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One of the most commonly encountered and frequently cited laboratory organisms worldwide is classified taxonomically as Nicotiana benthamiana (Solanaceae), an accession of which, typically referred to as LAB, is renowned for its unique susceptibility to a wide range of plant viruses and hence capacity to be transformed using a variety of methods. This susceptibility is the result of an insertion and consequent loss of function in the RNA-dependent RNA polymerase 1 (Rdr1) gene. However, the origin and age of LAB and the evolution of N. benthamiana across its wide distribution in Australia remain relatively underexplored. Here, we have used multispecies coalescent methods on genome-wide single nucleotide polymorphisms (SNPs) to assess species limits, phylogenetic relationships and divergence times within N. benthamiana. Our results show that the previous taxonomic concept of this species in fact comprises five geographically, morphologically and genetically distinct species, one of which includes LAB. We provide clear evidence that LAB is closely related to accessions collected further north in the Northern Territory; this species split much earlier, c. 1.1 million years ago, from their common ancestor than the other four in this clade and is morphologically the most distinctive. We also found that the Rdr1 gene insertion is variable among accessions from the northern portions of the Northern Territory. Furthermore, this long-isolated species typically grows in sheltered sites in subtropical/tropical monsoon areas of northern Australia, contradicting the previously advanced hypothesis that this species is an extremophile that has traded viral resistance for precocious development.

SummaryOne of the most commonly encountered and frequently cited laboratory organisms worldwide is classified taxonomically as Nicotiana benthamiana (Solanaceae), an accession of which, typically referred to as LAB, is renowned for its unique susceptibility to a wide range of plant viruses and hence capacity to be transformed using a variety of methods. However, the origin and age of LAB and the evolution of N. benthamiana across its wide distribution in Australia remains relatively underexplored.Here, we have used multispecies coalescent methods on genome-wide single nuclear polymorphisms (SNPs) to assess species limits, phylogenetic relationships and divergence times within N. benthamiana.Our results show that the previous taxonomic concept of this species in fact comprises five geographically, morphologically and genetically distinct species, one of which includes LAB.Remarkably, we provide clear evidence that LAB is closely related to accessions collected further north in the Northern Territory; this species split much earlier from their common ancestor than the other four in this clade and is morphologically the most distinctive. Furthermore, this long-isolated species typically grows in sheltered sites in subtropical/tropical monsoon areas of northern Australia, contradicting the previously advanced hypothesis that this species is an extremophile that has traded viral resistance for precocious development.

Background and Aims The extent to which genome size and chromosome numbers evolve in concert is little understood, particularly after polyploidy (whole-genome duplication), when a genome returns to a diploid-like condition (diploidization). We study this phenomenon in 46 species of allotetraploid Nicotiana section Suaveolentes (Solanaceae), which formed Methods We analysed newly assessed genome sizes and chromosome numbers within the context of a restriction site-associated nuclear DNA (RADseq) phylogenetic framework. Key Results RADseq generated a well-supported phylogenetic tree, in which multiple accessions from each species formed unique genetic clusters. Chromosome numbers and genome sizes vary from n = 2x = 15 to 24 and 2.7 to 5.8 pg/1C nucleus, respectively. Decreases in both genome size and chromosome number occur, although neither consistently nor in parallel. Species with the lowest chromosome numbers (n = 15–18) do not possess the smallest genome sizes and, although N. heterantha has retained the ancestral chromosome complement, n = 2x = 24, it nonetheless has the smallest genome size, even smaller than that of the modern representatives of ancestral diploids. Conclusions The results indicate that decreases in genome size and chromosome number occur in parallel down to a chromosome number threshold, n = 20, below which genome size increases, a phenomenon potentially explained by decreasing rates of recombination over fewer chromosomes. We hypothesize that, more generally in plants, major decreases in genome size post-polyploidization take place while chromosome numbers are still high because in these stages elimination of retrotransposons and other repetitive elements is more efficient. Once such major genome size change has been accomplished, then dysploid chromosome reductions take place to reorganize these smaller genomes, producing species with small genomes and low chromosome numbers such as those observed in many annual angiosperms, including Arabidopsis.

International audience; In this review article, we provide an overview of the status of research on Old World Ebenaceae with an emphasis on the large genus Diospyros. The well-supported phylogenetic tree obtained from nucleotide sequences of multiple regions of plastid genome gave clear insights into the subfamilial classification of Ebenaceae. It supported inclusion of previously recognized genera such as Cargillia, Gunisanthus, Maba, Macreightia and Tetraclis in Diospyros. Endemic Diospyros spp. of New Caledonia have multiple origins. One of these clades has c. 21 species that are morphologically distinct and occupy different ecological niches, but they exhibit low genetic variation, leading to a lack of phylogenetic resolution. Analyses of whole plastid genome sequences did not greatly increase resolution or support for results of our previous plastid analyses. Geographical clustering of the individuals against a background of lower sequence divergence of the whole plastid genome could be due to transfer of plastid genomes during hybridization and introgression following secondary contact. However, > 8400 filtered single nucleotide polymorphisms (SNPs) from restriction site associated DNA sequencing (RADseq) confirmed species circumscriptions for this clade and produced well-supported phylogenetic relationships, pointing to an early regional clustering among populations and species. This supported allopatric speciation with respect to macrohabitat (i.e. climatic conditions) having had a role in the initial differentiation in the group. A later, more rapid radiation involved divergence with respect to microhabitat (e.g. soil preference). Although chromosome counts indicate that Diospyros spp. are consistently diploids with 2n = 30, extensive variation in genome size has been observed, which is due to an increase of repeat elements, including LTR/gypsy. In Ebenaceae, pollen is heterogeneous, and palynological synapomorphies are traced at different taxonomic levels. Several new Diospyros spp. have recently been identified and documented from India, Thailand, China, Africa and New Caledonia. Taxonomic revisions have been completed for the Australian species, and synonyms are reported for some New Caledonian Diospyros spp.

Family Anacardiaceae comprises 70 genera and approximately 985 species distributed worldwide. Sri Lanka harbours 19 species in seven genera, among these 15 are endemics. This study focuses on regionally restricted endemics and native Anacardiaceae species, which have not been investigated before at molecular and cytological level. Nuclear rDNA ITS and plastid matK regions were sequenced for ten species, having nine endemics and one native, and incorporated into the existing sequence data for phylogenetic analyses. The topologies resulting from maximum parsimony, maximum likelihood and Bayesian inference are congruent. Family Anacardiaceae forms a monophyletic group having monophyletic subfamily Anacardioideae and paraphyletic subfamily Spondioideae. Tribes Anacardieae, Semecarpeae and Rhoeae form subclades within the major clade of Anacardioideae. All the endemic species occupy correct position in the molecular phylogeny as per the existing classification except for Campnosperma zeylanica, which shows a close relationship to members of the subfamily Spondioideae. The position of non-native species Trichoscypha acuminata also remains unclear. Chromosome counts and karyograms were constructed for five endemic species. The chromosome numbers incorporated in the tree range from 2n = 28–58. Species of tribe Rhoeae have the lowest chromosome number (2n = 24, 28, 30) while species of tribe Semecarpeae have the higher numbers (2n = 50, 52, 58). Chromosome numbers mapped on the phylogeny shows that dysploidy had played a role in the evolution of the species of the family Anacardiaceae in Sri Lanka.

