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Sample records for oxysporum species complex

  1. First report of Fusarium oxysporum species complex infection in zebrafish culturing system.

    Science.gov (United States)

    Kulatunga, D C M; Dananjaya, S H S; Park, B K; Kim, C-H; Lee, J; De Zoysa, M

    2017-04-01

    Fusarium oxysporum species complex (FOSC) is a highly diverse fungus. Recently, F. oxysporum infection was identified from zebrafish (Danio rerio) culturing system in Korea. Initially, a rapid whitish smudge was appeared in the water with the fungal blooming on walls of fish tanks. Microscopic studies were conducted on fungal hyphae, colony pigmentation and chlamydospore formation and the presence of macro- and microspores confirmed that the isolated fungus as F. oxysporum. Furthermore, isolated F. oxysporum was confirmed by internal transcribed spacer sequencing which matched (100%) to nine F. oxysporum sequences available in GenBank. Experimental hypodermic injection of F. oxysporum into adult zebrafish showed the development of fungal mycelium and pathogenicity similar to signs observed. Histopathologic results revealed a presence of F. oxysporum hyphae in zebrafish muscle. Fusarium oxysporum growth was increased with sea salt in a concentration-dependent manner. Antifungal susceptibility results revealed that F. oxysporum is resistant to copper sulphate (up to 200 μg mL -1 ) and sensitive to nystatin (up to 40 μg mL -1 ). This is the first report of FOSC from zebrafish culture system, suggesting it appears as an emerging pathogen, thus posing a significant risk on zebrafish facilities in the world. © 2016 John Wiley & Sons Ltd.

  2. Mitochondrial genomes reveal recombination in the presumed asexual Fusarium oxysporum species complex.

    Science.gov (United States)

    Brankovics, Balázs; van Dam, Peter; Rep, Martijn; de Hoog, G Sybren; J van der Lee, Theo A; Waalwijk, Cees; van Diepeningen, Anne D

    2017-09-18

    The Fusarium oxysporum species complex (FOSC) contains several phylogenetic lineages. Phylogenetic studies identified two to three major clades within the FOSC. The mitochondrial sequences are highly informative phylogenetic markers, but have been mostly neglected due to technical difficulties. A total of 61 complete mitogenomes of FOSC strains were de novo assembled and annotated. Length variations and intron patterns support the separation of three phylogenetic species. The variable region of the mitogenome that is typical for the genus Fusarium shows two new variants in the FOSC. The variant typical for Fusarium is found in members of all three clades, while variant 2 is found in clades 2 and 3 and variant 3 only in clade 2. The extended set of loci analyzed using a new implementation of the genealogical concordance species recognition method support the identification of three phylogenetic species within the FOSC. Comparative analysis of the mitogenomes in the FOSC revealed ongoing mitochondrial recombination within, but not between phylogenetic species. The recombination indicates the presence of a parasexual cycle in F. oxysporum. The obstacles hindering the usage of the mitogenomes are resolved by using next generation sequencing and selective genome assemblers, such as GRAbB. Complete mitogenome sequences offer a stable basis and reference point for phylogenetic and population genetic studies.

  3. In vitro and in vivo antifungal efficacy of plant based lawsone against Fusarium oxysporum species complex.

    Science.gov (United States)

    Dananjaya, S H S; Udayangani, R M C; Shin, Sang Yeop; Edussuriya, M; Nikapitiya, Chamilani; Lee, Jehee; De Zoysa, Mahanama

    2017-08-01

    Fusarium oxysporum is an ascomycete facultative fungus which generally affects to plants. However, it is recently known as a serious emerging opportunistic pathogen of human and other animals. F. oxysporum shows broad resistance to commonly used antifungal agents and therefore development of alternative therapeutic agents is required. In this study, we investigated the antifungal efficacy of plant based natural lawsone against pathogenic F. oxysporum. Antifungal susceptibility test determined the concentration dependent growth inhibition of lawsone against F. oxysporum with minimum inhibitory concentration (MIC) at 100μg/mL. Ultra-structural analysis indicates the prominent damage on cell wall of the mycelium after lawsone treatment, and suggests that it could increase the membrane permeability and disintegration of cells leading to cellular death. Propidium iodide (PI) uptake assay results showed the higher level of cell death in lawsone treated F. oxysporum which further confirms the loss of plasma membrane integrity. Also, detection of reactive oxygen species (ROS) using DCFH-DA has clearly indicated that lawsone (100μg/mL) can induce the ROS level in the filaments of F. oxysporum. MTT assay results showed the loss of viability and germination capacity of F. oxysporum spores by lawsone in concentration dependent manner. Moreover, lawsone treatment induced the mRNA expression of two autophagy related genes (ATG1 and ATG8) indicating that lawsone may activate the autophagy related pathways in F. oxysporum due to the oxidative stress generated by ROS. F. oxysporum infected zebrafish has recovered after lawsone therapy as a topical treatment suggesting that lawsone is a potential natural antifusariosis agent. Copyright © 2017 Elsevier GmbH. All rights reserved.

  4. Comparative study on antifungal activities of chitosan nanoparticles and chitosan silver nano composites against Fusarium oxysporum species complex.

    Science.gov (United States)

    Dananjaya, S H S; Erandani, W K C U; Kim, Cheol-Hee; Nikapitiya, Chamilani; Lee, Jehee; De Zoysa, Mahanama

    2017-12-01

    Though the metal nanoparticles (NPs) have been shown favorable results against fungal diseases, erratic environmental toxicity of NPs have raised serious concerns against their applications. Hence, it is vital to modify antifungal compounds into safe substitutes over synthetic chemicals. In this study, antifungal effects of chitosan nanoparticles (CNPs) and chitosan silver nanocomposites (CAgNCs) were compared against Fusarium oxysporum species complex. CNPs and CAgNCs were synthesized, characterized and compared based on the transmission electron microscope, X-ray diffraction, UV-vis absorbance spectra, particle size distribution, zeta potential and thermal stability analysis. Ultra-structural analysis on mycelium membrane of treated F. oxysporum showed that CNPs and CAgNCs could induce a pronounced membrane damage and disruption of the mycelium surface, increase the membrane permeability, and even cell disintegration. CAgNCs showed a significantly higher radial growth inhibition than CNPs in all the tested concentrations. Both CNPs and CAgNCs were not only effective in reducing the fungal growth, but also caused morphological and ultrastructural changes in the pathogen, thereby suggesting its usage as an antifungal dispersion system to control F. oxysporum. Additionally, CNPs and CAgNCs therapy reduced the F. oxysporum infection in zebrafish. Data demonstrates biologically active CNPs and CAgNCs are promising antifungal agents against F. oxysporum. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. A two-locus DNA sequence database for typing plant and human pathogens within the Fusarium oxysporum species complex

    DEFF Research Database (Denmark)

    O'Donnell, Kerry; Gueidan, C; Sink, S

    2009-01-01

    We constructed a two-locus database, comprising partial translation elongation factor (EF-1alpha) gene sequences and nearly full-length sequences of the nuclear ribosomal intergenic spacer region (IGS rDNA) for 850 isolates spanning the phylogenetic breadth of the Fusarium oxysporum species compl...... of the IGS rDNA sequences may be non-orthologous. We also evaluated enniatin, fumonisin and moniliformin mycotoxin production in vitro within a phylogenetic framework....

  6. Sorne aspects of Fusarium genus and the Fusarium oxysporum species Algunos aspectos de los hongos del genero Fusarium y de la especie Fusarium oxysporum

    Directory of Open Access Journals (Sweden)

    Arbeláez Torres Germán

    2000-12-01

    Full Text Available Since the proposal of the utilization of the fungus Fusarium oxysporum for biological control of coca plants in Colombia, there is a serious discussion on different Colombian meetings about the advantages and disadvantages of its application. However in these discussions there was not enough knowledge of the fungus Fusarium oxysporum. This paper presents sorne biological and pathological aspects ofthe genus Fusarium and the species Fusarium oxysporum.Ante la propuesta de utilizar el hongo Fusarium oxysporum
    f.sp. erythoxyli para el control biológico de las plantas de
    coca en Colombia, se ha abierto una amplia discusión en distintos ámbitos nacionales sobre las bondades y los aspectos
    negativos de su aplicación. Sin embargo, en dicha discusión
    se ha notado un gran desconocimiento sobre el hongo
    Fusarium oxysporum. En este artículo se presentan diversos
    aspectos biológicos y patológicos del género Fusarium y de
    la especie Fusarium oxysporum.

  7. Evolutionary relationships between Fusarium oxysporum f. sp. lycopersici and F. oxysporum f. sp. radicis-lycopersici isolates inferred from mating type, elongation factor-1a exopolygalacturonase sequences

    NARCIS (Netherlands)

    Lievens, B.; Baarlen, van P.; Verreth, C.; Kerckhove, van S.; Rep, M.; Thomma, B.P.H.J.

    2009-01-01

    Fusarium oxysporum is a ubiquitous species complex of soilborne plant pathogens that comprises many different formae speciales, each characterized by a high degree of host specificity. In this study, the evolutionary relationships between different isolates of the F. oxysporum species complex have

  8. Biocontrol Effectiveness of Indigenous Trichoderma Species against Meloidogyne javanica and Fusarium oxysporum f. sp. radicis lycopersici on Tomato

    OpenAIRE

    Hajji Lobna; Chattaoui Mayssa; Regaieg Hajer; M'Hamdi-Boughalleb Naima; Rhouma Ali; Horrigue-Raouani Najet

    2016-01-01

    In this study, three local isolates of Trichoderma (Tr1: T. viride, Tr2: T. harzianum and Tr3: T. asperellum) were isolated and evaluated for their biocontrol effectiveness under in vitro conditions and in greenhouse. In vitro bioassay revealed a biopotential control against Fusarium oxysporum f. sp. radicis lycopersici and Meloidogyne javanica (RKN) separately. All species of Trichoderma exhibited biocontrol performance and (Tr1) Trichoderma viride was the most efficient. In fact, growth rat...

  9. Bacillus species (BT42) isolated from Coffea arabica L. rhizosphere antagonizes Colletotrichum gloeosporioides and Fusarium oxysporum and also exhibits multiple plant growth promoting activity.

    Science.gov (United States)

    Kejela, Tekalign; Thakkar, Vasudev R; Thakor, Parth

    2016-11-18

    Colletotrichum and Fusarium species are among pathogenic fungi widely affecting Coffea arabica L., resulting in major yield loss. In the present study, we aimed to isolate bacteria from root rhizosphere of the same plant that is capable of antagonizing Colletotrichum gloeosporioides and Fusarium oxysporum as well as promotes plant growth. A total of 42 Bacillus species were isolated, one of the isolates named BT42 showed maximum radial mycelial growth inhibition against Colletotrichum gloeosporioides (78%) and Fusarium oxysporum (86%). BT42 increased germination of Coffee arabica L. seeds by 38.89%, decreased disease incidence due to infection of Colletotrichum gloeosporioides to 2.77% and due to infection of Fusarium oxysporum to 0 (p Fusarium oxysporum. The mechanism of action of inhibition of the pathogenic fungi found to be synergistic effects of secondary metabolites, lytic enzymes, and siderophores. The major inhibitory secondary metabolite identified as harmine (β-carboline alkaloids).

  10. Fusarium oxysporum and the Fusarium Wilt Syndrome.

    Science.gov (United States)

    Gordon, Thomas R

    2017-08-04

    The Fusarium oxysporum species complex (FOSC) comprises a multitude of strains that cause vascular wilt diseases of economically important crops throughout the world. Although sexual reproduction is unknown in the FOSC, horizontal gene transfer may contribute to the observed diversity in pathogenic strains. Development of disease in a susceptible crop requires F. oxysporum to advance through a series of transitions, beginning with spore germination and culminating with establishment of a systemic infection. In principle, each transition presents an opportunity to influence the risk of disease. This includes modifications of the microbial community in soil, which can affect the ability of pathogen propagules to survive, germinate, and infect plant roots. In addition, many host attributes, including the composition of root exudates, the structure of the root cortex, and the capacity to recognize and respond quickly to invasive growth of a pathogen, can impede development of F. oxysporum.

  11. Molecular genetic characterization of the koa-wilt pathogen (Fusarium oxysporum): Application of molecular genetic tools toward improving koa restoration in Hawai'i

    Science.gov (United States)

    Mee-Sook Kim; Jane E. Stewart; Nicklos Dudley; John Dobbs; Tyler Jones; Phil G. Cannon; Robert L. James; Kas Dumroese; Ned B. Klopfenstein

    2015-01-01

    Several forest diseases are causing serious threats to the native Hawaiian forest. Among them, koawilt disease (caused by Fusarium oxysporum) is damaging to native populations of koa (Acacia koa), and it also hinders koa restoration/reforestation. Because F. oxysporum likely represents a complex of species with distinct pathogenic activities, more detailed...

