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Polyploidy plays a significant role in the evolution and diversification of flowering plants. In several polyploid complexes, high morphological variability and plasticity coupled with cytogenetic diversity make it difficult to disentangle their evolutionary history. The main goal of this study was to gain insights into the role of whole genome duplications as one of the factors shaping the evolution of flowering plants. Linum suffruticosum s.l. has been described as a polyploid complex, with high morphological variability, but nothing is known about current cytogeographical patterns. We investigated cytotype diversity and distribution patterns in 151 populations covering most of the distribution range, in the Iberian Peninsula, south-eastern France, north-western Italy and Morocco, using flow cytometric analyses complemented with chromosome counts. A high cytogenetic diversity was found with five major cytotypes being detected (diploids, tetraploids, hexaploids, octoploids and decaploids) and with new ploidy levels being reported for the first time. The different ploidies were distributed parapatrically, with geographical structure and several contact zones. Most of the populations comprised one cytotype, but a few mixed-ploidy populations were observed. Our results suggest that whole genome duplications are one of the key mechanisms, alone or together with hybridization, governing the diversification of L. suffruticosum s.l. Genome size and/or chromosome counts might be useful tools for identifying specimens of L. suffruticosum s.l. Also, geographical overlap and high cytogenetic diversity suggest multiple origins of the polyploids. The diversity observed here has been mostly neglected to date and should be accounted when studying the biosystematics of this complex.

Hybridization associated with polyploidization and apomixis is a frequent mechanism of speciation.Sorbusis a genus with ongoing hybridization resulting in a polyploid complex with different parental lineage.Triparensis the smallest hybridogenous subgenus ofSorbusso far known to comprise only two taxa,S. intermediaandS. × liljeforsiithat combine the genomes of three taxa (S. ariaagg.,S. aucupariaandS. torminalis). To elucidate the origins ofS. dacica,S. paxianaandS. tauricola, three new trigenomic candidates formerly believed to be of biparental origin with eitherS. ariaagg. × S. aucupariaorS. ariaagg. × S. torminalislineage we combined data from HPLC and chloroplast DNA analysing additional 33 related taxa as well. We concluded that the ‘torminalis-type’ flavonoid profile and the ‘aucuparia-type’ plastid indicate the participation of bothS. torminalisandS. aucupariaresulting in the formation ofS. dacica,S. paxianaandS. tauricola.Sorbus ariaagg. as the third ancestor and as a necessary link to meet genes ofS. torminalisandS. aucupariain one genome is obvious from morphological features (densely tomentose undersides of leaves). The tetraploid cytotypes and obligate pseudogamy ofS. dacicaandS. paxianawere determined by flow cytometry and are published here for the first time. The most probable evolutionary scenario forTriparensspecies is: 1. a diploid sexualS. aucupariaas pollen acceptor hybridized with a tetraploid apomictic taxon from theS. ariaagg. producing a triploid apomictic taxon with ‘aucuparia-type’ plastid inherited maternally; 2. during a second crossing event this subgenusSorariahybrid as maternal progenitor hybridized with the sexual diploidS. torminalis(providing gene(s) of apigenin O-glucuronide synthesis) forming a tetraploidTriparenshybrid with ‘aucuparia-type’ plastid and ‘torminalis-type’ flavonoids.

International audience; The economically important Allium ampeloprasum L. represents a polyploid complex, comprising hexa- and octoploid Great Headed Garlic horticultural cultivars (6x-8x GHG) and several traditional varieties of the tetraploid (4x) leeks (Leek, Bulbous leek, Kurrat and Pearl onion). Its wild representatives were indicated as rare in the Mediterranean region. This study aims to explore the diversity and origin of polyploidy in this complex, including its wild relatives A. baeticum Bossier and A. guttatum Steven with particular focus on the poorly investigated North-African region. Natural populations were sampled in Algeria in various bioclimatic conditions, then subjected to karyological and molecular phylogenetic analyses based on nuclear rDNA ITS region and chloroplast trnL-trnF and trnD-trnT intergenic spacers. Comparative analyses included available Genbank accession sequences representing old-world relatives. Chromosome count surveys revealed an unexpected higher occurrence of diploid (2n = 16) than tetraploid (2n = 32) cytotypes. The phylogenetic analyses first allowed positioning the Algerian material within the A. ampeloprasum complex. Interestingly, all the Algerian diploid and tetraploid populations from A. ampeloprasum and A. baeticum form a distinct monophyletic group. The results provide novel and robust evidence demonstrating that the North African diploid A. ampeloprasum genetic pool widely contributed as a source of progenitors not only for the A. ampeloprasum and A. baeticum Algerian tetraploids, but also in the formation of the GHG and Leek cultivated allopolyploids. Therefore, the North African populations emerge as an important reservoir of new wild genetic resources of great interest for tracing the origin of crop domestication and for breeding programs of cultivated varieties.

This study is the first report of a genetic stability analysis of a polyploid complex maintained in vitro for a long-time. Twenty-two accessions of Lippia alba, a medicinal species of economic importance, had been maintained under in vitro culture conditions for 7 years through sprouting of axillary buds. Four clones of each accession were analyzed, being three plants from in vitro bank and one cultivated in the field. We investigated the genetic stability of diploid, aneuploid, triploid, tetraploid, and hexaploid accessions. The investigation was carried out using flow cytometry, inter simple sequence repeat (ISSR) and simple sequence repeat (SSR) markers. No significant variation in nuclear DNA content was observed between the in vitro conserved plants and their respective field plant. Out of 23 ISSR primers screened, 8 primers were found to produce clear reproducible bands resulting in a total of 5456 bands. 86.36% of the analyzed plantlets (19 accessions) showed at least one polymorphic band. The polymorphic rate ranged from 1.61 to 33.87%. The SSR markers were used to confirm the absence or low occurrence of variation in accessions that showed no polymorphism or polymorphism for only one ISSR primer. The genetic instability detected in our study at the molecular level may be attributed to the natural instability of L. alba genome combined with the long-time in vitro maintenance.

[EN] Centaurea aspera polyploid complex represents a comprehensive model. The aim of this short communication was to study the mating system of the three main species. The results showed that allotetraploid C. seridis was self-compatible (SC), while autotetraploid C. gentilii was self-incompatible (SI) as the diploid parental C. aspera (SI)., This work was supported by Generalitat Valenciana through AICO/2019/227 project.

Polyploidy is widely recognized as a major evolutionary force in plants and has been reported in the genus Lippia (Verbenaceae). Lippia alba, the most studied species, has been documented as a polyploid complex involving at least four ploidal levels. L. alba presents remarkable chemical and genetic variation and represents a model for understanding genome organization. Although the economic and medicinal importance of the species has been widely described, no established polyploid induction protocol has been reported so far. Here, we describe the production of synthetic polyploid plants of L. alba using colchicine. The ploidal levels were estimated by flow cytometry and chromosome counting. In addition, FISH and molecular markers approaches were used to confirm the stability of the synthetic polyploids. The major component of the essential oils was estimated by GCMS to compare with the natural individuals. Tetraploids and triploids were produced providing new opportunities for investigating medicinal, pharmacological, and economic applications as well as addressing intrinsic questions involved in the polyploidization process in tropical plants.