A supra-annual, community-level synchronous flowering prevails in several parts of the tropical forests of Southeast Asia and its evolution has been hypothesized to be linked to pollinator shifts. The aseasonal Southeast Asian lowland rainforests are dominated by Dipterocarpaceae, which exhibit great floral diversity, a range of pollination syndromes and include species with annual and supra-annual gregarious flowering. Phylogenetic relationships within this family are still unclear, especially in the tribe Shoreeae. Here, we develop a pipeline to maximize recovery of genome-wide SNPs from restriction-site associated DNA sequencing (RADseq) in non-model organisms across wide phylogenetic scales. We then infer phylogenomic relationships in the tribe Shoreeae using both traditional and coalescent analyses. The phylogenetic trees obtained with these methods are congruent to each other and highly resolved. They allow reconstructing the evolutionary patterns of floral traits (number of stamens, anther structure and anther/appendage size) in the group. Our inferences indicate that species with many stamens, but smaller, globose anthers and longer appendages and have evolved multiple times from species with fewer stamens, but larger, oblong anthers and shorter appendages. This could have happened in parallel to iterative shifts in pollinators across the uncovered phylogeny from larger, longer generation to smaller, shorter-generation insects that can quickly build up the necessary population sizes during mass flowering episodes.

Origanum (Lamiaceae) comprises a number of essential oil-rich species that have been used by humans for centuries. Today, the four species of section Majorana (O. onites, O. dubium, O. majorana and O. syriacum) are amongst the most widely used. Despite the importance of this section, phylogenetic relationships and species boundaries amongst its four taxa are unclear. In the present investigation, we used DNA sequence data from two nuclear regions [internal transcribed spacer (ITS) and 1-deoxy-d-xylulose 5-phosphate synthase (DXS)] as well as five microsatellite loci to test the taxonomic status of the four species of section Majorana. The combined DNA data revealed O. onites and O. syriacum as the older species in the section. Origanum majorana descends directly from O. syriacum. Origanum dubium was found to be of hybridogenous origin showing attributes of O. onites, O. syriacum and a third, unknown, Origanum species. Both sequence and microsatellite analyses provided evidence for recent hybridization between O. onites and O. dubium in Turkey. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 171, 667–686.

Chromosome counts and genome sizes are reported from six species of Leontopodium: five from the centre of diversity in south-western China, and L. japonicum from cultivation. Previously published chromosome counts for the genus are also compiled. Genome size (1C) in diploids ranges from 0.93 pg (L. dedeckensii) to 1.14 pg (L. cf. stracheyi) and 1.93 pg for tetraploid L. sinense. Leontopodium artemisiifolium had one pair of heteromorphic chromosomes. Leontopodium japonicum accessions showed variation in ploidy levels. Polyploidy, including autopolyploidy, is frequent in the genus. Variation is seen in basic chromosome number, including between species in the centre of diversity of the genus, where x = 12 or 13, but also within species among previously published counts. This variation does not correspond to currently inferred infrageneric groupings, and indicates both the importance of large-scale chromosome evolution and the need for more in-depth taxonomic work in a genus that shows little DNA sequence variation. © 2013 The Linnean Society of London

Background and AimsCapsicum (Solanaceae), native to the tropical and temperate Americas, comprises the well-known sweet and hot chili peppers and several wild species. So far, only partial taxonomic and phylogenetic analyses have been done for the genus. Here, the phylogenetic relationships between nearly all taxa of Capsicum were explored to test the monophyly of the genus and to obtain a better knowledge of species relationships, diversification and expansion. Methods Thirty-four of approximately 35 Capsicum species were sampled. Maximum parsimony and Bayesian inference analyses were performed using two plastid markers (matK and psbA-trnH) and one single-copy nuclear gene (waxy). The evolutionary changes of nine key features were reconstructed following the parsimony ancestral states method. Ancestral areas were reconstructed through a Bayesian Markov chain Monte Carlo analysis. Key ResultsCapsicum forms a monophyletic clade, with Lycianthes as a sister group, following both phylogenetic approaches. Eleven well-supported clades (four of them monotypic) can be recognized within Capsicum, although some interspecific relationships need further analysis. A few features are useful to characterize different clades (e.g. fruit anatomy, chromosome base number), whereas some others are highly homoplastic (e.g. seed colour). The origin of Capsicum is postulated in an area along the Andes of western to north-western South America. The expansion of the genus has followed a clockwise direction around the Amazon basin, towards central and south-eastern Brazil, then back to western South America, and finally northwards to Central America. Conclusions New insights are provided regarding interspecific relationships, character evolution, and geographical origin and expansion of Capsicum. A clearly distinct early-diverging clade can be distinguished, centred in western–north-western South America. Subsequent rapid speciation has led to the origin of the remaining clades. The diversification of Capsicum has culminated in the origin of the main cultivated species in several regions of South to Central America. Fil: Carrizo Garcia, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Barfuss, Michael H. J.. Universidad de Viena; Austria Fil: Sehr, Eva M.. Austrian Institute of Technology; Austria Fil: Barboza, Gloria Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Samuel, Rosabelle. Universidad de Viena; Austria Fil: Moscone, Eduardo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Ehrendorfer, Friedrich. Universidad de Viena; Austria

The phylogeny of the genus Nassauvia and closely related genera was reconstructed using sequences from the internal transcribed spacer regions (ITS) of nuclear ribosomal DNA. The genus Triptilion is nested within Nassauvia, making the latter genus paraphyletic. Neither of the two subgenera Nassauvia and Strongyloma is resolved as monophyletic, and none of the sections of subgenus Nassauvia is recovered as monophyletic. The evolution of the compound secondary inflorescences has been complex in Nassauvia, with the highly aggregated forms representing the original condition in the genus. However, the ancestral condition is equivocal in several clades, and there are alternative reconstructions for the gains–losses of the variously aggregated conditions. There has been at least one gain of solitary capitula in Nassauvia. The evolution of flavonoid chemistry has been complex in Nassauvia, and flavonoids are of limited phylogenetic-taxonomic utility in the genus. Gains–losses of flavonols occur only on terminals whereas changes in flavones and C-glycosyl flavones occur at various levels in the tree. Gains–losses of methylation of flavones and flavonols occur only on terminals., Facultad de Ciencias Naturales y Museo

The genus Leontopodium comprises 30-41 species. The centre of diversity is the Sino-Himalayan region in south-western China, where about 15 species occur. The two species native to Europe, L. alpinum (known as the common 'Edelweiss') and L. nivale, are part of the cultural heritage of the people living there. Despite its importance, very little is known about the systematics of the genus. Because recent molecular studies have shown that species within this genus are closely related and difficult to distinguish with rDNA and cpDNA data, we used AFLPs to obtain a more detailed understanding of the phylogeny of the genus. Our main aims were as follows: (1) to clarify species relationships within the genus; and (2) to reveal information about the biogeography of the genus. We used AFLPs with six primer combinations to investigate 216 individuals in 38 populations of 16 different species. With AFLPs, we were able to recognize 10 different groups, all of which had strong bootstrap support. These results were also congruent with the morphology-based taxonomy of the genus. Most private and rare fragments were found in the Yunnan region (south-western China) relative to Europe and Mongolia/central China, suggesting a long-lasting in situ history of populations in the centre of diversity of the genus. Our results illustrate the utility of AFLPs to resolve phylogenetic relationships between these closely related species.