  12. Degradation of the metal-cyano complex tetracyanonickelate (II) by Fusarium oxysporum N-10.

    Science.gov (United States)

    Yanase, H; Sakamoto, A; Okamoto, K; Kita, K; Sato, Y

    2000-03-01

    A fungus with the ability to utilize a metalcyano compound, tetracyanonickelate (II) ¿K2[Ni (CN)4]; TCN¿, as its sole source of nitrogen was isolated from soil and identified as Fusarium oxysporum N-10. Both intact mycelia and cell-free extract of the strain catalyzed hydrolysis of TCN to formate and ammonia and produced formamide as an intermediate, thereby indicating that a hydratase and an amidase sequentially participated in the degradation of TCN. The enzyme catalyzing the hydration of TCN was purified approximately ten-fold from the cell-free extract of strain N-10 with a yield of 29%. The molecular mass of the active enzyme was estimated to be 160 kDa. The enzyme appears to exist as a homotetramer, each subunit having a molecular mass of 40 kDa. The enzyme also catalyzed the hydration of KCN, with a cyanide-hydrating activity 2 x 10(4) times greater than for TCN. The kinetic parameters for TCN and KCN indicated that hydratase isolated from F. oxysporum was a cyanide hydratase able to utilize a broad range of cyano compounds and nitriles as substrates.

  13. Use of Comparative Genomics-Based Markers for Discrimination of Host Specificity in Fusarium oxysporum.

    Science.gov (United States)

    van Dam, Peter; de Sain, Mara; Ter Horst, Anneliek; van der Gragt, Michelle; Rep, Martijn

    2018-01-01

    their host range, which is normally restricted to only one or a few plant species. However, horizontal gene transfer between strains in the species complex has resulted in a polyphyletic origin of host specificity in many of these formae speciales This hinders accurate and rapid pathogen detection through molecular methods. In our research, we compared the genomes of 88 strains of F. oxysporum with each other, specifically targeting virulence-related genes that are typically highly similar within each forma specialis Using this approach, we identified marker sequences that allow the discrimination of F. oxysporum strains affecting various cucurbit plant species through different PCR-based methods. Copyright © 2017 American Society for Microbiology.

  14. CCR4-Not Complex Subunit Not2 Plays Critical Roles in Vegetative Growth, Conidiation and Virulence in Watermelon Fusarium Wilt Pathogen Fusarium oxysporum f. sp. niveum

    Science.gov (United States)

    Dai, Yi; Cao, Zhongye; Huang, Lihong; Liu, Shixia; Shen, Zhihui; Wang, Yuyan; Wang, Hui; Zhang, Huijuan; Li, Dayong; Song, Fengming

    2016-01-01

    CCR4-Not complex is a multifunctional regulator that plays important roles in multiple cellular processes in eukaryotes. In the present study, the biological function of FonNot2, a core subunit of the CCR4-Not complex, was explored in Fusarium oxysporum f. sp. niveum (Fon), the causal agent of watermelon wilt disease. FonNot2 was expressed at higher levels in conidia and germinating conidia and during infection in Fon-inoculated watermelon roots than in mycelia. Targeted disruption of FonNot2 resulted in retarded vegetative growth, reduced conidia production, abnormal conidial morphology, and reduced virulence on watermelon. Scanning electron microscopy observation of infection behaviors and qRT-PCR analysis of in planta fungal growth revealed that the ΔFonNot2 mutant was defective in the ability to penetrate watermelon roots and showed reduced fungal biomass in root and stem of the inoculated plants. Phenotypic and biochemical analyses indicated that the ΔFonNot2 mutant displayed hypersensitivity to cell wall perturbing agents (e.g., Congo Red and Calcofluor White) and oxidative stress (e.g., H2O2 and paraquat), decreased fusaric acid content, and reduced reactive oxygen species (ROS) production during spore germination. Our data demonstrate that FonNot2 plays critical roles in regulating vegetable growth, conidiogenesis and conidia morphology, and virulence on watermelon via modulating cell wall integrity, oxidative stress response, ROS production and FA biosynthesis through the regulation of transcription of genes involved in multiple pathways. PMID:27695445

  15. Host specificity in Fusarium oxysporum

    NARCIS (Netherlands)

    van Dam, P.

    2017-01-01

    Fusarium oxysporum is a fungal pathogen that can cause severe wilt disease and root rot in various plant species. Every individual strain is restricted to causing disease in only one or a few plant species. In this thesis, we focused on identifying novel virulence factors (‘effectors’) secreted by

  16. How Phytohormones Shape Interactions between Plants and the Soil-Borne Fungus Fusarium oxysporum

    NARCIS (Netherlands)

    Di, X.; Takken, F.L.W.; Tintor, N.

    2016-01-01

    Plants interact with a huge variety of soil microbes, ranging from pathogenic to mutualistic. The Fusarium oxysporum (Fo) species complex consists of ubiquitous soil inhabiting fungi that can infect and cause disease in over 120 different plant species including tomato, banana, cotton, and

  17. Biological control of wilt disease complex on tomato crop caused by Meloidogyne javanica and Fusarium oxysporum f.sp. lycopersici by Verticillium leptobactrum.

    Science.gov (United States)

    Hajji-Hedfi, Lobna; Regaieg, Hajer; Larayedh, Asma; Chihani, Noura; Horrigue-Raouani, Najet

    2017-09-23

    The efficacy of Verticillium leptobactrum isolate (HR1) was evaluated in the control of root-knot nematode and Fusarium wilt fungus under laboratory and greenhouse conditions. Five concentrations of V. leptobactrum (HR1) isolate were tested for their nematicidal and fungicidal activities against Meloidogyne javanica and Fusarium oxysporum f.sp. lycopersici in vitro. Laboratory trials showed that mycelium growth inhibition of Fusarium wilt fungus was correlated to the increase of the concentration of culture filtrate. All dilutions showed efficiency in reducing the growth of Fusarium oxysporum f.sp. lycopersici. The greatest nematicidal activity was observed at 50, 75, and 100% filtrate dilutions. The egg hatching percentage reached 42%, and the juvenile's corrected mortality registered 90% for the above treatments. In greenhouse experiment, the biocontrol agent fungus enhanced significantly tomato growth components (height and weight of plant and root). The multiplication rate of root-knot nematode and the Fusarium wilt disease incidence declined significantly with soil application of V. leptobactrum as with chemical treatments. The isolate HR1 was efficient to control wilt disease complex caused by M. javanica and Fusarium oxysporum f.sp. lycopersici.

  18. Fusarium oxysporum protects Douglas-fir (Pseudotsuga menziesii) seedlings from root disease caused by Fusarium commune

    Science.gov (United States)

    R. Kasten Dumroese; Mee-Sook Kim; Robert L. James

    2012-01-01

    Fusarium root disease can be a serious problem in forest and conservation nurseries in the western United States. Fusarium inoculum is commonly found in most container and bareroot nurseries on healthy and diseased seedlings, in nursery soils, and on conifer seeds. Fusarium spp. within the F. oxysporum species complex have been recognized as pathogens for more than a...

  19. 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

  20. Effector profiles distinguish formae speciales of Fusarium oxysporum.

    Science.gov (United States)

    van Dam, Peter; Fokkens, Like; Schmidt, Sarah M; Linmans, Jasper H J; Kistler, H Corby; Ma, Li-Jun; Rep, Martijn

    2016-11-01

    Formae speciales (ff.spp.) of the fungus Fusarium oxysporum are often polyphyletic within the species complex, making it impossible to identify them on the basis of conserved genes. However, sequences that determine host-specific pathogenicity may be expected to be similar between strains within the same forma specialis. Whole genome sequencing was performed on strains from five different ff.spp. (cucumerinum, niveum, melonis, radicis-cucumerinum and lycopersici). In each genome, genes for putative effectors were identified based on small size, secretion signal, and vicinity to a "miniature impala" transposable element. The candidate effector genes of all genomes were collected and the presence/absence patterns in each individual genome were clustered. Members of the same forma specialis turned out to group together, with cucurbit-infecting strains forming a supercluster separate from other ff.spp. Moreover, strains from different clonal lineages within the same forma specialis harbour identical effector gene sequences, supporting horizontal transfer of genetic material. These data offer new insight into the genetic basis of host specificity in the F. oxysporum species complex and show that (putative) effectors can be used to predict host specificity in F. oxysporum. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  1. Species and ecological diversity within the Cladosporium cladosporioides complex (Davidiellaceae, Capnodiales)

    DEFF Research Database (Denmark)

    Bensch, K.; Groenewald, J.Z.; Dijksterhuis, J.

    2010-01-01

    of this species. Cladosporium tenuissimum and C. oxysporum, two saprobes abundant in the tropics, are epitypified and shown to be allied to, but distinct from C. cladosporioides. Twenty-two species are newly described on the basis of phylogenetic characters and cryptic morphological differences. The most...... important phenotypic characters for distinguishing species within the C. cladosporioides complex, which represents a monophyletic subclade within the genus, are shape, width, length, septation and surface ornamentation of conidia and conidiophores; length and branching patterns of conidial chains and hyphal...... shape, width and arrangement. Many of the treated species, e.g., C. acalyphae, C. angustisporum, C. australiense, C. basiinflatum, C. chalastosporoides, C. colocasiae, C. cucumerinum, C. exasperatum, C. exile, C. flabelliforme, C. gamsianum, and C. globisporum are currently known only from specific...

  2. 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

  3. Races of the Celery Pathogen Fusarium oxysporum f. sp. apii Are Polyphyletic.

    Science.gov (United States)

    Epstein, Lynn; Kaur, Sukhwinder; Chang, Peter L; Carrasquilla-Garcia, Noelia; Lyu, Guiyun; Cook, Douglas R; Subbarao, Krishna V; O'Donnell, Kerry

    2017-04-01

    Fusarium oxysporum species complex (FOSC) isolates were obtained from celery with symptoms of Fusarium yellows between 1993 and 2013 primarily in California. Virulence tests and a two-gene dataset from 174 isolates indicated that virulent isolates collected before 2013 were a highly clonal population of F. oxysporum f. sp. apii race 2. In 2013, new highly virulent clonal isolates, designated race 4, were discovered in production fields in Camarillo, California. Long-read Illumina data were used to analyze 16 isolates: six race 2, one of each from races 1, 3, and 4, and seven genetically diverse FOSC that were isolated from symptomatic celery but are nonpathogenic on this host. Analyses of a 10-gene dataset comprising 38 kb indicated that F. oxysporum f. sp. apii is polyphyletic; race 2 is nested within clade 3, whereas the evolutionary origins of races 1, 3, and 4 are within clade 2. Based on 6,898 single nucleotide polymorphisms from the core FOSC genome, race 3 and the new highly virulent race 4 are highly similar with Nei's Da = 0.0019, suggesting that F. oxysporum f. sp. apii race 4 evolved from race 3. Next generation sequences were used to develop PCR primers that allow rapid diagnosis of races 2 and 4 in planta.

  4. Fusarium oxysporum volatiles enhance plant growth via affecting auxin transport and signaling

    Directory of Open Access Journals (Sweden)

    Vasileios eBitas

    2015-11-01

    Full Text Available Volatile organic compounds (VOCs have well-documented roles in plant-plant communication and directing animal behavior. In this study, we examine the less understood roles of VOCs in plant-fungal relationships. Phylogenetically and ecologically diverse strains of Fusarium oxysporum, a fungal species complex that often resides in the rhizosphere of assorted plants, produce volatile compounds that augment shoot and root growth of Arabidopsis thaliana and tobacco. Growth responses of A. thaliana hormone signaling mutants and expression patterns of a GUS reporter gene under the auxin-responsive DR5 promoter supported the involvement of auxin signaling in F. oxysporum volatile-mediated growth enhancement. In addition, 1-naphthylthalamic acid, an inhibitor of auxin efflux, negated F. oxysporum volatile-mediated growth enhancement in both plants. Comparison of the profiles of volatile compounds produced by F. oxysporum strains that differentially affected plant growth suggests that the relative compositions of both growth inhibitory and stimulatory compounds may determine the degree of plant growth enhancement. Volatile-mediated signaling between fungi and plants may represent a potentially conserved, yet mostly overlooked, mechanism underpinning plant-fungus interactions and fungal niche adaption.

