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Sample records for silene species caryophyllaceae

  1. A taxonomic revision of the southern African native and naturalized species of Silene L. (Caryophyllaceae

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    J. C. Manning

    2012-12-01

    Full Text Available The native and naturalized species of Silene L. in southern Africa are reviewed, with full synonomy and the description of two new species from the West Coast of Western Cape. Eight native species and three naturalized species are recognized, including the first identification in southern Africa of the Mediterranean S. nocturna L. The identity of S. aethiopica Burm., which has remained unknown since its description, is established and is found to be the oldest name for S. clandestina Jacq. Patterns of morphological variation within each species are discussed and subspecies are recognized for geographically segregated groups of populations that are ± morphologically diagnosable. The following new names or combinations are made among the southern African taxa: S. aethiopica subsp. longiflora; S. burchellii subsp. modesta, subsp. multiflora, and subsp. pilosellifolia; S. crassifolia subsp. primuliflora; S. saldanhensis; S. rigens; and S. undulata subsp. polyantha. Each taxon is described, with information on ecology and distribution, and most species are illustrated, including SEM micrographs of the seeds.

  2. Breeding system in the dichogamous hermaphrodite Silene acutifolia (Caryophyllaceae).

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    Buide, M L; Guitian, J

    2002-12-01

    The breeding system of the dichogamous hermaphrodite species Silene acutifolia, endemic to north-west Spain and north and central Portugal, is examined. Pollen germinability and style-stigma receptivity were analysed to determine whether protandry is a barrier to self-fertilization. By 48 h after anthesis, pollen germinability had declined to approx. 10 %. The short straight styles are not receptive when flowers first open. They gradually elongate and curve outwards, develop stigma papillae and become receptive. There is no clear separation between stigma and style: the stigma papillae appear in a line along the length of the style. Fruit set is high regardless of pollen source; however, seed set is significantly reduced after both spontaneous and facilitated autogamy. Seed set following spontaneous autogamy was 30 % (86 % in controls) in 1998 and 33 % (87 % in controls) in 1999. Seed set following facilitated autogamy was 62 % (86 % in controls) in 1998 and 67 % (89 % in controls) in 1999. Thus, separation of the male and female phases does not prevent production of seeds by self-pollination, although it does reduce the likelihood of this. Furthermore, results of the present experiments indicate that this species has no self-incompatibility mechanisms (self-compatibility index = 0.98). The selfing rate in the study population was 0.41, which is supported by the lack of self-incompatibility systems and by the incomplete protandry. Copyright 2002 Annals of Botany Company

  3. The complete chloroplast genome sequences of Lychnis wilfordii and Silene capitata and comparative analyses with other Caryophyllaceae genomes.

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    Kang, Jong-Soo; Lee, Byoung Yoon; Kwak, Myounghai

    2017-01-01

    The complete chloroplast genomes of Lychnis wilfordii and Silene capitata were determined and compared with ten previously reported Caryophyllaceae chloroplast genomes. The chloroplast genome sequences of L. wilfordii and S. capitata contain 152,320 bp and 150,224 bp, respectively. The gene contents and orders among 12 Caryophyllaceae species are consistent, but several microstructural changes have occurred. Expansion of the inverted repeat (IR) regions at the large single copy (LSC)/IRb and small single copy (SSC)/IR boundaries led to partial or entire gene duplications. Additionally, rearrangements of the LSC region were caused by gene inversions and/or transpositions. The 18 kb inversions, which occurred three times in different lineages of tribe Sileneae, were thought to be facilitated by the intermolecular duplicated sequences. Sequence analyses of the L. wilfordii and S. capitata genomes revealed 39 and 43 repeats, respectively, including forward, palindromic, and reverse repeats. In addition, a total of 67 and 56 simple sequence repeats were discovered in the L. wilfordii and S. capitata chloroplast genomes, respectively. Finally, we constructed phylogenetic trees of the 12 Caryophyllaceae species and two Amaranthaceae species based on 73 protein-coding genes using both maximum parsimony and likelihood methods.

  4. Inbreeding and oubreeding effects on pollen fitness and zygote survival in Silene nutans (Caryophyllaceae)

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    Hauser, Thure Pavlo; Siegismund, H.R.

    2000-01-01

    inbreeding depression, oubreeding effects, outcrossing, pollen fitness, selfing, Silene nutans, zygote survival......inbreeding depression, oubreeding effects, outcrossing, pollen fitness, selfing, Silene nutans, zygote survival...

  5. Transcriptome and biochemical analysis of a flower color polymorphism in Silene littorea (Caryophyllaceae

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    Inés eCasimiro-Soriguer

    2016-02-01

    Full Text Available Flower color polymorphisms are widely used as model traits from genetics to ecology, yet determining the biochemical and molecular basis can be challenging. Anthocyanin-based flower color variations can be caused by at least 12 structural and three regulatory genes in the anthocyanin biosynthetic pathway. We use mRNA-Seq to simultaneously sequence and estimate expression of these candidate genes in nine samples of Silene littorea representing three color morphs (dark pink, light pink and white across three developmental stages in hopes of identifying the cause of flower color variation. We identified 29 putative paralogues for the 15 candidate genes in the anthocyanin biosynthetic pathway. We assembled complete coding sequences for 16 structural loci and nine of ten regulatory loci. Among these 29 putative paralogues, we identified 622 SNPs, yet only nine synonymous SNPs in Ans had allele frequencies that differentiated pigmented petals (dark pink and light pink from white petals. These Ans allele frequency differences were further investigated with an expanded sequencing survey of 38 individuals, yet no SNPs consistently differentiated the color morphs. We also found one locus, F3h1, with strong differential expression between pigmented and white samples (>42x. This may be caused by decreased expression of Myb1a in white petal buds. Myb1a in S. littorea is a regulatory locus closely related to Subgroup 7 Mybs known to regulate F3h and other loci in the first half of the ABP in model species. We then compare the mRNA-Seq results with petal biochemistry which revealed cyanidin as the primary anthocyanin and five flavonoid intermediates. Concentrations of three of the flavonoid intermediates were significantly lower in white petals than in pigmented petals (rutin, quercetin and isovitexin. The biochemistry results for rutin, quercetin, luteolin and apigenin are consistent with the transcriptome results suggesting a blockage at F3h, possibly caused

  6. Paronychia manfrediana (Caryophyllaceae), a new species from northeast Greece

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    Tan, Kit; Strid, Arne

    2008-01-01

    Paronychia manfrediana (Caryophyllaceae) is decribed as a species new to science based on material collected near the Turkish border in northeastern Greece; it is illustrated by a photograph. Although belonging to Paronychia sect. Heterosepalae it bears a strong resemblance to P.macedonica (Paron...

  7. Genomic diversity in two related plant species with and without sex chromosomes--Silene latifolia and S. vulgaris.

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    Radim Cegan

    Full Text Available Genome size evolution is a complex process influenced by polyploidization, satellite DNA accumulation, and expansion of retroelements. How this process could be affected by different reproductive strategies is still poorly understood.We analyzed differences in the number and distribution of major repetitive DNA elements in two closely related species, Silene latifolia and S. vulgaris. Both species are diploid and possess the same chromosome number (2n = 24, but differ in their genome size and mode of reproduction. The dioecious S. latifolia (1C = 2.70 pg DNA possesses sex chromosomes and its genome is 2.5× larger than that of the gynodioecious S. vulgaris (1C = 1.13 pg DNA, which does not possess sex chromosomes. We discovered that the genome of S. latifolia is larger mainly due to the expansion of Ogre retrotransposons. Surprisingly, the centromeric STAR-C and TR1 tandem repeats were found to be more abundant in S. vulgaris, the species with the smaller genome. We further examined the distribution of major repetitive sequences in related species in the Caryophyllaceae family. The results of FISH (fluorescence in situ hybridization on mitotic chromosomes with the Retand element indicate that large rearrangements occurred during the evolution of the Caryophyllaceae family.Our data demonstrate that the evolution of genome size in the genus Silene is accompanied by the expansion of different repetitive elements with specific patterns in the dioecious species possessing the sex chromosomes.

  8. Dianthus vanensis (Caryophyllaceae), a new species from Turkey

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    İLÇİM, Ahmet; BEHÇET, Lütfi; MÜKEMRE, Muzaffer

    2013-01-01

    Dianthus vanensis Behçet & İlçim is described as a new species. It is confined to Çatak District (Van) in Eastern Anatolia, Turkey. The diagnostic characters and taxonomic comments on the species are given. Notes are also presented on its ecology. A distribution map of new and related species is also provided.

  9. Dianthus aticii, a new species from Turkey (Caryophyllaceae

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    Ergin Hamzaoğlu

    2015-04-01

    Full Text Available During the taxonomic revision of the Turkish Dianthus species, specimens collected from Bilecik, Seben (Bolu, and Nallıhan (Ankara were discovered that represent a new species. Its description, images, chorology, ecology, and threat category are provided. It was compared with a closely related species, D. zonatus, and differences are based on its general morphology and seed micromorphology.

  10. Dianthus aticii, a new species from Turkey (Caryophyllaceae)

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    Hamzaoğlu, Ergin; Koç, Murat; Aksoy, Ahmet

    2015-01-01

    Abstract During the taxonomic revision of the Turkish Dianthus species, specimens collected from Bilecik, Seben (Bolu), and Nallıhan (Ankara) were discovered that represent a new species. Its description, images, chorology, ecology, and threat category are provided. It was compared with a closely related species, Dianthus zonatus, and differences are based on its general morphology and seed micromorphology. PMID:25931971

  11. New records of Microbotryum species parasitizing Caryophyllaceae from Ukraine

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    Kyrylo G. Savchenko

    2013-12-01

    Full Text Available Four records of smut fungi belonging to the genus Microbotryum Lév.are reported. Two species were found on new hosts, namely M. dianthorum on Dianthus borbasii and D. pseudoserotinus and M. superbum on D. stenocalyx. Microbotryum lagerhemii on Lychnis viscaria is a new species for Ukraine.

  12. Analysis of Chromosome Number in Some Allium and Silene Wild Species with Ornamental Use

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    Lucia DRAGHIA; Elena Liliana CHELARIU; Culiţă SÎRBU; Maria BRÂNZĂ; Cristina SANDU MICULSCHI

    2013-01-01

    The present study analyses the number of somatic chromosomes in plant species with ornamental value, in Romanian indigenous flora, Allium (A. flavum L., A. saxatile Bieb.) and Silene (S. compacta Fischer., S. supina M.Bieb.). The biological material was identified and harvested in the South-Eastern part of Dobrogea (Tulcea and Constanţa counties), area in the South-Eastern part of Romania, situated between the Danube and the Black Sea. Individuals from two populations of Allium flavum and All...

  13. Host-related genetic differentiation in the anther smut fungus Microbotryum violaceum in sympatric, parapatric and allopatric populations of two host species Silene latifolia and S. dioica

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    Van Putten, W.F.; Biere, A.; Van Damme, J.M.M.

    2005-01-01

    We investigated genetic diversity in West European populations of the fungal pathogen Microbotryum violaceum in sympatric, parapatric and allopatric populations of the host species Silene latifolia and S. dioica, using four polymorphic microsatellite loci. In allopatric host populations, the fungus

  14. Host-related genetic differentiation in the anther smut fungus Microbotryum violaceum in sympatric, parapatric and allopatric populations of two host species Silene latifolia and S-dioica

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    Van Putten, WF; Biere, A; Van Damme, JMM

    We investigated genetic diversity in West European populations of the fungal pathogen Microbotryum violaceum in sympatric, parapatric and allopatric populations of the host species Silene latifolia and S. dioica, using four polymorphic microsatellite loci. In allopatric host populations, the fungus

  15. Silene noctiflora L., present in the flora of Kosovo and Metohija (Serbia

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    Prodanović, D.

    2016-12-01

    Full Text Available The genus Silene (family Caryophyllaceae comprises more than 700 species and it is one of the larger genera of the World’s flora. Studying the flora of the plain part of Kosovo and Metohija, in the village of Gračanica, on the eastern rim of the Kosovo basin (approximately 10 km to the south of Priština, near the Gračanka stream, we identified a weed and ruderal species, Silene noctiflora. The part of the stream bank is urbanised and turned into a quay. The quay is regularly maintained implying that the banks are regularly weeded and the riverbeds are cleaned as the Typha latifolia species rapidly grows; it may be the reason why this species was not immediately detected and appropriately identified. Except for the afore mentioned locality, the species was also reported on the neglected arable fields and tilths, around the unkempt orchards, along the new tarmac road between Gračanica and Laplje Selo, on the locality called Labura. Silene noctiflora is not mentioned for the region of Kosovo and Metohija in the new and revised edition of the book Flora of Serbia 2.

  16. Night life on the beach: selfing to avoid pollinator competition between two sympatric Silene species.

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    Buide, M Luisa; del Valle, José Carlos; Pissatto, Mônica; Narbona, Eduardo

    2015-08-01

    Evolution of autonomous selfing may be advantageous because it allows for reproductive assurance. In co-flowering plants competing for pollinators, the least common and/or attractive could suffer pollen limitations. Silene niceensis and S. ramosissima are taxonomically related species sharing the same habitat, although S. ramosissima is less abundant and has a more restricted distribution. They also have the same a priori nocturnal pollinator syndrome, and show an overlapping flowering phenology. The aim of this study was to investigate whether a selfing strategy in S. ramosissima allows it to avoid pollinator competition and/or interspecific pollen transfer with S. niceensis, which would thus enable both species to reach high levels of fruit and seed set. The breeding system, petal colour, flower life span and degree of overlap between male and female phases, floral visitor abundance and visitation rates were analysed in two sympatric populations of S. niceensis and S. ramosissima in southern Spain. Autonomous selfing in S. ramosissima produced very high fruit and seed set, which was also similar to open-pollinated plants. Silene niceensis showed minimum levels of autonomous selfing, and pollen/ovule ratios were within the range expected for the breeding system. In contrast to S. niceensis, flower life span was much shorter in S. ramosissima, and male and female organs completely overlapped in space and time. Upper surface petals of both species showed differing brightness, chroma and hue. Flowers of S. niceensis were actively visited by moths, hawkmoths and syrphids, whereas those of S. ramosissima were almost never visited. The findings show that different breeding strategies exist between the sympatric co-flowering S. niceensis and S. ramosissima, the former specializing in crepuscular-nocturnal pollination and the latter mainly based on autonomous selfing. These two strategies allow both species to share the restricted dune habitat in which they exist, with a

  17. A new species of Dianthus (Caryophyllaceae) from Antalya, South Anatolia, Turkey

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    Deniz,İsmail Gökhan; Aykurt,Candan; Genç,İlker; Aksoy,Ahmet

    2016-01-01

    Abstract Dianthus multiflorus from Gazipa?a (Antalya), south Anatolia (Turkey), is described as a new annual species with verrucose calyx. The morphological differences from the species within the same group with Dianthus multiflorus , which are Dianthus aydogdui , Dianthus cyri and Dianthus tripunctatus , are discussed. The International Union for Conservation of Nature (IUCN) threat category and observations on the ecology of the populations are noted. The karyology and seed micromorphology...

  18. A new species of Dianthus (Caryophyllaceae) from Antalya, South Anatolia, Turkey.

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    Deniz, İsmail Gökhan; Aykurt, Candan; Genç, İlker; Aksoy, Ahmet

    2016-01-01

    Dianthus multiflorus from Gazipaşa (Antalya), south Anatolia (Turkey), is described as a new annual species with verrucose calyx. The morphological differences from the species within the same group with Dianthus multiflorus, which are Dianthus aydogdui, Dianthus cyri and Dianthus tripunctatus, are discussed. The International Union for Conservation of Nature (IUCN) threat category and observations on the ecology of the populations are noted. The karyology and seed micromorphology of Dianthus multiflorus and Dianthus tripunctatus were examined by light microscopy and scanning electron microscopy.

  19. Apoptotic potential of two Caryophyllaceae species in MCF-7 and MDA-MB-468 cell lines

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    M. Mosaddegh

    2018-01-01

    Full Text Available Background and objectives: Plants have been used to treat diseases like cancer for many years and today the trend towards their use is increasing. One of the most effective mechanisms of plants against cancer is inducing apoptosis. Apoptosis is a programmed cell death which acts opposite to cell division. It starts in response to some stimuli. Despite the effectiveness of apoptosis inducing agents, their use has been limited due to side effects and resistance to these treatments; so, applying medicinal herbs due to their lower cost and toxicity has drawn attentions. Recent research at the Traditional Medicine and Materia Medica Research Center, Shahid Beheshti University of Medical Sciences on two medicinal plants Acanthophyllum bracteatum and A. microcephalum has shown cytotoxic effects of these two species, but the mechanism of their toxicity has remained unknown; thus, the present study was designed to evaluate the apoptotic potential of Acanthophyllum bracteatum and A. microcephalum. Methods: In the present study, the cytotoxic effects of the methanol extract of Acanthophyllum bracteatum and A. microcephalum was evaluated against MCF-7 and MDA-MB-468 cells by MTT assay; furthermore, their apoptosis potential has been evaluated by annexin-V/propidium iodide assay and Hoechst 33258 staining in the same cell lines. Results: The methanol extract of A. microcephalum and A. bracteatum showed cytotoxic effects against MCF-7 and MDA-MB-468 cell lines with IC50 values of 64, 159 and 102, 250 μg/mL, respectively. The results of the apoptosis assays confirmed the potential of the two plants extracts to induce apoptosis in both cell lines while A. microcephalum demonstrated more considerable results. Conclusion: A. microcephalum could be a suitable choice for further breast cancer studies.

  20. Nectar sugar composition of European Caryophylloideae (Caryophyllaceae) in relation to flower length, pollination biology and phylogeny.

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    Witt, T; Jürgens, A; Gottsberger, G

    2013-10-01

    Floral nectar composition has been explained as an adaptation to factors that are either directly or indirectly related to pollinator attraction. However, it is often unclear whether the sugar composition is a direct adaptation to pollinator preferences. Firstly, the lower osmolality of sucrose solutions means that they evaporate more rapidly than hexose solutions, which might be one reason why sucrose-rich nectar is typically found in flowers with long tubes (adapted to long-tongued pollinators), where it is better protected from evaporation than in open or short-tubed flowers. Secondly, it can be assumed that temperature-dependent evaporation is generally lower during the night than during the day so that selection pressure to secrete nectar with high osmolality (i.e. hexose-rich solutions) is relaxed for night-active flowers pollinated at night. Thirdly, the breeding system may affect selection pressure on nectar traits; that is, for pollinator-independent, self-pollinated plants, a lower selective pressure on nectar traits can be assumed, leading to a higher variability of nectar sugar composition independent of pollinator preferences, nectar accessibility and nectar protection. To analyse the relations between flower tube length, day vs. night pollination and self-pollination, the nectar sugar composition was investigated in 78 European Caryophylloideae (Caryophyllaceae) with different pollination modes (diurnal, nocturnal, self-pollination) using high-performance liquid chromatography (HPLC). All Caryophylleae species (Dianthus and relatives) were found to have nectar with more than 50% sucrose, whereas the sugar composition of Sileneae species (Silene and relatives) ranged from 0% to 98.2%. In the genus Silene, a clear dichotomous distribution of sucrose- and hexose-dominant nectars is evident. We found a positive correlation between the flower tube length and sucrose content in Caryophylloideae, particularly in day-flowering species, using both conventional

  1. The alpine cushion plant Silene acaulis as foundation species: a bug's-eye view to facilitation and microclimate.

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    Olivia Molenda

    Full Text Available Alpine ecosystems are important globally with high levels of endemic and rare species. Given that they will be highly impacted by climate change, understanding biotic factors that maintain diversity is critical. Silene acaulis is a common alpine nurse plant shown to positively influence the diversity and abundance of organisms--predominantly other plant species. The hypothesis that cushion or nurse plants in general are important to multiple trophic levels has been proposed but rarely tested. Alpine arthropod diversity is also largely understudied worldwide, and the plant-arthropod interactions reported are mostly negative, that is,. herbivory. Plant and arthropod diversity and abundance were sampled on S. acaulis and at paired adjacent microsites with other non-cushion forming vegetation present on Whistler Mountain, B.C., Canada to examine the relative trophic effects of cushion plants. Plant species richness and abundance but not Simpson's diversity index was higher on cushion microsites relative to other vegetation. Arthropod richness, abundance, and diversity were all higher on cushion microsites relative to other vegetated sites. On a microclimatic scale, S. acaulis ameliorated stressful conditions for plants and invertebrates living inside it, but the highest levels of arthropod diversity were observed on cushions with tall plant growth. Hence, alpine cushion plants can be foundation species not only for other plant species but other trophic levels, and these impacts are expressed through both direct and indirect effects associated with altered environmental conditions and localized productivity. Whilst this case study tests a limited subset of the membership of alpine animal communities, it clearly demonstrates that cushion-forming plant species are an important consideration in understanding resilience to global changes for many organisms in addition to other plants.

  2. Improving niche projections of plant species under climate change: Silene acaulis on the British Isles as a case study

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    Ferrarini, Alessandro; Alsafran, Mohammed H. S. A.; Dai, Junhu; Alatalo, Juha M.

    2018-04-01

    Empirical works to assist in choosing climatically relevant variables in the attempt to predict climate change impacts on plant species are limited. Further uncertainties arise in choice of an appropriate niche model. In this study we devised and tested a sharp methodological framework, based on stringent variable ranking and filtering and flexible model selection, to minimize uncertainty in both niche modelling and successive projection of plant species distributions. We used our approach to develop an accurate, parsimonious model of Silene acaulis (L.) presence/absence on the British Isles and to project its presence/absence under climate change. The approach suggests the importance of (a) defining a reduced set of climate variables, actually relevant to species presence/absence, from an extensive list of climate predictors, and (b) considering climate extremes instead of, or together with, climate averages in projections of plant species presence/absence under future climate scenarios. Our methodological approach reduced the number of relevant climate predictors by 95.23% (from 84 to only 4), while simultaneously achieving high cross-validated accuracy (97.84%) confirming enhanced model performance. Projections produced under different climate scenarios suggest that S. acaulis will likely face climate-driven fast decline in suitable areas on the British Isles, and that upward and northward shifts to occupy new climatically suitable areas are improbable in the future. Our results also imply that conservation measures for S. acaulis based upon assisted colonization are unlikely to succeed on the British Isles due to the absence of climatically suitable habitat, so different conservation actions (seed banks and/or botanical gardens) are needed.

  3. Caryophyllaceae endémicas del Perú

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    Asunción Cano

    2013-10-01

    Full Text Available The Caryophyllaceae are represented in Peru by 19 genera and 126 species (Brako & Zarucchi, 1993, mainly herbs and subshrubs. Here we recognize 44 endemic taxa in 11 genera. We applied IUCN categories and criteria to 43 taxa. Endemic taxa are found mainly in the High- Andean and Mesoandean regions, between 2500 and 4950 m elevation. Ten endemic species have been registered within Peru´s protected areas system.

  4. Genomic diversity in two related plant species with and without sex chromosomes - Silene latifolia and S. vulgaris

    Czech Academy of Sciences Publication Activity Database

    Čegan, Radim; Vyskot, Boris; Kejnovský, Eduard; Kubát, Zdeněk; Blavet, Hana; Šafář, Jan; Doležel, Jaroslav; Blavet, N.; Hobza, Roman

    2012-01-01

    Roč. 7, č. 2 (2012), e31898 E-ISSN 1932-6203 R&D Projects: GA AV ČR(CZ) KJB600040901; GA ČR(CZ) GPP501/10/P483; GA ČR(CZ) GAP501/10/0102; GA ČR(CZ) GD204/09/H002; GA ČR(CZ) GAP305/10/0930; GA ČR(CZ) GA522/09/0083 Institutional research plan: CEZ:AV0Z50040702; CEZ:AV0Z50040507; CEZ:AV0Z50380511 Keywords : Silene * repetitive DNA * genome size Subject RIV: BO - Biophysics Impact factor: 3.730, year: 2012

  5. The composition and depth of green roof substrates affect the growth of Silene vulgaris and Lagurus ovatus species and the C and N sequestration under two irrigation conditions.

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    Ondoño, S; Martínez-Sánchez, J J; Moreno, J L

    2016-01-15

    Extensive green roofs are used to increase the surface area covered by vegetation in big cities, thereby reducing the urban heat-island effect, promoting CO2 sequestration, and increasing biodiversity and urban-wildlife habitats. In Mediterranean semi-arid regions, the deficiency of water necessitates the use in these roofs of overall native plants which are more adapted to drought than other species. However, such endemic plants have been used scarcely in green roofs. For this purpose, we tested two different substrates with two depths (5 and 10 cm), in order to study their suitability with regard to adequate plant development under Mediterranean conditions. A compost-soil-bricks (CSB) (1:1:3; v:v:v) mixture and another made up of compost and bricks (CB) (1:4; v:v) were arranged in two depths (5 and 10 cm), in cultivation tables. Silene vulgaris (Moench) Garcke and Lagurus ovatus L. seeds were sown in each substrate. These experimental units were subjected, on the one hand, to irrigation at 40% of the registered evapotranspiration values (ET0) and, on the other, to drought conditions, during a nine-month trial. Physichochemical and microbiological substrate characteristics were studied, along with the physiological and nutritional status of the plants. We obtained significantly greater plant coverage in CSB at 10 cm, especially for L. ovatus (80-90%), as well as a better physiological status, especially in S. vulgaris (SPAD values of 50-60), under irrigation, whereas neither species could grow in the absence of water. The carbon and nitrogen fixation by the substrate and the aboveground biomass were also higher in CSB at 10 cm, especially under L. ovatus - in which 1.32 kg C m(-2) and 209 g N m(-2) were fixed throughout the experiment. Besides, the enzymatic and biochemical parameters assayed showed that microbial activity and nutrient cycling, which fulfill a key role for plant development, were higher in CSB. Therefore, irrigation of 40% can

  6. Status and limiting factors of two rare plant species in dry montane communities of Hawai`i Volcanoes National Park.

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    Pratt, Linda W.; VanDeMark, Joshua R.; Euaparadorn, Melody

    2012-01-01

    Two rare plants native to montane dry forests and woodland communities of Hawai`i Volcanoes National Park (HAVO) were studied for more than two years to determine their stand structure, short-term mortality rates, patterns of reproductive phenology, success of fruit production, floral visitor composition, seed germination rates in the greenhouse, and survival of both natural and planted seedlings. Phyllostegia stachyoides, a shrubby Hawaiian mint (Lamiaceae) that is a species of concern, was studied within two small kīpuka at a natural population on the park’s Mauna Loa Strip, and three plantings at sites along the Mauna Loa Road were also monitored. Silene hawaiiensis, a threatened shrub species in the pink family (Caryophyllaceae), was monitored at two natural populations, one on Mauna Loa at the Three Trees Kīpuka and the second on Kīlauea Crater Rim south of Halema`uma`u. Silene hawaiiensis plantings were also made inside and outside ungulate exclosures at the park’s Kahuku Unit

  7. Orobanche caryophyllacea Sm. (Orobanchaceae in Poland: current distribution, taxonomy, plant communities and hosts

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    Renata Piwowarczyk

    2014-09-01

    Full Text Available The paper presents the current distribution of Orobanche caryophyllacea Sm. in Poland based on a critical revision of herbarium and literature data as well as the results of my field studies. The majority of localities are in south and south-eastern Poland: Małopolska Upland, Lublin Upland, Roztocze, Przemyśl Foothills, Pieniny Mts, rarely in the valleys of the Lower Vistula and Oder rivers or Wolin island. The distribution map in Poland is included. The taxonomy, biology and ecology of the species are discussed.

  8. Medicinal plants of the family Caryophyllaceae: a review of ethno-medicinal uses and pharmacological properties

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    Satish Chandra

    2015-09-01

    Full Text Available Several species of the family Caryophyllaceae are widely used by many ethnic communities as traditional medicine throughout the world. The highest number of plants of the family are used in Chinese traditional medicine. The ethnopharmacologial studies of this family indicate that plants of the family possess anticancer, antibacterial, antifungal, antiviral, antioxidant, and anti-inflammatory properties. Other miscellaneous properties reported are ribosome inactivation properties, inhibition of prostatic enlargement in rats, and inhibition of intestinal enzyme carboxyelasterase in rats, cerebro-protective activity, and antiobesity in rats. Few reviews have been published yet, providing information regarding medicinal plants of the family and their biomedical properties. All published reviews have focused either on a particular taxa or a few species. The present review is focused on the traditional medicinal uses of the plants of the family Caryophyllaceae along with phytochemical and pharmacological studies of the family. A study of the literature revealed significant traditional medicinal importance of the family. Major chemical constituents of Caryophyllceae are saponins, Phytoecdysteroids, benzenoids, phenyl propanoids, and nitrogen containing compounds. The most important property of plants of the family is anticancer activity and is shown by the large number of plant species studied. This review of traditional medicinal and pharmacological uses of plants of the family, provide a ground for future research in the family.

  9. Pollinator specialization and pollination syndromes of three related North American Silene.

    Science.gov (United States)

    Reynolds, Richard J; Westbrook, M Jody; Rohde, Alexandra S; Cridland, Julie M; Fenster, Charles B; Dudash, Michele R

    2009-08-01

    Community and biogeographic surveys often conclude that plant-pollinator interactions are highly generalized. Thus, a central implication of the pollination syndrome concept, that floral trait evolution occurs primarily via specialized interactions of plants with their pollinators, has been questioned. However, broad surveys may not distinguish whether flower visitors are actual pollen vectors and hence lack power to assess the relationship between syndrome traits and the pollinators responsible for their evolution. Here we address whether the floral traits of three closely related hermaphroditic Silene spp. native to eastern North America (S. caroliniana, S. virginica, and S. stellata) correspond to predicted specialized pollination based on floral differences among the three species and the congruence of these floral features with recognized pollination syndromes. A nocturnal/diurnal pollinator exclusion experiment demonstrated that all three Silene spp. have diurnal pollinators, and only S. stellata has nocturnal pollinators. Multiyear studies of visitation rates demonstrated that large bees, hummingbirds, and nocturnal moths were the most frequent pollinators of S. caroliniana, S. virginica, and S. stellata, respectively. Estimates of pollen grains deposited and removed per visit generally corroborated the visitation rate results for all three species. However, the relatively infrequent diurnal hawkmoth pollinators of S. caroliniana were equally effective and more efficient than the most frequent large bee visitors. Pollinator importance (visitation X deposition) of each of the animal visitors to each species was estimated and demonstrated that in most years large bees and nocturnal moths were the most important pollinators of S. caroliniana and S. stellata, respectively. By quantifying comprehensive aspects of the pollination process we determined that S. virginica and S. stellata were specialized on hummingbirds and nocturnal moths, respectively, and S

  10. A new species of Stellaria (Caryophyllaceae) from the Nepal Himalaya

    NARCIS (Netherlands)

    Majumdar, N.C.

    1968-01-01

    Herba perennis, gracilis, caule repente valde furcato. Rami erecti vel suberecti, quadrangulares, e gemmis axillaribus emergentes, straminei, squamosi, simpliccs et infra glabrescentes, corymbose furcati et glandulari-pubescentes, sursum altitudine 10—20 cm attingentes. Folia simplicia, exstipulata,

  11. Coping with third parties in a nursery pollination mutualism: Hadena bicruris avoids oviposition on pathogen-infected, less rewarding Silene latifolia

    NARCIS (Netherlands)

    Biere, A.; Honders, S.C.

    2006-01-01

    In nursery pollination systems, pollinator offspring usually feed on pollinated fruits or seeds. Costs and benefits of the interaction for plant and pollinator, and hence its local outcome (antagonismmutualism), can be affected by the presence of 'third-party' species. Infection of Silene latifolia

  12. Intraspecific competition and mating between fungal strains of the anther smut Microbotryum violaceum from the host plants Silene latifolia and S-dioica.

    NARCIS (Netherlands)

    Van Putten, W.F.; Biere, A.; Van Damme, J.M.M.

    2003-01-01

    We studied intraspecific competition and assortative mating between strains of the anther smut fungus Microbotryum violaceum from two of its host species, Silene latifolia and S. dioica. Specifically, we investigated whether strains from allopatric host populations have higher competitive ability on

  13. Intraspecific competition and mating between fungal strains of the anther smut Microbotryum violaceum from the host plants Silene latifolia and S-dioica

    NARCIS (Netherlands)

    Van Putten, WF; Biere, A; Van Damme, JMM

    We studied intraspecific competition and assortative mating between strains of the anther smut fungus Microbotryum violaceum from two of its host species, Silene latifolia and S. dioica. Specifically. we investigated whether strains from allopatric host populations have higher competitive ability on

  14. Ecological implications of reduced pollen deposition in alpine plants: a case study using a dominant cushion plant species.

    Science.gov (United States)

    Reid, Anya; Hooper, Robyn; Molenda, Olivia; Lortie, Christopher J

    2014-01-01

    The reproductive assurance hypothesis states that self-incompatible female plants must produce twice the number of seeds relative to their self-compatible hermaphroditic counterparts to persist in gynodioecious populations. This is a viable life-history strategy, provided that pollination rates are sufficiently high. However, reduced pollination rates in alpine plants are likely due to climate induced plant-pollinator mismatches and general declines in pollinators. Using a gynodioecious population of the dominant plant Silene acaulis (Caryophyllaceae), we tested the reproductive assurance hypothesis and also the stress gradient hypothesis with a series of pollinator exclusion trials and extensive measurements of subsequent reproductive output (gender ratio, plant size, percent fruit-set, fruit weight, seeds per fruit, total seeds, seed weight, and seed germination). The reproductive assurance hypothesis was supported with female plants being more sensitive to and less likely to be viable under reductions in pollination rates. These findings are the first to show that the stress gradient hypothesis is also supported under a gradient of pollen supply instead of environmental limitations. Beneficiary abundance was negatively correlated to percent fruit-set under current pollen supply, but became positive under reduced pollen supply suggesting that there are important plant-plant-pollinator interactions related to reproduction in these alpine plant species.

  15. Comparative high-throughput transcriptome sequencing and development of SiESTa, the Silene EST annotation database

    Directory of Open Access Journals (Sweden)

    Marais Gabriel AB

    2011-07-01

    Full Text Available Abstract Background The genus Silene is widely used as a model system for addressing ecological and evolutionary questions in plants, but advances in using the genus as a model system are impeded by the lack of available resources for studying its genome. Massively parallel sequencing cDNA has recently developed into an efficient method for characterizing the transcriptomes of non-model organisms, generating massive amounts of data that enable the study of multiple species in a comparative framework. The sequences generated provide an excellent resource for identifying expressed genes, characterizing functional variation and developing molecular markers, thereby laying the foundations for future studies on gene sequence and gene expression divergence. Here, we report the results of a comparative transcriptome sequencing study of eight individuals representing four Silene and one Dianthus species as outgroup. All sequences and annotations have been deposited in a newly developed and publicly available database called SiESTa, the Silene EST annotation database. Results A total of 1,041,122 EST reads were generated in two runs on a Roche GS-FLX 454 pyrosequencing platform. EST reads were analyzed separately for all eight individuals sequenced and were assembled into contigs using TGICL. These were annotated with results from BLASTX searches and Gene Ontology (GO terms, and thousands of single-nucleotide polymorphisms (SNPs were characterized. Unassembled reads were kept as singletons and together with the contigs contributed to the unigenes characterized in each individual. The high quality of unigenes is evidenced by the proportion (49% that have significant hits in similarity searches with the A. thaliana proteome. The SiESTa database is accessible at http://www.siesta.ethz.ch. Conclusion The sequence collections established in the present study provide an important genomic resource for four Silene and one Dianthus species and will help to

  16. Comparative high-throughput transcriptome sequencing and development of SiESTa, the Silene EST annotation database

    Science.gov (United States)

    2011-01-01

    Background The genus Silene is widely used as a model system for addressing ecological and evolutionary questions in plants, but advances in using the genus as a model system are impeded by the lack of available resources for studying its genome. Massively parallel sequencing cDNA has recently developed into an efficient method for characterizing the transcriptomes of non-model organisms, generating massive amounts of data that enable the study of multiple species in a comparative framework. The sequences generated provide an excellent resource for identifying expressed genes, characterizing functional variation and developing molecular markers, thereby laying the foundations for future studies on gene sequence and gene expression divergence. Here, we report the results of a comparative transcriptome sequencing study of eight individuals representing four Silene and one Dianthus species as outgroup. All sequences and annotations have been deposited in a newly developed and publicly available database called SiESTa, the Silene EST annotation database. Results A total of 1,041,122 EST reads were generated in two runs on a Roche GS-FLX 454 pyrosequencing platform. EST reads were analyzed separately for all eight individuals sequenced and were assembled into contigs using TGICL. These were annotated with results from BLASTX searches and Gene Ontology (GO) terms, and thousands of single-nucleotide polymorphisms (SNPs) were characterized. Unassembled reads were kept as singletons and together with the contigs contributed to the unigenes characterized in each individual. The high quality of unigenes is evidenced by the proportion (49%) that have significant hits in similarity searches with the A. thaliana proteome. The SiESTa database is accessible at http://www.siesta.ethz.ch. Conclusion The sequence collections established in the present study provide an important genomic resource for four Silene and one Dianthus species and will help to further develop Silene as a

  17. De novo transcriptome assembly of heavy metal tolerant Silene dioica

    Czech Academy of Sciences Publication Activity Database

    Čegan, R.; Hudzieczek, V.; Hobza, Roman

    2017-01-01

    Roč. 11, MAR (2017), s. 118-119 ISSN 2213-5960 Institutional support: RVO:61389030 Keywords : genome * Silene dioica * RNA-Seq * Transcriptome * Heavy metal tolerance * Sex chromosomes Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany

  18. Comparative study of autecological, morphological, anatomical and karyological characteristics of Acanthophyllum ejtehadii Mahmoudi & Vaezi (Caryophyllaceae: a rare endemic in Iran

    Directory of Open Access Journals (Sweden)

    Zahra Maleki Sadabadi

    2017-08-01

    Full Text Available Characterizing traits of a species in its habitat is substantial for planning a practical conservation program. Acanthophyllum ejtehadii Mahmoudi & Vaezi (Caryophyllaceae is a recently established endemic species for flora of Iran and has a narrow non-conserved natural habitat in Radkan region of Chenaran, Razavi Khorasan Province. The soil and climate of Radkan was studied and the ecological, morphological, anatomical, and karyological aspects of A. ejtehadii were investigated to obtain a comprehensive knowledge about this species and its natural growth conditions. Field observations were performed during the growing seasons in 2014‒2015 and 29 vegetation samples were collected as data. Results showed that this plant grows in mound-like sites on clay-loam soils at mean elevation 1279 m.a.s.l. in arid climate. Acanthophyllum ejtehadii is a thorn-cushion form chamaephyte plant. This Plant grow gradually in early-January, the flower unfolds in early-June and the matured seeds are produced in mid-July. A. ejtehadii is a diploid (2n=2x =30 species and has homogenous karyotype. Having unique morphological and anatomical adaptations such as expanded surface roots, reduced leaf area and thickened cuticle, this plant grows successfully in harsh environments. These mechanisms are specific to this specific kind of Acanthophyllum species. The Speciation time of this plant was estimated not more than 200 thousand years ago and if Radkan is preserved from anthropogenic disturbance, this species could expand its distribution area.

  19. On the distribution of Cerastium smolikanum (Caryophyllaceae) and Centaurea vlachorum (Asteraceae) in the Balkan Peninsula

    DEFF Research Database (Denmark)

    Shuka, Lulezim; Tan, Kit

    2009-01-01

    Cerastium smolikanum (Caryophyllaceae) and Centaurea vlachorum (Asteraceae) are reported for the first () and () are reported for the first time in C and NE Albania. These two taxa were previously considered serpentine endemics restricted to a few localities in NW Greece and the extension...

  20. Ecological implications of reduced pollen supply in the alpine: a case study using a dominant cushion plant species [v2; ref status: indexed, http://f1000r.es/3xc

    Directory of Open Access Journals (Sweden)

    Anya Reid

    2014-08-01

    Full Text Available The reproductive assurance hypothesis states that self-incompatible female plants must produce twice the number of seeds relative to their self-compatible hermaphroditic counterparts to persist in gynodioecious populations. This is a viable life-history strategy, provided that pollination rates are sufficiently high. However, reduced pollination rates in alpine plants are likely due to climate induced plant-pollinator mismatches and general declines in pollinators. Using a gynodioecious population of the dominant plant Silene acaulis (Caryophyllaceae, we tested the reproductive assurance hypothesis and also the stress gradient hypothesis with a series of pollinator exclusion trials and extensive measurements of subsequent reproductive output (gender ratio, plant size, percent fruit-set, fruit weight, seeds per fruit, total seeds, seed weight, and seed germination. The reproductive assurance hypothesis was supported with female plants being more sensitive to and less likely to be viable under reductions in pollination rates. These findings are the first to show that the stress gradient hypothesis is also supported under a gradient of pollen supply instead of environmental limitations. Beneficiary abundance was negatively correlated to percent fruit-set under current pollen supply, but became positive under reduced pollen supply suggesting that there are important plant-plant-pollinator interactions related to reproduction in these alpine plant species.

  1. POLLINATOR-MEDIATED COMPETITION, REPRODUCTIVE CHARACTER DISPLACEMENT, AND THE EVOLUTION OF SELFING IN ARENARIA UNIFLORA (CARYOPHYLLACEAE).

    Science.gov (United States)

    Fishman, Lila; Wyatt, Robert

    1999-12-01

    Ecological factors that reduce the effectiveness of cross-pollination are likely to play a role in the frequent evolution of routine self-fertilization in flowering plants. However, we lack empirical evidence linking the reproductive assurance value of selfing in poor pollination environments to evolutionary shifts in mating system. Here, we investigated the adaptive significance of prior selfing in the polymorphic annual plant Arenaria uniflora (Caryophyllaceae), in which selfer populations occur only in areas of range overlap with congener A. glabra. To examine the hypothesis that secondary contact between the two species contributed to the evolution and maintenance of selfing, we used field competition experiments and controlled hand-pollinations to measure the female fitness consequences of pollinator-mediated interspecific interactions. Uniformly high fruit set by selfers in the naturally pollinated field arrays confirmed the reproductive assurance value of selfing, whereas substantial reductions in outcrosser fruit set (15%) and total seed production (20-35%) in the presence of A. glabra demonstrated that pollinator-mediated interactions can provide strong selection for self-pollination. Heterospecific pollen transfer, rather than competition for pollinator service, appears to be the primary mechanism of pollinator-mediated competition in Arenaria. Premating barriers to hybridization between outcrossers and A. glabra are extremely weak. The production of a few inviable hybrid seeds after heterospecific pollination and intermediate seed set after mixed pollinations indicates that A. glabra pollen can usurp A. uniflora ovules. Thus, any visit to A. uniflora by shared pollinators carries a potential female fitness cost. Moreover, patterns of fruit set and seed set in the competition arrays relative to controls were consistent with the receipt of mixed pollen loads, rather than a lack of pollinator visits. Competition through pollen transfer favors preemptive

  2. DRDC Ottawa Participation in the SILENE Accident Dosimetry Intercomparison Exercise. June 10-21, 2002

    National Research Council Canada - National Science Library

    Prud'homme-Lalonde, L

    2002-01-01

    .... The SILENE International Accident Dosimetry Intercomparison Exercise at Valduc, France in June 2002 coincided with DRDC Ottawa work designed to refine its proposed criticality dosimetry system...

  3. Research program and uses of the solution fueled reactor SILENE

    International Nuclear Information System (INIS)

    Barbry, F.; Ratel, R.

    1985-09-01

    Designed and operated by the Nuclear Protection and Safety Institute of the CEA, SILENE is an original small sized reactor fueled with an uranyl nitrate solution. The reactor is capable to operate in three modes: ''Pulse'' operation (high power levels up to 1000 Megawatts during several millisecond), ''Free evolution'' operation (simulation of criticality accident excursions), ''Steady state'' operation in a power range of 0.01 W to 1 kW. The core can be surrounded by appropriate shields (lead, polyethylene) to vary the leakage radiations and the gamma to neutron dose ratio. It's possible to insert in the central cavity of the annular core vessel some capsules, devices or samples to be submitted to very high radiations levels. The research activities are mainly devoted towards nuclear safety studies: the criticality accident studies, and the behavior of oxide fuels under transient conditions. Some examples of tests are presented. As to other applications of the SILENE facility, the main studies now in progress deal with: designing and calibration of Health physics intrumentation, neutron and gamma dosimetry, and, radiobiology. Once the characteristics of radiation field are qualified by calculations and experimental techniques, SILENE will be proposed as a reference source [fr

  4. [Examples of the keeping of drugs during the XVIth, XVIIth and XVIIIth centuries: silenes and drawers].

    Science.gov (United States)

    Fievet, B

    1998-01-01

    Silenes are wooden boxes with colourful paintings for the keeping of drugs and can be found nowadays in three collections in France: Hotel-Dieu in Troyes (Aube), a pharmacy in Bauge (Maine-et-Loire) and St-Roch museum in Issoudun (Indre). Drawers can be related to silenes but they are more ordinary and less attractive.

  5. Fuel solution criticality accident studies with the SILENE reactor: phenomenology, consequences and simulated intervention

    International Nuclear Information System (INIS)

    Barbry, F.

    1984-01-01

    After defining the content and the objectives of criticality accident studies, the SILENE reactor, a means of studying fuel solution criticality accidents, is presented. Information obtained from the CRAC and SILENE experimental programs are then presented; they concern power excursion phenomenology, radiological consequences, and finally guide-lines for current and future programs

  6. Effects of pollination timing and distance on seed production in a dioecious weed Silene latifolia

    Science.gov (United States)

    Anderson, Jay F.; Duddu, Hema S. N.; Shirtliffe, Steven J.; Benaragama, Dilshan; Syrovy, Lena D.; Stanley, Katherine A.; Haile, Teketel A.

    2015-11-01

    Silene latifolia Poir. (white cockle or white campion) is an important invasive weed in North American agriculture. It exhibits dioecy, therefore, both male and female plants are required in order for seed production to occur. However, dioecious species being invasive is not common because of their limitations in pollination and subsequent seed production. The objective of this study is to determine the effect of pollination timing and distance on seed production of Silene latifolia. A series of experiments including pollination exclusion, timing and pollination distance were conducted in 2009 and 2010 at or around Saskatoon, Saskatchewan. For pollination exclusion, exclosures were built around the natural female plants for exclosure, sham-exclosure, and male and female combined treatments. Pollination timing was studied by applying exclosure, non-exclosure, night-exclosure, and day-exclosure treatments to individual female plants. Female plants were transplanted along a linear interval at six different distances from the pollen source to study the effect of pollination distance. S. latifolia was exclusively insect-pollinated and pollination occurred both day and night; however, in one year, pollination occurred mainly at night. Female plants that were in the range of 0-4 m from a compatible pollen source experienced no limitation to pollination. However, when the distance was increased further up to 128 m, pollination levels and subsequent seed production were declined. Moreover, there were differences in seed production between years suggesting that pollination was affected by the environmental conditions during pollination and the crop that white cockle was grown in. These experiments indicate that seed production in S. latifolia is limited by insect-pollination. Although there was pollination limitation for seed production at greater distances from a pollen source, the high fecundity rate (3000-18000 seeds per plant) resulted in a large seed output. Thus, we

  7. Molecular characterisation of four double-flowered mutants of Silene dioica representing four centuries of variation

    Science.gov (United States)

    Ingle, Elizabeth K. S.; Gilmartin, Philip M.

    2015-01-01

    Records of double-flowered Silene dioica date from the late sixteenth century and four named varieties are grown today, as previously, for their horticultural interest. Although double-flowered mutants have been characterized in several plants, their study in dioecious species is of particular interest due to influences of the homeotic mutation on the different floral whorl configurations in males and females. We have analysed four double-flowered varieties of Silene dioica: Flore Pleno and Rosea Plena date back to the seventeenth and nineteenth centuries, Thelma Kay and Firefly were recognized in the latter part of the twentieth and early twenty-first centuries. We have analysed the floral structure of the four varieties, which have distinct floral architectures. Based on Y chromosome-specific PCR analysis we show that Firefly is male and that the other three varieties are female: Random Amplification of Polymorphic DNA (RAPD) analyses suggested a common origin for the three female varieties. The double-flowered phenotype in all four varieties is caused by mutation of the C-function MADS-box transcription factor gene SDM1. We show that Firefly carries a unique 44bp insertion into SDM1, revealing an independent origin for this variety. Comparative analysis of SDM1 cDNA and genomic sequences in Flore Pleno, Rosea Plena and Thelma Kay shows that all three are caused by the same 7bp insertion within SDM1 and therefore share a common origin. The three alleles also differ by several single nucleotide polymorphisms, which represent somatic mutations accumulated over four centuries of asexual propagation. PMID:25878355

  8. On flavonoid accumulation in different plant parts: Variation patterns among individuals and populations in the shore campion (Silene littorea.

    Directory of Open Access Journals (Sweden)

    Jose Carlos Del Valle

    2015-10-01

    Full Text Available The presence of anthocyanins in flowers and fruits is frequently attributed to attracting pollinators and dispersers. In vegetative organs, anthocyanins and other non-pigmented flavonoids such as flavones and flavonols may serve protective functions against UV radiation, cold, heat, drought, salinity, pathogens and herbivores; thus, these compounds are usually produced as a plastic response to such stressors. Although the independent accumulation of anthocyanins in reproductive and vegetative tissues is commonly postulated due to differential regulation, the accumulation of flavonoids within and among populations has never been thoroughly compared. Here, we investigated the shore campion (Silene littorea, Caryophyllaceae which exhibits variation in anthocyanin accumulation in its floral and vegetative tissues. We examined the in-situ accumulation of flavonoids in floral (petals and calyxes and vegetative organs (leaves from 18 populations representing the species’ geographic distribution. Each organ exhibited considerable variability in the content of anthocyanins and other flavonoids both within and among populations. In all organs, anthocyanin and other flavonoids were correlated. At the plant level, the flavonoid content in petals, calyxes and leaves was not correlated in most of the populations. However, at the population level, the mean amount of anthocyanins in all organs was positively correlated, which suggests that the variable environmental conditions of populations may play a role in anthocyanin accumulation. These results are unexpected because the anthocyanins are usually constitutive in petals, yet contingent to environmental conditions in calyxes and leaves. Anthocyanin variation in petals may influence pollinator attraction and subsequent plant reproduction, yet the amount of anthocyanins may be a direct response to environmental factors. In populations on the west coast, a general pattern of increasing accumulation of

  9. The SILENE reactor: an instrument suitable for studying the impact of intermediate and high radiation doses

    International Nuclear Information System (INIS)

    Verray, B.; Leo, Y.; Fouillaud, P.

    2002-01-01

    Designed in 1974 to study the phenomenology and consequences of a criticality accident, the SILENE experimental reactor, an intense source of mixed neutron and gamma radiation, is also suited to radiobiological studies. (author)

  10. Mosaic origins of a complex chimeric mitochondrial gene in Silene vulgaris.

    Directory of Open Access Journals (Sweden)

    Helena Storchova

    Full Text Available Chimeric genes are significant sources of evolutionary innovation that are normally created when portions of two or more protein coding regions fuse to form a new open reading frame. In plant mitochondria astonishingly high numbers of different novel chimeric genes have been reported, where they are generated through processes of rearrangement and recombination. Nonetheless, because most studies do not find or report nucleotide variation within the same chimeric gene, evolution after the origination of these chimeric genes remains unstudied. Here we identify two alleles of a complex chimera in Silene vulgaris that are divergent in nucleotide sequence, genomic position relative to other mitochondrial genes, and expression patterns. Structural patterns suggest a history partially influenced by gene conversion between the chimeric gene and functional copies of subunit 1 of the mitochondrial ATP synthase gene (atp1. We identified small repeat structures within the chimeras that are likely recombination sites allowing generation of the chimera. These results establish the potential for chimeric gene divergence in different plant mitochondrial lineages within the same species. This result contrasts with the absence of diversity within mitochondrial chimeras found in crop species.

  11. Point and interval estimation of pollinator importance: a study using pollination data of Silene caroliniana.

    Science.gov (United States)

    Reynolds, Richard J; Fenster, Charles B

    2008-05-01

    Pollinator importance, the product of visitation rate and pollinator effectiveness, is a descriptive parameter of the ecology and evolution of plant-pollinator interactions. Naturally, sources of its variation should be investigated, but the SE of pollinator importance has never been properly reported. Here, a Monte Carlo simulation study and a result from mathematical statistics on the variance of the product of two random variables are used to estimate the mean and confidence limits of pollinator importance for three visitor species of the wildflower, Silene caroliniana. Both methods provided similar estimates of mean pollinator importance and its interval if the sample size of the visitation and effectiveness datasets were comparatively large. These approaches allowed us to determine that bumblebee importance was significantly greater than clearwing hawkmoth, which was significantly greater than beefly. The methods could be used to statistically quantify temporal and spatial variation in pollinator importance of particular visitor species. The approaches may be extended for estimating the variance of more than two random variables. However, unless the distribution function of the resulting statistic is known, the simulation approach is preferable for calculating the parameter's confidence limits.

  12. Measurement of the gamma field around Silene reactor

    International Nuclear Information System (INIS)

    Spurny, Frantisek; Medioni, Roger.

    1976-07-01

    A method for measuring the gamma component in the mixed field emitted by the Silene facility implanted in Valduc is investigated. Various thermoluminescent phosphors (natural LiF, 7 LiF, SO 4 Ca, Al 2 O 3 ) in containers of different sizes and types are used. The detectors results are corrected for their neutron sensitivity by using coefficients which were determined in previous studies. Alumina is shown to be the most suitable detector for this problem because of the dose ranges to be measured and its low sensitivity to neutrons. A series of measurements carried out at many points in the irradiation hall shows a good homogeneity in the gamma distribution. Results are given for different distances from the source and for a 10 17 fissions power of the reactor [fr

  13. A new physical mapping approach refines the sex-determining gene positions on the Silene latifolia Y-chromosome

    Science.gov (United States)

    Kazama, Yusuke; Ishii, Kotaro; Aonuma, Wataru; Ikeda, Tokihiro; Kawamoto, Hiroki; Koizumi, Ayako; Filatov, Dmitry A.; Chibalina, Margarita; Bergero, Roberta; Charlesworth, Deborah; Abe, Tomoko; Kawano, Shigeyuki

    2016-01-01

    Sex chromosomes are particularly interesting regions of the genome for both molecular genetics and evolutionary studies; yet, for most species, we lack basic information, such as the gene order along the chromosome. Because they lack recombination, Y-linked genes cannot be mapped genetically, leaving physical mapping as the only option for establishing the extent of synteny and homology with the X chromosome. Here, we developed a novel and general method for deletion mapping of non-recombining regions by solving “the travelling salesman problem”, and evaluate its accuracy using simulated datasets. Unlike the existing radiation hybrid approach, this method allows us to combine deletion mutants from different experiments and sources. We applied our method to a set of newly generated deletion mutants in the dioecious plant Silene latifolia and refined the locations of the sex-determining loci on its Y chromosome map.

  14. Transgenerational plasticity in Silene vulgaris in response to three types of stress.

    Science.gov (United States)

    Sandner, T M; van Braak, J L; Matthies, D

    2018-03-23

    The environment experienced by plants can influence the phenotype of their offspring. Such transgenerational plasticity can be adaptive when it results in higher fitness of the offspring under conditions correlated with those experienced by the mother plant. However, it has rarely been tested if such anticipatory parental effects may be induced with different environments. We grew clonal replicates of Silene vulgaris under control conditions and three types of stress (nutrient deficiency, copper addition and drought), which are known from natural populations of the species. We then subjected offspring from differently treated mother plants to each of the different stress treatments to analyse the influence of maternal and offspring environment on performance and several functional traits. Current stress treatments strongly influenced biomass and functional traits of the plants, mostly in line with responses predicted by the theory of functional equilibrium. Plant performance was also influenced by maternal stress treatments, and some effects independent of initial size differences remained until harvest. In particular, stressed mothers produced offspring of higher fitness than control plants. However, there was no evidence for treatment-specific adaptive transgenerational plasticity, as offspring from a mother plant that had grown in a specific environment did not grow better in that environment than other plants. Our results indicate that the maternal environment may affect offspring traits and performance, but also that this transgenerational plasticity is not necessarily adaptive. © 2018 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

  15. Photosynthetic responses to temperature and light of Antarctic and Andean populations of Colobanthus quitensis (Caryophyllaceae) Respuestas fotosintéticas a la temperatura y a la luz de poblaciones antarticas y andinas de Colobanthus quitensis (Caryophyllaceae)

    OpenAIRE

    ÁNGELA SIERRA-ALMEIDA; M. ANGÉLICA CASANOVA-KATNY; LEÓN A BRAVO; LUIS J CORCUERA; LOHENGRIN A CAVIERES

    2007-01-01

    Colobanthus quitensis (Kunth, 1831) Bartling (Caryophyllaceae) is characterized by a wide latitudinal distribution, ranging between the tropical high Andes and the Antarctic Peninsula. Although both habitat types are characterized by cold and freezing temperatures, important microclimatic differences exist during the growing season. Hence, important differences in the response of the photosynthetic apparatus to abiotic factors could be expected between Antarctic and Andean populations of C. q...

  16. Review of the CRAC and SILENE Criticality Accident Studies

    International Nuclear Information System (INIS)

    Barbry, F.; Fouillaud, P.; Grivot, P.; Reverdy, L.