Amplified fragment length polymorphism (AFLP) markers were used to investigate the relationships among Polystachya accessions from a group of closely related pantropical tetraploids. Before starting with the fingerprinting analyses, the polyploid accessions were first included in a phylogenetic analysis using low-copy nuclear DNA data to establish their relationships, which confirmed that they belonged to a species group of closely related allotetraploids. Neo- and Palaeotropical polyploid accessions formed two hybrid clades with apparently independent origins. Sampling for the AFLP analyses included single accessions from much of the range of the genus and populations from Costa Rica (CR) and Sri Lanka (SL) to compare population structure and genetic diversity in these two areas in more detail. A splits graph of the complete AFLP data showed three major clusters corresponding to three sources of population sampling (P. concreta, SL; P. foliosa ,C R;P. masayensis, CR), with individual accessions from Africa and Indian Ocean islands showing a closer relationship to P. concreta from SL than to the two CR species. Individual accessions from the Neotropics occurred in more isolated positions in the splits network, with little resolution. Some P. foliosa accessions clustered with P. masayensis, suggesting some hybridization between the two species, and this was confirmed by Bayesian structure analysis. However, the splits network, structure and analyses of molecular variance indicated a generally high level of genetic divergence between the two CR species, despite their recent hybrid origin, occurrence in largely the same localities and occasional hybridization. Polystachya foliosa from CR had a higher degree of population-level genetic structure (FST = 0.291) than P. masayensis from CR (FST = 0.161) and P. concreta from SL (FST = 0.138), possibly because of its occurrence within a larger and more environmentally diverse continuous range than the other two species. Genetic divergence between Neo- and Palaeotropical members of the pantropical tetraploid group of Polystachya and the nonmonophyly of P. concreta suggested that P. concreta s.l. should be split and the use of this epithet should be confined to the Neotropics (the type is from Martinique). Other names should be used in Africa and the Asian tropics. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165, 235–250.

The pantropical orchid genus Polystachya comprises approximately 230 species and shows variation in ploidy. For ongoing phylogenetic investigations in this genus, a knowledge of ploidy is necessary. We also looked for a correlation between genome size and guard cell length, so that we could estimate ploidy from preserved material and plants containing high levels of mucilage that are difficult to analyse by flow cytometry (FC). For estimates of ploidy, we measured genome size using FC. For investigations of guard cell lengths and densities, tangential cuts and nail varnish impressions were made. Diploid, tetraploid and hexaploid individuals with genome sizes ranging from 0.58 to 1.80 pg (1C-values) were found. Guard cell length ranged from 15 to 39 µm. The minimum guard cell length was greater in polyploids, but diploid species had a large range of guard cell lengths that encompassed the size range found in polyploids. Although previous studies have found that guard cell length can be used to estimate ploidy in cases in which the genome size range is large, this is not applicable to genera with a small genome size, such as Polystachya. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163, 223–233.

Here evidence for reticulation in the pantropical orchid genus Polystachya is presented, using gene trees from five nuclear and plastid DNA data sets, first among only diploid samples (homoploid hybridization) and then with the inclusion of cloned tetraploid sequences (allopolyploids). Two groups of tetraploids are compared with respect to their origins and phylogenetic relationships.Sequences from plastid regions, three low-copy nuclear genes and ITS nuclear ribosomal DNA were analysed for 56 diploid and 17 tetraploid accessions using maximum parsimony and Bayesian inference. Reticulation was inferred from incongruence between gene trees using supernetwork and consensus network analyses and from cloning and sequencing duplicated loci in tetraploids.Diploid trees from individual loci showed considerable incongruity but little reticulation signal when support from more than one gene tree was required to infer reticulation. This was coupled with generally low support in the individual gene trees. Sequencing the duplicated gene copies in tetraploids showed clearer evidence of hybrid evolution, including multiple origins of one group of tetraploids included in the study.A combination of cloning duplicate gene copies in allotetraploids and consensus network comparison of gene trees allowed a phylogenetic framework for reticulation in Polystachya to be built. There was little evidence for homoploid hybridization, but our knowledge of the origins and relationships of three groups of allotetraploids are greatly improved by this study. One group showed evidence of multiple long-distance dispersals to achieve a pantropical distribution; another showed no evidence of multiple origins or long-distance dispersal but had greater morphological variation, consistent with hybridization between more distantly related parents.

The pantropical orchid genus Polystachya is the subject of ongoing taxonomic work. We inferred phylogenetic relation¬ships in the genus using 5.3 kb of plastid DNA, for 83 out of ca. 240 species and 12 out of 15 sections, as well as five outgroup species. We also collected ploidy data using chromosome counts and genome size estimates. Bayesian and parsimony trees were congruent with each other and well resolved. Polystachya appears monophyletic based on current sampling, provided that the name P. neobenthamia is used instead of Neobenthamia gracilis for that species. The current sectional classification does not define monophyletic groups, but the present study can be used as the basis for a future sectional classification. Areas postulated as Pleistocene refugia for wet tropical forests in Africa also form centres of diversity for the genus. Biogeographical analyses using DIVA and Lagrange show an early radiation in eastern Africa, followed by separate radiations in eastern and western Africa. Subsequent dispersal from western to eastern Africa has occurred at a much higher rate than from east to west. Dispersal to the Neotropics occurred more than once, and one lineage has spread recently and rapidly throughout the tropics. Polyploidy has occurred several times during the diversification of the genus, most notably in association with the recent pantropical dispersal.

It has been hypothesized that annual life history and heterocarpy are an adaptation to unpredictable habitats. In this paper, we infer a phylogenetic history for Scorzoneroides from the analysis of internal transcribed spacer (ITS) and plastid ndhF-rpl32 and rpl32-trnL sequences, on which we trace the evolution of one ecological (predictable vs unpredictable habitats) and two morphological (annual vs perennial and dimorphic vs homomorphic achenes) characters. Our results confirm the monophyly of Scorzoneroides and reveal the existence of two significant evolutionary lineages that do not coincide with major taxonomic subdivisions traditionally proposed for this genus. The first major group comprises taxa with all types of possible combinations of character states. The second major group includes exclusively homocarpic perennial taxa occurring in predictable habitats. It is strongly inferred that the most recent common ancestor of Scorzoneroides was perennial and homomorphic, and occurred in predictable habitats. The evolution of both annual life history and dimorphic achenes was significantly associated with occurrence in unpredictable habitats, which may suggest an adaptation process.

Subfamily Barnadesioideae (Asteraceae) consists of nine genera and 91 species endemic to South America. They include annual and perennial herbs, arching shrubs and trees up to 30 m tall. Presumed sister to all other Asteraceae, its intergeneric relationships are key to understanding the early evolution of the family. Results of the only molecular study on the subfamily conflict with relationships inferred from morphology. We investigate inter- and intrageneric relationships in Barnadesioideae with novel DNA sequence data and morphological characters using parsimony, likelihood and Bayesian inference. All results verify Barnadesioideae as monophyletic and sister to the rest of the family. A basal split within the subfamily is recognized, with Chuquiraga, Doniophyton and Duseniella in one clade, and Arnaldoa, Barnadesia, Dasyphyllum, Fulcaldea, Huarpea and possibly Schlechtendalia in another. The largest genus, Dasyphyllum, is revealed as biphyletic with the two clades separating along subgeneric and geographic lines. Schlechtendalia, suggested as the earliest diverging lineage of the subfamily by morphological studies and parsimony analyses, is found in a more derived position under model-based inference methods. Competing phylogenetic hypotheses, both previous and present, are evaluated using likelihood-based tests. Evolutionary trends within Barnadesioideae are inferred: hummingbird pollination has developed convergently at least three times. An early vicariance in the subfamily’s distribution is revealed. X = 9 is supported as the ancestral base chromosome number for both Barnadesioideae and the family as a whole.

Resupination is the orientation of zygomorphic flowers during development so that the median petal obtains the lowermost position in the mature flower. Despite its evolutionary and ecological significance, resupination has rarely been studied in a phylogenetic context. Ten types of resupination occur among the 210 species of the orchid genus Bulbophyllum on Madagascar. We investigated the evolution of resupination in a representative sample of these species by first reconstructing a combined nrITS and cpDNA phylogeny for a sectional reclassification and then plotting the different types of inflorescence development, which correlated well with main clades. Resupination by apical drooping of the rachis appears to have evolved from apical drooping of the peduncle. Erect inflorescences with resupinate flowers seem to have evolved several times into either erect inflorescences with (partly) non-resupinate flowers or pendulous inflorescences with resupinate flowers.