  5. 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

  6. Biomass production and secretion of hydrolytic enzymes are influenced by the structural complexity of the nitrogen source in Fusarium oxysporum and Aspergillus nidulans.

    Science.gov (United States)

    da Silva, M C; Bertolini, M C; Ernandes, J R

    2001-01-01

    The structural complexity of the nitrogen sources strongly affects biomass production and secretion of hydrolytic enzymes in filamentous fungi. Fusarium oxysporum and Aspergillus nidulans were grown in media containing glucose or starch, and supplemented with a nitrogen source varying from a single ammonium salt (ammonium sulfate) to free amino acids (casamino acids), peptides (peptone) and protein (gelatin). In glucose, when the initial pH was adjusted to 5.0, for both microorganisms, higher biomass production occurred upon supplementation with a nitrogen source in the peptide form (peptone and gelatin). With a close to neutrality pH, biomass accumulation was lower only in the presence of the ammonium salt. When grown in starch, biomass accumulation and secretion of hydrolytic enzymes (amylolytic and proteolytic) by Fusarium also depended on the nature of the nitrogen supplement and the pH. When the initial pH was adjusted to 5.0, higher growth and higher amylolytic activities were detected in the media supplemented with peptone, gelatin and casamino acids. However, at pH 7.0, higher biomass accumulation and higher amylolytic activities were observed upon supplementation with peptone or gelatin. Ammonium sulfate and casamino acids induced a lower production of biomass, and a different level of amylolytic enzyme secretion: high in ammonium sulfate and low in casamino acids. Secretion of proteolytic activity was always higher in the media supplemented with peptone and gelatin. Aspergillus, when grown in starch, was not as dependent as Fusarium on the nature of nitrogen source or the pH. The results described in this work indicate that the metabolism of fungi is regulated not only by pH, but also by the level of structural complexity of the nitrogen source in correlation to the carbon source.

  7. 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 ...

  8. 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 ...

  9. A high efficiency gene disruption strategy using a positive-negative split selection marker and electroporation for Fusarium oxysporum.

    Science.gov (United States)

    Liang, Liqin; Li, Jianqiang; Cheng, Lin; Ling, Jian; Luo, Zhongqin; Bai, Miao; Xie, Bingyan

    2014-11-01

    The Fusarium oxysporum species complex consists of fungal pathogens that cause serial vascular wilt disease on more than 100 cultivated species throughout the world. Gene function analysis is rapidly becoming more and more important as the whole-genome sequences of various F. oxysporum strains are being completed. Gene-disruption techniques are a common molecular tool for studying gene function, yet are often a limiting step in gene function identification. In this study we have developed a F. oxysporum high-efficiency gene-disruption strategy based on split-marker homologous recombination cassettes with dual selection and electroporation transformation. The method was efficiently used to delete three RNA-dependent RNA polymerase (RdRP) genes. The gene-disruption cassettes of three genes can be constructed simultaneously within a short time using this technique. The optimal condition for electroporation is 10μF capacitance, 300Ω resistance, 4kV/cm field strength, with 1μg of DNA (gene-disruption cassettes). Under these optimal conditions, we were able to obtain 95 transformants per μg DNA. And after positive-negative selection, the transformants were efficiently screened by PCR, screening efficiency averaged 85%: 90% (RdRP1), 85% (RdRP2) and 77% (RdRP3). This gene-disruption strategy should pave the way for high throughout genetic analysis in F. oxysporum. Copyright © 2014 Elsevier GmbH. All rights reserved.

  10. Novel taxa in the Fusarium fujikuroi species complex from Pinus spp.

    Science.gov (United States)

    Herron, D.A.; Wingfield, M.J.; Wingfield, B.D.; Rodas, C.A.; Marincowitz, S.; Steenkamp, E.T.

    2015-01-01

    The pitch canker pathogen Fusarium circinatum has caused devastation to Pinus spp. in natural forests and non-natives in commercially managed plantations. This has drawn attention to the potential importance of Fusarium species as pathogens of forest trees. In this study, we explored the diversity of Fusarium species associated with diseased Pinus patula, P. tecunumanii, P. kesiya and P. maximinoi in Colombian plantations and nurseries. Plants displaying symptoms associated with a F. circinatum-like infection (i.e., stem cankers and branch die-back on trees in plantations and root or collar rot of seedlings) were sampled. A total of 57 isolates were collected and characterised based on DNA sequence data for the translation elongation factor 1-α and β-tubulin gene regions. Phylogenetic analyses of these data allowed for the identification of more than 10 Fusarium species. These included F. circinatum, F. oxysporum, species within the Fusarium solani species complex and seven novel species in the Fusarium fujikuroi species complex (formerly the Gibberella fujikuroi species complex), five of which are described here as new. Selected isolates of the new species were tested for their pathogenicity on Pinus patula and compared with that of F. circinatum. Of these, F. marasasianum, F. parvisorum and F. sororula displayed levels of pathogenicity to P. patula that were comparable with that of F. circinatum. These apparently emerging pathogens thus pose a significant risk to forestry in Colombia and other parts of the world. PMID:26955193

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

    Indian Academy of Sciences (India)

    [Banerjee P. and Singh B. N. 2017 The Drosophila bipectinata species complex: phylogenetic relationship among different members based on chromosomal variations. J. Genet. 96, 97–107]. Introduction ..... loops touch the chromocenter and in our microphotograph. (depicting both the arms) too, the involvement of chromo-.

  12. Association of Effector Six6 with Vascular Wilt Symptoms Caused by Fusarium oxysporum on Soybean.

    Science.gov (United States)

    Lanubile, Alessandra; Ellis, Margaret L; Marocco, Adriano; Munkvold, Gary P

    2016-11-01

    The Fusarium oxysporum species complex (FOSC) is a widely distributed group of fungi that includes both pathogenic and nonpathogenic isolates. In a previous study, isolates within the FOSC collected primarily from soybean were assessed for the presence of 12 fungal effector genes. Although none of the assayed genes was significantly associated with wilt symptoms on soybean, the secreted in xylem 6 (Six6) gene was present only in three isolates, which all produced high levels of vascular wilt on soybean. In the current study, a collection of F. oxysporum isolates from soybean roots and F. oxysporum f. sp. phaseoli isolates from common bean was screened for the presence of the Six6 gene. Interestingly, all isolates for which the Six6 amplicon was generated caused wilt symptoms on soybean, and two-thirds of the isolates showed high levels of aggressiveness, indicating a positive association between the presence of the effector gene Six6 and induction of wilt symptoms. The expression profile of the Six6 gene analyzed by quantitative reverse-transcription polymerase chain reaction revealed an enhanced expression for the isolates that caused more severe wilt symptoms on soybean, as established by the greenhouse assay. These findings suggest the suitability of the Six6 gene as a possible locus for pathogenicity-based molecular diagnostics across the various formae speciales.

  13. A newly developed real-time PCR assay for detection and quantification of Fusarium oxysporum and its use in compatible and incompatible interactions with grafted melon genotypes.

    Science.gov (United States)

    Haegi, Anita; Catalano, Valentina; Luongo, Laura; Vitale, Salvatore; Scotton, Michele; Ficcadenti, Nadia; Belisario, Alessandra

    2013-08-01

    A reliable and species-specific real-time quantitative polymerase chain reaction (qPCR) assay was developed for detection of the complex soilborne anamorphic fungus Fusarium oxysporum. The new primer pair, designed on the translation elongation factor 1-α gene with an amplicon of 142 bp, was highly specific to F. oxysporum without cross reactions with other Fusarium spp. The protocol was applied to grafted melon plants for the detection and quantification of F. oxysporum f. sp. melonis, a devastating pathogen of this cucurbit. Grafting technologies are widely used in melon to confer resistance against new virulent races of F. oxysporum f. sp. melonis, while maintaining the properties of valuable commercial varieties. However, the effects on the vascular pathogen colonization have not been fully investigated. Analyses were performed on 'Charentais-T' (susceptible) and 'Nad-1' (resistant) melon cultivars, both used either as rootstock and scion, and inoculated with F. oxysporum f. sp. melonis race 1 and race 1,2. Pathogen development was compared using qPCR and isolations from stem tissues. Early asymptomatic melon infections were detected with a quantification limit of 1 pg of fungal DNA. The qPCR protocol clearly showed that fungal development was highly affected by host-pathogen interaction (compatible or incompatible) and time (days postinoculation). The principal significant effect (P ≤ 0.01) on fungal development was due to the melon genotype used as rootstock, and this effect had a significant interaction with time and F. oxysporum f. sp. melonis race. In particular, the amount of race 1,2 DNA was significantly higher compared with that estimated for race 1 in the incompatible interaction at 18 days postinoculation. The two fungal races were always present in both the rootstock and scion of grafted plants in either the compatible or incompatible interaction.

  14. Interaction of Fusarium oxysporum with Meloidogyne incognita on Roselle

    Directory of Open Access Journals (Sweden)

    K. H. Ooi

    1999-12-01

    Full Text Available Forty isolates of Fusarium oxysporum were tested for their pathogenicity to roselle (Hibiscus sabdariffa L. var. sabdariffa in a plant house. The most virulent isolate was later used in a disease complex experiment with a root-knot nematode Meloidogyne incognita. Disease severity of roselle seedlings inoculated with a combination of fungus and nematode was higher than those inoculated with either fungus or nematode individually. Seedlings that were inoculated with fungus two weeks after nematode inoculation showed the highest disease severity compared to that inoculated with nematode two weeks after fungal inoculation or that inoculated simultaneously with both pathogens. It seems that root infections by M. incognita increased the colonization of roselle by F. oxysporum and subsequently caused higher damage to the roselle seedlings. The high wilt incidence in the presence of M. incognita and F. oxysporum may be due to the synergistic relationship between these two pathogens.

  15. 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 ...

  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. Diversity of the Cryptococcus neoformans-Cryptococcus gattii species complex.

    NARCIS (Netherlands)

    Bovers, M.; Hagen, F.; Boekhout, T.

    2008-01-01

    More than 110 years of study of the Cryptococcus neoformans and Cryptococcus gattii species complex has resulted in an enormous accumulation of fundamental and applied biological and clinical knowledge. Recent developments in our understanding of the diversity within the species complex are

  19. Phylogeny of Fomitopsis pinicola: A species complex

    Science.gov (United States)

    John Haight; Gary A. Laursen; Jessie A. Glaeser; D. Lee. Taylor

    2016-01-01

    Fungal species with a broad distribution may exhibit considerable genetic variation over their geographic ranges. Variation may develop among populations based on geographic isolation, lack of migration, and genetic drift, though this genetic variation may not always be evident when examining phenotypic characters. Fomitopsis pinicola is an...

  20. Double keystone bird in a keystone species complex.

    Science.gov (United States)

    Daily, G C; Ehrlich, P R; Haddad, N M

    1993-01-15

    Species in a Colorado subalpine ecosystem show subtle interdependences. Red-naped sapsuckers play two distinct keystone roles. They excavate nest cavities in fungus-infected aspens that are required as nest sites by two species of swallows, and they drill sap wells into willows that provide abundant nourishment for themselves, hummingbirds, orange-crowned warblers, chipmunks, and an array of other sap robbers. The swallows thus depend on, and the sap robbers benefit from, a keystone species complex comprised of sapsuckers, willows, aspens, and a heartwood fungus. Disappearance of any element of the complex could cause an unanticipated unraveling of the community.

  1. Phylogeography in Nassarius mud snails: Complex patterns in congeneric species.

    Directory of Open Access Journals (Sweden)

    Chuanliang Pu

    Full Text Available One major goal for phylogeographical studies is to elucidate respective roles of multiple evolutionary and ecological forces that shape the current distribution patterns. In marine and coastal ecosystems, it has been generated a common realization that species with enormous population size and pelagic larval stages can disperse across broad geographical scales, leading to weak or even no phylogeographical structure across large geographical scales. However, the violation of such realization has been frequently reported, and it remains largely unexplored on mechanisms responsible for various phylogeographical patterns observed in different species at varied geographical scales. Here, we used a species-rich genus Nassarius to assess and compare phylogeographical patterns in congeneric species, and discuss causes and consequences underlying varied phylogeographical patterns. Interestingly, we observed complex phylogeographical patterns both within single species and across multiple species, and multiple analyses showed varied levels of genetic heterogeneity among sites within and across species. Available evidence suggests that related species with similar biological characteristics may not be necessary to result in consistent phylogeographical patterns. Multiple factors, including larval ecology, interactions between dispersal and natural selection, and human activity-mediated dispersal, can partially explain the complex patterns observed in this study. Deep investigations should be performed on these factors, particularly their respective roles in determining evolutionary/ecological processes to form phylogeographical patterns in species with high dispersal capacities in marine and coastal ecosystems.