    2009-01-01

    In 1967, the Commissariat et l'Energie Atomique (French Atomic Energy Agency) performed its first research on criticality accidents for the purpose of limiting their impact on people, the environment, and nuclear facilities themselves. A criticality accident is accompanied by intense neutron and gamma emissions and release of radioactive fission products-gases and aerosols-gene rating risk of irradiation and contamination. This work has supplemented earlier work in criticality safety, which concentrated on critical mass measurements and computations. Understanding of the consequences of criticality accidents was limited. Emergency planning was hampered by lack of data. Information became available from pulsed reactor experiments, but the experiments were restricted to the established reactor configurations. The objectives of research performed at the Valduc criticality laboratory, mainly on aqueous fissile media, using the CRAC and SILENE facilities, by multidisciplinary teams of physicists, dosimetry specialists, and radio-biologists, were to model criticality accident physics, estimate irradiation risks and radioactive releases, detect excursions, and organize emergency response. The results of the Valduc experiments have contributed toward improved understanding of criticality accident phenomenology and better evaluation of the risks associated with such accidents. (authors)

  17. Review of the CRAC and SILENE Criticality Accident Studies

    Energy Technology Data Exchange (ETDEWEB)

    Barbry, F.; Fouillaud, P.; Grivot, P.; Reverdy, L. [CEA Valduc, Serv Rech Neutron and Critcite, 21 - Is-sur-Tille (France)

    2009-02-15

    In 1967, the Commissariat et l'Energie Atomique (French Atomic Energy Agency) performed its first research on criticality accidents for the purpose of limiting their impact on people, the environment, and nuclear facilities themselves. A criticality accident is accompanied by intense neutron and gamma emissions and release of radioactive fission products-gases and aerosols-gene rating risk of irradiation and contamination. This work has supplemented earlier work in criticality safety, which concentrated on critical mass measurements and computations. Understanding of the consequences of criticality accidents was limited. Emergency planning was hampered by lack of data. Information became available from pulsed reactor experiments, but the experiments were restricted to the established reactor configurations. The objectives of research performed at the Valduc criticality laboratory, mainly on aqueous fissile media, using the CRAC and SILENE facilities, by multidisciplinary teams of physicists, dosimetry specialists, and radio-biologists, were to model criticality accident physics, estimate irradiation risks and radioactive releases, detect excursions, and organize emergency response. The results of the Valduc experiments have contributed toward improved understanding of criticality accident phenomenology and better evaluation of the risks associated with such accidents. (authors)

  18. Non-coding RNA may be associated with cytoplasmic male sterility in Silene vulgaris

    Czech Academy of Sciences Publication Activity Database

    Stone, James D.; Koloušková, Pavla; Sloan, D.B.; Štorchová, Helena

    2017-01-01

    Roč. 68, č. 7 (2017), s. 1599-1612 ISSN 0022-0957 R&D Projects: GA ČR(CZ) GA16-09220S Institutional support: RVO:61389030 Keywords : Cytoplasmic male sterility * Editing * Mitochondrion * Non-coding RNA * Silene vulgaris * Splicing * Transcriptome Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 5.830, year: 2016

  19. Salicylic Acid Alleviates the Adverse Effects of Salt Stress on Dianthus superbus (Caryophyllaceae) by Activating Photosynthesis, Protecting Morphological Structure, and Enhancing the Antioxidant System

    Science.gov (United States)

    Ma, Xiaohua; Zheng, Jian; Zhang, Xule; Hu, Qingdi; Qian, Renjuan

    2017-01-01

    Salt stress critically affects the physiological processes and morphological structure of plants, resulting in reduced plant growth. Salicylic acid (SA) is an important signal molecule that mitigates the adverse effects of salt stress on plants. Large pink Dianthus superbus L. (Caryophyllaceae) usually exhibit salt-tolerant traits under natural conditions. To further clarify the salt-tolerance level of D. superbus and the regulating mechanism of exogenous SA on the growth of D. superbus under different salt stresses, we conducted a pot experiment to examine the biomass, photosynthetic parameters, stomatal structure, chloroplast ultrastructure, reactive oxygen species (ROS) concentrations, and antioxidant activities of D. superbus young shoots under 0.3, 0.6, and 0.9% NaCl conditions, with and without 0.5 mM SA. D. superbus exhibited reduced growth rate, decreased net photosynthetic rate (Pn), increased relative electric conductivity (REC) and malondialdehyde (MDA) contents, and poorly developed stomata and chloroplasts under 0.6 and 0.9% salt stress. However, exogenously SA effectively improved the growth, photosynthesis, antioxidant enzyme activity, and stoma and chloroplast development of D. superbus. However, when the plants were grown under severe salt stress (0.9% NaCl condition), there was no significant difference in the plant growth and physiological responses between SA-treated and non-SA-treated plants. Therefore, our research suggests that exogenous SA can effectively counteract the adverse effect of moderate salt stress on D. superbus growth and development. PMID:28484476

  20. Salicylic Acid Alleviates the Adverse Effects of Salt Stress on Dianthus superbus (Caryophyllaceae by Activating Photosynthesis, Protecting Morphological Structure, and Enhancing the Antioxidant System

    Directory of Open Access Journals (Sweden)

    Xiaohua Ma

    2017-04-01

    Full Text Available Salt stress critically affects the physiological processes and morphological structure of plants, resulting in reduced plant growth. Salicylic acid (SA is an important signal molecule that mitigates the adverse effects of salt stress on plants. Large pink Dianthus superbus L. (Caryophyllaceae usually exhibit salt-tolerant traits under natural conditions. To further clarify the salt-tolerance level of D. superbus and the regulating mechanism of exogenous SA on the growth of D. superbus under different salt stresses, we conducted a pot experiment to examine the biomass, photosynthetic parameters, stomatal structure, chloroplast ultrastructure, reactive oxygen species (ROS concentrations, and antioxidant activities of D. superbus young shoots under 0.3, 0.6, and 0.9% NaCl conditions, with and without 0.5 mM SA. D. superbus exhibited reduced growth rate, decreased net photosynthetic rate (Pn, increased relative electric conductivity (REC and malondialdehyde (MDA contents, and poorly developed stomata and chloroplasts under 0.6 and 0.9% salt stress. However, exogenously SA effectively improved the growth, photosynthesis, antioxidant enzyme activity, and stoma and chloroplast development of D. superbus. However, when the plants were grown under severe salt stress (0.9% NaCl condition, there was no significant difference in the plant growth and physiological responses between SA-treated and non-SA-treated plants. Therefore, our research suggests that exogenous SA can effectively counteract the adverse effect of moderate salt stress on D. superbus growth and development.

  1. Toxicity Profile of the Aqueous Ethanol Root Extract of Corrigiola telephiifolia Pourr. (Caryophyllaceae in Rodents

    Directory of Open Access Journals (Sweden)

    Hind Lakmichi

    2011-01-01

    Full Text Available Corrigiola telephiifolia Pourr. (Caryophyllaceae is a Moroccan medicinal plant. Despite its popular usage, no study has been published concerning its toxicological profile. The acute toxicity of C. telephiifolia root extract was evaluated by giving it orally to mice at single doses of 5000, 10000, and 14000 mg/kg bodyweight. The extract was also administered at doses of 5, 70, and 2000 mg/kg bodyweight per day to rats for a forty-day toxicity study. No mortality or signs of toxicity were observed in the acute study. In the forty-day study in rats, the extract at 5 mg/kg/day showed no toxicological effects in either sex. At 70 mg/kg/day, the treated group differed from the control only by a significant decrease in serum concentrations of sodium and chloride ions (P<.05. At the dose of 2000 mg/kg/day, the extract significantly increased the serum concentrations of creatinine, alkaline phosphatase, gamma-glutamyltransferase and phosphorus (P<.05 all suggestive of functional nephrotoxicity and hepatotoxicity. The relative bodyweight of both sexes decreased at the dose of 2000 mg/kg/day, with a fast recovery for males. Histological examination did not reveal any treatment-related effects. In conclusion, Corrigiola extract appears safe at the doses used ethno-medicinally. Much higher doses pose toxicological risks.

  2. Transcription profiles of mitochondrial genes correlate with mitochondrial DNA haplotypes in a natural population of Silene vulgaris

    Directory of Open Access Journals (Sweden)

    Olson Matthew S

    2010-01-01

    Full Text Available Abstract Background Although rapid changes in copy number and gene order are common within plant mitochondrial genomes, associated patterns of gene transcription are underinvestigated. Previous studies have shown that the gynodioecious plant species Silene vulgaris exhibits high mitochondrial diversity and occasional paternal inheritance of mitochondrial markers. Here we address whether variation in DNA molecular markers is correlated with variation in transcription of mitochondrial genes in S. vulgaris collected from natural populations. Results We analyzed RFLP variation in two mitochondrial genes, cox1 and atp1, in offspring of ten plants from a natural population of S. vulgaris in Central Europe. We also investigated transcription profiles of the atp1 and cox1 genes. Most DNA haplotypes and transcription profiles were maternally inherited; for these, transcription profiles were associated with specific mitochondrial DNA haplotypes. One individual exhibited a pattern consistent with paternal inheritance of mitochondrial DNA; this individual exhibited a transcription profile suggestive of paternal but inconsistent with maternal inheritance. We found no associations between gender and transcript profiles. Conclusions Specific transcription profiles of mitochondrial genes were associated with specific mitochondrial DNA haplotypes in a natural population of a gynodioecious species S. vulgaris. Our findings suggest the potential for a causal association between rearrangements in the plant mt genome and transcription product variation.

  3. Analytical evaluation of dose measurement of critical accident at SILENE (Contract research)

    CERN Document Server

    Nakamura, T; Tonoike, K

    2003-01-01

    Institute for Radioprotection and Nuclear Safety (IRSN) and the OECD Nuclear Energy Agency (NEA) jointly organized SILENE Accident Dosimetry Intercomparison Exercise to intercompare the dose measurement systems of participating countries. Each participating country carried out dose measurements in the same irradiation field, and the measurement results were mutually compared. The participated in the exercise to measure the doses of gamma rays and neutron from SILENE by using thermoluminescence dosimeters (TLD's) and an alanine dosimeter. In this examination, the derived evaluation formulae for obtaining a tissue-absorbed dose from measured value (ambient dose equivalent) of TLD for neutron. We reported the tissue-absorbed dose computed using this evaluation formula to OECD/NEA. TLD's for neutron were irradiated in the TRACY facility to verify the evaluation formulae. The results of TLD's were compared with the calculations of MCNP and measurements with alanine dose meter. We found that the ratio of the dose b...

  4. 2010 Criticality Accident Alarm System Benchmark Experiments At The CEA Valduc SILENE Facility

    International Nuclear Information System (INIS)

    Miller, Thomas Martin; Dunn, Michael E.; Wagner, John C.; McMahan, Kimberly L.; Authier, Nicolas; Jacquet, Xavier; Rousseau, Guillaume; Wolff, Herve; Piot, Jerome; Savanier, Laurence; Baclet, Nathalie; Lee, Yi-kang; Masse, Veronique; Trama, Jean-Christophe; Gagnier, Emmanuel; Naury, Sylvie; Lenain, Richard; Hunter, Richard; Kim, Soon; Dulik, George Michael; Reynolds, Kevin H.

    2011-01-01

    Several experiments were performed at the CEA Valduc SILENE reactor facility, which are intended to be published as evaluated benchmark experiments in the ICSBEP Handbook. These evaluated benchmarks will be useful for the verification and validation of radiation transport codes and evaluated nuclear data, particularly those that are used in the analysis of CAASs. During these experiments SILENE was operated in pulsed mode in order to be representative of a criticality accident, which is rare among shielding benchmarks. Measurements of the neutron flux were made with neutron activation foils and measurements of photon doses were made with TLDs. Also unique to these experiments was the presence of several detectors used in actual CAASs, which allowed for the observation of their behavior during an actual critical pulse. This paper presents the preliminary measurement data currently available from these experiments. Also presented are comparisons of preliminary computational results with Scale and TRIPOLI-4 to the preliminary measurement data.

  5. Dioecious Silene latifolia plants show sexual dimorphism in the vegetative stage

    Czech Academy of Sciences Publication Activity Database

    Žlůvová, Jitka; Žák, Jiří; Janoušek, Bohuslav; Vyskot, Boris

    2010-01-01

    Roč. 10, č. 208 (2010), s. 1-5 ISSN 1471-2229 R&D Projects: GA AV ČR(CZ) KJB600040801; GA AV ČR(CZ) IAA600040801; GA ČR(CZ) GAP501/10/0102 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : sex dimorphism * Silene latifolia * dioecious plants Subject RIV: BO - Biophysics Impact factor: 4.085, year: 2010

  6. Patterns of molecular evolution in dioecious and non-dioecious Silene

    Czech Academy of Sciences Publication Activity Database

    Kaefer, J.; Talianová, Martina; Bigot, T.; Michu, Elleni; Gueguen, L.; Widmer, A.; Žlůvová, Jitka; Glemin, S.; Marais, G.A.B.

    2013-01-01

    Roč. 26, č. 2 (2013), s. 335-346 ISSN 1010-061X R&D Projects: GA ČR(CZ) GA521/08/0932; GA ČR(CZ) GD204/09/H002; GA ČR(CZ) GBP501/12/G090 Institutional support: RVO:68081707 Keywords : purifying selection * reproductive systems * Silene latifolia Subject RIV: BO - Biophysics Impact factor: 3.483, year: 2013

  7. TRIPOLI calculation of the neutron field in the hall of the SILENE reactor

    International Nuclear Information System (INIS)

    Bourdet, L.

    1986-05-01

    This study concerns the utilization of the experimental reactor SILENE as radiation source. Its aim is to get a theoretical estimation of the neutron field characteristics in different points of the irradiation hall (spectra, fluences, equivalents of biological doses and reaction yields). These estimations are compared to results obtained by several experimental techniques; they allow to know better this neutron field with or without lead shield [fr

  8. Vicariance, long-distance dispersal, and regional extinction-recolonization dynamics explain the disjunct circumpolar distribution of the arctic-alpine plant Silene acaulis.

    Science.gov (United States)

    Gussarova, Galina; Allen, Geraldine A; Mikhaylova, Yulia; McCormick, Laurie J; Mirré, Virginia; Marr, Kendrick L; Hebda, Richard J; Brochmann, Christian

    2015-10-01

    Many arctic-alpine species have vast geographic ranges, but these may encompass substantial gaps whose origins are poorly understood. Here we address the phylogeographic history of Silene acaulis, a perennial cushion plant with a circumpolar distribution except for a large gap in Siberia. We assessed genetic variation in a range-wide sample of 103 populations using plastid DNA (pDNA) sequences and AFLPs (amplified fragment length polymorphisms). We constructed a haplotype network and performed Bayesian phylogenetic analyses based on plastid sequences. We visualized AFLP patterns using principal coordinate analysis, identified genetic groups using the program structure, and estimated genetic diversity and rarity indices by geographic region. The history of the main pDNA lineages was estimated to span several glaciations. AFLP data revealed a distinct division between Beringia/North America and Europe/East Greenland. These two regions shared only one of 17 pDNA haplotypes. Populations on opposite sides of the Siberian range gap (Ural Mountains and Chukotka) were genetically distinct and appear to have resulted from postglacial leading-edge colonizations. We inferred two refugia in North America (Beringia and the southern Rocky Mountains) and two in Europe (central-southern Europe and northern Europe/East Greenland). Patterns in the East Atlantic region suggested transoceanic long-distance dispersal events. Silene acaulis has a highly dynamic history characterized by vicariance, regional extinction, and recolonization, with persistence in at least four refugia. Long-distance dispersal explains patterns across the Atlantic Ocean, but we found no evidence of dispersal across the Siberian range gap. © 2015 Botanical Society of America.

  9. Effect of genotype, Cr(III and Cr(VI on plant growth and micronutrient status in Silene vulgaris (Moench

    Directory of Open Access Journals (Sweden)

    A. E. Pradas-del-Real

    2013-06-01

    Full Text Available Chromium released into the environment from industrial activities has become an important environmental concern. Silene vulgaris has been proven to be tolerant to many heavy metals, so it is considered an interesting species in the revegetation and restoration of polluted soils, but no information is available about its response to Cr. The objective of this work was to study uptake and influence on plant growth of Cr(III and Cr(VI in six genotypes (four hermaphrodites and two females of S. vulgaris from different sites of Madrid (Spain. Plants were treated for 12 days with 60 µM of Cr(III or Cr(VI in semihydroponics. Dry weights, soil-plant analysis development values (SPAD reading with chlorophylls and micronutrient and total Cr concentrations were determined. Metal uptake was higher in presence of Cr(VI than of Cr(III and poorly translocated to the shoots. In both cases S. vulgaris did not show visual toxicity symptoms, biomass reduction, or differences among SPAD values as consequence of Cr additions. However genotypes SV36 and SV38 showed Fe and Mn imbalance. This is the first report on the relatively good performance of hermaphrodite and female S. vulgaris genotypes in Cr uptake and physiological traits, but further studies will be necessary to elucidate the mechanisms by which the gender may influence these variables. S. vulgaris presented high diversity at genotypic level; the treatment with hexavalent Cr increased the differences among genotypes so the use of cuttings from an homogeneous genotype seems to be an adequate method for the study of this species.

  10. Structure and evolution of Apetala3, a sex-linked gene in Silene latifolia

    Czech Academy of Sciences Publication Activity Database

    Čegan, Radim; Marais, G.A.B.; Kubeková, Hana; Blavet, N.; Widmer, A.; Vyskot, Boris; Doležel, Jaroslav; Šafář, Jan; Hobza, Roman

    2010-01-01

    Roč. 10, č. 180 (2010), s. 1-10 ISSN 1471-2229 R&D Projects: GA ČR(CZ) GA522/09/0083; GA ČR(CZ) GD204/09/H002; GA AV ČR(CZ) KJB600040901 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702; CEZ:AV0Z50380511 Keywords : sex chromosomes evolution * Apetala3 * Silene Subject RIV: BO - Biophysics Impact factor: 4.085, year: 2010

  11. Next Generation Sequencing-Based Analysis of Repetitive DNA in the Model Dioceous Plant Silene latifolia

    Czech Academy of Sciences Publication Activity Database

    Macas, Jiří; Kejnovský, Eduard; Neumann, Pavel; Novák, Petr; Koblížková, Andrea; Vyskot, Boris

    2011-01-01

    Roč. 6, č. 11 (2011), e27335 E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) OC10037; GA MŠk(CZ) LC06004; GA MŠk(CZ) LH11058; GA ČR(CZ) GAP501/10/0102; GA ČR(CZ) GAP305/10/0930 Institutional research plan: CEZ:AV0Z50510513; CEZ:AV0Z50040702 Keywords : Plant genome * Sequencing-Based Analyses * Repetitive DNA * Silene latifolia Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.092, year: 2011

  12. Identification of a Novel Retrotransposon with Sex Chromosome-Specific Distribution in Silene latifolia

    Czech Academy of Sciences Publication Activity Database

    Králová, Tereza; Čegan, Radim; Kubát, Zdeněk; Vrána, Jan; Vyskot, Boris; Vogel, Ivan; Kejnovský, Eduard; Hobza, Roman

    2014-01-01

    Roč. 143, 1-3 (2014), s. 87-95 ISSN 1424-8581 R&D Projects: GA MŠk(CZ) LM2010005; GA ČR(CZ) GAP501/10/0102; GA ČR(CZ) GAP501/12/2220; GA ČR(CZ) GAP305/10/0930; GA ČR(CZ) GA522/09/0083; GA MŠk(CZ) LO1204 Institutional support: RVO:68081707 Keywords : Microdissection * Sex chromosomes * Silene latifolia (white campion) Subject RIV: BO - Biophysics; EF - Botanics (UEB-Q) Impact factor: 1.561, year: 2014

  13. Feasibility of reactivity worth measurements by perturbation method with Caliban and Silene experimental reactors

    Energy Technology Data Exchange (ETDEWEB)

    Casoli, Pierre; Authier, Nicolas [Commissariat a l' Energie Atomique, Centre d' Etudes de Valduc, 21120 Is-Sur-Tille (France)

    2008-07-01

    Reactivity worth measurements of material samples put in the central cavities of nuclear reactors allow to test cross section nuclear databases or to extract information about the critical masses of fissile elements. Such experiments have already been completed on the Caliban and Silene experimental reactors operated by the Criticality and Neutronics Research Laboratory of Valduc (CEA, France) using the perturbation measurement technique. Calculations have been performed to prepare future experiments on new materials, such as light elements, structure materials, fission products or actinides. (authors)

  14. Inter-populations genetic and morphological diversity in three Silene ...

    African Journals Online (AJOL)

    enoho

    2012-03-30

    Mar 30, 2012 ... 2Biology Department, School of Basic Sciences, Science and Research Branch, Islamic Azad University (SRBIAU), ... other populations in both morphological and molecular features. ... species with world-wide distribution.

  15. SILENE and TDT: A code for collision probability calculations in XY geometries

    International Nuclear Information System (INIS)

    Sanchez, R.; Stankovski, Z.

    1993-01-01

    Collision probability methods are routinely used for cell and assembly multigroup transport calculations in core design tasks. Collision probability methods use a specialized tracking routine to compute neutron trajectories within a given geometric object. These trajectories are then used to generate the appropriate collision matrices in as many groups as required. Traditional tracking routines are based on open-quotes globalclose quotes geometric descriptions (such as regular meshes) and are not able to cope with the geometric detail required in actual core calculations. Therefore, users have to modify their geometry in order to match the geometric model accepted by the tracking routine, introducing thus a modeling error whose evaluation requires the use of a open-quotes referenceclose quotes method. Recently, an effort has been made to develop more flexible tracking routines either by directly adopting tracking Monte Carlo techniques or by coding of complicated geometries. Among these, the SILENE and TDT package is being developed at the Commissariat a l' Energie Atomique to provide routine as well as reference calculations in arbitrarily shaped XY geometries. This package combines a direct graphical acquisition system (SILENE) together with a node-based collision probability code for XY geometries (TDT)

  16. Arsenate tolerance in Silene paradoxa does not rely on phytochelatin-dependent sequestration

    International Nuclear Information System (INIS)

    Arnetoli, Miluscia; Vooijs, Riet; Bookum, Wilma ten; Galardi, Francesca; Gonnelli, Cristina; Gabbrielli, Roberto; Schat, Henk; Verkleij, Jos A.C.

    2008-01-01

    Arsenate tolerance, As accumulation and As-induced phytochelatin accumulation were compared in populations of Silene paradoxa, one from a mine site enriched in As, Cu and Zn, the other from an uncontaminated site. The mine population was significantly more arsenate-tolerant. Arsenate uptake and root-to-shoot transport were slightly but significantly higher in the non-mine plants. The difference in uptake was quantitatively insufficient to explain the difference in tolerance between the populations. As accumulation in the roots was similar in both populations, but the mine plants accumulated much less phytochelatins than the non-mine plants. The mean phytochelatin chain length, however, was higher in the mine population, possibly due to a constitutively lower cellular glutathione level. It is argued that the mine plants must possess an arsenic detoxification mechanism other than arsenate reduction and subsequent phytochelatin-based sequestration. This alternative mechanism might explain at least some part of the superior tolerance in the mine plants. - Neither decreased uptake nor phytochelatins seem to play a role in the As tolerance in Silene paradoxa

  17. Analytical evaluation of dose measurement of critical accident at SILENE (Contract research)

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Takemi; Tonoike, Kotaro; Miyoshi, Yoshinori [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    Institute for Radioprotection and Nuclear Safety (IRSN) and the OECD Nuclear Energy Agency (NEA) jointly organized SILENE Accident Dosimetry Intercomparison Exercise to intercompare the dose measurement systems of participating countries. Each participating country carried out dose measurements in the same irradiation field, and the measurement results were mutually compared. The authors participated in the exercise to measure the doses of gamma rays and neutron from SILENE by using thermoluminescence dosimeters (TLD's) and an alanine dosimeter. In this examination, the authors derived evaluation formulae for obtaining a tissue-absorbed dose from measured value (ambient dose equivalent) of TLD for neutron. We reported the tissue-absorbed dose computed using this evaluation formula to OECD/NEA. TLD's for neutron were irradiated in the TRACY facility to verify the evaluation formulae. The results of TLD's were compared with the calculations of MCNP and measurements with alanine dose meter. We found that the ratio of the dose by the evaluation formula to the measured value by the alanine dosimeter was 0.94 and the formula agreed within 6%. From examination of this TRACY, we can conclude that the value reported to OECD/NEA has equivalent accuracy. (author)

  18. Criticality accident dosimetry systems: an international intercomparison at the SILENE reactor in 2002.

    Science.gov (United States)

    Médioni, R; Asselineau, B; Verrey, B; Trompier, F; Itié, C; Texier, C; Muller, H; Pelcot, G; Clairand, I; Jacquet, X; Pochat, J L

    2004-01-01

    In criticality accident dosimetry and more generally for high dose measurements, special techniques are used to measure separately the gamma ray and neutron components of the dose. To improve these techniques and to check their dosimetry systems (physical and/or biological), a total of 60 laboratories from 29 countries (America, Europe, Asia) participated in an international intercomparaison, which took place in France from 9 to 21 June 2002, at the SILENE reactor in Valduc and at a pure gamma source in Fontenay-aux-Roses. This intercomparison was jointly organised by the IRSN and the CEA with the help of the NEA/OCDE and was partly supported by the European Communities. This paper describes the aim of this intercomparison, the techniques used by the participants and the two radiation sources and their characteristics. The experimental arrangements of the dosemeters for the irradiations in free air or on phantoms are given. Then the dosimetric quantities measured and reported by the participants are summarised, analysed and compared with the reference values. The present paper concerns only the physical dosimetry and essentially experiments performed on the SILENE facility. The results obtained with the biological dosimetry are published in two other papers of this issue.

  19. STUDIES CONCERNING THE IMPORTANCE OF THE FLORIFEROUS SPECIES FOR PARKS AND GARDENS

    Directory of Open Access Journals (Sweden)

    Maria Violeta Dinuta

    2012-04-01

    Full Text Available The study aims the evaluation and scientific documentation for some floral species of spontaneous flora for understanding the ecological requirements and decorative and terapeutical characteristics; choose the most effective and rapid methods for obtaining planting material, to preserve natural biodiversity and their propagation for ornamental and medicinal purposes. The analysed species belonged to Ranunculaceae family (Hepatica transsilvanica Fuss, Iridaceae family (Iris aphylla L, Crocus vernus L, Caryophyllaceae family (Dianthus spiculifollius and Asteraceae family (Arnica montana L.

  20. Genetic variation of inbreeding depression among floral and fitness traits in Silene nutans

    DEFF Research Database (Denmark)

    Thiele, Jan; Hansen, Thomas Møller; Siegismund, Hans Redlef

    2010-01-01

    The magnitude and variation of inbreeding depression (ID) within populations is important for the evolution and maintenance of mixed mating systems. We studied ID and its genetic variation in a range of floral and fitness traits in a small and large population of the perennial herb Silene nutans......, using controlled pollinations in a fully factorial North Carolina II design. Floral traits and early fitness traits, that is seed mass and germination rate, were not much affected by inbreeding (delta0.4). Lack of genetic correlations indicated that ID in floral, early and late traits is genetically...... was statistically significant in most floral and all seed traits, but not in late fitness traits. However, some paternal families had delta...

  1. Identification and characterization of a bacteria-like sequence in the genome of some Silene species

    Czech Academy of Sciences Publication Activity Database

    Talianová, Martina; Žlůvová, Jitka; Hobza, Roman; Vyskot, Boris; Janoušek, Bohuslav

    2012-01-01

    Roč. 56, č. 2 (2012), s. 247-253 ISSN 0006-3134 R&D Projects: GA ČR(CZ) GA521/08/0932; GA ČR(CZ) GA522/09/0083; GA ČR(CZ) GD204/09/H002 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : horizontal gene transfer * microdissection * phylogenetic analysis Subject RIV: BO - Biophysics Impact factor: 1.692, year: 2012

  2. Comparative analysis of a plant pseudoautosomal region (PAR) in Silene latifolia with the corresponding S. vulgaris autosome

    Czech Academy of Sciences Publication Activity Database

    Blavet, N.; Blavet, Hana; Čegan, Radim; Zemp, N.; Ždánská, Jana; Janoušek, Bohuslav; Hobza, Roman; Widmer, A.

    2012-01-01

    Roč. 13, č. 226 (2012), s. 1-9 ISSN 1471-2164 R&D Projects: GA ČR(CZ) GA522/09/0083; GA ČR GBP501/12/G090 Institutional research plan: CEZ:AV0Z50040702 Keywords : BAC library * pseudoautosomal region * Silene latifolia Subject RIV: BO - Biophysics Impact factor: 4.397, year: 2012

  3. Nomenclatural notes on the genus Pteranthus (Caryophyllaceae) with lectotypification of the name Camphorosma pteanthus and Pteranthus trigynus, and comments on Forsskål's seeds sent from Egypt

    DEFF Research Database (Denmark)

    Iamonico, Dulio; Friis, Ib; Jarvis, Charles

    2015-01-01

    The nomenclatural history of the genus Pteranthus ( Caryophyllaceae) is reviewed. Original material of Camphorosma pteranthus and Pteranthus dichotomus came from a single gathering made by Forsskål in the desert outside Cairo, Egypt, in March 1762. The original material of C. pteranthus was grown...... from seed collected with the herbarium material of P. dicho­tomus. Pteranthus dichotomus is therefore considered a replacement name for C. pteranthus and lectotypified with the same specimen, no. 165.5 LINN (right-hand plant). A supporting epitype is chosen from flowering herbarium material of the same...

  4. Biological dosimetry after criticality accidents. Intercomparison exercise in the Silene Reactor - France; Dosimetria biologica en accidentes de criticidad. Ejercicio de intercomparacion en el Reactor Silene - Francia

    Energy Technology Data Exchange (ETDEWEB)

    Di Giorgio, Marina; Vallerga, Maria B; Taja, Maria R [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina); arn gov ar, E-mail: mdigiorg@cae

    2004-07-01

    The Institute of Radiation Protection and Nuclear Safety Institute (IRSN) organized an international biological dosimetry intercomparison, at the SILENE experimental reactor (Valduc, France), simulating different criticality scenarios: bare source 4 Gy, lead shield source 1 and 2 Gy and gamma pure {sup 60}Co source 2 Gy. Fifteen laboratories were involved in this exercise, including the Argentine Biological Dosimetry Laboratory. The purposes of the intercomparison were: 1) To compare the unstable chromosome aberration (UCA) frequency observed by the different laboratories; and 2) To compare the dose estimation for gamma rays and neutrons. The objects of the present work were: I) To compare the mean frequency of UCA observed by the Argentine laboratory with the mean frequency observed by the participant laboratories as a whole. II) To compare the dose estimates performed by the Argentine lab with those estimated by the other laboratories involved in the second stage of the intercomparison. Overall, the mean frequencies of UCA and the correspondent 95% confidence limits obtained by the Argentine lab were consistent with the results obtained by the laboratories as a whole. For the gamma pure scenario, smaller variations were observed among laboratories in terms of dose (CV=18,2%) than in terms of frequency (CV=30,1%). For the mixed field scenarios, only four laboratories, including the Argentine lab, estimated gamma and neutron components of the total dose and just two (Argentine lab and lab 12) were in agreement with the given physical doses. The 1 Gy experiment presented lesser variations both in terms of frequency and dose than the other two scenarios. For the 4 and 2 Gy experiments, variations in neutron dose were more significant than variations in gamma dose, related to the magnitude of the dose. The results suggest that intercomparison exercises jointly with the accreditation of biological dosimetry by cytogenetic service laboratories, in compliance with ISO

  5. Paradoxical effects of density on measurement of copper tolerance in Silene paradoxa L.

    Science.gov (United States)

    Capuana, Maurizio; Colzi, Ilaria; Buccianti, Antonella; Coppi, Andrea; Palm, Emily; Del Bubba, Massimo; Gonnelli, Cristina

    2018-01-01

    This work investigated if the assessment of tolerance to trace metals can depend on plant density in the experimental design. A non-metallicolous and a metallicolous populations of Silene paradoxa were hydroponically cultivated at increasing density and in both the absence (-Cu conditions) and excess of copper (+Cu conditions). In -Cu conditions, the metallicolous population showed a lower susceptibility to plant density in comparison to the non-metallicolous one, explained by a higher capacity of the metallicolous population to exploit resources. In +Cu conditions, an alleviating effect of increasing density was found in roots. Such effect was present to a greater extent in the non-metallicolous population, thus making the populations equally copper-tolerant at the highest density used. In shoots, an additive effect of increasing plant density to copper toxicity was reported. Its higher intensity in the metallicolous population reverted the copper tolerance relationship at the highest plant densities used. In both populations, a density-induced decrease in root copper accumulation was observed, thus concurring to the reported mitigation in +Cu conditions. Our work revealed the importance of density studies on the optimization of eco-toxicological bioassays and of metal tolerance assessment and it can be considered the first example of an alleviating effect of increasing plant number on copper stress in a metallophyte.

  6. Manganese Silylene Hydride Complexes: Synthesis and Reactivity with Ethylene to Afford Silene Hydride Complexes.

    Science.gov (United States)

    Price, Jeffrey S; Emslie, David J H; Britten, James F

    2017-05-22

    Reaction of the ethylene hydride complex trans-[(dmpe) 2 MnH(C 2 H 4 )] (1) with Et 2 SiH 2 at 20 °C afforded the silylene hydride [(dmpe) 2 MnH(=SiEt 2 )] (2 a) as the trans-isomer. By contrast, reaction of 1 with Ph 2 SiH 2 at 60 °C afforded [(dmpe) 2 MnH(=SiPh 2 )] (2 b) as a mixture of the cis (major) and trans (minor) isomers, featuring a Mn-H-Si interaction in the former. The reaction to form 2 b also yielded [(dmpe) 2 MnH 2 (SiHPh 2 )] (3 b); [(dmpe) 2 MnH 2 (SiHR 2 )] (R=Et (3 a) and Ph (3 b)) were accessed cleanly by reaction of 2 a and 2 b with H 2 , and the analogous reactions with D 2 afforded [(dmpe) 2 MnD 2 (SiHR 2 )] exclusively. Both 2 a and 2 b engaged in unique reactivity with ethylene, generating the silene hydride complexes cis-[(dmpe) 2 MnH(R 2 Si=CHMe)] (R=Et (4 a), Ph (4 b)). Compounds trans-2 a, cis-2 b, 3 b, and 4 b were crystallographically characterized, and bonding in 2 a, 2 b, 4 a, and 4 b was probed computationally. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Determinants of genetic structure in a nonequilibrium metapopulation of the plant Silene latifolia.

    Directory of Open Access Journals (Sweden)

    Peter D Fields

    Full Text Available Population genetic differentiation will be influenced by the demographic history of populations, opportunities for migration among neighboring demes and founder effects associated with repeated extinction and recolonization. In natural populations, these factors are expected to interact with each other and their magnitudes will vary depending on the spatial distribution and age structure of local demes. Although each of these effects has been individually identified as important in structuring genetic variance, their relative magnitude is seldom estimated in nature. We conducted a population genetic analysis in a metapopulation of the angiosperm, Silene latifolia, from which we had more than 20 years of data on the spatial distribution, demographic history, and extinction and colonization of demes. We used hierarchical Bayesian methods to disentangle which features of the populations contributed to among population variation in allele frequencies, including the magnitude and direction of their effects. We show that population age, long-term size and degree of connectivity all combine to affect the distribution of genetic variance; small, recently-founded, isolated populations contributed most to increase FST in the metapopulation. However, the effects of population size and population age are best understood as being modulated through the effects of connectivity to other extant populations, i.e. FST diminishes as populations age, but at a rate that depends how isolated the population is. These spatial and temporal correlates of population structure give insight into how migration, founder effect and within-deme genetic drift have combined to enhance and restrict genetic divergence in a natural metapopulation.

  8. Effect of Copper on Fatty-Acid Composition and Peroxidation of Lipids in the Roots of Copper Tolerant and Sensitive Silene-Cucubalus.

    NARCIS (Netherlands)

    De Vos, C.H.R.; TenBookum, W.M.; Vooijs, R.; Schat, H.; De Kok, L.J.

    1993-01-01

    The effect of high copper exposure in vivo on the lipid and fatty acid composition and lipid peroxidation was studied in the roots of plants from one copper sensitive and two copper tolerant genotypes of Silene cucubalus. At 0.5 muM Cu (control treatment) the compositions of lipids and fatty acids

  9. The 2″-O-glucosylation of vitexin and isovitexin in petals of Silene alba is catalysed by two different enzymes

    NARCIS (Netherlands)

    Heinsbroek, R.; Brederode, J. van; Nigtevecht, G. van; Maas, J.; Kamsteeg, J.; Besson, E.; Chopin, J.

    1980-01-01

    Two separate genes, Fg and Vg, which govern the presence of isovitexin 2″-O-glucoside and vitexin 2″-O-glucoside respectively in the petals of Silene alba control different glucosyltransferases. In Vg/Vg,fg/fg plants no isovitexin 2″-O-glucosyltransferase was present and in vg/vg,Fg/Fg plants no

  10. Biological dosimetry after criticality accidents. Intercomparison exercise in the Silene Reactor - France

    International Nuclear Information System (INIS)

    Di Giorgio, Marina; Vallerga, Maria B.; Taja, Maria R.

    2004-01-01

    The Institute of Radiation Protection and Nuclear Safety Institute (IRSN) organized an international biological dosimetry intercomparison, at the SILENE experimental reactor (Valduc, France), simulating different criticality scenarios: bare source 4 Gy, lead shield source 1 and 2 Gy and gamma pure 60 Co source 2 Gy. Fifteen laboratories were involved in this exercise, including the Argentine Biological Dosimetry Laboratory. The purposes of the intercomparison were: 1) To compare the unstable chromosome aberration (UCA) frequency observed by the different laboratories; and 2) To compare the dose estimation for gamma rays and neutrons. The objects of the present work were: I) To compare the mean frequency of UCA observed by the Argentine laboratory with the mean frequency observed by the participant laboratories as a whole. II) To compare the dose estimates performed by the Argentine lab with those estimated by the other laboratories involved in the second stage of the intercomparison. Overall, the mean frequencies of UCA and the correspondent 95% confidence limits obtained by the Argentine lab were consistent with the results obtained by the laboratories as a whole. For the gamma pure scenario, smaller variations were observed among laboratories in terms of dose (CV=18,2%) than in terms of frequency (CV=30,1%). For the mixed field scenarios, only four laboratories, including the Argentine lab, estimated gamma and neutron components of the total dose and just two (Argentine lab and lab 12) were in agreement with the given physical doses. The 1 Gy experiment presented lesser variations both in terms of frequency and dose than the other two scenarios. For the 4 and 2 Gy experiments, variations in neutron dose were more significant than variations in gamma dose, related to the magnitude of the dose. The results suggest that intercomparison exercises jointly with the accreditation of biological dosimetry by cytogenetic service laboratories, in compliance with ISO

  11. Photosynthetic responses to temperature and light of Antarctic and Andean populations of Colobanthus quitensis (Caryophyllaceae Respuestas fotosintéticas a la temperatura y a la luz de poblaciones antarticas y andinas de Colobanthus quitensis (Caryophyllaceae

    Directory of Open Access Journals (Sweden)

    ÁNGELA SIERRA-ALMEIDA

    2007-09-01

    Full Text Available Colobanthus quitensis (Kunth, 1831 Bartling (Caryophyllaceae is characterized by a wide latitudinal distribution, ranging between the tropical high Andes and the Antarctic Peninsula. Although both habitat types are characterized by cold and freezing temperatures, important microclimatic differences exist during the growing season. Hence, important differences in the response of the photosynthetic apparatus to abiotic factors could be expected between Antarctic and Andean populations of C. quitensis. We studied the relationship between net photosynthesis, leaf temperature and light intensity in two populations of C. quitensis, one from La Parva in the Andes of central Chile and the other from King George Island, in the Maritime Antarctic. Plants from both populations were grown in the laboratory at 15 °C under 250 μmol photons m-2 s-1, with a 16/8 h light/dark photoperiod. Twenty plants (about two months old of each population were transferred to a 4 °C chamber with the same light and photoperiod conditions as above to assess the photosynthetic acclimation capacity. At 15 °C, populations differed in their optimum leaf temperature for photosynthesis, being 24.0 °C in individuals from the Andes and 18.6 °C in individuals from the Antarctic. In contrast, Antarctic individuals showed the highest net photosynthesis rate under both temperature treatments, with the lowest light compensation and saturation points. Antarctic individuals had higher photosynthetic activity at lower temperatures compared to individuals from the Andes. Our results suggest that C. quitensis has adapted photosynthetic performance of individuals growing in different localities to the prevailing climatic conditions. Differences in photosynthetic responses to temperature and light are discussed in relation to ecotypic differentiation between two populations studiedColobanthus quitensis es una especie ampliamente distribuida, que crece desde los Andes tropicales hasta la Pen

  12. Participation of IRD/CNEN-Br in International Intercomparison of Criticality Accident Dosimetry Systems at Silene reactor, France

    International Nuclear Information System (INIS)

    Mauricio, Claudia Lucia P.; Fonseca, Evaldo S. da

    1996-01-01

    IRD has participated in an International Intercomparison of Criticality Accident Dosimetry Systems at the SILENE reactor, France on June 1993. The dosemeters were irradiated on phantoms and free in air, in bare and lead shield reactor pulses, simulating different irradiation fields that can be found in criticality accidents. Comparing with the reference measurements, the calculated mean neutron kerma found by IRD was only 2% greater for lead shield and 14% greater for bare reactor. For gamma absorbed dose, the differences were, respectively + 22% and -9% for the dosemeters free in air and -19% and -9% for dosemeters on phantoms. IRD results are closer to the real values than the mean values measured by the participants. IRD results show a good performance if its simple criticality accident system. (author)

  13. Under fungal attack on a metalliferous soil: ROS or not ROS? Insights from Silene paradoxa L. growing under copper stress

    International Nuclear Information System (INIS)

    Taiti, Cosimo; Giorni, Elisabetta; Colzi, Ilaria; Pignattelli, Sara; Bazihizina, Nadia; Buccianti, Antonella; Luti, Simone; Pazzagli, Luigia; Mancuso, Stefano; Gonnelli, Cristina

    2016-01-01

    We investigated how the adaptation to metalliferous environments can influence the plant response to biotic stress. In a metallicolous and a non-metallicolous population of Silene paradoxa the induction of oxidative stress and the production of callose and volatiles were evaluated in the presence of copper and of the PAMP fungal protein cerato-platanin, separately and in combination. Our results showed incompatibility between the ordinary ROS-mediated response to fungal attack and the acquired mechanisms of preventing oxidative stress in the tolerant population. A similar situation was also demonstrated by the sensitive population growing in the presence of copper but, in this case, with a lack of certain responses, such as callose production. In addition, in terms of the joint behaviour of emitted volatiles, multivariate statistics showed that not only did the populations respond differently to the presence of copper or biotic stress, but also that the biotic and abiotic stresses interacted in different ways in the two populations. Our results demonstrated that the same incompatibility of hyperaccumulators in ROS-mediated biotic stress signals also seemed to be exhibited by the excluder metallophyte, but without the advantage of being able to rely on the elemental defence for plant protection from natural enemies. - Highlights: • Silene paradoxa plants from metalliferous and nonmetalliferous soil were studied. • Plants were exposed to Cerato-platanin in presence/absence of Cu in culture media. • ROS response was fully present in nonmetallicolous plants only in the absence of Cu. • Similar ROS response in metallicolous plants with or without Cu. - The adaptation to high concentrations of copper was found to interfere with the ordinary ROS-mediated response to fungal attack in an excluder metallophyte.

  14. Study of Plant Species Composition of Grasslands in Mugla Village Region (Western Rhodopes, South Bulgaria

    Directory of Open Access Journals (Sweden)

    Plamen S. Stoyanov

    2016-06-01

    Full Text Available The study presents data on the diversity of grass species in the region of the village of Mugla (the Western Rhodopes. One hundred forty-one species of higher plants belonging to 40families were registered. (Apiaceae, Aspleniaceae, Asteraceae, Boraginaceae, Brassicaceae,Campanulaceae, Caryophyllaceae, Cistaceae, Cyperaceae, Dipsacaceae, Equisetaceae, Ericaceae,Euphorbiaceae, Fabaceae, Gentianaceae, Geraniaceae, Gesneriaceae, Hypericaceae, Juncaceae,Lamiaceae, Lemnaceae, Liliaceae, Linaceae, Menyanthaceae, Oleacea, Onagraceae, Orchidaceae,Parnassiaceae, Plantaginaceae, Plumbaginaceae, Poaceae, Polygalaceae, Primulaceae,Ranunculaceae, Rosaceae, Rubiaceae, Saxifragaceae, Scrophulariaceae, Valerianaceae andViolaceae. Their conservation status was presented, as well as medicinal plants.

  15. The slowdown of Y chromosome expansion in dioecious Silene latifolia due to DNA loss and male-specific silencing of retrotransposons

    Czech Academy of Sciences Publication Activity Database

    Puterova, Janka; Kubát, Zdeněk; Kejnovský, Eduard; Jesionek, Wojciech; Čížková, Jana; Vyskot, Boris; Hobza, Roman

    2018-01-01

    Roč. 19, FEB2018 (2018) ISSN 1471-2164 R&D Projects: GA ČR GJ15-21523Y Institutional support: RVO:68081707 ; RVO:61389030 Keywords : sex-linked genes * plant silene * transposable elements Subject RIV: EF - Botanics; EF - Botanics (UEB-Q) OBOR OECD: Plant sciences, botany; Plant sciences, botany (UEB-Q) Impact factor: 3.729, year: 2016

  16. Two Silene vulgaris copper transporters residing in different cellular compartments confer copper hypertolerance by distinct mechanisms when expressed in Arabidopsis thaliana.

    Science.gov (United States)

    Li, Yanbang; Iqbal, Mazhar; Zhang, Qianqian; Spelt, Cornelis; Bliek, Mattijs; Hakvoort, Henk W J; Quattrocchio, Francesca M; Koes, Ronald; Schat, Henk

    2017-08-01

    Silene vulgaris is a metallophyte of calamine, cupriferous and serpentine soils all over Europe. Its metallicolous populations are hypertolerant to zinc (Zn), cadmium (Cd), copper (Cu) or nickel (Ni), compared with conspecific nonmetallicolous populations. These hypertolerances are metal-specific, but the underlying mechanisms are poorly understood. We investigated the role of HMA5 copper transporters in Cu-hypertolerance of a S. vulgaris copper mine population. Cu-hypertolerance in Silene is correlated and genetically linked with enhanced expression of two HMA5 paralogs, SvHMA5I and SvHMA5II, each of which increases Cu tolerance when expressed in Arabidopsis thaliana. Most Spermatophytes, except Brassicaceae, possess homologs of SvHMA5I and SvHMA5II, which originate from an ancient duplication predating the appearance of spermatophytes. SvHMA5II and the A. thaliana homolog AtHMA5 localize in the endoplasmic reticulum and upon Cu exposure move to the plasma membrane, from where they are internalized and degraded in the vacuole. This resembles trafficking of mammalian homologs and is apparently an extremely ancient mechanism. SvHMA5I, instead, neofunctionalized and always resides on the tonoplast, likely sequestering Cu in the vacuole. Adaption of Silene to a Cu-polluted soil is at least in part due to upregulation of two distinct HMA5 transporters, which contribute to Cu hypertolerance by distinct mechanisms. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  17. Salicylic acid promotes plant growth and salt-related gene expression in Dianthus superbus L. (Caryophyllaceae) grown under different salt stress conditions.

    Science.gov (United States)

    Zheng, Jian; Ma, Xiaohua; Zhang, Xule; Hu, Qingdi; Qian, Renjuan

    2018-03-01

    Salt stress is a critical factor that affects the growth and development of plants. Salicylic acid (SA) is an important signal molecule that mitigates the negative effects of salt stress on plants. To elucidate salt tolerance in large pink Dianthus superbus L. (Caryophyllaceae) and the regulatory mechanism of exogenous SA on D. superbus under different salt stresses, we conducted a pot experiment to evaluate leaf biomass, leaf anatomy, soluble protein and sugar content, and the relative expression of salt-induced genes in D. superbus under 0.3, 0.6, and 0.9% NaCl conditions with and without 0.5 mM SA. The result showed that exposure of D. superbus to salt stress lead to a decrease in leaf growth, soluble protein and sugar content, and mesophyll thickness, together with an increase in the expression of MYB and P5CS genes. Foliar application of SA effectively increased leaf biomass, soluble protein and sugar content, and upregulated the expression of MYB and P5CS in the D. superbus , which facilitated in the acclimation of D. superbus to moderate salt stress. However, when the plants were grown under severe salt stress (0.9% NaCl), no significant difference in plant physiological responses and relevant gene expression between plants with and without SA was observed. The findings of this study suggest that exogenous SA can effectively counteract the adverse effects of moderate salt stress on D. superbus growth and development.

  18. Neutron Activation Foil and Thermoluminescent Dosimeter Responses to a Lead Reflected Pulse of the CEA Valduc SILENE Critical Assembly

    International Nuclear Information System (INIS)

    Miller, Thomas Martin; Celik, Cihangir; Isbell, Kimberly McMahan; Lee, Yi-kang; Gagnier, Emmanuel; Authier, Nicolas; Piot, Jerome; Jacquet, Xavier; Rousseau, Guillaume; Reynolds, Kevin H.

    2016-01-01

    This benchmark experiment was conducted as a joint venture between the US Department of Energy (DOE) and the French Commissariat à l'Energie Atomique (CEA). Staff at the Oak Ridge National Laboratory (ORNL) in the US and the Centre de Valduc in France planned this experiment. The experiment was conducted on October 13, 2010 in the SILENE critical assembly facility at Valduc. Several other organizations contributed to this experiment and the subsequent evaluation, including CEA Saclay, Lawrence Livermore National Laboratory (LLNL), the Y-12 National Security Complex (NSC), Babcock International Group in the United Kingdom, and Los Alamos National Laboratory (LANL). The goal of this experiment was to measure neutron activation and thermoluminescent dosimeter (TLD) doses from a source similar to a fissile solution critical excursion. The resulting benchmark can be used for validation of computer codes and nuclear data libraries as required when performing analysis of criticality accident alarm systems (CAASs). A secondary goal of this experiment was to qualitatively test performance of two CAAS detectors similar to those currently and formerly in use in some US DOE facilities. The detectors tested were the CIDAS MkX and the Rocky Flats NCD-91. The CIDAS detects gammas with a Geiger-Muller tube, and the Rocky Flats detects neutrons via charged particles produced in a thin 6 LiF disc, depositing energy in a Si solid-state detector. These detectors were being evaluated to determine whether they would alarm, so they were not expected to generate benchmark quality data.

  19. Neutron Activation Foil and Thermoluminescent Dosimeter Responses to a Polyethylene Reflected Pulse of the CEA Valduc SILENE Critical Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Thomas Martin [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Celik, Cihangir [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); McMahan, Kimberly L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lee, Yi-kang [French Atomic Energy Commission (CEA), Saclay (France); Gagnier, Emmanuel [French Atomic Energy Commission (CEA), Centre de Saclay, Gif sur Yvette; Authier, Nicolas [French Atomic Energy Commission (CEA), Salives (France). Valduc Centre for Nuclear Studies; Piot, Jerome [French Atomic Energy Commission (CEA), Salives (France). Valduc Centre for Nuclear Studies; Jacquet, Xavier [French Atomic Energy Commission (CEA), Salives (France). Valduc Centre for Nuclear Studies; Rousseau, Guillaume [French Atomic Energy Commission (CEA), Salives (France). Valduc Centre for Nuclear Studies; Reynolds, Kevin H. [Y-12 National Security Complex, Oak Ridge, TN (United States)

    2016-09-01

    This benchmark experiment was conducted as a joint venture between the US Department of Energy (DOE) and the French Commissariat à l'Energie Atomique (CEA). Staff at the Oak Ridge National Laboratory (ORNL) in the US and the Centre de Valduc in France planned this experiment. The experiment was conducted on October 19, 2010 in the SILENE critical assembly facility at Valduc. Several other organizations contributed to this experiment and the subsequent evaluation, including CEA Saclay, Lawrence Livermore National Laboratory (LLNL), the Y-12 National Security Complex (NSC), Babcock International Group in the United Kingdom, and Los Alamos National Laboratory (LANL). The goal of this experiment was to measure neutron activation and thermoluminescent dosimeter (TLD) doses from a source similar to a fissile solution critical excursion. The resulting benchmark can be used for validation of computer codes and nuclear data libraries as required when performing analysis of criticality accident alarm systems (CAASs). A secondary goal of this experiment was to qualitatively test performance of two CAAS detectors similar to those currently and formerly in use in some US DOE facilities. The detectors tested were the CIDAS MkX and the Rocky Flats NCD-91. The CIDAS detects gammas with a Geiger-Muller tube and the Rocky Flats detects neutrons via charged particles produced in a thin 6LiF disc depositing energy in a Si solid state detector. These detectors were being evaluated to determine whether they would alarm, so they were not expected to generate benchmark quality data.

  20. Neutron Activation and Thermoluminescent Detector Responses to a Bare Pulse of the CEA Valduc SILENE Critical Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Thomas Martin [ORNL; Isbell, Kimberly McMahan [ORNL; Lee, Yi-kang [French Atomic Energy Commission (CEA), Centre de Saclay, Gif sur Yvette; Gagnier, Emmanuel [French Atomic Energy Commission (CEA), Centre de Saclay, Gif sur Yvette; Authier, Nicolas [French Atomic Energy Commission (CEA), Centre de Valduc, Is-sur-Tille; Piot, Jerome [French Atomic Energy Commission (CEA), Centre de Valduc, Is-sur-Tille; Jacquet, Xavier [French Atomic Energy Commission (CEA), Centre de Valduc, Is-sur-Tille; Rousseau, Guillaume [French Atomic Energy Commission (CEA), Centre de Valduc, Is-sur-Tille; Reynolds, Kevin H. [Y-12 National Security Complex

    2016-09-01

    This benchmark experiment was conducted as a joint venture between the US Department of Energy (DOE) and the French Commissariat à l'Energie Atomique (CEA). Staff at the Oak Ridge National Laboratory (ORNL) in the US and the Centre de Valduc in France planned this experiment. The experiment was conducted on October 11, 2010 in the SILENE critical assembly facility at Valduc. Several other organizations contributed to this experiment and the subsequent evaluation, including CEA Saclay, Lawrence Livermore National Laboratory (LLNL), the Y-12 National Security Complex (NSC), Babcock International Group in the United Kingdom, and Los Alamos National Laboratory (LANL). The goal of this experiment was to measure neutron activation and thermoluminescent dosimeter (TLD) doses from a source similar to a fissile solution critical excursion. The resulting benchmark can be used for validation of computer codes and nuclear data libraries as required when performing analysis of criticality accident alarm systems (CAASs). A secondary goal of this experiment was to qualitatively test performance of two CAAS detectors similar to those currently and formerly in use in some US DOE facilities. The detectors tested were the CIDAS MkX and the Rocky Flats NCD-91. These detectors were being evaluated to determine whether they would alarm, so they were not expected to generate benchmark quality data.

  1. Neutron Activation Foil and Thermoluminescent Dosimeter Responses to a Polyethylene Reflected Pulse of the CEA Valduc SILENE Critical Assembly

    International Nuclear Information System (INIS)

    Miller, Thomas Martin; Celik, Cihangir; McMahan, Kimberly L.; Lee, Yi-kang; Gagnier, Emmanuel; Authier, Nicolas

    2016-01-01

    This benchmark experiment was conducted as a joint venture between the US Department of Energy (DOE) and the French Commissariat à l'Energie Atomique (CEA). Staff at the Oak Ridge National Laboratory (ORNL) in the US and the Centre de Valduc in France planned this experiment. The experiment was conducted on October 19, 2010 in the SILENE critical assembly facility at Valduc. Several other organizations contributed to this experiment and the subsequent evaluation, including CEA Saclay, Lawrence Livermore National Laboratory (LLNL), the Y-12 National Security Complex (NSC), Babcock International Group in the United Kingdom, and Los Alamos National Laboratory (LANL). The goal of this experiment was to measure neutron activation and thermoluminescent dosimeter (TLD) doses from a source similar to a fissile solution critical excursion. The resulting benchmark can be used for validation of computer codes and nuclear data libraries as required when performing analysis of criticality accident alarm systems (CAASs). A secondary goal of this experiment was to qualitatively test performance of two CAAS detectors similar to those currently and formerly in use in some US DOE facilities. The detectors tested were the CIDAS MkX and the Rocky Flats NCD-91. The CIDAS detects gammas with a Geiger-Muller tube and the Rocky Flats detects neutrons via charged particles produced in a thin "6LiF disc depositing energy in a Si solid state detector. These detectors were being evaluated to determine whether they would alarm, so they were not expected to generate benchmark quality data.

  2. Secondary associations in ‘Himalayan pink’ (Dianthus angulatus Royle ex Benth., Caryophyllaceae from cold deserts of Lahaul-Spiti

    Directory of Open Access Journals (Sweden)

    Kumar Puneet

    2017-01-01

    Full Text Available In current investigation we studied the male meiosis and details of secondary chromosomal associations or pairing recorded for the first time in Dianthus angulatus Royle ex Benth., from the cold deserts of Lahaul-Spiti (Himachal Pradesh, India. All the presently studied individuals of the species existed at 2x level (x = 15. The present chromosome count of n = 15 in the species is in conformity with the previous counts from India and outside of India. Secondary associations are defined as the affinity of bivalents to be positioned in pairs having gentle connections. The secondary chromosomal associations in the species existed among bivalents/chromosomes were observed in the meiocytes at metaphase-I and continued till the metaphase-II. The bivalents positioned side by side and end to end to form secondary pairing. The difference in the number of bivalents/chromosomes involved in the secondary associations has also been witnessed. A secondary association between bivalents is considered to be of immense importance as it is being taken as a gauge of ploidy in plants. The incidence of such secondary associations of bivalents/chromosomes in D. angulatus which existed at 2x level indicated the secondary polyploid nature of the species.