Background and Aims Some plant groups, especially on islands, have been shaped by strong ancestral bottlenecks and rapid, recent radiation of phenotypic characters. Single molecular markers are often not informative enough for phylogenetic reconstruction in such plant groups. Whole plastid genomes and nuclear ribosomal DNA (nrDNA) are viewed by many researchers as sources of information for phylogenetic reconstruction of groups in which expected levels of divergence in standard markers are low. Here we evaluate the usefulness of these data types to resolve phylogenetic relationships among closely related Diospyros species. Methods Twenty-two closely related Diospyros species from New Caledonia were investigated using whole plastid genomes and nrDNA data from low-coverage next-generation sequencing (NGS). Phylogenetic trees were inferred using maximum parsimony, maximum likelihood and Bayesian inference on separate plastid and nrDNA and combined matrices. Key Results The plastid and nrDNA sequences were, singly and together, unable to provide well supported phylogenetic relationships among the closely related New Caledonian Diospyros species. In the nrDNA, a 6-fold greater percentage of parsimony-informative characters compared with plastid DNA was found, but the total number of informative sites was greater for the much larger plastid DNA genomes. Combining the plastid and nuclear data improved resolution. Plastid results showed a trend towards geographical clustering of accessions rather than following taxonomic species. Conclusions In plant groups in which multiple plastid markers are not sufficiently informative, an investigation at the level of the entire plastid genome may also not be sufficient for detailed phylogenetic reconstruction. Sequencing of complete plastid genomes and nrDNA repeats seems to clarify some relationships among the New Caledonian Diospyros species, but the higher percentage of parsimony-informative characters in nrDNA compared with plastid DNA did not help to resolve the phylogenetic tree because the total number of variable sites was much lower than in the entire plastid genome. The geographical clustering of the individuals against a background of overall low sequence divergence could indicate transfer of plastid genomes due to hybridization and introgression following secondary contact.

With information on fossils and extant distribution of diversity/endemism in the mahogany family, we perform a global biogeographic study of Meliaceae using plastid rbcL data for all subfamilies, tribes and nearly all genera. Our study indicates that: (1) Meliaceae are of western Gondwanan origin; (2) dispersal played an important role for the current distribution of mahogany biota; and (3) the direction of dispersal was most likely an "out-of-Africa" scenario with important dispersal routes across Eurasia and between Eurasia and North America provided by Beringia and the North Atlantic land bridge and North America and South America via island chains and/or direct land connections. Populations in North America, Europe, and East Asia were presumably eliminated as tropical climates disappeared from these areas during the Miocene. Extensive Meliaceae fossil findings confirm that the entry of megathermal (frost-intolerant) angiosperms into southern continents from Oligocene to Pliocene must be considered as an important means of establishing pantropical distribution patterns.

Phylogenetic relationships within tribe Phyllantheae, the largest tribe of the family Phyllanthaceae, were examined with special emphasis on the large genus Phyllanthus. Nuclear ribosomal ITS and plastid matK DNA sequence data for 95 species of tribe Phyllantheae, including representatives of all subgenera of Phyllanthus (except Cyclanthera) and several hitherto unplaced infrageneric groups, were analyzed. Results for ITS and matK are generally concordant, although some species are placed differently in the plastid and ITS trees, indicating that hybridization/paralogy is involved. Results confirm paraphyly of Phyllanthus in its traditional circumscription with embedded Breynia, Glochidion, Reverchonia, and Sauropus. We favor the inclusion of the embedded taxa in Phyllanthus over further generic segregation. Monophyletic Phyllanthus comprises an estimated 1269 species, making it one of the "giant" genera. Phyllanthus maderaspatensis is sister to all other species of Phyllanthus, and the genus appears to be of paleotropical origin. Subgenera Isocladus, Kirganelia, and Phyllanthus are polyphyletic, whereas other subgenera appear to be monophyletic. Monotypic Reverchonia is sister to P. abnormis, arborescent section Emblica to herbaceous Urinaria, free-floating aquatic P. fluitans to the weed P. caroliniensis, and the phyllocladous section Choretropsis to the delicate leafy P. claussenii. The unique branching architecture known as "phyllanthoid branching" found in most Phyllanthus taxa has been lost (and/or has been derived) repeatedly. Taxonomic divisions within Phyllantheae based on similar pollen morphology are confirmed, and related taxa share similar distributions. We recommend recognition of six clades at generic level: Flueggea s.l. (including Richeriella), Lingelsheimia, Margaritaria, Phyllanthus s.l. (including Breynia, Glochidion, Reverchonia, and Sauropus), P. diandrus, and Savia section Heterosavia.

Analysis of plastid rbcL DNA sequence data of the pantropical family Phyllanthaceae (Malpighiales) and related biovulate lineages of Euphorbiaceae sensu lato is presented. Sampling for this study includes representatives of all 10 tribes and 51 of the 60 genera attributed to Euphorbiaceae-Phyllanthoideae. Centroplacus and Putranjivaceae (Phyllanthoideae-Drypeteae) containing a paraphyletic Drypetes are excluded from Phyllanthaceae. Croizatia, previously thought to be a "basal" member of Euphorbiaceae-Oldfieldioideae (Picrodendraceae), falls within Phyllanthaceae. Phyllanthaceae with the mentioned adjustments form a monophyletic group consisting of two sister clades that mostly correspond to the distribution of tanniniferous leaf epidermal cells and inflorescence structure. With the exception of bigeneric Hymenocardieae and monotypic Bischofieae, none of the current Phyllanthoideae (Phyllanthaceae) tribal circumscriptions are supported by rbcL. Antidesma, Bischofia, Hymenocardia, Martretia, and Uapaca, all of which have previously been placed in monogeneric families, are confirmed as members of Phyllanthaceae. Savia is polyphyletic, and Cleistanthus appears paraphyletic. Paraphyly of Phyllanthus is also indicated, but this pattern lacks bootstrap support. Morphological characters are discussed and mapped for inflorescence structure, tanniniferous epidermal cells, breeding system, and fruit and embryo type. A table summarizes the main characters of six euphorbiaceous lineages.

Phylogenetic relationships and genetic divergence among congeneric species endemic to the Juan Fernandez Islands and their relatives in continental Chile were estimated using percentage of divergence of ITS of nrDNA andgenetic identity (Nei) based on allozyme variability. A total of 1151 individuals in 85 populations of 17 species was analyzed belonging to the genera Berberis (four spp.), Gunnera (four spp.), Myrceugenia (five spp.), and Sophora (four spp.). ITS regions 1 and 2 ranged between 442 and 504 bp long. The number of loci resolved differed within each genus and ranged between 5 and 11 (in Gunnera and Sophora, respectively). The new data allowed testing of previous hypotheses of relationship based on morphology and secondary products chemistry. Genetic identity values among insular congeneric species ranged between 0.936 (Gunnera) and 0.670 (Myrceugenia). ITS sequence divergence ranged from 0% (Gunnera and Sophora) to 4.2% (Myrceugenia). These values are within the ranges obtained for insular endemic species in other oceanic archipelagoes. Estimates of time of divergence of endemics from progenitors, based on isozyme data, lie between 188,500 and 2,580,000 years. The oldest island, Masatierra, is approximately 4 million years old and the youngest, Masafuera, 1-2 million years old. Genetic divergence between endemic species of Masafuera and their continental relatives is in general lower than that between endemic species of Masatierra and their putative continental ancestors. Genetic divergence is also greater between continental progenitors and derivative species in Masatierra than between endemic species pairs between Masatierra and Masafuera.