[EN] How polyploids become established is a long-debated question, especially for autopolyploids that seem to have no evolutionary advantage over their progenitors. The Centaurea aspera polyploid complex includes diploid C. aspera and two related tetraploids C. seridis and C. gentilii. Our purpose was to study the mating system among these three taxa and to analyze its influence on polyploid establishment. The distribution and ploidy level of the Moroccan populations, and forced intra- and inter-specific crosses were assessed. Allotetraploid C. seridis produced more cypselae per capitulum in the intra-specific crosses. It is a bigger plant and autogamous, and previous studies indicated that selfing forces the asymmetric formation of sterile hybrids. All these characteristics help C. seridis to avoid the minority-cytotype-exclusion effect and become established. Inter-specific hybridization was possible between C. aspera and C. gentilii, and with the symmetric formation of hybrids. However, 49% of the hybrid cypselae were empty, which probably reveals postzygotic barriers. Autotetraploid C. gentilii produced the same number of cypselae per capitulum as those of the diploid parental, has an indistinguishable field phenotype, is allogamous, and symmetrically produces hybrids. Therefore, C. gentilii does not seem to have the same competitive advantages as those of C. seridis., This research was funded by the Conselleria d'Educacio, Cultura i Esport (Generalitat Valenciana) with project AICO/2019/227.

International audience; Prospero seisumsianum (Ruksans & Zetterl.) Yıldırım, a species recently described in southeastern Turkey, was recorded for the first time in the flora of Iraq based on samples collected from the Amadya and Duhok areas (northern Iraq). Our contribution here will be to find out more about its description, cytology, and chorology. The specimen collected from the Mesopotamian dry plain differs slightly from those collected from the mountainous Zagros forest area, but converges after a cultivation period. Both are treated here as P. seisumsianum and have the same genome size (2C = 8.77 ± 0.24 pg) corresponding to a diploid level. Three chromosome counts gave the same 2n = 2x = 14 karyotype. We hypothesize here that all the historical mentions of P. ?autumnale? in Iraq actually correspond to P. seisumsianum. Comparative morphological description, genome size, ecological niche, and biogeography of the related taxa, and a revised key for Prospero taxa from the Irano-Anatolian enlarged to its Mediterranean border are given in the present study.

Some tropical Bignoniaceae form sporophytic apomictic polyploid complexes are similar to better studied temperate plants. Handroanthus ochraceus is a widely distributed Neotropical savanna tree with both monoembryonic/self-sterile, and polyembryonic/apomictic and self-fertile populations, but lacking chromosome number and morphological comparative studies. We tested if monoembryonic/non-apomictic and polyembryonic/apomictic populations differed in ploidy and morphological features, as a basis to understand evolution and biogeography of these plants. Chromosome number and embryo number per seed were investigated, and uni- and multivariate analyses of flower and leaf morphology were done for five populations of H. ochraceus. We found two pure monoembryonic diploid (2n = 40), and one pure polyembryonic (62–94% of polyembryonic seeds) tetraploid population (2n = 80). One of the diploid populations presented only one individual with 3.2% polyembryonic seeds and was considered a non-apomictic population. Another population showed predominantly polyembryonic (27–66% of polyembryonic seeds) tetraploid individuals, but one diploid individual with 2% of polyembryonic seeds, and was considered a mixed apomictic and non-apomictic population. Morphological analyses confirmed breeding system clusters, and that stigma width, as well as pollen grain area, was consistently larger in polyembryonic populations. Polyploid plants showed larger cells, as well as larger organs and other distinctive features, which will be useful to identify apomictic populations and to future taxonomic discussions. The species can be considered an agamic complex with apomixis associated with neopolyploidy. This trend is also found in other tropical sporophytic apomictics, contrasting with the usual reports linking diploidy or paleopolyploidy to this kind of apomictics.

Data on differentiation of the polyploid complex of Suaeda corniculata (C.A. Mey.) Bunge in East Siberia based on variability of morphological characteristics, karyological analysis, and genetic polymorphism in inter simple sequence repeat (ISSR) markers were given for the first time. It was established that the samples studied belonged to three cytotypes: diploids (2n = 2x = 18), tetraploids (2n = 4x = 36) and hexaploids (2n = 6x = 54). The analysis of variability of morphological characteristics by the method of principal coordinates showed division of the samples into three separate groups. On the basis of morphological and molecular-genetic methods, a genetically differentiated diploid population was revealed in Yakutia.

PREMISE OF THE STUDY Unrecognized variation in ploidy level can lead to an underestimation of species richness and a misleading delineation of geographic range. Caltha leptosepala (Ranunculaceae) comprises a complex of hexaploids (6x), rare nonaploids (9x), and dodecaploids (12x), all with unknown distributions. We delineate the geographic distribution and contact zones of the cytotypes, investigate morphologies of cytotypes and subspecies, and discuss the biogeography and evolutionary history of the polyploid complex. METHODS Using cytologically determined specimens as reference, propidium iodide flow cytometry was performed on silica-dried samples and herbarium specimens from across the range of C. leptosepala s.l. Genome size estimates from flow cytometry were used to infer cytotypes. A key morphological character, leaf length-to-width ratio, was measured to evaluate whether these dimensions are informative for taxon and/or cytotype delimitation. KEY RESULTS Dodecaploids were more northerly in distribution than hexaploids, and a single midlatitude population in the Northern Rockies yielded nonaploids. Genome size estimates were significantly different between all cytotypes and between hexaploid subspecies. Leaf length-to-width ratios were significantly different between subspecies and some cytotypes. CONCLUSIONS Caltha leptosepala presents clear patterns of cytotype distribution at the large scale. Marked differences in morphology, range, and genome size were detected between the hexaploid subspecies, C. leptosepala subsp. howellii in the Cascade-Sierra axis and C. leptosepala subsp. leptosepala in the Rockies. Sympatry between cytotypes in the Cascades and a parapatric distribution in the Northern Rockies suggest unique origins and separate lineages in the respective contact zones.

The family Sphaeriidae is a group of cosmopolitan freshwater clams that inhabit temporary and permanent fluvial and lacustrine environments around the world. In Chile, Sphaeriidae is represented by 11 species belonging to the genera Musculium, Pisidium and Sphaerium. In this study, the nuclear DNA content (or 2C-value) of Musculium argentinum (d’Orbigny, 1835) and Pisidium llanquihuense Ituarte, 1999 was estimated for the first time. Musculium argentinum showed a 2C-value of 3.7 ± 0.38 pg, whereas P. llanquihuense showed a 2C-value of 3.57 ± 0.36 pg. These 2C-values are within the range previously reported for Sphaeriidae (2.35–5.7 pg), which includes diploids and polyploids, amounting to 13 of the species examined around the world. Of the cytological data available for the family, the nuclear DNA content can have a unifying role in understanding the magnitude of the chromosome polymorphisms within this polyploid complex.

Polyploidy (the state of having more than two genome copies) is widely distributed in flowering plants and can vary within species, with polyploid races often associated with broad ecological tolerances. Polyploidy may influence within-species variation in seed development, germination and establishment. We hypothesized that interactions between polyploidy and the seed developmental environment would affect subsequent dormancy, germination and early growth traits, particularly in stressful environments. Using seeds developed in a common garden under ambient and warmed conditions, we conducted germination trials under drought and temperature stress, and monitored the subsequent growth of seedlings. The study species, Themeda triandra, is a widespread, keystone, Australian native grass and a known polyploid complex. Tetraploid plants produced heavier, more viable seeds than diploids. Tetraploids were significantly more dormant than diploids, regardless of seed developmental environment. Non-dormant tetraploids were more sensitive to germination stress compared to non-dormant diploids. Finally, tetraploid seedlings were larger and grew faster than diploids, usually when maternal plants were exposed to developmental temperatures atypical to the source environment. Seed and seedling traits suggest tetraploids are generally better adapted to stressful environments than diploids. Because tetraploid seeds of T. triandra are more dormant they are less likely to germinate under stress, and when they do germinate, seedling growth is rapid and independent of seed developmental environment. These novel results demonstrate that polyploidy, sometimes in interaction with developmental environment and possibly also asexuality, can have within-species variation in seed and seedling traits that increase fitness in stressful environments.