  3. Evaluation of the concrete shield compositions from the 2010 criticality accident alarm system benchmark experiments at the CEA Valduc SILENE facility

    International Nuclear Information System (INIS)

    Miller, Thomas Martin; Celik, Cihangir; Dunn, Michael E; Wagner, John C; McMahan, Kimberly L; Authier, Nicolas; Jacquet, Xavier; Rousseau, Guillaume; Wolff, Herve; Savanier, Laurence; Baclet, Nathalie; Lee, Yi-kang; Trama, Jean-Christophe; Masse, Veronique; Gagnier, Emmanuel; Naury, Sylvie; Blanc-Tranchant, Patrick; Hunter, Richard; Kim, Soon; Dulik, George Michael; Reynolds, Kevin H.

    2015-01-01

    In October 2010, a series of benchmark experiments were conducted at the French Commissariat a l'Energie Atomique et aux Energies Alternatives (CEA) Valduc SILENE facility. These experiments were a joint effort between the United States Department of Energy Nuclear Criticality Safety Program and the CEA. The purpose of these experiments was to create three benchmarks for the verification and validation of radiation transport codes and evaluated nuclear data used in the analysis of criticality accident alarm systems. This series of experiments consisted of three single-pulsed experiments with the SILENE reactor. For the first experiment, the reactor was bare (unshielded), whereas in the second and third experiments, it was shielded by lead and polyethylene, respectively. The polyethylene shield of the third experiment had a cadmium liner on its internal and external surfaces, which vertically was located near the fuel region of SILENE. During each experiment, several neutron activation foils and thermoluminescent dosimeters (TLDs) were placed around the reactor. Nearly half of the foils and TLDs had additional high-density magnetite concrete, high-density barite concrete, standard concrete, and/or BoroBond shields. CEA Saclay provided all the concrete, and the US Y-12 National Security Complex provided the BoroBond. Measurement data from the experiments were published at the 2011 International Conference on Nuclear Criticality (ICNC 2011) and the 2013 Nuclear Criticality Safety Division (NCSD 2013) topical meeting. Preliminary computational results for the first experiment were presented in the ICNC 2011 paper, which showed poor agreement between the computational results and the measured values of the foils shielded by concrete. Recently the hydrogen content, boron content, and density of these concrete shields were further investigated within the constraints of the previously available data. New computational results for the first experiment are now available

  4. Notes on Alcyonidium erectum Silen, 1942 (Ectoprocta) from the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Menon, N.R.

    Seventy new species were recorded during the study of the ectoproctous bryozoans of Indian waters Of these Alcyonidium erectum is of special interest Several zoaria of A erectum were collected from the appendages and carapace of Portunus pelagicus...

  5. Fungal Infection Induces Sex-Specific Transcriptional Changes and Alters Sexual Dimorphism in the Dioecious Plant Silene latifolia.

    Directory of Open Access Journals (Sweden)

    Niklaus Zemp

    2015-10-01

    Full Text Available Sexual dimorphism, including differences in morphology, behavior and physiology between females and males, is widespread in animals and plants and is shaped by gene expression differences between the sexes. Such expression differences may also underlie sex-specific responses of hosts to pathogen infections, most notably when pathogens induce partial sex reversal in infected hosts. The genetic changes associated with sex-specific responses to pathogen infections on the one hand, and sexual dimorphism on the other hand, remain poorly understood. The dioecious White Campion (Silene latifolia displays sexual dimorphism in floral traits and infection with the smut fungus Micobrotryum lychnidis-dioicae induces a partial sex reversal in females. We find strong sex-specific responses to pathogen infection and reduced sexual dimorphism in infected S. latifolia. This provides a direct link between pathogen-mediated changes in sex-biased gene expression and altered sexual dimorphism in the host. Expression changes following infection affected mainly genes with male-biased expression in healthy plants. In females, these genes were up-regulated, leading to a masculinization of the transcriptome. In contrast, infection in males was associated with down-regulation of these genes, leading to a demasculinization of the transcriptome. To a lesser extent, genes with female-biased expression in healthy plants were also affected in opposite directions in the two sexes. These genes were overall down-regulated in females and up-regulated in males, causing, respectively, a defeminization in infected females and a feminization of the transcriptome in infected males. Our results reveal strong sex-specific responses to pathogen infection in a dioecious plant and provide a link between pathogen-induced changes in sex-biased gene expression and sexual dimorphism.

  6. Fungal Infection Induces Sex-Specific Transcriptional Changes and Alters Sexual Dimorphism in the Dioecious Plant Silene latifolia.

    Science.gov (United States)

    Zemp, Niklaus; Tavares, Raquel; Widmer, Alex

    2015-10-01

    Sexual dimorphism, including differences in morphology, behavior and physiology between females and males, is widespread in animals and plants and is shaped by gene expression differences between the sexes. Such expression differences may also underlie sex-specific responses of hosts to pathogen infections, most notably when pathogens induce partial sex reversal in infected hosts. The genetic changes associated with sex-specific responses to pathogen infections on the one hand, and sexual dimorphism on the other hand, remain poorly understood. The dioecious White Campion (Silene latifolia) displays sexual dimorphism in floral traits and infection with the smut fungus Micobrotryum lychnidis-dioicae induces a partial sex reversal in females. We find strong sex-specific responses to pathogen infection and reduced sexual dimorphism in infected S. latifolia. This provides a direct link between pathogen-mediated changes in sex-biased gene expression and altered sexual dimorphism in the host. Expression changes following infection affected mainly genes with male-biased expression in healthy plants. In females, these genes were up-regulated, leading to a masculinization of the transcriptome. In contrast, infection in males was associated with down-regulation of these genes, leading to a demasculinization of the transcriptome. To a lesser extent, genes with female-biased expression in healthy plants were also affected in opposite directions in the two sexes. These genes were overall down-regulated in females and up-regulated in males, causing, respectively, a defeminization in infected females and a feminization of the transcriptome in infected males. Our results reveal strong sex-specific responses to pathogen infection in a dioecious plant and provide a link between pathogen-induced changes in sex-biased gene expression and sexual dimorphism.

  7. Spatial expression dynamics of Men-9 delineate the third floral whorl in male and female flowers of dioecious Silene latifolia.

    Science.gov (United States)

    Robertson, S E; Li, Y; Scutt, C P; Willis, M E; Gilmartin, P M

    1997-07-01

    Sex determination in Silene latifolia is controlled by heteromorphic sex chromosomes. Female flowers have five fused carpels and ten arrested stamen primordia. The male-determining Y chromosome overrides female development to suppress carpel formation and promote stamen development. The isolation and characterization of two S. latifolia. Male enhanced cDNAs, Men-9a and Men-9b, which probably represent different alleles of a novel gene are reported here. Men-9a and Men-9b share 91.8% coding sequence nucleotide identity, yet only 85.4% amino acid identity. The Men-9 cDNAs are related to the previously reported MROS3 cDNA from S. latifolia. However, MROS3 is not present in the S. latifolia population used in these studies and the expression dynamics of Men-9a and Men-9b contrast dramatically with those reported for MROS3. Men-9 cDNAs are expressed primarily in anthers of young male flowers, with highest expression in 1-2 mm buds. Men-9 expression is also observed at a low level in female flowers. In situ hybridization analysis reveals two phases of Men-9 expression. The first phase is during a common stage of early stamen development in male and female flowers prior to stamen arrest in female flowers. The second phase of Men-9 expression is maximal in the epidermis and endothecium of Y chromosome- and Ustilago violacea-induced stamens; expression in male and female flowers extends to the epidermis of the staminal nectaries with strict boundaries at the second and fourth whorls, Men-9 gene expression therefore delineates the boundaries of the third floral whorl in S. latifolia flowers.

  8. Substitution rates in the X- and Y-linked genes of the plants, Silene latifolia and S. dioica.

    Science.gov (United States)

    Filatov, Dmitry A; Charlesworth, Deborah

    2002-06-01

    Theory predicts that selection should be less effective in the nonrecombining genes of Y-chromosomes, relative to the situation for genes on the other chromosomes, and this should lead to the accumulation of deleterious nonsynonymous substitutions. In addition, synonymous substitution rates may differ between X- and Y-linked genes because of the male-driven evolution effect and also because of actual differences in per-replication mutation rates between the sex chromosomes. Here, we report the first study of synonymous and nonsynonymous substitution rates on plant sex chromosomes. We sequenced two pairs of sex-linked genes, SlX1-SlY1 and SlX4-SlY4, from dioecious Silene latifolia and S. dioica, and their non-sex-linked homologues from nondioecious S. vulgaris and Lychnis flos-jovis, respectively. The rate of nonsynonymous substitutions in the SlY4 gene is significantly higher than that in the SlX4 gene. Silent substitution rates are also significantly higher in both Y-linked genes, compared with their X-linked homologues. The higher nonsynonymous substitution rate in the SlY4 gene is therefore likely to be caused by a mutation rate difference between the sex chromosomes. The difference in silent substitution rates between the SlX4 and SlY4 genes is too great to be explained solely by a higher per-generation mutation rate in males than females. It is thus probably caused by a difference in per-replication mutation rates between the sex chromosomes. This suggests that the local mutation rate can change in a relatively short evolutionary time.

  9. Neutron Activation Foil and Thermoluminescent Dosimeter Responses to a Lead Reflected Pulse of the CEA Valduc SILENE Critical Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Thomas Martin [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Celik, Cihangir [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Isbell, Kimberly McMahan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lee, Yi-kang [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA-Saclay), Gif-sur-Yvette (France); Gagnier, Emmanuel [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA-Saclay), Gif-sur-Yvette (France); Authier, Nicolas [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA-Saclay), Gif-sur-Yvette (France); Piot, Jerome [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA-Saclay), Gif-sur-Yvette (France); Jacquet, Xavier [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA-Saclay), Gif-sur-Yvette (France); Rousseau, Guillaume [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA-Saclay), Gif-sur-Yvette (France); Reynolds, Kevin H. [Y-12 National Security Complex, Oak Ridge, TN (United States)

    2016-09-01

    This benchmark experiment was conducted as a joint venture between the US Department of Energy (DOE) and the French Commissariat à l'Energie Atomique (CEA). Staff at the Oak Ridge National Laboratory (ORNL) in the US and the Centre de Valduc in France planned this experiment. The experiment was conducted on October 13, 2010 in the SILENE critical assembly facility at Valduc. Several other organizations contributed to this experiment and the subsequent evaluation, including CEA Saclay, Lawrence Livermore National Laboratory (LLNL), the Y-12 National Security Complex (NSC), Babcock International Group in the United Kingdom, and Los Alamos National Laboratory (LANL). The goal of this experiment was to measure neutron activation and thermoluminescent dosimeter (TLD) doses from a source similar to a fissile solution critical excursion. The resulting benchmark can be used for validation of computer codes and nuclear data libraries as required when performing analysis of criticality accident alarm systems (CAASs). A secondary goal of this experiment was to qualitatively test performance of two CAAS detectors similar to those currently and formerly in use in some US DOE facilities. The detectors tested were the CIDAS MkX and the Rocky Flats NCD-91. The CIDAS detects gammas with a Geiger-Muller tube, and the Rocky Flats detects neutrons via charged particles produced in a thin 6LiF disc, depositing energy in a Si solid-state detector. These detectors were being evaluated to determine whether they would alarm, so they were not expected to generate benchmark quality data.

  10. High-level Zn and Cd tolerance in Silene paradoxa L. from a moderately Cd- and Zn-contaminated copper mine tailing

    International Nuclear Information System (INIS)

    Arnetoli, Miluscia; Vooijs, Riet; Gonnelli, Cristina; Gabbrielli, Roberto; Verkleij, Jos A.C.; Schat, Henk

    2008-01-01

    Cadmium and zinc tolerance were examined in populations of Silene paradoxa, one from uncontaminated calcareous soil (CVD) and one from a mine tailing (FC) (Cd < 1-15 ppm, Zn 400-1300 ppm, pH 2-6). The mine population exhibited extremely high Zn and Cd tolerance levels, although the degrees of Cd and Zn enrichment relatively low at the population site. Cd and Zn hypertolerance in FC were associated with reduced rates of accumulation of these metals, both in roots and shoots (Cd), or exclusively in shoots (Zn). However, exclusion potentially explained only a minor part of the superior tolerance in FC. Cd hypertolerance in FC was associated with decreased, rather than enhanced phytochelatin accumulation. The remarkably high levels of Cd and Zn hypertolerance in FC might relate to the low soil pH, due to oxidation of sulphide minerals, and the absence of soil organic matter at the FC site. - Silene paradoxa from a copper mine exhibits extreme levels of Zn and Cd tolerance

  11. Salvadorianae. III. Una descripció prelinneana de Silene niceensis All., deguda a Jaume Salvador i Pedrol, a l'edició de 1686 del Botanicum Monspeliense de Pèire Magnol

    Directory of Open Access Journals (Sweden)

    Camarasa, Josep M.

    2000-12-01

    Full Text Available Silene niceensis All. (Cariophillaceae is a plant found on litoral sands of Western Mediterranian and also of Iberian Atlantic shores from Gibraltar to the Rias Baixas and in some places in Greece. It had been described twice in prelinnean times but Linné has neglected it in his works. First prelinnean description, though published by Pierre Magnol in the Appedix to the second edition (1686 of Botanicum monspeliense,has been wrote on the basis of materials and a short description sent to Magnol by Jaume Salvador i Pedrol. One specimen of this plant in Salvador Herbarium hold a short description that could be the original one by Jaume Salvador. The second one was published on a different name by Tournefort in Institutiones Rei herbariae. It is also one specimen of S. niceensisAll. in Salvador Herbarium under this identity. Pourret, studying this herbarium to put on etiquets the linnean name of each specimen (1792-98, realize the specific identity of both S. niceensis All. specimens but ignoring the description published by Allioni in 1773 he give them the new name of S. arenaria Pourr. Also Desfontaines described under the name of S. arenaria Desf. in his Flora Atlantica (1798-99 the same species on the basis of specimens collected near the Gibraltar Strait. Both. Pourrett and Desfontaines names, or today invalid and under sinonimy.

    La cariofil làcia Silene niceensis All. pròpia dels sorrats litorals de la Mediterrània occidental i present també a les costes atlàntiques ibèriques. des de l' estret de Gibraltar fins a les Rias Baixas i en alguna localitat grega, havia estar descrita al menys dues vegades temps prelinneans malgrat que Linné mateix la ignorés a les seves obres. La primera descripció prelinneana. bé que publicada por Péire Magnol a l’apèndix a la segona edició del seu Botanicum monspeliense,. es feu sobre la base de materials i fins i tot d

  12. Ultraviolet-B (280-320 nm) absorbing pigments in the leaves of Silene vulgaris: their role in UV-B tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Staaij, J.W.M. van de; Ernst, W. H.O.; Hakvoort, H. W.J.; Rozema, J. [Vrije Univ., Amsterdam (Netherlands)

    1995-07-01

    The UV-B radiation tolerant perennial herb Silene vulgaris was tested on the influence of incident UV-B fluxes during growth on the synthesis of UV-B absorbing pigments in the leaves. Analysis of methanolic leaf extracts showed a stimulating effect of UV-B on the absorbing ability of leaf extracts. HPLC analysis made clear that UV-B radiation stimulated extractable flavonoid concentrations in leaves, but that UV-B absorption could only be partly attributed to these flavonoids. The contribution of flavonoids to UV-B absorption diminishes if plants mature. Other possible functions of flavonoids in plants growing under elevated UV-B conditions are discussed. (author)

  13. Ultraviolet-B (280-320 nm) absorbing pigments in the leaves of Silene vulgaris: their role in UV-B tolerance

    International Nuclear Information System (INIS)

    Staaij, J.W.M. van de; Ernst, W.H.O.; Hakvoort, H.W.J.; Rozema, J.

    1995-01-01

    The UV-B radiation tolerant perennial herb Silene vulgaris was tested on the influence of incident UV-B fluxes during growth on the synthesis of UV-B absorbing pigments in the leaves. Analysis of methanolic leaf extracts showed a stimulating effect of UV-B on the absorbing ability of leaf extracts. HPLC analysis made clear that UV-B radiation stimulated extractable flavonoid concentrations in leaves, but that UV-B absorption could only be partly attributed to these flavonoids. The contribution of flavonoids to UV-B absorption diminishes if plants mature. Other possible functions of flavonoids in plants growing under elevated UV-B conditions are discussed. (author)

  14. Unparalleled rates of species diversification in Europe

    Science.gov (United States)

    Valente, Luis M.; Savolainen, Vincent; Vargas, Pablo

    2010-01-01

    The most rapid species radiations have been reported from ‘evolutionary laboratories’, such as the Andes and the Cape of South Africa, leading to the prevailing view that diversification elsewhere has not been as dramatic. However, few studies have explicitly assessed rates of diversification in northern regions such as Europe. Here, we show that carnations (Dianthus, Caryophyllaceae), a well-known group of plants from temperate Eurasia, have diversified at the most rapid rate ever reported in plants or terrestrial vertebrates. Using phylogenetic methods, we found that the majority of species of carnations belong to a lineage that is remarkably species-rich in Europe, and arose at the rate of 2.2–7.6 species per million years. Unlike most previous studies that have inferred rates of diversification in young diverse groups, we use a conservative approach throughout that explicitly incorporates the uncertainties associated with phylogenetic inference, molecular dating and incomplete taxon sampling. We detected a shift in diversification rates of carnations coinciding with a period of increase in climatic aridity in the Pleistocene, suggesting a link between climate and biodiversity. This explosive radiation suggests that Europe, the continent with the world's best-studied flora, has been underestimated as a cradle of recent and rapid speciation. PMID:20106850

  15. Semi-automatic laser beam microdissection of the Y chromosome and analysis of Y chromosome DNA in a dioecious plant, Silene latifolia

    International Nuclear Information System (INIS)

    Matsunaga, S.; Kawano, S.; Michimoto, T.; Higashiyama, T.; Nakao, S.; Sakai, A.; Kuroiwa, T.

    1999-01-01

    Silene latifolia has heteromorphic sex chromosomes, the X and Y chromosomes. The Y chromosome, which is thought to carry the male determining gene, was isolated by UV laser microdissection and amplified by degenerate oligonucleotide-primed PCR. In situ chromosome suppression of the amplified Y chromosome DNA in the presence of female genomic DNA as a competitor showed that the microdissected Y chromosome DNA did not specifically hybridize to the Y chromosome, but-hybridized to all chromosomes. This result suggests that the Y chromosome does not contain Y chromosome-enriched repetitive sequences. A repetitive sequence in the microdissected Y chromosome, RMY1, was isolated while screening repetitive sequences in the amplified Y chromosome. Part of the nucleotide sequence shared a similarity to that of X-43.1, which was isolated from microdissected X chromosomes. Since fluorescence in situ hybridization analysis with RMY1 demonstrated that RMY1 was localized at the ends of the chromosome, RMY1 may be a subtelomeric repetitive sequence. Regarding the sex chromosomes, RMY1 was detected at both ends of the X chromosome and at one end near the pseudoautosomal region of the Y chromosome. The different localization of RMY1 on the sex chromosomes provides a clue to the problem of how the sex chromosomes arose from autosomes

  16. Criticality accidents in solution (CRAC and SILENE programmes) and complementary studies of accidents; radiation dosimetry in human organism during the CRAC programme

    International Nuclear Information System (INIS)

    Barbry, M.; Dousset, M.

    C.R.A.C. (CRiticality occurring ACcidentally) programme is intended to study experimentally the development of a criticality accident as it could occur when handling solutions of fissile material as well as the radiological consequences of such an accident. The fissile matter solutions have been chosen (a) for practical considerations of use and (b) because the probability of an accident occurring seems greater with this type of environment, as the known accidents have shown. The programme is twofold: study of accident physics: form of the evolution (peak, plateau, oscillations, boil up of solutions) the most probable maximum power, minimal power, flux and radiation spectra emitted, freed energy, associated effects, radiolysis, constraints, etc., study of radiological consequences: area dosimetry, individual dosimetry, radiobiological studies, etc. Additional criticality Accident experiments have been and continue to be made on the SILENE reactor in the following principal domains: determination of the emission rate of gaseous fission products and aerosols, area dosimetry and health dosimetry in the presence of shields around the core to vary the neutron and gamma components of the radiation field. Improvement in the knowledge of certain particular aspects of the power excursion, radiolysis gas and pressure wave, experiments of the ''boiling'' type [fr

  17. [Differentiation of species of Bupleurum and its changes].

    Science.gov (United States)

    Zhao, Bao-Lin

    2013-07-01

    Bupleurum is originated from the genus of Bupleurum chinensis DC of Umbelliferae. In China, the species of bupleurum for medicinal used are very complicate. During the Han-Tang Dynasties the bupleurum used covered a variety of its genera from Umbelliferae. "Yinzhou bupleurum" is the most famous in the Song Dynasty. Due to the continuous deterioration of its growing environment, the resources of the wild species of Yinzhou Bupleurum was declined, hence, those grown in other locations gradually attracted people's interests. Bupleutum was differentiated as Northern and Southern ones in the Ming Dynasty based on its different properties. Similar in its morphology and growing location to the Yinzhou Bupleurum, the Stellaria dichotoma lanceolata of the Caryophyllaceae was used as a substitute for the former. However, due to its prominent medicinal effects different from the Yinzhou one, the latter was continuously applied as a new herb. There are 2 great varieties of bupleurum used in modern times, the Bupleurum chinensis DC, and the Bupleurm scorzonerifolium Willd. Since the species of bupleurum in the current market are very complicate, and its clinical applications are quite confused, standardization and strengthening of its research are badly needed so as to promote its marketing.

  18. Swelling and Degradation of Calcium-Pectic Gel Particles Made of Pectins of Silene vulgaris and Lemna minor Сallus Cultures at Different Concentrations of Pectinase in an Artificial Colon Environment

    Directory of Open Access Journals (Sweden)

    Anatoly A. Shubakov

    2018-03-01

    Full Text Available Spherical calcium-pectic gel particles (CaPGPs were obtained from pectins of callus cultures (CC of campion Silene vulgaris (silenan and duckweed Lemna minor (lemnan, as well as from commercial apple and citrus pectins by the method of ionotropic gelation. We studied the morphological characteristics of the obtained gel particles and found that the largest gel particles were formed from citrus pectin (CP, and the densest gel particles were formed from lemnan pectin (LP. The swelling and degradation of CaPGPs were comparatively evaluated by incubation in a simulated gastrointestinal environment. The swelling and degradation of CaPGPs formed from pectins of the silenan and lemnan callus cultures were studied at different concentrations of pectinase (0.4, 0.8 and 1.7 mg/ml in the simulated fluid of the colon. It has been established that the CaPGPs obtained from lemnan are more resistant to degradation in the simulated colon fluid than CaPGP obtained from silenan. It was shown that the concentration of pectinase in the simulated fluid of the colon and the type of pectin affect the degradability of CaPGPs formed on the basis of pectins of callus cultures.

  19. Multifunctionality is affected by interactions between green roof plant species, substrate depth, and substrate type.

    Science.gov (United States)

    Dusza, Yann; Barot, Sébastien; Kraepiel, Yvan; Lata, Jean-Christophe; Abbadie, Luc; Raynaud, Xavier

    2017-04-01

    Green roofs provide ecosystem services through evapotranspiration and nutrient cycling that depend, among others, on plant species, substrate type, and substrate depth. However, no study has assessed thoroughly how interactions between these factors alter ecosystem functions and multifunctionality of green roofs. We simulated some green roof conditions in a pot experiment. We planted 20 plant species from 10 genera and five families (Asteraceae, Caryophyllaceae, Crassulaceae, Fabaceae, and Poaceae) on two substrate types (natural vs. artificial) and two substrate depths (10 cm vs. 30 cm). As indicators of major ecosystem functions, we measured aboveground and belowground biomasses, foliar nitrogen and carbon content, foliar transpiration, substrate water retention, and dissolved organic carbon and nitrates in leachates. Interactions between substrate type and depth strongly affected ecosystem functions. Biomass production was increased in the artificial substrate and deeper substrates, as was water retention in most cases. In contrast, dissolved organic carbon leaching was higher in the artificial substrates. Except for the Fabaceae species, nitrate leaching was reduced in deep, natural soils. The highest transpiration rates were associated with natural soils. All functions were modulated by plant families or species. Plant effects differed according to the observed function and the type and depth of the substrate. Fabaceae species grown on natural soils had the most noticeable patterns, allowing high biomass production and high water retention but also high nitrate leaching from deep pots. No single combination of factors enhanced simultaneously all studied ecosystem functions, highlighting that soil-plant interactions induce trade-offs between ecosystem functions. Substrate type and depth interactions are major drivers for green roof multifunctionality.

  20. Both life-history plasticity and local adaptation will shape range-wide responses to climate warming in the tundra plant Silene acaulis.

    Science.gov (United States)

    Peterson, Megan L; Doak, Daniel F; Morris, William F

    2018-04-01

    Many predictions of how climate change will impact biodiversity have focused on range shifts using species-wide climate tolerances, an approach that ignores the demographic mechanisms that enable species to attain broad geographic distributions. But these mechanisms matter, as responses to climate change could fundamentally differ depending on the contributions of life-history plasticity vs. local adaptation to species-wide climate tolerances. In particular, if local adaptation to climate is strong, populations across a species' range-not only those at the trailing range edge-could decline sharply with global climate change. Indeed, faster rates of climate change in many high latitude regions could combine with local adaptation to generate sharper declines well away from trailing edges. Combining 15 years of demographic data from field populations across North America with growth chamber warming experiments, we show that growth and survival in a widespread tundra plant show compensatory responses to warming throughout the species' latitudinal range, buffering overall performance across a range of temperatures. However, populations also differ in their temperature responses, consistent with adaptation to local climate, especially growing season temperature. In particular, warming begins to negatively impact plant growth at cooler temperatures for plants from colder, northern populations than for those from warmer, southern populations, both in the field and in growth chambers. Furthermore, the individuals and maternal families with the fastest growth also have the lowest water use efficiency at all temperatures, suggesting that a trade-off between growth and water use efficiency could further constrain responses to forecasted warming and drying. Taken together, these results suggest that populations throughout species' ranges could be at risk of decline with continued climate change, and that the focus on trailing edge populations risks overlooking the largest

  1. Endangered Species

    Science.gov (United States)

    EPA's Endangered Species Protection Program helps promote recovery of listed species. The ESPP determines if pesticide use in a geographic area may affect any listed species. Find needed limits on pesticide use in Endangered Species Protection Bulletins.

  2. Immatures of Palaearctic species of the weevil genus Sibinia (Coleoptera, Curculionidae): new descriptions and new bionomic data with suggestions on their potential value in a phylogenetic reconstruction of the genus.

    Science.gov (United States)

    Skuhrovec, Jiří; Gosik, Rafał; Caldara, Roberto; Košťál, Michael

    2015-05-04

    The larvae and pupae of six species of the Palaearctic genus Sibinia Germar, 1817 are described in detail for the first time. Five of them develop in seeds of Caryophyllaceae and belong to Sibinia (s. str.): S. attalica Gyllenhal, 1835; S. femoralis Germar, 1824; S. tibialis Gyllenhal, 1835; and S. viscariae (Linnaeus, 1760), which are included in the S. femoralis group, and S. sicana Ragusa, 1908, which is included in the S. unicolor Fåhraeus, 1843 group. The sixth species is S. sodalis Germar, 1824, which develops in seeds of Plumbaginaceae and belongs to the subgenus Dichotychius Bedel, 1885. The larvae and pupae of these species are compared with those previously described for some species of the third subgenus, Microtychius Casey, 1910 from the Americas. Some larval characters, but no pupal ones, are useful to support the three subgenera and the two previously mentioned groups of Sibinia s. str., which were previously postulated based on a few adult morphological characters. The immatures of Sibinia are also compared with those of the closely related genus Tychius Germar, 1817, providing some distinctive characters between both genera. New bionomic data on larval and pupal development and adult emergence are reported for all the described species. These data suggest that species in this genus are highly homogeneous in life history traits.

  3. Testing the Stress-Gradient Hypothesis at the Roof of the World: Effects of the Cushion Plant Thylacospermum caespitosum on Species Assemblages

    Science.gov (United States)

    Dvorský, Miroslav; Doležal, Jiří; Kopecký, Martin; Chlumská, Zuzana; Janatková, Kateřina; Altman, Jan; de Bello, Francesco; Řeháková, Klára

    2013-01-01

    Many cushion plants ameliorate the harsh environment they inhabit in alpine ecosystems and act as nurse plants, with significantly more species growing within their canopy than outside. These facilitative interactions seem to increase with the abiotic stress, thus supporting the stress-gradient hypothesis. We tested this prediction by exploring the association pattern of vascular plants with the dominant cushion plant Thylacospermum caespitosum (Caryophyllaceae) in the arid Trans-Himalaya, where vascular plants occur at one of the highest worldwide elevational limits. We compared plant composition between 1112 pair-plots placed both inside cushions and in surrounding open areas, in communities from cold steppes to subnival zones along two elevational gradients (East Karakoram: 4850–5250 m and Little Tibet: 5350–5850 m). We used PERMANOVA to assess differences in species composition, Friedman-based permutation tests to determine individual species habitat preferences, species-area curves to assess whether interactions are size-dependent and competitive intensity and importance indices to evaluate plant-plant interactions. No indications for net facilitation were found along the elevation gradients. The open areas were not only richer in species, but not a single species preferred to grow exclusively inside cushions, while 39–60% of 56 species detected had a significant preference for the habitat outside cushions. Across the entire elevation range of T. caespitosum, the number and abundance of species were greater outside cushions, suggesting that competitive rather than facilitative interactions prevail. This was supported by lower soil nutrient contents inside cushions, indicating a resource preemption, and little thermal amelioration at the extreme end of the elevational gradient. We attribute the negative associations to competition for limited resources, a strong environmental filter in arid high-mountain environment selecting the stress-tolerant species

  4. Testing the stress-gradient hypothesis at the roof of the world: effects of the cushion plant Thylacospermum caespitosum on species assemblages.

    Directory of Open Access Journals (Sweden)

    Miroslav Dvorský

    Full Text Available Many cushion plants ameliorate the harsh environment they inhabit in alpine ecosystems and act as nurse plants, with significantly more species growing within their canopy than outside. These facilitative interactions seem to increase with the abiotic stress, thus supporting the stress-gradient hypothesis. We tested this prediction by exploring the association pattern of vascular plants with the dominant cushion plant Thylacospermum caespitosum (Caryophyllaceae in the arid Trans-Himalaya, where vascular plants occur at one of the highest worldwide elevational limits. We compared plant composition between 1112 pair-plots placed both inside cushions and in surrounding open areas, in communities from cold steppes to subnival zones along two elevational gradients (East Karakoram: 4850-5250 m and Little Tibet: 5350-5850 m. We used PERMANOVA to assess differences in species composition, Friedman-based permutation tests to determine individual species habitat preferences, species-area curves to assess whether interactions are size-dependent and competitive intensity and importance indices to evaluate plant-plant interactions. No indications for net facilitation were found along the elevation gradients. The open areas were not only richer in species, but not a single species preferred to grow exclusively inside cushions, while 39-60% of 56 species detected had a significant preference for the habitat outside cushions. Across the entire elevation range of T. caespitosum, the number and abundance of species were greater outside cushions, suggesting that competitive rather than facilitative interactions prevail. This was supported by lower soil nutrient contents inside cushions, indicating a resource preemption, and little thermal amelioration at the extreme end of the elevational gradient. We attribute the negative associations to competition for limited resources, a strong environmental filter in arid high-mountain environment selecting the stress

  5. Pas de deux: An Intricate Dance of Anther Smut and Its Host

    Directory of Open Access Journals (Sweden)

    Su San Toh

    2018-02-01

    Full Text Available The successful interaction between pathogen/parasite and host requires a delicate balance between fitness of the former and survival of the latter. To optimize fitness a parasite/pathogen must effectively create an environment conducive to reproductive success, while simultaneously avoiding or minimizing detrimental host defense response. The association between Microbotryum lychnidis-dioicae and its host Silene latifolia serves as an excellent model to examine such interactions. This fungus is part of a species complex that infects species of the Caryophyllaceae, replacing pollen with the fungal spores. In the current study, transcriptome analyses of the fungus and its host were conducted during discrete stages of bud development so as to identify changes in fungal gene expression that lead to spore development and to identify changes associated with infection in the host plant. In contrast to early biotrophic phase stages of infection for the fungus, the latter stages involve tissue necrosis and in the case of infected female flowers, further changes in the developmental program in which the ovary aborts and a pseudoanther is produced. Transcriptome analysis via Illumina RNA sequencing revealed enrichment of fungal genes encoding small secreted proteins, with hallmarks of effectors and genes found to be relatively unique to the Microbotryum species complex. Host gene expression analyses also identified interesting sets of genes up-regulated, including those involving stress response, host defense response, and several agamous-like MADS-box genes (AGL61 and AGL80, predicted to interact and be involved in male gametophyte development.

  6. SALMONELLA SPECIES

    African Journals Online (AJOL)

    DR. AMINU

    ... of Salmonella species serotypes in relation to age and sex among children, ..... However, most antimicrobials show sufficient selective toxicity to be of value in ... salmonellosis should be given good attention (Barrow et al., 2007). To reduce ...

  7. Podredumbres basales de Gypsophila paniculata (Caryophyllaceae: Agentes causales y su patogenicidad potencial sobre Dianthus caryophyllus (Caryophyllaceae Basal rots of Gypsophila paniculata (Caryophyllaceae: Causal agents and its potential pathogenicity on Dianthus caryophyllus (Caryophyllaceae

    Directory of Open Access Journals (Sweden)

    Silvia María Wolcan

    Full Text Available Los objetivos del trabajo fueron identificar a los agentes causales de las podredumbres basales de Gypsophila paniculata en la Argentina y probar su posible patogenicidad sobre Dianthus caryophyllus . A partir de plantas con síntomas de «podredumbre de la corona» (la más importante se aislaron en orden decreciente: Fusarium solani , F. oxysporum , Phytophthora nicotianae , Rhizoctonia solani , F. graminearum , F. verticillioides, F. equiseti y Pythium sp. y de plantas con «podredumbre basal del tallo» F. graminearum , F. oxysporum y F. solani . Con distintas cepas de cada hongo se hicieron pruebas de patogenicidad mediante la infestación del suelo y el depósito de inóculo en heridas producidas en los tallos. En la «podredumbre de la corona» fueron patógenos P. nicotianae causando decaimiento rápido de la parte aérea y podredumbre blanda de la corona y R. solani causando una pudrición más lenta y tejidos desintegrados. F. graminearum fue el patógeno de la «podredumbre basal del tallo» de gipsofila, que se describe por primera vez en este hospedante , comprobando que el hongo penetra sólo por heridas del tallo. En condiciones de inoculación se confirmó que algunas cepas de R. solani y de F. graminearum aisladas de gipsofila pueden ser patógenas de clavel mientras que sólo algunas de P. nicotianae resultaron patógenas débiles.The aims of the paper were to determine the causal agents of basal rots of Gypsophila paniculata in Argentina, and to evaluate its possible pathogenicity on Dianthus caryophyllus. Fusarium solani, F. oxysporum , Phytophthora nicotianae , Rhizoctonia solani , F. graminearum , F. verticilloides, F. equiseti and Pythium sp. were isolated in decreasing order from plants with symptoms of «crown rot» (the major basal rot. F. graminearum , F. oxysporum and F. solani were isolated from plants with «basal stem rot». Inoculations of gypsophila were performed by soil infestation and by placing inoculum on basal stem wounds with different strains of each fungus. Crown rot was incited by P. nicotianae causing fast decay of leaves and stems and wet soft rot of the crowns, and by R. solani causing slower decay and disintegrated crown tissues. Basal stem rot was incited by F. graminearum , which was described for the first time on G. paniculata and enter through wounded tissues. Under experimental conditions some strains of R. solani and F. graminearum isolated from gipsofila caused stem rot on carnation plants and only some strains of P. niconianae were weakly pathogenic.

  8. Assessing radiation exposure of herbaceous plant species at the East-Ural Radioactive Trace

    International Nuclear Information System (INIS)

    Karimullina, Elina; Antonova, Elena; Pozolotina, Vera

    2013-01-01

    The East-Ural Radioactive Trace (EURT) is a result of the Mayak Production Association accident that occurred in 1957 in Russia. Radiological assessment improves the interpretation of biological effects of exposure to ionizing radiation. Therefore a modeling approach was used to estimate dose rates on Leonurus quinquelobatus, Silene latifolia, Stellaria graminea and Bromus inermis. Soil-to-organism transfer parameter values are delivered from empirical data of 90 Sr and 137 Cs soil and vegetative plant mass activity concentrations. External and internal whole-body dose rates were calculated using deterministic (The ERICA Tool-Tier 2 and R and D 128/SP1a) and probabilistic (The ERICA Tool-Tier 3) methods. The total dose rate for herbs was under 100 μGy h −1 at the most polluted site. The total absorbed dose rates increased 43–110 times (Tier 3) for different herbaceous plant species along the pollution gradient. Based on these data, it can be concluded that herbaceous plant populations currently exist under low-level chronic exposure at the EURT area. -- Highlights: • A modeling approach (The ERICA Tool-Tier 2, Tier 3 and R and D 128/SP1a) was used to estimate dose rates for herbs growing in the wild at the East-Ural Radioactive Trace. • The highest levels of anthropogenic radiation exposure were determined for herbs at Impact EURT sites. • Total absorbed dose rates increased 43–110 times (Tier 3) for different herbaceous plant species along the pollution gradient. • Total dose rate per plant organism for herbs is under 100 μGy h −1 at the most polluted site. Currently herbaceous plant populations exist under low-level chronic exposure at the EURT area

  9. In vitro placental self and cross pollination in some species

    Directory of Open Access Journals (Sweden)

    Azza Shehata

    2014-01-01

    Full Text Available Excised placentae with ovules of Primula pubescens, P. auricula, Scopolia carniolica, Digitalis purpurea, Torenia fournieri and Chionodoxa luciliae were self pollinated in vitro and the development of seeds was observed. The same method was used for obtaining hybrid globular embryos from crosses between: P. pubescens x P. auricula, Scopolia carniolica x Physochlaina praealta, Melandrium album x Silene saxifraga and M. album x Arenaria pungens.

  10. Endangered Species Day | Endangered Species Coalition

    Science.gov (United States)

    Annual Top 10 Report Protecting the Endangered Species Act Wildlife Voices Stand for Wolves Endangered Campaigns Wildlife Voices Protecting the Endangered Species Act Annual Top 10 Report Endangered Species Day Stand for Wolves Vanishing BOOK: A Wild Success The Endangered Species Act at 40 Endangered Species The

  11. Species concept and speciation

    Directory of Open Access Journals (Sweden)

    Amal Y. Aldhebiani

    2018-03-01

    Full Text Available Defining and recognizing a species has been a controversial issue for a long time. To determine the variation and the limitation between species, many concepts have been proposed. When a taxonomist study a particular taxa, he/she must adopted a species concept and provide a species limitation to define this taxa. In this paper some of species concepts are discussed starting from the typological species concepts to the phylogenetic concept. Positive and negative aspects of these concepts are represented in addition to their application. Keywords: Species concept, Species limitation, Species, Taxonomy, Classification

  12. Species accounts. Chapter 4

    Science.gov (United States)

    Margaret K. Trani; W. Mark Ford; Brian R., eds. Chapman

    2007-01-01

    Narrative accounts for each species are presented by several authors in a consistent format to convey specific information relative to that mammal. The orders are arranged phylogenetically; families and species are arranged alphabetically to facilitate finding a particular species.

  13. Regeneration of whole fertile plants from 30,000-y-old fruit tissue buried in Siberian permafrost.

    Science.gov (United States)

    Yashina, Svetlana; Gubin, Stanislav; Maksimovich, Stanislav; Yashina, Alexandra; Gakhova, Edith; Gilichinsky, David

    2012-03-06

    Whole, fertile plants of Silene stenophylla Ledeb. (Caryophyllaceae) have been uniquely regenerated from maternal, immature fruit tissue of Late Pleistocene age using in vitro tissue culture and clonal micropropagation. The fruits were excavated in northeastern Siberia from fossil squirrel burrows buried at a depth of 38 m in undisturbed and never thawed Late Pleistocene permafrost sediments with a temperature of -7 °C. Accelerator mass spectrometry (AMS) radiocarbon dating showed fruits to be 31,800 ± 300 y old. The total γ-radiation dose accumulated by the fruits during this time was calculated as 0.07 kGy; this is the maximal reported dose after which tissues remain viable and seeds still germinate. Regenerated plants were brought to flowering and fruiting and they set viable seeds. At present, plants of S. stenophylla are the most ancient, viable, multicellular, living organisms. Morphophysiological studies comparing regenerated and extant plants obtained from modern seeds of the same species in the same region revealed that they were distinct phenotypes of S. stenophylla. The first generation cultivated from seeds obtained from regenerated plants progressed through all developmental stages and had the same morphological features as parent plants. The investigation showed high cryoresistance of plant placental tissue in permafrost. This natural cryopreservation of plant tissue over many thousands of years demonstrates a role for permafrost as a depository for an ancient gene pool, i.e., preexisting life, which hypothetically has long since vanished from the earth's surface, a potential source of ancient germplasm, and a laboratory for the study of rates of microevolution.

  14. Identification and Initial Characterization of the Effectors of an Anther Smut Fungus and Potential Host Target Proteins

    Directory of Open Access Journals (Sweden)

    Venkata S. Kuppireddy

    2017-11-01

    Full Text Available (1 Background: Plant pathogenic fungi often display high levels of host specificity and biotrophic fungi; in particular, they must manipulate their hosts to avoid detection and to complete their obligate pathogenic lifecycles. One important strategy of such fungi is the secretion of small proteins that serve as effectors in this process. Microbotryum violaceum is a species complex whose members infect members of the Caryophyllaceae; M. lychnidis-dioicae, a parasite on Silene latifolia, is one of the best studied interactions. We are interested in identifying and characterizing effectors of the fungus and possible corresponding host targets; (2 Methods: In silico analysis of the M. lychnidis-dioicae genome and transcriptomes allowed us to predict a pool of small secreted proteins (SSPs with the hallmarks of effectors, including a lack of conserved protein family (PFAM domains and also localized regions of disorder. Putative SSPs were tested for secretion using a yeast secretion trap method. We then used yeast two-hybrid analyses for candidate-secreted effectors to probe a cDNA library from a range of growth conditions of the fungus, including infected plants; (3 Results: Roughly 50 SSPs were identified by in silico analysis. Of these, 4 were studied further and shown to be secreted, as well as examined for potential host interactors. One of the putative effectors, MVLG_01732, was found to interact with Arabidopsis thaliana calcium-dependent lipid binding protein (AtCLB and with cellulose synthase interactive protein 1 orthologues; and (4 Conclusions: The identification of a pool of putative effectors provides a resource for functional characterization of fungal proteins that mediate the delicate interaction between pathogen and host. The candidate targets of effectors, e.g., AtCLB, involved in pollen germination suggest tantalizing insights that could drive future studies.

  15. Agroforestry Species Switchboard

    DEFF Research Database (Denmark)

    Kindt, R.; John, I.; Ordonez, J.

    2016-01-01

    The current version of the Agroforestry Species Switchboard documents the presence of a total of 26,135 plant species (33,813 species including synonyms) across 19 web-based databases. When available, hyperlinks to information on the selected species in particular databases are provided. In total...

  16. Endangered Species Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of the Endangered Species Act (ESA) is to protect and recover imperiled species and the ecosystems upon which they depend. The U.S. Fish and Wildlife...

  17. Endangered Species Protection Bulletins

    Science.gov (United States)

    Endangered Species Protection Bulletins set forth geographically specific pesticide use limitations for the protection of threatened and endangered (listed) species and their designated critical habitat. Find out how to get and use Bulletins.

  18. Smoke-induced seed germination in California chaparral

    Science.gov (United States)

    Keeley, J.E.; Fotheringham, C.J.

    1998-01-01

    The California chaparral community has a rich flora of species with different mechanisms for cuing germination to postfire conditions. Heat shock triggers germination of certain species but has no stimulatory effect on a great many other postfire species that are chemically stimulated by combustion products. Previous reports have shown that charred wood will induce germination, and here we report that smoke also induces germination in these same species. Smoke is highly effective, often inducing 100% germination in deeply dormant seed populations with 0% control germination. Smoke induces germination both directly and indirectly by aqueous or gaseous transfer from soil to seeds. Neither nitrate nor ammonium ions were effective in stimulating germination of smoke-stimulated species, nor were most of the quantitatively important gases generated by biomass smoke. Nitrogen dioxide, however, was very effective at inducing germination in Caulanthus heterophyllus (Brassicaceae), Emmenanthe penduliflora (Hydrophyllaceae), Phacelia grandiflora (Hydrophyllaceae), and Silene multinervia (Caryophyllaceae). Three species, Dendromecon rigida (Papaveraceae), Dicentra chrysantha, and Trichostema lanatum (Lamiaceae), failed to germinate unless smoke treatment was coupled with prior treatment of 1 yr soil storage. Smoke-stimulated germination was found in 25 chaparral species, representing 11 families, none of which were families known for heat-shock-stimulated germination. Seeds of smoke-stimulated species have many analogous characteristics that separate them from most heat-shock-stimulated seeds, including: (1) outer seed coats that are highly textured, (2) a poorly developed outer cuticle, (3) absence of a dense palisade tissue in the seed coat, and (4) a subdermal membrane that is semipermeable, allowing water passage but blocking entry of large (molecular mass > 500) solutes. Tentative evidence suggests that permeability characteristics of this subdermal layer are altered by

  19. Species diversity modulates predation

    NARCIS (Netherlands)

    Kratina, P.; Vos, M.; Anholt, B.R.

    2007-01-01

    Predation occurs in a context defined by both prey and non-prey species. At present it is largely unknown how species diversity in general, and species that are not included in a predator's diet in particular, modify predator–prey interactions.Therefore we studied how both the density and diversity

  20. Species choice, provenance and species trials among native Brazilian species

    Energy Technology Data Exchange (ETDEWEB)

    Drumond, M A

    1982-01-01

    Six papers from the conference are presented. Drumond, M.A., Potential of species native to the semi-arid tropics, 766-781, (Refs. 18), reports on Anadenanthera macrocarpa, Mimosa species, Schinopsis brasiliensis, Spondias tuberosa, Ziziphus joazeiro, Cnidoscolus phyllacanthus, Bursera leptophleos (leptophloeos), Tabebuia impetiginosa, Astronium urundeuva, and Mimosa caesalpinia. Monteiro, R.F.R., Speltz, R.M., Gurgel, J.T. do A.; Silvicultural performance of 24 provenances of Araucaria angustifolia in Parana, 814-824, (Refs. 8). Pires, C.L. da S., Kalil Filho, A.N., Rosa, P.R.F. da, Parente, P.R., Zanatto, A.C.S.; Provenance trials of Cordia alliodora in the State of Sao Paulo, 988-995, (Refs. 9). Nogueira, J.C.B., Siqueira, A.C.M.F., Garrido, M.A.O., Gurgel Garrido, L.M. do A., Rosa, P.R.F., Moraes, J.L. de, Zandarin, M.A., Gurgel Filho, O.A., Trials of some native species in various regions of the State of Sao Paulo, 1051-1063, (Refs. 9) describes Centrolobium tomentosum, Peltophorum dubium, Tabebuia vellosoi, Cariniana legalis, and Balfourodendron riedelianum. Batista, M.P., Borges, J.F., Franco, M.A.B.; Early growth of a native species in comparison with exotics in northeastern Para, Brazil, 1105-1110, (Refs. 3). Jacaranda copaia is compared with Gmelina arborea, Pinus caribaea various hondurensis, Eucalyptus deglupta, and E. urophylla. Lima, P.C.F., Souza, S.M. de, Drumond, M.A.; Trials of native forest species at Petrolina, Pernambuco, 1139-1148, (Refs. 8), deals with Anadenanthera macrocarpa, Piptadenia obliqua, Pithecellobium foliolosum, Astronium urundeuva, Schinopsis brasiliensis, Cassia excelsa, Caesalpinia pyramidalis, Parkia platycephala, Pseudobombax simplicifolium, Tabebuia impetiginosa, Caesalpinia ferrea, and Aspidosperma pyrifolium. 18 references.

  1. Separation of chemical species

    International Nuclear Information System (INIS)

    Rentzepis, P.M.

    1977-01-01

    Isotopic separation is accomplished by (1) a second photon irradiation step for selective ionization of a first isotopic species and (2) selective precipitation of a generally immiscible liquid from the saturating vapor phase on the ionized species. The first photon corresponds with a sharply defined spectral portion of the irradiation which exclusively excites the first species to a vibrational level. The second photon further excites this species to its ionization level. Selective precipitation is by coulombic attraction between the ionized species and the vapor. The procedure is applicable to any vapor phase ionizable material

  2. Phytochemical profiles and antioxidant potential of four Arctic vascular plants from Svalbard

    Digital Repository Service at National Institute of Oceanography (India)

    Singh, P.; Singh, S.M.; DeSouza, L.; Wahidullah, S.

    the chemical composition and antioxidative activities of four Arctic flowering plant species (Dryas octopetala, Carex rupestris, Silene uralensis and Deschampsia alpina.) through in vitro measurements of the free radical scavenging activities (FRS), inhibition...

  3. Detection of cryptic species

    International Nuclear Information System (INIS)

    Cockburn, A.F.; Jensen, T.; Seawright, J.A.

    1998-01-01

    Morphologically similar cryptic species are common in insects. In Anopheles mosquitoes morphologically described species are complexes of cryptic species. Cryptic species are of great practical importance for two reasons: first, one or more species of the complex might not be a pest and control efforts directed at the complex as a whole would therefore be partly wasted; and second, genetic (and perhaps biological) control strategies directed against one species of the complex would not affect other species of the complex. At least one SIT effort has failed because the released sterile insect were of a different species and therefore did not mate with the wild insects being targeted. We use a multidisciplinary approach for detection of cryptic species complexes, focusing first on identifying variability in wild populations using RFLPs of mitochondrial and ribosomal RNA genes (mtDNA and rDNA); followed by confirmation using a variety of other techniques. For rapid identification of wild individuals of field collections, we use a DNA dot blot assay. DNA probes can be isolated by differential screening, however we are currently focusing on the sequencing of the rDNA extragenic spacers. These regions are repeated several hundred times per genome in mosquitoes and evolve rapidly. Molecular drive tends to keen the individual genes homogeneous within a species. (author)

  4. Detection of cryptic species

    Energy Technology Data Exchange (ETDEWEB)

    Cockburn, A F; Jensen, T; Seawright, J A [United States Dept. of Agriculture, Agricultural Research Service, Medical and Veterinary Entomology Research Lab., Gainesville, FL (United States)

    1998-01-01

    Morphologically similar cryptic species are common in insects. In Anopheles mosquitoes morphologically described species are complexes of cryptic species. Cryptic species are of great practical importance for two reasons: first, one or more species of the complex might not be a pest and control efforts directed at the complex as a whole would therefore be partly wasted; and second, genetic (and perhaps biological) control strategies directed against one species of the complex would not affect other species of the complex. At least one SIT effort has failed because the released sterile insect were of a different species and therefore did not mate with the wild insects being targeted. We use a multidisciplinary approach for detection of cryptic species complexes, focusing first on identifying variability in wild populations using RFLPs of mitochondrial and ribosomal RNA genes (mtDNA and rDNA); followed by confirmation using a variety of other techniques. For rapid identification of wild individuals of field collections, we use a DNA dot blot assay. DNA probes can be isolated by differential screening, however we are currently focusing on the sequencing of the rDNA extragenic spacers. These regions are repeated several hundred times per genome in mosquitoes and evolve rapidly. Molecular drive tends to keen the individual genes homogeneous within a species. (author). 11 refs, 2 figs, 2 tabs.

  5. Chapter 16: Species Diversity

    African Journals Online (AJOL)

    zargaran

    2012-05-03

    May 3, 2012 ... rarefaction method was recorded in Pardanan, with 28 oak gall wasps species. Furthermore, the highest amount of Gini-Simpson and Shannon entropy index were recorded in Sardasht, while the highest evenness was recorded in Shalmash. Differences in the local distribution of oak species, especially.

  6. The Origin of Species

    NARCIS (Netherlands)

    Darwin, Charles

    2005-01-01

    In The Origin of Species Darwin outlined his theory of evolution, which proposed that species had been evolving and differentiating over time under the influence of natural selection. On its publication it became hugely influential, bringing about a seismic shift in the scientific view of humanitys

  7. Aquatic species and habitats

    Science.gov (United States)

    Danny C. Lee; James R. Sedell; Bruce E. Rieman; Russell F. Thurow; Jack E. Williams

    1998-01-01

    Continuing human activities threaten the highly prized aquatic resources of the interior Columbia basin. Precipitous declines in native species, particularly Pacific salmon, and a large influx of introduced species have radically altered the composition and distribution of native fishes. Fortunately, areas of relatively high aquatic integrity remain, much of it on...

  8. Support your local species

    DEFF Research Database (Denmark)

    Stärk, Johanna

    Nearly a quarter of all animal species within the European Union are threatened with extinction. Protecting many of these species will require the full spectrum of conservation actions from in-situ to ex-situ management. Holding an estimated 44% of EU Red Listed terrestrial vertebrates, zoos hereby...

  9. Extragastric Helicobacter species

    DEFF Research Database (Denmark)

    On, Stephen L.W.; Hynes, S.; Wadstrom, T.

    2002-01-01

    The genus Helicobacter has expanded at a rapid pace and no fewer than 31 species have been named since the proposal of the genus in 1989. Of these 31 species, 22 are principally associated with extragastric niches and there is increasing interest in the role of these taxa in diseases of humans...... and animals. Substantial evidence attests to certain species playing a role in the pathogenesis of enteric, hepatic and biliary disorders and some taxa demonstrate zoonotic potential. The importance of extragastric Helicobacters is likely to be an important topic for research in the near future. Here...

  10. The species in primatology.

    Science.gov (United States)

    Groves, Colin

    2014-01-01

    Biologists of the late eighteenth and early nineteenth centuries all bandied about the term "species," but very rarely actually said what they meant by it. Often, however, one can get inside their thinking by piecing together some of their remarks. One of the most nearly explicit-appropriately, for the man who wrote a book called The Origin of Species - was Charles Darwin: "Practically, when a naturalist can unite two forms together by others having intermediate characters, he treats the one as a variety of the other… He later translated this into evolutionary terms: "Hereafter, we shall be compelled to acknowledge that the only distinction between species and well-marked varieties is, that the latter are known, or believed, to be connected at the present day by intermediate gradations, whereas species were formerly thus connected"(1:484-5.) Copyright © 2014 Wiley Periodicals, Inc.

  11. Hierarchical species distribution models

    Science.gov (United States)

    Hefley, Trevor J.; Hooten, Mevin B.

    2016-01-01

    Determining the distribution pattern of a species is important to increase scientific knowledge, inform management decisions, and conserve biodiversity. To infer spatial and temporal patterns, species distribution models have been developed for use with many sampling designs and types of data. Recently, it has been shown that count, presence-absence, and presence-only data can be conceptualized as arising from a point process distribution. Therefore, it is important to understand properties of the point process distribution. We examine how the hierarchical species distribution modeling framework has been used to incorporate a wide array of regression and theory-based components while accounting for the data collection process and making use of auxiliary information. The hierarchical modeling framework allows us to demonstrate how several commonly used species distribution models can be derived from the point process distribution, highlight areas of potential overlap between different models, and suggest areas where further research is needed.

  12. Endangered Species: Pesticide Restrictions

    Science.gov (United States)

    Our goal is to protect threatened and endangered species and their habitats, without placing unnecessary burden on agriculture and pesticide users. Pesticide limitations are developed to ensure safe use of pesticides in order to meet this goal.

  13. Threatened & Endangered Species Occurrences

    Data.gov (United States)

    Kansas Data Access and Support Center — The database consists of a single statewide coverage of location records for 54 species contained in the Kansas Natural Heritage Inventory database of the Kansas...

  14. Sub specie aeternitatis

    Directory of Open Access Journals (Sweden)

    Laura Gioeni

    2012-10-01

    Full Text Available Per delineare il rapporto tra etica ed estetica nell'architettura e rispondere alla domanda principale «che cosa è o dovrebbe essere un buon architetto?», il saggio discute la tesi di Wittgenstein secondo cui «l'opera d'arte è l'oggetto visto sub specie aeternitatis e la vita buona è il mondo visto sub specie aeternitatis. Questa è la connessione tra arte ed etica».

  15. Genomic definition of species

    Energy Technology Data Exchange (ETDEWEB)

    Crkvenjakov, R.; Drmanac, R.

    1991-07-01

    The subject of this paper is the definition of species based on the assumption that genome is the fundamental level for the origin and maintenance of biological diversity. For this view to be logically consistent it is necessary to assume the existence and operation of the new law which we call genome law. For this reason the genome law is included in the explanation of species phenomenon presented here even if its precise formulation and elaboration are left for the future. The intellectual underpinnings of this definition can be traced to Goldschmidt. We wish to explore some philosophical aspects of the definition of species in terms of the genome. The point of proposing the definition on these grounds is that any real advance in evolutionary theory has to be correct in both its philosophy and its science.

  16. Bounding species distribution models

    Directory of Open Access Journals (Sweden)

    Thomas J. STOHLGREN, Catherine S. JARNEVICH, Wayne E. ESAIAS,Jeffrey T. MORISETTE

    2011-10-01

    Full Text Available Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for “clamping” model extrapolations. We relied on two commonly used modeling approaches: classification and regression tree (CART and maximum entropy (Maxent models, and we tested a simple alteration of the model extrapolations, bounding extrapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5: 642–647, 2011].

  17. Bounding Species Distribution Models

    Science.gov (United States)

    Stohlgren, Thomas J.; Jarnevich, Cahterine S.; Morisette, Jeffrey T.; Esaias, Wayne E.

    2011-01-01

    Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS) might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for "clamping" model extrapolations. We relied on two commonly used modeling approaches: classification and regression tree (CART) and maximum entropy (Maxent) models, and we tested a simple alteration of the model extrapolations, bounding extrapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5): 642-647, 2011].

