinental disjunctions between Asia and North America in the ginseng genus. The first is ancient, involving the eastern North American P. trifolius, and the Sino-Himalayan P. pseudoginseng – P. stipuleanatus. The second disjunction is suggested to have occurred in the late Tertiary, involving the eastern North American P. quinquefolius and the eastern Asian P. ginseng – P. japonicus. Comparisons of the nuclear and chloroplast DNA data suggest that Panax bipinnatifidus and P. major are autotetraploids, each taxon has arisen independently multiple times. Our data suggest that the Asian species of Panax have experienced a rapid radiation in the Sino-Himalayan region. Fourteen species are currently recognized within Panax based on the morphological and phylogenetic evidence. Genes, jeans and genomes: insights from the cotton genus Jonathan Wendel Department of Botany, Iowa State University, Ames, IA 50011, USA Invited talk — The cotton genus (Gossypium) includes approximately 50 species with a global distribution in arid to semi-arid regions of the tropic and subtropics. Gossypium species exhibit extraordinary morphological diversity, ranging from herbaceous perennials to small trees and having a great variety of floral and vegetative features. A parallel level of cytogenetic and genomic diversity has evolved during the global radiation of the genus, and DNA content varies over three-fold among the diploid species. Four species have independently been domesticated for their fiber, two each in the Old and New World. Molecular phylogenetic studies have clarified the evolutionary history of Gossypium, including its origin 5–15 million years ago. Speciation in the genus has been facilitated by multiple episodes of trans-oceanic dispersal, invasion of new ecological niches, acquisition of specialized reproductive syndromes, and a surprisingly high frequency of natural interspecific hybridization among lineages that presently are inter-sterile. Allopolyploid Gossypium emerged from a chance merger of two genomes that vary two-fold in size and evolved in isolation for millions of years. This remarkable biological reunion has led to novel genomic interactions, a high frequency of gene silencing, and possible functional differentiation among homoeologues. Polyploidy also is suggested to have opened up new avenues for agronomic improvement. Bikinia and Tetraberlinia (Fabaceae): old sisters or recent Siamese twins? Jan J. Wieringa Nationaal Herbarium Nederland, Wageningen University branch, Generaal Foulkesweg 37, 6703 BL Wageningen, The Netherlands Talk — Recent morphological and molecular
studies on Bikinia and Tetraberlinia (Detarieae s.l., Macrolobieae-clade)
show that these two genera constitute a single clade. However, whether both genera are
monophyletic remains to be seen. Bikinia species share a fair amount of
synapomorphologies, both in morphological and molecular datasets, and form without to much
doubt a monophyletic group. The only doubt so far on the monophyly of Bikinia
originates from the existence of the monotypic genus Icuria from Mozambique. Some
morphological evidence and ITS sequences put this genus inside the Bikinia clade,
while other sequences suggest it is more closely related to some other genera of the
Macrolobieae clade, especially Aphanocalyx. Tetraberlinia on the other hand
lacks strong evidence for its monophyly, phylogenetic studies place it either as sister to
Bikinia or show Bikinia as derived from within it. Niklas Wikström Department of Botany, The Natural History Museum, London SW7 5BD, UK Invited talk — The documentation of derived angiosperm lineages from increasingly older geological deposits, and growing evidence of considerable diversity in flower, seed, and pollen morphology in the mid Cretaceous both imply that the timing of early angiosperm cladogenesis may be older then our current fossil-based estimates indicate. An alternative to fossils for calibrating the phylogenetic tree comes from divergence in DNA sequence data. Here, we report on an analysis using non-parametric rate smoothing and a three-gene data set covering c. 75% of all angiosperm families recognized in recent classifications. The results provide an initial hypothesis of angiosperm diversification times and by using an internal calibration point, an independent evaluation of angiosperm and eudicot origins is accomplished. Results are compared to fossil-based estimates of both magnolids and eudicot divergence times, and possible directions of future analyses are discussed. Volker Wissemann Friedrich-Schiller-Universität Jena, Institut für Spezielle Botanik, Philosophenweg 16, D-07743 Jena, Germany Talk — Hybridisation in plants is – in
general – regarded as a relatively frequent and spanning factor of plant evolution.