  2. Root defense analysis against Fusarium oxysporum reveals new regulators to confer resistance

    Science.gov (United States)

    Chen, Yi Chung; Wong, Chin Lin; Muzzi, Frederico; Vlaardingerbroek, Ido; Kidd, Brendan N.; Schenk, Peer M.

    2014-01-01

    Fusarium oxysporum is a root-infecting fungal pathogen that causes wilt disease on a broad range of plant species, including Arabidopsis thaliana. Investigation of the defense response against this pathogen had primarily been conducted using leaf tissue and little was known about the root defense response. In this study, we profiled the expression of root genes after infection with F. oxysporum by microarray analysis. In contrast to the leaf response, root tissue did not show a strong induction of defense-associated gene expression and instead showed a greater proportion of repressed genes. Screening insertion mutants from differentially expressed genes in the microarray uncovered a role for the transcription factor ETHYLENE RESPONSE FACTOR72 (ERF72) in susceptibility to F. oxysporum. Due to the role of ERF72 in suppressing programmed cell death and detoxifying reactive oxygen species (ROS), we examined the pub22/pub23/pub24 U-box type E3 ubiquitin ligase triple mutant which is known to possess enhanced ROS production in response to pathogen challenge. We found that the pub22/23/24 mutant is more resistant to F. oxysporum infection, suggesting that a heightened innate immune response provides protection against F. oxysporum. We conclude that root-mediated defenses against soil-borne pathogens can be provided at multiple levels. PMID:24998294

  3. Comparative genomics and prediction of conditionally dispensable sequences in legume-infecting Fusarium oxysporum formae speciales facilitates identification of candidate effectors.

    Science.gov (United States)

    Williams, Angela H; Sharma, Mamta; Thatcher, Louise F; Azam, Sarwar; Hane, James K; Sperschneider, Jana; Kidd, Brendan N; Anderson, Jonathan P; Ghosh, Raju; Garg, Gagan; Lichtenzveig, Judith; Kistler, H Corby; Shea, Terrance; Young, Sarah; Buck, Sally-Anne G; Kamphuis, Lars G; Saxena, Rachit; Pande, Suresh; Ma, Li-Jun; Varshney, Rajeev K; Singh, Karam B

    2016-03-05

    Soil-borne fungi of the Fusarium oxysporum species complex cause devastating wilt disease on many crops including legumes that supply human dietary protein needs across many parts of the globe. We present and compare draft genome assemblies for three legume-infecting formae speciales (ff. spp.): F. oxysporum f. sp. ciceris (Foc-38-1) and f. sp. pisi (Fop-37622), significant pathogens of chickpea and pea respectively, the world's second and third most important grain legumes, and lastly f. sp. medicaginis (Fom-5190a) for which we developed a model legume pathosystem utilising Medicago truncatula. Focusing on the identification of pathogenicity gene content, we leveraged the reference genomes of Fusarium pathogens F. oxysporum f. sp. lycopersici (tomato-infecting) and F. solani (pea-infecting) and their well-characterised core and dispensable chromosomes to predict genomic organisation in the newly sequenced legume-infecting isolates. Dispensable chromosomes are not essential for growth and in Fusarium species are known to be enriched in host-specificity and pathogenicity-associated genes. Comparative genomics of the publicly available Fusarium species revealed differential patterns of sequence conservation across F. oxysporum formae speciales, with legume-pathogenic formae speciales not exhibiting greater sequence conservation between them relative to non-legume-infecting formae speciales, possibly indicating the lack of a common ancestral source for legume pathogenicity. Combining predicted dispensable gene content with in planta expression in the model legume-infecting isolate, we identified small conserved regions and candidate effectors, four of which shared greatest similarity to proteins from another legume-infecting ff. spp. We demonstrate that distinction of core and potential dispensable genomic regions of novel F. oxysporum genomes is an effective tool to facilitate effector discovery and the identification of gene content possibly linked to host

  4. 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.

  5. Fusarium oxysporum Triggers Tissue-Specific Transcriptional Reprogramming in Arabidopsis thaliana

    Science.gov (United States)

    Lyons, Rebecca; Stiller, Jiri; Powell, Jonathan; Rusu, Anca; Manners, John M.; Kazan, Kemal

    2015-01-01

    Some of the most devastating agricultural diseases are caused by root-infecting pathogens, yet the majority of studies on these interactions to date have focused on the host responses of aerial tissues rather than those belowground. Fusarium oxysporum is a root-infecting pathogen that causes wilt disease on several plant species including Arabidopsis thaliana. To investigate and compare transcriptional changes triggered by F. oxysporum in different Arabidopsis tissues, we infected soil-grown plants with F. oxysporum and subjected root and leaf tissue harvested at early and late timepoints to RNA-seq analyses. At least half of the genes induced or repressed by F. oxysporum showed tissue-specific regulation. Regulators of auxin and ABA signalling, mannose binding lectins and peroxidases showed strong differential expression in root tissue. We demonstrate that ARF2 and PRX33, two genes regulated in the roots, promote susceptibility to F. oxysporum. In the leaves, defensins and genes associated with the response to auxin, cold and senescence were strongly regulated while jasmonate biosynthesis and signalling genes were induced throughout the plant. PMID:25849296

  6. Fusarium oxysporum triggers tissue-specific transcriptional reprogramming in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Rebecca Lyons

    Full Text Available Some of the most devastating agricultural diseases are caused by root-infecting pathogens, yet the majority of studies on these interactions to date have focused on the host responses of aerial tissues rather than those belowground. Fusarium oxysporum is a root-infecting pathogen that causes wilt disease on several plant species including Arabidopsis thaliana. To investigate and compare transcriptional changes triggered by F. oxysporum in different Arabidopsis tissues, we infected soil-grown plants with F. oxysporum and subjected root and leaf tissue harvested at early and late timepoints to RNA-seq analyses. At least half of the genes induced or repressed by F. oxysporum showed tissue-specific regulation. Regulators of auxin and ABA signalling, mannose binding lectins and peroxidases showed strong differential expression in root tissue. We demonstrate that ARF2 and PRX33, two genes regulated in the roots, promote susceptibility to F. oxysporum. In the leaves, defensins and genes associated with the response to auxin, cold and senescence were strongly regulated while jasmonate biosynthesis and signalling genes were induced throughout the plant.

  7. Natamycin and Azithromycin are Synergistic in vitro against Ocular Pathogenic Aspergillus flavus species complex and Fusarium solani species complex Isolates.

    Science.gov (United States)

    Guo, Haoyi; Zhou, Lutan; He, Yi; Gao, Chuanwen; Han, Lei; Xu, Yan

    2018-05-07

    The interaction of natamycin-azithromycin combination against 60 ocular fungal isolates was tested in vitro The combination produced 100% synergistic interactions when natamycin added azithromycin at 20, 40, 50 μg/ml against Aspergillus flavus species complex (AFSC) isolates and added azithromycin at 50 μg/ml against Fusarium solani species complex isolates. The combination with 50 μg/ml azithromycin enhanced natamycin's effect against AFSC isolates by reducing natamycin MICs from MIC 90 64μg/ml to MIC 90 0.031μg/ml. No antagonism was observed. Copyright © 2018 American Society for Microbiology.

  8. Species Diversity and Bird Feed in Residential Complex

    Science.gov (United States)

    Hadinoto; Suhesti, Eni

    2017-12-01

    Bird is one component of the ecosystem which has an important role in supporting the occurrence of an organism's life cycle. Therefore, the presence of birds in an area is important, because it can affect the existence and distribution of plant species. The purpose of this study is to calculate the diversity of bird species and identify the source of bird feed in the compound. This study was conducted by field surveys in the residential complex. In addition to the birds as a research object vegetation as habitat / foraging birds were also observed. Data were analyzed by using the bird diversity index, richenes index, bundance index, dominance analysis, analysis of bird distribution and analysis of the level of meeting types, while vegetation will be analyzed based on the type and part of what is eaten by birds. In Pandau Jaya housing complex, found as many as 12 species of birds which consists of seven families. Bird species often present is Cucak Kutilang (Pycnonotus aurigaster) of 20 individuals, Bondol Peking (Lonchura punctulata) 14 individuals and Perkutut Jawa (Geopelia striata) 10 individuals. Bird species diversity (H ‘) in Pandau Jaya housing complex is still relatively moderate with a value of 2.27, while the Evenness Index (E) of 0.91 and Richenes Index (R) of 2.45. Types of vegetation as a food source, among others: mango, guava, cherry, jackfruit, ketapang, coconut, areca, palm, banana, papaya, flowers and grasses.

  9. Performance of four Dactylorhiza species over a complex trophic gradient

    NARCIS (Netherlands)

    Dijk, E; Grootjans, AB

    Spontananeous distribution and survival in experimental plots of four marsh orchids (Dactylorhiza spp.) in a hay-meadow complex were related to mineral composition of groundwater, soil nutrient availability and species composition of the vegetation. Differences in Ca2+ contents of the groundwater

  10. The dynamic complexity of a three species food chain model

    International Nuclear Information System (INIS)

    Lv Songjuan; Zhao Min

    2008-01-01

    In this paper, a three-species food chain model is analytically investigated on theories of ecology and using numerical simulation. Bifurcation diagrams are obtained for biologically feasible parameters. The results show that the system exhibits rich complexity features such as stable, periodic and chaotic dynamics

  11. Transcriptome analysis of the fungal pathogen Fusarium oxysporum f. sp. medicaginis during colonisation of resistant and susceptible Medicago truncatula hosts identifies differential pathogenicity profiles and novel candidate effectors.

    Science.gov (United States)

    Thatcher, Louise F; Williams, Angela H; Garg, Gagan; Buck, Sally-Anne G; Singh, Karam B

    2016-11-03

    Pathogenic members of the Fusarium oxysporum species complex are responsible for vascular wilt disease on many important crops including legumes, where they can be one of the most destructive disease causing necrotrophic fungi. We previously developed a model legume-infecting pathosystem based on the reference legume Medicago truncatula and a pathogenic F. oxysporum forma specialis (f. sp.) medicaginis (Fom). To dissect the molecular pathogenicity arsenal used by this root-infecting pathogen, we sequenced its transcriptome during infection of a susceptible and resistant host accession. High coverage RNA-Seq of Fom infected root samples harvested from susceptible (DZA315) or resistant (A17) M. truncatula seedlings at early or later stages of infection (2 or 7 days post infection (dpi)) and from vegetative (in vitro) samples facilitated the identification of unique and overlapping sets of in planta differentially expressed genes. This included enrichment, particularly in DZA315 in planta up-regulated datasets, for proteins associated with sugar, protein and plant cell wall metabolism, membrane transport, nutrient uptake and oxidative processes. Genes encoding effector-like proteins were identified, including homologues of the F. oxysporum f. sp. lycopersici Secreted In Xylem (SIX) proteins, and several novel candidate effectors based on predicted secretion, small protein size and high in-planta induced expression. The majority of the effector candidates contain no known protein domains but do share high similarity to predicted proteins predominantly from other F. oxysporum ff. spp. as well as other Fusaria (F. solani, F. fujikori, F. verticilloides, F. graminearum and F. pseudograminearum), and from another wilt pathogen of the same class, a Verticillium species. Overall, this suggests these novel effector candidates may play important roles in Fusaria and wilt pathogen virulence. Combining high coverage in planta RNA-Seq with knowledge of fungal pathogenicity

  12. Evolutionary relationships within the Phytophthora cactorum species complex in Europe.

    Science.gov (United States)

    Pánek, Matěj; Fér, Tomáš; Mráček, Jaroslav; Tomšovský, Michal

    2016-01-01

    The Phytophthora cactorum species complex in Europe is composed of P. cactorum, Phytophthora hedraiandra, and a hybrid species Phytophthora × serendipita. Evolutionary analyses using the amplified fragment length polymorphism (AFLP) method were carried out on 133 isolates from 19 countries. The AFLP data were complemented by sequence analysis of three genes (ITS region of ribosomal RNA gene, phenolic acid decarboxylase - Pheca I, and Cytochrome oxidase - Cox I), morphometric analysis and cardinal temperature data. The high proportion of clonal genotypes, low gene flow among groups, which was defined by the structure analysis, and low Nei's gene diversity confirms the homothallic life cycle of the groups. On the other hand, the ITS, Cox I and Pheca I sequence data support occasional hybridization between species. The structure K = 5 grouping revealed two groups of hybrid origin (C2 and F). While the C2 group resembles P. × serendipita, the F group includes Finnish isolates characterized by high oogonial abortion rates and slow growth. The morphological characters routinely used in identification of Phytophthora species are not useful for delimitation of species from the P. cactorum complex. Therefore, we discuss the status of P. hedraiandra as a separate species. The epitypification of P. cactorum is proposed. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  13. Investigating the Association between Flowering Time and Defense in the Arabidopsis thaliana-Fusarium oxysporum Interaction