  18. Aquatic Nuisance Species Locator

    Science.gov (United States)

    Data in this map has been collected by the United States Geological Survey's Nonindigenous Aquatic Species program located in Gainesville, Florida (http://nas.er.usgs.gov/default.aspx). This dataset may have some inaccuracies and is only current to June 15, 2012. The species identified in this dataset are not inclusive of all aquatic nuisance species, but rather a subset identified to be at risk for transport by recreational activities such as boating and angling. Additionally, the locations where organisims have been identified are also not inclusive and should be treated as a guide. Organisms are limited to the following: American bullfrog, Asian clam, Asian shore crab, Asian tunicate, Australian spotted jellyfish, Chinese mitten crab, New Zealand mudsnail, Colonial sea squirt, Alewife, Bighead carp, Black carp, Flathead catfish, Grass carp, Green crab, Lionfish, Northern snakehead, Quagga mussel, Round Goby, Ruffe, Rusty crayfish, Sea lamprey, Silver carp, Spiny water flea, Veined rapa whelk, Zebra mussel

  19. Man as a Species.

    Science.gov (United States)

    Solem, Alan; And Others

    Written in 1964, the document represents experimental material of the Anthropology Curriculum Study Project. The objectives of the project were to discuss the evolution of man as distinguished from the evolution of other species and as related to culture, and to emphasize human diversity. Three brief essays are presented. The first, "The…

  20. Coevolution of Symbiotic Species

    OpenAIRE

    Leok, Boon Tiong Melvin

    1996-01-01

    This paper will consider the coevolution of species which are symbiotic in their interaction. In particular, we shall analyse the interaction of squirrels and oak trees, and develop a mathematical framework for determining the coevolutionary equilibrium for consumption and production patterns.

  1. Colobanthus Quitensis (H.B.K. Bartl. (Caryophyllaceae en los Andes Colombianos

    Directory of Open Access Journals (Sweden)

    Aguirre C. Jaime

    1982-04-01

    Full Text Available Colobantbus quitensis y Deschampsia antarctica son las dos únicas fanerogamas nativas presentes hoy dia en el continente antártico (Green, 1970. La primera tiene una distribución amplia en regiones templadas y frías de América Latina, desde la Tierra del Fuego hasta México (Moore, 1972.  En noviembre de 1978 se realizó una exploración geobotánica corta al Páramo Alto del Almorzadero en la Cordillera Oriental, Departamento de Santander; en el piso pantanoso de un vallecito a 3.900 m (El Tutal se encontraron algunas maticas dispersas de Colobanthus quitensis (biótipo laxa cerca de una corriente lenta de agua. El hallazgo anterior de Colobanthus quitensis en la región del Nevado del Ruiz en la Cordillera Central motivó la elaboración del presente trabajo, con el fin de dar a conocer los caracteres morfológicos, palinológicos y sociológicos de esta interesante especie.

  2. Colonization and diversification in the African “sky islands” by Eurasian Lychnis L. (Caryophyllaceae)

    Czech Academy of Sciences Publication Activity Database

    Popp, M.; Gizaw, A.; Nemomissa, S.; Suda, Jan; Brochmann, C.

    2008-01-01

    Roč. 35, č. 6 (2008), s. 1016-1029 ISSN 0305-0270 Institutional research plan: CEZ:AV0Z60050516 Keywords : evolution * cytometry * phylogeography Subject RIV: EF - Botanics Impact factor: 4.566, year: 2008

  3. Divergent biology of facultative heavy metal plants.

    Science.gov (United States)

    Bothe, Hermann; Słomka, Aneta

    2017-12-01

    Among heavy metal plants (the metallophytes), facultative species can live both in soils contaminated by an excess of heavy metals and in non-affected sites. In contrast, obligate metallophytes are restricted to polluted areas. Metallophytes offer a fascinating biology, due to the fact that species have developed different strategies to cope with the adverse conditions of heavy metal soils. The literature distinguishes between hyperaccumulating, accumulating, tolerant and excluding metallophytes, but the borderline between these categories is blurred. Due to the fact that heavy metal soils are dry, nutrient limited and are not uniform but have a patchy distribution in many instances, drought-tolerant or low nutrient demanding species are often regarded as metallophytes in the literature. In only a few cases, the concentrations of heavy metals in soils are so toxic that only a few specifically adapted plants, the genuine metallophytes, can cope with these adverse soil conditions. Current molecular biological studies focus on the genetically amenable and hyperaccumulating Arabidopsis halleri and Noccaea (Thlaspi) caerulescens of the Brassicaceae. Armeria maritima ssp. halleri utilizes glands for the excretion of heavy metals and is, therefore, a heavy metal excluder. The two endemic zinc violets of Western Europe, Viola lutea ssp. calaminaria of the Aachen-Liège area and Viola lutea ssp. westfalica of the Pb-Cu-ditch of Blankenrode, Eastern Westphalia, as well as Viola tricolor ecotypes of Eastern Europe, keep their cells free of excess heavy metals by arbuscular mycorrhizal fungi which bind heavy metals. The Caryophyllaceae, Silene vulgaris f. humilis and Minuartia verna, apparently discard leaves when overloaded with heavy metals. All Central European metallophytes have close relatives that grow in areas outside of heavy metal soils, mainly in the Alps, and have, therefore, been considered as relicts of the glacial epoch in the past. However, the current

  4. Positive feedback in species communities

    NARCIS (Netherlands)

    Gerla, D.J.

    2012-01-01

    Sometimes the eventual population densities in a species community depend on the initial densities or the arrival times of species. If arrival times determine species composition, a priority effect has occurred. Priority effects may occur if the species community exhibits alternative stable states

  5. The functional biogeography of species

    DEFF Research Database (Denmark)

    Carstensen, Daniel W.; Dalsgaard, Bo; Svenning, Jens-Christian

    2013-01-01

    Biogeographical systems can be analyzed as networks of species and geographical units. Within such a biogeographical network, individual species may differ fundamentally in their linkage pattern, and therefore hold different topological roles. To advance our understanding of the relationship betw...... to distributions at the local community level. We finally discuss how our biogeographical species roles may correspond to the stages of the taxon cycle and other prominent theories of species assembly.......Biogeographical systems can be analyzed as networks of species and geographical units. Within such a biogeographical network, individual species may differ fundamentally in their linkage pattern, and therefore hold different topological roles. To advance our understanding of the relationship...... between species traits and large-scale species distribution patterns in archipelagos, we use a network approach to classify birds as one of four biogeographical species roles: peripherals, connectors, module hubs, and network hubs. These roles are based upon the position of species within the modular...

  6. Autecology of broadleaved species

    OpenAIRE

    Gonin, Pierre; Larrieu, Laurent; Coello, Jaime; Marty, Pauline; Lestrade , Marine; Becquey, Jacques; Claessens, Hugues

    2013-01-01

    Anyone involved in timber production needs some knowledge of autecology. With the renewed interest in hardwoods in the last 20 years, they are increasingly being introduced by planting or encouraged in natural stands. The results in terms of growth have not always met foresters’ expectations, due to technical problems and especially because the species are not always suited to the different sites. While the principle of establishing hardwoods is not in question, it is important to be aware of...

  7. Prior indigenous technological species

    Science.gov (United States)

    Wright, Jason T.

    2018-01-01

    One of the primary open questions of astrobiology is whether there is extant or extinct life elsewhere the solar system. Implicit in much of this work is that we are looking for microbial or, at best, unintelligent life, even though technological artefacts might be much easier to find. Search for Extraterrestrial Intelligence (SETI) work on searches for alien artefacts in the solar system typically presumes that such artefacts would be of extrasolar origin, even though life is known to have existed in the solar system, on Earth, for eons. But if a prior technological, perhaps spacefaring, species ever arose in the solar system, it might have produced artefacts or other technosignatures that have survived to present day, meaning solar system artefact SETI provides a potential path to resolving astrobiology's question. Here, I discuss the origins and possible locations for technosignatures of such a prior indigenous technological species, which might have arisen on ancient Earth or another body, such as a pre-greenhouse Venus or a wet Mars. In the case of Venus, the arrival of its global greenhouse and potential resurfacing might have erased all evidence of its existence on the Venusian surface. In the case of Earth, erosion and, ultimately, plate tectonics may have erased most such evidence if the species lived Gyr ago. Remaining indigenous technosignatures might be expected to be extremely old, limiting the places they might still be found to beneath the surfaces of Mars and the Moon, or in the outer solar system.

  8. Estimating Effects of Species Interactions on Populations of Endangered Species.

    Science.gov (United States)

    Roth, Tobias; Bühler, Christoph; Amrhein, Valentin

    2016-04-01

    Global change causes community composition to change considerably through time, with ever-new combinations of interacting species. To study the consequences of newly established species interactions, one available source of data could be observational surveys from biodiversity monitoring. However, approaches using observational data would need to account for niche differences between species and for imperfect detection of individuals. To estimate population sizes of interacting species, we extended N-mixture models that were developed to estimate true population sizes in single species. Simulations revealed that our model is able to disentangle direct effects of dominant on subordinate species from indirect effects of dominant species on detection probability of subordinate species. For illustration, we applied our model to data from a Swiss amphibian monitoring program and showed that sizes of expanding water frog populations were negatively related to population sizes of endangered yellow-bellied toads and common midwife toads and partly of natterjack toads. Unlike other studies that analyzed presence and absence of species, our model suggests that the spread of water frogs in Central Europe is one of the reasons for the decline of endangered toad species. Thus, studying population impacts of dominant species on population sizes of endangered species using data from biodiversity monitoring programs should help to inform conservation policy and to decide whether competing species should be subject to population management.

  9. CHROMOSOMES OF WOODY SPECIES

    Directory of Open Access Journals (Sweden)

    Julio R Daviña

    2000-01-01

    Full Text Available Chromosome numbers of nine subtropical woody species collected in Argentina and Paraguay are reported. The counts tor Coutarea hexandra (2n=52, Inga vera subsp. affinis 2n=26 (Fabaceae and Chorisia speciosa 2n=86 (Bombacaceae are reported for the first time. The chromosome number given for Inga semialata 2n=52 is a new cytotype different from the previously reported. Somatic chromosome numbers of the other taxa studied are: Sesbania punicea 2n=12, S. virgata 2n=12 and Pilocarpus pennatifolius 2n=44 from Argentina

  10. Save Our Species: Protecting Endangered Species from Pesticides.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC.

    This full-size poster profiles 11 wildlife species that are endangered. Color illustrations of animals and plants are accompanied by narrative describing their habitats and reasons for endangerment. The reverse side of the poster contains information on the Endangered Species Act, why protecting endangered and threatened species is important, how…

  11. New species of Malaysian ferns

    NARCIS (Netherlands)

    Holttum, R.E.

    1962-01-01

    The present paper includes descriptions of several new species of ferns found among recent collections from various parts of Malaysia; also two new combinations of names of species which are of interest on account of their taxonomic history.

  12. Endangered Species Act Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Critical habitat (CH) is designated for the survival and recovery of species listed as threatened or endangered under the Endangered Species Act (ESA). Critical...

  13. New Malesian species of Viscaceae

    NARCIS (Netherlands)

    Barlow, Bryan A.

    1996-01-01

    Three new Malesian species of Viscaceae are described. Ginalloa flagellaris Barlow is distinguished as a species from New Guinea and New Britain, previously included within G. arnottiana Korthals. Viscum exile Barlow is recognized as a new species endemic to Celebes, related to V. ovalifolium.

  14. Lichen species preference by reindeer

    Energy Technology Data Exchange (ETDEWEB)

    Holleman, D F; Luick, J R

    1977-08-01

    The preference by reindeer for five species of lichens commonly found on Central Alaska rangelands was tested under controlled laboratory conditions. Results indicate that reindeer are strongly selective species in their lichen grazing habits. The five tested species ranged as follows in order of decreasing acceptibility: Caldonia alpestris, C. rangiferina, Stereocaulon paschale, Cetraria richardsonii, and Peltigera aphthosa.

  15. 75 FR 78974 - Endangered Species

    Science.gov (United States)

    2010-12-17

    ...-XA086 Endangered Species AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... the Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.) and the regulations governing the taking, importing, and exporting of endangered and threatened species (50 CFR 222-226). Permit...

  16. California Endangered Species Resource Guide.

    Science.gov (United States)

    California State Dept. of Education, Los Angeles.

    This document was developed in response to California Senate Bill No. 885, "The Endangered Species Education Project," that called for a statewide program in which schools adopt a local endangered species, research past and current efforts to preserve the species' habitat, develop and implement an action plan to educate the community…

  17. 76 FR 2348 - Endangered Species

    Science.gov (United States)

    2011-01-13

    .... 15596] Endangered Species AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... requested permit has been issued under the authority of the Endangered Species Act of 1973, as amended (ESA... endangered and threatened species (50 CFR parts 222-226). The North Carolina Aquarium at Fort Fisher has been...

  18. Electrosmog and species conservation

    Energy Technology Data Exchange (ETDEWEB)

    Balmori, Alfonso, E-mail: abalmorimartinez@gmail.com

    2014-10-15

    Despite the widespread use of wireless telephone networks around the world, authorities and researchers have paid little attention to the potential harmful effects of mobile phone radiation on wildlife. This paper briefly reviews the available scientific information on this topic and recommends further studies and specific lines of research to confirm or refute the experimental results to date. Controls must be introduced and technology rendered safe for the environment, particularly, threatened species. - Highlights: • Studies have shown effects in both animals and plants. • Two thirds of the studies reported ecological effects. • There is little research in this area and further research is needed. • The technology must be safe. • Controls should be introduced to mitigate the possible effects.

  19. Management of invasive species

    DEFF Research Database (Denmark)

    Schou, Jesper Sølver; Jensen, Frank

    impact of the establishment of this invasive species is a substantial increase in the number of allergy cases, which we use as a measure of the physical damage. As valuation methods, we use both the cost-of-illness method and the benefit transfer method to quantify the total gross benefits of the two...... policy actions. Based on the idea of an invasion function, we identify the total and average net benefit under both prevention and mitigation. For both policy actions, the total and average net benefits are significantly positive irrespective of the valuation method used; therefore, both prevention...... and mitigation are beneficial policy actions. However, the total and average net benefits under mitigation are larger than the benefits under prevention, implying that the former policy action is more beneficial. Despite this result, we conclude that prevention, not mitigation, shall be used because...

  20. Prices and species diversity

    DEFF Research Database (Denmark)

    Sauer, Johannes

    of biodiversity and the appropriate incorporation in stochastic fron-tier models to achieve more realistic measures of production efficiency. We use the empirical example of tobacco production drawing from as well as affecting species diversity in the surrounding forests. We apply a shadow profit distance......In recent decades a significant amount of literature has been produced concerned with establishing a link between production efficiency and environmental efficiency with respect to quantitative modelling. This has been mainly addressed by focusing on the incorporation of undesirable outputs...... or the incorporation of environmentally det-rimental inputs. However, while the debate with respect to linear programming based DEA modelling is already at an advanced stage the corresponding one with respect to stochastic frontier modelling still needs considerable efforts. This contribution fo-cuses on the case...

  1. Reactive Oxygen Species

    DEFF Research Database (Denmark)

    Franchina, Davide G.; Dostert, Catherine; Brenner, Dirk

    2018-01-01

    T cells are a central component of defenses against pathogens and tumors. Their effector functions are sustained by specific metabolic changes that occur upon activation, and these have been the focus of renewed interest. Energy production inevitably generates unwanted products, namely reactive...... and transcription factors, influencing the outcome of the T cell response. We discuss here how ROS can directly fine-tune metabolism and effector functions of T cells....... oxygen species (ROS), which have long been known to trigger cell death. However, there is now evidence that ROS also act as intracellular signaling molecules both in steady-state and upon antigen recognition. The levels and localization of ROS contribute to the redox modeling of effector proteins...

  2. Introduced species as evolutionary traps

    Science.gov (United States)

    Schlaepfer, Martin A.; Sherman, P.W.; Blossey, B.; Runge, M.C.

    2005-01-01

    Invasive species can alter environments in such a way that normal behavioural decision-making rules of native species are no longer adaptive. The evolutionary trap concept provides a useful framework for predicting and managing the impact of harmful invasive species. We discuss how native species can respond to changes in their selective regime via evolution or learning. We also propose novel management strategies to promote the long-term co-existence of native and introduced species in cases where the eradication of the latter is either economically or biologically unrealistic.

  3. Insular species swarm goes underground

    DEFF Research Database (Denmark)

    P. S. Reboleira, Ana Sofia; Enghoff, Henrik

    2014-01-01

    Two new species of the genus Cylindroiulus Verhoeff, 1894, C. julesvernei and C. oromii, are described from the subterranean ecosystem of Madeira Island, Portugal. Species are illustrated with photographs and diagrammatic drawings. The new species belong to the Cylindroiulus madeirae......-group, an insular species swarm distributed in the archipelagos of Madeira and the Canary Islands. We discuss the differences between the new species and their relatives and present information on the subterranean environment of Madeira. An updated overview of the subterranean biodiversity of millipedes...

  4. Ring species as demonstrations of the continuum of species formation

    DEFF Research Database (Denmark)

    Pereira, Ricardo José Do Nascimento; Wake, David B.

    2015-01-01

    In the mid-20th century, Ernst Mayr (1942) and Theodosius Dobzhansky (1958) championed the significance of 'circular overlaps' or 'ring species' as the perfect demonstration of the gradual nature of species formation. As an ancestral species expands its range, wrapping around a geographic barrier......? What conditions favour their formation? Modelling studies have attempted to address these knowledge gaps by estimating the biological parameters that result in stable ring species (Martins et al. 2013), and determining the necessary topographic parameters of the barriers encircled (Monahan et al. 2012......). However, any generalization is undermined by a major limitation: only a handful of ring species are known to exist in nature. In addition, many of them have been broken into multiple species presumed to be evolving independently, usually obscuring the evolutionary dynamics that generate diversity. A paper...

  5. Species of Wadicosa (Araneae, Lycosidae): a new species from Madagascar.

    Science.gov (United States)

    Kronestedt, Torbjörn

    2017-05-10

    Since establishing the wolf spider genus Wadicosa Zyuzin, 1985 (Zyuzin 1985), eleven species have been accepted in it, either by transfer from Lycosa Latreille, 1804 or Pardosa C.L. Koch, 1847 or by original designation (WSC 2017). However, according to Kronestedt (1987), additional species wait to be formally transferred to Wadicosa. The genus is restricted to the Old World, with one species, Wadicosa jocquei Kronestedt, 2015, recently described from Madagascar and surrounding islands.

  6. Native species that can replace exotic species in landscaping

    Directory of Open Access Journals (Sweden)

    Elisabeth Regina Tempel Stumpf

    2015-08-01

    Full Text Available Beyond aesthetics, the contemporary landscaping intends to provide other benefits for humans and environment, especially related to the environmental quality of urban spaces and conservation of the species. A trend in this direction is the reduction in the use of exotic plants in their designs, since, over time, they can become agents of replacement of native flora, as it has occurred in Rio Grande do Sul with many species introduced by settlers. However, the use of exotic species is unjustifiable, because the flora diversity of the Bioma Pampa offers many native species with appropriate features to the ornamental use. The commercial cultivation and the implantation of native species in landscaped areas constitute innovations for plant nurseries and landscapers and can provide a positive reduction in extractivism, contributing to dissemination, exploitation and preservation of native flora, and also decrease the impact of chemical products on environment. So, this work intends to identify native species of Bioma Pampa with features and uses similar to the most used exotic species at Brazilian landscaping. The species were selected from consulting books about native plants of Bioma Pampa and plants used at Brazilian landscaping, considering the similarity on habit and architecture, as well as characteristics of leafs, flowers and/or fruits and environmental conditions of occurrence and cultivation. There were identified 34 native species able to properly replace exotic species commonly used. The results show that many native species of Bioma Pampa have interesting ornamental features to landscape gardening, allowing them to replace exotic species that are traditionally cultivated.

  7. Population genetics and cryptic species

    International Nuclear Information System (INIS)

    McPheron, Bruce A.

    2000-01-01

    Does the definition of a species matter for pest management purposes? Taxonomists provide us with tools - usually morphological characters - to identify a group of organisms that we call a species. The implication of this identification is that all of the individuals that fit the provided description are members of the species in question. The taxonomists have considered the range of variation among individuals in defining the species, but this variation is often forgotten when we take the concept of species to the level of management. Just as there is morphological variation among individuals, there is also variation in practically any character we might imagine, which has implications for the short and long term success of our management tactics. The rich literature on insecticide resistance should be a constant reminder of the fact that the pressure on pest survival and reproduction applied by our management approaches frequently leads to evolutionary changes within the pest species. The degree of variation within a particular species is a defining characteristic of that species. This level of variability may have very important implications for successful management, so it is very important to measure variation and, whenever possible, the genetic basis of that variation, in a target species. Population genetic approaches can provide evidence of genetic structure (or lack thereof) among populations of a species. These types of data can be used to discuss the movement of pest populations on a local or global scale. In other cases, we may have a complex of species that share some, but not all, characteristics. Species complexes that share morphological characters (i.e., cannot be easily distinguished) but not biological characters are referred to as sibling or cryptic species

  8. BUMBLEBEE VISITATION AND SEEDSET IN MELAMPYRUM-PRATENSE AND VISCARIA-VULGARIS - HETEROSPECIFIC POLLEN AND POLLEN LIMITATION

    NARCIS (Netherlands)

    KWAK, MM; JENNERSTEN, O

    1991-01-01

    Fruiting and seed set in two bumblebee-pollinated herbs, Melampyrum pratense L. (annual, Scrophulariaceae) and Viscaria vulgaris Bernh. (perennial, Caryophyllaceae) were studied on a dry meadow in south-western Sweden in June 1986 and 1988. Both species produced seeds by self-fertilization. In

  9. Confronting species distribution model predictions with species functional traits.

    Science.gov (United States)

    Wittmann, Marion E; Barnes, Matthew A; Jerde, Christopher L; Jones, Lisa A; Lodge, David M

    2016-02-01

    Species distribution models are valuable tools in studies of biogeography, ecology, and climate change and have been used to inform conservation and ecosystem management. However, species distribution models typically incorporate only climatic variables and species presence data. Model development or validation rarely considers functional components of species traits or other types of biological data. We implemented a species distribution model (Maxent) to predict global climate habitat suitability for Grass Carp (Ctenopharyngodon idella). We then tested the relationship between the degree of climate habitat suitability predicted by Maxent and the individual growth rates of both wild (N = 17) and stocked (N = 51) Grass Carp populations using correlation analysis. The Grass Carp Maxent model accurately reflected the global occurrence data (AUC = 0.904). Observations of Grass Carp growth rate covered six continents and ranged from 0.19 to 20.1 g day(-1). Species distribution model predictions were correlated (r = 0.5, 95% CI (0.03, 0.79)) with observed growth rates for wild Grass Carp populations but were not correlated (r = -0.26, 95% CI (-0.5, 0.012)) with stocked populations. Further, a review of the literature indicates that the few studies for other species that have previously assessed the relationship between the degree of predicted climate habitat suitability and species functional traits have also discovered significant relationships. Thus, species distribution models may provide inferences beyond just where a species may occur, providing a useful tool to understand the linkage between species distributions and underlying biological mechanisms.

  10. Balance of bacterial species in the gut

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Balance of bacterial species in the gut. Protective. Lactobacillus species. Bifidobacterium species. Selected E. coli. Saccharomyces boulardii. Clostridium butyricum.

  11. Quantifying the invasiveness of species

    Directory of Open Access Journals (Sweden)

    Robert Colautti

    2014-04-01

    Full Text Available The success of invasive species has been explained by two contrasting but non-exclusive views: (i intrinsic factors make some species inherently good invaders; (ii species become invasive as a result of extrinsic ecological and genetic influences such as release from natural enemies, hybridization or other novel ecological and evolutionary interactions. These viewpoints are rarely distinguished but hinge on distinct mechanisms leading to different management scenarios. To improve tests of these hypotheses of invasion success we introduce a simple mathematical framework to quantify the invasiveness of species along two axes: (i interspecific differences in performance among native and introduced species within a region, and (ii intraspecific differences between populations of a species in its native and introduced ranges. Applying these equations to a sample dataset of occurrences of 1,416 plant species across Europe, Argentina, and South Africa, we found that many species are common in their native range but become rare following introduction; only a few introduced species become more common. Biogeographical factors limiting spread (e.g. biotic resistance, time of invasion therefore appear more common than those promoting invasion (e.g. enemy release. Invasiveness, as measured by occurrence data, is better explained by inter-specific variation in invasion potential than biogeographical changes in performance. We discuss how applying these comparisons to more detailed performance data would improve hypothesis testing in invasion biology and potentially lead to more efficient management strategies.

  12. Uncommon Species and Other Features

    Data.gov (United States)

    Vermont Center for Geographic Information — The Vermont Fish and Wildlife Department's Natural Heritage Inventory (NHI) maintains a database of uncommon, rare, threatened and endangered species and natural...

  13. Incorporating Context Dependency of Species Interactions in Species Distribution Models.

    Science.gov (United States)

    Lany, Nina K; Zarnetske, Phoebe L; Gouhier, Tarik C; Menge, Bruce A

    2017-07-01

    Species distribution models typically use correlative approaches that characterize the species-environment relationship using occurrence or abundance data for a single species. However, species distributions are determined by both abiotic conditions and biotic interactions with other species in the community. Therefore, climate change is expected to impact species through direct effects on their physiology and indirect effects propagated through their resources, predators, competitors, or mutualists. Furthermore, the sign and strength of species interactions can change according to abiotic conditions, resulting in context-dependent species interactions that may change across space or with climate change. Here, we incorporated the context dependency of species interactions into a dynamic species distribution model. We developed a multi-species model that uses a time-series of observational survey data to evaluate how abiotic conditions and species interactions affect the dynamics of three rocky intertidal species. The model further distinguishes between the direct effects of abiotic conditions on abundance and the indirect effects propagated through interactions with other species. We apply the model to keystone predation by the sea star Pisaster ochraceus on the mussel Mytilus californianus and the barnacle Balanus glandula in the rocky intertidal zone of the Pacific coast, USA. Our method indicated that biotic interactions between P. ochraceus and B. glandula affected B. glandula dynamics across >1000 km of coastline. Consistent with patterns from keystone predation, the growth rate of B. glandula varied according to the abundance of P. ochraceus in the previous year. The data and the model did not indicate that the strength of keystone predation by P. ochraceus varied with a mean annual upwelling index. Balanus glandula cover increased following years with high phytoplankton abundance measured as mean annual chlorophyll-a. M. californianus exhibited the same

  14. Previously unknown species of Aspergillus.

    Science.gov (United States)

    Gautier, M; Normand, A-C; Ranque, S

    2016-08-01

    The use of multi-locus DNA sequence analysis has led to the description of previously unknown 'cryptic' Aspergillus species, whereas classical morphology-based identification of Aspergillus remains limited to the section or species-complex level. The current literature highlights two main features concerning these 'cryptic' Aspergillus species. First, the prevalence of such species in clinical samples is relatively high compared with emergent filamentous fungal taxa such as Mucorales, Scedosporium or Fusarium. Second, it is clearly important to identify these species in the clinical laboratory because of the high frequency of antifungal drug-resistant isolates of such Aspergillus species. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) has recently been shown to enable the identification of filamentous fungi with an accuracy similar to that of DNA sequence-based methods. As MALDI-TOF MS is well suited to the routine clinical laboratory workflow, it facilitates the identification of these 'cryptic' Aspergillus species at the routine mycology bench. The rapid establishment of enhanced filamentous fungi identification facilities will lead to a better understanding of the epidemiology and clinical importance of these emerging Aspergillus species. Based on routine MALDI-TOF MS-based identification results, we provide original insights into the key interpretation issues of a positive Aspergillus culture from a clinical sample. Which ubiquitous species that are frequently isolated from air samples are rarely involved in human invasive disease? Can both the species and the type of biological sample indicate Aspergillus carriage, colonization or infection in a patient? Highly accurate routine filamentous fungi identification is central to enhance the understanding of these previously unknown Aspergillus species, with a vital impact on further improved patient care. Copyright © 2016 European Society of Clinical Microbiology and

  15. Fuzzy species among recombinogenic bacteria

    Directory of Open Access Journals (Sweden)

    Fraser Christophe

    2005-03-01

    Full Text Available Abstract Background It is a matter of ongoing debate whether a universal species concept is possible for bacteria. Indeed, it is not clear whether closely related isolates of bacteria typically form discrete genotypic clusters that can be assigned as species. The most challenging test of whether species can be clearly delineated is provided by analysis of large populations of closely-related, highly recombinogenic, bacteria that colonise the same body site. We have used concatenated sequences of seven house-keeping loci from 770 strains of 11 named Neisseria species, and phylogenetic trees, to investigate whether genotypic clusters can be resolved among these recombinogenic bacteria and, if so, the extent to which they correspond to named species. Results Alleles at individual loci were widely distributed among the named species but this distorting effect of recombination was largely buffered by using concatenated sequences, which resolved clusters corresponding to the three species most numerous in the sample, N. meningitidis, N. lactamica and N. gonorrhoeae. A few isolates arose from the branch that separated N. meningitidis from N. lactamica leading us to describe these species as 'fuzzy'. Conclusion A multilocus approach using large samples of closely related isolates delineates species even in the highly recombinogenic human Neisseria where individual loci are inadequate for the task. This approach should be applied by taxonomists to large samples of other groups of closely-related bacteria, and especially to those where species delineation has historically been difficult, to determine whether genotypic clusters can be delineated, and to guide the definition of species.

  16. 76 FR 74778 - Endangered Species

    Science.gov (United States)

    2011-12-01

    .... 16439] Endangered Species AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... has been issued under the authority of the Endangered Species Act of 1973, as amended (ESA; 16 U.S.C. 1531 et seq.) and the regulations governing the taking, importing, and exporting of endangered and...

  17. [Yeast species in vulvovaginitis candidosa].

    Science.gov (United States)

    Nemes-Nikodém, Éva; Tamási, Béla; Mihalik, Noémi; Ostorházi, Eszter

    2015-01-04

    Vulvovaginal candidiasis is the most common mycosis, however, the available information about antifungal susceptibilities of these yeasts is limited. To compare the gold standard fungal culture with a new molecular identification method and report the incidence of yeast species in vulvovaginitis candidosa. The authors studied 370 yeasts isolated from vulvovaginal candidiasis and identified them by phenotypic and molecular methods. The most common species was Candida albicans (85%), followed by Candida glabrata, and other Candida species. At present there are no recommendations for the evaluation of antifungal susceptibility of pathogenic fungal species occurring in vulvovaginal candidiasis and the natural antifungal resistance of the different species is known only. Matrix Assisted Laser Desorption Ionization Time of Flight identification can be used to differentiate the fluconazole resistant Candida dubliniensis and the sensitive Candida albicans strains.

  18. Enolonium Species-Umpoled Enolates

    DEFF Research Database (Denmark)

    Arava, Shlomy; Kumar, Jayprakash N.; Maksymenko, Shimon

    2017-01-01

    Enolonium species/iodo(III) enolates of carbonyl compounds have been suggested to be intermediates in a wide variety of hypervalent iodine induced chemical transformations of ketones, including α-C-O, α-C-N, α-C-C, and alpha-carbon- halide bond formation, but they have never been characterized. We...... report that these elusive umpoled enolates may be made as discrete species that are stable for several minutes at-78 degrees C, and report the first spectroscopic identification of such species. It is shown that enolonium species are direct intermediates in C-O, C-N, C-Cl, and C-C bond forming reactions....... Our results open up chemical space for designing a variety of new transformations. We showcase the ability of enolonium species to react with prenyl, crotyl, cinnamyl, and allyl silanes with absolute regioselectivity in up to 92% yield....

  19. Species concepts, species delimitation and the inherent limitations

    Indian Academy of Sciences (India)

    Frank Zachos

    synchrony and to sexually reproducing organisms would not be a problem anymore ... approach to species delimitation that combines genetic data with .... The datasets or algorithms could then be modified so that the groups yielded conform.

  20. Genome Sequences of Oryza Species

    KAUST Repository

    Kumagai, Masahiko; Tanaka, Tsuyoshi; Ohyanagi, Hajime; Hsing, Yue-Ie C.; Itoh, Takeshi

    2018-01-01

    This chapter summarizes recent data obtained from genome sequencing, annotation projects, and studies on the genome diversity of Oryza sativa and related Oryza species. O. sativa, commonly known as Asian rice, is the first monocot species whose complete genome sequence was deciphered based on physical mapping by an international collaborative effort. This genome, along with its accurate and comprehensive annotation, has become an indispensable foundation for crop genomics and breeding. With the development of innovative sequencing technologies, genomic studies of O. sativa have dramatically increased; in particular, a large number of cultivars and wild accessions have been sequenced and compared with the reference rice genome. Since de novo genome sequencing has become cost-effective, the genome of African cultivated rice, O. glaberrima, has also been determined. Comparative genomic studies have highlighted the independent domestication processes of different rice species, but it also turned out that Asian and African rice share a common gene set that has experienced similar artificial selection. An international project aimed at constructing reference genomes and examining the genome diversity of wild Oryza species is currently underway, and the genomes of some species are publicly available. This project provides a platform for investigations such as the evolution, development, polyploidization, and improvement of crops. Studies on the genomic diversity of Oryza species, including wild species, should provide new insights to solve the problem of growing food demands in the face of rapid climatic changes.

  1. Genome Sequences of Oryza Species

    KAUST Repository

    Kumagai, Masahiko

    2018-02-14

    This chapter summarizes recent data obtained from genome sequencing, annotation projects, and studies on the genome diversity of Oryza sativa and related Oryza species. O. sativa, commonly known as Asian rice, is the first monocot species whose complete genome sequence was deciphered based on physical mapping by an international collaborative effort. This genome, along with its accurate and comprehensive annotation, has become an indispensable foundation for crop genomics and breeding. With the development of innovative sequencing technologies, genomic studies of O. sativa have dramatically increased; in particular, a large number of cultivars and wild accessions have been sequenced and compared with the reference rice genome. Since de novo genome sequencing has become cost-effective, the genome of African cultivated rice, O. glaberrima, has also been determined. Comparative genomic studies have highlighted the independent domestication processes of different rice species, but it also turned out that Asian and African rice share a common gene set that has experienced similar artificial selection. An international project aimed at constructing reference genomes and examining the genome diversity of wild Oryza species is currently underway, and the genomes of some species are publicly available. This project provides a platform for investigations such as the evolution, development, polyploidization, and improvement of crops. Studies on the genomic diversity of Oryza species, including wild species, should provide new insights to solve the problem of growing food demands in the face of rapid climatic changes.

  2. Species interactions and plant polyploidy.

    Science.gov (United States)

    Segraves, Kari A; Anneberg, Thomas J

    2016-07-01

    Polyploidy is a common mode of speciation that can have far-reaching consequences for plant ecology and evolution. Because polyploidy can induce an array of phenotypic changes, there can be cascading effects on interactions with other species. These interactions, in turn, can have reciprocal effects on polyploid plants, potentially impacting their establishment and persistence. Although there is a wealth of information on the genetic and phenotypic effects of polyploidy, the study of species interactions in polyploid plants remains a comparatively young field. Here we reviewed the available evidence for how polyploidy may impact many types of species interactions that range from mutualism to antagonism. Specifically, we focused on three main questions: (1) Does polyploidy directly cause the formation of novel interactions not experienced by diploids, or does it create an opportunity for natural selection to then form novel interactions? (2) Does polyploidy cause consistent, predictable changes in species interactions vs. the evolution of idiosyncratic differences? (3) Does polyploidy lead to greater evolvability in species interactions? From the scarce evidence available, we found that novel interactions are rare but that polyploidy can induce changes in pollinator, herbivore, and pathogen interactions. Although further tests are needed, it is likely that selection following whole-genome duplication is important in all types of species interaction and that there are circumstances in which polyploidy can enhance the evolvability of interactions with other species. © 2016 Botanical Society of America.

  3. Scale dependence in species turnover reflects variance in species occupancy.

    Science.gov (United States)

    McGlinn, Daniel J; Hurlbert, Allen H

    2012-02-01

    Patterns of species turnover may reflect the processes driving community dynamics across scales. While the majority of studies on species turnover have examined pairwise comparison metrics (e.g., the average Jaccard dissimilarity), it has been proposed that the species-area relationship (SAR) also offers insight into patterns of species turnover because these two patterns may be analytically linked. However, these previous links only apply in a special case where turnover is scale invariant, and we demonstrate across three different plant communities that over 90% of the pairwise turnover values are larger than expected based on scale-invariant predictions from the SAR. Furthermore, the degree of scale dependence in turnover was negatively related to the degree of variance in the occupancy frequency distribution (OFD). These findings suggest that species turnover diverges from scale invariance, and as such pairwise turnover and the slope of the SAR are not redundant. Furthermore, models developed to explain the OFD should be linked with those developed to explain species turnover to achieve a more unified understanding of community structure.

  4. Species-area relationships are controlled by species traits.

    Science.gov (United States)

    Franzén, Markus; Schweiger, Oliver; Betzholtz, Per-Eric

    2012-01-01

    The species-area relationship (SAR) is one of the most thoroughly investigated empirical relationships in ecology. Two theories have been proposed to explain SARs: classical island biogeography theory and niche theory. Classical island biogeography theory considers the processes of persistence, extinction, and colonization, whereas niche theory focuses on species requirements, such as habitat and resource use. Recent studies have called for the unification of these two theories to better explain the underlying mechanisms that generates SARs. In this context, species traits that can be related to each theory seem promising. Here we analyzed the SARs of butterfly and moth assemblages on islands differing in size and isolation. We tested whether species traits modify the SAR and the response to isolation. In addition to the expected overall effects on the area, traits related to each of the two theories increased the model fit, from 69% up to 90%. Steeper slopes have been shown to have a particularly higher sensitivity to area, which was indicated by species with restricted range (slope = 0.82), narrow dietary niche (slope= 0.59), low abundance (slope= 0.52), and low reproductive potential (slope = 0.51). We concluded that considering species traits by analyzing SARs yields considerable potential for unifying island biogeography theory and niche theory, and that the systematic and predictable effects observed when considering traits can help to guide conservation and management actions.

  5. Multiple mechanisms enable invasive species to suppress native species.

    Science.gov (United States)

    Bennett, Alison E; Thomsen, Meredith; Strauss, Sharon Y

    2011-07-01

    Invasive plants represent a significant threat to ecosystem biodiversity. To decrease the impacts of invasive species, a major scientific undertaking of the last few decades has been aimed at understanding the mechanisms that drive invasive plant success. Most studies and theories have focused on a single mechanism for predicting the success of invasive plants and therefore cannot provide insight as to the relative importance of multiple interactions in predicting invasive species' success. We examine four mechanisms that potentially contribute to the success of invasive velvetgrass Holcus lanatus: direct competition, indirect competition mediated by mammalian herbivores, interference competition via allelopathy, and indirect competition mediated by changes in the soil community. Using a combination of field and greenhouse approaches, we focus on the effects of H. lanatus on a common species in California coastal prairies, Erigeron glaucus, where the invasion is most intense. We found that H. lanatus had the strongest effects on E. glaucus via direct competition, but it also influenced the soil community in ways that feed back to negatively influence E. glaucus and other native species after H. lanatus removal. This approach provided evidence for multiple mechanisms contributing to negative effects of invasive species, and it identified when particular strategies were most likely to be important. These mechanisms can be applied to eradication of H. lanatus and conservation of California coastal prairie systems, and they illustrate the utility of an integrated set of experiments for determining the potential mechanisms of invasive species' success.

  6. Evolution of mutualism between species

    Energy Technology Data Exchange (ETDEWEB)

    Post, W.M.; Travis, C.C.; DeAngelis, D.L.

    1980-01-01

    Recent theoretical work on mutualism, the interaction between species populations that is mutually beneficial, is reviewed. Several ecological facts that should be addressed in the construction of dynamic models for mutualism are examined. Basic terminology is clarified. (PSB)

  7. Phase Two Protected Species Valuation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Nonmarket valuation research has produced economic value estimates for a variety of threatened, endangered, and rare species around the world. Although over 40 value...

  8. 76 FR 1405 - Endangered Species

    Science.gov (United States)

    2011-01-10

    ... the understanding of the pelagic ecology of these species and allow more reliable assessments of... permit: (1) Was applied for in good faith, (2) will not operate to the disadvantage of such endangered or...

  9. Infrared spectra of mineral species

    CERN Document Server

    Chukanov, Nikita V

    2014-01-01

    This book details more than 3,000 IR spectra of more than 2,000 mineral species collected during last 30 years. It features full descriptions and analytical data of each sample for which IR spectrum was obtained.

  10. THE USE OF CASSAVA SPECIES

    African Journals Online (AJOL)

    User

    The plant is propagated from mature stems, which .... USE OF CASSAVA SPECIES AND ALUM IN WASTE WATER TREATMENT, .... acidity, total suspended solids, dissolved oxygen and ..... Rural Areas, MSc Thesis, Department of Water.

  11. Achromobacter species in cystic fibrosis

    DEFF Research Database (Denmark)

    Hansen, C R; Pressler, T; Ridderberg, W

    2013-01-01

    Achromobacter species leads to chronic infection in an increasing number of CF patients. We report 2 cases of Achromobacter ruhlandii cross-infection between patients after well-described indirect contact....

  12. Species Typing in Dermal Leishmaniasis

    Science.gov (United States)

    Dujardin, Jean-Claude

    2015-01-01

    SUMMARY Leishmania is an infectious protozoan parasite related to African and American trypanosomes. All Leishmania species that are pathogenic to humans can cause dermal disease. When one is confronted with cutaneous leishmaniasis, identification of the causative species is relevant in both clinical and epidemiological studies, case management, and control. This review gives an overview of the currently existing and most used assays for species discrimination, with a critical appraisal of the limitations of each technique. The consensus taxonomy for the genus is outlined, including debatable species designations. Finally, a numerical literature analysis is presented that describes which methods are most used in various countries and regions in the world, and for which purposes. PMID:25672782

  13. The Candida Pathogenic Species Complex

    Science.gov (United States)

    Turner, Siobhán A.; Butler, Geraldine

    2014-01-01

    Candida species are the most common causes of fungal infection. Approximately 90% of infections are caused by five species: Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei. Three (C. albicans, C. tropicalis, and C. parapsilosis) belong to the CTG clade, in which the CTG codon is translated as serine and not leucine. C. albicans remains the most commonly isolated but is decreasing relative to the other species. The increasing incidence of C. glabrata is related to its reduced susceptibility to azole drugs. Genome analysis suggests that virulence in the CTG clade is associated with expansion of gene families, particularly of cell wall genes. Similar independent processes took place in the C. glabrata species group. Gene loss and expansion in an ancestor of C. glabrata may have resulted in preadaptations that enabled pathogenicity. PMID:25183855

  14. Phase One Protected Species Valuation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Nonmarket valuation research has produced economic value estimates for a variety of threatened, endangered, and rare species around the world. Although over 40 value...

  15. Theoretical microbial ecology without species

    Science.gov (United States)

    Tikhonov, Mikhail

    2017-09-01

    Ecosystems are commonly conceptualized as networks of interacting species. However, partitioning natural diversity of organisms into discrete units is notoriously problematic and mounting experimental evidence raises the intriguing question whether this perspective is appropriate for the microbial world. Here an alternative formalism is proposed that does not require postulating the existence of species as fundamental ecological variables and provides a naturally hierarchical description of community dynamics. This formalism allows approaching the species problem from the opposite direction. While the classical models treat a world of imperfectly clustered organism types as a perturbation around well-clustered species, the presented approach allows gradually adding structure to a fully disordered background. The relevance of this theoretical construct for describing highly diverse natural ecosystems is discussed.

  16. Species delimitation in the Stenocereus griseus (Cactaceae) species complex reveals a new species, S. huastecorum.

    Science.gov (United States)

    Alvarado-Sizzo, Hernán; Casas, Alejandro; Parra, Fabiola; Arreola-Nava, Hilda Julieta; Terrazas, Teresa; Sánchez, Cristian

    2018-01-01

    The Stenocereus griseus species complex (SGSC) has long been considered taxonomically challenging because the number of taxa belonging to the complex and their geographical boundaries remain poorly understood. Bayesian clustering and genetic distance-based methods were used based on nine microsatellite loci in 377 individuals of three main putative species of the complex. The resulting genetic clusters were assessed for ecological niche divergence and areolar morphology, particularly spination patterns. We based our species boundaries on concordance between genetic, ecological, and morphological data, and were able to resolve four species, three of them corresponding to S. pruinosus from central Mexico, S. laevigatus from southern Mexico, and S. griseus from northern South America. A fourth species, previously considered to be S. griseus and commonly misidentified as S. pruinosus in northern Mexico showed significant genetic, ecological, and morphological differentiation suggesting that it should be considered a new species, S. huastecorum, which we describe here. We show that population genetic analyses, ecological niche modeling, and morphological studies are complementary approaches for delimiting species in taxonomically challenging plant groups such as the SGSC.

  17. Species delimitation in the Stenocereus griseus (Cactaceae species complex reveals a new species, S. huastecorum.

    Directory of Open Access Journals (Sweden)

    Hernán Alvarado-Sizzo

    Full Text Available The Stenocereus griseus species complex (SGSC has long been considered taxonomically challenging because the number of taxa belonging to the complex and their geographical boundaries remain poorly understood. Bayesian clustering and genetic distance-based methods were used based on nine microsatellite loci in 377 individuals of three main putative species of the complex. The resulting genetic clusters were assessed for ecological niche divergence and areolar morphology, particularly spination patterns. We based our species boundaries on concordance between genetic, ecological, and morphological data, and were able to resolve four species, three of them corresponding to S. pruinosus from central Mexico, S. laevigatus from southern Mexico, and S. griseus from northern South America. A fourth species, previously considered to be S. griseus and commonly misidentified as S. pruinosus in northern Mexico showed significant genetic, ecological, and morphological differentiation suggesting that it should be considered a new species, S. huastecorum, which we describe here. We show that population genetic analyses, ecological niche modeling, and morphological studies are complementary approaches for delimiting species in taxonomically challenging plant groups such as the SGSC.

  18. Species selection for smallholder aquaculture

    OpenAIRE

    Brummett, R.E.

    1996-01-01

    Systems for selection of species for smallholder aquaculture are presented. These are: food fits; management decisions; and economic criteria. Food fits suggests categorizing pond food resources into a few categories based loosely on the instrinsic traits of food which effect their selectivity by predators. Using management decision techniques, potential polycultures might also be compared with each other and with monoculture. Under economic criteria (and for species known in local markets), ...

  19. Endangered Lilium Species of Turkey

    Directory of Open Access Journals (Sweden)

    Sevim Demir

    2018-01-01

    Full Text Available Turkey, which is among the major gene centers of the world and has a special place in plant genetic diversity. However, many plant genetic resources, including geophytes, are under genetic erosion because of the environmental and other problems and therefore face with the danger of extinction. Lilium ciliatum is endemic to North East Anatolia. IUCN (International Union for the Conservation of Natural Resources Red List Category of this species is Endangered (EN. Lilium ciliatum naturally grown in Zigana pass, Bayburt, Trabzon, Bulancak, Giresun and Gümüşhane is endangered and major threats of L. ciliatum are road construction and human disturbance related to ecotourism and recreation. It was reported that Lilium carniolicum naturally grown in Turkey is endangered although it isn’t in the IUCN Red List. Distribution areas of L. carniolicum are Trabzon, Rize, Artvin and it is also endemic to North East Anatolia. These species have high potential for use as ornamental plants with their colorful big flowers. In addition, the bulbs of these species are also used in the cosmetic industry and medicine. These are the main properties that increase the importance of L. ciliatum and L. carniolicum species. Therefore it is very important to protect the habitats of these species, ensure the continuity of their generations. The disappearance of these endemic species from our country means to disappear from the world. This review has been given in order to give some information about the endangered Lilium species of Turkey and conservation actions on these species in Turkey flora and take attention to the issue.

  20. Collective behaviour across animal species.

    Science.gov (United States)

    DeLellis, Pietro; Polverino, Giovanni; Ustuner, Gozde; Abaid, Nicole; Macrì, Simone; Bollt, Erik M; Porfiri, Maurizio

    2014-01-16

    We posit a new geometric perspective to define, detect, and classify inherent patterns of collective behaviour across a variety of animal species. We show that machine learning techniques, and specifically the isometric mapping algorithm, allow the identification and interpretation of different types of collective behaviour in five social animal species. These results offer a first glimpse at the transformative potential of machine learning for ethology, similar to its impact on robotics, where it enabled robots to recognize objects and navigate the environment.

  1. Thromboelastography in Selected Avian Species

    DEFF Research Database (Denmark)

    Andersen, Sophie Susanna Strindberg; Nielsen, Tenna W; Ribeiro, Ângela M

    2015-01-01

    Currently available assay methods and reagents are not optimized for evaluating avian hemostasis; therefore, assessing avian coagulopathies is challenging. Recently, thromboelastography (TEG), which measures the viscoelastic properties of blood, has been used clinically in mammalian species...... to diagnose and characterize hemostatic disorders. To evaluate TEG in healthy individuals of 6 avian species, we modified existing mammalian TEG protocols to allow analysis of citrated, avian whole-blood samples collected from scarlet ibis (Eudocimus ruber) (n = 13), American flamingos ( Phoenicopterus ruber...

  2. The nature of plant species.

    Science.gov (United States)

    Rieseberg, Loren H; Wood, Troy E; Baack, Eric J

    2006-03-23

    Many botanists doubt the existence of plant species, viewing them as arbitrary constructs of the human mind, as opposed to discrete, objective entities that represent reproductively independent lineages or 'units of evolution'. However, the discreteness of plant species and their correspondence with reproductive communities have not been tested quantitatively, allowing zoologists to argue that botanists have been overly influenced by a few 'botanical horror stories', such as dandelions, blackberries and oaks. Here we analyse phenetic and/or crossing relationships in over 400 genera of plants and animals. We show that although discrete phenotypic clusters exist in most genera (> 80%), the correspondence of taxonomic species to these clusters is poor (< 60%) and no different between plants and animals. Lack of congruence is caused by polyploidy, asexual reproduction and over-differentiation by taxonomists, but not by contemporary hybridization. Nonetheless, crossability data indicate that 70% of taxonomic species and 75% of phenotypic clusters in plants correspond to reproductively independent lineages (as measured by postmating isolation), and thus represent biologically real entities. Contrary to conventional wisdom, plant species are more likely than animal species to represent reproductively independent lineages.

  3. The Colletotrichum gloeosporioides species complex.

    Science.gov (United States)

    Weir, B S; Johnston, P R; Damm, U

    2012-09-15

    The limit of the Colletotrichum gloeosporioides species complex is defined genetically, based on a strongly supported clade within the Colletotrichum ITS gene tree. All taxa accepted within this clade are morphologically more or less typical of the broadly defined C. gloeosporioides, as it has been applied in the literature for the past 50 years. We accept 22 species plus one subspecies within the C. gloeosporioides complex. These include C. asianum, C. cordylinicola, C. fructicola, C. gloeosporioides, C. horii, C. kahawae subsp. kahawae, C. musae, C. nupharicola, C. psidii, C. siamense, C. theobromicola, C. tropicale, and C. xanthorrhoeae, along with the taxa described here as new, C. aenigma, C. aeschynomenes, C. alatae, C. alienum, C. aotearoa, C. clidemiae, C. kahawae subsp. ciggaro, C. salsolae, and C. ti, plus the nom. nov. C. queenslandicum (for C. gloeosporioides var. minus). All of the taxa are defined genetically on the basis of multi-gene phylogenies. Brief morphological descriptions are provided for species where no modern description is available. Many of the species are unable to be reliably distinguished using ITS, the official barcoding gene for fungi. Particularly problematic are a set of species genetically close to C. musae and another set of species genetically close to C. kahawae, referred to here as the Musae clade and the Kahawae clade, respectively. Each clade contains several species that are phylogenetically well supported in multi-gene analyses, but within the clades branch lengths are short because of the small number of phylogenetically informative characters, and in a few cases individual gene trees are incongruent. Some single genes or combinations of genes, such as glyceraldehyde-3-phosphate dehydrogenase and glutamine synthetase, can be used to reliably distinguish most taxa and will need to be developed as secondary barcodes for species level identification, which is important because many of these fungi are of biosecurity

  4. Terrestrial animals as invasive species and as species at risk from invasions

    Science.gov (United States)

    Deborah M. Finch; Dean Pearson; Joseph Wunderle; Wayne Arendt

    2010-01-01

    Including terrestrial animal species in the invasive species strategy plan is an important step in invasive species management. Invasions by nonindigenous species threaten nearly 50 percent of imperiled native species in the United States and are the Nation's second leading cause of species endangerment. Invasion and conversion of native habitats by exotic species...

  5. Malassezia Species and Pityriasis Versicolor

    Directory of Open Access Journals (Sweden)

    Gulin Rodoplu

    2016-01-01

    Full Text Available Malassezia species are found in part of the normal human cutaneous commensal flora, however it has been known for many years that the Malassezia yeasts are associated with a number of different human diseases ranging from pityriasis versicolor to seborrhoeic dermatitis. In addition, since the 1980s, they have been reported as causing opportunistic systemic infections. The taxonomy of Malassezia spp. has recently been modified to include 13 obligatorily lipophilic species, plus one non-obligatorily lipophilic species, which only rarely colonizes human hosts and currently the genus consist 14 species as M. furfur, M. pachydermatis, M. sympodialis, M. globosa, M. obtusa, M. slooffiae, M. restricta, M. dermatis, M. japonica, M. nana, M. yamatoensis, M. caprae, M. equina, M. cuniculi. Fastidious growth requirements of Malassezia yeasts defied the initial attempts to culture these organisms and their true identification and the relationship between different species only became apparent with the application of modern molecular techniques. The causative fungus is seen especially in such seborrheic areas as the scalp, face, trunk and upper back. Under the influence of various exogenous or endogenous predisposing factors, these yeasts change from the blastospore form to the mycelial form and become pathogenic. Diagnosis of pityriasis versicolor which is caused by Malassezia species is generally easy and lies on the basis of its clinical appearance and can be confirmed by mycological examination. The diagnosisis is mainly based on direct examination with potassium hydroxide (KOH and demonstration that represents pseudohyphae and blastoconidia as the typical %u201Cspaghetti and meatballs%u201D pattern. Characteristic features of the genus Malassezia include a distinctive morphology and an affinity for lipids in culture. Culture is necessary to recover the infecting strain, especially for epidemiologic purposes and also to test its antifungal susceptibility

  6. Phenotypic covariance at species' borders.

    Science.gov (United States)

    Caley, M Julian; Cripps, Edward; Game, Edward T

    2013-05-28

    Understanding the evolution of species limits is important in ecology, evolution, and conservation biology. Despite its likely importance in the evolution of these limits, little is known about phenotypic covariance in geographically marginal populations, and the degree to which it constrains, or facilitates, responses to selection. We investigated phenotypic covariance in morphological traits at species' borders by comparing phenotypic covariance matrices (P), including the degree of shared structure, the distribution of strengths of pair-wise correlations between traits, the degree of morphological integration of traits, and the ranks of matricies, between central and marginal populations of three species-pairs of coral reef fishes. Greater structural differences in P were observed between populations close to range margins and conspecific populations toward range centres, than between pairs of conspecific populations that were both more centrally located within their ranges. Approximately 80% of all pair-wise trait correlations within populations were greater in the north, but these differences were unrelated to the position of the sampled population with respect to the geographic range of the species. Neither the degree of morphological integration, nor ranks of P, indicated greater evolutionary constraint at range edges. Characteristics of P observed here provide no support for constraint contributing to the formation of these species' borders, but may instead reflect structural change in P caused by selection or drift, and their potential to evolve in the future.

  7. Aspergillus fumigatus and Related Species

    Science.gov (United States)

    Sugui, Janyce A.; Kwon-Chung, Kyung J.; Juvvadi, Praveen R.; Latgé, Jean-Paul; Steinbach, William J.

    2015-01-01

    The genus Aspergillus contains etiologic agents of aspergillosis. The clinical manifestations of the disease range from allergic reaction to invasive pulmonary infection. Among the pathogenic aspergilli, Aspergillus fumigatus is most ubiquitous in the environment and is the major cause of the disease, followed by Aspergillus flavus, Aspergillus niger, Aspergillus terreus, Aspergillus nidulans, and several species in the section Fumigati that morphologically resemble A. fumigatus. Patients that are at risk for acquiring aspergillosis are those with an altered immune system. Early diagnosis, species identification, and adequate antifungal therapy are key elements for treatment of the disease, especially in cases of pulmonary invasive aspergillosis that often advance very rapidly. Incorporating knowledge of the basic biology of Aspergillus species to that of the diseases that they cause is fundamental for further progress in the field. PMID:25377144

  8. What is a Species? An Endless Debate

    Indian Academy of Sciences (India)

    Srimath

    a research scholar in ... perspectives are collectively termed as Phylogenetic Species ... tors view the origin of the species they study”. ..... explosion of molecular data has been the major driving force in unearthing cryptic species, it is no ...

  9. Vegetation composition and structure influences bird species ...

    African Journals Online (AJOL)

    Vegetation composition and structure influences bird species community ... variables on bird species diversity and richness of respective foraging guilds, and ... of the species assessed: (1) increasing closed cover due to woody plant density, ...

  10. Alien species recorded in the United Arab Emirates: an initial list of terrestrial and freshwater species

    Directory of Open Access Journals (Sweden)

    Pritpal Soorae

    2015-10-01

    Full Text Available Little is documented on the alien terrestrial and freshwater species in the United Arab Emirates. To address this, an assessment of terrestrial and freshwater alien species was conducted using various techniques such as a questionnaire, fieldwork data, networking with relevant people, and a detailed literature review. The results of the initial assessment show that there are 146 alien species recorded in the following seven major taxonomic groups: invertebrates 49 species, freshwater fish five species, amphibian one species, reptiles six species, birds 71 species, mammals six species and plants eight species. To inform decision makers a full list of the 146 species identified in this assessment is presented. 