AFLP variation has been assessed within and among populations of Hypochaeris acaulis (Asteraceae), a species isolated in moist seeps and rivulets throughout its range in the southern Andes. Plants in seven papula-dons were sampled with six pairs of primer combinations. Genetic affinities were calculated by Nei-Li distance, and relationships were determined by neighbor-joining. All individuals, except two, clustered with other members of their same population. These results suggest restricted gene flow among populations, perhaps resulting from limited dispersal capability. It was estimated that a migrant is exchanged between two randomly chosen populations approximately once in eight generations, a low level of genetic exchange. A correlation of geographic and genetic distances is seen among populations, corresponding to isolation by distance. Genetic variation largely resides among populations (67.9%) rather than within (32.1%). No deep genetic divisions larger than those seen among the populations were revealed, suggesting no major biogeographic impacts, except for possible isolation of individual populations due to recent local Pleistocene glaciation. A positive correlation of genetic variation exists with population size, and a strong correlation exists with observed flowering and fruiting behavior. Pollen/ovule ratios were used to suggest that the species is facultatively autogamous, a breeding system that would be consistent with the observed pattern of genetic variation.

Nuclear internal transcribed spacer (ITS) regions and chloroplast trnL intron and trnL/trnF spacer and matK sequences were used from 86 accessions to assess relationships among 31 European and South American species of Hypochaeris plus 18 representatives of related genera of tribe Cichorieae. The ITS tree shows high resolution compared to that of the maternally inherited trnL intron, trnL/F spacer, and matK sequences. The ITS and the combined tree reveal clades that agree well with sections of the genus established previously on morphological and cytological grounds, except for H. robertia, which groups with Leontodon helveticus and L. autumnalis. Monophyly of species of Hypochaeris from South America is strongly supported by both ITS and the joint matrix of ITS, trnL, and matK data. European species lie basal to South American taxa, which suggests that species in South America evolved from a single introduction from European progenitors and not from H. robertia as suggested previously. Low levels of sequence divergence among South American taxa suggest a pattern of rapid speciation, in contrast to much greater divergence among European representatives. Different species of Leontodon form two different clades that are also supported by chromosome numbers and morphology. Both nuclear and chloroplast markers suggest that Helminthotheca, Leontodon, and Picris are closely related to each other as well as to Hypochaeris.

In recent years molecular data, especially from DNA, have provided more precise estimates of relationships among vascular plants. Different types of data have been used efficaciously at different levels of the taxonomic hierarchy from ordinal and familial classifications to genetic variation within populations. The impact on systematics has been enormous, often confirming previous hypotheses established through morphological or other data, but sometimes offering novel and surprising insights. Although it is far from clear which genes or intergenic regions will eventually be known to contain the most helpful phylogenetic information for general and special classification, it is abundantly clear that a genetic yardstick will be used routinely. The impact of molecular data on plant systematics is now having a similar import in biogeography. Sequence data, as well as DNA fingerprinting of various types, are now being employed to assess patterns of isolation and speciation, timing of changes of distributions and speciation events, routes of migration and/or dispersal, population-level divergence, and hybridization. Systematics and biogeography, therefore, are melding together more closely than ever before, because the same kinds of data can be used to address questions regarding evolutionary relationships as well as patterns of distribution in space and time. Data at the populational level are especially helpful in a multidisciplinary context for answering questions regarding infraspecific affinities and for explaining distributions resulting from recent historical and ecological factors. Examples from the genus Hypochaeris (Asteraceae) from southern South America, using DNA sequence and AFLP data, are used to illustrate these points. The genus appears to have originated in Eurasia, dispersed to South America during the past several million years, and radiated into more than 45 species that are adapted to many different ecological regimes. In den letzten Jahren haben molekulare Daten, besonders DNA-Daten, prazisere Einblicke in die Verwandtschaftsbeziehungen zwischen Hoheren Pflanzen ermoglicht. Unterschiedliche Datentypen wurden erfolgreich auf verschiedenen taxonomischen Rangstufen verwendet, von Ordnungs- und Familien-Klassifikationen bis hin zu genetischer Variation innerhalb von Populationen. Der Einfluss auf die Systematik war enorm, wobei fruhere, von morphologischen oder anderen Daten abgeleitete Hypothesen oft bestatigt wurden, manchmal jedoch neue und uberraschende Einblicke resultierten. Obwohl bei weitem noch nicht geklart ist, welche DNA-Regionen den hochsten phylogenetischen Informationsgehalt fur die Klassifikation von Gattungen und Arten enthalten, ist vollkommen klar, dass man in Zukunft einen genetischen Masstab routinemasig verwenden wird. Der Einfluss, den molekulare Daten bis jetzt auf die Pflanzensystematik ausgeubt haben, tragt nun in gleicher Weise zur Klarung biogeographischer Fragestellungen bei. So werden Sequenzdaten und verschiedene DNA Fingerprinting-Methoden dazu verwendet, Isolations- und Artbildungsmuster, Migrationsrouten, Verbreitung durch Pollen und Samen, Differenzierung von Populationen und Hybridisierung zu erforschen. Systematik und Biogeographie verschmelzen enger als je zuvor, weil dieselben Daten verwendet werden, um evolutionare Verwandtschaftsverhaltnisse und Verteilungsmuster in Raum und Zeit zu untersuchen. Daten auf dem Populationsniveau sind in einem multidisziplinaren Zusammenhang besonders hilfreich, um zwischenartliche Verwandtschaftsverhaltnisse zu untersuchen und Verteilungen zu erklaren, die aus historischen und okologischen Faktoren resultieren. Um diese Punkte zu illustrieren, verwenden wir DNA Sequenz- und AFLP-Daten anhand des Beispiels der Gattung Hypochaeris (Asteraceae) aus dem sudlichen Sudamerika. Es scheint, dass diese Gattung in Eurasien entstanden ist, innerhalb der letzten Millionen Jahre nach Sudamerika vorgedrungen ist und dort eine Radiation in mehr als 45 Arten durchgemacht hat, die an viele verschiedene okologische Nischen adaptiert sind.

Sri Lanka is a country with unique landscapes and positioning. Its land profile varies from coastal areas through lowland hills to central montane region, and the climatic zones governed by seasonal monsoons results in a significantly high biodiversity. Sri Lanka together with Western Ghats is a biodiversity hot spot among the 35 regions known worldwide. Sri Lanka harbors 3154 species of which 894 are endemics belonging to different angiosperm families. The orchid flora of the country, with 189 known species including 55 endemics is one that contributes very much for this high endemism. However 70.6% are currently listed as nationally threatened species during National Red listing in 2012. The present study was conducted to investigate the current status and occurrence of species of the family Orchidaceae within and outside the conservation areas including few unexplored/ undocumented regions in the country. Field visits were carried out mainly focusing on the flowering seasons. Fourteen different sites including Forest Reserves, Sanctuaries, Strict Nature Reserves and Wildlife Parks were taken into consideration during this study. Observations were made in the field and locations recorded, collected data were tabulated and compared with available information. The observation made during the present study would make a large contribution for updating the conservation status of orchids at national and global level red listing.

Sequences of the plastid DNA atpB/rbcL intergenic spacer and rps16 intron from 23 genera and 47 species of Rutaceae were used to resolve phylogenetic relationships in subfamily Aurantioideae. According to these, the subfamily is monophyletic, but its classical subdivision into tribes Clauseneae and Citreae is only justified if the genus Murraya s.s. (exclusive of the species segregated as Bergera, e.g., Murraya koenigii and M. siamensis) and Merrillia are transferred to Citreae s.l. This conclusion is also well supported by phytochemistry, demonstrating accumulation of carbazoles in Bergera and Clausena, and of 8-prenylated coumarins and polyoxygenated flavonoids in Murraya s.s. and Merrillia. Formation of both carbazoles, as well as 8-prenylated coumarins, and polyoxygenated flavonoids in Micromelum suggests relationships between Clauseneae s.s. and Citreae s.l. The monophyly of several larger genera in both tribes is supported by relatively high bootstrap percentages and specific chemical profiles for e.g., Clausena, Micromelum, Glycosmis and Atalantia. In contrast, molecular, chemical, and other data show that none of the subtribes recognized within Aurantioideae reflect phylogenetic relationships. Only the clades with Clausena+Bergera, Murraya s.s. +Merrillia, and Citrus+Clymenia+Eremocitrus+Fortunella+Poncirus (“true Citrus fruit trees”) are well supported by such data. Among the outgroup genera, Zanthoxylum (Rutoideae) and Toddalia (Toddalioideae) are much closer to each other than to Ruta (Rutoideae).