Premise of the study Polyploidy is widely recognized as a mechanism of diversification. Contributions of polyploidy to specific pre- and postzygotic barriers-and classifications of polyploid speciation as "ecological" vs. "non-ecological"-are more contentious. Evaluation of these issues requires comprehensive studies that test ecological characteristics of cytotypes as well as the coincidence of genetic structure with cytotype distributions. Methods We investigated a classical example of autopolyploid speciation, Larrea tridentata, at multiple areas of cytotype co-occurrence. Habitat and phenological differences were compared between diploid, tetraploid, and hexaploid populations on the basis of edaphic, community composition, and flowering time surveys. Frequency of hybridization between diploids and tetraploids was investigated using a diploid-specific chloroplast DNA (cpDNA) marker; genetic structure for all cytotypes was assessed using amplified fragment length polymorphisms (AFLPs). Key results Across contact zones, we found cytotypes in habitats distinguished by soil and vegetation. We observed modest differences in timing and production of flowers, indicating a degree of assortative mating that was asymmetric between cytotypes. Nonetheless, cpDNA analyses in diploid-tetraploid contact zones suggested that ∼5% of tetraploid plants had hybrid origins involving unilateral sexual polyploidization. Genetic structure of AFLPs largely coincided with cytotype distributions in diploid-tetraploid contact zones. In contrast, there was little structure in areas of contact between tetraploids and hexaploids, suggesting intercytotype gene flow or recurrent hexaploid formation. Conclusions Diploid, tetraploid, and hexaploid cytotypes of L. tridentata are segregated by environmental distributions and flowering phenology in contact zones, with diploid and tetraploid populations having corresponding differences in genetic structure.

Pollen quality was evaluated in Pilosella plants sourced from the field and representing various cytotypes (diploid to octoploid), reproduction modes (sexuality, facultative apomixis and seed sterility or semisterility) and status of origin (basic species, hybridogenous intermediate species and recent hybrids). Two methods of non-vital pollen staining were compared, providing a similar pattern of variation in pollen stainability and pollen size. A complex influence of ploidy level, reproduction mode and plant origin on pollen quality was found. Sexual biotypes had high and equable pollen stainability whereas apomictic and (semi)sterile plants were more variable in this trait. Nevertheless, the sexual, apomictic and (semi)sterile plants did not significantly differ in pollen stainability, while the impacts of both ploidy level and plant origin were significant. Apomictic triploids had low pollen stainability and heterogeneously sized pollen, most likely resulting from disturbed meiosis. The other biotypes, including higher odd-ploid cytotypes, displayed various patterns of pollen quality partially depending on the hybridogenous origin. Whereas high pollen quality was detected in most of the apomictic hexaploids and heptaploids, including recent hybrids, serious pollen dysfunction was found in most octoploids. Seed (semi)sterility was not strongly associated with reduced pollen quality. Either blocked or unstable pollen production was occasionally recorded, predominantly among recent hybrids. Despite autonomous apomixis independent of pollen, most apomictic biotypes displayed fairly high pollen stainability and pollen size homogeneity, implying sufficient production of viable reduced pollen. Most representatives of this agamic polyploid complex, including facultative apomicts, might efficiently mate as both male and female parents in natural populations.

Made available in DSpace on 2018-11-26T16:33:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Neopolyploidy has been associated with gametophytic apomixis and breakdown of gametophytic self-incompatibility. Nevertheless, Bignoniaceae presents agamic polyploid complexes with neopolyploidy associated to sporophytic apomixis. Apomictic populations are commonly polyploid, polyembryonic and self-fertile, while diploids are mostly late-acting self-incompatible (LSI) and monoembryonic. Contrastingly, Handroanthus serratifolius shows hexaploid monoembryonic and polyembryonic populations, although breeding system has been studied only for monoembryonic individuals, which are LSI. Our aim here was to investigate breeding system and early embryology in polyembryonic individuals of H. serratifolius to define if they form an agamic polyploid complex. Experimental pollinations and histological analyzes of ovules and young seeds were carried out. Megasporogenesis and megagametogenesis occurred as in other sexual species of Bignoniaceae. The polyembryonic individuals were self-fertile and double fertilization was observed both after self and cross-pollinated pistils. Adventitious embryos originated from the hypostasis and integument of the ovule, indicating sporophytic apomixis. Adventitious embryo precursor cells occurred in all pistils, including unpollinated ones. But unpollinated pistils aborted possibly due to absence of endosperm, and pollination was required for fruit-set (pseudogamy). It is possible that the self-fertility in polyembryonic individuals ensues as the initial endosperm of self-fertilized ovules supply early adventitious embryos development, and these embryos would later prevent the abortion of selfed pistils. The sporophytic apomixis in polyembryonic populations and the occurrence of sexual monoembryonic populations of H. serratifolius allows us to consider the species part of an agamic polyploid complex. But in contrast with other Handroanthus agamic complexes, both apomictic and sexual LSI plants were hexaploid. Univ Fed Uberlandia, Inst Biol, Campus Umuarama,Rua Ceara S-N,Bloco 2D, BR-38400902 Uberlandia, MG, Brazil Univ Estadual Paulista, Dept Zool & Bot, Campus Sao Jose do Rio Preto, BR-15054000 Sao Paulo, Brazil Univ Estadual Paulista, Dept Zool & Bot, Campus Sao Jose do Rio Preto, BR-15054000 Sao Paulo, Brazil CAPES: CAPES/PNPD 23038008068/2010-95

Camellia reticulata is a well-known woody ornamental species endemic to Southwest China. It represents a polyploid complex with diploids, allotetraploids, and allohexaploids. The parentage of the allotetraploids and allohexaploids has been reported by genomic in situ hybridization, but the maternal parents still remain unknown. In this study, sequences of the chloroplast rpl16 intron of 105 cultivars of C. reticulata and 7 congeneric species were used to infer the maternal origin of the allopolyploids. The results showed that (1) the allotetraploids were derived from C. pitardii as the maternal parental species and the diploid C. reticulata as the paternal parental species; (2) the allohexaploid C. reticulata was derived from the allotetraploid C. reticulata as the maternal parent and C. saluenensis as the paternal parent; and (3) the C. reticulata cultivars were derived from hexaploid C. reticulata as the maternal parents. These results indicated that C. pitardii, the allotetraploid and allohexaploid C. reticulata may serve as good potential maternal parents for the cross breeding of Camellia.

Mimosa subseries Dolentes Barneby and Brevipedes Barneby are ecologically and morphologically high-diversified infrageneric taxa of this genus in southern South America. We performed a cytogenetical and morphological analysis of both subseries. Chromosome numbers from accessions throughout the area of distribution were studied. The chromosome numbers 2n = 8x = 104 for M. dolens subsp. callosa (Benth.) Barneby, M. dolens subsp. acerba varieties acerba (Benth.) Barneby, latifolia (Benth.) Barneby and rudis (Benth.) Barneby, M. dolens subsp. rigida var. rigescens (Benth.) Barneby, var. anisitsii (Lindm.) Barneby and var. foliolosa (Benth.) Barneby∼ and 2n = 4x = 52 for M. sceptrum Barneby, M. aff. custodis Barneby and M. dolens var. pangloea Barneby are presented for the first time. Their karyotypes were symmetric, with small chromosomes. There were several areas with taxa growing in sympatry, occasionally with intermediate forms. No diploids were found, which suggests the presence of either a declining polyploid complex or ancient polyploidy in the clade of southernmost representatives of M. series Mimosa, the most derived of the genus. Some vegetative, inflorescence and carpological characters seem to be associated with chromosome duplication. The distribution pattern of the cytotypes suggests events of chromosome duplication in centres of diversity and expansion of octoploids to the southernmost areas of distribution. Our findings support the importance of polyploidy in the morphological diversity, distribution and speciation of this complex. Fil: Morales, M.. Universidad de Morón; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina Fil: Fradkin, Maia. Universidad Nacional de Lomas de Zamora; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Bessega, Cecilia Fabiana. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Poggio, Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; Argentina Fil: Fortunato, Renée Hersilia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina. Universidad de Morón; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