  11. Man...An Endangered Species?

    Science.gov (United States)

    Department of the Interior, Washington, DC.

    The general theme of this 1968 yearbook is that man is a threatened species, facing overpopulation and unbridled technology - both self induced. The presentation is broad, relating to many aspects of conservation and natural resources in the United States in a descriptive, non-technical style. The yearbook is divided into major topics: Land…

  12. Phylogenetic relationships among Maloideae species

    Science.gov (United States)

    The Maloideae is a highly diverse sub-family of the Rosaceae containing several agronomically important species (Malus sp. and Pyrus sp.) and their wild relatives. Previous phylogenetic work within the group has revealed extensive intergeneric hybridization and polyploidization. In order to develop...

  13. Botrytis species on bulb crops

    NARCIS (Netherlands)

    Lorbeer, J.W.; Seyb, A.M.; Boer, de M.; Ende, van den J.E.

    2007-01-01

    Abstract. A number of Botrytis species are pathogens of bulb crops. Botrytis squamosa (teleomorph=Botrytotinia squamosa) causal agent of botrytis leaf blight and B. allii the causal agent of botrytis neck rotare two of the most important fungal diseases of onion. The taxonomics of several of the

  14. Endangered Species: An Educator's Handbook.

    Science.gov (United States)

    Smith, Jean, M., Comp.

    Presented are two articles, an annotated bibliography, and other information useful in teaching about endangered species, especially those found in Florida. The articles provide an ethical rationale, teaching suggestions, and a discussion of the value of wildlife. Descriptions of over 100 pertinent books, periodicals, movies, and filmstrips are in…

  15. Molecular Epidemiology of Fonsecaea Species

    NARCIS (Netherlands)

    Najafzadeh, M.J.; Sun, J.; Vicente, V.A.; Klaassen, C.H.W.; Bonifaz, A.; Gerrits van den Ende, A.H.G.; Menken, S.B.J.; de Hoog, G.S.

    2011-01-01

    To assess population diversities among 81 strains of fungi in the genus Fonsecaea that had been identified down to species level, we applied amplified fragment-length polymorphism (AFLP) technology and sequenced the internal transcribed spacer regions and the partial cell division cycle, β-tubulin,

  16. SARS – virus jumps species

    Indian Academy of Sciences (India)

    SARS – virus jumps species. Coronavirus reshuffles genes; Rotteir et al, Rotterdam showed the virus to jump from cats to mouse cells after single gene mutation ? Human disease due to virus jumping from wild or domestic animals; Present favourite animal - the cat; - edible or domestic.

  17. Species recovery in the United States: Increasing the effectiveness of the Endangered Species Act

    Science.gov (United States)

    Daniel M. Evans; Judy P. Che-Castaldo; Deborah Crouse; Frank W. Davis; Rebecca Epanchin-Niell; Curtis H. Flather; R. Kipp Frohlich; Dale D. Goble; Ya-Wei Li; Timothy D. Male; Lawrence L. Master; Matthew P. Moskwik; Maile C. Neel; Barry R. Noon; Camille Parmesan; Mark W. Schwartz; J. Michael Scott; Byron K. Williams

    2016-01-01

    The Endangered Species Act (ESA) has succeeded in shielding hundreds of species from extinction and improving species recovery over time. However, recovery for most species officially protected by the ESA - i.e., listed species - has been harder to achieve than initially envisioned. Threats to species are persistent and pervasive, funding has been insufficient...

  18. Optimal conservation of migratory species.

    Directory of Open Access Journals (Sweden)

    Tara G Martin

    Full Text Available BACKGROUND: Migratory animals comprise a significant portion of biodiversity worldwide with annual investment for their conservation exceeding several billion dollars. Designing effective conservation plans presents enormous challenges. Migratory species are influenced by multiple events across land and sea-regions that are often separated by thousands of kilometres and span international borders. To date, conservation strategies for migratory species fail to take into account how migratory animals are spatially connected between different periods of the annual cycle (i.e. migratory connectivity bringing into question the utility and efficiency of current conservation efforts. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report the first framework for determining an optimal conservation strategy for a migratory species. Employing a decision theoretic approach using dynamic optimization, we address the problem of how to allocate resources for habitat conservation for a Neotropical-Nearctic migratory bird, the American redstart Setophaga ruticilla, whose winter habitat is under threat. Our first conservation strategy used the acquisition of winter habitat based on land cost, relative bird density, and the rate of habitat loss to maximize the abundance of birds on the wintering grounds. Our second strategy maximized bird abundance across the entire range of the species by adding the constraint of maintaining a minimum percentage of birds within each breeding region in North America using information on migratory connectivity as estimated from stable-hydrogen isotopes in feathers. We show that failure to take into account migratory connectivity may doom some regional populations to extinction, whereas including information on migratory connectivity results in the protection of the species across its entire range. CONCLUSIONS/SIGNIFICANCE: We demonstrate that conservation strategies for migratory animals depend critically upon two factors: knowledge of

  19. Synopsis of the Oxyethira flavicornis species group with new Japanese Oxyethira species (Trichoptera, Hydroptilidae

    Directory of Open Access Journals (Sweden)

    Oláh, J.

    2013-06-01

    Full Text Available A brief synopsis of the Oxyethira flavicornis species group is produced by the examination of type materials. Diagrammatic drawings with similar style were prepared for all the known and for the new species. Short description of genus Oxyethira, subgenus Oxyethira, species group of Oxyethira flavicornis are presented together with the description of five species clusters: O. datra new species cluster, O. ecornuta new species cluster, O. flavicornis new species cluster, O. hiroshima new species cluster, O. tiunovae new species cluster. Five new species are described from the O. flavicornis species group: O chitosea sp. n., O. hena sp. n., O. hiroshima sp. n., O. kakida sp. n., O. mekunna sp. n. One new species is described from the Oxyethira grisea species group: Oxyethira ozea sp. n. and two new species from the Oxyethira ramosa species group: Oxyethira miea sp. n., Oxyethira okinawa sp. n.

  20. Floral reward in Ranunculaceae species

    Directory of Open Access Journals (Sweden)

    Bożena Denisow

    2016-04-01

    Full Text Available Floral reward is important in ecological and evolutionary perspectives and essential in pollination biology. For example, floral traits, nectar and pollen features are essential for understanding the functional ecology, the dynamics of pollen transport, competition for pollinator services, and patterns of specialization and generalization in plant–pollinator interactions. We believe to present a synthetic description in the field of floral reward in Ranunculaceae family important in pollination biology and indicating connections between ecological and evolutionary approaches. The links between insect visitors’ behaviour and floral reward type and characteristics exist. Ranunculaceae is a family of aboot 1700 species (aboot 60 genera, distributed worldwide, however the most abundant representatives are in temperate and cool regions of the northern and southern hemispheres. The flowers are usually radially symmetric (zygomorphic and bisexual, but in Aconitum, Aquilegia are bilaterally symmetric (zygomorphic. Most Ranunculaceae flowers offer no nectar, only pollen (e.g., Ranunculus, Adonis vernalis, Thalictrum, but numerous species create trophic niches for different wild pollinators (e.g. Osmia, Megachile, Bombus, Andrena (Denisow et al. 2008. Pollen is a source of protein, vitamins, mineral salts, organic acids and hormones, but the nutritional value varies greatly between different plant species. The pollen production can differ significantly between Ranunculacea species. The mass of pollen produced in anthers differ due to variations in the number of developed anthers. For example, interspecies differences are considerable, 49 anthers are noted in Aquilegia vulgaris, 70 anthers in Ranunculus lanuginosus, 120 in Adonis vernalis. A significant intra-species differences’ in the number of anthers are also noted (e.g. 41 to 61 in Aquilegia vulgaris, 23-45 in Ranunculus cassubicus. Pollen production can be up to 62 kg per ha for Ranunculus acer

  1. Herbarium of the university of malaga (Spain): vascular plants collection.

    Science.gov (United States)

    García-Sánchez, José; Cabezudo, Baltasar

    2013-01-01

    The herbarium of University of Málaga (MGC Herbarium) is formed by four biological collections. The vascular plants collection (MGC-Cormof) is the main collection of the herbarium. MGC-Cormof dataset aims to digitize and publish data associated with over 76.000 specimens deposited in the collection, of which 97.2% of the specimens are identified at species level. Since 2011, the University of Malaga's Central Research Service (SCAI) has been responsible for maintaining the herbariums and the dataset. The collection is growing continuously, with an annual intake of about 1.500 specimens. Nearly 96% of the collection is digitized, by Herbar v3.7.1 software (F. Pando et al. 1996-2011), making over 73.000 specimens accessible through the GBIF network (http://data.gbif.org/datasets/resource/8105/). At present, 247 families and 8.110 taxa, distributed in angiosperms (93.97%), ferns and fern allies (4.89%) and gymnosperms (1.14%), constitute the MGC-Cormof collection. The families and genera best represented in the collection are Compositae, Leguminosae, Gramineae, Labiatae, Caryophyllaceae, Teucrium, Silene, Asplenium, Linaria and Quercus. Most of the specimens are from the Western Mediterranean Region, fundamentally Southern Spain (Andalusia: 82% of specimens) and Northern Morocco (2.17%). Approximately, 63% of the specimens are georeferenced. The identification of the specimens in the collection has been carried out by the plant biology department at the University of Malaga and plus 40% of the specimens has been reviewed by experts. The MGC-Cormof dataset has been revised by DarwinTest v3.2 tool (Ortega-Maqueda and Pando 2008) before being published in GBIF. The data included in this database are important for conservation works, taxonomy, flora, cartography, phenology, palynology, among others. El Herbario de la Universidad de Málaga (Herbario MGC) está constituido por cuatro colecciones biológicas. La colección de plantas vasculares (MGC Cormof) es la colecci

  2. Herbarium of the University of Malaga (Spain: Vascular Plants Collection

    Directory of Open Access Journals (Sweden)

    Jose García Sánchez

    2013-09-01

    Full Text Available The herbarium of University of Málaga (MGC Herbarium is formed by four biological collections. The vascular plants collection (MGC-Cormof is the main collection of the herbarium. MGC-Cormof dataset aims to digitize and publish data associated with over 76.000 specimens deposited in the collection, of which 97.2% of the specimens are identified at species level. Since 2011, the University of Malaga’s Central Research Service (SCAI has been responsible for maintaining the herbariums and the dataset. The collection is growing continuously, with an annual intake of about 1.500 specimens. Nearly 96% of the collection is digitized, by Herbar v3.7.1 software (F. Pando et al. 1996–2011, making over 73.000 specimens accessible through the GBIF network (http://data.gbif.org/datasets/resource/8105/. At present, 247 families and 8.110 taxa, distributed in angiosperms (93.97%, ferns and fern allies (4.89% and gymnosperms (1.14%, constitute the MGC-Cormof collection. The families and genera best represented in the collection are Compositae, Leguminosae, Gramineae, Labiatae, Caryophyllaceae, Teucrium, Silene, Asplenium, Linaria and Quercus. Most of the specimens are from the Western Mediterranean Region, fundamentally Southern Spain (Andalusia: 82% of specimens and Northern Morocco (2.17%. Approximately, 63% of the specimens are georeferenced. The identification of the specimens in the collection has been carried out by the plant biology department at the University of Malaga and plus 40% of the specimens has been reviewed by experts. The MGC-Cormof dataset has been revised by DarwinTest v3.2 tool (Ortega-Maqueda and Pando 2008 before being published in GBIF. The data included in this database are important for conservation works, taxonomy, flora, cartography, phenology, palynology, among others.El Herbario de la Universidad de Málaga (Herbario MGC está constituido por cuatro colecciones biológicas. La colección de plantas vasculares (MGC Cormof es la

  3. Photosynthetic performance of Colobanthus quitensis (Kunth Bartl. (Caryophyllaceae in a high-elevation site of the Andes of central Chile Desempeño fotosintético de Colobanthus quitensis (Kunth Bartl. (Caryophyllaceae en los Andes de Chile central

    Directory of Open Access Journals (Sweden)

    M. ANGÉLICA CASANOVA-KATNY

    2006-03-01

    Full Text Available Photosynthesis of Colobanthus quitensis and mesoclimatic conditions of air temperature and light intensity during the growing season were investigated at 2,650 m in the central Chilean Andes. On three typical days of the growing period (January, March and May, CO2 exchange and chlorophyll fluorescence were measured. In addition, a series of fluorescence response curves with increasing light intensity at different temperatures were performed to estimate the propensity of Andean C. quitensis populations to be photoinhibited. Net Photosynthesis (Pn was low (ca. 2.0 mmol CO2 m-2s-1 during the morning and noon in days with high photosynthetic active radiation (PAR, above 1,800 mmol photons m-2s-1. Pn increased in the afternoon (3.5-4.8 mmol CO2 m-2s-1 when PAR decreased to ca. 1,400 mmol photons m-2s-1 and leaf temperature were ca. 20 °C. Fv/Fm in the diurnal periods was between 0.7-0.75 without evidence of photoinhibition. Leaves at 15 and 22 °C exhibited a slow decrease of F PSII with the increase in actinic light intensity, although the fraction of reaction centers open (expressed by qP remained higher at 22 °C. NPQ was saturated at light intensities close to 500 mmol photons m-2s-1 in leaves at 22 °C and at higher intensities at 15 °C, suggesting that NPQ could be a mechanism of energy dissipation at high light intensity and high leaf temperature in the field. Our results indicated that C. quitensis is not photodamaged during the diurnal cycle and that the low Pn registered during some diurnal periods are likely to be related with photorespiration, which has been suggested as an efficient protective mechanism for photoinhibition in alpine plants. Our results are also compared with the photosynthetic performance of C. quitensis populations from the maritime AntarcticSe estudió la fotosíntesis de Colobanthus quitensis y las condiciones mesoclimáticas de temperatura del aire e intensidad lumínica a 2.650 m en los Andes de Chile central. Se midió la tasa de intercambio gaseoso y la fluorescencia de la clorofila en tres días típicos durante la estación de crecimiento (enero, marzo y mayo. Adicionalmente, se realizaron una serie de curvas de respuesta a incrementos en la intensidad lumínica a diferentes temperaturas para estimar la propensión de C. quitensis a la fotoinhibición. La fotosíntesis neta (Pn fue baja (ca. de 2,0 mmol CO2 m-2s-1 en la mañana y mediodía en días con alta radiación fotosintéticamente activa (PAR, sobre los 1.500 mmol fotones m-2s-1. La tasa de fotosíntesis aumentó en la tarde (3,5-4,8 mmol CO2 m-2s-1 cuando la radiación PAR disminuyó a alrededor de 1.000 mmol fotones m-2s-1. Fv/Fm osciló entre 0,7-0,75 en los registros de enero y marzo, decreciendo en mayo a 0,67. Hojas medidas a 15 y 22 °C mostraron un leve descenso en F PSII con el aumento en la intensidad de luz actínica, aunque la fracción de centros de reacción abiertos (expresados por qP fue mayor a 22 °C. NPQ fue saturado a intensidades lumínicas cercanas a 500 mmol photons m-2s-1 en hojas a 22 °C, y a intensidades mayores en hojas a 15 °C, sugiriendo que NPQ puede ser un mecanismo de disipación energética bajo condiciones de altas intensidades lumínicas y altas temperaturas en el campo. Nuestros resultados indican que C. quitensis no sufre fotodaño durante los ciclos diurnos, y probablemente, los bajos Pn registrados durante algunos periodos diurnos están relacionados con fotorrespiración, la cual ha sido sugerida como un mecanismo muy eficiente en la protección de plantas alpinas contra la fotoinhibición. Nuestros resultados también son comparados con el desempeño fotosintético de las poblaciones de C. quitensis en la Antártica marítima

  4. Tratamento de matrizes de cravo (Dianthus caryophyllus L., Caryophyllaceae com nitrogênio e calogênese in vitro Nitrogen treatment of carnation (Dianthus caryophyllus l., Caryophyllaceae and in vitro calogenesis

    Directory of Open Access Journals (Sweden)

    Telma Kazumi Hayashi

    2002-03-01

    Full Text Available Indução de calogênese eficiente e multiplicação celular rápida são pré-requisitos fundamentais em biotecnologia de plantas. Sucesso na calogênese é dependente dos componentes do meio de cultura e da qualidade dos explantes. Neste trabalho é relatada a influência do tratamento de matrizes de Dianthus caryophyllus L. com nitrogênio na indução de calogênese in vitro. Mudas de cravo cultivadas em vasos contendo areia foram tratadas com soluções nutritivas contendo 5 níveis de nitrogênio. Explantes folha, entrenós e nó foram coletados aos 30, 45 e 60 dias após início dos tratamentos e inoculados em meio de cultura contendo os sais básicos e vitaminas de Murashige & Skoog (1962, suplementado com 1 g L-1 de caseína hidrolizada, 2 mimol L-1 de cinetina e 3 mimol L-1 de 2,4-D para indução da calogênese. Ao longo dos 60 dias de tratamento com as soluções nutritivas, as matrizes de cravo não apresentaram sintomas visíveis de deficiência ou de excesso do nutriente nitrogênio. O tratamento com nitrogênio afetou a calogênese avaliada em massa de matéria fresca e seca. A produção da massa de matéria fresca de calos foi proporcional ao tratamento com nitrogênio até concentração de 267 mg L-1 para explantes folha por durante 30 dias. Tratamentos mais prolongados (45 e 60 dias afetaram negativamente a calogênese e foram inversamente proporcionais a concentração de nitrogênio na solução nutritiva.Efficient calogenesis induction and rapid cell multiplication are fundamental requirements in plant biotechnology. The success of calogenesis is dependent on the growth medium components and the quality of explants. This work is referred to the influence of Dianthus caryophyllus L. nitrogen treatment on calogenesis induction in vitro. Carnation cuts rooted in sand pots were treated with nutrient solutions containing 5 nitrogen levels. Leaves, internodes and node explants were collected and inoculated on callus induction culture media containing Murashige & Skoog (1962 salts and vitamins, supplemented with 1 g L-1 hidrolysed casein, 2 mumol L-1 kinetin and 3 mumol L-1 2,4-D. No plant deficiency and toxicity symptoms were apparent on the treated plants during the 60 day treatment. The nitrogen treatment affected calogenesis in relation to calli fresh and dry weights. Callus fresh weigth yield was proportional to nitrogen concentration up to 267 mg L-1 for leaf explant during 30 days. Longer treatments (45 and 60 days affected calogenesis negatively which were inversely proportional to the nitrogen concentration of the nutrient solution.

  5. ICRAF Species Switchboard. Version 1.2

    DEFF Research Database (Denmark)

    Kindt, R.; Ordonez, J.; Smith, E.

    2015-01-01

    The current version of the Agroforestry Species Switchboard documents the presence of a total of 26,135 plant species (33,813 species including synonyms) across 19 web-based databases. When available, hyperlinks to information on the selected species in particular databases are provided. In total...

  6. Ranking species in mutualistic networks

    Science.gov (United States)

    Domínguez-García, Virginia; Muñoz, Miguel A.

    2015-02-01

    Understanding the architectural subtleties of ecological networks, believed to confer them enhanced stability and robustness, is a subject of outmost relevance. Mutualistic interactions have been profusely studied and their corresponding bipartite networks, such as plant-pollinator networks, have been reported to exhibit a characteristic ``nested'' structure. Assessing the importance of any given species in mutualistic networks is a key task when evaluating extinction risks and possible cascade effects. Inspired in a recently introduced algorithm -similar in spirit to Google's PageRank but with a built-in non-linearity- here we propose a method which -by exploiting their nested architecture- allows us to derive a sound ranking of species importance in mutualistic networks. This method clearly outperforms other existing ranking schemes and can become very useful for ecosystem management and biodiversity preservation, where decisions on what aspects of ecosystems to explicitly protect need to be made.

  7. Competitive intransitivity promotes species coexistence.

    Science.gov (United States)

    Laird, Robert A; Schamp, Brandon S

    2006-08-01

    Using a spatially explicit cellular automaton model with local competition, we investigate the potential for varied levels of competitive intransitivity (i.e., nonhierarchical competition) to promote species coexistence. As predicted, on average, increased levels of intransitivity result in more sustained coexistence within simulated communities, although the outcome of competition also becomes increasingly unpredictable. Interestingly, even a moderate degree of intransitivity within a community can promote coexistence, in terms of both the length of time until the first competitive exclusion and the number of species remaining in the community after 500 simulated generations. These results suggest that modest levels of intransitivity in nature, such as those that are thought to be characteristic of plant communities, can contribute to coexistence and, therefore, community-scale biodiversity. We explore a potential connection between competitive intransitivity and neutral theory, whereby competitive intransitivity may represent an important mechanism for "ecological equivalence."

  8. Charcoal anatomy of forest species

    Directory of Open Access Journals (Sweden)

    Graciela Inés Bolzon de Muñiz1

    2012-09-01

    Full Text Available Vegetal charcoal retains the anatomical structure of the wood and may permit its botanical identification, which depends on species characteristics, the charcoal fragments size and preservation state. Anatomical characterization of ten forest species charcoal was done envisaging the identification and control of illegal charcoal. Differences between gymnosperms and angiosperms are evident in carbonized wood. Vessel diameter was statistically different between wood and charcoal in Vatairea guianensis, Mezilaurus itauba, Calophyllum brasiliense e Qualea cf. acuminata, and vessel frequency in Vatairea guianensis, Manilkara huberi, Qualea cf. acuminata e Simarouba amara. The anatomical structure from wood, in general aspects, is constant during carbonization process using temperature of 450°C, being possible to identify the material by using its cellular components.

  9. Population Genomics of Paramecium Species.

    Science.gov (United States)

    Johri, Parul; Krenek, Sascha; Marinov, Georgi K; Doak, Thomas G; Berendonk, Thomas U; Lynch, Michael

    2017-05-01

    Population-genomic analyses are essential to understanding factors shaping genomic variation and lineage-specific sequence constraints. The dearth of such analyses for unicellular eukaryotes prompted us to assess genomic variation in Paramecium, one of the most well-studied ciliate genera. The Paramecium aurelia complex consists of ∼15 morphologically indistinguishable species that diverged subsequent to two rounds of whole-genome duplications (WGDs, as long as 320 MYA) and possess extremely streamlined genomes. We examine patterns of both nuclear and mitochondrial polymorphism, by sequencing whole genomes of 10-13 worldwide isolates of each of three species belonging to the P. aurelia complex: P. tetraurelia, P. biaurelia, P. sexaurelia, as well as two outgroup species that do not share the WGDs: P. caudatum and P. multimicronucleatum. An apparent absence of global geographic population structure suggests continuous or recent dispersal of Paramecium over long distances. Intergenic regions are highly constrained relative to coding sequences, especially in P. caudatum and P. multimicronucleatum that have shorter intergenic distances. Sequence diversity and divergence are reduced up to ∼100-150 bp both upstream and downstream of genes, suggesting strong constraints imposed by the presence of densely packed regulatory modules. In addition, comparison of sequence variation at non-synonymous and synonymous sites suggests similar recent selective pressures on paralogs within and orthologs across the deeply diverging species. This study presents the first genome-wide population-genomic analysis in ciliates and provides a valuable resource for future studies in evolutionary and functional genetics in Paramecium. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Haemolytic glycoglycerolipids from Gymnodinium species.

    Science.gov (United States)

    Parrish, C C; Bodennec, G; Gentien, P

    1998-03-01

    Glycoglycerolipids derived from microalgae can be a source of biologically active substances including toxins. Such glycolipids were analysed in two isolates of toxic marine dinoflagellates from European waters. The lipids of Gymnodinium mikimotoi contained 17% of monogalactosyl diacylglycerol (MGDG) and digalactosyl diacylglycerol (DGDG), while in Gymnodinium sp. the proportion was 35%. MGDG and DGDG from both species were haemolytic. The major unsaturated fatty acid in both algal glycolipids was 18:5 omega 3.

  11. Chemokines in teleost fish species.

    Science.gov (United States)

    Alejo, Alí; Tafalla, Carolina

    2011-12-01

    Chemokines are chemoattractant cytokines defined by the presence of four conserved cysteine residues which in mammals can be divided into four subfamilies depending on the arrangement of the first two conserved cysteines in their sequence: CXC (α), CC (β), C and CX(3)C classes. Evolutionarily, fish can be considered as an intermediate step between species which possess only innate immunity (invertebrates) and species with a fully developed acquired immune network such as mammals. Therefore, the functionality of their different immune cell types and molecules is sometimes also intermediate between innate and acquired responses. The first chemokine gene identified in a teleost was a rainbow trout (Oncorhynchus mykiss) chemokine designated as CK1 in 1998. Since then, many different chemokine genes have been identified in several fish species, but their role in homeostasis and immune response remains largely unknown. Extensive genomic duplication events and the fact that chemokines evolve more quickly than other immune genes, make it very difficult to establish true orthologues between fish and mammalian chemokines that would help us with the ascription of immune roles. In this review, we describe the current state of knowledge of chemokine biology in teleost fish, focusing mainly on which genes have been identified so far and highlighting the most important aspects of their expression regulation, due to the great lack of functional information available for them. As the number of chemokine genes begins to close down for some teleost species, there is an important need for functional assays that may elucidate the role of each of these molecules within the fish immune response. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Candida Species Biofilms’ Antifungal Resistance

    Science.gov (United States)

    Silva, Sónia; Rodrigues, Célia F.; Araújo, Daniela; Rodrigues, Maria Elisa; Henriques, Mariana

    2017-01-01

    Candida infections (candidiasis) are the most prevalent opportunistic fungal infection on humans and, as such, a major public health problem. In recent decades, candidiasis has been associated to Candida species other than Candida albicans. Moreover, biofilms have been considered the most prevalent growth form of Candida cells and a strong causative agent of the intensification of antifungal resistance. As yet, no specific resistance factor has been identified as the sole responsible for the increased recalcitrance to antifungal agents exhibited by biofilms. Instead, biofilm antifungal resistance is a complex multifactorial phenomenon, which still remains to be fully elucidated and understood. The different mechanisms, which may be responsible for the intrinsic resistance of Candida species biofilms, include the high density of cells within the biofilm, the growth and nutrient limitation, the effects of the biofilm matrix, the presence of persister cells, the antifungal resistance gene expression and the increase of sterols on the membrane of biofilm cells. Thus, this review intends to provide information on the recent advances about Candida species biofilm antifungal resistance and its implication on intensification of the candidiasis. PMID:29371527

  13. Linking Keystone Species and Functional Groups: A New Operational Definition of the Keystone Species Concept

    OpenAIRE

    Robert D. Davic

    2003-01-01

    The concept of the "keystone species" is redefined to allow for the a priori prediction of these species within ecosystems. A keystone species is held to be a strongly interacting species whose top-down effect on species diversity and competition is large relative to its biomass dominance within a functional group. This operational definition links the community importance of keystone species to a specific ecosystem process, e.g., the regulation of species diversity, within functional groups ...

  14. Community structure informs species geographic distributions

    KAUST Repository

    Montesinos-Navarro, Alicia

    2018-05-23

    Understanding what determines species\\' geographic distributions is crucial for assessing global change threats to biodiversity. Measuring limits on distributions is usually, and necessarily, done with data at large geographic extents and coarse spatial resolution. However, survival of individuals is determined by processes that happen at small spatial scales. The relative abundance of coexisting species (i.e. \\'community structure\\') reflects assembly processes occurring at small scales, and are often available for relatively extensive areas, so could be useful for explaining species distributions. We demonstrate that Bayesian Network Inference (BNI) can overcome several challenges to including community structure into studies of species distributions, despite having been little used to date. We hypothesized that the relative abundance of coexisting species can improve predictions of species distributions. In 1570 assemblages of 68 Mediterranean woody plant species we used BNI to incorporate community structure into Species Distribution Models (SDMs), alongside environmental information. Information on species associations improved SDM predictions of community structure and species distributions moderately, though for some habitat specialists the deviance explained increased by up to 15%. We demonstrate that most species associations (95%) were positive and occurred between species with ecologically similar traits. This suggests that SDM improvement could be because species co-occurrences are a proxy for local ecological processes. Our study shows that Bayesian Networks, when interpreted carefully, can be used to include local conditions into measurements of species\\' large-scale distributions, and this information can improve the predictions of species distributions.

  15. HPLC determination of flavonoid glycosides in Mongolian Dianthus versicolor Fisch. (Caryophyllaceae) compared with quantification by UV spectrophotometry.

    Science.gov (United States)

    Obmann, Astrid; Purevsuren, Sodnomtseren; Zehl, Martin; Kletter, Christa; Reznicek, Gottfried; Narantuya, Samdan; Glasl, Sabine

    2012-01-01

    Dianthus versicolor is used in traditional Mongolian medicine against liver impairment. Fractions enriched in flavone-di- and triglycosides were shown to enhance bile secretion. Therefore, reliable and accurate analytical methods are needed for the determination of these flavonoids in the crude drug and extracts thereof. To provide a validated HPLC-DAD (diode array detector) method especially developed for the separation of polar flavonoids and to compare the data obtained with those evaluated by UV spectrophotometry. Separations were carried out on an Aquasil® C₁₈-column (4.6 mm × 250.0 mm, 5 µm) with a linear gradient of acetonitrile and water (adjusted to pH 2.8 with trifluoroacetic acid) as mobile phase. Rutoside was employed as internal standard with linear behavior in a concentration range of 0.007-3.5 mg/mL. Accuracy was determined by spiking the crude drug with saponarin resulting in recoveries between 92% and 102%. The method allows the quantification of highly polar flavonoid glycosides and the determination of their total content. For saponarin a linear response was evaluated within the range 0.007-3.5 mg/mL (R²  > 0.9999). It was proven that threefold sonication represents a time-saving, effective and cheap method for the extraction of the polar flavonoid glycosides. The contents determined by HPLC were shown to be in agreement with those obtained employing UV spectrophotometry. The study has indicated that the newly developed HPLC method represents a powerful technique for the quality control of D. versicolor. Ultraviolet spectrophotometry may be used alternatively provided that the less polar flavonoids are removed by purification. Copyright © 2011 John Wiley & Sons, Ltd.

  16. Epigenetic contribution to successful polyploidizations: variation in global cytosine methylation along an extensive ploidy series in Dianthus broteri (Caryophyllaceae).

    Science.gov (United States)

    Alonso, Conchita; Balao, Francisco; Bazaga, Pilar; Pérez, Ricardo

    2016-11-01

    Polyploidization is a significant evolutionary force in plants which involves major genomic and genetic changes, frequently regulated by epigenetic factors. We explored whether natural polyploidization in Dianthus broteri complex resulted in substantial changes in global DNA cytosine methylation associated to ploidy. Global cytosine methylation was estimated by high-performance liquid chromatography (HPLC) in 12 monocytotypic populations with different ploidies (2×, 4×, 6×, 12×) broadly distributed within D. broteri distribution range. The effects of ploidy level and local variation on methylation were assessed by generalized linear mixed models (GLMMs). Dianthus broteri exhibited a higher methylation percent (˜33%) than expected by its monoploid genome size and a large variation among study populations (range: 29.3-35.3%). Global methylation tended to increase with ploidy but did not significantly differ across levels due to increased variation within the highest-order polyploidy categories. Methylation varied more among hexaploid and dodecaploid populations, despite such cytotypes showing more restricted geographic location and increased genetic relatedness than diploids and tetraploids. In this study, we demonstrate the usefulness of an HPLC method in providing precise and genome reference-free global measure of DNA cytosine methylation, suitable to advance current knowledge of the roles of this epigenetic mechanism in polyploidization processes. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  17. Fitness drivers in the threatened Dianthus guliae Janka (Caryophyllaceae): disentangling effects of growth context, maternal influence and inbreeding depression.

    Science.gov (United States)

    Gargano, D; Gullo, T; Bernardo, L

    2011-01-01

    We studied inbreeding depression, growth context and maternal influence as constraints to fitness in the self-compatible, protandrous Dianthus guliae Janka, a threatened Italian endemic. We performed hand-pollinations to verify outcomes of self- and cross-fertilisation over two generations, and grew inbred and outbred D. guliae offspring under different conditions - in pots, a common garden and field conditions (with/without nutrient addition). The environment influenced juvenile growth and flowering likelihood/rate, but had little effect on inbreeding depression. Significant interactions among genetic and environmental factors influenced female fertility. Overall, genetic factors strongly affected both early (seed mass, seed germination, early survival) and late (seed/ovule ratio) life-history traits. After the first pollination experiment, we detected higher mortality in the selfed progeny, which is possibly a consequence of inbreeding depression caused by over-expression of early-acting deleterious alleles. The second pollination induced a strong loss of reproductive fitness (seed production, seed mass) in inbred D. guliae offspring, regardless of the pollination treatment (selfing/crossing); hence, a strong (genetic) maternal influence constrained early life-history traits of the second generation. Based on current knowledge, we conclude that self-compatibility does not prevent the detrimental effects of inbreeding in D. guliae populations, and may increase the severe extinction risk if out-crossing rates decrease. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.

  18. Alien species in the Finnish weed flora

    Directory of Open Access Journals (Sweden)

    T. HYVÖNEN

    2008-12-01

    Full Text Available The present study aimed at assessing the invasion of alien weed species in Finland based on a review of their occurrence in the Finnish weed flora. The evaluation was conducted for the three phases of the invasion process, i.e. introduction, naturalization and invasion. The literature review revealed that 815 alien weed species occur in Finland of which 314 are regarded as naturalized. Based on their occurrence in different climate zones, the risk of naturalization of new harmful alien weed species was deemed low for those species not currently found in Finland, but higher for species occurring as casual aliens in Finland. In the latter group, 10 species of concern were detected. Exploration of the distribution patterns of naturalized species within Finland revealed species occupancy to be dependent on the residence time of the species. Established neophytes can be expected to extend their ranges and to increase occupation of agricultural habitats in the future.;

  19. Natural Constraints to Species Diversification.

    Directory of Open Access Journals (Sweden)

    Eric Lewitus

    2016-08-01

    Full Text Available Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric approach and 214 family-level phylogenies of vertebrates representing over 500 million years of evolution to identify major diversification modes, to characterize phylogenetic space, and to evaluate the bounds and central tendencies of species diversification. We identify five principal patterns of diversification to which all vertebrate families hold. These patterns, mapped onto multidimensional space, constitute a phylogenetic space with distinct properties. Firstly, phylogenetic space occupies only a portion of all possible tree space, showing family-level phylogenies to be constrained to a limited range of diversification patterns. Secondly, the geometry of phylogenetic space is delimited by quantifiable trade-offs in tree size and the heterogeneity and stem-to-tip distribution of branching events. These trade-offs are indicative of the instability of certain diversification patterns and effectively bound speciation rates (for successful clades within upper and lower limits. Finally, both the constrained range and geometry of phylogenetic space are established by the differential effects of macroevolutionary processes on patterns of diversification. Given these properties, we show that the average path through phylogenetic space over evolutionary time traverses several diversification stages, each of which is defined by a different principal pattern of diversification and directed by a different macroevolutionary process. The identification of universal patterns and natural constraints to diversification provides a foundation for understanding the

  20. Natural Constraints to Species Diversification.

    Science.gov (United States)

    Lewitus, Eric; Morlon, Hélène

    2016-08-01

    Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric approach and 214 family-level phylogenies of vertebrates representing over 500 million years of evolution to identify major diversification modes, to characterize phylogenetic space, and to evaluate the bounds and central tendencies of species diversification. We identify five principal patterns of diversification to which all vertebrate families hold. These patterns, mapped onto multidimensional space, constitute a phylogenetic space with distinct properties. Firstly, phylogenetic space occupies only a portion of all possible tree space, showing family-level phylogenies to be constrained to a limited range of diversification patterns. Secondly, the geometry of phylogenetic space is delimited by quantifiable trade-offs in tree size and the heterogeneity and stem-to-tip distribution of branching events. These trade-offs are indicative of the instability of certain diversification patterns and effectively bound speciation rates (for successful clades) within upper and lower limits. Finally, both the constrained range and geometry of phylogenetic space are established by the differential effects of macroevolutionary processes on patterns of diversification. Given these properties, we show that the average path through phylogenetic space over evolutionary time traverses several diversification stages, each of which is defined by a different principal pattern of diversification and directed by a different macroevolutionary process. The identification of universal patterns and natural constraints to diversification provides a foundation for understanding the deep-time evolution of

  1. Natural Constraints to Species Diversification

    Science.gov (United States)

    Lewitus, Eric; Morlon, Hélène

    2016-01-01

    Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric approach and 214 family-level phylogenies of vertebrates representing over 500 million years of evolution to identify major diversification modes, to characterize phylogenetic space, and to evaluate the bounds and central tendencies of species diversification. We identify five principal patterns of diversification to which all vertebrate families hold. These patterns, mapped onto multidimensional space, constitute a phylogenetic space with distinct properties. Firstly, phylogenetic space occupies only a portion of all possible tree space, showing family-level phylogenies to be constrained to a limited range of diversification patterns. Secondly, the geometry of phylogenetic space is delimited by quantifiable trade-offs in tree size and the heterogeneity and stem-to-tip distribution of branching events. These trade-offs are indicative of the instability of certain diversification patterns and effectively bound speciation rates (for successful clades) within upper and lower limits. Finally, both the constrained range and geometry of phylogenetic space are established by the differential effects of macroevolutionary processes on patterns of diversification. Given these properties, we show that the average path through phylogenetic space over evolutionary time traverses several diversification stages, each of which is defined by a different principal pattern of diversification and directed by a different macroevolutionary process. The identification of universal patterns and natural constraints to diversification provides a foundation for understanding the deep-time evolution of

  2. The Invasive Species Forecasting System

    Science.gov (United States)

    Schnase, John; Most, Neal; Gill, Roger; Ma, Peter

    2011-01-01

    The Invasive Species Forecasting System (ISFS) provides computational support for the generic work processes found in many regional-scale ecosystem modeling applications. Decision support tools built using ISFS allow a user to load point occurrence field sample data for a plant species of interest and quickly generate habitat suitability maps for geographic regions of management concern, such as a national park, monument, forest, or refuge. This type of decision product helps resource managers plan invasive species protection, monitoring, and control strategies for the lands they manage. Until now, scientists and resource managers have lacked the data-assembly and computing capabilities to produce these maps quickly and cost efficiently. ISFS focuses on regional-scale habitat suitability modeling for invasive terrestrial plants. ISFS s component architecture emphasizes simplicity and adaptability. Its core services can be easily adapted to produce model-based decision support tools tailored to particular parks, monuments, forests, refuges, and related management units. ISFS can be used to build standalone run-time tools that require no connection to the Internet, as well as fully Internet-based decision support applications. ISFS provides the core data structures, operating system interfaces, network interfaces, and inter-component constraints comprising the canonical workflow for habitat suitability modeling. The predictors, analysis methods, and geographic extents involved in any particular model run are elements of the user space and arbitrarily configurable by the user. ISFS provides small, lightweight, readily hardened core components of general utility. These components can be adapted to unanticipated uses, are tailorable, and require at most a loosely coupled, nonproprietary connection to the Web. Users can invoke capabilities from a command line; programmers can integrate ISFS's core components into more complex systems and services. Taken together, these

  3. Why some plant species are rare.

    Science.gov (United States)

    Wieger Wamelink, G W; Wamelink, G W Weiger; Goedhart, Paul W; Frissel, Joep; Frissel, Josep Y

    2014-01-01

    Biodiversity, including plant species diversity, is threatened worldwide as a result of anthropogenic pressures such as an increase of pollutants and climate change. Rare species in particular are on the verge of becoming extinct. It is still unclear as to why some plant species are rare and others are not. Are they rare due to: intrinsic reasons, dispersal capacity, the effects of management or abiotic circumstances? Habitat preference of rare plant species may play an important role in determining why some species are rare. Based on an extensive data set of soil parameters we investigated if rarity is due to a narrow habitat preference for abiotic soil parameters. For 23 different abiotic soil parameters, of which the most influential were groundwater-table, soil-pH and nutrient-contents, we estimated species responses for common and rare species. Based on the responses per species we calculated the range of occurrence, the range between the 5 and 95 percentile of the response curve giving the habitat preference. Subsequently, we calculated the average response range for common and rare species. In addition, we designed a new graphic in order to provide a better means for presentation of the results. The habitat preferences of rare species for abiotic soil conditions are significantly narrower than for common species. Twenty of the twenty-three abiotic parameters showed on average significantly narrower habitat preferences for rare species than for common species; none of the abiotic parameters showed on average a narrower habitat preference for common species. The results have major implications for the conservation of rare plant species; accordingly management and nature development should be focussed on the maintenance and creation of a broad range of environmental conditions, so that the requirements of rare species are met. The conservation of (abiotic) gradients within ecosystems is particularly important for preserving rare species.

  4. SIS - Species and Stock Administrative Data Set

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Species and Stock Administrative data set within the Species Information System (SIS) defines entities within the database that serve as the basis for recording...

  5. Assessing Pesticides under the Endangered Species Act

    Science.gov (United States)

    EPA’s pesticide risk assessment and regulatory processes ensure that protections are in place for all populations of non-target species. We have developed risk assessment procedures to determine potential for harm to individuals of a listed species.

  6. Molecular Diagnosis of Pathogenic Sporothrix Species

    NARCIS (Netherlands)

    Rodrigues, Anderson Messias; de Hoog, G Sybren; de Camargo, Zoilo Pires

    2015-01-01

    BACKGROUND: Sporotrichosis is a chronic (sub)cutaneous infection caused by thermodimorphic fungi in the order, Ophiostomatales. These fungi are characterized by major differences in routes of transmission, host predilections, species virulence, and susceptibilities to antifungals. Sporothrix species

  7. 76 FR 68776 - Invasive Species Advisory Committee

    Science.gov (United States)

    2011-11-07

    ... broad array of issues related to preventing the introduction of invasive species and providing for their...-2012 Invasive Species National Management Plan. The meeting is open to the public. An orientation...

  8. Species coextinctions and the biodiversity crisis.

    Science.gov (United States)

    Koh, Lian Pin; Dunn, Robert R; Sodhi, Navjot S; Colwell, Robert K; Proctor, Heather C; Smith, Vincent S

    2004-09-10

    To assess the coextinction of species (the loss of a species upon the loss of another), we present a probabilistic model, scaled with empirical data. The model examines the relationship between coextinction levels (proportion of species extinct) of affiliates and their hosts across a wide range of coevolved interspecific systems: pollinating Ficus wasps and Ficus, parasites and their hosts, butterflies and their larval host plants, and ant butterflies and their host ants. Applying a nomographic method based on mean host specificity (number of host species per affiliate species), we estimate that 6300 affiliate species are "coendangered" with host species currently listed as endangered. Current extinction estimates need to be recalibrated by taking species coextinctions into account.

  9. 77 FR 23740 - Invasive Species Advisory Committee

    Science.gov (United States)

    2012-04-20

    ... broad array of issues related to preventing the introduction of invasive species and providing for their... both ecological and management contexts, will center on topics that: (1) Pertain to invasive species...

  10. Endangered species toxicity extrapolation using ICE models

    Science.gov (United States)

    The National Research Council’s (NRC) report on assessing pesticide risks to threatened and endangered species (T&E) included the recommendation of using interspecies correlation models (ICE) as an alternative to general safety factors for extrapolating across species. ...

  11. Foliar flavonoids of nine species of Bauhinia

    OpenAIRE

    SALATINO, ANTONIO; BLATT, CECÍLIA T.T.; SANTOS, DÉBORAH Y.A.C. DOS; VAZ, ANGELA M.S.F.

    1999-01-01

    Foliar flavonoids of nine species of Bauhinia were isolated and identified. All the compounds correspond to glycosides derived from kaempferol, quercetin, isorhamnetin and myricetin. Derivatives of the latter aglyconhe seem to be rare in Bauhinia. Derivatives of isorhamnetin are commonly found in species of subgenus Bauhinia and were not detected in the two species of subgenus Phanera. Flavonoid patterns of species of the former subgenus are in general more complex than those of the latter. ...

  12. New species of Cystolepiota from China

    Directory of Open Access Journals (Sweden)

    Meng-Lin Xu

    2016-10-01

    Full Text Available In this paper, a new species, Cystolepiota pseudofumosifolia, is introduced. C. pseudofumosifolia is characterized by granulose or powdery pileus with an anatomic structure that is loosely globose, as well as ellipsoid cells in chains in the pileus covering the cheilocystidia. This new species is compared to the related and similar Cystolepiota species in morphology and molecular phylogeny based on Internal transcribed spacer sequences. Both types of data support our specimens as a new species in the genus Cystolepiota.

  13. Linking Keystone Species and Functional Groups: A New Operational Definition of the Keystone Species Concept

    Directory of Open Access Journals (Sweden)

    Robert D. Davic

    2003-07-01

    Full Text Available The concept of the "keystone species" is redefined to allow for the a priori prediction of these species within ecosystems. A keystone species is held to be a strongly interacting species whose top-down effect on species diversity and competition is large relative to its biomass dominance within a functional group. This operational definition links the community importance of keystone species to a specific ecosystem process, e.g., the regulation of species diversity, within functional groups at lower trophic levels that are structured by competition for a limited resource. The a priori prediction of keystone species has applied value for the conservation of natural areas.

  14. Biodiversity in the cyclic competition system of three species according to the emergence of mutant species

    Science.gov (United States)

    Park, Junpyo

    2018-05-01

    Understanding mechanisms which promote or hinder existing ecosystems are important issues in ecological sciences. In addition to fundamental interactions such as competition and migration among native species, existing ecosystems can be easily disturbed by external factors, and the emergence of new species may be an example in such cases. The new species which does not exist in a current ecosystem can be regarded as either alien species entered from outside or mutant species born by mutation in existing normal species. Recently, as existing ecosystems are getting influenced by various physical/chemical external factors, mutation due to anthropogenic and environmental factors can occur more frequently and is thus attracting much attention for the maintenance of ecosystems. In this paper, we consider emergences of mutant species among self-competing three species in the cyclic dominance. By defining mutation as the birth of mutant species, we investigate how mutant species can affect biodiversity in the existing ecosystem. Through microscopic and macroscopic approaches, we have found that the society of existing normal species can be disturbed by mutant species either the society is maintained accompanying with the coexistence of all species or jeopardized by occupying of mutant species. Due to the birth of mutant species, the existing society may be more complex by constituting two different groups of normal and mutant species, and our results can be contributed to analyze complex ecosystems of many species. We hope our findings may propose a new insight on mutation in cyclic competition systems of many species.

  15. Unimodal models to relate species to environment

    NARCIS (Netherlands)

    Braak, ter C.J.F.

    1987-01-01

    To assess the impact of environmental change on biological communities knowledge about species-environment relationships is indispensable. Ecologists attempt to uncover the relationships between species and environment from data obtained from field surveys. In the survey, species are scored on their

  16. 3 CFR - The Endangered Species Act

    Science.gov (United States)

    2010-01-01

    ... 3 The President 1 2010-01-01 2010-01-01 false The Endangered Species Act Presidential Documents Other Presidential Documents Memorandum of March 3, 2009 The Endangered Species Act Memorandum for the Heads of Executive Departments and Agencies The Endangered Species Act (ESA), 16 U.S.C. 1531 et seq...

  17. 75 FR 29359 - Invasive Species Advisory Committee

    Science.gov (United States)

    2010-05-25

    ... Council is co-chaired by the Secretary of the Interior, the Secretary of Agriculture, and the Secretary of... of the most invaded marine/coastal environments in the world, with over 50 invasive species that... development of state invasive species councils. DATES: Meeting of the Invasive Species Advisory Committee...

  18. Endangered Species & Biodiversity: A Classroom Project & Theme

    Science.gov (United States)

    Lauro, Brook

    2012-01-01

    Students discover the factors contributing to species losses worldwide by conducting a project about endangered species as a component of a larger classroom theme of biodiversity. Groups conduct research using online endangered- species databases and present results to the class using PowerPoint. Students will improve computer research abilities…

  19. The Gilbertiodendron ogoouense species complex (Leguminosae

    NARCIS (Netherlands)

    Burgt, van der X.M.; Mackinder, B.A.; Wieringa, J.J.; Estrella, de la Manuel

    2015-01-01

    The Gilbertiodendron ogoouense species complex consists of 14 tree species. Eight species are here newly described and one is here reinstated: G. bambolense Burgt; G. breteleri Burgt; G. ebo Burgt & Mackinder; G. ecoukense (Pellegr.) Burgt; G. maximum Burgt & Wieringa; G. minkebense Burgt

  20. Brachyspira Species and Gastroenteritis in Humans

    NARCIS (Netherlands)

    Westerman, L.J.; Boer, de R.F.; Roelfsema, J.H.; Friesema, I.H.M.; Kortbeek, L.M.; Wagenaar, J.A.; Bonten, M.J.M.; Kusters, J.G.

    2013-01-01

    Brachyspira species have been implicated as a potential cause of gastroenteritis in humans; this is, however, controversial. In 733 gastroenteritis cases and 464 controls, we found 29 samples positive for Brachyspira species (2.3% of cases and 2.6% of controls; P = 0.77). Brachyspira species were

  1. Brachyspira Species and Gastroenteritis in Humans

    NARCIS (Netherlands)

    Westerman, L J; de Boer, R F; Roelfsema, J H; Friesema, I H M; Kortbeek, L M; Wagenaar, J A; Bonten, M J M; Kusters, J G

    Brachyspira species have been implicated as a potential cause of gastroenteritis in humans; this is, however, controversial. In 733 gastroenteritis cases and 464 controls, we found 29 samples positive for Brachyspira species (2.3% of cases and 2.6% of controls; P = 0.77). Brachyspira species were

  2. 22 CFR 216.5 - Endangered species.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Endangered species. 216.5 Section 216.5 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ENVIRONMENTAL PROCEDURES § 216.5 Endangered species. It is A... endangered or threatened species and their critical habitats. The Initial Environmental Examination for each...

  3. Invasive Species Science Update (No. 7)

    Science.gov (United States)

    Dean Pearson; Yvette Ortega; Jack Butler

    2014-01-01

    Invasive Species Science Updates are designed to keep managers and other users up-to-date with recently completed and ongoing research by RMRS scientists, as well as highlight breaking news related to invasive species issues. The newsletter is produced by the RMRS Invasive Species Working Group (ISWG), which is a core group of scientists who volunteer to coordinate...

  4. Do invasive plant species alter soil health?

    Science.gov (United States)

    Invasive species may alter soil characteristics or interact with the soil microbial community to yield a competitive advantage. Our objectives were to determine: if invasive plant species alter soil properties important to soil health; and the long-term effects of invasive plant species on soil pro...

  5. Options in dealing with marine alien species

    NARCIS (Netherlands)

    Pelt-Heerschap, van H.M.L.; Sneekes, A.C.; Foekema, E.M.

    2015-01-01

    Invasive species can have strong impact on the local ecosystem, not only substantial impact on the local ecosystem, but also on economy and human health. This review on marine alien species outlines aspects of prevention, eradication and control strategies. When managing invasive species, prevention

  6. Species rarity: definition, causes, and classification

    Science.gov (United States)

    Curtis H. Flather; Carolyn Hull Sieg

    2007-01-01

    In virtually all ecological communities around the world, most species are represented by few individuals, and most individuals come from only a few of the most common species. Why this distribution of species abundances is so regularly observed among different taxonomic sets in geographically diverse systems is a question that has received considerable theoretical and...

  7. New french uranium mineral species

    International Nuclear Information System (INIS)

    Branche, G.; Chervet, J.; Guillemin, C.

    1952-01-01

    In this work, the authors study the french new uranium minerals: parsonsite and renardite, hydrated phosphates of lead and uranium; kasolite: silicate hydrated of uranium and lead uranopilite: sulphate of uranium hydrated; bayleyite: carbonate of uranium and of hydrated magnesium; β uranolite: silicate of uranium and of calcium hydrated. For all these minerals, the authors give the crystallographic, optic characters, and the quantitative chemical analyses. On the other hand, the following species, very rare in the french lodgings, didn't permit to do quantitative analyses. These are: the lanthinite: hydrated uranate oxide; the α uranotile: silicate of uranium and of calcium hydrated; the bassetite: uranium phosphate and of hydrated iron; the hosphuranylite: hydrated uranium phosphate; the becquerelite: hydrated uranium oxide; the curite: oxide of uranium and lead hydrated. Finally, the authors present at the end of this survey a primary mineral: the brannerite, complex of uranium titanate. (author) [fr

  8. Satellite tracking of threatened species

    Science.gov (United States)

    Williams, M.; Lunsford, A.; Ellis, D.; Robinson, J.; Coronado, P.; Campbell, W.

    1998-01-01

    In 1990, a joint effort of two U.S. federal agencies, NASA Goddard Space Flight Center (GSFC) and the Patuxent Wildlife Research Center, began. We initially joined forces in a project that used satellite telemetry to discover the winter home of a tiny dwindling population of Siberian Cranes. Since then several projects have emerged, and a web site was created to follow some of these activities. This web site is called the Satellite Tracking of Threatened Species and its location is http://sdcd.gsfc.nasa.gov/ISTO/satellite_tracking. It describes the overall program, and links you to three subsections that describe the projects in more detail: Satellite Direct Readout, Birdtracks, and Birdworld.

  9. Ensemble forecasting of species distributions.

    Science.gov (United States)

    Araújo, Miguel B; New, Mark

    2007-01-01

    Concern over implications of climate change for biodiversity has led to the use of bioclimatic models to forecast the range shifts of species under future climate-change scenarios. Recent studies have demonstrated that projections by alternative models can be so variable as to compromise their usefulness for guiding policy decisions. Here, we advocate the use of multiple models within an ensemble forecasting framework and describe alternative approaches to the analysis of bioclimatic ensembles, including bounding box, consensus and probabilistic techniques. We argue that, although improved accuracy can be delivered through the traditional tasks of trying to build better models with improved data, more robust forecasts can also be achieved if ensemble forecasts are produced and analysed appropriately.

  10. Core-satellite species hypothesis and native versus exotic species in secondary succession

    Science.gov (United States)

    Martinez, Kelsey A.; Gibson, David J.; Middleton, Beth A.

    2015-01-01

    A number of hypotheses exist to explain species’ distributions in a landscape, but these hypotheses are not frequently utilized to explain the differences in native and exotic species distributions. The core-satellite species (CSS) hypothesis predicts species occupancy will be bimodally distributed, i.e., many species will be common and many species will be rare, but does not explicitly consider exotic species distributions. The parallel dynamics (PD) hypothesis predicts that regional occurrence patterns of exotic species will be similar to native species. Together, the CSS and PD hypotheses may increase our understanding of exotic species’ distribution relative to natives. We selected an old field undergoing secondary succession to study the CSS and PD hypotheses in conjunction with each other. The ratio of exotic to native species (richness and abundance) was observed through 17 years of secondary succession. We predicted species would be bimodally distributed and that exotic:native species ratios would remain steady or decrease through time under frequent disturbance. In contrast to the CSS and PD hypotheses, native species occupancies were not bimodally distributed at the site, but exotic species were. The exotic:native species ratios for both richness (E:Nrichness) and abundance (E:Ncover) generally decreased or remained constant throughout supporting the PD hypothesis. Our results suggest exotic species exhibit metapopulation structure in old field landscapes, but that metapopulation structures of native species are disrupted, perhaps because these species are dispersal limited in the fragmented landscape.

  11. The nuclear question: rethinking species importance in multi-species animal groups.

    Science.gov (United States)

    Srinivasan, Umesh; Raza, Rashid Hasnain; Quader, Suhel

    2010-09-01

    1. Animals group for various benefits, and may form either simple single-species groups, or more complex multi-species associations. Multi-species groups are thought to provide anti-predator and foraging benefits to participant individuals. 2. Despite detailed studies on multi-species animal groups, the importance of species in group initiation and maintenance is still rated qualitatively as 'nuclear' (maintaining groups) or 'attendant' (species following nuclear species) based on species-specific traits. This overly simplifies and limits understanding of inherently complex associations, and is biologically unrealistic, because species roles in multi-species groups are: (i) likely to be context-specific and not simply a fixed species property, and (ii) much more variable than this dichotomy indicates. 3. We propose a new view of species importance (measured as number of inter-species associations), along a continuum from 'most nuclear' to 'least nuclear'. Using mixed-species bird flocks from a tropical rainforest in India as an example, we derive inter-species association measures from randomizations on bird species abundance data (which takes into account species 'availability') and data on 86 mixed-species flocks from two different flock types. Our results show that the number and average strength of inter-species associations covary positively, and we argue that species with many, strong associations are the most nuclear. 4. From our data, group size and foraging method are ecological and behavioural traits of species that best explain nuclearity in mixed-species bird flocks. Parallels have been observed in multi-species fish shoals, in which group size and foraging method, as well as diet, have been shown to correlate with nuclearity. Further, the context in which multi-species groups occur, in conjunction with species-specific traits, influences the role played by a species in a multi-species group, and this highlights the importance of extrinsic factors in

  12. Ecological impacts of non-native species

    Science.gov (United States)

    Wilkinson, John W.