    Science.gov (United States)

    Lyons, Rebecca; Rusu, Anca; Stiller, Jiri; Powell, Jonathan; Manners, John M.; Kazan, Kemal

    2015-01-01

    Plants respond to pathogens either by investing more resources into immunity which is costly to development, or by accelerating reproductive processes such as flowering time to ensure reproduction occurs before the plant succumbs to disease. In this study we explored the link between flowering time and pathogen defense using the interaction between Arabidopsis thaliana and the root infecting fungal pathogen Fusarium oxysporum. We report that F. oxysporum infection accelerates flowering time and regulates transcription of a number of floral integrator genes, including FLOWERING LOCUS C (FLC), FLOWERING LOCUS T (FT) and GIGANTEA (GI). Furthermore, we observed a positive correlation between late flowering and resistance to F. oxysporum in A. thaliana natural ecotypes. Late-flowering gi and autonomous pathway mutants also exhibited enhanced resistance to F. oxysporum, supporting the association between flowering time and defense. However, epistasis analysis showed that accelerating flowering time by deletion of FLC in fve-3 or fpa-7 mutants did not alter disease resistance, suggesting that the effect of autonomous pathway on disease resistance occurs independently from flowering time. Indeed, RNA-seq analyses suggest that fve-3 mediated resistance to F. oxysporum is most likely a result of altered defense-associated gene transcription. Together, our results indicate that the association between flowering time and pathogen defense is complex and can involve both pleiotropic and direct effects. PMID:26034991

  14. Allopatric speciation within a cryptic species complex of Australasian octopuses.

    Science.gov (United States)

    Amor, Michael D; Norman, Mark D; Cameron, Hayley E; Strugnell, Jan M

    2014-01-01

    Despite extensive revisions over recent decades, the taxonomy of benthic octopuses (Family Octopodidae) remains in a considerable flux. Among groups of unresolved status is a species complex of morphologically similar shallow-water octopods from subtropical Australasia, including: Allopatric populations of Octopus tetricus on the eastern and western coasts of Australia, of which the Western Australian form is speculated to be a distinct or sub-species; and Octopus gibbsi from New Zealand, a proposed synonym of Australian forms. This study employed a combination of molecular and morphological techniques to resolve the taxonomic status of the 'tetricus complex'. Phylogenetic analyses (based on five mitochondrial genes: 12S rRNA, 16S rRNA, COI, COIII and Cytb) and Generalised Mixed Yule Coalescent (GMYC) analysis (based on COI, COIII and Cytb) distinguished eastern and Western Australian O. tetricus as distinct species, while O. gibbsi was found to be synonymous with the east Australian form (BS = >97, PP = 1; GMYC p = 0.01). Discrete morphological differences in mature male octopuses (based on sixteen morphological traits) provided further evidence of cryptic speciation between east (including New Zealand) and west coast populations; although females proved less useful in morphological distinction among members of the tetricus complex. In addition, phylogenetic analyses suggested populations of octopuses currently treated under the name Octopus vulgaris are paraphyletic; providing evidence of cryptic speciation among global populations of O. vulgaris, the most commercially valuable octopus species worldwide.

  15. Transcontinental phylogeography of the Daphnia pulex species complex.

    Science.gov (United States)

    Crease, Teresa J; Omilian, Angela R; Costanzo, Katie S; Taylor, Derek J

    2012-01-01

    Daphnia pulex is quickly becoming an attractive model species in the field of ecological genomics due to the recent release of its complete genome sequence, a wide variety of new genomic resources, and a rich history of ecological data. Sequences of the mitochondrial NADH dehydrogenase subunit 5 and cytochrome c oxidase subunit 1 genes were used to assess the global phylogeography of this species, and to further elucidate its phylogenetic relationship to other members of the Daphnia pulex species complex. Using both newly acquired and previously published data, we analyzed 398 individuals from collections spanning five continents. Eleven strongly supported lineages were found within the D. pulex complex, and one lineage in particular, panarctic D. pulex, has very little phylogeographical structure and a near worldwide distribution. Mismatch distribution, haplotype network, and population genetic analyses are compatible with a North American origin for this lineage and subsequent spatial expansion in the Late Pleistocene. In addition, our analyses suggest that dispersal between North and South America of this and other species in the D. pulex complex has occurred multiple times, and is predominantly from north to south. Our results provide additional support for the evolutionary relationships of the eleven main mitochondrial lineages of the D. pulex complex. We found that the well-studied panarctic D. pulex is present on every continent except Australia and Antarctica. Despite being geographically very widespread, there is a lack of strong regionalism in the mitochondrial genomes of panarctic D. pulex--a pattern that differs from that of most studied cladocerans. Moreover, our analyses suggest recent expansion of the panarctic D. pulex lineage, with some continents sharing haplotypes. The hypothesis that hybrid asexuality has contributed to the recent and unusual geographic success of the panarctic D. pulex lineage warrants further study.

  16. Allopatric Speciation within a Cryptic Species Complex of Australasian Octopuses

    Science.gov (United States)

    Amor, Michael D.; Norman, Mark D.; Cameron, Hayley E.; Strugnell, Jan M.

    2014-01-01

    Despite extensive revisions over recent decades, the taxonomy of benthic octopuses (Family Octopodidae) remains in a considerable flux. Among groups of unresolved status is a species complex of morphologically similar shallow-water octopods from subtropical Australasia, including: Allopatric populations of Octopus tetricus on the eastern and western coasts of Australia, of which the Western Australian form is speculated to be a distinct or sub-species; and Octopus gibbsi from New Zealand, a proposed synonym of Australian forms. This study employed a combination of molecular and morphological techniques to resolve the taxonomic status of the ‘tetricus complex’. Phylogenetic analyses (based on five mitochondrial genes: 12S rRNA, 16S rRNA, COI, COIII and Cytb) and Generalised Mixed Yule Coalescent (GMYC) analysis (based on COI, COIII and Cytb) distinguished eastern and Western Australian O. tetricus as distinct species, while O. gibbsi was found to be synonymous with the east Australian form (BS = >97, PP = 1; GMYC p = 0.01). Discrete morphological differences in mature male octopuses (based on sixteen morphological traits) provided further evidence of cryptic speciation between east (including New Zealand) and west coast populations; although females proved less useful in morphological distinction among members of the tetricus complex. In addition, phylogenetic analyses suggested populations of octopuses currently treated under the name Octopus vulgaris are paraphyletic; providing evidence of cryptic speciation among global populations of O. vulgaris, the most commercially valuable octopus species worldwide. PMID:24964133

  17. Social complexity parallels vocal complexity: a comparison of three non-human primate species.

    Science.gov (United States)

    Bouchet, Hélène; Blois-Heulin, Catherine; Lemasson, Alban

    2013-01-01

    Social factors play a key role in the structuring of vocal repertoires at the individual level, notably in non-human primates. Some authors suggested that, at the species level too, social life may have driven the evolution of communicative complexity, but this has rarely been empirically tested. Here, we use a comparative approach to address this issue. We investigated vocal variability, at both the call type and the repertoire levels, in three forest-dwelling species of Cercopithecinae presenting striking differences in their social systems, in terms of social organization as well as social structure. We collected female call recordings from twelve De Brazza's monkeys (Cercopithecus neglectus), six Campbell's monkeys (Cercopithecus campbelli) and seven red-capped mangabeys (Cercocebus torquatus) housed in similar conditions. First, we noted that the level of acoustic variability and individual distinctiveness found in several call types was related to their importance in social functioning. Contact calls, essential to intra-group cohesion, were the most individually distinctive regardless of the species, while threat calls were more structurally variable in mangabeys, the most "despotic" of our three species. Second, we found a parallel between the degree of complexity of the species' social structure and the size, diversity, and usage of its vocal repertoire. Mangabeys (most complex social structure) called twice as often as guenons and displayed the largest and most complex repertoire. De Brazza's monkeys (simplest social structure) displayed the smallest and simplest repertoire. Campbell's monkeys displayed an intermediate pattern. Providing evidence of higher levels of vocal variability in species presenting a more complex social system, our results are in line with the theory of a social-vocal coevolution of communicative abilities, opening new perspectives for comparative research on the evolution of communication systems in different animal taxa.

  18. How phytohormones shape interactions between plants and the soil-borne fungus Fusarium oxysporum

    Directory of Open Access Journals (Sweden)

    Xiaotang eDi

    2016-02-01

    Full Text Available Plants interact with a huge variety of soil microbes, ranging from pathogenic to mutualistic. The Fusarium oxysporum (Fo species complex consists of ubiquitous soil inhabiting fungi that can infect and cause disease in over 120 different plant species including tomato, banana, cotton and Arabidopsis. However, in many cases Fo colonization remains symptomless or even has beneficial effects on plant growth and/or stress tolerance. Also in pathogenic interactions a lengthy asymptomatic phase usually precedes disease development. All this indicates a sophisticated and fine-tuned interaction between Fo and its host. The molecular mechanisms underlying this balance are poorly understood. Plant hormone signaling networks emerge as key regulators of plant-microbe interactions in general. In this review we summarize the effects of the major phytohormones on the interaction between Fo and its diverse hosts. Generally, Salicylic Acid (SA signaling reduces plant susceptibility, whereas Jasmonic Acid (JA, Ethylene (ET, Abscisic Acid (ABA and auxin have complex effects, and are potentially hijacked by Fo for host manipulation. Finally, we discuss how plant hormones and Fo effectors balance the interaction from beneficial to pathogenic and vice versa.

  19. Cephalosporium maydis is a distinct species in the Gaeumannomyces-Harpophora species complex.

    Science.gov (United States)

    Saleh, Amgad A; Leslie, John F

    2004-01-01

    Cephalosporium maydis is an important plant pathogen whose phylogenetic position relative to other fungi has not been established clearly. We compared strains of C. maydis, strains from several other plant-pathogenic Cephalosporium spp. and several possible relatives within the Gaeumannomyces-Harpophora species complex, to which C. maydis has been suggested to belong based on previous preliminary DNA sequence analyses. DNA sequences of the nuclear genes encoding the rDNA ITS region, β-tubulin, histone H3, and MAT-2 support the hypothesis that C. maydis is a distinct taxon within the Gaeumannomyces-Harpophora species complex. Based on amplified fragment length polymorphism (AFLP) profiles, C. maydis also is distinct from the other tested species of Cephalosporium, Phialophora sensu lato and members of Gaeumannomyces-Harpophora species complex, which supports its classification as Harpophora maydis. Oligonucleotide primers for H. maydis were developed that can be used in a PCR diagnostic protocol to rapidly and reliably detect and identify this pathogen. These diagnostic PCR primers will aid the detection of H. maydis in diseased maize because this fungus can be difficult to detect and isolate, and the movement of authentic cultures may be limited by quarantine restrictions.