12 p., mapas, tablas, gráf. -- Post-print del artículo publicado en Flora - Morphology, Distribution, Functional Ecology of Plants. Versión revisada y corregida., Lilium lancifolium, the tiger lily, constitutes a polyploid complex with both diploids (reproduced by seeds and bulbils) and triploids (propagated exclusively via bulbils). An autopolyploid origin for the triploid forms has been previously suggested based on classical cytogenetics, chromosome mapping techniques, ecological data, and geographic distribution in their native range (Korea and the Japanese Tsushima Island). Using 13 allozyme loci, we comparatively assessed clonal structure and levels of genetic diversity in four diploid and 11 triploid populations in South Korea to test the autopolyploid origin of the triploid cytotype and to infer which seedling recruitment strategy is operating within the diploid populations. We also employed ecological niche modeling and multivariate analysis to determine whether triploids of L. lancifolium occupy different and broader niches to those of diploids in Korea and Tsushima Island. The diploids harbored higher levels of within-population genetic diversity than triploids, and allele profiles found in triploids were exactly subsets of those in diploids. Repeated seedling recruitment was inferred for the diploids, whereas all the studied triploid populations were monoclonal since there is no seedling (sexual) recruitment. Although we found no niche divergence between cytotypes of L. lancifolium, the triploids have a broader niche breadth. Genetic data further confirm the autotriploid origin of L. lancifolium, and the lack of a clear, strong evidence for niche divergence between cytotypes of L. lancifolium supports the view that ecological differentiation is not a pre-requisite for the establishment of new polyploid lineages., This research was supported by the Basic Science Program through the National Research Foundation of Korea (NRF-2013R1A1A2063524) funded by the Ministry of Education, Science and Technology, the Republic of Korea to M.G.C.

Aspidistra subrotata Y. Wan & C.C. Huang, 1987 is considered for the first time as a widespread polyploidy complex in the genus Aspidistra Ker Gawler, 1823 from limestone areas of Asia. The chromosome number of the tetraploid is 2n = 76 and the karyotype is formulated as 2n = 44 m + 8 sm + 24 st, while the chromosome number of the diploid is 2n = 38 and the karyotype formula 2n = 22 m + 4 sm + 12 st. In our studies, diploids occupy broader geographical and environmental niche spaces than tetraploids. Although the leaf-shape of Aspidistra subrotata varies quantitatively between and within diploid and/or tetraploid population(s), no obvious discontinuity in the width of leaf has been observed. The tetraploid plants may be distinguished from the diploid plants by their rigid petioles as well as thick deep green lamina. Aspidistra subrotata is therefore an interesting material to explore the formation and the evolutionary dynamics of a natural polyploid complex from limestone areas of the tropical regions.

The genus Leucanthemum Mill. is a species-rich polyploid complex of southern and central Europe, comprising 41 species with ploidy levels ranging from 2x to 22x. The Leucanthemum pluriflorum clan, a geographically isolated species group of the NW Iberian Peninsula, comprises the diploid L. pluriflorum, the tetraploids Leucanthemumircutianum subsp. pseudosylvaticum and Leucanthemum×corunnense (being a putative hybrid taxon based on a cross between L. pluriflorum and Leucanthemummerinoi), and the two hexaploids Leucanthemumsylvaticum and L. merinoi. In order to reconstruct the evolutionary history of this species group, we analysed sequence variation at the external transcribed spacer region of the nuclear ribosomal repeat (nrDNA ETS) for its members and for a number of other diploid species of Leucanthemum. Our results indicate that there are two major ETS ribotypes present in Leucanthemum, with some of the diploid species fixed for either of the two types and several species (among them L. pluriflorum) exhibiting both types. This polymorphism at the nrDNA ETS locus suggests either gene flow among some of the diploid species (possibly via polyploids) or a homoploid hybrid origin of some of those diploids. Additionally, patterns of ETS ribotype sharing among populations of the four species of the L. pluriflorum clan suggest that the tetraploid L. ircutianum subsp. pseudosylvaticum and the hexaploids L. sylvaticum and L. merinoi have an allopolyploid origin with L. pluriflorum as the maternal parent. Eco-climatological modelling of present and past (last glacial maximum, LGM) distribution areas of the members of the L. pluriflorum clan indicates that the diploid L. pluriflorum may have undergone geographical differentiation into northern (Galician) and southern (central Portuguese) coastal lineages that could account for the two chloroplast haplotype groups observable in the tetra- and hexaploids. Later climatic changes in the Holocene could then have led to the extinction of southern diploid lineages. A distinct overlap of present and past (LGM) potential distribution ranges of L. pluriflorum with those of the N Iberian endemics Leucanthemumgallaecicum and Leucanthemumgaudinii subsp. cantabricum may indicate that one of the latter species may have acted as the paternal parent in the formation of the polyploids of the clan.

† Background and Aims The genus Leucanthemum is a species-rich polyploid complex from southern and central Europe, comprising 41 species with ploidy ranging from 2x to 22x. The present contribution aims at reconstructing the evolutionary history of a geographically isolated species group (the L. pluriflorum clan) from the north-west Iberian Peninsula comprising the diploid L. pluriflorum, the tetraploids L. ircutianum subsp. pseudosylvaticum and L. × corunnense (a putative hybrid taxon based on crossing between L. pluriflorum and L. merinoi), and the hexaploids L. sylvaticum and L. merinoi. † Methods Chromosome number variation (determined flow cytometrically) and sequence variation were analysed for two intergenic spacer regions on the plastid genome ( psbA-trnH and trnC-petN) for individuals from 54 populations in combination with amplified fragment length polymorphism (AFLP) fingerprinting of 246 representative individuals from these populations. † Key Results Plastid sequence data revealed that all surveyed members of the L. pluriflorum clan possess plastid haplotypes that are closely related to each other and distinctly separated from other Leucanthemum species. AFLP fingerprinting resulted in allopolyploid fragment patterns for most of the polyploid populations, except for the tetraploid L. × corunnense and a further tetraploid population in northern Galicia, which cluster with the diploids rather than with the other polyploids. In silico modelling of (auto)tetraploid AFLP genotypes further corroborates the allopolyploid nature of L. ircutianum subsp. pseudosylvaticum, L. sylvaticum and L. merinoi. † Conclusions The present study provides evidence for recognizing one diploid (L. pluriflorum), one autotetraploid (L. corunnense), one allotetraploid (L. pseudosylvaticum) and one allohexaploid (L. sylvaticum with the two geographically and ecologically differentiated subspecies subsp. sylvaticum and subsp. merinoi) in the L. pluriflorum clan. It also has implications for the understanding of biogeographical patterns in the Iberian Peninsula.

A detailed knowledge of the geographical distribution of cytotypes within and between species comprising a polyploid complex is critical to our understanding of the history and evolution of such complexes. In the present study we examined the geographical distributions of cytotypes within six tentatively delimited species comprising the Chrysanthemum indicum complex in China. We determined the ploidy of 188 individuals sampled from 47 populations, based on DNA content using flow cytometry. In addition, chromosome counts were made on samples of each taxon. We confirmed that all samples of C. rhombifolium and C. lavandulifolium were diploid (2n = 18), those of C. hypargyrum and C. potentilloides were tetraploid (2n = 36), and those of C. vestitum were hexaploid (2n = 54). In contrast, we confirmed that C. indicum contained both diploid and tetraploid cytotypes. We found that in addition to marked differences in genome size between ploidy levels, there was a variation in genome size between species of the same ploidy level. Although the diploid, tetraploid, and hexaploid taxa of the complex, as well as the diploid form of C. indicum, occurred only in central and northern China, the tetraploid form of C. indicum was widespread both north and south of the Yangtze River. We suggest that the tetraploid form of C. indicum may have expanded its range southward during recent Quaternary glacial periods when forests retreated in south China as conditions became drier.