    2012-01-01

    Non-native species are considered one of the greatest threats to freshwater biodiversity worldwide (Drake et al. 1989; Allen and Flecker 1993; Dudgeon et al. 2005). Some of the first hypotheses proposed to explain global patterns of amphibian declines included the effects of non-native species (Barinaga 1990; Blaustein and Wake 1990; Wake and Morowitz 1991). Evidence for the impact of non-native species on amphibians stems (1) from correlative research that relates the distribution or abundance of a species to that of a putative non-native species, and (2) from experimental tests of the effects of a non-native species on survival, growth, development or behaviour of a target species (Kats and Ferrer 2003). Over the past two decades, research on the effects of non-native species on amphibians has mostly focused on introduced aquatic predators, particularly fish. Recent research has shifted to more complex ecological relationships such as influences of sub-lethal stressors (e.g. contaminants) on the effects of non-native species (Linder et al. 2003; Sih et al. 2004), non-native species as vectors of disease (Daszak et al. 2004; Garner et al. 2006), hybridization between non-natives and native congeners (Riley et al. 2003; Storfer et al. 2004), and the alteration of food-webs by non-native species (Nystrom et al. 2001). Other research has examined the interaction of non-native species in terms of facilitation (i.e. one non-native enabling another to become established or spread) or the synergistic effects of multiple non-native species on native amphibians, the so-called invasional meltdown hypothesis (Simerloff and Von Holle 1999). Although there is evidence that some non-native species may interact (Ricciardi 2001), there has yet to be convincing evidence that such interactions have led to an accelerated increase in the number of non-native species and cumulative impacts are still uncertain (Simberloff 2006). Applied research on the control, eradication, and

  13. Evolution of sex determination systems with heterogametic males and females in Silene

    Czech Academy of Sciences Publication Activity Database

    Šlancarová, Veronika; Ždánská, Jana; Janoušek, Bohuslav; Talianová, Martina; Zschach, C.; Žlůvová, Jitka; Široký, Jiří; Kováčová, Viera; Blavet, Hana; Danihelka, J.; Oxelman, B.; Widmer, A.; Vyskot, Boris

    2013-01-01

    Roč. 67, č. 12 (2013), s. 3669-3677 ISSN 0014-3820 R&D Projects: GA ČR(CZ) GA13-06264S; GA ČR(CZ) GAP501/10/0102; GA ČR(CZ) GBP501/12/G090; GA ČR(CZ) GAP501/12/2220 Institutional support: RVO:68081707 Keywords : ANCESTRAL CHARACTER STATES * MAXIMUM-LIKELIHOOD * DETERMINATION PATHWAY Subject RIV: BO - Biophysics Impact factor: 4.659, year: 2013

  14. Strong Accumulation of Chloroplast DNA in the Y Chromosomes of Rumex acetosa and Silene latifolia

    Czech Academy of Sciences Publication Activity Database

    Šteflová, Pavlína; Hobza, Roman; Vyskot, Boris; Kejnovský, Eduard

    2014-01-01

    Roč. 142, č. 1 (2014), s. 59-65 ISSN 1424-8581 R&D Projects: GA ČR(CZ) GAP305/10/0930; GA ČR(CZ) GAP501/10/0102; GA ČR(CZ) GBP501/12/G090; GA ČR GAP501/12/2220; GA ČR(CZ) GA522/09/0083; GA MŠk(CZ) LO1204 Institutional research plan: CEZ:AV0Z50040702 Institutional support: RVO:68081707 Keywords : Chloroplast DNA * Rumex acetosa * Sex chromosomes Subject RIV: BO - Biophysics Impact factor: 1.561, year: 2014

  15. Kebutuhan Fisur Silen Gigi Posterior pada Murid-Murid Sekolah Dasar di Kota Madya Medan

    Directory of Open Access Journals (Sweden)

    Lina Natamiharja

    2015-10-01

    Full Text Available The application of pit and fissure sealants is widely accepted practice in carious prevention, these materials were developed in an effort to prevent plaque, bacteria and carbohydrates penetrating pits and fissures of the teeth. Fissure sealants are effective in preventing occlusal carious in 33 out of every 100 teeth. The purpose of this study was to determine the needs of fissure sealant among the children age 6-13 years old. This study was carried out in two elementary schools. Samples was taken by sistematic random sampling based on age and sex. The totals of samples was 430 children. The needs of fissure sealant in the molars were quite high (36,75%, the highest percentage was in the lower first molar (49,64%, followed by the lower second molar (42,92%. In the premolars the needs was low (8,02%, the greatest needs was in the lower second premolar (15,79% followed by upper first premolar (7,50%.

  16. Identifying new sex-linked genes through BAC sequencing in the dioecious plant Silene latifolia

    Czech Academy of Sciences Publication Activity Database

    Blavet, Nicolas; Blavet, Hana; Muyle, A.; Käfer, J.; Cegan, R.; Deschamps, C.; Zemp, N.; Mousset, S.; Aubourg, S.; Bergero, R.; Charlesworth, D.; Hobza, Roman; Widmer, A.; Marais, G.A.B.

    2015-01-01

    Roč. 16, JUL 25 (2015), s. 546 ISSN 1471-2164 R&D Projects: GA ČR GAP501/12/2220 Institutional support: RVO:61389030 Keywords : Sex chromosomes * Sex-linked genes * Plant Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.867, year: 2015

  17. Identifying new sex-linked genes through BAC sequencing in the dioecious plant Silene latifolia

    Czech Academy of Sciences Publication Activity Database

    Blavet, N.; Blavet, Hana; Muyle, A.; Kaefer, J.; Čegan, Radim; Deschamps, C.; Zemp, N.; Mousset, S.; Aubourg, S.; Bergero, R.; Charlesworth, D.; Hobza, Roman; Widmer, A.; Marais, G.A.B.

    2015-01-01

    Roč. 16, JUL 2015 (2015) ISSN 1471-2164 R&D Projects: GA ČR(CZ) GAP501/12/2220 Institutional support: RVO:68081707 Keywords : Y-CHROMOSOME * EVOLUTION * REARRANGEMENTS Subject RIV: BO - Biophysics Impact factor: 3.867, year: 2015

  18. The role of chromosomal rearrangements in the evolution of Silene latifolia sex chromosomes

    Czech Academy of Sciences Publication Activity Database

    Hobza, Roman; Kejnovský, Eduard; Vyskot, Boris; Widmer, A.

    2007-01-01

    Roč. 278, č. 6 (2007), s. 633-638 ISSN 1617-4615 R&D Projects: GA ČR(CZ) GA204/05/2097; GA ČR(CZ) GA521/06/0056 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : chromosomal rearrangements * sex chromosomes * FISH Subject RIV: BO - Biophysics Impact factor: 2.978, year: 2007

  19. Mosaic Origins of a Complex Chimeric Mitochondrial Gene in Silene vulgaris

    Czech Academy of Sciences Publication Activity Database

    Štorchová, Helena; Müller, Karel; Lau, S.; Olson, M. S.

    2012-01-01

    Roč. 7, č. 2 (2012), e30401-- E-ISSN 1932-6203 R&D Projects: GA ČR GA521/09/0261; GA MŠk(CZ) LC06004; GA MŠk ME09035 Institutional research plan: CEZ:AV0Z50380511 Keywords : CYTOPLASMIC MALE-STERILITY * OPEN READING FRAME * COMPLETE NUCLEOTIDE-SEQUENCE Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.730, year: 2012

  20. Accumulation of chloroplast DNA sequences on the Y chromosome of Silene latifolia

    Czech Academy of Sciences Publication Activity Database

    Kejnovský, Eduard; Kubát, Zdeněk; Hobza, Roman; Lengerová, Martina; Sato, S.; Tabata, S.; Fukui, K.; Matsunaga, S.; Vyskot, Boris

    2006-01-01

    Roč. 128, 1-3 (2006), s. 167-175 ISSN 0016-6707 R&D Projects: GA ČR(CZ) GA204/05/2097; GA ČR(CZ) GD204/05/H505; GA AV ČR(CZ) 1QS500040507 Institutional research plan: CEZ:AV0Z50040507 Keywords : accumulation * chloroplast DNA * Y chromosome Subject RIV: BO - Biophysics Impact factor: 1.492, year: 2006

  1. Expression response of duplicated metallothionein 3 gene to copper stress in Silene vulgaris ecotypes

    Czech Academy of Sciences Publication Activity Database

    Nevrtalová, Eva; Baloun, Jiří; Hudzieczek, Vojtěch; Čegan, Radim; Vyskot, Boris; Doležel, Jaroslav; Šafář, Jan; Milde, D.; Hobza, Roman

    2014-01-01

    Roč. 251, č. 6 (2014), s. 1427-1439 ISSN 0033-183X R&D Projects: GA ČR(CZ) GAP501/12/2220; GA ČR(CZ) GBP501/12/G090; GA ČR(CZ) GP13-34962P; GA ČR(CZ) GA522/09/0083 Institutional support: RVO:68081707 Keywords : Copper * Gene duplication * Metallothionein Subject RIV: BO - Biophysics; EF - Botanics (UEB-Q) Impact factor: 2.651, year: 2014

  2. Microbial species delineation using whole genome sequences.

    Science.gov (United States)

    Varghese, Neha J; Mukherjee, Supratim; Ivanova, Natalia; Konstantinidis, Konstantinos T; Mavrommatis, Kostas; Kyrpides, Nikos C; Pati, Amrita

    2015-08-18

    Increased sequencing of microbial genomes has revealed that prevailing prokaryotic species assignments can be inconsistent with whole genome information for a significant number of species. The long-standing need for a systematic and scalable species assignment technique can be met by the genome-wide Average Nucleotide Identity (gANI) metric, which is widely acknowledged as a robust measure of genomic relatedness. In this work, we demonstrate that the combination of gANI and the alignment fraction (AF) between two genomes accurately reflects their genomic relatedness. We introduce an efficient implementation of AF,gANI and discuss its successful application to 86.5M genome pairs between 13,151 prokaryotic genomes assigned to 3032 species. Subsequently, by comparing the genome clusters obtained from complete linkage clustering of these pairs to existing taxonomy, we observed that nearly 18% of all prokaryotic species suffer from anomalies in species definition. Our results can be used to explore central questions such as whether microorganisms form a continuum of genetic diversity or distinct species represented by distinct genetic signatures. We propose that this precise and objective AF,gANI-based species definition: the MiSI (Microbial Species Identifier) method, be used to address previous inconsistencies in species classification and as the primary guide for new taxonomic species assignment, supplemented by the traditional polyphasic approach, as required. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  3. Alien species on the coasts of Turkey

    Directory of Open Access Journals (Sweden)

    M.E. CINAR

    2005-12-01

    Full Text Available The compilation of data on alien species reported from the Turkish coasts yielded a total of 263 species belonging to 11 systematic groups, of which Mollusca had the highest number of species (85 species, followed by Crustacea (51, fishes (43 and phytobenthos (39. The Black Sea is represented by a total of 20 alien species, the Sea of Marmara by 48 species, the Aegean Sea by 98 species and the Levantine Sea by 202 species. The majority of aliens found in the Black Sea and the Sea of Marmara were transported via shipping, whereas the Levantine coast is extensively subjected to Lessepsian migration. Benthic habitats (soft and hard substrata comprise 76% of the total alien species and the pelagic environment is inhabited by thirty-nine species. Almost 50% of aliens collected from the Turkish coasts were found only at 0-10 m depth. Eight species occur at depths deeper than 100 m. The impacts of aliens on the benthic and pelagic ecosystems are presented.

  4. Genomic definition of species. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Crkvenjakov, R.; Drmanac, R.

    1993-03-01

    A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species- and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called species genome. Our proposal for the definition of a biological species is as follows: A species comprises a group of actual and potential biological organisms built according to a unique genome program that is recorded, and at least in part expressed, in the structures of their genomic nucleic acid molecule(s), having intragroup sequence differences which can be fully interconverted in the process of organismal reproduction.

  5. Genomic definition of species. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Crkvenjakov, R.; Dramanac, R.

    1992-06-01

    A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called (species) genome. The definition of species based on chromosomes, genes, or genome common to its member organisms has been implied or mentioned in passing numerous times. Some population biologists think that members of species have similar ``homeostatic genotypes,`` which are to a degree resistant to mutation or environmental change in the production of a basic phenotype.

  6. Sea Cucumber (Holothuroidea Species of Turkey

    Directory of Open Access Journals (Sweden)

    Mehmet AYDIN

    2016-11-01

    Full Text Available There are nearly 1200 sea cucumber species in the world oceans, while only 37 species from Holothuroidea class lives in the Mediterranean Sea. This preliminary study aims identification sea cucumbers species of the Turkish waters. The sea cucumber samples used in this study were obtained from a series of different studies between the years of 2008 and 2014. Identification of the species are mainly based on the morphometric characteristics while some of species are determined from their calcareous spicules. Eight sea species were identified in this research which are; Holothuria tubulosa, Holothuria polii, Holothuria mammata, Holothuria (Platyperona sanctori, Holothuria forskali, Stichopus regalis, Synaptula reciprocans and Stereoderma kirschbergi. There are limited number of studies in the literature focusing on the identification of the sea cucumber species spread in our seas. Therefore, this study is believed to play an important role in guiding future researches.

  7. Fisheries oceanography of northern pelagic fish species

    DEFF Research Database (Denmark)

    Tsoukali, Stavroula

    for marine organisms. One of the impacts will be the time that species start to spawn, and there is already evidence for earlier spawning in some North Sea fish species. A change like that may likely have a chain reaction, affecting larval stages and whether they will live in environments with high food...... of the species they consume now and increased availability of new species. In addition, there will likely be economic impacts on the local fishing communities. How species respond to climate change is a field of research that receives great attention because the responses will affect the management of fisheries......People are familiar with marine fish species and the great variety of different species that are available in the market, such as herring, cod and sole. What may not be well known is that every individual fish goes through a long, risky journey during its life before reaching maturity. Most...

  8. Four new species of Pteromalus Swederus (Hymenoptera: Chalcidoidea: Pteromalidae) and redescriptions of three other species

    NARCIS (Netherlands)

    Gijswijt, M.J.

    1999-01-01

    A key to the European species of the Pteromalus altus group is presented. The relationship between this group and species of the genus Euphorbia (Euphorbiaceae) is confirmed. One new species: P. villosae, associated with Euphorbia villosa Waldst. & Kit.is presented. Two new species of the albipennis

  9. Palpi aplenty: New species in the Chrysotus longipalpus species group (Diptera: Dolichopodidae)

    Science.gov (United States)

    Justin B. Runyon; Renato S. Capellari

    2018-01-01

    Four new Nearctic species belonging to the Chrysotus longipalpus species group are described: Chrysotus keyensis sp. nov. (Florida), Chrysotus mccreadiei sp. nov. (Alabama), Chrysotus mystax sp. nov. (Alabama), and Chrysotus plumarista sp. nov. (Alabama). This brings the number of known species in this group to twelve. A key to species of males of the C. longipalpus...

  10. A globally-distributed alien invasive species poses risks to United States imperiled species.

    Science.gov (United States)

    McClure, Meredith L; Burdett, Christopher L; Farnsworth, Matthew L; Sweeney, Steven J; Miller, Ryan S

    2018-03-28

    In the midst of Earth's sixth mass extinction event, non-native species are a driving factor in many imperiled species' declines. One of the most widespread and destructive alien invasive species in the world, wild pigs (Sus scrofa) threaten native species through predation, habitat destruction, competition, and disease transmission. We show that wild pigs co-occur with up to 87.2% of imperiled species in the contiguous U.S. identified as susceptible to their direct impacts, and we project increases in both the number of species at risk and the geographic extent of risks by 2025. Wild pigs may therefore present a severe threat to U.S. imperiled species, with serious implications for management of at-risk species throughout wild pigs' global distribution. We offer guidance for efficient allocation of research effort and conservation resources across species and regions using a simple approach that can be applied to wild pigs and other alien invasive species globally.

  11. Bacillus cereus and related species.

    Science.gov (United States)

    Drobniewski, F A

    1993-10-01

    Bacillus cereus is a gram-positive aerobic or facultatively anaerobic spore-forming rod. It is a cause of food poisoning, which is frequently associated with the consumption of rice-based dishes. The organism produces an emetic or diarrheal syndrome induced by an emetic toxin and enterotoxin, respectively. Other toxins are produced during growth, including phospholipases, proteases, and hemolysins, one of which, cereolysin, is a thiol-activated hemolysin. These toxins may contribute to the pathogenicity of B. cereus in nongastrointestinal disease. B. cereus isolated from clinical material other than feces or vomitus was commonly dismissed as a contaminant, but increasingly it is being recognized as a species with pathogenic potential. It is now recognized as an infrequent cause of serious nongastrointestinal infection, particularly in drug addicts, the immunosuppressed, neonates, and postsurgical patients, especially when prosthetic implants such as ventricular shunts are inserted. Ocular infections are the commonest types of severe infection, including endophthalmitis, panophthalmitis, and keratitis, usually with the characteristic formation of corneal ring abscesses. Even with prompt surgical and antimicrobial agent treatment, enucleation of the eye and blindness are common sequelae. Septicemia, meningitis, endocarditis, osteomyelitis, and surgical and traumatic wound infections are other manifestations of severe disease. B. cereus produces beta-lactamases, unlike Bacillus anthracis, and so is resistant to beta-lactam antibiotics; it is usually susceptible to treatment with clindamycin, vancomycin, gentamicin, chloramphenicol, and erythromycin. Simultaneous therapy via multiple routes may be required.

  12. Antibiotic resistance in Burkholderia species.

    Science.gov (United States)

    Rhodes, Katherine A; Schweizer, Herbert P

    2016-09-01

    The genus Burkholderia comprises metabolically diverse and adaptable Gram-negative bacteria, which thrive in often adversarial environments. A few members of the genus are prominent opportunistic pathogens. These include Burkholderia mallei and Burkholderia pseudomallei of the B. pseudomallei complex, which cause glanders and melioidosis, respectively. Burkholderia cenocepacia, Burkholderia multivorans, and Burkholderia vietnamiensis belong to the Burkholderia cepacia complex and affect mostly cystic fibrosis patients. Infections caused by these bacteria are difficult to treat because of significant antibiotic resistance. The first line of defense against antimicrobials in Burkholderia species is the outer membrane penetration barrier. Most Burkholderia contain a modified lipopolysaccharide that causes intrinsic polymyxin resistance. Contributing to reduced drug penetration are restrictive porin proteins. Efflux pumps of the resistance nodulation cell division family are major players in Burkholderia multidrug resistance. Third and fourth generation β-lactam antibiotics are seminal for treatment of Burkholderia infections, but therapeutic efficacy is compromised by expression of several β-lactamases and ceftazidime target mutations. Altered DNA gyrase and dihydrofolate reductase targets cause fluoroquinolone and trimethoprim resistance, respectively. Although antibiotic resistance hampers therapy of Burkholderia infections, the characterization of resistance mechanisms lags behind other non-enteric Gram-negative pathogens, especially ESKAPE bacteria such as Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Species longevity in North American fossil mammals.

    Science.gov (United States)

    Prothero, Donald R

    2014-08-01

    Species longevity in the fossil record is related to many paleoecological variables and is important to macroevolutionary studies, yet there are very few reliable data on average species durations in Cenozoic fossil mammals. Many of the online databases (such as the Paleobiology Database) use only genera of North American Cenozoic mammals and there are severe problems because key groups (e.g. camels, oreodonts, pronghorns and proboscideans) have no reliable updated taxonomy, with many invalid genera and species and/or many undescribed genera and species. Most of the published datasets yield species duration estimates of approximately 2.3-4.3 Myr for larger mammals, with small mammals tending to have shorter species durations. My own compilation of all the valid species durations in families with updated taxonomy (39 families, containing 431 genera and 998 species, averaging 2.3 species per genus) yields a mean duration of 3.21 Myr for larger mammals. This breaks down to 4.10-4.39 Myr for artiodactyls, 3.14-3.31 Myr for perissodactyls and 2.63-2.95 Myr for carnivorous mammals (carnivorans plus creodonts). These averages are based on a much larger, more robust dataset than most previous estimates, so they should be more reliable for any studies that need species longevity to be accurately estimated. © 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  14. A Theory of Flagship Species Action

    Directory of Open Access Journals (Sweden)

    Paul Jepson

    2015-01-01

    Full Text Available The flagship species approach is an enduring strategy in conservation. Academic discussion on flagship species has focussed on two dimensions: on what basis should they be selected and how have they been put to use. Here we consider a third dimension, namely the manner in which flagship species act and have the capacity to galvanise and influence conservation outcomes. Drawing on concepts from the social sciences, viz. affordance, framing, and actor-networks; we discuss examples of flagship species to propose a theory of flagship species action. In brief, our theory posits that a flagship species is one with traits that afford the assembly of relatively coherent networks of associations with ideational elements located in pre-existing cultural framings. These associations give rise to opportunities to align with deep cultural frames, contemporary cultural phenomena and political economy such that when a conservation action is introduced, forms of agency cause the species and human publics to change. The species becomes re-framed (or reinvigorated as a cultural asset speaking for a wider nature, publics and political agendas. Further our theory posits that species with traits that enrol in idea networks incorporating human fears, will have limited flagship capacity. This is because the ability of the representations produced to align with frames incorporating collective aspirations is constrained. In terms of applied conservation practice, our theory suggests that: a key criteria for selecting potential flagship species is presence in existing cultural frames, that effective deployment of flagship species requires an understanding of the species′ cultural associations, and a species ability to galvanise action may be limited to certain times and places. Furthermore, once deployed conservation interests will never have full control over the flagship species: it may act in uncertain and unexpected ways.

  15. Competition between species of small mammals

    International Nuclear Information System (INIS)

    Grant, P.R.

    1978-01-01

    Interspecific competition has often been inferred from its results. In evolutionary time it has been responsible for patterns of regularity in the structure of mammalian communities, and in the morphological and ecological characteristics of the constituent species. In contemporary time it gives rise to reciprocal (complementary) numbers and distributions of two or more species. These inferences are strengthened by recent experimental demonstrations of competition between species of North American rodents. Recent observations and experiments are reviewed. The most thoroughly studied competitors are two species of microtine rodents, Microtus pennsylvanicus and Clethrionomys gapperi. Species which compete for space have been studied experimentally more often than have food competitors. Overt aggression is frequently implicated, but its importance in nature in relation to other means of interaction (e.g. through vocal or scent communication) is not known. The definitive study of competition for food between mammal species has yet to be performed

  16. Radiation protection of non-human species

    International Nuclear Information System (INIS)

    Leith, I.S.

    1993-01-01

    The effects of radiation on non-human species, both animals and plants, have long been investigated. In the disposal of radioactive wastes, the protection of non-human species has been investigated. Yet no radiation protection standard for exposure of animals and plants per se has been agreed. The International Commission on Radiological Protection has long taken the view that, if human beings are properly protected from radiation, other species will thereby be protected to the extent necessary for their preservation. However, the International Atomic Energy Agency has found it necessary to investigate the protection of non-human species where radioactivity is released to an environment unpopulated by human beings. It is proposed that the basis of such protection, and the knowledge of radiation effects on non-human species on which it is based, suggest a practical radiation protection standard for non-human species. (1 tab.)

  17. On the Mass Distribution of Animal Species

    Science.gov (United States)

    Redner, Sidney; Clauset, Aaron; Schwab, David

    2009-03-01

    We develop a simple diffusion-reaction model to account for the broad and asymmetric distribution of adult body masses for species within related taxonomic groups. The model assumes three basic evolutionary features that control body mass: (i) a fixed lower limit that is set by metabolic constraints, (ii) a species extinction risk that is a weakly increasing function of body mass, and (iii) cladogenetic diffusion, in which daughter species have a slight tendency toward larger mass. The steady-state solution for the distribution of species masses in this model can be expressed in terms of the Airy function. This solution gives mass distributions that are in good agreement with data on 4002 terrestrial mammal species from the late Quaternary and 8617 extant bird species.

  18. Aging and immortality in unicellular species.

    Science.gov (United States)

    Florea, Michael

    2017-10-01

    It has been historically thought that in conditions that permit growth, most unicellular species do not to age. This was particularly thought to be the case for symmetrically dividing species, as such species lack a clear distinction between the soma and the germline. Despite this, studies of the symmetrically dividing species Escherichia coli and Schizosaccharomyces pombe have recently started to challenge this notion. They indicate that E. coli and S. pombe do age, but only when subjected to environmental stress. If true, this suggests that aging may be widespread among microbial species in general, and that studying aging in microbes may inform other long-standing questions in aging. This review examines the recent evidence for and against replicative aging in symmetrically dividing unicellular organisms, the mechanisms that underlie aging, why aging evolved in these species, and how microbial aging fits into the context of other questions in aging. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Costs Associated with Endangered Species Act Compliance

    Science.gov (United States)

    2013-08-01

    August 2013 2 on economic costs or values related to endangered species costs or values, focuses primarily on Contingent Valuation Method studies...of species preservation (Lew, Layton, and Rowe 2010; Wallmo 2006). Most studies consider public valuation of species preservation, and not costs of...2012, NMFS 2006, U.S. Army Engineer, Mississippi Valley Division 2012, Kozlowski 1993, PFMC 2002) and through development of expenditure categories

  20. The transformer species of the Ukrainian Polissya

    Directory of Open Access Journals (Sweden)

    Protopopova Vira V.

    2015-09-01

    Full Text Available The investigation results of the transformer species participation (Echinocystis lobata (Michx. Torr. & A. Gray, Heracleum sosnowskyi Manden., Impatiens glandulifera Royle, I. parviflora DC., Reynoutria japonica Houtt., Robinia pseudoacacia L. in different plant communities of the Ukrainian Polissya (Forest zone of Ukraine are presented. All the abovementioned species are strong edificators in the region that can significantly change important species composition parameters of communities and character of landscape.

  1. Species - San Diego Co. [ds121

    Data.gov (United States)

    California Natural Resource Agency — This is the Biological Observation Database point layer representing baseline observations of sensitive species (as defined by the MSCP) throughout San Diego County....

  2. Biological species in the viral world.

    Science.gov (United States)

    Bobay, Louis-Marie; Ochman, Howard

    2018-06-05

    Due to their dependence on cellular organisms for metabolism and replication, viruses are typically named and assigned to species according to their genome structure and the original host that they infect. But because viruses often infect multiple hosts and the numbers of distinct lineages within a host can be vast, their delineation into species is often dictated by arbitrary sequence thresholds, which are highly inconsistent across lineages. Here we apply an approach to determine the boundaries of viral species based on the detection of gene flow within populations, thereby defining viral species according to the biological species concept (BSC). Despite the potential for gene transfer between highly divergent genomes, viruses, like the cellular organisms they infect, assort into reproductively isolated groups and can be organized into biological species. This approach revealed that BSC-defined viral species are often congruent with the taxonomic partitioning based on shared gene contents and host tropism, and that bacteriophages can similarly be classified in biological species. These results open the possibility to use a single, universal definition of species that is applicable across cellular and acellular lifeforms.

  3. Use of species-specific PCR for the identification of 10 sea cucumber species

    Science.gov (United States)

    Wen, Jing; Zeng, Ling

    2014-11-01

    We developed a species-specific PCR method to identify species among dehydrated products of 10 sea cucumber species. Ten reverse species-specific primers designed from the 16S rRNA gene, in combination with one forward universal primer, generated PCR fragments of ca. 270 bp length for each species. The specificity of the PCR assay was tested with DNA of samples of 21 sea cucumber species. Amplification was observed in specific species only. The species-specific PCR method we developed was successfully applied to authenticate species of commercial products of dehydrated sea cucumber, and was proven to be a useful, rapid, and low-cost technique to identify the origin of the sea cucumber product.

  4. Relating species abundance distributions to species-area curves in two Mediterranean-type shrublands

    Science.gov (United States)

    Keeley, Jon E.

    2003-01-01

    Based on both theoretical and empirical studies there is evidence that different species abundance distributions underlie different species-area relationships. Here I show that Australian and Californian shrubland communities (at the scale from 1 to 1000 m2) exhibit different species-area relationships and different species abundance patterns. The species-area relationship in Australian heathlands best fits an exponential model and species abundance (based on both density and cover) follows a narrow log normal distribution. In contrast, the species-area relationship in Californian shrublands is best fit with the power model and, although species abundance appears to fit a log normal distribution, the distribution is much broader than in Australian heathlands. I hypothesize that the primary driver of these differences is the abundance of small-stature annual species in California and the lack of annuals in Australian heathlands. Species-area is best fit by an exponential model in Australian heathlands because the bulk of the species are common and thus the species-area curves initially rise rapidly between 1 and 100 m2. Annuals in Californian shrublands generate very broad species abundance distributions with many uncommon or rare species. The power function is a better model in these communities because richness increases slowly from 1 to 100 m2 but more rapidly between 100 and 1000 m2due to the abundance of rare or uncommon species that are more likely to be encountered at coarser spatial scales. The implications of this study are that both the exponential and power function models are legitimate representations of species-area relationships in different plant communities. Also, structural differences in community organization, arising from different species abundance distributions, may lead to different species-area curves, and this may be tied to patterns of life form distribution.

  5. New xenophytes from La Palma (Canary Islands, Spain, with emphasis on naturalized and (potentially invasive species

    Directory of Open Access Journals (Sweden)

    R. Otto

    2016-07-01

    Full Text Available Many years of field work in La Palma (western Canary Islands yielded a number of interesting new records of non-native vascular plants. Amaranthus blitoides, A. deflexus, Aptenia cordifolia, Argemone ochroleuca, Begonia schmidtiana, Capsella rubella, Cardamine hamiltonii, Centratherum punctatum, Cerastium fontanum subsp. vulgare, Chasmanthe floribunda (widely confused with C. aethiopica and Crocosmia xcrocosmiiflora in Macaronesia, Chenopodium probstii, Commelina latifolia var. latifolia, Dichondra micrantha, Dysphania anthelmintica, Epilobium ciliatum, Erigeron sumatrensis, Erodium neuradifolium, Eucalyptus globulus, Euphorbia hypericifolia, E. maculata, Gamochaeta antillana, Geranium pyrenaicum, Hedychium coronarium, Hypochaeris radicata, Kalanchoe daigremontiana, K. delagoensis, K. xhoughtonii, Kickxia commutata subsp. graeca, K. spuria subsp. integrifolia, Lactuca viminea subsp. ramosissima, Landoltia punctata, Malvastrum coromandelianum subsp. capitatospicatum, Oenothera jamesii, Orobanche nana, Oxalis latifolia, Papaver hybridum, P. setigerum, Pilea microphylla, Podranea ricasoliana, Polygonum arenastrum, Portulaca granulatostellulata, P. nicaraguensis, P. nitida, P. papillatostellulata, Rumex crispus subsp. crispus, R. pulcher subsp. pulcher, R. xpratensis, Sechium edule, Sida spinosa var. angustifolia, Silene nocturna, Solanum abutiloides, S. alatum, S. decipiens, Sonchus tenerrimus, Spergularia marina, Stellaria pallida, Tragopogon porrifolius subsp. australis, Tribulus terrestris and Trifolium repens subsp. repens are naturalized or (potentially invasive xenophytes, reported for the first time from either the Canary Islands or from La Palma. 37 additional, presumably ephemeral taxa are reported for the first time from the Canary Islands, whereas 56 ephemeral taxa are new for La Palma..

  6. Two new species of nocturnal bees of the genus Megalopta (Hymenoptera: Halictidae) with keys to species.

    Science.gov (United States)

    Gonzalez, Victor H; Griswold, Terry; Ayala, Ricardo

    2010-03-01

    Megalopta Smith, 1853, is a Neotropical genus of nocturnal or crepuscular bees. Two subgenera are recognized with most of its nearly 30 species placed in the nominate subgenus. Species of Megalopta s. str. are more commonly collected than species of Noctoraptor Engel et al. 1997, all presumably parasites of Megalopta s. str. Two new species of Megalopta are described here: M. (Megalopta) tetewana, n. sp., from Mexico and M. (Noctoraptor) huaoranii, n. sp., from Ecuador. Identification keys to the Central American species of Megalopta s. str. and the species of the parasitic subgenus Noctoraptor are presented.

  7. The species velocity of trees in Alaska

    Science.gov (United States)

    Morrison, B. D.; Napier, J.; de Lafontaine, G.; Heath, K.; Li, B.; Hu, F.; Greenberg, J. A.

    2017-12-01

    Anthropogenic climate change has motivated interest in the paleo record to enhance our knowledge about past vegetation responses to climate change and help understand potential responses in the future. Additionally, polar regions currently experience the most rapid rates of climate change globally, prompting concern over changes in the ecological composition of high latitude ecosystems. Recent analyses have attempted to construct methods to estimate a species' ability to track climate change by computing climate velocity; a measure of the rate of climate displacement across a landscape which may indicate the speed an organism must migrate to keep pace with climate change. However, a challenge to using climate velocity in understanding range shifts is a lack of species-specificity in the velocity calculations: climate velocity does not actually use any species data in its analysis. To solve the shortcomings of climate velocity in estimating species displacement rates, we computed the "species velocity" of white spruce, green and grey alder populations across the state of Alaska from the Last Glacial Maximum (LGM) to today. Species velocity represents the rate and direction a species is required to migrate to keep pace with a changing climate following the LGM. We used a species distribution model to determine past and present white spruce and alder distributions using statistically downscaled climate data at 60m. Species velocity was then derived from the change in species distribution per year by the change in distribution over Alaska (km/yr). High velocities indicate locations where the species environmental envelope is changing drastically and must disperse rapidly to survive climate change. As a result, high velocity regions are more vulnerable to distribution shifts and higher risk of local extinction. Conversely, low species velocities indicate locations where the local climate envelope is shifting relatively slowly, reducing the stress to disperse quickly

  8. Evaluating species richness: biased ecological inference results from spatial heterogeneity in species detection probabilities

    Science.gov (United States)

    McNew, Lance B.; Handel, Colleen M.

    2015-01-01

    Accurate estimates of species richness are necessary to test predictions of ecological theory and evaluate biodiversity for conservation purposes. However, species richness is difficult to measure in the field because some species will almost always be overlooked due to their cryptic nature or the observer's failure to perceive their cues. Common measures of species richness that assume consistent observability across species are inviting because they may require only single counts of species at survey sites. Single-visit estimation methods ignore spatial and temporal variation in species detection probabilities related to survey or site conditions that may confound estimates of species richness. We used simulated and empirical data to evaluate the bias and precision of raw species counts, the limiting forms of jackknife and Chao estimators, and multi-species occupancy models when estimating species richness to evaluate whether the choice of estimator can affect inferences about the relationships between environmental conditions and community size under variable detection processes. Four simulated scenarios with realistic and variable detection processes were considered. Results of simulations indicated that (1) raw species counts were always biased low, (2) single-visit jackknife and Chao estimators were significantly biased regardless of detection process, (3) multispecies occupancy models were more precise and generally less biased than the jackknife and Chao estimators, and (4) spatial heterogeneity resulting from the effects of a site covariate on species detection probabilities had significant impacts on the inferred relationships between species richness and a spatially explicit environmental condition. For a real dataset of bird observations in northwestern Alaska, the four estimation methods produced different estimates of local species richness, which severely affected inferences about the effects of shrubs on local avian richness. Overall, our results

  9. Species-specific associations between overstory and understory tree species in a semideciduous tropical forest

    Directory of Open Access Journals (Sweden)

    Flaviana Maluf Souza

    2015-03-01

    Full Text Available We investigated the occurrence of associations between overstory and understory tree species in a semideciduous tropical forest. We identified and measured all trees of nine canopy species with diameter at breast height ≥4.8 cm in a 10.24 ha plot and recorded all individuals beneath their canopies ("understory individuals" within the same diameter class. The total density of understory individuals did not significantly differ under different overstory species. One overstory species (Ceiba speciosa showed higher understory species richness compared with five other species. There was a strong positive association between three overstory species (Esenbeckia leiocarpa, Savia dictyocarpa, and C. speciosa and the density of seven understory species (Balfourodendron riedelianum, Chrysophyllum gonocarpum, E. leiocarpa, Holocalyx balansae, Machaerium stipitatum, Rhaminidium elaeocarpum, and S. dictyocarpa. These results probably reflect the outcome of a complex set of interactions including facilitation and competition, and further studies are necessary to better understand the magnitude and type of the effects of individual overstory species on understory species. The occurrence of species-specific associations shown here reinforces the importance of non-random processes in structuring plant communities and suggest that the influence of overstory species on understory species in high-diversity forests may be more significant than previously thought.

  10. New Species of Orchids from Vietnam

    Directory of Open Access Journals (Sweden)

    Leonid V. Averyanov

    2007-12-01

    Full Text Available Identification of herbarium specimens collected in course of field exploration works in Vietnam during 2005-2007 revealed ten species of orchids new for science. Illustrated descriptions are provided for each discovered species, which are named as Anoectochilus papillosus, Arundina caespitosa, Bulbophyllum paraemarginatum, B. sinhoënse, Cheirostylis foliosa, Goodyera rhombodoides, Liparis rivularis, Oberonia multidentata, O. trichophora and Sunipia nigricans.

  11. Xanthomendoza borealis - a bipolar lichen species

    DEFF Research Database (Denmark)

    LIndblom, Louise; Søchting, Ulrik

    It has been uncertain whether the two xanthorioid taxa known as Xanthoria mawsonii and Xanthomen-doza borealis truly are distinct species or if they should best be treated as one species. They are morphologically very similar, but inhabit two disjunct geographical areas, that is, circumpolar on t...

  12. Rapid molecular technique to distinguish Fusarium species

    CSIR Research Space (South Africa)

    Lodolo, EJ

    1993-03-01

    Full Text Available The nuclear DNA (nDNA) of different isolates of three closely related, toxin-producing Fusarium species, F. moniliforme, F. nygamai and F. napiforme, was compared to ascertain the sensitivity of a molecular method to distinguish these three species...

  13. Antibiotic susceptibilities of Salmonella species prevalent among ...

    African Journals Online (AJOL)

    This study was conducted to assess the prevalence of Salmonella species among children having diarrhea in Katsina State, Nigeria. A total of 220 diarrhea stool samples of children aged five years and below (0-5 years) were collected and screened for Salmonella species using culture technique. Presumptively positive ...

  14. In vitro propagation of Fraxinus species

    Science.gov (United States)

    J.W. Van Sambeek; J.E. Preece

    2007-01-01

    The genus Fraxinus, a member of the Oleaceae family, includes over 65 ash species native to the temperate regions of the northern hemisphere (Miller, 1955). Several of the ash species are important forest trees noted for their tough, highly resistant to shock, straight grained wood as well as being excellent shade trees for parks and residential...

  15. Molecular characterization of thermophilic Campylobacter species ...

    African Journals Online (AJOL)

    We identified two species of thermophilic Campylobacter in companion dogs in Jos. Majority of C. jejuni were isolated from mucoid faeces while mixed infections of the two species were more common among diarrhoeic dogs. Pet owners should observe strict hand hygiene especially after handling dogs or their faeces to ...

  16. Two New American Species of Hordeum (Poaceae)

    DEFF Research Database (Denmark)

    Bothmer, Roland Von; Jacobsen, Niels; Bagger Jørgensen, Rikke

    1985-01-01

    Two new species of Hordeum are described, viz. the diploid H. erectifolium, native to Argentina, and H. guatemalense, native to Guatemala.......Two new species of Hordeum are described, viz. the diploid H. erectifolium, native to Argentina, and H. guatemalense, native to Guatemala....

  17. New and noteworthy Malesian species of Loranthaceae

    NARCIS (Netherlands)

    Barlow, Bryan A.

    1995-01-01

    Ten new or noteworthy Malesian species of Loranthaceae are discussed. The known area of the relictual Cecarria obtusifolia (Merrill) Barlow is increased to include Flores and Timor. Dendrophthoe curvata (Blume) Miquel is accepted as a distinct species. The status of Dendrophthoe falcata (L. f.)

  18. On two new species of Cercopithecus

    NARCIS (Netherlands)

    Jentink, F.A.

    1886-01-01

    In 1877 our Museum received a Cercopithecus died in the Zoological Garden at Rotterdam. Professor Schlegel thought it to be a new species and called it Cercopithecus signatus, but he never described it. As it seems to me to be a very good species I describe it under the name given by Schlegel. It

  19. Species diversity of Trichoderma in Poland

    Science.gov (United States)

    Fifteen species of Trichoderma were identified from among 118 strains originating from different regions and ecological niches in Poland. This low number indicates low species diversity of Trichoderma in this Central European region. Using the ITS1-ITS2 regions, 64 strains were positively identified...

  20. Prevalence of Cryptosporidium species and Giardia intestinalis ...

    African Journals Online (AJOL)

    Cryptosporidium species and Giardia intestinalis cause diarrheal infections in humans and other vertebrate animals globally and are considered to be of great public health importance. The study was conducted to determine the prevalence Cryptosporidium species and G. intestinalis infections among patients attending ...

  1. New species of haematozoa in Phalacrocoracidae and ...

    African Journals Online (AJOL)

    New species of haematozoa, namely Leucocytozoon ugwidi sp. nov. from the Cape Cormorant Phalacrocorax capensis and Haemoproteus skuae sp. nov. from the Subantarctic Skua Catharacta antarctica, are described. These are the first species to be recorded from the families Phalacrocoracidae and Stercorariidae, ...

  2. Metabolite production by differnt Ulocladium species

    DEFF Research Database (Denmark)

    Andersen, Birgitte; Hollensted, Morten

    2008-01-01

    Ulocladium, which is phylogenetically related to Alternaria, contains species that are food spoilers and plant pathogens, but also species that have potential as enzyme producers and bio-control agents. Ulocladium spp. are often found on dead vegetation, in soil, air and dust, but also on food...

  3. Species hybridization in the genus Pinus

    Science.gov (United States)

    Peter W. Garrett

    1979-01-01

    Results of a breeding program in which a large number of pine species were tested indicate that a number of species and hybrids may be useful in the northeastern United States. Austrian black pine x Japanese black pine and hybrids containing Japanese red pine all had good growth rates. While none of the soft pines grew faster than eastern white pine, a number of...

  4. Toward reassessing data-deficient species.

    Science.gov (United States)

    Bland, Lucie M; Bielby, Jon; Kearney, Stephen; Orme, C David L; Watson, James E M; Collen, Ben

    2017-06-01

    One in 6 species (13,465 species) on the International Union for Conservation of Nature (IUCN) Red List is classified as data deficient due to lack of information on their taxonomy, population status, or impact of threats. Despite the chance that many are at high risk of extinction, data-deficient species are typically excluded from global and local conservation priorities, as well as funding schemes. The number of data-deficient species will greatly increase as the IUCN Red List becomes more inclusive of poorly known and speciose groups. A strategic approach is urgently needed to enhance the conservation value of data-deficient assessments. To develop this, we reviewed 2879 data-deficient assessments in 6 animal groups and identified 8 main justifications for assigning data-deficient status (type series, few records, old records, uncertain provenance, uncertain population status or distribution, uncertain threats, taxonomic uncertainty, and new species). Assigning a consistent set of justification tags (i.e., consistent assignment to assessment justifications) to species classified as data deficient is a simple way to achieve more strategic assessments. Such tags would clarify the causes of data deficiency; facilitate the prediction of extinction risk; facilitate comparisons of data deficiency among taxonomic groups; and help prioritize species for reassessment. With renewed efforts, it could be straightforward to prevent thousands of data-deficient species slipping unnoticed toward extinction. © 2016 Society for Conservation Biology.

  5. Preliminary observations on the species composition and ...

    African Journals Online (AJOL)

    Majority of the mushrooms appear during the rain season and are equally available during the short and long rains. This suggests that most species will grow well throughout the year whenever moisture level in the substrate is adequate irrespective of the season. Some of the species especially the Polypores (Ganoderma ...

  6. Taxonomy of Penicillium citrinum and related species

    NARCIS (Netherlands)

    Houbraken, J.; Frisvad, J.C.; Samson, R.A.

    2010-01-01

    Penicillium citrinum and related species have been examined using a combination of partial beta-tubulin, calmodulin and ITS sequence data, extrolite patterns and phenotypic characters. It is concluded that seven species belong to the series Citrina. Penicillium sizovae and Penicillium steckii are

  7. Some new or noteworthy species of Mortierella

    NARCIS (Netherlands)

    Gams, W.

    1976-01-01

    Twenty-two species of Mortierella are described and distributed over the sections defined by Gams (1970) which include the following new species: Section Pusilla: M. roseo-nana; Section Alpina: M. globalpina and M. polygonia Section Simplex: M. amoeboidea; Section Hygrophila : M. elongatula, M.

  8. DNA species surveillance: Monitoring bushmeat poaching and ...

    African Journals Online (AJOL)

    DNA species identification has applications in such areas as forensic science, systematics, conservation genetics and agriculture. One key anthropogenic activity threatening large wildlife fauna is illegal exploitation. In Kenya, species identification of raw and processed meat products remains a constraint to effective ...

  9. Distribution of crayfish species in Hungarian waters

    NARCIS (Netherlands)

    Mercédesz, Ludányi; Peeters, E.T.H.M.; Kiss, B.; Roessink, I.

    2016-01-01

    Three native crayfish species, i.e.~Astacus astacus, Astacus leptodactylus and Austropotamobius torrentium, occur in Hungary. Lately, however, non-indigenous crustaceans have also invaded the country Their most recent distribution and impact on the occurrences of the native species is not clear.

  10. Grain Unloading Of Arsenic Species In Rice

    Science.gov (United States)

    Rice (Oryza sativa) is the staple food for over half the world's population yet may represent a significant dietary source of inorganic arsenic (As), a nonthreshold, class 1 human carcinogen. Rice grain As is dominated by the inorganic species, and the organic species dim...

  11. SERI Aquatic Species Program: 1983 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    1984-03-01

    During 1983 research was carried out under three tasks: biological, engineering, and analysis. Biological research was aimed at screening for promising species of microalgae, macroalgae, and emergent plants that could be cultivated for energy products. Promising species were studied further to improve yields.

  12. ENDANGERED SPECIES SENSITIVITY AND ECOLOGICAL RISK ASSESSMENT

    Science.gov (United States)

    he U.S. Environmental Protection Agency (EPA), U.S. Fish & Wildlife Service, and National Marine Fisheries Service share a common responsibility for the protection of our nation's aquatic species under the Endangered Species Act (ESA) of 1973. The EPA, under the Federal Insectici...

  13. antimicrobial susceptibility pattern of Salmonella species

    African Journals Online (AJOL)

    user

    ABSTRACT. Treatment of enteric fever is increasingly becoming very challenging due to the increasing wave of antibiotic resistance. This study is a review of the contemporary antimicrobial susceptibility pattern of. Salmonella species. The antimicrobial susceptibility pattern of Salmonella species to a wide range of.

  14. Endangered Species (Plants). LC Science Tracer Bullet.

    Science.gov (United States)

    Niskern, Diana, Comp.

    This guide is intended for those who wish to study the literature dealing with various aspects of endangered plant species. This document includes the following sections, some of which are bibliographies: (1) "Introductions to the Topic"; (2) "Subject Headings" (for endangered species of plants used by the Library of Congress); (3) "General…

  15. Endangered Species: Real Life in Two Dimensions

    Science.gov (United States)

    Henderson, Lynette K.

    2012-01-01

    The focus of "Endangered Species: Real Life in Two Dimensions" is to create awareness about a critical environmental issue. There is a special urgency to this project because large numbers of animal species are currently endangered or on the brink of extinction. In addition to being enlightened about this important topic through research, students…

  16. Multiple bacterial species reside in chronic wounds

    DEFF Research Database (Denmark)

    Gjødsbøl, Kristine; Christensen, Jens Jørgen; Karlsmark, Tonny

    2006-01-01

    species present were identified. More than one bacterial species were detected in all the ulcers. The most common bacteria found were Staphylococcus aureus (found in 93.5% of the ulcers), Enterococcus faecalis (71.7%), Pseudomonas aeruginosa (52.2%), coagulase-negative staphylococci (45.7%), Proteus...

  17. Multiplexed microsatellite markers for seven Metarhizium species

    Science.gov (United States)

    Cross-species transferability of 41 previously published simple sequence repeat (SSR) markers was assessed for 11 species of the entomopathogenic fungus Metarhizium. A collection of 65 Metarhizium isolates including all 54 used in a recent phylogenetic revision of the genus were characterized. Betwe...

  18. The Invasive Plant Species Education Guide

    Science.gov (United States)

    Mason, Kevin; James, Krista; Carlson, Kitrina; D'Angelo, Jean

    2010-01-01

    To help high school students gain a solid understanding of invasive plant species, university faculty and students from the University of Wisconsin-Stout (UW-Stout) and a local high school teacher worked together to develop the Invasive Plant Species (IPS) Education Guide. The IPS Education Guide includes nine lessons that give students an…

  19. The Drosophila bipectinata species complex: phylogenetic ...

    Indian Academy of Sciences (India)

    Navya

    *For Correspondence. e-mail: bashisthsingh2004@rediffmail.com, ... A species complex constitutes groups of closely related species which have diverged ..... there is a strong reproductive isolation too (See review by Singh and Banerjee 2016) .... figure both the loops touch the chromocenter and in our microphotograph ...

  20. CONSERVATION PROGRAMS THAT PROMOTE INVASIVE SPECIES

    Science.gov (United States)

    Invasive plant species are degrading the structure and function of ecosystems throughout the world. Although most state and federal conservation agencies in the U.S. attempt to reduce the impact of invasive species, some agency activities can contribute to the spread of invasive...

  1. Invasive plant species in hardwood tree plantations

    Science.gov (United States)

    Rochelle R. Beasley; Paula M. Pijut

    2010-01-01

    Invasive plants are species that can grow and spread aggressively, mature quickly, and invade an ecosystem causing economic and environmental damage. Invasive plants usually invade disturbed areas, but can also colonize small areas quickly, and may spread and dominate large areas in a few short years. Invasive plant species displace native or desirable forest...

  2. New species of Maerua (Capparaceae) from Angola

    NARCIS (Netherlands)

    Abreu, J.A.; Martins, E.S.; Catarino, L.

    2014-01-01

    Genus Maerua has around 60 species represented on the African continent, of which three have been reported for Angola. Two new species of Maerua (Capparaceae) from Angola are here described. Both are closely similar to M. juncea subsp. juncea, being distinguished by floral traits such as the

  3. 76 FR 30955 - Invasive Species Advisory Committee

    Science.gov (United States)

    2011-05-27

    ... Commerce. The duty of the Council is to provide national leadership regarding invasive species issues... broad array of issues related to preventing the introduction of invasive species and providing for their... with Western-based scientists and practitioners on problems and potential solutions, as well as...

  4. Fatal attraction: rare species in the spotlight.

    Science.gov (United States)

    Angulo, Elena; Deves, Anne-Laure; Saint Jalmes, Michel; Courchamp, Franck

    2009-04-07

    The exploitation of rare and endangered species can end in the species's extinction because the increased value people associate with rarity increases the economic incentive to exploit the last individuals, creating a positive feedback loop. This recently proposed concept, called the anthropogenic Allee effect (AAE), relies on the assumption that people do value rarity, but this remains to be established. Moreover, it also remains to be determined whether attraction to rarity is a trait confined to a minority of hobbyists (e.g. wildlife collectors, exotic pet owners) or characteristic of the general public. We estimated how much the general public valued rare species compared with common ones, using five different metrics related to personal investment: time spent, physical effort, unpleasantness, economic investment and risk. We surveyed the visitors of a zoo. To see the rare species, the visitors to the zoo invested more time in searching and contemplation, they were ready to expend more physical effort, they tolerated more unpleasant conditions, they were willing to pay more and, finally, they risked more to obtain (steal) a rare species. Our results provide substantial evidence of how the general public places more value on rare species, compared with common species. This confirms the AAE as an actual process, which in addition concerns a large part of the population. This has important consequences for the conservation of species that are rare now, or that could become so in the future.

  5. Characterization of Aspergillus species associated with ...

    African Journals Online (AJOL)

    About 82 triphala powder samples were analyzed for the association of different fungi. Results reveal the predominance of Aspergillus as the major genera with six predominant species namely, A. niger, A. flavus, A. fumigatus, A. terreus, A. nidulans and A. amstelodami. Therefore, these six isolated Aspergillus species were ...

  6. Novel Pestivirus Species in Pigs, Austria, 2015.

    Science.gov (United States)

    Lamp, Benjamin; Schwarz, Lukas; Högler, Sandra; Riedel, Christiane; Sinn, Leonie; Rebel-Bauder, Barbara; Weissenböck, Herbert; Ladinig, Andrea; Rümenapf, Till

    2017-07-01

    A novel pestivirus species was discovered in a piglet-producing farm in Austria during virologic examinations of congenital tremor cases. The emergence of this novel pestivirus species, provisionally termed Linda virus, in domestic pigs may have implications for classical swine fever virus surveillance and porcine health management.

  7. Emergent neutrality drives phytoplankton species coexistence

    Science.gov (United States)

    Segura, Angel M.; Calliari, Danilo; Kruk, Carla; Conde, Daniel; Bonilla, Sylvia; Fort, Hugo

    2011-01-01

    The mechanisms that drive species coexistence and community dynamics have long puzzled ecologists. Here, we explain species coexistence, size structure and diversity patterns in a phytoplankton community using a combination of four fundamental factors: organism traits, size-based constraints, hydrology and species competition. Using a ‘microscopic’ Lotka–Volterra competition (MLVC) model (i.e. with explicit recipes to compute its parameters), we provide a mechanistic explanation of species coexistence along a niche axis (i.e. organismic volume). We based our model on empirically measured quantities, minimal ecological assumptions and stochastic processes. In nature, we found aggregated patterns of species biovolume (i.e. clumps) along the volume axis and a peak in species richness. Both patterns were reproduced by the MLVC model. Observed clumps corresponded to niche zones (volumes) where species fitness was highest, or where fitness was equal among competing species. The latter implies the action of equalizing processes, which would suggest emergent neutrality as a plausible mechanism to explain community patterns. PMID:21177680

  8. Finessing atlas data for species distribution models

    NARCIS (Netherlands)

    Niamir, A.; Skidmore, A.K.; Toxopeus, A.G.; Munoz, A.R.; Real, R.

    2011-01-01

    Aim The spatial resolution of species atlases and therefore resulting model predictions are often too coarse for local applications. Collecting distribution data at a finer resolution for large numbers of species requires a comprehensive sampling effort, making it impractical and expensive. This

  9. 77 FR 70456 - Receipt of Applications for Endangered Species Permits

    Science.gov (United States)

    2012-11-26

    ...: TE-13844A Applicant: Aquatic Resources Management, Lexington, Kentucky. Applicant requests amendment... fish species, twelve (12) fresh-water mussel species, one (1) snake species, one (1) insect species and...

  10. ALIEN SPECIES: THEIR ROLE IN AMPHIBIAN POPULATION DECLINES AND RESTORATION

    Science.gov (United States)

    Alien species (also referred to as exotic, invasive, introduced, or normative species) have been implicated as causal agents in population declines of many amphibian species. Herein, we evaluate the relative contributions of alien species and other factors in adversely affecting ...

  11. Biodiversity hotspots house most undiscovered plant species.

    Science.gov (United States)

    Joppa, Lucas N; Roberts, David L; Myers, Norman; Pimm, Stuart L

    2011-08-09

    For most organisms, the number of described species considerably underestimates how many exist. This is itself a problem and causes secondary complications given present high rates of species extinction. Known numbers of flowering plants form the basis of biodiversity "hotspots"--places where high levels of endemism and habitat loss coincide to produce high extinction rates. How different would conservation priorities be if the catalog were complete? Approximately 15% more species of flowering plant are likely still undiscovered. They are almost certainly rare, and depending on where they live, suffer high risks of extinction from habitat loss and global climate disruption. By using a model that incorporates taxonomic effort over time, regions predicted to contain large numbers of undiscovered species are already conservation priorities. Our results leave global conservation priorities more or less intact, but suggest considerably higher levels of species imperilment than previously acknowledged.

  12. New species in Aspergillus section Terrei

    DEFF Research Database (Denmark)

    Samson, R. A.; Peterson, S. W.; Frisvad, Jens Christian

    2011-01-01

    . clade including the type isolate of A. niveus (CBS 115.27) constitutes a lineage closely related to A. carneus. Fennellia nivea, the hypothesized teleomorph is not related to this clade. Aspergillus allahabadii, A. niveus var. indicus, and two species originally placed in section Versicolores, A......Section Terrei of Aspergillus was studied using a polyphasic approach including sequence analysis of parts of the beta-tubulin and calmodulin genes and the ITS region, macro- and micromorphological analyses and examination of extrolite profiles to describe three new species in this section. Based....... floccosus, A. terreus var. africanus, A. terreus var. aureus, while Aspergillus hortai is recognised at species level. Aspergillus terreus NRRL 4017 is described as the new species A. pseudoterreus. Also included in section Terrei are some species formerly placed in sections Flavipedes and Versicolores. A...

  13. Actinomyces Species Isolated from Breast Infections

    Science.gov (United States)

    Loh, S. F.; Morris, T.; Hughes, H.; Dixon, J. M.

    2015-01-01

    Actinomycosis is a chronic infection caused by Actinomyces species characterized by abscess formation, tissue fibrosis, and draining sinuses. The spectrum of infections caused by Actinomyces species ranges from classical invasive actinomycosis to a less invasive form of superficial skin and soft tissue infection. We present a review detailing all Actinomyces species isolated from breast infections in NHS Lothian between 2005 and 2013, Actinomyces species isolated from breast infections referred to the United Kingdom Anaerobe Reference Unit between 1988 and 2014, and cases describing Actinomyces breast infections published in the medical literature since 1994. Actinomyces species are fastidious organisms which can be difficult to identify and are likely to be underascertained as a cause of breast infections. Due to improved diagnostic methods, they are increasingly associated with chronic, recurrent breast infections and may play a more significant role in these infections than has previously been appreciated. PMID:26224846

  14. Region effects influence local tree species diversity.

    Science.gov (United States)

    Ricklefs, Robert E; He, Fangliang

    2016-01-19

    Global patterns of biodiversity reflect both regional and local processes, but the relative importance of local ecological limits to species coexistence, as influenced by the physical environment, in contrast to regional processes including species production, dispersal, and extinction, is poorly understood. Failure to distinguish regional influences from local effects has been due, in part, to sampling limitations at small scales, environmental heterogeneity within local or regional samples, and incomplete geographic sampling of species. Here, we use a global dataset comprising 47 forest plots to demonstrate significant region effects on diversity, beyond the influence of local climate, which together explain more than 92% of the global variation in local forest tree species richness. Significant region effects imply that large-scale processes shaping the regional diversity of forest trees exert influence down to the local scale, where they interact with local processes to determine the number of coexisting species.