The genus Anemone and its close relatives (Anemoninae) encompass about 210 species. According to the most recent taxonomic survey of the Ranunculaceae (Tamura, 1995), this diversity is clearly centred in the Northern Hemisphere, but distribution is world-wide, and interesting biogeographic extensions exist into the Southern Hemisphere (Tasmania and New Zealand, South America, eastward to South Africa). Our understanding of the phylogenetic structure of Anemoninae has been greatly improved by a DNA restriction site analysis (Hoot & al., 1994; Hoot, 1995) that has demonstrated two clades, one with the chromosome base number x = 8 (including the majority of Anemone, but also several satellite genera as Knowltonia and Pulsatilla) and another with x = 7 (consisting of some Anemone groups and Hepatica). With respect to Southern Hemisphere members, Hoot & al. (1994) have shown that the Tasmanian A. crassifolia is closely related to the South African A. caffra (and Knowltonia). They placed the latter into the informal Caffra group, and the former, together with the New Zealand A. tenuicaulis (for which no DNA data were available then) into the Crassifolia group of the x = 8 clade. Tamura (1995) also accommodated A. crassifolia and A. tenuicaulis together in subg. Rivularidium sect. Crassifolia, whereas Ehrendorfer (1995) placed them in subg. Meridium. On the basis of new DNA sequence data (ITS and rbcliatpB) Schuettpelz & Hoot (2000) support the links between A. crassifolia and A. caffra + A. knowltonia within the x = 8 clade, but now correct the position of A. tenuicaulis, placing it into the x = 7 clade not far from the northeastern Asiatic A. dichotoma but without considering South American taxa. For the link South Africa-Tasmania they suggest an ancient Gondwanan distribution, for the connection Asia-New Zealand an Australasian island-hopping pattern. From our current and independent work on the intergenic cpDNA spacer rbcL/atpB in Anemoninae we would like to comment on these phylogenetic and biogeographical suggestions. Notwithstanding our still incomplete molecular analysis of Anemone (Samuel & Ehrendorfer, in prep.), available new sequences strongly support placement of the New Zealand endemic A. tenuicaulis from a position close to the Tasmanian A. crassifolia in the x = 8 clade to the x = 7 clade of Anemoninae (Fig. 1). This is in line with considerable differences in morphology (Parkin & Sledge, 1933) and palynology (Huynh, 1970a, b) between the two species. No karyological data are available for A. crassifolia, but for A. tenuicaulis Hair (1963) has reported a reliable

RAPDs were employed as genetic markers to detect interspecific hybridization between the closely related oak speciesQuercus robur andQ. petraea. Fourteen primers were used in order to check the genetic status (“pure” or hybrid) of individuals classified morphologically. Among the 147 PCR fragments obtained 11 appear to be species-specific. In the phenotypically intermediate individuals different combinations of these species-specific bands were obtained. The patterns in these putative hybrids were not additive, which may be either the result of repeated backcrossing and introgression between the two species or of heterozygosity within the parental species. The results of the RAPD study are consistent with morphological analyses and allozyme data obtained for theGot-2 locus. Thus the RAPD markers used in this study may provide a powerful genetic tool for the identification of hybrids and the discrimination between the two “pure” species.

Nucleotide sequences from the internal transcribed spacer (ITS) regions of the 18S–26S nuclear ribosomal DNA have been studied from ten species ofQuercus (representing four subgenera),Castanea sativa andFagus sylvatica, as a preliminary molecular contribution to the still poorly understood systematics and evolution ofFagaceae. The resulting matrix has been used to calculate pair-wise sequence divergence indices and to construct a maximum parsimony tree forQuercus coding indels as a fifth state. Divergence is greater forQuercus vs.Fagus than forQuercus vs.Castanea. The tree for theQuercus taxa studied reveals two clearly divergent clades. In clade I the evergreen W MediterraneanQ. suber appears in a basal position as sister to more distal deciduous taxa, i.e. the E MediterraneanQ. macrolepis and the E AsiaticQ. acutissima (all formerly united as different sections under the apparently polyphyletic subg.Cerris), andQ. rubra (a representative of the N American subg.Erythrobalanus), forming a pair withQ. acutissima. In clade II the evergreen southeastern N AmericanQ. virginiana is basal and sister to the remaining three branches, i.e. a pair of evergreen Mediterranean taxa withQ. ilex andQ. coccifera (subg.Sclerophyllodrys), the deciduous but otherwise plesiomorphic SE European/SW AsiaticQ. cerris (type species of subg.Cerris), and the related but more apomorphic European pairQ. petraea andQ. robur (subg.Quercus). These results partly conflict with current taxonomic classification but are supported by some anatomical and morphological characters. They document polyphyletic lines from evergreen to deciduous taxa and suggest Tertiary transcontinental connections within the genus.

The PCR-amplified atpB/rbcL spacer region of ten Cyrtandra species and representatives of the genera Didymocarpus, Didissandra, and Monophyllaea was sequenced and used for phylogenetic analyses. In Cyrtandra 83 variable positions were found over a length of 890bp. The data suggest that the Samoan species included in our study originated by at least two independent colonization events, while for the Hawaiian species the situation is not clear yet. With respect to generic relationships, Monophyllaea shows considerable divergence (9.9%) from the remaining taxa and thus is used as outgroup. Didymocarpus is most closely related to Cyrtandra, their genetic divergence (2.2%) being only slightly higher than the average distance within Cyrtandra (1.9%). The promoter regions for the atpB and rbcL genes, which have been described from Rubiaceae, were identified and found to be located at homologous positions. Of the two atpB promoters found in Rubiaceae only the distal one appears functional, the proximal promoter has been eroded by mutations and is disrupted in Didissandra by a 14bp insertion.

Allozyme variation at 11 loci (with 37 alleles) was studied electrophoretically in seven outbreeding, closely related diploid and tetraploid taxa, seven from sect.Leptogalium and two from sect.Leiogalium. Whereas the sections are clearly distinct by several different alleles, aggregates, species and subspecies differ only in the frequency or presence/absence of common alleles. The resulting dendrogram suggests phylogenetic relationships and is supported by other multidisciplinary evidence. Tetraploids have originated independently in several groups, and there is evidence for tetrasomic inheritance and thus for autopolyploidy in spite of normal meiotic bivalent pairing and partly suspected hybrid origin. Tetraploids differ from related diploids only little in number of alleles and expected heterozygosity within populations, but clearly exhibit higher numbers of genotypes. This often corresponds to their greater morphological variability, increased adaptive flexibility, and better colonizing capacity compared to related diploids.

Premise of the study: PCR amplification of the matK barcoding region is often difficult when dealing with multiple angiosperm families. We developed a primer cocktail to amplify this region efficiently across angiosperm diversity. Methods and Results: We developed 14 matK primers (seven forward, seven reverse) for multiplex PCR, using sequences available in GenBank for 178 taxa belonging to 123 genera in 41 families and 18 orders. Universality of these new multiplexed primers was tested with 53 specimens from 44 representative angiosperm families in 23 different orders. Our primers showed high PCR amplification and sequencing success. Conclusions: These results show that our newly developed primers are highly effective for multiplex PCR and can be employed in future barcode projects involving taxonomically diverse samples across angiosperms. Using multiplex primers for barcoding will reduce the cost and time needed for PCR amplification.