Hybridization is particularly likely to occur in initial and young polyploid complexes, and interspecies hybridization between diverged species usually leads to a complicated reticulate evolution. The Ranunculus cantoniensis complex and its allied species include R. chinensis (2x), R. silerifolius var. silerifolius (2x), R. cantoniensis (4x), R. trigonus (2x), R. shuichengensis (2x), R. diffusus (4x), R. repens (4x), R. vaginatus (5x) and R. sieboldii (6x, 8x). Many morphological intermediates can be found between the members of this complex, and the relationship among members is complicated. By analyzing internal transcribed spacers and nrDNA FISH (fluorescence in situ hybridization) signals, we unraveled the phylogenetic and genetic constitution of the various taxonomic units of this complex. Haplotypes were highly separated by median-joining network analysis and at least four haplogroups emerged in which there were 11 primary haplotypes; six out of ten taxa shared haplotype 1, suggesting that haplotype 1, a variation of the primary haplotype R. chinensis, served as the pivotal genome in the complex. The pollen characteristics and electrophoretic patterns of R. vaginatus (5x) showed it to be an intermediate between R. diffusus (4x) and R. sieboldii (6x). The distribution of R. vaginatus (5x) was located at the junction of the distributions of R. diffusus (4x) and R. sieboldii (6x). Ranunculus vaginatus (5x) shared haplotypes 7 and 8 with R. diffusus (4x), and haplotypes 8 and 9 with R. sieboldii (6x). This proved that R. vaginatus (5x) emerged from hybridization between R. diffusus (4x) and R. sieboldii (6x). The results of FISH also support a hybrid origin of R. vaginatus (5x). The findings of this study clearly show that there are only eight taxa in this polyploid complex including R. chinensis (2x), R. silerifolius var. silerifolius (2x), R. trigonus (2x), R. silerifolius var. dolicanthus(2x), R. cantoniensis (4x), R. diffusus (2x), R. vaginatus (5x) and R. sieboldii (6x, 8x). These taxa associated with each other by hybridizing with the pivotal genome. Ranunculus cantoniensis (4x) and R. vaginatus (5x) arose from hybridization events between diverged species in the polyploid complex, leading to a complicated reticulate evolution.

In order to assess the effects of polyploidisation on distribution patterns of species in a polyploid complex, we compared potential and actual distribution ranges of representatives from the genus Leucanthemum Mill. (Compositae, Anthemideae), which occur on the Iberian Peninsula with 20 taxa spanning ploidy levels between 2 n = 2 x = 18 and 2 n = 22 x = 198. Actual distribution ranges of taxa were derived from geo-referenced herbarium specimens by defining buffer circles around the collection localities to account for geographical uncertainties and haphazardness of specimen collecting. Eco-climatologically potential ranges were modelled with the maximum entropy method (Maxent) based on the actual distributions. By comparison of sizes of realised and eco-climatologically potential areas for each taxon we computed taxon-specific overlap indices that express the filling of eco-climatological niches. The correlation between overlap indices and ploidy levels was tested by Spearman's rank correlation coefficient. We observed a significant negative correlation between ploidy level and sizes of realised distribution ranges and no significant correlation of ploidy level and sizes of potential ranges. Finally, we found that diploid and low-ploidy taxa are filling their potential eco-climatological distribution ranges more exhaustively than highly polyploid taxa. Assuming that ascending polyploidisation is the prevailing mode compared to descending polyploidisation, our results demonstrate that the distribution patterns of members of the Leucanthemum polyploid complex on the Iberian Peninsula are mainly influenced by the age of taxa and not by ecological advantages or disadvantages connected with polyploidy.

To reconstruct the evolutionary history of the polyploid southern and central European genus Leucanthemum, comprising 41 species with ploidy levels ranging from 2x to 22x, we analysed chloroplast DNA sequence variation (psbA-trnH and trnL-trnF intergenic spacer regions) of 106 representatives belonging to 30 species and 41 taxa. In an unrooted haplotype network, which shows internal (ancestral) haplotypes that are mainly represented by diploid taxa (L. gallaecicum, L. gracilicaule, L. halleri, L. laciniatum, L. lithopolitanicum, L. rotundifolium, and L. tridactylites), we identified three major haplotype groups (HTGs) containing diploid and polyploid species. Whereas HTG I contains most of the polyploid taxa of the genus, with a single diploid species from the SW Alps (L. virgatum), HTG II consists of four diploid (L. burnatii, L. gaudinii, L. graminifolium, and L. vulgare) and six polyploid species, and HTG III comprises one diploid (L. pluriflorum) and three polyploid species endemic to the NW part of the Iberian Peninsula. We also further found evidence for recurrent formation of at least three polyploid taxa (i.e., L. delabrei, L. ircutianum subsp. cantabricum, and L. pallens).

[EN] Polyploidy and hybridisation are the basis of the evolution of Centaurea (Compositae). At the El Saler dune field (eastern Spain), the diploid Centaurea aspera ssp. stenophylla and the tetraploid C. seridis ssp. maritima form a polyploid complex in which C. x subdecurrens individuals occur. This polyploid complex was analysed morphologically and genetically, using random amplified polymorphic DNA (RAPD) and tubulin-based polymorphism (TBP) markers. Flow cytometry showed that the hybrids are triploid, which is a rare finding in Centaurea. Morphologically, in contrast to leaf characters, flowering characters clearly discriminated the three taxa. The genetic analyses confirm that C. x subdecurrens is a result of the hybridisation between Centaurea aspera ssp. stenophylla and C. seridis ssp. maritima, and suggest that backcrossing events and gene flow are very rare or absent. Although the hybrids likely represent true F1 offspring, they displayed some genetic diversity that is probably due to the combination of alleles. Genetic diversity was higher in diploid than in tetraploid individuals. This fact, and the high degree of sterility of the triploid hybrids, may reflect a cytotype minority exclusion effect. This may cause spatial segregation, which effectively takes place in the study area. Dune disturbance may lead to an overlapping of the parents' distribution areas, facilitating hybridisation., This work is posthumously dedicated to Antonio Samo Lumbreras, to whom we are very grateful for all his help. This study was sponsored by the Valencian Government (Research Project GVPRE/2008/130) and the Universitat Politecnica de Valencia (Research Project Ref. 3241).

Español. Se presenta un estudio sobre la malformación polínica en Ranunculus grex parnassiifolius, un complejo poliploide cuya distribución va desde las montañas del noroeste de la Península Ibérica hasta la mayor parte de los macizos alpinos. El resultado más notable es la baja viabilidad de polen en las poblaciones tetraploides (85,27% de polen no viable) en comparación con las poblaciones diploides (17,72%); y se considera como una prueba de la existencia de procesos reproductivos parcialmente apomícticos.English. Asurvey of pollen malformation in Ranunculus grex parnassiifolius, a polyploid complex distributed from the northwestern mountains of the Iberian Peninsula to the most alpine massifs, is presented. The most remarkable result is the low viability of pollen in tetraploid populations (85.27% of nonviable pollen) compared to diploid populations(17.72%); and is considered as a proof ofthe existence of partial reproductive apomictic processes.