  15. The Porphyra species of Helgoland (Bangiales, Rhodophyta)

    Science.gov (United States)

    Kornmann, P.; Sahling, P.-H.

    1991-03-01

    This revision of seven Porphyra species of Helgoland was based on a study of the structure of their fertile thalli and the behaviour of their spores. Regarding the reproductive organization the species may be arranged in two groups. P. leucosticta and P. purpureo-violacea are obligate monoecious species. Asexual thalli have never been observed in the field. The other five species are generally dioecious. Isomorphic sexual thalli and asexually propagating ones are mixed in uniform populations. Carpospores originating from sexual fusion develop into the diploid Conchocelis phase. Sporangia of asexual plants, though homologous in formation, produce spores of different kinds: aplanospores that give rise to the vegetative thallus directly (in P. umbilicalis, P. insolita n. sp. and P. ochotensis) and spores that develop into haploid Conchocelis (in P. laciniata and in P. linearis). P. laciniata — formerly considered synonymous with P. purpurea — is an independent species.

  16. Effects of species' characteristics on nongovernmental organizations' attitudes toward species conservation policy

    NARCIS (Netherlands)

    Knegtering, E; Hendrickx, L.C W P; van der Windt, H.J.; Schoot Uiterkamp, A.J.M.

    The authors examined the willingness of nongovernmental organizations (NGOs) to support public species conservation measures as a function of species characteristics, NGOs' interests, and interests harmed by the measures. In an experiment, 39 policy makers from nature conservation, mobility and

  17. ConSpeciFix: Classifying prokaryotic species based on gene flow.

    Science.gov (United States)

    Bobay, Louis-Marie; Ellis, Brian Shin-Hua; Ochman, Howard

    2018-05-16

    Classification of prokaryotic species is usually based on sequence similarity thresholds, which are easy to apply but lack a biologically-relevant foundation. Here, we present ConSpeciFix, a program that classifies prokaryotes into species using criteria set forth by the Biological Species Concept, thereby unifying species definition in all domains of life. ConSpeciFix's webserver is freely available at www.conspecifix.com. The local version of the program can be freely downloaded from https://github.com/Bobay-Ochman/ConSpeciFix. ConSpeciFix is written in Python 2.7 and requires the following dependencies: Usearch, MCL, MAFFT and RAxML. ljbobay@uncg.edu.

  18. Genetic sorting of subordinate species in grassland modulated by intraspecific variation in dominant species.

    Directory of Open Access Journals (Sweden)

    Danny J Gustafson

    Full Text Available Genetic variation in a single species can have predictable and heritable effects on associated communities and ecosystem processes, however little is known about how genetic variation of a dominant species affects plant community assembly. We characterized the genetic structure of a dominant grass (Sorghastrum nutans and two subordinate species (Chamaecrista fasciculata, Silphium integrifolium, during the third growing season in grassland communities established with genetically distinct (cultivated varieties or local ecotypes seed sources of the dominant grasses. There were genetic differences between subordinate species growing in the cultivar versus local ecotype communities, indicating that intraspecific genetic variation in the dominant grasses affected the genetic composition of subordinate species during community assembly. A positive association between genetic diversity of S. nutans, C. fasciculata, and S. integrifolium and species diversity established the role of an intraspecific biotic filter during community assembly. Our results show that intraspecific variation in dominant species can significantly modulate the genetic composition of subordinate species.

  19. New species of Moenkhausia Eigenmann, 1903 (Characiformes: Characidae with comments on the Moenkhausia oligolepis species complex

    Directory of Open Access Journals (Sweden)

    Ricardo C. Benine

    Full Text Available A new species of Moenkhausia is described from tributaries of the rio Paraguay, Brazil. The new species is diagnosed from congeners by characters related to body coloration, the number of lateral line scales, the degree of poring of the lateral line, and number of scales rows above and below the lateral line. Molecular analyses using partial sequences of the mitochondrial gene Cytochrome Oxidase I from specimens of the new species and specimens belonging to morphologically similar species demonstrated that the new species is easily differentiated by their high genetic distance and by their position in the phylogenetic hypothesis obtained through the Maximum Parsimony methodology. The analyses of three samples of M. oligolepis also revealed that they have high genetic distances and belong to different monophyletic groups suggesting that this species corresponds to a species complex rather than a single species.

  20. 75 FR 38069 - Injurious Wildlife Species; Listing the Boa Constrictor, Four Python Species, and Four Anaconda...

    Science.gov (United States)

    2010-07-01

    ... Python Species, and Four Anaconda Species as Injurious Reptiles AGENCY: Fish and Wildlife Service... regulations to add Indian python (Python molurus, including Burmese python Python molurus bivittatus), reticulated python (Broghammerus reticulatus or Python reticulatus), Northern African python (Python sebae...

  1. Spatial Complementarity and the Coexistence of Species

    Science.gov (United States)

    Velázquez, Jorge; Garrahan, Juan P.; Eichhorn, Markus P.

    2014-01-01

    Coexistence of apparently similar species remains an enduring paradox in ecology. Spatial structure has been predicted to enable coexistence even when population-level models predict competitive exclusion if it causes each species to limit its own population more than that of its competitor. Nevertheless, existing hypotheses conflict with regard to whether clustering favours or precludes coexistence. The spatial segregation hypothesis predicts that in clustered populations the frequency of intra-specific interactions will be increased, causing each species to be self-limiting. Alternatively, individuals of the same species might compete over greater distances, known as heteromyopia, breaking down clusters and opening space for a second species to invade. In this study we create an individual-based model in homogeneous two-dimensional space for two putative sessile species differing only in their demographic rates and the range and strength of their competitive interactions. We fully characterise the parameter space within which coexistence occurs beyond population-level predictions, thereby revealing a region of coexistence generated by a previously-unrecognised process which we term the triadic mechanism. Here coexistence occurs due to the ability of a second generation of offspring of the rarer species to escape competition from their ancestors. We diagnose the conditions under which each of three spatial coexistence mechanisms operates and their characteristic spatial signatures. Deriving insights from a novel metric — ecological pressure — we demonstrate that coexistence is not solely determined by features of the numerically-dominant species. This results in a common framework for predicting, given any pair of species and knowledge of the relevant parameters, whether they will coexist, the mechanism by which they will do so, and the resultant spatial pattern of the community. Spatial coexistence arises from complementary combinations of traits in each

  2. Neosilba (Tephritoidea: Lonchaeidae) species reared from coffee in Brazil, with description of a new species

    Energy Technology Data Exchange (ETDEWEB)

    Striki, Pedro Carlos; Prado, Angelo Pires do, E-mail: apprado@unicamp.b [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Biologia. Dept. de Parasitologia

    2006-07-01

    Neosilba species are believed to be secondary invaders of fruit, so, little attention has been paid to its presence in coffee fruits. In this article we present a key to Neosilba species present in coffee fruits and describe a new species that is considered a primary invader. We hope this will help researchers working with coffee fruits to better quantify the economic importance of Neosilba species associated with coffee fruits. (author)

  3. Neosilba (Tephritoidea: Lonchaeidae) species reared from coffee in Brazil, with description of a new species

    International Nuclear Information System (INIS)

    Striki, Pedro Carlos; Prado, Angelo Pires do

    2006-01-01

    Neosilba species are believed to be secondary invaders of fruit, so, little attention has been paid to its presence in coffee fruits. In this article we present a key to Neosilba species present in coffee fruits and describe a new species that is considered a primary invader. We hope this will help researchers working with coffee fruits to better quantify the economic importance of Neosilba species associated with coffee fruits. (author)

  4. Two new species of nocturnal bees of the genus Megalopta (Hymenoptera: Halictidae) with keys to species

    OpenAIRE

    Gonzalez, Victor H; Griswold, Terry; Ayala, Ricardo

    2010-01-01

    Megalopta Smith, 1853, is a Neotropical genus of nocturnal or crepuscular bees. Two subgenera are recognized with most of its nearly 30 species placed in the nominate subgenus. Species of Megalopta s. str. are more commonly collected than species of Noctoraptor Engel et al. 1997, all presumably parasites of Megalopta s. str. Two new species of Megalopta are described here: M. (Megalopta) tetewana, n. sp., from Mexico and M. (Noctoraptor) huaoranii, n. sp., from Ecuador. Identification keys to...

  5. Dna c-values of 20 invasive alien species and 3 native species in south china

    OpenAIRE

    Gong Ni; Wang Yu-Tao; Björn Lars Olof; Li Shao-Shan

    2014-01-01

    Cultivated fields and forests in South China are experiencing serious damage due to invasive alien plants. We investigated the relation between DNA C-values and invasiveness. The DNA C-values of 23 species ranged from 0.39 pg to 3.37 pg. Herbs, perennials and native species had higher mean DNA C-values than shrubs, annuals and invasive alien species. DNA C-values decreased with increasing invasiveness. Paederia scandens, a harmful native species, has the lo...

  6. Invading species in the Eel River, California: Successes, failures, and relationships with resident species

    Science.gov (United States)

    Brown, L.R.; Moyle, P.B.

    1997-01-01

    We examined invasions of non-native fishes into the Eel River, California. At least 16 species of fish have been introduced into the drainage which originally supported 12-14 fish species. Our study was prompted by the unauthorized introduction in 1979 of Sacramento squawfish, Ptychocheilus grandis, a large predatory cyprinid. From 1986 to 1990, we conducted growth and diet studies of squaw fish, conducted intensive surveys of the distribution and habitat associations of both native and introduced species, and examined the nature of species-habitat and interspecies relationships. We found no evidence for increased growth or expanded feeding habits, compared to native populations, of Sacramento squawfish as they invaded the Eel River drainage. Ten of the introduced species were well established, with four species limited to a reservoir and six species established in streams. The success or failure of introductions of stream species appeared to be a function of the ability of a species to survive the fluctuating, highly seasonal, flow regime. The present mixture of native and exotic species has not formed stable fish assemblages but it seems likely that four habitat-associated assemblages will develop. The overall effect of the successful species introductions has been to assemble a group of species, with some exceptions, that are native to and occur together in many California streams. The assemblages now forming are similar to those found in other California streams. The assemblage characterized by squawfish and suckers is likely to be resistant to invasion, in the absence of human caused habitat modifications.

  7. Rare species contribute disproportionately to the functional structure of species assemblages.

    Science.gov (United States)

    Leitão, Rafael P; Zuanon, Jansen; Villéger, Sébastien; Williams, Stephen E; Baraloto, Christopher; Fortunel, Claire; Mendonça, Fernando P; Mouillot, David

    2016-04-13

    There is broad consensus that the diversity of functional traits within species assemblages drives several ecological processes. It is also widely recognized that rare species are the first to become extinct following human-induced disturbances. Surprisingly, however, the functional importance of rare species is still poorly understood, particularly in tropical species-rich assemblages where the majority of species are rare, and the rate of species extinction can be high. Here, we investigated the consequences of local and regional extinctions on the functional structure of species assemblages. We used three extensive datasets (stream fish from the Brazilian Amazon, rainforest trees from French Guiana, and birds from the Australian Wet Tropics) and built an integrative measure of species rarity versus commonness, combining local abundance, geographical range, and habitat breadth. Using different scenarios of species loss, we found a disproportionate impact of rare species extinction for the three groups, with significant reductions in levels of functional richness, specialization, and originality of assemblages, which may severely undermine the integrity of ecological processes. The whole breadth of functional abilities within species assemblages, which is disproportionately supported by rare species, is certainly critical in maintaining ecosystems particularly under the ongoing rapid environmental transitions. © 2016 The Author(s).

  8. Protectiveness of Species Sensitivity Distribution Hazard Concentrations for Acute Toxicity Used in Endangered Species Risk Assessment

    Science.gov (United States)

    A primary objective of threatened and endangered species conservation is to ensure that chemical contaminants and other stressors do not adversely affect listed species. Assessments of the ecological risks of chemical exposures to listed species often rely on the use of surrogate...

  9. Tree structural and species diversities in Okwangwo Forest, Cross ...

    African Journals Online (AJOL)

    Tree species were grouped into abundance classes. A total of 125 tree species belonging to 36 families and 96 genera were recorded in the area with Margaleffs index of species richness of 2.2754. Most (99) of the tree species encountered were threatened/endangered, 23 species were rare with only 3 tree species ...

  10. Estimating tree species richness from forest inventory plot data

    Science.gov (United States)

    Ronald E. McRoberts; Dacia M. Meneguzzo

    2007-01-01

    Montreal Process Criterion 1, Conservation of Biological Diversity, expresses species diversity in terms of number of forest dependent species. Species richness, defined as the total number of species present, is a common metric for analyzing species diversity. A crucial difficulty in estimating species richness from sample data obtained from sources such as inventory...

  11. Identifying ambassador species for conservation marketing

    Directory of Open Access Journals (Sweden)

    E.A. Macdonald

    2017-10-01

    Full Text Available Conservation relies heavily on external funding, much of it from a supportive public. Therefore it is important to know which species are most likely to catalyse such funding. Whilst previous work has looked at the physical attributes that contribute to a species' appeal, no previous studies have tried to examine the extent to which a species' sympatriots might contribute to it's potential as flagship for wider conservation. Therefore, here we estimate ‘flexibility’ and ‘appeal’ scores for all terrestrial mammals (n = 4320 and identify which of these might serve as ambassadors (defined as both highly appealing and flexible. Relatively few mammals (between 240 and 331 emerged as ambassadors, with carnivores featuring heavily in this group (representing 5% of terrestrial mammals but 39% of ambassadors. ‘Top ambassadors’ were defined as those with both flexibility and appeal scores greater than 1 standard deviation above the mean. Less than a quarter of the 20 most endangered and evolutionary distinct species in this study were classed as ambassadors, highlighting the need for surrogate species to catalyse conservation effort in areas with such priority species. This is the first global analysis bringing together flexibility and appeal for all terrestrial mammals, and demonstrates an approach for determining how best to market species in order to achieve maximal conservation gain in a world with urgent conservation need but limited resources.

  12. Design and construction of "synthetic species".

    Directory of Open Access Journals (Sweden)

    Eduardo Moreno

    Full Text Available Synthetic biology is an area of biological research that combines science and engineering. Here, I merge the principles of synthetic biology and regulatory evolution to create a new species with a minimal set of known elements. Using preexisting transgenes and recessive mutations of Drosophila melanogaster, a transgenic population arises with small eyes and a different venation pattern that fulfils the criteria of a new species according to Mayr's Biological Species Concept. The population described here is the first transgenic organism that cannot hybridize with the original wild type population but remains fertile when crossed with other identical transgenic animals. I therefore propose the term "synthetic species" to distinguish it from "natural species", not only because it has been created by genetic manipulation, but also because it may never be able to survive outside the laboratory environment. The use of genetic engineering to design artificial species barriers could help us understand natural speciation and may have practical applications. For instance, the transition from transgenic organisms towards synthetic species could constitute a safety mechanism to avoid the hybridization of genetically modified animals with wild type populations, preserving biodiversity.

  13. Fusarium Species and Their Associated Mycotoxins.

    Science.gov (United States)

    Munkvold, Gary P

    2017-01-01

    The genus Fusarium includes numerous toxigenic species that are pathogenic to plants or humans, and are able to colonize a wide range of environments on earth. The genus comprises around 70 well-known species, identified by using a polyphasic approach, and as many as 300 putative species, according to phylogenetic species concepts; many putative species do not yet have formal names. Fusarium is one of the most economically important fungal genera because of yield loss due to plant pathogenic activity; mycotoxin contamination of food and feed products which often render them unaccep for marketing; and health impacts to humans and livestock, due to consumption of mycotoxins. Among the most important mycotoxins produced by species of Fusarium are the trichothecenes and the fumonisins. Fumonisins cause fatal livestock diseases and are considered potentially carcinogenic mycotoxins for humans, while trichothecenes are potent inhibitors of protein synthesis. This chapter summarizes the main aspects of morphology, pathology, and toxigenicity of the main Fusarium species that colonize different agricultural crops and environments worldwide, and cause mycotoxin contamination of food and feed.

  14. Species coexistence in a changing world.

    Science.gov (United States)

    Valladares, Fernando; Bastias, Cristina C; Godoy, Oscar; Granda, Elena; Escudero, Adrián

    2015-01-01

    The consequences of global change for the maintenance of species diversity will depend on the sum of each species responses to the environment and on the interactions among them. A wide ecological literature supports that these species-specific responses can arise from factors related to life strategies, evolutionary history and intraspecific variation, and also from environmental variation in space and time. In the light of recent advances from coexistence theory combined with mechanistic explanations of diversity maintenance, we discuss how global change drivers can influence species coexistence. We revise the importance of both competition and facilitation for understanding coexistence in different ecosystems, address the influence of phylogenetic relatedness, functional traits, phenotypic plasticity and intraspecific variability, and discuss lessons learnt from invasion ecology. While most previous studies have focused their efforts on disentangling the mechanisms that maintain the biological diversity in species-rich ecosystems such as tropical forests, grasslands and coral reefs, we argue that much can be learnt from pauci-specific communities where functional variability within each species, together with demographic and stochastic processes becomes key to understand species interactions and eventually community responses to global change.

  15. Phylogenetic and Phylogenomic Definition of Rhizopus Species

    Directory of Open Access Journals (Sweden)

    Andrii P. Gryganskyi

    2018-06-01

    Full Text Available Phylogenomic approaches have the potential to improve confidence about the inter-relationships of species in the order Mucorales within the fungal tree of life. Rhizopus species are especially important as plant and animal pathogens and bioindustrial fermenters for food and metabolite production. A dataset of 192 orthologous genes was used to construct a phylogenetic tree of 21 Rhizopus strains, classified into four species isolated from habitats of industrial, medical and environmental importance. The phylogeny indicates that the genus Rhizopus consists of three major clades, with R. microsporus as the basal species and the sister lineage to R. stolonifer and two closely related species R. arrhizus and R. delemar. A comparative analysis of the mating type locus across Rhizopus reveals that its structure is flexible even between different species in the same genus, but shows similarities between Rhizopus and other mucoralean fungi. The topology of single-gene phylogenies built for two genes involved in mating is similar to the phylogenomic tree. Comparison of the total length of the genome assemblies showed that genome size varies by as much as threefold within a species and is driven by changes in transposable element copy numbers and genome duplications.

  16. Recent advances in probabilistic species pool delineations

    Directory of Open Access Journals (Sweden)

    Dirk Nikolaus Karger

    2016-07-01

    Full Text Available A species pool is the set of species that could potentially colonize and establish within a community. It has been a commonly used concept in biogeography since the early days of MacArthur and Wilson’s work on Island Biogeography. Despite their simple and appealing definition, an operational application of species pools is bundled with a multitude of problems, which have often resulted in arbitrary decisions and workarounds when defining species pools. Two recently published papers address the operational problems of species pool delineations, and show ways of delineating them in a probabilistic fashion. In both papers, species pools were delineated using a process-based, mechanistical approach, which opens the door for a multitude of new applications in biogeography. Such applications include detecting the hidden signature of biotic interactions, disentangling the geographical structure of community assembly processes, and incorporating a temporal extent into species pools. Although similar in their conclusions, both ‘probabilistic approaches’ differ in their implementation and definitions. Here I give a brief overview of the differences and similarities of both approaches, and identify the challenges and advantages in their application.

  17. Pushing the pace of tree species migration.

    Directory of Open Access Journals (Sweden)

    Eli D Lazarus

    Full Text Available Plants and animals have responded to past climate changes by migrating with habitable environments, sometimes shifting the boundaries of their geographic ranges by tens of kilometers per year or more. Species migrating in response to present climate conditions, however, must contend with landscapes fragmented by anthropogenic disturbance. We consider this problem in the context of wind-dispersed tree species. Mechanisms of long-distance seed dispersal make these species capable of rapid migration rates. Models of species-front migration suggest that even tree species with the capacity for long-distance dispersal will be unable to keep pace with future spatial changes in temperature gradients, exclusive of habitat fragmentation effects. Here we present a numerical model that captures the salient dynamics of migration by long-distance dispersal for a generic tree species. We then use the model to explore the possible effects of assisted colonization within a fragmented landscape under a simulated tree-planting scheme. Our results suggest that an assisted-colonization program could accelerate species-front migration rates enough to match the speed of climate change, but such a program would involve an environmental-sustainability intervention at a massive scale.

  18. Cryptic species as a window into the paradigm shift of the species concept.

    Science.gov (United States)

    Fišer, Cene; Robinson, Christopher T; Malard, Florian

    2018-02-01

    The species concept is the cornerstone of biodiversity science, and any paradigm shift in the delimitation of species affects many research fields. Many biologists now are embracing a new "species" paradigm as separately evolving populations using different delimitation criteria. Individual criteria can emerge during different periods of speciation; some may never evolve. As such, a paradigm shift in the species concept relates to this inherent heterogeneity in the speciation process and species category-which is fundamentally overlooked in biodiversity research. Cryptic species fall within this paradigm shift: they are continuously being reported from diverse animal phyla but are poorly considered in current tests of ecological and evolutionary theory. The aim of this review is to integrate cryptic species in biodiversity science. In the first section, we address that the absence of morphological diversification is an evolutionary phenomenon, a "process" counterpart to the long-studied mechanisms of morphological diversification. In the next section regarding taxonomy, we show that molecular delimitation of cryptic species is heavily biased towards distance-based methods. We also stress the importance of formally naming of cryptic species for better integration into research fields that use species as units of analysis. Finally, we show that incorporating cryptic species leads to novel insights regarding biodiversity patterns and processes, including large-scale biodiversity assessments, geographic variation in species distribution and species coexistence. It is time for incorporating multicriteria species approaches aiming to understand speciation across space and taxa, thus allowing integration into biodiversity conservation while accommodating for species uncertainty. © 2018 John Wiley & Sons Ltd.

  19. Review: Allee effects in social species.

    Science.gov (United States)

    Angulo, Elena; Luque, Gloria M; Gregory, Stephen D; Wenzel, John W; Bessa-Gomes, Carmen; Berec, Ludek; Courchamp, Franck

    2018-01-01

    Allee effects have important implications for many aspects of basic and applied ecology. The benefits of aggregation of conspecific individuals are central to Allee effects, which have led to the widely held assumption that social species are more prone to Allee effects. Robust evidence for this assumption, however, remains rare. Furthermore, previous research on Allee effects has failed to adequately address the consequences of the different levels of organisation within social species' populations. Here, we review available evidence of Allee effects and model the role of demographic and behavioural factors that may combine to dampen or strengthen Allee effects in social species. We use examples across various species with contrasting social structure, including carnivores, bats, primates and eusocial insects. Building on this, we provide a conceptual framework that allows for the integration of different Allee effects in social species. Social species are characterised by nested levels of organisation. The benefits of cooperation, measured by mean individual fitness, can be observed at both the population and group levels, giving rise to "population level" and "group level" Allee effects respectively. We also speculate on the possibility of a third level, reporting per capita benefits for different individuals within a group (e.g. castes in social insects). We show that group size heterogeneity and intergroup interactions affect the strength of population-level demographic Allee effects. Populations with higher group size heterogeneity and in which individual social groups cooperate demonstrate the weakest Allee effects and may thus provide an explanation for why extinctions due to Allee effects are rare in social species. More adequately accounting for Allee effects in social species will improve our understanding of the ecological and evolutionary implications of cooperation in social species. © 2017 The Authors. Journal of Animal Ecology © 2017 British

  20. Economics of Harmful Invasive Species: A Review

    Directory of Open Access Journals (Sweden)

    George Marbuah

    2014-07-01

    Full Text Available The purpose of this study is to review theoretical and empirical findings in economics with respect to the challenging question of how to manage invasive species. The review revealed a relatively large body of literature on the assessment of damage costs of invasive species; single species and groups of species at different geographical scales. However, the estimated damage costs show large variation, from less than 1 million USD to costs corresponding to 12% of gross domestic product, depending on the methods employed, geographical scale, and scope with respect to inclusion of different species. Decisions regarding optimal management strategies, when to act in the invasion chain and which policy to choose, have received much less attention in earlier years, but have been subject to increasing research during the last decade. More difficult, but also more relevant policy issues have been raised, which concern the targeting in time and space of strategies under conditions of uncertainty. In particular, the weighting of costs and benefits from early detection and mitigation against the uncertain avoidance of damage with later control, when the precision in targeting species is typically greater is identified as a key challenge. The role of improved monitoring for detecting species and their spread and damage has been emphasized, but questions remain on how to achieve this in practice. This is in contrast to the relatively large body of literature on policies for mitigating dispersal by trade, which is regarded as one of the most important vectors for the spread of invasive species. On the other hand, the literature on how to mitigate established species, by control or adaptation, is much more scant. Studies evaluating causes for success or failure of policies against invasive in practice are in principal non-existing.

  1. An updated checklist of mosquito species (Diptera: Culicidae) from Madagascar

    Science.gov (United States)

    Tantely, Michaël Luciano; Le Goff, Gilbert; Boyer, Sébastien; Fontenille, Didier

    2016-01-01

    An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species). This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species), Aedes (35 species), Anopheles (26 species), Coquillettidia (3 species), Culex (at least 50 species), Eretmapodites (4 species), Ficalbia (2 species), Hodgesia (at least one species), Lutzia (one species), Mansonia (2 species), Mimomyia (22 species), Orthopodomyia (8 species), Toxorhynchites (6 species), and Uranotaenia (73 species). Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%). Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27%) with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar. PMID:27101839

  2. An updated checklist of mosquito species (Diptera: Culicidae from Madagascar

    Directory of Open Access Journals (Sweden)

    Tantely Michaël Luciano

    2016-01-01

    Full Text Available An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species. This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species, Aedes (35 species, Anopheles (26 species, Coquillettidia (3 species, Culex (at least 50 species, Eretmapodites (4 species, Ficalbia (2 species, Hodgesia (at least one species, Lutzia (one species, Mansonia (2 species, Mimomyia (22 species, Orthopodomyia (8 species, Toxorhynchites (6 species, and Uranotaenia (73 species. Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%. Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27% with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar.

  3. Cross-species amplification of 105 Lolium perenne SSR loci in 23 species within the Poaceae

    DEFF Research Database (Denmark)

    Jensen, Louise Bach; Holm, Preben Bach; Lübberstedt, Thomas

    2007-01-01

    Amplification of 105 Lolium perenne SSR markers was studied in 23 grass species representing seven tribes from three subfamilies of Poaceae. Twelve of the SSR markers are published for the first time. Between 2% and 96% of the SSR markers could be amplified within a given species. A subset of eight...... SSR markers was evaluated for polymorphism across nine of the 23 grass species. Four to seven of the markers were polymorphic within each species, with an average detection of 2.4 alleles per species....

  4. Dna c-values of 20 invasive alien species and 3 native species in south china

    Directory of Open Access Journals (Sweden)

    Gong Ni

    2014-01-01

    Full Text Available Cultivated fields and forests in South China are experiencing serious damage due to invasive alien plants. We investigated the relation between DNA C-values and invasiveness. The DNA C-values of 23 species ranged from 0.39 pg to 3.37 pg. Herbs, perennials and native species had higher mean DNA C-values than shrubs, annuals and invasive alien species. DNA C-values decreased with increasing invasiveness. Paederia scandens, a harmful native species, has the lowest DNA C-value among the perennials, indicating that native species with low nuclear content may also possess an invasive potential.

  5. Metabolite production by species of Stemphylium

    DEFF Research Database (Denmark)

    Olsen, Kresten Jon Kromphardt; Rossman, Amy; Andersen, Birgitte

    2018-01-01

    metabolites were found to be important for distinguishing species, while some unknown metabolites were also found to have important roles in distinguishing species of Stemphylium. This study is the first of its kind to investigate the chemical potential of Stemphylium across the whole genus.......Morphology and phylogeny has been used to distinguish members of the plant pathogenic fungal genus Stemphylium. A third method for distinguishing species is by chemotaxonomy. The main goal of the present study was to investigate the chemical potential of Stemphylium via HPLC-UV-MS analysis, while...

  6. Reservoirs of Non-baumannii Acinetobacter Species

    Science.gov (United States)

    Al Atrouni, Ahmad; Joly-Guillou, Marie-Laure; Hamze, Monzer; Kempf, Marie

    2016-01-01

    Acinetobacter spp. are ubiquitous gram negative and non-fermenting coccobacilli that have the ability to occupy several ecological niches including environment, animals and human. Among the different species, Acinetobacter baumannii has evolved as global pathogen causing wide range of infection. Since the implementation of molecular techniques, the habitat and the role of non-baumannii Acinetobacter in human infection have been elucidated. In addition, several new species have been described. In the present review, we summarize the recent data about the natural reservoir of non-baumannii Acinetobacter including the novel species that have been described for the first time from environmental sources and reported during the last years. PMID:26870013

  7. Tree Species Identity Shapes Earthworm Communities

    DEFF Research Database (Denmark)

    Schelfhout, Stephanie; Mertens, Jan; Verheyen, Kris

    2017-01-01

    Earthworms are key organisms in forest ecosystems because they incorporate organic material into the soil and affect the activity of other soil organisms. Here, we investigated how tree species affect earthworm communities via litter and soil characteristics. In a 36-year old common garden...... of soil and foliar litter, and determined the forest floor turnover rate and the density and biomass of the earthworm species occurring in the stands. Tree species significantly affected earthworm communities via leaf litter and/or soil characteristics. Anecic earthworms were abundant under Fraxinus, Acer...

  8. Fort Collins Science Center: Invasive Species Science

    Science.gov (United States)

    Stohlgren, Tom

    2004-01-01

    Invasive, non-native species of plants, animals, and disease organisms adversely affect the ecosystems they enter. Like "biological wildfires," they can quickly spread, and they affect nearly all terrestrial and aquatic ecosystems. Invasive species have become the greatest environmental challenge of the 21st century in terms of economic, environmental, and human health costs, with an estimated impact in the U.S. of over $138 billion per year. Managers of Department of the Interior and other public and private lands and waters rank invasive species as their top resource management problem.

  9. Fatty acid composition of forage herb species

    DEFF Research Database (Denmark)

    Warner, D.; Jensen, Søren Krogh; Cone, J.W.

    2010-01-01

    The use of alternative forage species in grasslands for intensive livestock production is receiving renewed attention. Data on fatty acid composition of herbs are scarce, so four herbs (Plantago lanceolata, Achillea millefolium, Cichorium intybus, Pastinaca sativa) and one grass species (timothy......, Phleum pratense) were sown in a cutting trial. The chemical composition and concentration of fatty acids (FA) of individual species were determined during the growing season. Concentrations of crude protein and FA were generally higher in the herbs than in timothy. C. intybus had the highest nutritive...

  10. Species Diversity Enhances Predator Growth Rates

    International Nuclear Information System (INIS)

    Olson, M.H.; Jacobs, R.P.; O'Donnell, E.B.

    2007-01-01

    Predators can be important top-down regulators of community structure and are known to have both positive and negative effects on species diversity. However, little is known about the reciprocal effects of species diversity on predators. Across a set of 80 lakes in Connecticut, USA, we found a strong positive correlation between prey species diversity (using the Shannon-Weiner Diversity Index) and growth rates of largemouth bass (Micropterus salmoides). This correlation was strongest for small predators and decreased with body size. Although the underlying mechanisms are not known, the correlation is not driven by total fish abundance, predator abundance, or productivity.

  11. Predictions For New, Exotic Actinide Species

    International Nuclear Information System (INIS)

    Pyykko, P.

    2002-01-01

    The approach. New, simple chemical species can be predicted by studying isoelectronic series using ab initio quantum chemistry. We currently use in most cases relativistic pseudopotentials and handle the electron correlation using density functional theory (DFT) or wave-function-based methods, from MP2 to CCSD(T). Typical codes are Gaussian 98, Turbomole or MolCas. For full four-component Dirac-Fock calculations, the DREAMS code of K. G. Dyall has been utilized. For mapping out the possible new species, complete maps of all possibilities are made, whenever possible, and the new species typically occur along the coast-line of the 'island of stability' of already known species

  12. antimicrobial susceptibility pattern of Salmonella species

    African Journals Online (AJOL)

    user

    GLOBAL JOURNAL OF COMMUNITY MEDICINE VOL. 2 NO. 1 & 2 2009: 5 - ... This study is a review of the contemporary antimicrobial susceptibility pattern of. Salmonella species. ... south-east Asia, parts of Latin America, the. Caribbean, and ...

  13. Metabolomic analysis of three Mollicute species.

    Directory of Open Access Journals (Sweden)

    Anna A Vanyushkina

    Full Text Available We present a systematic study of three bacterial species that belong to the class Mollicutes, the smallest and simplest bacteria, Spiroplasma melliferum, Mycoplasma gallisepticum, and Acholeplasma laidlawii. To understand the difference in the basic principles of metabolism regulation and adaptation to environmental conditions in the three species, we analyzed the metabolome of these bacteria. Metabolic pathways were reconstructed using the proteogenomic annotation data provided by our lab. The results of metabolome, proteome and genome profiling suggest a fundamental difference in the adaptation of the three closely related Mollicute species to stress conditions. As the transaldolase is not annotated in Mollicutes, we propose variants of the pentose phosphate pathway catalyzed by annotated enzymes for three species. For metabolite detection we employed high performance liquid chromatography coupled with mass spectrometry. We used liquid chromatography method - hydrophilic interaction chromatography with silica column - as it effectively separates highly polar cellular metabolites prior to their detection by mass spectrometer.

  14. Luminescence properties of uranyl-acetate species

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, Hannes; Moll, Henry [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Inst. of Resource Ecology; Stumpf, Thorsten [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry

    2017-06-01

    Time-resolved laser-induced fluorescence spectroscopy (TRLFS) was applied to characterize uranium(VI)- acetate species based on their luminescence properties. In contrast to previous interpretations, no indications were detected for the existence of the 1: 3 complex.

  15. Influence of estuaries on shelf foraminiferal species

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.

    Dabhol-bhatkal stretch of the west coast of India is marked by a number of estuaries. Cavarotalia annectens is selected to monitor the influence of these estuaries on the inner shelf foraminiferal fauna. The percentage distribution of this species...

  16. CONSERVATION METHODS OF ENDANGERED SPECIES GUNDU ...

    African Journals Online (AJOL)

    user

    Department of Forestry, Akperan Orshi College of Agriculture Yandev, Gboko ... conservation measure, an endangered species finally goes into extinction, that ... either for tourism, scientific studies/ .... economic, educational, scientific, cultural.

  17. New trends in species distribution modelling

    Science.gov (United States)

    Zimmermann, Niklaus E.; Edwards, Thomas C.; Graham, Catherine H.; Pearman, Peter B.; Svenning, Jens-Christian

    2010-01-01

    Species distribution modelling has its origin in the late 1970s when computing capacity was limited. Early work in the field concentrated mostly on the development of methods to model effectively the shape of a species' response to environmental gradients (Austin 1987, Austin et al. 1990). The methodology and its framework were summarized in reviews 10–15 yr ago (Franklin 1995, Guisan and Zimmermann 2000), and these syntheses are still widely used as reference landmarks in the current distribution modelling literature. However, enormous advancements have occurred over the last decade, with hundreds – if not thousands – of publications on species distribution model (SDM) methodologies and their application to a broad set of conservation, ecological and evolutionary questions. With this special issue, originating from the third of a set of specialized SDM workshops (2008 Riederalp) entitled 'The Utility of Species Distribution Models as Tools for Conservation Ecology', we reflect on current trends and the progress achieved over the last decade.

  18. Cooperation and the Endangered Species Act

    International Nuclear Information System (INIS)

    Palmer, S.C.

    1991-01-01

    Passage of the Endangered Species Act in 1973 set the stage for some of the nations most polemic environmental battles. One of these is in the Colorado River Basin which is home to four native and rare fish species. Acrimonious confrontation has characterized the consultations under the ESA regarding these fish species. In 1983, the U.S. Fish and Wildlife Service announced that no new water depletions such as for hydropower plants, from the Upper Colorado River Basin would be allowed. This created no small stir among basin states and water developers and a negotiated solution was sought. The result was the Recovery Implementation Program for Endangered Fish Species in the Upper Colorado River Basin. This paper reports that models of political negotiation indicate conceptually, that the Recovery Program with its decisions made by unanimity of consensus, its open process and sharing of information, its shared budget and users fees, is a vehicle of political compromise and cooperation

  19. Bioeconomic analysis supports the endangered species act.

    Science.gov (United States)

    Salau, Kehinde R; Fenichel, Eli P

    2015-10-01

    The United States Endangered Species Act (ESA) was enacted to protect and restore declining fish, wildlife, and plant populations. The ESA mandates endangered species protection irrespective of costs. This translates to the restriction of activities that harm endangered populations. We discuss criticisms of the ESA in the context of public land management and examine under what circumstance banning non-conservation activity on multiple use federal lands can be socially optimal. We develop a bioeconomic model to frame the species management problem under the ESA and identify scenarios where ESA-imposed regulations emerge as optimal strategies. Results suggest that banning harmful activities is a preferred strategy when valued endangered species are in decline or exposed to poor habitat quality. However, it is not optimal to sustain such a strategy in perpetuity. An optimal plan involves a switch to land-use practices characteristic of habitat conservation plans.

  20. The Drosophila bipectinata species complex: phylogenetic ...

    Indian Academy of Sciences (India)

    PARUL BANERJEE

    c Indian Academy of Sciences. RESEARCH ARTICLE. The Drosophila bipectinata species complex: phylogenetic relationship among different members based on chromosomal variations. PARUL BANERJEE and BASHISTH N. SINGH. ∗. Genetics Laboratory, Department of Zoology, Banaras Hindu University, Varanasi ...

  1. A cross-species alignment tool (CAT)

    DEFF Research Database (Denmark)

    Li, Heng; Guan, Liang; Liu, Tao

    2007-01-01

    BACKGROUND: The main two sorts of automatic gene annotation frameworks are ab initio and alignment-based, the latter splitting into two sub-groups. The first group is used for intra-species alignments, among which are successful ones with high specificity and speed. The other group contains more...... sensitive methods which are usually applied in aligning inter-species sequences. RESULTS: Here we present a new algorithm called CAT (for Cross-species Alignment Tool). It is designed to align mRNA sequences to mammalian-sized genomes. CAT is implemented using C scripts and is freely available on the web...... at http://xat.sourceforge.net/. CONCLUSIONS: Examined from different angles, CAT outperforms other extant alignment tools. Tested against all available mouse-human and zebrafish-human orthologs, we demonstrate that CAT combines the specificity and speed of the best intra-species algorithms, like BLAT...

  2. Marine linefish programme priority species list

    CSIR Research Space (South Africa)

    Wallace, JH

    1983-05-01

    Full Text Available in Durban in April 1982. For each species, information is presented on; distribution, angling status, preferred habitat, growth, reproduction, catch statistics and further research work required. The publication is intended to act as a working document...

  3. Germplasm characterization of three jabuticaba tree species

    Directory of Open Access Journals (Sweden)

    Moeses Andrigo Danner

    2011-09-01

    Full Text Available The purpose of this study was to characterize cultivated genotypes of three jabuticaba species (Plinia cauliflora, P. trunciflora, and P. jaboticaba. Phenology and fruit growth, as well as leaf, flower and fruit traits were evaluated. Variability in all traits was observed among genotypes of the three jabuticaba species. The trait peduncle size is indicated for differentiation of the three species under study. The leaf and fruit sizes of the genotypes P. trunciflora 3, P. trunciflora 4, P. trunciflora 5 and P. jaboticaba 1 differ from those described in the literature for these species, indicating the formation of ecotypes. Jabuticaba fruit skin contains high anthocyanin and flavonoid concentrations, with potential use in food and pharmaceutical industries.

  4. Density of Threatened and Endangered Species

    Data.gov (United States)

    California Natural Resource Agency — A compiled density of threatened and endangered species built around 2000m wide hexagonal cells. The dataset was created by generating a blank hex grid, intersecting...

  5. Invasive species unchecked by climate - response

    DEFF Research Database (Denmark)

    Burrows, Michael T.; Schoeman, David S.; Duarte, Carlos M.

    2012-01-01

    environments. This may be particularly true in the world's boreal oceans as melting sea ice facilitates new migratory passages between the Atlantic and Pacific Oceans. Moreover, as the ebb and flow of biodiversity intensifies under anthropogenic climate change, novel climates and communities of species......Hulme points out that observed rates of range expansion by invasive alien species are higher than the median speed of isotherm movement over the past 50 years, which in turn has outpaced the rates of climate-associated range changes of marine and terrestrial species. This is not surprising, given...... of climate-change-induced range shifts between native and alien species are meaningful only after the initial invasive spread has reached a stable range boundary. A focus on regions with high velocities of climate change, and on regions such as the tropics where novel thermal niches are being created, should...

  6. Osmoregulation in three species of Ambassidae (Osteichthyes ...

    African Journals Online (AJOL)

    1989-07-25

    Jul 25, 1989 ... the temperature tolerance ranges of the three species (Martin. 1988) suggest that ..... dependent on the period spent in freshwater (Holliday 1971;. Nordlie 1985). .... GILLES, R. 1975. Mechanisms of ion and osmoregulation.

  7. Community structure informs species geographic distributions

    KAUST Repository

    Montesinos-Navarro, Alicia; Estrada, Alba; Font, Xavier; Matias, Miguel G.; Meireles, Catarina; Mendoza, Manuel; Honrado, Joao P.; Prasad, Hari D.; Vicente, Joana R.; Early, Regan

    2018-01-01

    spatial resolution. However, survival of individuals is determined by processes that happen at small spatial scales. The relative abundance of coexisting species (i.e. 'community structure') reflects assembly processes occurring at small scales

  8. Sensory quality criteria for five fish species

    DEFF Research Database (Denmark)

    Warm, Karin; Nielsen, Jette; Hyldig, Grethe

    2000-01-01

    Sensory profiling has been used to develop one sensory vocabulary for five fish species: cod (Gadus morhua), saithe (Pollachius virens), rainbow trout (Salmo gardineri), herring (Clupea harengus) and flounder (Platichthys flessus). A nine- member trained panel assessed 18 samples with variation i...... variation and by presenting references, panel discussions and interpreting plots from multivariate data analysis. The developed profile can be used as a sensory wheel for these species, and with minor changes it may be adapted to similar species......Sensory profiling has been used to develop one sensory vocabulary for five fish species: cod (Gadus morhua), saithe (Pollachius virens), rainbow trout (Salmo gardineri), herring (Clupea harengus) and flounder (Platichthys flessus). A nine- member trained panel assessed 18 samples with variation...

  9. On two new species of Siriella (Mysidacea)

    Digital Repository Service at National Institute of Oceanography (India)

    Panampunnayil, S.U.

    Descriptions of two new mysids, Siriella africana ap. nov. collected from Agulhas Bank and S. intermedia sp. nov. collected from Laccadives are given. The present paper contains observations on two species of mysidacea collected from the Indian...

  10. Quantifying Temporal Genomic Erosion in Endangered Species.

    Science.gov (United States)

    Díez-Del-Molino, David; Sánchez-Barreiro, Fatima; Barnes, Ian; Gilbert, M Thomas P; Dalén, Love

    2018-03-01

    Many species have undergone dramatic population size declines over the past centuries. Although stochastic genetic processes during and after such declines are thought to elevate the risk of extinction, comparative analyses of genomic data from several endangered species suggest little concordance between genome-wide diversity and current population sizes. This is likely because species-specific life-history traits and ancient bottlenecks overshadow the genetic effect of recent demographic declines. Therefore, we advocate that temporal sampling of genomic data provides a more accurate approach to quantify genetic threats in endangered species. Specifically, genomic data from predecline museum specimens will provide valuable baseline data that enable accurate estimation of recent decreases in genome-wide diversity, increases in inbreeding levels, and accumulation of deleterious genetic variation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Endangered Species Litigation and Associated Pesticide Limitations

    Science.gov (United States)

    EPA has been subject to several citizen suits. As a result we have conducted scientific assessments and made effects determinations for various pesticide products as related to specific species of concern.

  12. ESUSA: US endangered species distribution file

    Energy Technology Data Exchange (ETDEWEB)

    Nagy, J.; Calef, C.E.

    1979-10-01

    This report describes a file containing distribution data on endangered species of the United States of Federal concern pursuant to the Endangered Species Act of 1973. Included for each species are (a) the common name, (b) the scientific name, (c) the family, (d) the group (mammal, bird, etc.), (e) Fish and Wildlife Service (FWS) listing and recovery priorities, (f) the Federal legal status, (g) the geographic distribution by counties or islands, (h) Federal Register citations and (i) the sources of the information on distribution of the species. Status types are endangered, threatened, proposed, formally under review, candidate, deleted, and rejected. Distribution is by Federal Information Processing Standard (FIPS) county code and is of four types: designated critical habitat, present range, potential range, and historic range.

  13. EXTRACTION AND ANTIOXIDANT ACTIVITIES OF TWO SPECIES ...

    African Journals Online (AJOL)

    2013-06-30

    Jun 30, 2013 ... Origanum vulgare were investigated and also the total phenolic and ... species majorana, and vulgare respectively; also the DPPH of essential oil of Origanum ... inflammatory, antimicrobial and antioxidant activities[10] .

  14. Clonal growth and plant species abundance.

    Science.gov (United States)

    Herben, Tomáš; Nováková, Zuzana; Klimešová, Jitka

    2014-08-01

    Both regional and local plant abundances are driven by species' dispersal capacities and their abilities to exploit new habitats and persist there. These processes are affected by clonal growth, which is difficult to evaluate and compare across large numbers of species. This study assessed the influence of clonal reproduction on local and regional abundances of a large set of species and compared the predictive power of morphologically defined traits of clonal growth with data on actual clonal growth from a botanical garden. The role of clonal growth was compared with the effects of seed reproduction, habitat requirements and growth, proxied both by LHS (leaf-height-seed) traits and by actual performance in the botanical garden. Morphological parameters of clonal growth, actual clonal reproduction in the garden and LHS traits (leaf-specific area - height - seed mass) were used as predictors of species abundance, both regional (number of species records in the Czech Republic) and local (mean species cover in vegetation records) for 836 perennial herbaceous species. Species differences in habitat requirements were accounted for by classifying the dataset by habitat type and also by using Ellenberg indicator values as covariates. After habitat differences were accounted for, clonal growth parameters explained an important part of variation in species abundance, both at regional and at local levels. At both levels, both greater vegetative growth in cultivation and greater lateral expansion trait values were correlated with higher abundance. Seed reproduction had weaker effects, being positive at the regional level and negative at the local level. Morphologically defined traits are predictive of species abundance, and it is concluded that simultaneous investigation of several such traits can help develop hypotheses on specific processes (e.g. avoidance of self-competition, support of offspring) potentially underlying clonal growth effects on abundance. Garden

  15. The Endangered Species Act and Sound Science

    Science.gov (United States)

    2006-10-05

    population segment” under ESA? ! If a species is wide-ranging and begins, on its own, to reappear in an area it once occupied (as with a few wolves in... Yellowstone ), should these animals be regarded as a “resident population” for purposes of ESA? ! Should a formerly widely-distributed species (such as bald... wolves ), and is delisted as soon as possible (as with bald eagles and Florida panthers). Representatives of many scientific or environmental

  16. Invasive Species - A Threat to the Homeland?

    Science.gov (United States)

    2003-04-07

    species of weeds, diseases and organisms on both my farm and the surrounding woodlands. Some of these species include soybean cyst nematode, soybean aphid ...natural enemies in their new environment. Parasites, pathogens , or predators that would inhibit or limit their spread are few or non-existent. In...tested, and fielded to control the genetically modified organism. Serums would be less effective, and diagnosis of human pathogens could change and

  17. Isoprene emission from tropical tree species

    International Nuclear Information System (INIS)

    Padhy, P.K.; Varshney, C.K.

    2005-01-01

    Foliar emission of isoprene was measured in nine commonly growing tree species of Delhi, India. Dynamic flow enclosure technique was used and gas samples were collected onto Tenax-GC/Carboseive cartridges, which were then attached to the sample injection system in the gas chromatograph (GC). Eluting compounds were analysed using a flame ionisation detector (FID). Out of the nine tree species, isoprene emission was found in six species (Eucalyptus sp., Ficus benghalensis, Ficus religiosa, Mangifera indica, Melia azedarach, and Syzygium jambolanum), whereas, in the remaining three tree species (Alstonia scholaris, Azadirachta indica, and Cassia fistula) no isoprene emission was detected or the levels of emission were negligible or below the detection limit (BDL). Among six tree species, the highest hourly emission (10.2±6.8 μg g -1 leaf dry weight, average of five seasons) was observed in Ficus religiosa, while minimum emission was from Melia azedarach (2.2±4.9 μg g -1 leaf dry weight, average of five seasons). Isoprene emission (average of six species), over five seasons, was found to vary between 3.9 and 8.5 μg g -1 leaf dry weight during the rainy season. In addition, significant diurnal variation in isoprene emission was observed in each species. The preliminary estimate made in this study on the annual biogenic VOC emission from India may probably be the first of its kind from this part of the world. - Isoprene flux (diurnal and seasonal) from some tropical tree species was estimated and a regional comparison was made

  18. Isoprene emission from tropical tree species

    Energy Technology Data Exchange (ETDEWEB)

    Padhy, P.K. [School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110 067 (India)]. E-mail: padhypk2003@yahoo.com; Varshney, C.K. [School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110 067 (India)

    2005-05-01

    Foliar emission of isoprene was measured in nine commonly growing tree species of Delhi, India. Dynamic flow enclosure technique was used and gas samples were collected onto Tenax-GC/Carboseive cartridges, which were then attached to the sample injection system in the gas chromatograph (GC). Eluting compounds were analysed using a flame ionisation detector (FID). Out of the nine tree species, isoprene emission was found in six species (Eucalyptus sp., Ficus benghalensis, Ficus religiosa, Mangifera indica, Melia azedarach, and Syzygium jambolanum), whereas, in the remaining three tree species (Alstonia scholaris, Azadirachta indica, and Cassia fistula) no isoprene emission was detected or the levels of emission were negligible or below the detection limit (BDL). Among six tree species, the highest hourly emission (10.2{+-}6.8 {mu}g g{sup -1} leaf dry weight, average of five seasons) was observed in Ficus religiosa, while minimum emission was from Melia azedarach (2.2{+-}4.9 {mu}g g{sup -1} leaf dry weight, average of five seasons). Isoprene emission (average of six species), over five seasons, was found to vary between 3.9 and 8.5 {mu}g g{sup -1} leaf dry weight during the rainy season. In addition, significant diurnal variation in isoprene emission was observed in each species. The preliminary estimate made in this study on the annual biogenic VOC emission from India may probably be the first of its kind from this part of the world. - Isoprene flux (diurnal and seasonal) from some tropical tree species was estimated and a regional comparison was made.

  19. The ethics of reviving long extinct species.

    Science.gov (United States)

    Sandler, Ronald

    2014-04-01

    There now appears to be a plausible pathway for reviving species that have been extinct for several decades, centuries, or even millennia. I conducted an ethical analysis of de-extinction of long extinct species. I assessed several possible ethical considerations in favor of pursuing de-extinction: that it is a matter of justice; that it would reestablish lost value; that it would create new value; and that society needs it as a conservation last resort. I also assessed several possible ethical arguments against pursuing de-extinction: that it is unnatural; that it could cause animal suffering; that it could be ecologically problematic or detrimental to human health; and that it is hubristic. There are reasons in favor of reviving long extinct species, and it can be ethically acceptable to do so. However, the reasons in favor of pursuing de-extinction do not have to do with its usefulness in species conservation; rather, they concern the status of revived species as scientific and technological achievements, and it would be ethically problematic to promote de-extinction as a significant conservation strategy, because it does not prevent species extinctions, does not address the causes of extinction, and could be detrimental to some species conservation efforts. Moreover, humanity does not have a responsibility or obligation to pursue de-extinction of long extinct species, and reviving them does not address any urgent problem. Therefore, legitimate ecological, political, animal welfare, legal, or human health concerns associated with a de-extinction (and reintroduction) must be thoroughly addressed for it to be ethically acceptable. © 2013 Society for Conservation Biology.

  20. Relation of chironomids with Aeromonas species

    Directory of Open Access Journals (Sweden)

    Sivan eLaviad

    2016-05-01

    Full Text Available Chironomids (Diptera: Chironomidae, also known as non-biting midges, are one of the most abundant groups of insects in aquatic habitats. They undergo a complete metamorphosis of four life stages of which three are aquatic (egg, larva, pupa, and the adult emerges into the air. Chironomids serve as a natural reservoir of Aeromonas and Vibrio cholerae species. Here we review existing knowledge about the mutual relations between Aeromonas species and chironomids. Using 454-pyrosequencing of the 16S rRNA gene, we found that the prevalence of Aeromonas species in the insects’ egg masses and larvae was 1.6% and 3.3% of the insects’ endogenous microbiota, respectively. Aeromonas abundance per egg mass remained stable during a six-month period of bacterial monitoring. Different Aeromonas species were isolated and some demonstrated the ability to degrade the insect’s egg masses and to prevent eggs hatching. Chitinase was identified as the enzyme responsible for the egg mass degradation. Different Aeromonas species isolated from chironomids demonstrated the potential to protect their host from toxic metals. Aeromonas is a causative agent of fish infections. Fish are frequently recorded as feeding on chironomids. Thus, fish might be infected with Aeromonas species via chironomid consumption. Aeromonas strains are also responsible for causing gastroenteritis and wound infections in humans. Different virulence genes were identified in Aeromonas species isolated from chironomids. Chironomids may infest drinking water reservoirs, hence be the source of pathogenic Aeromonas strains in drinking water. Chironomids and Aeromonas species have a complicated mutual relationship.

  1. Phylogeny and species traits predict bird detectability

    Science.gov (United States)

    Solymos, Peter; Matsuoka, Steven M.; Stralberg, Diana; Barker, Nicole K. S.; Bayne, Erin M.

    2018-01-01

    Avian acoustic communication has resulted from evolutionary pressures and ecological constraints. We therefore expect that auditory detectability in birds might be predictable by species traits and phylogenetic relatedness. We evaluated the relationship between phylogeny, species traits, and field‐based estimates of the two processes that determine species detectability (singing rate and detection distance) for 141 bird species breeding in boreal North America. We used phylogenetic mixed models and cross‐validation to compare the relative merits of using trait data only, phylogeny only, or the combination of both to predict detectability. We found a strong phylogenetic signal in both singing rates and detection distances; however the strength of phylogenetic effects was less than expected under Brownian motion evolution. The evolution of behavioural traits that determine singing rates was found to be more labile, leaving more room for species to evolve independently, whereas detection distance was mostly determined by anatomy (i.e. body size) and thus the laws of physics. Our findings can help in disentangling how complex ecological and evolutionary mechanisms have shaped different aspects of detectability in boreal birds. Such information can greatly inform single‐ and multi‐species models but more work is required to better understand how to best correct possible biases in phylogenetic diversity and other community metrics.

  2. The temporal variability of species densities

    International Nuclear Information System (INIS)

    Redfearn, A.; Pimm, S.L.

    1993-01-01

    Ecologists use the term 'stability' to mean to number of different things (Pimm 1984a). One use is to equate stability with low variability in population density over time (henceforth, temporal variability). Temporal variability varies greatly from species to species, so what effects it? There are at least three sets of factors: the variability of extrinsic abiotic factors, food web structure, and the intrinsic features of the species themselves. We can measure temporal variability using at least three statistics: the coefficient of variation of density (CV); the standard deviation of the logarithms of density (SDL); and the variance in the differences between logarithms of density for pairs of consecutive years (called annual variability, hence AV, b y Wolda 1978). There are advantages and disadvantages to each measure (Williamson 1984), though in our experience, the measures are strongly correlated across sets of taxonomically related species. The increasing availability of long-term data sets allows one to calculate these statistics for many species and so to begin to understand the various causes of species differences in temporal variability

  3. Malaria vector species in Colombia: a review

    Directory of Open Access Journals (Sweden)

    James Montoya-Lerma

    2011-08-01

    Full Text Available Here we present a comprehensive review of the literature on the vectorial importance of the major Anopheles malaria vectors in Colombia. We provide basic information on the geographical distribution, altitudinal range, immature habitats, adult behaviour, feeding preferences and anthropophily, endophily and infectivity rates. We additionally review information on the life cycle, longevity and population fluctuation of Colombian Anopheles species. Emphasis was placed on the primary vectors that have been epidemiologically incriminated in malaria transmission: Anopheles darlingi, Anopheles albimanus and Anopheles nuneztovari. The role of a selection of local, regional or secondary vectors (e.g., Anopheles pseudopunctipennis and Anopheles neivai is also discussed. We highlight the importance of combining biological, morphological and molecular data for the correct taxonomical determination of a given species, particularly for members of the species complexes. We likewise emphasise the importance of studying the bionomics of primary and secondary vectors along with an examination of the local conditions affecting the transmission of malaria. The presence and spread of the major vectors and the emergence of secondary species capable of transmitting human Plasmodia are of great interest. When selecting control measures, the anopheline diversity in the region must be considered. Variation in macroclimate conditions over a species' geographical range must be well understood and targeted to plan effective control measures based on the population dynamics of the local Anopheles species.

  4. Inducible Clindamycin Resistance in Staphylococcus Species

    International Nuclear Information System (INIS)

    Afridi, F. I.; Zeb, M.; Farooqi, B. J.; Murtaza, G.; Hussain, A.