Phylogenetic analyses of Meliaceae, including representatives of all four currently recognized subfamilies and all but two tribes (32 genera and 35 species, respectively), were carried out using DNA sequence data from three regions: plastid genes rbcL, matK (partial), and nuclear 26S rDNA (partial). Individual and combined phylogenetic analyses were performed for the rbcL, matK, and 26S rDNA data sets. Although the percentage of informative characters is highest in the segment of matK sequenced, rbcL provides the greatest number of informative characters of the three regions, resulting in the best resolved trees. Results of parsimony analyses support the recognition of only two subfamilies (Melioideae and Swietenioideae), which are sister groups. Melieae are the only tribe recognized previously that are strongly supported as monophyletic. The members of the two small monogeneric subfamilies, Quivisianthe and Capuronianthus, fall within Melioideae and Swietenioideae, respectively, supporting their taxonomic inclusion in these groups. Furthermore, the data indicate a close relationship between Aglaieae and Guareeae and a possible monophyletic origin of Cedreleae of Swietenioideae. For Trichilieae (Melioideae) and Swietenieae (Swietenioideae) lack of monophyly is indicated.

Molecular phylogenetic studies of seven plastid DNA regions were used to resolve circumscriptions at generic and infrageneric levels in subfamily Tillandsioideae of Bromeliaceae. One hundred and ten tillandsioid samples were analyzed, encompassing 10 genera, 104 species, and two cultivars. Two species of Bromelioideae, eight species of the polymorphic Pitcairnioideae, and two species of Rapateaceae were selected as outgroups. Parsimony analysis was based on sequence variation of five noncoding (partial 5' and 3' trnK intron, rps16 intron, trnL intron, trnL-trnF intergenic spacer, atpB-rbcL intergenic spacer) and two coding plastid regions (rbcL and matK). Phylogenetic analyses of individual regions produced congruent, but mostly weakly supported or unresolved clades. Results of the combined data set, however, clearly show that subfamily Tillandsioideae is monophyletic. The earliest divergence separates a lineage comprised of Glomeropitcairnia and Catopsis from the "core" tillandsioids. In their present circumscriptions, genera Vriesea and Tillandsia, and their subgenera or sections, as well as Guzmania and Mezobromelia, are poly- and/or paraphyletic. Genera Alcantarea, Werauhia, Racinaea, and Viridantha appear monophyletic, but separation of these from Vriesea and Tillandsia makes the remainder paraphyletic. Nevertheless, Tillandsioideae separates into four main clades, which are proposed as tribes, viz., Catopsideae, Glomeropitcairnieae, Vrieseeae, and Tillandsieae.

We performed maximum parsimony and Bayesian analyses (nuclear ITS rDNA, plastid rps16 intron) to estimate phylogenetic relationships within Aglaia (over 100 species in Southeast Asia, the Pacific, and Australia) and its relations among Aglaieae (Meliaceae). Based on 67 accessions of Aglaieae, three taxa of Guareae, and two taxa of Melieae (outgroup), this study provides the first assessment of the current circumscription of Aglaieae, Aglaia, and its sections and to a more limited extent of species concepts in Aglaia. DNA data are compared to recently collected data on chemical profiles. Our analyses indicate (1) the monophyly of Aglaieae; (2) the polyphyly of Aphanamixis; (3) the paraphyly of Aglaia; (4) the existence of at least three entities with respect to Aglaia: (a) the core group of Aglaia section Amoora (dehiscent fruits) with close relationships to Lansium and Reinwardtiodendron, (b) a group comprising morphological intermediates between the two sections, and (c) the core group of Aglaia section Aglaia (indehiscent fruits). Macro- and micromolecular data indicate that complex species are more heterogeneous, i.e., probably containing more than one taxon each, than taxonomically isolated species. A third section in Aglaia is recognized to accommodate A. lawii, A. teysmanniana, and A. beccarii.

The plastid matK gene, trnL/F spacer, and nuclear rDNA ITS were sequenced for 36 species of Leontodon and 29 taxa of related genera of tribe Lactuceae. Phylogenetic relationships inferred from the independent and combined data are largely congruent and reveal that Leontodon sensu lato (s.l.) as presently defined is diphyletic: L. subgenus Leontodon forms a clade with Helminthotheca, Picris and Hypochaeris as sister genera, whereas L. subgenus Oporinia appears as a separate clade with strong bootstrap support and is thus better treated as a separate genus. Previous sectional classifications of Leontodon s.l. are considered in the light of DNA and additional morphological and karyological data. Support is presented for a core group of Hypochaeridinae sensu stricto (s.s.) with the two clades of Leontodon s.l., Helminthotheca, Picris, and Hypochaeris, whereas Urospermum, Hyoseris, Aposeris, and Rhagadiolus appear to be positioned more distantly.

Macaranga and Mallotus (Euphorbiaceae s.s.) are two closely related, large paleo(sub)tropical genera. To investigate the phylogenetic relationships between and within them and to determine the position of related genera belonging to the subtribe Rottlerinae, we sequenced one plastid (trnL-F) and three nuclear (ITS, ncpGS, phyC) markers for species representative of these genera. The analyses demonstrated the monophyly of Macaranga and the paraphyly of Mallotus and revealed three highly supported main clades. The genera Cordemoya and Deuteromallotus and the Mallotus sections Hancea and Oliganthae form a basal Cordemoya s.l. clade. The two other clades, the Macaranga clade and the Mallotus s.s. clade (the latter with Coccoceras, Neotrewia, Octospermum, and Trewia), are sister groups. In the Macaranga clade, two basal lineages (comprising mostly sect. Pseudorottlera) and a crown group with three geographically homogenous main clades were identified. The phylogeny of the Mallotus s.s. clade is less clear because of internal conflict in all four data sets. Many of the sections and informal infrageneric groups of Macaranga and Mallotus do not appear to be monophyletic. In both the Macaranga and Mallotus s.s. clades, the African and/or Madagascan taxa are nested in Asian clades, suggesting migrations or dispersals from Asia to Africa and Madagascar.

International audience; We aimed to clarify phylogenetic relationships within the pantropical genus Diospyros (Ebenaceae sensulato), and ascertain biogeographical patterns in the New Caledonian endemic species. We used DNA sequences from eight plastid regions (rbcL, atpB, matK, ndhF, trnK intron, trnL intron, trnL-trnF spacer, and trnS-trnG spacer) and included 149 accessions representing 119 Diospyros species in our analysis. Results from this study confirmed the monophyly of Diospyros with good support and provided a clearer picture of the relationships within the genus than in previous studies. Evidence from phylogenetic analyses suggests that Diospyros colonized New Caledonia multiple times. The four lineages of Diospyros in New Caledonia also differ in their degree of diversification. The molecular data indicate that one lineage is paleoendemic and derived from an ancient Australian species. The other three lineages are more closely related to several Southeast Asian species; two of them are neoendemics, and one has radiated rapidly and recently.

Five species ofAnnona and one species fromArtabotrys, Cananga, Polyalthia, andRollinia were investigated in regard to 11 different allozyme loci. Preliminary studies on small population samples ofAnnona suggest genetic uniformity in three species and variability within and between populations in two other species. The allotetraploid origin ofA. glabra is clearly shown by its hybrid enzyme bands. The genetic distance between fiveAnnona species partly corresponds with their morphological relationships; onlyA. muricata appears more separated than is suggested by morphology. A comparison of the five genera demonstrates close relationship betweenAnnona andRollinia. Two enzyme loci are identical within all taxa investigated and possibly may serve as a genetic marker for the family.