  20. Exotic plant species around Jeongeup Research Complex and RFT industrial complex

    International Nuclear Information System (INIS)

    Kim, Jin Kyu; Cha, Min Kyoung; Ryu, Tae Ho; Lee, Yun Jong; Kim, Jin Hong

    2015-01-01

    In Shinjeong-dong of Jeongeup, there are three government-supported research institutes and an RFT industrial complex which is currently being established. Increased human activities can affect flora and fauna as a man-made pressure onto the region. As a baseline study, status of exotic plants was investigated prior to a full operation of the RFT industrial complex. A total of 54 species and 1 variety of naturalized or introduced plants were found in the study area. Among them, three species (Ambrosia artemisifolia var. elatior, Rumex acetocella and Aster pilosus) belong to 'nuisance species', and four species (Phytolacca americana, Iopomoea hederacea, Ereechtites hieracifolia and Rudbeckia laciniata) to ‘monitor species’ designated by the ministry of Environment. Some of naturalized trees and plants were intentionally introduced in this area, while others naturally immigrated. Physalis angulata seems to immigrate in the study area in the form of mixture with animal feeds as its distribution coincided with the transportation route of the animal feeds. Liquidambar styraciflua is amenable to the ecological investigation on the possible expansion of the species to the nearby Naejang National Park as its leave shape and autumn color are very similar to those of maple trees. The number of naturalized plants around the RFT industrial complex will increase with an increase in floating population, in human activities in association with constructions of factories and operations of the complex. The result of this study provides baseline data for assessing the ecological change of the region according to the operation of the RFT industrial complex

  1. Social complexity parallels vocal complexity: a comparison of three nonhuman primate species

    Directory of Open Access Journals (Sweden)

    Hélène eBOUCHET

    2013-07-01

    Full Text Available Social factors play a key role in the structuring of vocal repertoires at the individual level, notably in nonhuman primates. Some authors suggested that, at the species level too, social life may have driven the evolution of communicative complexity, but this has rarely been empirically tested. Here, we use a comparative approach to address this issue. We investigated vocal variability, at both the call type and the repertoire levels, in three forest-dwelling species of Cercopithecinae presenting striking differences in their social systems, in terms of social organization as well as social structure. We collected female call recordings from twelve De Brazza’s monkeys (Cercopithecus neglectus, six Campbell’s monkeys (Cercopithecus campbelli and seven red-capped mangabeys (Cercocebus torquatus housed in similar conditions. First, we noted that the level of acoustic variability and individual distinctiveness found in several call types was related to their importance in social functioning. Contact calls, essential to intra-group cohesion, were the most individually distinctive regardless of the species, while threat calls were more structurally variable in mangabeys, the most ‘despotic’ of our three species. Second, we found a parallel between the degree of complexity of the species’ social structure and the size, diversity, and usage of its vocal repertoire. Mangabeys (most complex social structure called twice as often as guenons and displayed the largest and most complex repertoire. De Brazza’s monkeys (simplest social structure displayed the smallest and simplest repertoire. Campbell’s monkeys displayed an intermediate pattern. Providing evidence of higher levels of vocal variability in species presenting a more complex social system, our results are in line with the theory of a social-vocal coevolution of communicative abilities, opening new perspectives for comparative research on the evolution of communication systems in

  2. Exotic plant species around Jeongeup Research Complex and RFT industrial complex

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Kyu; Cha, Min Kyoung; Ryu, Tae Ho; Lee, Yun Jong; Kim, Jin Hong [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup(Korea, Republic of)

    2015-08-15

    In Shinjeong-dong of Jeongeup, there are three government-supported research institutes and an RFT industrial complex which is currently being established. Increased human activities can affect flora and fauna as a man-made pressure onto the region. As a baseline study, status of exotic plants was investigated prior to a full operation of the RFT industrial complex. A total of 54 species and 1 variety of naturalized or introduced plants were found in the study area. Among them, three species (Ambrosia artemisifolia var. elatior, Rumex acetocella and Aster pilosus) belong to 'nuisance species', and four species (Phytolacca americana, Iopomoea hederacea, Ereechtites hieracifolia and Rudbeckia laciniata) to ‘monitor species’ designated by the ministry of Environment. Some of naturalized trees and plants were intentionally introduced in this area, while others naturally immigrated. Physalis angulata seems to immigrate in the study area in the form of mixture with animal feeds as its distribution coincided with the transportation route of the animal feeds. Liquidambar styraciflua is amenable to the ecological investigation on the possible expansion of the species to the nearby Naejang National Park as its leave shape and autumn color are very similar to those of maple trees. The number of naturalized plants around the RFT industrial complex will increase with an increase in floating population, in human activities in association with constructions of factories and operations of the complex. The result of this study provides baseline data for assessing the ecological change of the region according to the operation of the RFT industrial complex.

  3. Inoculation methods and aggressiveness of five Fusarium species against peach palm

    Directory of Open Access Journals (Sweden)

    Tiago Miguel Jarek

    2018-04-01

    Full Text Available ABSTRACT: Fusarium wilt is a major disease which affects peach palm (Bactris gasipaes Kunth.var gasipaes Henderson. This study aimed to evaluate inoculation methods and aggressiveness of isolates of five Fusarium species on peach palm. Fusarium proliferatum can infect the leaves, stem, and roots of peach palm. F. proliferatum, F. oxysporum species complex (FOSC, F. verticillioides, F. solani species complex (FSSC, and Gibberella fujikuroi species complex (GFSC are pathogenic to peach palm. The use of Fusarium-colonized ground corn for root inoculation was effective and reduced the level of damage to plants.

  4. Delimiting Species Boundaries within a Paraphyletic Species Complex: Insights from Morphological, Genetic, and Molecular Data on Paramecium sonneborni (Paramecium aurelia species complex, Ciliophora, Protozoa).

    Science.gov (United States)

    Przyboś, Ewa; Tarcz, Sebastian; Rautian, Maria; Sawka, Natalia

    2015-09-01

    The demarcation of boundaries between protist species is often problematic because of the absence of a uniform species definition, the abundance of cryptic diversity, and the occurrence of convergent morphology. The ciliates belonging to the Paramecium aurelia complex, consisting of 15 species, are a good model for such systematic and evolutionary studies. One member of the complex is P. sonneborni, previously known only from one stand in Texas (USA), but recently found in two new sampling sites in Cyprus (creeks running to Salt Lake and Oroklini Lake near Larnaca). The studied Paramecium sonneborni strains (from the USA and Cyprus) reveal low viability in the F1 and F2 generations of interstrain hybrids and may be an example of ongoing allopatric speciation. Despite its molecular distinctiveness, we postulate that P. sonneborni should remain in the P. aurelia complex, making it a paraphyletic taxon. Morphological studies have revealed that some features of the nuclear apparatus of P. sonneborni correspond to the P. aurelia spp. complex, while others are similar to P. jenningsi and P. schewiakoffi. The observed discordance indicates rapid splitting of the P. aurelia-P. jenningsi-P. schewiakoffi group, in which genetic, morphological, and molecular boundaries between species are not congruent. Copyright © 2015 Elsevier GmbH. All rights reserved.

  5. The cell wall of Fusarium oxysporum

    NARCIS (Netherlands)

    Schoffelmeer, EAM; Klis, FM; Sietsma, JH; Cornelissen, BJC

    1999-01-01

    Sugar analysis of isolated cell walls from three formae speciales of Fusarium oxysporum showed that they contained not only glucose and (N-acetyl)-glucosamine, but also mannose, galactose, and uronic acids, presumably originating from cell wall glycoproteins. Cell wall glycoproteins accounted for

  6. Tissue culture of three species of Laurencia complex

    Science.gov (United States)

    Shen, Songdong; Wu, Xunjian; Yan, Binlun; He, Lihong

    2010-05-01

    To establish a micropropagation system of three Laurencia complex species ( Laurencia okamurai, Laurencia tristicha, and Chondrophycus undulatus) by tissue culture techniques, we studied the regeneration characteristics and optimal culture conditions of axenic algal fragments cultured on solid medium and in liquid medium. Regeneration structures were observed and counted regularly under a reverse microscope to investigate the regeneration process, polarity and optimal illumination, and temperature and salinity levels. The results show that in most cultures of the three species, we obtained bud regeneration on solidified medium with 0.5% agar and in liquid medium. Rhizoid-like regeneration was filamentous and developed from the lower cut surface of fragments in L. okamurai, but was discoid and developed from the apical back side of bud regeneration in L. tristicha and C. undulatus. Regeneration polarity was localized to the apical part of algal fronds in all three species, and on fragments cut from the basal part of algae buds could develop from both the upper and the lower cut surfaces. Buds could develop from both the medullary and the cortical portions in L. okamurai and C. undulatus, while in L. tristicha, buds only emerged from the cortex. The optimal culture conditions for L. okamurai were 4 500 lx, 20°C and 35 (salinity); for C. undulatus, 4 500 lx, 20°C and 30; and for L. tristicha, 4 500 lx, 25°C and 30.

  7. Identification of pathogenicity-related genes in Fusarium oxysporum f. sp. cepae.

    Science.gov (United States)

    Taylor, Andrew; Vágány, Viktória; Jackson, Alison C; Harrison, Richard J; Rainoni, Alessandro; Clarkson, John P

    2016-09-01

    Pathogenic isolates of Fusarium oxysporum, distinguished as formae speciales (f. spp.) on the basis of their host specificity, cause crown rots, root rots and vascular wilts on many important crops worldwide. Fusarium oxysporum f. sp. cepae (FOC) is particularly problematic to onion growers worldwide and is increasing in prevalence in the UK. We characterized 31 F. oxysporum isolates collected from UK onions using pathogenicity tests, sequencing of housekeeping genes and identification of effectors. In onion seedling and bulb tests, 21 isolates were pathogenic and 10 were non-pathogenic. The molecular characterization of these isolates, and 21 additional isolates comprising other f. spp. and different Fusarium species, was carried out by sequencing three housekeeping genes. A concatenated tree separated the F. oxysporum isolates into six clades, but did not distinguish between pathogenic and non-pathogenic isolates. Ten putative effectors were identified within FOC, including seven Secreted In Xylem (SIX) genes first reported in F. oxysporum f. sp. lycopersici. Two highly homologous proteins with signal peptides and RxLR motifs (CRX1/CRX2) and a gene with no previously characterized domains (C5) were also identified. The presence/absence of nine of these genes was strongly related to pathogenicity against onion and all were shown to be expressed in planta. Different SIX gene complements were identified in other f. spp., but none were identified in three other Fusarium species from onion. Although the FOC SIX genes had a high level of homology with other f. spp., there were clear differences in sequences which were unique to FOC, whereas CRX1 and C5 genes appear to be largely FOC specific. © 2015 The Authors Molecular Plant Pathology Published by British Society for Plant Pathology and John Wiley & Sons Ltd.

  8. Identification of pathogenicity‐related genes in Fusarium oxysporum f. sp. cepae

    Science.gov (United States)

    Vágány, Viktória; Jackson, Alison C.; Harrison, Richard J.; Rainoni, Alessandro; Clarkson, John P.

    2016-01-01

    Summary Pathogenic isolates of Fusarium oxysporum, distinguished as formae speciales (f. spp.) on the basis of their host specificity, cause crown rots, root rots and vascular wilts on many important crops worldwide. Fusarium oxysporum f. sp. cepae (FOC) is particularly problematic to onion growers worldwide and is increasing in prevalence in the UK. We characterized 31 F. oxysporum isolates collected from UK onions using pathogenicity tests, sequencing of housekeeping genes and identification of effectors. In onion seedling and bulb tests, 21 isolates were pathogenic and 10 were non‐pathogenic. The molecular characterization of these isolates, and 21 additional isolates comprising other f. spp. and different Fusarium species, was carried out by sequencing three housekeeping genes. A concatenated tree separated the F. oxysporum isolates into six clades, but did not distinguish between pathogenic and non‐pathogenic isolates. Ten putative effectors were identified within FOC, including seven Secreted In Xylem (SIX) genes first reported in F. oxysporum f. sp. lycopersici. Two highly homologous proteins with signal peptides and RxLR motifs (CRX1/CRX2) and a gene with no previously characterized domains (C5) were also identified. The presence/absence of nine of these genes was strongly related to pathogenicity against onion and all were shown to be expressed in planta. Different SIX gene complements were identified in other f. spp., but none were identified in three other Fusarium species from onion. Although the FOC SIX genes had a high level of homology with other f. spp., there were clear differences in sequences which were unique to FOC, whereas CRX1 and C5 genes appear to be largely FOC specific. PMID:26609905

  9. Plant defense response against Fusarium oxysporum and strategies to develop tolerant genotypes in banana.

    Science.gov (United States)

    Swarupa, V; Ravishankar, K V; Rekha, A

    2014-04-01

    Soil-borne fungal pathogen, Fusarium oxysporum causes major economic losses by inducing necrosis and wilting symptoms in many crop plants. Management of fusarium wilt is achieved mainly by the use of chemical fungicides which affect the soil health and their efficiency is often limited by pathogenic variability. Hence understanding the nature of interaction between pathogen and host may help to select and improve better cultivars. Current research evidences highlight the role of oxidative burst and antioxidant enzymes indicating that ROS act as an important signaling molecule in banana defense response against Fusarium oxysporum f.sp. cubense. The role of jasmonic acid signaling in plant defense against necrotrophic pathogens is well recognized. But recent studies show that the role of salicylic acid is complex and ambiguous against necrotrophic pathogens like Fusarium oxysporum, leading to many intriguing questions about its relationship between other signaling compounds. In case of banana, a major challenge is to identify specific receptors for effector proteins like SIX proteins and also the components of various signal transduction pathways. Significant progress has been made to uncover the role of defense genes but is limited to only model plants such as Arabidopsis and tomato. Keeping this in view, we review the host response, pathogen diversity, current understanding of biochemical and molecular changes that occur during host and pathogen interaction. Developing resistant cultivars through mutation, breeding, transgenic and cisgenic approaches have been discussed. This would help us to understand host defenses against Fusarium oxysporum and to formulate strategies to develop tolerant cultivars.