Ivy ( Hedera spp., Araliaceae) is a polyploid complex of woody vines. Native to Eurasia and northern Africa, ivy is cultivated worldwide and has become an aggressive invader of North American forests. Despite its ecological impacts and economic significance to the horticultural industry, the taxonomy of Hedera is controversial and historical relationships are poorly defined. Here we characterize the phylogeny of Hedera based on the low-copy nuclear locus Granule-bound starch synthase I ( GBSSI ) and twelve non-coding cpDNA regions. Maximum parsimony and Bayesian analyses of both data sets identified Hedera as monophyletic. For GBSSI , we isolated eighteen haplotypes that were widely shared across species. There was no evidence of fixed heterozygosity or haplotype additivity in polyploids, suggesting pos- sible autopolyploid origins. For cpDNA, we isolated sixteen haplotypes that were highly structured by geography. Haplotype diversity and phylogenetic structure were greatest in northern Africa and southern Europe. Thus, while most members of the Araliaceae reside in tropi- cal and subtropical Asia, the early diversification of Hedera probably occurred in the Mediterranean Basin. Geographically-structured clades included diploid and polyploid species, suggesting that genome duplication has occurred repeatedly in the genus. Closely-related ivies often differed in leaf size and trichome morphology, indicating evolutionary lability of traits traditionally used for classification. Nonetheless, we recovered similar or identical DNA sequences within morphologically-defined species. Notable exceptions included southern populations of H. helix ( H. helix subsp. caucasigena and H. helix subsp. rhizomatifera ) that had cpDNA haplotypes distinct from those of central and northern Europe ( H. helix subsp. helix ).

The orophilous plant, Ranunculus parnassiifolius L., is a polyploid complex that is widespread throughout the southern European mountains, where at least five taxa have traditionally been recognized. The aim of this study was to test whether R. parnassiifolius subsp. cabrerensis should be treated as an independent species of the R. parnassiifolius polyploid complex and constitutes, therefore, an evolutionary line in itself. To disentangle its evolutionary history and taxonomy, we used genome size estimation based on flow cytometric measurements (FCM), multivariate morphometric analyses, polymerase chain reaction-restriction fragment length polymorphisms (PCR–RFLPs) and subsequent sequencing of cpDNA regions (trnS, trnR-atpA, atpH-atpI). This study provides molecular and morphological evidence for the recognition of R. cabrerensis at the species level, rather than as an intraspecific taxon of R. parnassiifolius. Furthermore, it is concluded that those plants previously known as R. parnassiifolius subsp. muniellensis should be systematized at the subspecies level as R. cabrerensis subsp. muniellensis. This contribution highlights the benefit of combining diverse approaches to obtain knowledge about relict populations and for the implementation of suitable conservation measures.

Turnera ulmifolia constitutes a well-studied polyploid complex with allo- and autopolyploid species ranging from 2 to 8x. Flow cytometry was used to determine nuclear DNA content, and to estimate 2C- and 1Cx-values with the aim of analysing the genome size in Turnera in terms of polyploid speciation. The 2C-value and 1Cx-value were evaluated in 12 species of the T. ulmifolia complex. Nuclear DNA content was estimated by flow cytometry of nuclei stained with propidium iodide. The 2C DNA content ranged from 1.38 to 1.83 pg in diploids, from 2.67 to 3.96 pg in tetraploids, from 2.73 to 4.31 pg in hexaploids, and from 3.53 to 5.90 pg in octoploids. The 1Cx-value ranged from 0.44 to 0.99 pg. The Turnera ulmifolia complex showed an increase in total DNA content in the ploidy level, but not in the expected proportion. The general tendency indicated a decrease in the 1Cx-value with increasing chromosome number, with T. grandidentata 4x being an outstanding exception. The 1Cx-values in the allooctoploids T. aurelii and T. cuneiformis differed by 1.6-fold from each other, probably as a result of different evolutionary histories following divergence from the last common ancestor. Fil: López, Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Panseri, Andrea Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Poggio, Lidia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Fernandez, Aveliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina

Aster ageratoides var. pendulus, a recently described taxon, is endemic to Mt Hupingshan of north-western Hunan, China. Field observations and collections were made from the only known population. Root-tip squashes were used to determine the chromosome numbers of 96 plants and 61 seedlings from the achenes of eight sample plants. The results show that var. pedulus is a swarm of 30 cytotypes with nearly continuous chromosome numbers from 2n = 60 to 2n = 92. Chromosome numbers of 61 seedlings vary from 2n = 61 to 2n = 91, belonging to 18 cytotypes. The chromosome number variation of var. pendulus is highly unusual not only in the A. ageratoides polyploid complex but also in angiosperms. Such an enormous continuous variation of chromosome numbers could have arisen by the combined effect of hybridization, recent origin and high levels of polyploidy. (C) 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165, 378-387.

Taxonomic complexity may be associated with migration history and polyploidy. We used plastid and nuclear DNA markers to investigate the evolutionary history of the systematically challenging Dactylorhiza maculata polyploid complex. A total of 1833 individuals from 298 populations from throughout Europe were analysed. We found that gene flow was limited between the two major taxa, diploid ssp. fuchsii (including ssp. saccifera) and tetraploid ssp. maculata. A minimum of three autotetraploid lineages were discerned: (1) southern/western ssp. maculata; (2) northern/eastern ssp. maculata; and (3) Central European ssp. fuchsii. The two ssp. maculata lineages, which probably pre-date the last glaciation, form a contact zone with high genetic diversity in central Scandinavia. Intermediate plastid haplotypes in the contact zone hint at recombination. Central Europe may have been a source area for the postglacial migration for the southern/western lineage of ssp. maculata, as well as for ssp. fuchsii. The northern/eastern lineage of ssp. maculata may have survived the LGM in central Russia west of the Urals. The tetraploid lineage of ssp. fuchsii is indistinguishable from diploid ssp. fuchsii, and is probably of postglacial origin. The Mediterranean region and the Caucasus have not contributed to the northward migration of either ssp. fuchsii or ssp. maculata. (Less)

Jacobaea vulgaris subsp. vulgaris constitutes an intricate polyploid complex distributed in Europe. Four chromosome numbers have been reported in this species: 2n=20, 40, 80 and 32. Chromosome number 2n=20 reported from Bulgaria is due to misidentification with J. aquatica. We discovered new hexaploid (2n=6x=60) cytotype occuring within four sympatric populations of otherwise tetraploid and octoploid plants in the Czech Republic, Slovakia and Ukraine. The frequency of hexaploid individuals within 76 studied populations is very low (only 10 of 693 analysed plants), and hexaploids probably represent hybrids between tetraploid and octoploid plants. Multivariate morphometric analysis reveals partial separation of tetraploid and octoploid plants, whereas hexaploid individuals are similar to octoploids. Octoploids and hexaploids exhibit slightly longer ray florets, involucral bracts and tubular florets and more hairy outer achenes. Hexaploid plants display larger pollen grains and lower pollen fertility.

Estudos citogeneticos no genero Passiflora tem reportado o numero cromossomico, a caracterizacao do cariotipo e o conteudo de DNA nuclear. Entretanto, a maioria das analises se limita ao numero cromossomico e as especies dos subgeneros Passiflora e Decaloba . Assim, diferentes autores apontam a necessidade de expandir as informacoes acerca do cariotipo de mais especies, especialmente para os subgeneros Astrophea e Deidamioides. O objetivo foi ampliar a caracterizacao do cariotipo e mensurar o DNA nuclear de especies representantes dos quatro subgeneros. O numero cromossomico determinado para 30 especies, 13 ineditas, variou: sete especies do subgenero Decaloba com 2n=2x=12, 16 do subgenero Passiflora com 2n=18 e uma com 2n=20 ( P. foetida ), quatro do subgenero Astrophea com 2n=4x=24, uma do subgenero Deidamioides com 2n=4x=24 ( P. arbelaezii ) e outra com 2n=8x=48 ( P. contracta ). A caracterizacao citogenetica foi conduzida pela primeira vez para 29 especies. Cromossomos metacentricos e submetacentricos predominaram no cariotipo, e duas especies do subgenero Astrophea ( P. lindeniana e P. arborea ) apresentaram um par acrocentrico. O valor 2C nuclear de 41 especies oscilou entre 2C=0,59 pg ( P. capsularis – Decaloba ) a 2C=5,46 pg ( P. quadrangularis – Passiflora ), sendo encontradas discrepâncias de ate 800%. Algumas especies tiveram valores 2C identicos, como P. auriculata ( Decaloba ) e P. coccinea ( Passiflora ) com 2C=2,00 pg, e P. arborea ( Astrophea ) e P. tripartita ( Passiflora ) com 2C=2,53 pg. Com base nos resultados foi possivel separar o subgenero Decaloba dos demais pelo numero cromossomico, nivel de ploidia e tamanho de genoma estatisticamente menor. O subgenero Passiflora foi discriminado pelo numero cromossomico. Entretanto, o nivel de ploidia nao foi determinado em virtude dos eventos de poliploidizacao seguido por disploidia reducional que ocorreram no cariotipo dessas especies ao longo da evolucao. Astrophea e Deidamioides possuem mesmo nivel de ploidia e valores 2C estatisticamente identicos, porem foram distinguidos dos demais subgeneros pelo numero cromossomico e nivel de ploidia. Destaque para P. contracta que mostrou o dobro do tamanho do genoma nuclear (2C=4,78 pg) e uma condicao octaploide. Portanto, os dados, conjuntamente ou nao, foram importantes como marcadores taxonomicos no genero Passiflora , corroborando com dados previos obtidos por meio da citogenetica classica e molecular.