Five polymorphic enzyme genes (Est-1, Est-5, Got-2, Pgi-2 and 6-Pgdh-1) were studied in Lower Austrian populations of the herbaceous, allogamous polyploid complex Galium pusillum agg. Allele frequencies in the relic G. austriacum-2x document a high amount of genetic differentiation between the isolated, rather uniform and stenoecious populations which are separable into an older mountain and a more recent foothill series. Genetic divergence from G. austriacum-2x is small in G. austriacum-4x and only somewhat greater in G. pumilum-8x. Allele frequencies in the 4x (and 8x) suggest tetrasomic inheritance and autopolyploid behaviour in spite of nearly exclusive bivalent formation. The amount of genie variation (number of different alleles and average heterozygosity) appears uniform in diploids and polyploids. In contrast, the polyploids exhibit much increased genotypic variation as compared to the diploids. This can be linked to their more continuous, variable, euryoecious and expansive populations.

The genus Cephalanthera is an excellent plant group for karyotype evolution studies because it exhibits a dysploid series and bimodal karyotypes. With the aim of understanding their chromosomal and phylogenetic relationships, rRNA genes and the Arabidopsis-type telomeric sequence were mapped by fluorescence in-situ hybridization (FISH), and the rDNA intergenic spacer (ITS) was sequenced for the first time in three European species: C. longifolia (2n = 4x = 32), C. damasonium (2n = 4x = 36) and C. rubra (2n = 4x = 44). One 45S and three 5S rDNA sites are observed in C. longifolia, one 45S and two 5S sites in C. damasonium, and two 45S and one 5S site in C. rubra. Telomeric signals were observed at every chromosome end in all three species and C. damasonium also displays interstitial signals on three chromosome pairs. In agreement with chromosome data, molecular analyses support C. longifolia and C. damasonium as closely related taxa, while C. rubra stands apart. Possible pathways of karyotype evolution are discussed in reference to a previous hypothesis. The results indicate that complex chromosomal rearrangements, possibly involving Robertsonian fusions and fissions, loss of telomeric repeats, gain or loss of rDNA sites and other heterochromatic sequences and inversions, may have contributed to generating the present-day karyotypes. Fil: Moscone, Eduardo Alberto. Universidad de Viena; Austria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Samuel, Rosabelle. Universidad de Viena; Austria Fil: Schwarzacher, Trude. University of Leicester; Reino Unido Fil: Schweizer, Dieter. Universidad de Viena; Austria Fil: Pedrosa-Harand, Andrea. Universidad de Viena; Austria

This study aims to analyze the diversity of Ty1-copia retrotransposons in 18 taxa of Hypochaeris, including two Old World species H. maculata (2n=2x=10) and H. angustifolia (2n=2x=8), and representatives of the South American species (16 accessions of 15 species; all 2n=2x=8). Analysis of 380 PCR-amplified sequences, corresponding to a conserved domain of the subset of Ty1-copia reverse transcriptase (rt) gene amplifiable with degenerate standard primers, showed high levels of intra- and interspecific heterogeneity. Nucleotide diversity (Pi) of the copia fragments was high in all species and varied from 0.229 (H. angustifolia) to 0.412 (H. chillensis). Higher sequence heterogeneity correlates positively with larger genome size among analyzed species. Phylogenetic analyses of amplified fragments revealed different patterns of intraspecific heterogeneity within species, with most sequences forming one well-supported main clade while a few sequences fall into small clades or are left ungrouped. The combined analysis of all sequences revealed the presence of three main clades and showed that highly diverged species contain closely related Tyl-copia group retrotransposons. One of the main clades includes rt sequences of all South American species and three sequences of their putative ancestor, H. angustifolia, but no sequence of the Old World H. maculata. FISH with copia retrotransposons in four Hypochaeris species, including H. maculata and H. angustifolia and New World H. apargioides and H. spathulata, revealed differences in the chromosomal distribution between the two groups. In Old World species copia retroelements are distributed over the whole length of the chromosomes, excluding rDNA sites and some centromeres. In the South American species the two largest chromosome pairs are enriched in copia, while most of the long arms of the two small pairs of chromosomes are devoid of these elements. The patterns of heterogeneity and chromosomal distribution of Ty1-copia retrotransposons in Hypochaeris are discussed in the context of the origin, genome evolution and organization of the South American species.

Phylogenetic relationships of the pantropical family Ebenaceae s.l. were investigated using plastid DNA sequence data from six regions: atpB, matK, ndhF, trnK intron, trnL intron, and trnL-trnF spacer. Sampling included representatives of all currently recognized genera of Ebenaceae, Diospyros, Euclea, and Lissocarpa, and nearly all taxa that were previously recognized at the generic level, e.g., Cargillia, Gunisanthus, Maba, Macreightia, Royena, and Tetraclis. Our results strongly support monophyly of Ebenaceae s.l. and demonstrate that the previous infrafamilar classifications of the family do not circumscribe monophyletic groups. A new infrafamilial classification based on a phylogenetic approach is proposed here and consists of two subfamilies, Lissocarpoideae and Ebenoideae, and four genera, Lissocarpa, Euclea, Royena, and Diospyros. Relationships and potential synapomorphic characters are discussed and summarized. This study supports a western Gondwanan origin of family and indicates that both vicariant and long-distance dispersal events played an important role in attaining current distributions.

Phyllanthaceae are a pantropical family of c. 2000 species for which circumscription is believed to be coincident with subfamily Phyllanthoideae of Euphorbiaceae sensu lato (Malpighiales) excluding Putranjivaceae. A phylogenetic study of the family using DNA sequence data has delivered largely congruent results from the plastid atpB, matK, ndhF, rbcL, and the nuclear PHYC. Our analyses include sampling from 54 of 59 genera, representing all tribes and subtribes of Phyllanthoideae. The family falls into two major clades characterized by inflorescence and leaf anatomical features. Several traditional taxonomic groupings were retrieved with minor modifications, but most clades recovered are considerably different from previous non-molecular based ideas of relationships. The enigmatic genus Dicoelia and the geographically disjunct genus Lingelsheimia are shown to be embedded in Phyllanthaceae. The taxonomic status of Leptopus diplospermus (=Chorisandrachne) and the debated placement of Andrachne ovalis have been clarified, and Protomegabaria and Richeriella are newly placed. Paraphyly of Cleistanthus and Phyllanthus is confirmed, having three and four other genera embedded, respectively. Petalodiscus is also paraphyletic, including all other Malagassian Wielandieae.

Background : Radiation in some plant groups has occurred on islands and due to the characteristic rapid pace of phenotypic evolution, standard molecular markers often provide insufficient variation for phylogenetic reconstruction. To resolve relationships within a clade of 21 closely related New Caledonian Diospyros species and evaluate species boundaries we analysed genome-wide DNA variation via amplified fragment length polymorphisms (AFLP). Results : A neighbour-joining (NJ) dendrogram based on Dice distances shows all species except D. minimifolia,D. parviflora and D. vieillardii to form unique clusters of genetically similar accessions. However, there was little variation between these species clusters, resulting in unresolved species relationships and a star-like general NJ topology. Correspondingly, analyses of molecular variance showed more variation within species than between them. A Bayesian analysis with BEAST produced a similar result. Another Bayesian method, this time a clustering method, STRUCTURE, demonstrated the presence of two groups, highly congruent with those observed in a principal coordinate analysis (PCO). Molecular divergence between the two groups is low and does not correspond to any hypothesised taxonomic, ecological or geographical patterns. Conclusions : We hypothesise that such a pattern could have been produced by rapid and complex evolution involving a widespread progenitor for which an initial split into two groups was followed by subsequent fragmentation into many diverging populations, which was followed by range expansion of then divergent entities. Overall, this process resulted in an opportunistic pattern of phenotypic diversification. The time since divergence was probably insufficient for some species to become genetically well-differentiated, resulting in progenitor/derivative relationships being exhibited in a few cases. In other cases, our analyses may have revealed evidence for the existence of cryptic species, for which more study of morphology and ecology are now required.