  10. Comparative studies with regard to the influence of carbon and nitrogen ratio on sporulation in Fusarium oxysporum and Fusarium moniliforme v. subglutinans.

    Science.gov (United States)

    Prasad, M

    1979-01-01

    Carbon/nitrogen ratio as a factor for sporulation, expressed in terms of magnitude of population variation of macroconidia and microconidia in the cultures of Eusarium oxysporum Schlecht ex. Fr., Fusarium moniliforme v. subglutinans Wr. and Rg., and of chlamydospores (only in Fusarium oxysporum) was investigated. It has been found that the amount of carbon source shapes the course of macro- and micro. conidial production in a linear fashion, being enhanced parallel to the increase in its amount-Nitrogen level, limiting proliferation and effectively diminishing the macro- and micro-conidial population, varies for the two species, namely Fusarium oxysporum and Fusarium moniliforme v-subglutinans. For chlamydomspore production, higher carbon and still higher nitrogen concentration favours profuse proliferation in case of Fusarium oxysporum.

  11. Morphological and molecular characterization of Fusarium. solani and F. oxysporum associated with crown disease of oil palm.

    Science.gov (United States)

    Hafizi, R; Salleh, B; Latiffah, Z

    2013-01-01

    Crown disease (CD) is infecting oil palm in the early stages of the crop development. Previous studies showed that Fusarium species were commonly associated with CD. However, the identity of the species has not been resolved. This study was carried out to identify and characterize through morphological approaches and to determine the genetic diversity of the Fusarium species. 51 isolates (39%) of Fusarium solani and 40 isolates (31%) of Fusarium oxysporum were recovered from oil palm with typical CD symptoms collected from nine states in Malaysia, together with samples from Padang and Medan, Indonesia. Based on morphological characteristics, isolates in both Fusarium species were classified into two distinct morphotypes; Morphotypes I and II. Molecular characterization based on IGS-RFLP analysis produced 27 haplotypes among the F. solani isolates and 33 haplotypes for F. oxysporum isolates, which indicated high levels of intraspecific variations. From UPGMA cluster analysis, the isolates in both Fusarium species were divided into two main clusters with the percentage of similarity from 87% to 100% for F. solani, and 89% to 100% for F. oxysporum isolates, which was in accordance with the Morphotypes I and II. The results of the present study indicated that F. solani and F. oxysporum associated with CD of oil palm in Malaysia and Indonesia were highly variable.

  12. The intercropping partner affects arbuscular mycorrhizal fungi and Fusarium oxysporum f. sp. lycopersici interactions in tomato.

    Science.gov (United States)

    Hage-Ahmed, Karin; Krammer, Johannes; Steinkellner, Siegrid

    2013-10-01

    Arbuscular mycorrhizal fungi (AMF) and their bioprotective aspects are of great interest in the context of sustainable agriculture. Combining the benefits of AMF with the utilisation of plant species diversity shows great promise for the management of plant diseases in environmentally compatible agriculture. In the present study, AMF were tested against Fusarium oxysporum f. sp. lycopersici with tomato intercropped with either leek, cucumber, basil, fennel or tomato itself. Arbuscular mycorrhizal (AM) root colonisation of tomato was clearly affected by its intercropping partners. Tomato intercropped with leek showed even a 20 % higher AM colonisation rate than tomato intercropped with tomato. Positive effects of AMF expressed as an increase of tomato biomass compared to the untreated control treatment could be observed in root as well as in shoot weights. A compensation of negative effects of F. oxysporum f. sp. lycopersici on tomato biomass by AMF was observed in the tomato/leek combination. The intercropping partners leek, cucumber, basil and tomato had no effect on F. oxysporum f. sp. lycopersici disease incidence or disease severity indicating no allelopathic suppression; however, tomato co-cultivated with tomato clearly showed a negative effect on one plant/pot with regard to biomass and disease severity of F. oxysporum f. sp. lycopersici. Nonetheless, bioprotective effects of AMF resulting in the decrease of F. oxysporum f. sp. lycopersici disease severity were evident in treatments with AMF and F. oxysporum f. sp. lycopersici co-inoculation. However, these bioprotective effects depended on the intercropping partner since these effects were only observed in the tomato/leek and tomato/basil combination and for the better developed plant of tomato/tomato. In conclusion, the effects of the intercropping partner on AMF colonisation of tomato are of great interest for crop plant communities and for the influences on each other. The outcome of the bioprotective

  13. Effector Gene Suites in Some Soil Isolates of Fusarium oxysporum Are Not Sufficient Predictors of Vascular Wilt in Tomato.

    Science.gov (United States)

    Jelinski, Nicolas A; Broz, Karen; Jonkers, Wilfried; Ma, Li-Jun; Kistler, H Corby

    2017-07-01

    Seventy-four Fusarium oxysporum soil isolates were assayed for known effector genes present in an F. oxysporum f. sp. lycopersici race 3 tomato wilt strain (FOL MN-25) obtained from the same fields in Manatee County, Florida. Based on the presence or absence of these genes, four haplotypes were defined, two of which represented 96% of the surveyed isolates. These two most common effector haplotypes contained either all or none of the assayed race 3 effector genes. We hypothesized that soil isolates with all surveyed effector genes, similar to FOL MN-25, would be pathogenic toward tomato, whereas isolates lacking all effectors would be nonpathogenic. However, inoculation experiments revealed that presence of the effector genes alone was not sufficient to ensure pathogenicity on tomato. Interestingly, a nonpathogenic isolate containing the full suite of unmutated effector genes (FOS 4-4) appears to have undergone a chromosomal rearrangement yet remains vegetatively compatible with FOL MN-25. These observations confirm the highly dynamic nature of the F. oxysporum genome and support the conclusion that pathogenesis among free-living populations of F. oxysporum is a complex process. Therefore, the presence of effector genes alone may not be an accurate predictor of pathogenicity among soil isolates of F. oxysporum.

  14. Media for efficient generating nitrate- - nonutilizing (NIT) mutants of Verticillium dahliae, Colletotrichum gloeosporioides, Colletotrichum lindemuthianum and Fusarium oxysporum.

    NARCIS (Netherlands)

    Rataj-Guranowska, M.; Pieczul, K.; Nowak, E.; Hiemstra, J.A.; Drapikowska, M.

    2001-01-01

    The effect of several media amended wit potassium chlorate (1.5% and 6%) on generation of nit mutants, especially nit M mutants from Verticillium dahliae, Colletotrichum gloeosporioides, Colletotrichum lindemuthianum and Fusarium oxysporum were studied. For all species minimal medium with 6%

  15. The Complex Conductivity Signature of Geobacter Species in Geological Media

    Science.gov (United States)

    Brown, I.; Atekwana, E. A.; Sarkisova, S.; Achang, M.

    2013-12-01

    The Complex Conductivity (CC) technique is a promising biogeophysical approach for sensing microbially-induced changes in geological media because of its low-invasive character and sufficient sensitivity to enhanced microbial activity in the near subsurface. Geobacter species have been shown to play important roles in the bioremediation of groundwater contaminated with petroleum and landfill leachate. This capability is based on the ability of Geobacter species to reduce Fe(III) by transferring of electrons from the reduced equivalents to Fe(III) rich minerals through respiration chain and special metallic-like conductors - pili. Only the cultivation of Geobacter species on Fe(III) oxides specifically express pili biosynthesis. Moreover, mutants that cannot produce pili are unable to reduce Fe(III) oxides. However, little is known about the contribution of these molecular conductors (nanowires) to the generation of complex conductivity signatures in geological media. Here, we present the results about the modulation of CC signatures in geological media by Geobacter sulfurreducens (G.s.). Cultures of wild strain G.s. and its pilA(-) mutant were anaerobically cultivated in the presence of the pair of such donors and acceptors of electrons: acetate - fumarate, and acetate - magnetite under anaerobic conditions. Each culture was injected in CC sample holders filled either with N2-CO2 mix (planktonic variant) or with this gases mix and glass beads, d=1 mm, (porous medium variant). Both strains of G.s. proliferated well in a medium supplemented with acetate-fumarate. However, pilA(-) mutant did not multiply in a medium supplemented with ox-red pair yeast extract - magnetite. This observation confirmed that only wild pilA(+) strain is capable of the dissimilatory reduction of Fe(III) within magnetite molecule. The measurement of CC responses from planktonic culture of G.s. wild strain grown with acetate-fumarate did not show linear correlation with their magnitudes but

  16. Biological control of Orobanche aegyptiaca by Fusarium oxysporum F. sp. Orobanchein northwest Iran.

    Science.gov (United States)

    Saremi, H; Okhovvat, S M

    2008-01-01

    Broomrape (Orobanche aegyptiaca) is one of the most serious weed pathogen on many plants all over the world, especially in northwest Iran. It causes damage on some plants particularly on tomato, cucumber and other dicotyledonous crops in zanjan province. Broomrape as weed, caused reductions in crop yield, adversely affected crop quality, and resulted in loss of cultivated land due to reduced crop alternatives. Since there were no any chemical methods and other proper technique to control this plant parasite we tried to find a good mechanism for its management in the fields. Our study showed there was a specific species, Fusarium oxysporum f. sp. orobonche that had infected Broomrapes naturally in the field. In point of fact the species was isolated from naturally infected Broomrape in studied Locations. Our surveys showed F. oxysporum f. sp. orobanche caused disease on orobanche spp. in different agricultural fields. Although there were other fungal species which can nearly manage the orobanche but it can be fungal pathogen to other plants. However the best fungal isolate can be F. oxysporum f. sp. orobanche since it may not be pathogen for other plants.

  17. The Tetramorium tortuosum species group (Hymenoptera, Formicidae, Myrmicinae revisited - taxonomic revision of the Afrotropical T. capillosum species complex

    Directory of Open Access Journals (Sweden)

    Francisco Hita Garcia

    2013-05-01

    Full Text Available In this study we revise the taxonomy of the Tetramorium tortuosum species group members encountered in the Afrotropical region, which we have placed in its own subgroup: the T. capillosum species complex. We re-describe the two previously known species T. capillosum Bolton and T. tabarum Bolton, and describe the new species T. hecate sp. n. The geographic distribution of the three species appears to be restricted to the equatorial rainforests of Central Africa. We provide a diagnosis of the T. capillosum species complex, an illustrated identification key to species level, and worker-based species descriptions, which include diagnoses, discussions, high-quality montage images, and distribution maps. Furthermore, we discuss biogeography and composition of the globally distributed T. tortuosum group.

  18. Fusarium dimerum Species Complex (Fusarium penzigii) Keratitis After Corneal Trauma.

    Science.gov (United States)

    do Carmo, Anália; Costa, Esmeralda; Marques, Marco; Quadrado, Maria João; Tomé, Rui

    2016-12-01

    We report a case of a keratitis associated with a Fusarium penzigii-a Fusarium dimerum species complex (FDSC)-in a 81-year-old woman after a corneal trauma with a tree branch. At patient admittance, slit lamp biomicroscopy revealed an exuberant chemosis, an inferior corneal ulcer with an associated inflammatory infiltrate, a central corneal abscess, bullous keratopathy and posterior synechiae. Corneal scrapes were obtained for identification of bacteria and fungi, and the patient started antibiotic treatment on empirical basis. Few days later, the situation worsened with the development of hypopyon. By that time, Fusarium was identified in cultures obtained from corneal scrapes and the patient started topical amphotericin B 0.15 %. Upon the morphological identification of the Fusarium as a FDSC, and since there was no clinical improvement, the treatment with amphotericin B was suspended and the patient started voriconazole 10 mg/ml, eye drops, hourly and voriconazole 200 mg iv, every 12 h for 1 month. The hypopyon resolved and the inflammatory infiltrate improved, but the abscess persisted at the last follow-up visit. The molecular identification revealed that the FDSC was a F. penzigii.