Ludwigia, a genus with rampant interspecific hybridization, is an ideal model for examining the impact of gene introgression and polyploidization on species diversification. We examined the evolution of the Ludwigia sect. Isnardia, which is a polyploid complex (x = 8) of five species distributed in North America. The phylogeny of L. sect. Isnardia was reconstructed based on sequences of cpDNA atpB-rbcL intergenic spacer and nrITS (internal transcribed spacer). Most L. sect. Isnardia species are polyphyletic at both loci, indicating possible recurrent hybridization, based on maximum likelihood trees rooted at L. sect. Microcarpium. A minimum spanning network was also constructed to examine genealogical relationships among haplotypes. In the cpDNA network, haplotypes of tetraploid L. spathulata are nested at the most interior nodes, suggesting a parental genome origin of an extinct diploid or an unsampled extant diploid with a DD cytotype. Allopolyploid L. arcuata contributed its cpDNA to hexaploid L. repens and L. brevipes. ITS haplotypes of diploid L. palustris were clustered with L. spathulata, suggesting L. palustris as the paternal genome donor. Ludwigia brevipes may have arisen via bi-directional hybridization between L. palustris and L. arcuata followed by polyploidy. Genetic and phylogenetic analyses using molecular markers with different inheritance modes provided sufficient insights into the reticulate evolution of the species of L. sect. Isnardia. Interspecific hybridization and polyploidy play a key role in the species evolution in L. sect. Isnardia.

Uniparental reproduction has often been regarded as advantageous for colonization. In pseudogamous a pomicts, reproduction via single individuals requires self-pollination and consequently self-compatibility (SC) for production of viable seeds. SC and reproductive fitness have been studied in diploid and polyploid taxa of the Ranunculus auricomus complex via pollinator exclusion tests, assessment of seed set, and germination rates. Reproductive fitness of sexuals exceeds that of apomicts and of F(1) hybrids but may fluctuate more strongly between years than is the case in apomicts. Diploid sexual taxa and also their F(1) hybrids are completely self-incompatible (SI). Auto-polyploid sexual cytotypes are also predominantly SI, which may have restricted their range expansion. The observed breakdown of SI in the rather widespread allohexaploid apomicts may be explained by initial partial SC inherited from semi-self-compatible ancestors and strong selection for SC genotypes. It is concluded that higher reproductive fitness of sexuals may help to maintain sexual populations when cross-pollination is available, whereas SC in apomicts may be advantageous in temporally and spatially unstable environments and also for colonization events. Results suggest that SC in connection with pseudogamous apomixis is an important factor for the observed distribution pattern of geographical parthenogenesis.

Chromosome banding techniques (Giemsa and fluorochrome staining) were used to investigate Ornithogalum umbellatum L., O. angustifolium Bor. and 11 related taxa. Nine different basic Q-banding patterns, referred to as genomes, could be recognised. These patterns are indicated by capitals (A–E, P–S). Six of the nine basic genome types can be subdivided into different subtypes. The B genome was found in the two bulbilliferous species, i.e. O. umbellatum and O. angustifolium. It occurs in a number of combinations together with the A, C, D and E genomes. Genome combinations of these five basic types were found in seven species. Six of them share morphological characteristics. These species are: O. monticolum Jord. & Fourr., O. baeticum Boiss., O. angustifolium, O. refractum, Kit., O. umbellatum and O. algeriense Jord. & Fourr. A seventh species, O. platyphyllum Boiss., in which the E genome occurs, can be regarded as an intermediate between this complex and the O. montanum group. Each species is treated extensively; its morphology, geographical distribution, chromosome number and banding patterns are discussed separately. A model of the probable course of the evolution in this complex during the last two glaciation periods is described. In this model attention is paid to ecological differentiation, migration leading to the present distribution patterns, hybridization followed by polyploidization and to fixation, which may be the result of chromosomal rearrangements that prevent regular meiosis. Some cytotypes, formerly regarded as O. umbellatum, are now classified in other species. A second polyploid complex in which these species occur, is probably more widely distributed in south-eastern Europe than is generally thought at present. The species O. exscapum Ten., O. nivale Boiss., O. comosum L., O. collinum Guss. and O. gussonei Ten. p.p. are components of this complex. The delimitation of this complex as a whole and the relationship between its diploid and polyploid components have still to be clarified.

Anthoxanthum alpinum Love & Love has been described as a diploid perennial distributed in northern Eurasia and the high mountains of central and eastern Europe. Difficulties in finding reliable morphological differences between this taxon and the widespread tetraploid Anthoxanthum odoratum L. have resulted in taxonomists treating them as conspecific, despite the cytological differentiation. The purpose of this study was to use different approaches to assess the relationships between close congeners, such as the pair A. odoratum/A. alpinum. Macromorphological, micromorphological, and molecular data were gathered and analysed for 14 populations representing both taxa from Scandinavia and the Iberian Peninsula. Different cluster analyses were performed to study the relatedness between individuals and populations. Subsequently, a principal components analysis was computed on the basis of macromorphological quantitative traits, and principal coordinates analysis was used to analyse qualitative, micromorphological, and random amplification of polymorphic DNA (RAPD) data. An analysis of molecular variance was applied to the molecular data, and the genetic differentiation between samples was measured using the FST estimator. The results showed that the geographical origin was more important than the ploidy level in explaining the relatedness between specimens and populations. Moreover, a strong correlation was found between the micromorphological traits and environmental parameters. The results of the analyses do not support the assignment of a specific taxonomic rank to A. alpinum. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 156, 237–252.

Bidens pilosa is a medicinal species from the Asteraceae family, with a wide geographical distribution, found all over Brazil. There are no reports on chromosomal studies from the Brazilian South. Mitotic chromosomes, meiotic behavior, and pollen viability were studied in 6 populations of B. pilosa from Rio Grande do Sul State, Brazil, using conventional staining with acetic orcein 2%. The populations include cytotypes with a variable number of chromosomes: 2n=36, 2n=48 and 2n=54, indicating polyploidy and aneuploidy. The meiotic process was considered regular, even though irregular chromosomal pairing appeared, which is normal in cytotypes from a polyploid complex. The irregularities observed were mainly on univalent, trivalent, and tetravalent pairing associations. However, the pollen viability estimative was high.

A phylogenetic study of the genus Polycarpon was made using DNA sequence data from the chloroplast rpsl6 intron and nuclear RPB2 regions. Polycarpon as currently recognised is shown to be polyphyletic. The South American species P. coquimbense and P. suffruticosum are more closely related to Haya obovata (Socotra) and Polycarpaea spicata (paleotropical) than to the remaining species of Polycarpon, and the widespread tropical species P. prostratum is nested with Macaronesian species of Polycarpaea. All three should therefore be excluded from Polycarpon. The remaining species, the P. tetraphyllum group, has its main diversity in the Mediterranean region. It is a polyploid complex with morphologically very similar taxa mostly separated only by partially overlapping characters. The members of this group form a strongly supported, but largely unresolved clade. It is proposed that they are all included in a widely circumscribed P. tetraphyllum. The dehiscence of the capsules in P. tetraphyllum, by valves that elastically roll inwards and finally throw out the seeds, is unique in Caryophyllaceae and provides a strong synapomorphy for Polycarpon in this new restricted sense.