    2014-01-01

    Objective: To determine the frequency of inducible clindamycin resistance in clinical isolates of Staphylococcus species by phenotypic D-test. Study Design: Observational study. Place and Duration of Study: Ziauddin University Hospital, Karachi, from July to December 2011. Methodology: Consecutive clinical isolates of Staphylococcus species were collected and identified by conventional microbiological techniques. Antimicrobial susceptibility testing and inducible clindamycin resistance was carried out by performing D-test using CLSI criteria. Methicillin resistance was detected by using Cefoxitin disk as a surrogate marker. Statistical analysis was performed by SPSS version-17. Results: A total of 667 clinical isolates of Staphylococcus species were obtained during the study period. In these isolates, 177 (26.5%) were Staphylococcus aureus, and 490 (73.5%) were coagulase negative Staphylococci. The total frequency of inducible clindamycin resistance among isolates of Staphylococcus species was 120/667 (18%). Frequency of inducible clindamycin resistance among coagulase negative Staphylococci group and Staphylococcus aureus group were 18.57% and 16.38% respectively. Median age of patients in D-test positive group was 19.5 (1 - 54) years. Conclusion: The frequency of inducible clindamycin resistance among Staphylococcus species may differ in different hospital setup. Clinical microbiology laboratories should implement testing simple and effective D-test on all Staphylococcus species. D-test positive isolates should be reported clindamycin resistant to decrease treatment failure. (author)

  5. Chilli anthracnose disease caused by Colletotrichum species.

    Science.gov (United States)

    Than, Po Po; Prihastuti, Haryudian; Phoulivong, Sitthisack; Taylor, Paul W J; Hyde, Kevin D

    2008-10-01

    Anthracnose disease is one of the major economic constraints to chilli production worldwide, especially in tropical and subtropical regions. Accurate taxonomic information is necessary for effective disease control management. In the Colletotrichum patho-system, different Colletotrichum species can be associated with anthracnose of the same host. Little information is known concerning the interactions of the species associated with the chilli anthracnose although several Colletotrichum species have been reported as causal agents of chilli anthracnose disease worldwide. The ambiguous taxonomic status of Colletotrichum species has resulted in inaccurate identification which may cause practical problems in plant breeding and disease management. Although the management and control of anthracnose disease are still being extensively researched, commercial cultivars of Capsicum annuum that are resistant to the pathogens that cause chilli anthracnose have not yet been developed. This paper reviews the causal agents of chilli anthracnose, the disease cycle, conventional methods in identification of the pathogen and molecular approaches that have been used for the identification of Colletotrichum species. Pathogenetic variation and population structure of the causal agents of chilli anthracnose along with the current taxonomic status of Colletotrichum species are discussed. Future developments leading to the disease management strategies are suggested.

  6. Phytochemistry and Pharmacology of Berberis Species

    Science.gov (United States)

    Mokhber-Dezfuli, Najmeh; Saeidnia, Soodabeh; Gohari, Ahmad Reza; Kurepaz-Mahmoodabadi, Mahdieh

    2014-01-01

    The genus Berberis (Berberidaceae) includes about 500 species worldwide, some of which are widely cultivated in the north-eastern regions of Iran. This genus consists of spiny deciduous evergreen shrubs, characterized by yellow wood and flowers. The cultivation of seedless barberry in South Khorasan goes back to two hundred years ago. Medicinal properties for all parts of these plants have been reported, including: Antimicrobial, antiemetic, antipyretic, antioxidant, anti-inflammatory, anti-arrhythmic, sedative, anti-cholinergic, cholagogic, anti-leishmaniasis, and anti-malaria. The main compounds found in various species of Berberis, are berberine and berbamine. Phytochemical analysis of various species of this genus revealed the presence of alkaloids, tannins, phenolic compounds, sterols and triterpenes. Although there are some review articles on Berberis vulgaris (as the most applied species), there is no review on the phytochemical and pharmacological activities of other well-known species of the genus Berberis. For this reason, the present review mainly focused on the diverse secondary metabolites of various species of this genus and the considerable pharmacological and biological activities together with a concise story of the botany and cultivation. PMID:24600191

  7. Rare species are valued big time.

    Directory of Open Access Journals (Sweden)

    Elena Angulo

    Full Text Available BACKGROUND: It has recently been postulated that the value humans place on rarity could cause the extinction of rare species. This is because people are willing to pay the high costs of exploiting the last individuals. Many hobbies, such as ecotourism or the keeping of exotic pets may cause this effect--known as the anthropogenic Allee effect. However, the entire theory relies on the insofar undemonstrated assumption that people do value rarity. METHODOLOGY/PRINCIPAL FINDINGS: In order to quantify how much people valued rare species relative to common ones, we created online slideshows of photographs of either rare or common species on an Internet web site. The slideshow with photographs of rare species attracted more visitors, and visitors spent, in general, more time waiting to view it. CONCLUSIONS/SIGNIFICANCE: We provide evidence that people value rare more than common species. As we did not target consumers of a specific market, this finding suggests that the anthropogenic Allee effect is likely be driven by a large part of the population. Given the substantial participation in our online experiment, we highlight the potential of the world wide web resource as a tool for conservation action. However, the evidence presented here that the general public value rare species, combined with the assumption that anthropogenic Allee effect is operating, implies that conservationists should be prudent when using rarity to promote conservation.

  8. Assessing species saturation: conceptual and methodological challenges.

    Science.gov (United States)

    Olivares, Ingrid; Karger, Dirk N; Kessler, Michael

    2018-05-07

    Is there a maximum number of species that can coexist? Intuitively, we assume an upper limit to the number of species in a given assemblage, or that a lineage can produce, but defining and testing this limit has proven problematic. Herein, we first outline seven general challenges of studies on species saturation, most of which are independent of the actual method used to assess saturation. Among these are the challenge of defining saturation conceptually and operationally, the importance of setting an appropriate referential system, and the need to discriminate among patterns, processes and mechanisms. Second, we list and discuss the methodological approaches that have been used to study species saturation. These approaches vary in time and spatial scales, and in the variables and assumptions needed to assess saturation. We argue that assessing species saturation is possible, but that many studies conducted to date have conceptual and methodological flaws that prevent us from currently attaining a good idea of the occurrence of species saturation. © 2018 Cambridge Philosophical Society.

  9. Reptilian reovirus: a new fusogenic orthoreovirus species

    International Nuclear Information System (INIS)

    Duncan, Roy.; Corcoran, Jennifer; Shou Jingyun; Stoltz, Don

    2004-01-01

    The fusogenic subgroup of orthoreoviruses contains most of the few known examples of non-enveloped viruses capable of inducing syncytium formation. The only unclassified orthoreoviruses at the species level represent several fusogenic reptilian isolates. To clarify the relationship of reptilian reoviruses (RRV) to the existing fusogenic and nonfusogenic orthoreovirus species, we undertook a characterization of a python reovirus isolate. Biochemical, biophysical, and biological analyses confirmed the designation of this reptilian reovirus (RRV) isolate as an unclassified fusogenic orthoreovirus. Sequence analysis revealed that the RRV S1 and S3 genome segments contain a novel conserved 5'-terminal sequence not found in other orthoreovirus species. In addition, the gene arrangement and the coding potential of the bicistronic RRV S1 genome segment differ from that of established orthoreovirus species, encoding a predicted homologue of the reovirus cell attachment protein and a unique 125 residue p14 protein. The RRV S3 genome segment encodes a homologue of the reovirus sigma-class major outer capsid protein, although it is highly diverged from that of other orthoreovirus species (amino acid identities of only 16-25%). Based on sequence analysis, biological properties, and phylogenetic analysis, we propose this python reovirus be designated as the prototype strain of a fifth species of orthoreoviruses, the reptilian reoviruses

  10. Diversity of cuticular wax among Salix species and Populus species hybrids.

    Science.gov (United States)

    Cameron, Kimberly D; Teece, Mark A; Bevilacqua, Eddie; Smart, Lawrence B

    2002-08-01

    The leaf cuticular waxes of three Salix species and two Populus species hybrids, selected for their ability to produce high amounts of biomass, were characterized. Samples were extracted in CH(2)Cl(2) three times over the growing season. Low kV SEM was utilized to observe differences in the ultrastructure of leaf surfaces from each clone. Homologous series of wax components were classified into organic groups, and the variation in wax components due to clone, sample time, and their interaction was identified. All Salix species and Populus species hybrids showed differences in total wax load at each sampling period, whereas the pattern of wax deposition over time differed only between the Salix species. A strong positive relationship was identified between the entire homologous series of alcohols and total wax load in all clones. Similarly strong relationships were observed between fatty acids and total wax load as well as fatty acids and alcohols in two Salix species and one Populus species hybrid. One Salix species, S. dasyclados, also displayed a strong positive relationship between alcohols and alkanes. These data indicate that species grown under the same environmental conditions produce measurably different cuticular waxes and that regulation of wax production appears to be different in each species. The important roles cuticular waxes play in drought tolerance, pest, and pathogen resistance, as well as the ease of wax extraction and analysis, strongly suggest that the characteristics of the cuticular wax may prove to be useful selectable traits in a breeding program.

  11. Dietary effects of four phytoecdysteroids on growth and development of the Indian meal moth, Plodia interpunctella.

    Science.gov (United States)

    Rharrabe, Kacem; Sayan, Fouad; Lafont, René

    2010-01-01

    Using pure phytoecdysteroids isolated from Ajuga iva (L.) Schreber (Lamiales: Lamiaceae) and Silene nutans L. (Caryophyllales: Caryophyllaceae), plants known for their high ecdysteroid content, a study was carried out on the effects of ingestion of four different phytoecdysteroids (20-hydroxyecdysone, polypodine B, ponasterone A and makisterone A) on the growth and development of the Indian meal moth, Plodia interpunctella Hübner (Lepidoptera: Pyralidae) larvae when added at a concentration of 200 ppm in their diet. The experiments clearly showed the susceptibility of P. interpunctella to phytoecdysteroid ingestion. The toxicity of phytoecdysteroids manifested itself by a decrease in larval weight, induction of cannibalism and an increase of mortality, together with disruption of development. The severity of the phytoecdysteroid effect on P. interpunctella depended on the structure of the molecule. The results demonstrate that the minimal structural differences existing between these four phytoecdysteroids significantly affected their toxicity toward P. interpunctella. Makisterone A was the most toxic of the four compounds towards P. interpunctella larvae. In conclusion, phytoecdysteroids ingestion evokes disruptive growth effects on P. interpunctella. This work supports a role for phytoecdysteroids in plant defence against phytophagous insects.

  12. ЧИСЛА ХРОМОСОМ НЕКОТОРЫХ ВИДОВ ДВУДОЛЬНЫХ РАСТЕНИЙ ЮЖНОЙ СИБИРИ И КАЗАХСТАНА

    Directory of Open Access Journals (Sweden)

    T. V. An’kova

    2015-04-01

    Full Text Available Приведены числа хромосом (2n для девяти видов семейств Asteraceae, Caryophyllaceae, Fabaceae, Rosaceae и Scrophulariaceae. Впервые определены числа хромосом Silene cretacea (2n=20 и Oxytropis stenofoliola (2n=48. Впервые для Казахстана и Южной Сибири (Западный Саян, Новосибирская область определены числа хромосом у Jurinea arachnoidea, Tragopogon ruber, Astragalus brachylobus, A. cicer, A. danicus, Verbascum phoeniceum.

  13. Reconciliation with non-binary species trees.

    Science.gov (United States)

    Vernot, Benjamin; Stolzer, Maureen; Goldman, Aiton; Durand, Dannie

    2008-10-01

    Reconciliation extracts information from the topological incongruence between gene and species trees to infer duplications and losses in the history of a gene family. The inferred duplication-loss histories provide valuable information for a broad range of biological applications, including ortholog identification, estimating gene duplication times, and rooting and correcting gene trees. While reconciliation for binary trees is a tractable and well studied problem, there are no algorithms for reconciliation with non-binary species trees. Yet a striking proportion of species trees are non-binary. For example, 64% of branch points in the NCBI taxonomy have three or more children. When applied to non-binary species trees, current algorithms overestimate the number of duplications because they cannot distinguish between duplication and incomplete lineage sorting. We present the first algorithms for reconciling binary gene trees with non-binary species trees under a duplication-loss parsimony model. Our algorithms utilize an efficient mapping from gene to species trees to infer the minimum number of duplications in O(|V(G) | x (k(S) + h(S))) time, where |V(G)| is the number of nodes in the gene tree, h(S) is the height of the species tree and k(S) is the size of its largest polytomy. We present a dynamic programming algorithm which also minimizes the total number of losses. Although this algorithm is exponential in the size of the largest polytomy, it performs well in practice for polytomies with outdegree of 12 or less. We also present a heuristic which estimates the minimal number of losses in polynomial time. In empirical tests, this algorithm finds an optimal loss history 99% of the time. Our algorithms have been implemented in NOTUNG, a robust, production quality, tree-fitting program, which provides a graphical user interface for exploratory analysis and also supports automated, high-throughput analysis of large data sets.

  14. The status of Botryosphaeriaceae species infecting grapevines

    Directory of Open Access Journals (Sweden)

    Jose Ramón URBEZ-TORRES

    2011-12-01

    Full Text Available Normal 0 MicrosoftInternetExplorer4 Normal 0 MicrosoftInternetExplorer4 Species in the Botryosphaeriaceae have a cosmopolitan distribution, and occur on a wide range of annual and perennial hosts including grapevines. To date, morphological and taxonomic studies, as well as analyses of nucleotide sequences of multiple genes, have allowed the identification of at least 21 different species in the Botryosphaeriaceae occurring in grapevines worldwide. Grapevine disease symptoms caused by members of this family include leaf spots, fruit rots, shoot dieback, bud necrosis, vascular discoloration of the wood, and perennial cankers, and their current status as pathogens is reviewed. Additionally, the disease name Botryosphaeria dieback is proposed here to describe the different grapevine trunk disease symptoms caused by species of Botryosphaeriaceae. Much has been written during the last decade about the association between species in the Botryosphaeriaceae and grapevine trunk diseases, which has contributed to a better understanding of the role that these fungal taxa play in grapevine diseases. Although virulence has been shown to vary between species and isolates of the same species in different countries, these fungi have become well-recognized as important grapevine pathogens worldwide. Latest and novel findings from studies conducted in different countries, on disease etiology and species distribution, epidemiology and biology are discussed. Much progress has been achieved in the development and implementation of novel diagnostic and detection techniques.Vineyard sanitation techniques, as well as chemical, biological, and cultural control strategies available at the present time to reduce the infection caused by botryosphaeriaceous fungi, are presented in this review. 

  15. New species of Auritella (Inocybaceae) from Cameroon, with a worldwide key to the known species.

    Science.gov (United States)

    Matheny, P Brandon; Henkel, Terry W; Séné, Olivier; Korotkin, Hailee B; Dentinger, Bryn T M; Aime, M Catherine

    2017-12-01

    Two new species in the genus Auritella ( Inocybaceae ) are described as new from tropical rainforest in Cameroon. Descriptions, photographs, line drawings, and a worldwide taxonomic key to the described species of Auritella are presented. Phylogenetic analysis of 28S rDNA and rpb2 nucleotide sequence data suggests at least five phylogenetic species that can be ascribed to Auritella occur in the region comprising Cameroon and Gabon and constitute a strongly supported monophyletic subgroup within the genus. Phylogenetic analysis of ITS data supports the conspecificity of numerous collections attributed to the two new species as well as the monophyly of Australian species of Auritella . This work raises the known number of described species of Auritella to thirteen worldwide, four of which occur in tropical Africa, one in tropical India, and eight in temperate and tropical regions of Australia. This is the first study to confirm an ectomycorrhizal status of Auritella using molecular data.

  16. Molluscan indicator species and their potential use in ecological status assessment using species distribution modeling.

    Science.gov (United States)

    Moraitis, Manos L; Tsikopoulou, Irini; Geropoulos, Antonios; Dimitriou, Panagiotis D; Papageorgiou, Nafsika; Giannoulaki, Marianna; Valavanis, Vasilis D; Karakassis, Ioannis

    2018-05-24

    Marine habitat assessment using indicator species through Species Distribution Modeling (SDM) was investigated. The bivalves: Corbula gibba and Flexopecten hyalinus were the indicator species characterizing disturbed and undisturbed areas respectively in terms of chlorophyll a concentration in Greece. The habitat suitability maps of these species reflected the overall ecological status of the area. The C. gibba model successfully predicted the occurrence of this species in areas with increased physical disturbance driven by chlorophyll a concentration, whereas the habitat map for F. hyalinus showed an increased probability of occurrence in chlorophyll-poor areas, affected mainly by salinity. We advocate the use of C. gibba as a proxy for eutrophication and the incorporation of this species in monitoring studies through SDM methods. For the Mediterranean Sea we suggest the use of F. hyalinus in SDM as an indicator of environmental stability and a possible forecasting tool for salinity fluctuations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Reproductive Impacts of Endocrine-Disrupting Chemicals on Wildlife Species: Implications for Conservation of Endangered Species.

    Science.gov (United States)

    Tubbs, Christopher W; McDonough, Caitlin E

    2018-02-15

    Wildlife have proven valuable to our understanding of the potential effects of endocrine-disrupting chemicals (EDCs) on human health by contributing considerably to our understanding of the mechanisms and consequences of EDC exposure. But the threats EDCs present to populations of wildlife species themselves are significant, particularly for endangered species whose existence is vulnerable to any reproductive perturbation. However, few studies address the threats EDCs pose to endangered species owing to challenges associated with their study. Here, we highlight those barriers and review the available literature concerning EDC effects on endangered species. Drawing from other investigations into nonthreatened wildlife species, we highlight opportunities for new approaches to advance our understanding and potentially mitigate the effects of EDCs on endangered species to enhance their fertility.

  18. Biological review of 82 species of coral petitioned to be included in the Endangered Species Act

    Science.gov (United States)

    Brainard, Russell E.; Birkeland, Charles; Eakin, C. Mark; McElhany, Paul; Miller, Margaret W.; Patterson, Matt; Piniak, G.A.

    2011-01-01

    list 83 coral species as threatened or endangered under the U.S. Endangered Species Act. The petition was based on a predicted decline in available habitat for the species, citing anthropogenic climate change and ocean acidification as the lead factors among the various stressors responsible for the potential decline. The NMFS identified 82 of the corals as candidate species, finding that the petition provided substantive information for a potential listing of these species. The NMFS established a Biological Review Team (BRT) to prepare this Status Review Report that examines the status of these 82 candidate coral species and evaluates extinction risk for each of them. This document makes no recommendations for listing, as that is a separate evaluation to be conducted by the NMFS.

  19. Proactive Conservation Program: Species of Concern :: NOAA Fisheries

    Science.gov (United States)

    Invertebrates & Plants Species of Concern Threatened & Endangered Health & Stranding Marine Mammals : Species of Concern Species of Concern List | Grants and Technical Resources/Links bluefin tuna Bluefin Tuna (Thunnus thynnus) Photo: NOAA Species of Concern are those species about which we have some

  20. Effects of habitat structure and altitudinal gradients on avian species ...

    African Journals Online (AJOL)

    ... effect on bird species diversity. Bird species diversity increased with increase in tree height. A significant decline in bird species diversity with increased number of trees and canopy cover was noted. This result probably suggests an accumulation of forest edge species and generalist species in the less forested habitat.

  1. Delineating probabilistic species pools in ecology and biogeography

    OpenAIRE

    Karger, Dirk Nikolaus; Cord, Anna F; Kessler, Michael; Kreft, Holger; Kühn, Ingolf; Pompe, Sven; Sandel, Brody; Sarmento Cabral, Juliano; Smith, Adam B; Svenning, Jens-Christian; Tuomisto, Hanna; Weigelt, Patrick; Wesche, Karsten

    2016-01-01

    Aim To provide a mechanistic and probabilistic framework for defining the species pool based on species-specific probabilities of dispersal, environmental suitability and biotic interactions within a specific temporal extent, and to show how probabilistic species pools can help disentangle the geographical structure of different community assembly processes. Innovation Probabilistic species pools provide an improved species pool definition based on probabilities in conjuncti...

  2. Two new species of the Phanaeus endymion species group (Coleoptera, Scarabaeidae, Scarabaeinae).

    Science.gov (United States)

    Moctezuma, Victor; Sánchez-Huerta, José Luis; Halffter, Gonzalo

    2017-01-01

    Phanaeus bravoensis sp. n. is described from the coniferous-oak forests in the state of Guerrero, and P. huichol sp. n. from coniferous-oak forests and cloud forests in Jalisco and Nayarit. The new species are closely related to P. halffterorum and P. zoque respectively. Morphological trait combination, geographic distribution, and trophic habits show important differences among the studied species. A distribution map and an updated key to separate the species are included.

  3. Discordance between morphological and molecular species boundaries among Caribbean species of the reef sponge Callyspongia

    OpenAIRE

    DeBiasse, Melissa B; Hellberg, Michael E

    2015-01-01

    Sponges are among the most species-rich and ecologically important taxa on coral reefs, yet documenting their diversity is difficult due to the simplicity and plasticity of their morphological characters. Genetic attempts to identify species are hampered by the slow rate of mitochondrial sequence evolution characteristic of sponges and some other basal metazoans. Here we determine species boundaries of the Caribbean coral reef sponge genus Callyspongia using a multilocus, model-based approach...

  4. Indicator species of essential forest tree species in the Burdur district.

    Science.gov (United States)

    Negiz, Mehmet Güvenç; Eser, Yunus; Kuzugüdenll, Emre; Izkan, Kürşad

    2015-01-01

    The forests of Burdur district for long have been subjected to over grazing and individual selection. As a result of this, majority of the forest areas in the district were degraded. In the district, afforestation efforts included majority of forestry implementations. It is well known that selecting suitable species plays an important role for achieving afforestation efforts. In this context, knowing the indicator species among the target species would be used in afforestation efforts, studies on the interrelationships between environmental factors and target species distribution is vital for selecting suitable species for a given area. In this study, Anatolian Black pine (Pinus nigra), Red pine (Pinus brutia), Crimean juniper (Juniperus excelsa) and Taurus cedar (Cedrus libani), essential tree species, were considered as target species. The data taken from 100 sample plots in Burdur district was used. Interspecific correlation analysis was performed to determine the positive and negative indicator species among each of the target species. As a result of ICA, 2 positive (Berberis crataegina, Juniperus oxycedrus), 2 negative (Phillyrea latifolia, Quercus coccifera) for Crimean Juniper, I positive (Juniperus oxycedrus), 3 negative (Onopordium acanthium, Fraxinus ornus, Phillyrea latifolia) for Anatolian black pine, 3 positive (Paliurus spina-christi, Quercus coccifer, Crataegus orientalis), 2 negative (Berberis crataegina, Astragalus nanus) for Red pine and 3 positive (Berberis crataegina, Rhamnus oleoides, Astragalus prusianus) 2 negative (Paliurus spina-christi, Quercus cerris) for Taurus cedarwere defined as indicator plant species. In this way, practical information was obtained for selecting the most suitable species, among the target species, for afforestation efforts in Burdur district.

  5. Evaluating Hypotheses of Plant Species Invasions on Mediterranean Islands: Inverse Patterns between Alien and Endemic Species

    Directory of Open Access Journals (Sweden)

    Alexander Bjarnason

    2017-08-01

    Full Text Available Invasive alien species cause major changes to ecosystem functioning and patterns of biodiversity, and the main factors involved in invasion success remain contested. Using the Mediterranean island of Crete, Greece as a case study, we suggest a framework for analyzing spatial data of alien species distributions, based on environmental predictors, aiming to gain an understanding of their spatial patterns and spread. Mediterranean islands are under strong ecological pressure from invading species due to their restricted size and increased human impact. Four hypotheses of invasibility, the “propagule pressure hypothesis” (H1, “biotic resistance hypothesis vs. acceptance hypothesis” (H2, “disturbance-mediated hypothesis” (H3, and “environmental heterogeneity hypothesis” (H4 were tested. Using data from alien, native, and endemic vascular plant species, the propagule pressure, biotic resistance vs. acceptance, disturbance-mediated, and environmental heterogeneity hypotheses were tested with Generalized Additive Modeling (GAM of 39 models. Based on model selection, the optimal model includes the positive covariates of native species richness, the negative covariates of endemic species richness, and land area. Variance partitioning between the four hypotheses indicated that the biotic resistance vs. acceptance hypothesis explained the vast majority of the total variance. These results show that areas of high species richness have greater invasibility and support the acceptance hypothesis and “rich-get-richer” distribution of alien species. The negative correlation between alien and endemic species appears to be predominantly driven by altitude, with fewer alien and more endemic species at greater altitudes, and habitat richness. The negative relationship between alien and endemic species richness provides potential for understanding patterns of endemic and alien species on islands, contributing to more effective conservation

  6. Two-species occupancy modeling accounting for species misidentification and nondetection

    Science.gov (United States)

    Chambert, Thierry; Grant, Evan H. Campbell; Miller, David A. W.; Nichols, James; Mulder, Kevin P.; Brand, Adrianne B,

    2018-01-01

    1. In occupancy studies, species misidentification can lead to false positive detections, which can cause severe estimator biases. Currently, all models that account for false positive errors only consider omnibus sources of false detections and are limited to single species occupancy. 2. However, false detections for a given species often occur because of the misidentification with another, closely-related species. To exploit this explicit source of false positive detection error, we develop a two-species occupancy model that accounts for misidentifications between two species of interest. As with other false positive models, identifiability is greatly improved by the availability of unambiguous detections at a subset of site-occasions. Here, we consider the case where some of the field observations can be confirmed using laboratory or other independent identification methods (“confirmatory data”). 3. We performed three simulation studies to (1) assess the model’s performance under various realistic scenarios, (2) investigate the influence of the proportion of confirmatory data on estimator accuracy, and (3) compare the performance of this two-species model with that of the single-species false positive model. The model shows good performance under all scenarios, even when only small proportions of detections are confirmed (e.g., 5%). It also clearly outperforms the single-species model.

  7. Bias correction in species distribution models: pooling survey and collection data for multiple species.

    Science.gov (United States)

    Fithian, William; Elith, Jane; Hastie, Trevor; Keith, David A

    2015-04-01

    Presence-only records may provide data on the distributions of rare species, but commonly suffer from large, unknown biases due to their typically haphazard collection schemes. Presence-absence or count data collected in systematic, planned surveys are more reliable but typically less abundant.We proposed a probabilistic model to allow for joint analysis of presence-only and survey data to exploit their complementary strengths. Our method pools presence-only and presence-absence data for many species and maximizes a joint likelihood, simultaneously estimating and adjusting for the sampling bias affecting the presence-only data. By assuming that the sampling bias is the same for all species, we can borrow strength across species to efficiently estimate the bias and improve our inference from presence-only data.We evaluate our model's performance on data for 36 eucalypt species in south-eastern Australia. We find that presence-only records exhibit a strong sampling bias towards the coast and towards Sydney, the largest city. Our data-pooling technique substantially improves the out-of-sample predictive performance of our model when the amount of available presence-absence data for a given species is scarceIf we have only presence-only data and no presence-absence data for a given species, but both types of data for several other species that suffer from the same spatial sampling bias, then our method can obtain an unbiased estimate of the first species' geographic range.

  8. Seasonal species interactions minimize the impact of species turnover on the likelihood of community persistence.

    Science.gov (United States)

    Saavedra, Serguei; Rohr, Rudolf P; Fortuna, Miguel A; Selva, Nuria; Bascompte, Jordi

    2016-04-01

    Many of the observed species interactions embedded in ecological communities are not permanent, but are characterized by temporal changes that are observed along with abiotic and biotic variations. While work has been done describing and quantifying these changes, little is known about their consequences for species coexistence. Here, we investigate the extent to which changes of species composition impact the likelihood of persistence of the predator-prey community in the highly seasonal Białowieza Primeval Forest (northeast Poland), and the extent to which seasonal changes of species interactions (predator diet) modulate the expected impact. This likelihood is estimated extending recent developments on the study of structural stability in ecological communities. We find that the observed species turnover strongly varies the likelihood of community persistence between summer and winter. Importantly, we demonstrate that the observed seasonal interaction changes minimize the variation in the likelihood of persistence associated with species turnover across the year. We find that these community dynamics can be explained as the coupling of individual species to their environment by minimizing both the variation in persistence conditions and the interaction changes between seasons. Our results provide a homeostatic explanation for seasonal species interactions and suggest that monitoring the association of interactions changes with the level of variation in community dynamics can provide a good indicator of the response of species to environmental pressures.

  9. Socially-parasitic Myrmica species (Hymenoptera, Formicidae) of Himalaya, with the description of a new species.

    Science.gov (United States)

    Bharti, Himender; Radchenko, Alexander; Sasi, Sishal

    2016-01-01

    A new socially-parasitic species, Myrmica latra sp. n. is described based on a queen and male from Indian Himalaya. Its queen differs from other species by the distinctly narrower petiole and postpetiole, blunt and non-divergent propodeal spines, and a darker body colour. The taxonomic position of the three known Himalayan socially-parasitic Myrmica species is discussed, and Myrmica ereptrix Bolton 1988 is transferred to the smythiesii species-group. It is supposed that Myrmica nefaria Bharti 2012 is a temporary social parasite, but Myrmica ereptrix and Myrmica latra sp. n. are permanent social parasites, and a key for their identification is provided.

  10. Onychiurid species from Wanda Mountains in China, with descriptions of two new species (Collembola, Onychiuridae)

    Science.gov (United States)

    Sun, Xin; Wu, Donghui

    2014-01-01

    Abstract A checklist of onychiurid species from the Wanda Mountains in China is presented. Eighteen species belonging to twelve genera have been found, including two new species. Bionychiurus qinglongensis sp. n. can be easily distinguished from other known species of the genus by the absence of pseudocelli on Th. I tergum and fewer number of vesicles in postantennal organ. Onychiurus heilongjiangensis sp. n. is diagnosed by pseudocellar formulae as 32/133/33352 dorsally and 3/011/31120 ventrally, parapseudocellar formula as 0/000/111001+1m, ratio of anal spine/unguis as 0.6, unguiculus without inner basal lamella, and male ventral organ absent. PMID:25147452

  11. Reconciliation of Gene and Species Trees

    Directory of Open Access Journals (Sweden)

    L. Y. Rusin

    2014-01-01

    Full Text Available The first part of the paper briefly overviews the problem of gene and species trees reconciliation with the focus on defining and algorithmic construction of the evolutionary scenario. Basic ideas are discussed for the aspects of mapping definitions, costs of the mapping and evolutionary scenario, imposing time scales on a scenario, incorporating horizontal gene transfers, binarization and reconciliation of polytomous trees, and construction of species trees and scenarios. The review does not intend to cover the vast diversity of literature published on these subjects. Instead, the authors strived to overview the problem of the evolutionary scenario as a central concept in many areas of evolutionary research. The second part provides detailed mathematical proofs for the solutions of two problems: (i inferring a gene evolution along a species tree accounting for various types of evolutionary events and (ii trees reconciliation into a single species tree when only gene duplications and losses are allowed. All proposed algorithms have a cubic time complexity and are mathematically proved to find exact solutions. Solving algorithms for problem (ii can be naturally extended to incorporate horizontal transfers, other evolutionary events, and time scales on the species tree.

  12. SPECIES DIVERSITY AND STABILITY OF BIRD COMMUNITIES

    Directory of Open Access Journals (Sweden)

    Matsyura M.V.

    2011-12-01

    Full Text Available When comparing the suggested stability indicators, we obtained statistically significant correlations for indicators of annual stability of species and total number and standard deviation of the logarithm of the number. Annual Stability Index can be applied with a high degree of reliability as a characteristic of the averaged structure of the community and its pyramid of abundances. The results of correlation analysis confirm our assumptions about the correlation between stability over the years and indices of species diversity and relative uniformity.The final task of the study was to create a mathematical model of stability, where the independent variables are the indices of species diversity. The calculation of these indices allows forecasting birds’ community stability. According to the result of multiple regression for the indicators of diversity and stability of the breeding birds’ community highest correlation coefficients were obtained fro Shannon index and Simpson's dominance Index.Community stability could be determined by its overall species diversity. When considering the stability of community its diversity should be considered as a combination of uniformity of their total number and number of species. The most suitable predictors for the community stability were the nonparametric index of dominance and information-statistical indices, since they considered simultaneously evenness and richness. The community stability is subject of the complexity of its internal communications pattern.

  13. Diversity in protein glycosylation among insect species.

    Directory of Open Access Journals (Sweden)

    Gianni Vandenborre

    Full Text Available BACKGROUND: A very common protein modification in multicellular organisms is protein glycosylation or the addition of carbohydrate structures to the peptide backbone. Although the Class of the Insecta is the largest animal taxon on Earth, almost all information concerning glycosylation in insects is derived from studies with only one species, namely the fruit fly Drosophila melanogaster. METHODOLOGY/PRINCIPAL FINDINGS: In this report, the differences in glycoproteomes between insects belonging to several economically important insect orders were studied. Using GNA (Galanthus nivalis agglutinin affinity chromatography, different sets of glycoproteins with mannosyl-containing glycan structures were purified from the flour beetle (Tribolium castaneum, the silkworm (Bombyx mori, the honeybee (Apis mellifera, the fruit fly (D. melanogaster and the pea aphid (Acyrthosiphon pisum. To identify and characterize the purified glycoproteins, LC-MS/MS analysis was performed. For all insect species, it was demonstrated that glycoproteins were related to a broad range of biological processes and molecular functions. Moreover, the majority of glycoproteins retained on the GNA column were unique to one particular insect species and only a few glycoproteins were present in the five different glycoprotein sets. Furthermore, these data support the hypothesis that insect glycoproteins can be decorated with mannosylated O-glycans. CONCLUSIONS/SIGNIFICANCE: The results presented here demonstrate that oligomannose N-glycosylation events are highly specific depending on the insect species. In addition, we also demonstrated that protein O-mannosylation in insect species may occur more frequently than currently believed.

  14. Pain, Cannabis Species, and Cannabis Use Disorders

    Science.gov (United States)

    Cohen, Nicole L.; Heinz, Adrienne J.; Ilgen, Mark; Bonn-Miller, Marcel O.

    2016-01-01

    Objective: The purpose of this study was to examine whether individuals who used medical cannabis for chronic pain were at increased risk for cannabis use problems compared with individuals who used medical cannabis for other reasons (e.g., anxiety, insomnia, and muscle spasms). An additional aim was to determine whether individuals who used cannabis for chronic pain, as well as those who reported greater within-group pain levels, demonstrated a species preference (i.e., sativa, indica, hybrids) and the extent to which species preference was associated with cannabis use problems. Method: Participants were 163 medical cannabis users (77% male), recruited from a medical marijuana dispensary in California, who completed assessments of medical cannabis use motives, history, preferences (species type), and problems, as well as current pain level. Results: Individuals who used cannabis to manage chronic pain experienced fewer cannabis use problems than those who did not use it for pain; among those who used it for pain, the average pain level in the past week was not associated with cannabis use problems. Furthermore, individuals who used cannabis for chronic pain were more likely to use indica over sativa. Preference for indica was associated with fewer cannabis use problems than preference for hybrid species. Conclusions: Individuals who use cannabis to manage chronic pain may be at a lower risk for cannabis use problems, relative to individuals who use it for other indications, potentially as a function of their species preference. PMID:27172585

  15. Bracken: estimating species abundance in metagenomics data

    Directory of Open Access Journals (Sweden)

    Jennifer Lu

    2017-01-01

    Full Text Available Metagenomic experiments attempt to characterize microbial communities using high-throughput DNA sequencing. Identification of the microorganisms in a sample provides information about the genetic profile, population structure, and role of microorganisms within an environment. Until recently, most metagenomics studies focused on high-level characterization at the level of phyla, or alternatively sequenced the 16S ribosomal RNA gene that is present in bacterial species. As the cost of sequencing has fallen, though, metagenomics experiments have increasingly used unbiased shotgun sequencing to capture all the organisms in a sample. This approach requires a method for estimating abundance directly from the raw read data. Here we describe a fast, accurate new method that computes the abundance at the species level using the reads collected in a metagenomics experiment. Bracken (Bayesian Reestimation of Abundance after Classification with KrakEN uses the taxonomic assignments made by Kraken, a very fast read-level classifier, along with information about the genomes themselves to estimate abundance at the species level, the genus level, or above. We demonstrate that Bracken can produce accurate species- and genus-level abundance estimates even when a sample contains multiple near-identical species.

  16. Atomic collisions research with excited atomic species

    International Nuclear Information System (INIS)

    Hoogerland, M.D.; Gulley, R.J.; Colla, M.; Lu, W.; Milic, D.; Baldwin, K.G.H.; Buckman, S.J.

    1999-01-01

    Measurements and calculations of fundamental atomic collision and spectroscopic properties such as collision cross sections, reaction rates, transition probabilities etc. underpin the understanding and operation of many plasma and gas-discharge-based devices and phenomena, for example plasma processing and deposition. In almost all cases the complex series of reactions which sustains the discharge or plasma, or produces the reactive species of interest, has a precursor electron impact excitation, attachment, dissociation or ionisation event. These processes have been extensively studied in a wide range of atomic and molecular species and an impressive data base of collision cross sections and reaction rates now exists. However, most of these measurements are for collisions with stable atomic or molecular species which are initially in their ground electronic state. Relatively little information is available for scattering from excited states or for scattering from unstable molecular radicals. Examples of such species would be metastable excited rare gases, which are often used as buffer gases, or CF 2 radicals formed by electron impact dissociation in a CF 4 plasma processing discharge. We are interested in developing experimental techniques which will enable the quantitative study of such exotic atomic and molecular species. In this talk I would like to outline one such facility which is being used for studies of collisions with metastable He(2 3 S) atoms

  17. Exploring similarities among many species distributions

    Science.gov (United States)

    Simmerman, Scott; Wang, Jingyuan; Osborne, James; Shook, Kimberly; Huang, Jian; Godsoe, William; Simons, Theodore R.

    2012-01-01

    Collecting species presence data and then building models to predict species distribution has been long practiced in the field of ecology for the purpose of improving our understanding of species relationships with each other and with the environment. Due to limitations of computing power as well as limited means of using modeling software on HPC facilities, past species distribution studies have been unable to fully explore diverse data sets. We build a system that can, for the first time to our knowledge, leverage HPC to support effective exploration of species similarities in distribution as well as their dependencies on common environmental conditions. Our system can also compute and reveal uncertainties in the modeling results enabling domain experts to make informed judgments about the data. Our work was motivated by and centered around data collection efforts within the Great Smoky Mountains National Park that date back to the 1940s. Our findings present new research opportunities in ecology and produce actionable field-work items for biodiversity management personnel to include in their planning of daily management activities.

  18. Species richness, area and climate correlates

    DEFF Research Database (Denmark)

    Nogues, David Bravo; Bastos Araujo, Miguel

    2006-01-01

    affects: (1) the selection of climate variables entering a species richness model; and (2) the accuracy of models in predicting species richness in unsampled grid cells. Location Western Europe. Methods Models are developed for European plant, breeding bird, mammal and herptile species richness using...... seven climate variables. Generalized additive models are used to relate species richness, climate and area. Results We found that variation in the grid cell area was large (50 × 50 km: 8-3311 km2; 220 × 220: 193-55,100 km2), but this did not affect the selection of variables in the models. Similarly...... support the assumption that variation in near-equal area cells may be of second-order importance for models explaining or predicting species richness in relation to climate, although there is a possibility that drops in accuracy might increase with grid cell size. The results are, however, contingent...

  19. Pain, Cannabis Species, and Cannabis Use Disorders.

    Science.gov (United States)

    Cohen, Nicole L; Heinz, Adrienne J; Ilgen, Mark; Bonn-Miller, Marcel O

    2016-05-01

    The purpose of this study was to examine whether individuals who used medical cannabis for chronic pain were at increased risk for cannabis use problems compared with individuals who used medical cannabis for other reasons (e.g., anxiety, insomnia, and muscle spasms). An additional aim was to determine whether individuals who used cannabis for chronic pain, as well as those who reported greater within-group pain levels, demonstrated a species preference (i.e., sativa, indica, hybrids) and the extent to which species preference was associated with cannabis use problems. Participants were 163 medical cannabis users (77% male), recruited from a medical marijuana dispensary in California, who completed assessments of medical cannabis use motives, history, preferences (species type), and problems, as well as current pain level. Individuals who used cannabis to manage chronic pain experienced fewer cannabis use problems than those who did not use it for pain; among those who used it for pain, the average pain level in the past week was not associated with cannabis use problems. Furthermore, individuals who used cannabis for chronic pain were more likely to use indica over sativa. Preference for indica was associated with fewer cannabis use problems than preference for hybrid species. Individuals who use cannabis to manage chronic pain may be at a lower risk for cannabis use problems, relative to individuals who use it for other indications, potentially as a function of their species preference.

  20. 77 FR 30261 - Petition To List 83 Species of Coral as Threatened or Endangered Under the Endangered Species Act...

    Science.gov (United States)

    2012-05-22

    ... List 83 Species of Coral as Threatened or Endangered Under the Endangered Species Act (ESA) AGENCY... Diversity (CBD) to list 83 coral species as threatened or endangered under the Endangered Species Act (ESA... the U.S. Endangered Species Act (Status Review Report) and the draft Management Report for 82 Corals...

  1. Current understanding of multi-species biofilms

    DEFF Research Database (Denmark)

    Yang, Liang; Liu, Yang; Wu, Hong

    2011-01-01

    every year worldwide to deal with damage to equipment, contaminations of products, energy losses, and infections in human beings resulted from microbial biofilms. Microorganisms compete, cooperate, and communicate with each other in multi-species biofilms. Understanding the mechanisms of multi......Direct observation of a wide range of natural microorganisms has revealed the fact that the majority of microbes persist as surface-attached communities surrounded by matrix materials, called biofilms. Biofilms can be formed by a single bacterial strain. However, most natural biofilms are actually......-species biofilm formation will facilitate the development of methods for combating bacterial biofilms in clinical, environmental, industrial, and agricultural areas. The most recent advances in the understanding of multi-species biofilms are summarized and discussed in the review....

  2. Assessing species vulnerability to climate change

    Science.gov (United States)

    Pacifici, Michela; Foden, Wendy B.; Visconti, Piero; Watson, James E. M.; Butchart, Stuart H. M.; Kovacs, Kit M.; Scheffers, Brett R.; Hole, David G.; Martin, Tara G.; Akçakaya, H. Resit; Corlett, Richard T.; Huntley, Brian; Bickford, David; Carr, Jamie A.; Hoffmann, Ary A.; Midgley, Guy F.; Pearce-Kelly, Paul; Pearson, Richard G.; Williams, Stephen E.; Willis, Stephen G.; Young, Bruce; Rondinini, Carlo

    2015-03-01

    The effects of climate change on biodiversity are increasingly well documented, and many methods have been developed to assess species' vulnerability to climatic changes, both ongoing and projected in the coming decades. To minimize global biodiversity losses, conservationists need to identify those species that are likely to be most vulnerable to the impacts of climate change. In this Review, we summarize different currencies used for assessing species' climate change vulnerability. We describe three main approaches used to derive these currencies (correlative, mechanistic and trait-based), and their associated data requirements, spatial and temporal scales of application and modelling methods. We identify strengths and weaknesses of the approaches and highlight the sources of uncertainty inherent in each method that limit projection reliability. Finally, we provide guidance for conservation practitioners in selecting the most appropriate approach(es) for their planning needs and highlight priority areas for further assessments.

  3. Autofluorescence in eleocytes of some earthworm species.

    Directory of Open Access Journals (Sweden)

    Barbara Płytycz

    2006-04-01

    Full Text Available Immunocompetent cells of earthworms, coelomocytes, comprise adherent amoebocytes and granular eleocytes (chloragocytes. Both cell populations can be expelled via dorsal pores of adult earthworms by exposure to an electric current (4.5 V for 1 min. Analysis by phase contrast/fluorescence microscopy and flow cytometry demonstrated that eleocyte population of several species exhibits a strong autofluorescence. A high percentage (11-35% of autofluorescent eleocytes was recorded in Allolobophora chlorotica, Dendrodrilus rubidus, Eisenia fetida, and Octolasion sp. (O. cyaneum, O. tyrtaeum tyrtaeum and O. tyrtaeum lacteum. In contrast, autofluorescent coelomocytes were exceptionally scarce (less than 1% in representative Aporrectodea sp. (A. caliginosa and A. longa and Lumbricus sp. (L. castaneus, L. festivus, L. rubellus, L. terrestris. Thus, this paper for the first time describes profound intrinsic fluorescence of eleocytes in some--but not all--earthworm species. The function (if any and inter-species differences of the autofluorescent coelomocytes still remain elusive.

  4. The prairie dog as a keystone species

    Science.gov (United States)

    Kotliar, Natasha B.; Miller, Brian J.; Reading, Richard P.; Clark, Timothy W.; Hoogland, John L.

    2006-01-01

    The prairie dog has a pronounced impact on its grassland ecosystem (King 1955; Uresk and Bjugstad 1983; Miller et al. 1994; Society for Conservation Biology 1994; Wuerthner 1997; Johnsgard 2005). They maintain short vegetation by their grazing and by selective removal of tall plants and shrubs; provide shelter, foraging grounds, and nesting habitat for a diverse array of animals; serve as prey for many predators; and alter soil chemistry.Do these impacts mean that the prairie dog is a keystone species? To investigate, we first scrutinize the definition for a keystone species. We then document both vertebrates and invertebrates that associate with prairie dogs and their colony-sites. We examine ecosystem processes at colony-sites, and then assess whether the prairie dog is a legitimate keystone species. Finally, we explore the implications of keystone status for the conservation of prairie dogs.

  5. Forms and genesis of species abundance distributions

    Directory of Open Access Journals (Sweden)

    Evans O. Ochiaga

    2015-12-01

    Full Text Available Species abundance distribution (SAD is one of the most important metrics in community ecology. SAD curves take a hollow or hyperbolic shape in a histogram plot with many rare species and only a few common species. In general, the shape of SAD is largely log-normally distributed, although the mechanism behind this particular SAD shape still remains elusive. Here, we aim to review four major parametric forms of SAD and three contending mechanisms that could potentially explain this highly skewed form of SAD. The parametric forms reviewed here include log series, negative binomial, lognormal and geometric distributions. The mechanisms reviewed here include the maximum entropy theory of ecology, neutral theory and the theory of proportionate effect.

  6. Taxonomy of Penicillium citrinum and related species

    DEFF Research Database (Denmark)

    Houbraken, J.A.M.P.; Frisvad, Jens Christian; Samson, A.F.

    2010-01-01

    are related to P. citrinum, P. gorlenkoanum is revived, Penicillium hetheringtonii sp. nov. and Penicillium tropicoides sp. nov. are described here as new species, and the combination Penicillium tropicum is proposed. Penicillium hetheringtonii is closely related to P. citrinum and differs in having slightly......Penicillium citrinum and related species have been examined using a combination of partial beta-tubulin, calmodulin and ITS sequence data, extrolite patterns and phenotypic characters. It is concluded that seven species belong to the series Citrina. Penicillium sizovae and Penicillium steckii...... broader stipes, metulae in verticils of four or more and the production of an uncharacterized metabolite, tentatively named PR1-x. Penicillium tropicoides resembles P. tropicum, but differs in the slow maturation of the cleistothecia, slower growth at 30A degrees C and the production of isochromantoxins...

  7. WHITE BLISTER SPECIES (Albuginaceae ON WEEDS

    Directory of Open Access Journals (Sweden)

    Karolina Vrandečić

    2011-06-01

    Full Text Available The obligate fungi inside the family Albuginaceae are widespread world wide and cause white rust or white blister disease. Mycopopulation of weeds has been researched within the project „The role of weeds in epidemiology of row-crop diseases“. The aim of this research was to identify white blister species occurring on weeds in Eastern Croatia. Weed plants with disease symptoms characteristic for white blister species have been collected since 2001 on location Slavonia and Baranja country. Determination of white blister species was based on morphological characters of pathogen and the host. Wilsoniana bliti was determined on Amaranthus retroflexus and Amaranthus hybridus leaves. Capsella bursa pastoris is a host for Albugo candida. Ambrosia artemisiifolia is a host for Pustula sp. and Cirsium arvense was found to be host for Pustula spinulosa. Wilsoniana portulaceae was determined on Portulaca oleracea.

  8. Distribution of Vulpia species (Poaceae in Poland

    Directory of Open Access Journals (Sweden)

    Ludwik Frey

    2011-01-01

    Full Text Available The distribution of four species of the genus Vulpia [V. myuros (L. C.C. Gmel., V. bromoides (L. S.F. Gray, V. ciliata Dumort. and V. geniculata (L. Link] reported in Poland has been studied. Currently, V. myuros and especially V. bromoides are very rare species, and their greatest concentration can be found only in the Lower Silesia region. The number of their localities decreased after 1950 and it seems resonable to include both species in the "red list" of threatened plants in Poland: V. myuros in the EN category, V. bromoides in the CR category. V. ciliata and V. geniculata are very rare ephemerophytes and their localities not confirmed during ca 60 years are of historical interest only.

  9. Computational botany methods for automated species identification

    CERN Document Server

    Remagnino, Paolo; Wilkin, Paul; Cope, James; Kirkup, Don

    2017-01-01

    This book discusses innovative methods for mining information from images of plants, especially leaves, and highlights the diagnostic features that can be implemented in fully automatic systems for identifying plant species. Adopting a multidisciplinary approach, it explores the problem of plant species identification, covering both the concepts of taxonomy and morphology. It then provides an overview of morphometrics, including the historical background and the main steps in the morphometric analysis of leaves together with a number of applications. The core of the book focuses on novel diagnostic methods for plant species identification developed from a computer scientist’s perspective. It then concludes with a chapter on the characterization of botanists' visions, which highlights important cognitive aspects that can be implemented in a computer system to more accurately replicate the human expert’s fixation process. The book not only represents an authoritative guide to advanced computational tools fo...

  10. Capsular Polysaccharide Expression in Commensal Streptococcus Species

    DEFF Research Database (Denmark)

    Skov Sørensen, Uffe B; Yao, Kaihu; Yang, Yonghong

    2016-01-01

    Expression of a capsular polysaccharide is considered a hallmark of most invasive species of bacteria, including Streptococcus pneumoniae, in which the capsule is among the principal virulence factors and is the basis for successful vaccines. Consequently, it was previously assumed that capsule....... pneumoniae evolved by import of cps fragments from commensal Streptococcus species, resulting in a mosaic of genes of different origins. The demonstrated antigenic identity of at least eight of the numerous capsular polysaccharide structures expressed by commensal streptococci with recognized serotypes of S...... of Streptococcus pneumoniae and is the basis for successful vaccines against infections caused by this important pathogen. Contrasting with previous assumptions, this study showed that expression of capsular polysaccharides by the same genetic mechanisms is a general property of closely related species...

  11. Combinatorial Cis-regulation in Saccharomyces Species

    Directory of Open Access Journals (Sweden)

    Aaron T. Spivak

    2016-03-01

    Full Text Available Transcriptional control of gene expression requires interactions between the cis-regulatory elements (CREs controlling gene promoters. We developed a sensitive computational method to identify CRE combinations with conserved spacing that does not require genome alignments. When applied to seven sensu stricto and sensu lato Saccharomyces species, 80% of the predicted interactions displayed some evidence of combinatorial transcriptional behavior in several existing datasets including: (1 chromatin immunoprecipitation data for colocalization of transcription factors, (2 gene expression data for coexpression of predicted regulatory targets, and (3 gene ontology databases for common pathway membership of predicted regulatory targets. We tested several predicted CRE interactions with chromatin immunoprecipitation experiments in a wild-type strain and strains in which a predicted cofactor was deleted. Our experiments confirmed that transcription factor (TF occupancy at the promoters of the CRE combination target genes depends on the predicted cofactor while occupancy of other promoters is independent of the predicted cofactor. Our method has the additional advantage of identifying regulatory differences between species. By analyzing the S. cerevisiae and S. bayanus genomes, we identified differences in combinatorial cis-regulation between the species and showed that the predicted changes in gene regulation explain several of the species-specific differences seen in gene expression datasets. In some instances, the same CRE combinations appear to regulate genes involved in distinct biological processes in the two different species. The results of this research demonstrate that (1 combinatorial cis-regulation can be inferred by multi-genome analysis and (2 combinatorial cis-regulation can explain differences in gene expression between species.

  12. Nocardiopsis species: Incidence, ecological roles and adaptations.

    Science.gov (United States)

    Bennur, Tahsin; Kumar, Ameeta Ravi; Zinjarde, Smita; Javdekar, Vaishali

    2015-05-01

    Members of the genus Nocardiopsis are ecologically versatile and biotechnologically important. They produce a variety of bioactive compounds such as antimicrobial agents, anticancer substances, tumor inducers, toxins and immunomodulators. They also secrete novel extracellular enzymes such as amylases, chitinases, cellulases, β-glucanases, inulinases, xylanases and proteases. Nocardiopsis species are aerobic, Gram-positive, non-acid-fast, catalase-positive actinomycetes with nocardioform substrate mycelia and their aerial mycelia bear long chains of spores. Their DNA possesses high contents of guanine and cytosine. There is a marked variation in properties of the isolates obtained from different ecological niches and their products. An important feature of several species is their halophilic or halotolerant nature. They are associated with a variety of marine and terrestrial biological forms wherein they produce antibiotics and toxins that help their hosts in evading pathogens and predators. Two Nocardiopsis species, namely, N. dassonvillei and N. synnemataformans (among the thirty nine reported ones) are opportunistic human pathogens and cause mycetoma, suppurative infections and abscesses. Nocardiopsis species are present in some plants (as endophytes or surface microflora) and their rhizospheres. Here, they are reported to produce enzymes such as α-amylases and antifungal agents that are effective in warding-off plant pathogens. They are prevalent as free-living entities in terrestrial locales, indoor locations, marine ecosystems and hypersaline habitats on account of their salt-, alkali- and desiccation-resistant behavior. In such natural locations, Nocardiopsis species mainly help in recycling organic compounds. Survival under these diverse conditions is mediated by the production of extracellular enzymes, antibiotics, surfactants, and the accumulation of compatible solutes. The accommodative genomic features of Nocardiopsis species support their existence

  13. The Drosophila bipectinata species complex: degree of sterility and ...

    Indian Academy of Sciences (India)

    sophila bipectinata species complex, comprising four closely related species namely D. bipectinata, D. parabipectinata,. D. malerkotliana and D. ... vials with four males (two each from the respective parental species, to increase the probability ...

  14. Cryptic Sebastes norvegicus species in Greenland waters revealed by microsatellites

    DEFF Research Database (Denmark)

    Saha, Atal; Hauser, Lorenz; Hedeholm, Rasmus

    2017-01-01

    Identification of cryptic species can have profound implications in fishery management, conservation and biodiversity contexts. In the North Atlantic, the genus Sebastes is currently represented by four species, although additional cryptic species have been assumed. The connectivity of the gene...

  15. Genetic factors in Threatened Species Recovery Plans on three continents

    Science.gov (United States)

    Threatened species' recovery planning is applied globally to stem the current species extinction crisis. Evidence supports a key role of genetic processes, such as inbreeding depression, in determining species viability. We examined whether genetic factors are considered in threa...

  16. Variation in biofouling on different species of Indian timbers

    Digital Repository Service at National Institute of Oceanography (India)

    Raveendran, T.V.; Wagh, A.B.

    Biofouling on twenty species of wood exposed in waters of Mormugao Harbour, Goa, India have been presented. Macrofouling biomass varied from species to species. Maximum biomass was recorded on Artocarpus chaplasha (4 kg/m2) and minimum on Hopea...

  17. Hypoxylon species on beech and other broadleaves

    Directory of Open Access Journals (Sweden)

    Milijašević Tanja

    2004-01-01

    Full Text Available Fungi in the genus Hypoxylon cause wood decay and most of them are saprophytes on dead wood or parasites of weakness. The following species in this genus were identified in this study performed at several localities in Serbia and Montenegro: H. deustum, H. fragiforme, H. nummularium, H. multiforme, H. rubiginosum and H. fuscum. Among them the most significant species is H. deustum, the fungus causing root and butt rot of standing beech trees. It was recorded from all coppice and high forests of beech. This paper presents the morphological characteristics of the recorded fungi their range, plant hosts and significance.

  18. Functional biology of sympatric krill species

    DEFF Research Database (Denmark)

    Agersted, Mette Dalgaard; Nielsen, Torkel Gissel

    2016-01-01

    Here we compare the functional biology of the sympatric krill species, Meganyctiphanes norvegica and Thysanoessa inermis. For M. norvegica, we investigated functional responses on diatoms and copepods, together with prey size spectra on plankton ,400 mm and copepods in the size range 500–3220 mm....... For T. inermis, only prey size spectrum on plankton ,400 mm were investigated. The prey size ranges of both species include organisms ,400 mm, and they consequently graze on several trophic levels. However, T. inermis feed on cells ,10 mm equivalent spherical diameter (ESD), whereas M. norvegica only...

  19. Molecular activation analysis for chemical species studies

    International Nuclear Information System (INIS)

    Chai Zhifang; Mao Xueying; Wang Yuqi; Sun Jingxin; Qian Qingfang; Hou Xiaolin; Zhang Peiqun; Chen Chunying; Feng Weiyu; Ding Wenjun; Li Xiaolin; Li Chunsheng; Dai Xiongxin

    2001-01-01

    The Molecular Activation Analysis (MAA) mainly refers to an activation analysis method that is able to provide information about the chemical species of elements in systems of interest, though its exact definition has remained to be assigned. Its development is strongly stimulated by the urgent need to know the chemical species of elements, because the bulk contents or concentrations are often insignificant for judging biological, environmental or geochemical effects of elements. In this paper, the features, methodology and limitation of MAA were outlined. Further, the up-to-date MAA progress made in our laboratory was introduced as well. (author)

  20. A new dimension in documenting new species

    DEFF Research Database (Denmark)

    Akkari, Nesrine; Enghoff, Henrik; Metscher, Brian D.

    2015-01-01

    We review the state-of-the-art approaches currently applied in myriapod taxonomy, and we describe, for the first time, a new species of millipede (Ommatoiulus avatar n. sp., family Julidae) using high-resolution X-ray microtomography (microCT) as a substantive adjunct to traditional morphological...... examination. We present 3D models of the holotype and paratype specimens and discuss the potential of this non-destructive technique in documenting new species of millipedes and other organisms. The microCT data have been uploaded to an open repository (Dryad) to serve as the first actual millipede cybertypes...