This frequency inveigles towards a comprehensive view of hybridisation but points out to
be misleading by going into detailed hybrid analysis. If just looking at numbers, more or
less 50% of all higher plants are assumed to be of hybrid origin, but hybridisation is not
evenly distributed among plants. Certain families like Rosaceae, Asteraceae, Poaceae or
Orchidaceae form the core groups of hybridisation processes, whereas other groups seem to
be not ‘susceptible’ for hybridisation, or have not been studied thoroughly. Posthybridogenic evolution of nuclear ribosomal ITS-sequences Volker Wissemann Friedrich-Schiller-Universität Jena, Institut für Spezielle Botanik, Philosophenweg 16, D-07743 Jena, Germany Poster — Hybridisation plays a significant
role for the evolution and speciation of plants. Nevertheless the knowledge about
frequency and importance of reticulate evolution in plants in an overall view is limited
for a variety of reasons ranging from theoretical biases to practical-technical problems
of experimental hybrid detection. This presentation focusses on the evolution of the
nuclear ribosomal Internal Transcribed Spacer (nrITS) region following hybridisation and
the potential use for detection and analysis of hybridisation patterns in plant evolution. Yoko Yatabe & Noriaki Murakami Department of Botany, Faculty of Science, Kyoto University, 606-8502, Sakyou, Kyoto, Japan Talk — Cytotaxonomical and enzyme electrophoretic data have discovered several cryptic species in various lineages of homosporous ferns (Paris et al., 1989). Chloroplast DNA sequences may provide us with favourable information because of its advantageous feature as a molecular marker. We examined rbcL sequences in various fern species and found a large amount of variations among conspecific materials. Considering the slow evolutionary rate of rbcL, the large amount of rbcL sequence variation within a single morphological species may suggest that it contain several cryptic species. Especially, in bird-nest fern, Asplenium nidus sensu Holttum (1974), the difference of rbcL sequences between most distantly related individuals reached 4-5%. In the sympatric populations of A. nidus of Mt. Halimun National Park, West Java, Indonesia, we found five rbcL sequence types. Based on the molecular phylogenetic analysis with plants from other localities, the five rbcL types from West Java were not closely related to each other. In order to test the hypothesis that the assemblages of A. nidus delimited based on the rbcL sequences are separate Mendelian populations and gene flow is disrupted by reproductive isolation one another, we examined allozyme polymorphism of the populations in West Java. As the result, these rbcL types were genetically differentiated also in their nuclear genomes, and our hypothesis was supported. From our ecological observation, it is also suggested that these five rbcL types are differentiated in their habitat preference. Habitats differ among rbcL types with respect to altitude or the position where the plants grow on the tree trunks. Moreover, crossing experiments were performed among various pairs of rbcL types, using the plant materials collected from West Malesiana region, including West Java, and it was revealed that hybrids failed to form between many pairs of the rbcL types. It is suggested that there may exist a lot of cryptic species in Asplenium nidus complex and that rbcL is an efficient first key to find cryptic species. Giuseppe C. Zuccarello1 & John A. West2 1Nationaal Herbarium Nederland,
Universiteit Leiden branch, P.O. Box 9514, 2300 RA Leiden, The Netherlands Talk — The cosmopolitan species group consisting of Bostrychia radicans and Bostrychia moritziana (Ceramiales, Rhodomelaceae), which differ in a single morphological character, shows high levels of inter- and intraspecific genetic variation (up to 10% using plastid-encoded rbcL DNA sequence data). Phylogenetic reconstruction shows seven well-supported and mostly wide-spread lineages. The lineages are reproductively isolated from each other (not zygotes formed) and can be considered as cryptic species. Samples that are evolutionarily divergent, but morphologically identical, can be found in the same locality. Within each of these seven lineages there is also a high level of genetic variation. Calibration of a molecular clock of samples within the most common North American lineage reveals that samples share a recent common ancestor over 12 million years ago. Samples from Pacific Mexico share a closer common ancestor (< 3 million years) to some samples from Atlantic USA then sympatric samples in the Atlantic USA do to each other. Phylogenetic relationships suggest that the distribution of these algae is influenced by recent climatic condition and by range expansion possibly following the last glacial maximum. Hybridization experiments reveal that individuals that differ by as little as 3 base pairs in the plastid encoded RuBisCo spacer are reproductively isolated. Samples from either side of the Americas, are partially compatible, as they produce zygotes forming (carposporophytes) but no meiotic products (tetraspores) are formed. It appears that reproductive isolation forms quickly in these organisms (at least as quickly as our presently most variable molecular marker). This leads to a wide array of reproductively isolated lineages which can ultimately lead to morphological differentiation (morphospecies) and may partially explaining the reason for the species richness of this marine algal division.
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