The genus Anthoxanthum s.I. (including Hierochloe) (Poaceae, Pooideae, Aveneae) comprises 35-50 species and has a cosmopolitan distribution. Anthoxanthum alpinum was described as a diploid perennial that is distributed in northern Eurasia and in the high mountains of central and eastern Europe. Difficulties in finding reliable morphological differences between this taxon and the widespread tetraploid A. odoratum have resulted in taxonomists treating them as conspecific, despite the cytological differentiation. The purpose of this study was to provide information that may help clarify the relationships between these taxa. Macromorphologial, micromorphological, and anatomical data were gathered and analyzed for 14 populations representing both taxa from Scandinavia and the Iberian Peninsula. Statistical analyses were carried out to identify the most useful characters for taxonomy. The relationships among samples were based on different similarity coefficients and summarized using UPGMA clustering methods. The results show that geography has more statistical weight than ploidy level in explaining the relatedness among individuals and populations. A strong correlation between leaf micromorphological/anatomical characters and environmental parameters was detected. The results of the analyses do not support recognition of A. alpinum as a distinct species.

Premise of the study: Microsatellites were developed in the vulnerable African rainforest tree Afzelia bipindensis to investigate gene flow patterns. Methods and Results: Using 454 GS-FLX technique, 16 primer sets were identified and optimized, leading to 11 polymorphic and readable markers displaying each six to 25 alleles in a population. Up to four alleles per individual were found in each of the loci, without evidence of fixed heterozygosity, suggesting an autotetraploid genome. Cross-Amplification succeeded for all loci in the African rainforest species A. pachyloba and A. bella ,which appeared tetraploid, and for most loci in the African woodland species A. africana and A. quanzensis ,which appeared diploid, but failed in the Asian species A. xylocarpa Flow cytometry confirmed the suspected differences in ploidy. Conclusions: African Afzelia species are diploid or tetraploid, a situation rarely documented in tropical trees. These newly developed microsatellites will help in the study of their mating system and gene flow patterns., SCOPUS: ar.j, info:eu-repo/semantics/published

Environmental sex determination is present in several animal and plant lineages, in which gender depends on diverse factors such as temperature, light and water availability. This study examines effects of water availability and pheromones on the production of female and male organs by three fern species adapted to dry habitats. Isolated individuals become first female and then bisexual, irrespective of the degree of soil moisture, and, consequently, may self-fertilize. However, female individuals release pheromones that induce maleness in nearby individuals, thus favouring cross-fertilization., Environmental sex determination (ESD) is present in several animal and plant lineages. Diverse factors such as temperature, light or water availability have been described as sex determinants in these organisms. Among plants, ferns frequently display ESD. This work compares the effect of different levels of water availability in two diploid species of the xerophytic fern genus Cheilanthes and in their derived tetraploid, and if they are sensitive to antheridiogen (i.e. maleness-inducing pheromone). Different watering regimes were applied to isolated gametophyte cultures of the three study species. Gametophyte survival, size, gender and sporophyte production were assessed after 13, 18 and 23 weeks of culture. Cultures combining spores and adult gametophytes were established to test the effect of antheridiogen. Isolated gametophytes had an asexual to female to bisexual sequence that did not depend upon the degree of soil moisture. Both gender expression and growth reduction in response to water scarcity of the allotetraploid were more similar to those of one of the diploid parents. In all watering regimes, survival was higher in the allotetraploid, suggesting hybrid vigour, whereas automixis rate was similar in the three species and reached ∼50 % at high moisture. This breeding system can ensure reproduction in the absence of males. In the three species, female gametophytes produced antheridiogens that enhanced maleness. This promotes a mixed mating system that could be favourable for ferns growing in xeric habitats.

[EN] • Premise of the study: Microsatellite primers were developed in the perennial herbs of the diploid-polyploid complex Veronica subsect. Pentasepalae (Plantaginaceae) to investigate the role that hybridization has played in the evolution of the group, which includes several endangered species. • Methods and Results: Twelve pairs of primers leading to polymorphic and readable markers were identifi ed and optimized from V. jacquinii and V. orbiculata using a microsatellite-enriched library method and 454 GS-FLX technique. The set of primers amplifi ed dinucleotide to pentanucleotide repeats, and the number of alleles per locus ranged from one to six, one to 11, and one to nine for V. orsiniana , V. javalambrensis , and V. rosea , respectively. Transferability analyses were performed in 20 species corresponding to 10 different subgenera. • Conclusions: These results indicate the utility of the newly developed microsatellites across Veronica subsect. Pentasepalae , which will help in the study of gene fl ow patterns and genetic structure.

The European–Mediterranean–Oriental Dactylorhiza romana/sambucina polyploid complex was studied with regard to genetic and morphological variation patterns. Allozyme and morphometric data were collected from 24 and 19 populations, respectively, initially identified as D. flavescens, D. insularis, D. markusii, D. romana, D. sambucina, and an indeterminate taxon. Genetic distances were calculated and illustrated by an unweighted pair-group method using arithmetic averages (UPGMA) dendrogram, and principal components analyses (PCAs) were used to summarize morphological variation patterns. Another PCA was performed on combined allozyme and morphometric data. On the basis of the dendrogram and the PCA plots, main groups of populations were delimited, and the probability that each morphological character would distinguish correctly between these groups was estimated. After combining morphometric interpretations with studies of herbarium material and information from the literature, the following taxa were confidently accepted: D. romana ssp. romana, D. romana ssp. guimaraesii (comb. et stat. nov.), D. romana ssp. georgica, D. sambucina, D. cantabrica (sp. nov.), and D. insularis. Levels of genetic diversity suggest that D. romana s.s. is the least derived member of the complex. The evolutionary divergence of the diploid species, D. romana and D. sambucina, was probably the outcome of vicariant speciation, whereas D. romana ssp. georgica and D. romana ssp. guimaraesii appear to have evolved from D. romana s.s. through incomplete vicariant and peripheral isolate speciation events, respectively. In some populations of the diploid taxa, a significant deficiency in heterozygotes was found at one to three loci. It is proposed that this pattern may indicate a Wahlund effect, hypothesizing that local populations are subdivided into demes determined by the commonly sympatric occurrence of two distinct colour morphs combined with partial morph constancy of individual pollinators (bumblebees). Several pathways are possible for the origin of the allotriploid D. insularis and the apparently allotetraploid D. cantabrica. A taxonomic revision is provided. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society, 2006, 152, 405–434.

We examined infrageneric relationships within Phacelia subgenus Phacelia based on phylogenetic hypotheses derived from internal transcribed spacers (ITS) and the 5.8S gene of nuclear ribosomal DNA. Maximum parsimony (MP) and maximum likelihood (ML) phylogenies support the monophyly of sects. Euglypta and Miltitzia, previously hypothesized based on seed characters and ecological distribution. Tree branching patterns within the Euglypta/Miltitzia clade indicate three principle lineages: 1) the P. pachyphylla complex, 2) a clade of P. brachyloba and 3) a clade consisting of two sister groups, the P. affinis complex and the P. fremontii complex. An aneuploid increase in chromosome number occurs from the P. pachyphylla complex (n = 11) to P. brachyloba (n = 12) while the pattern within the P. fremontii complex includes both aneuploid increases and decreases. There is high bootstrap support for monophyly of taxa representing both the P. magellanica polyploid complex and the P. humiles species group; th...