  19. Multifaceted roles of metabolic enzymes of the Paracoccidioides species complex

    Directory of Open Access Journals (Sweden)

    Caroline Maria Marcos

    2014-12-01

    Full Text Available Paracoccidioides species are dimorphic fungi, and are the etiologic agents of paracoccidioidomycosis (PCM, a serious disease of multiple organs. The large number of tissues colonized by this fungus suggests the presence of a variety of surface molecules involved in adhesion. A surprising finding is that the majority of enzymes in the glycolytic pathway, tricarboxylic acid (TCA cycle and glyoxylate cycle in Paracoccidioides spp. has adhesive properties that aid in the interaction with the host extracellular matrix, and so act as ‘moonlighting’ proteins. Moonlighting proteins have multiple functions and add another dimension to cellular complexity, while benefiting cells in several ways. This phenomenon occurs in both eukaryotes and prokaryotes. For example, moonlighting proteins from the glycolytic pathway or TCA cycle can play roles in bacterial pathogens, either by acting as proteins secreted in a conventional pathway or not and/or as cell surface component that facilitate adhesion or adherence . This review outlines the multifuncionality exposed by a variety of Paracoccidioides spp. enzymes including aconitase, aldolase, glyceraldehyde-3-phosphate dehydrogenase, isocitrate lyase, malate synthase, triose phosphate isomerase, fumarase and enolase. The roles that moonlighting activities play in the virulence characteristics of this fungus and several other human pathogens during their interactions with the host are discussed.

  20. MEDIATOR18 and MEDIATOR20 confer susceptibility to Fusarium oxysporum in Arabidopsis thaliana

    OpenAIRE

    Fallath, Thorya; Kidd, Brendan N.; Stiller, Jiri; Davoine, Celine; Bj?rklund, Stefan; Manners, John M.; Kazan, Kemal; Schenk, Peer M.

    2017-01-01

    The conserved protein complex known as Mediator conveys transcriptional signals by acting as an intermediary between transcription factors and RNA polymerase II. As a result, Mediator subunits play multiple roles in regulating developmental as well as abiotic and biotic stress pathways. In this report we identify the head domain subunits MEDIATOR18 and MEDIATOR20 as important susceptibility factors for Fusarium oxysporum infection in Arabidopsis thaliana. Mutants of MED18 and MED20 display do...

  1. Detection of Fusarium oxysporum f.sp. basilici in substrates and roots by PCR.

    Science.gov (United States)

    Pugliese, M; Ferrocino, I; Gullino, M L; Garibaldi, A

    2013-01-01

    Fusarium oxysporum is a soil-borne fungus that causes vascular wilts in a wide variety of plant species. Basil is recognized as an ecological niche for Fusarium oxysporum f.sp. basilici (FOB) and this fungus is now present in most countries where basil is cultivated. The rapid identification of the species affecting basil plants is necessary to define a successful method for crop protection. The aim of this study was to develop a PCR method for the rapid detection of Fusarium oxysporum f. sp. basilici in substrates. The specificity of the primers used was tested using the DNA extracted directly from substrate samples. Fusarium oxysporum f.sp. basilici was artificially inoculated with decreasing amounts in a commercial substrate (sphagnum peat moss) and in a mixture with 40% of municipal compost, after steam disinfestation. Basil seeds (cv. Fine verde) were sown in pots that were laid on a bench in the greenhouse. At time 0 and after 7, 14 and 21 days from the inoculation, substrate and root samples were collected and prepared for microbial analysis and for the DNA extraction. DNA extraction was carried out using NucleoSpin Soil Kit (Macherey-Nagel, Germany). PCR amplification for the specific detection was carried out using primer sets Bik 1 (5'-ATT CAA GAG CTA AAG GTC C-3') and Bik 4 (5'-TTT GAC CAA GAT AGA TGC C-3') for the first PCR, while primers Bik 1 + Bik 2 (5'-AAA GGT AGT ATA TCG GAG G-3') for the nested PCR to increase detection sensitivity. Disease incidence was also assessed 21 days after seeding. The results showed the presence of amplified fragments of the expected size when the concentration of F. oxysporum f.sp. basilici was at least 3.5 Log CFU g(-1) by using DNA extract directly from substrate, before roots were infected by the pathogen. The detection of Fusarium oxysporum f. sp. basilici by PCR method developed in this study is certainly simple and fast and can be useful for its reliable detection in substrate samples, but not to guarantee that

  2. Four new species of Pyropia (Bangiales, Rhodophyta) from the west coast of North America: the Pyropialanceolata species complex updated.

    Science.gov (United States)

    Lindstrom, Sandra C; Hughey, Jeffery R; Rosas, Luis E Aguilar

    2015-01-01

    Recent molecular studies indicate that the Pyropialanceolata species complex on the west coast of North America is more speciose than previously thought. Based on extensive rbcL gene sequencing of representative specimens we recognize seven species in the complex, three of which are newly described: Pyropiamontereyensis sp. nov., Pyropiacolumbiensis sp. nov., and Pyropiaprotolanceolata sp. nov. The new species are all lanceolate, at least when young, and occur in the upper mid to high intertidal zone primarily in winter and early spring. Pyropiamontereyensis and Pyropiacolumbiensis are sister taxa that are distributed south and north of Cape Mendocino, respectively, and both occur slightly lower on the shore than Pyropialanceolata or Pyropiapseudolanceolata. Pyropiaprotolanceolata is known thus far only from Morro Rock and the Monterey Peninsula, California; it occurs basally to the other species in the complex in the molecular phylogeny. A fourth newly described species, Pyropiabajacaliforniensis sp. nov., is more closely related to Pyropianereocystis than to species in this complex proper. It is a thin species with undulate margins known only from Moss Landing, Monterey Bay, California, and northern Baja California; it also occurs in the high intertidal in spring. Porphyramumfordii, a high intertidal winter species that has frequently been confused with species in the Pyropialanceolata complex, has now been confirmed to occur from Calvert Island, British Columbia, to Pescadero State Park, California.

  3. Four new species of Pyropia (Bangiales, Rhodophyta from the west coast of North America: the Pyropia lanceolata species complex updated

    Directory of Open Access Journals (Sweden)

    Sandra C. Lindstrom

    2015-06-01

    Full Text Available Recent molecular studies indicate that the Pyropia lanceolata species complex on the west coast of North America is more speciose than previously thought. Based on extensive rbcL gene sequencing of representative specimens we recognize seven species in the complex, three of which are newly described: Py. montereyensis sp. nov., Py. columbiensis sp. nov., and Py. protolanceolata sp. nov. The new species are all lanceolate, at least when young, and occur in the upper mid to high intertidal zone primarily in winter and early spring. Pyropia montereyensis and Py. columbiensis are sister taxa that are distributed south and north of Cape Mendocino, respectively, and both occur slightly lower on the shore than Py. lanceolata or Py. pseudolanceolata. Pyropia protolanceolata is known thus far only from Morro Rock and the Monterey Peninsula, California; it occurs basally to the other species in the complex in the molecular phylogeny. A fourth newly described species, Pyropia bajacaliforniensis sp. nov., is more closely related to Py. nereocystis than to species in this complex proper. It is a thin species with undulate margins known only from Moss Landing, Monterey Bay, California, and northern Baja California; it also occurs in the high intertidal in spring. Porphyra mumfordii, a high intertidal winter species that has frequently been confused with species in the Py. lanceolata complex, has now been confirmed to occur from Calvert Island, British Columbia, to Pescadero State Park, California.

  4. Fermentation characteristics of Fusarium oxysporum grown on acetate

    DEFF Research Database (Denmark)

    Panagiotou, Gianni; Pachidou, Fotini; Petroutsos, Dimitris

    2008-01-01

    In this study, the growth characteristics of Fusarium oxysporum were evaluated in minimal medium using acetate or different mixtures of acetate and glucose as carbon source. The minimum inhibitory concentration (MIC) of acetic acid that F oxysporum cells could tolerate was 0.8% w/v while glucose ...

  5. Complex patterns of speciation in cosmopolitan "rock posy" lichens--discovering and delimiting cryptic fungal species in the lichen-forming Rhizoplaca melanophthalma species-complex (Lecanoraceae, Ascomycota).

    Science.gov (United States)

    Leavitt, Steven D; Fankhauser, Johnathon D; Leavitt, Dean H; Porter, Lyndon D; Johnson, Leigh A; St Clair, Larry L

    2011-06-01

    A growing body of evidence indicates that in some cases morphology-based species circumscription of lichenized fungi misrepresents the number of existing species. The cosmopolitan "rock posy" lichen (Rhizoplaca melanophthalma) species-complex includes a number of morphologically distinct species that are both geographically and ecologically widespread, providing a model system to evaluate speciation in lichen-forming ascomycetes. In this study, we assembled multiple lines of evidence from nuclear DNA sequence data, morphology, and biochemistry for species delimitation in the R. melanophthalma species-complex. We identify a total of ten candidate species in this study, four of which were previously recognized as distinct taxa and six previously unrecognized lineages found within what has been thus far considered a single species. Candidate species are supported using inferences from multiple empirical operational criteria. Multiple instances of sympatry support the view that these lineages merit recognition as distinct taxa. Generally, we found little corroboration between morphological and chemical characters, and previously unidentified lineages were morphologically polymorphic. However, secondary metabolite data supported one cryptic saxicolous lineage, characterized by orsellinic-derived gyrophoric and lecanoric acids, which we consider to be taxonomically significant. Our study of the R. melanophthalma species-complex indicates that the genus Rhizoplaca, as presently circumscribed, is more diverse in western North American than originally perceived, and we present our analyses as a working example of species delimitation in morphologically cryptic and recently diverged lichenized fungi. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. An analysis of species boundaries and biogeographic patterns in a cryptic species complex: the rotifer--Brachionus plicatilis.

    Science.gov (United States)

    Suatoni, Elizabeth; Vicario, Saverio; Rice, Sean; Snell, Terry; Caccone, Adalgisa

    2006-10-01

    Since the advent of molecular phylogenetics, there is increasing evidence that many small aquatic and marine invertebrates--once believed to be single, cosmopolitan species--are in fact cryptic species complexes. Although the application of the biological species concept is central to the identification of species boundaries in these cryptic complexes, tests of reproductive isolation do not frequently accompany phylogenetic studies. Because different species concepts generally identify different boundaries in cryptic complexes, studies that apply multiple species concepts are needed to gain a more detailed understanding of patterns of diversification in these taxa. Here we explore different methods of empirically delimiting species boundaries in the salt water rotifer Brachionus plicatilis by comparing reproductive data (i.e., the traditional biological species concept) to phylogenetic data (the genealogical species concept). Based on a high degree of molecular sequence divergence and largely concordant genetic patterns in COI and ITS1, the genealogical species hypothesis indicates the existence of at least 14 species--the highest estimate for the group thus far. A test of the genealogical species concept with biological crosses shows a fairly high level of concordance, depending on the degree of reproductive success used to draw boundaries. The convergence of species concepts in this group suggests that many of the species within the group may be old. Although the diversity of the group is higher than previously understood, geographic distributions remain broad. Efficient passive dispersal has resulted in global distributions for many species with some evidence of isolation by distance over large geographic scales. These patterns concur with expectations that micro-meiofauna (0.1-1mm) have biogeographies intermediate to microbial organisms and large vertebrates. Sympatry of genetically distant strains is common.

  7. Double keystone bird in a keystone species complex.

    OpenAIRE

    Daily, G C; Ehrlich, P R; Haddad, N M

    1993-01-01

    Species in a Colorado subalpine ecosystem show subtle interdependences. Red-naped sapsuckers play two distinct keystone roles. They excavate nest cavities in fungus-infected aspens that are required as nest sites by two species of swallows, and they drill sap wells into willows that provide abundant nourishment for themselves, hummingbirds, orange-crowned warblers, chipmunks, and an array of other sap robbers. The swallows thus depend on, and the sap robbers benefit from, a keystone species c...

  8. Species composition of and fumonisin production by the Fusarium fujikuroi species complex isolated from Korean cereals.

    Science.gov (United States)

    Choi, Jung-Hye; Lee, Seolhee; Nah, Ju-Young; Kim, Hee-Kyoung; Paek, Ji-Seon; Lee, Soohyung; Ham, Hyeonheui; Hong, Sung Kee; Yun, Sung-Hwan; Lee, Theresa

    2018-02-21

    To assess the risk of fumonisin contamination in Korean cereals, we isolated colonies of the Fusarium fujikuroi species complex (FFSC) from barley, maize, rice and soybean samples from 2011 to 2015. A total of 878 FFSC strains were isolated mostly from maize and rice, and species identity of the isolates were determined using the DNA sequence of the translation elongation factor 1-α (TEF-1α) and RNA polymerase II (RPB2) genes. Fusaria recovered from Korean cereals included F. fujikuroi (317 isolates and a frequency of 36%), F. proliferatum (212 isolates and 24.1%), F. verticillioides (170 isolates and 19.4%), F. concentricum (86 strains and 9.8%), F. andiyazi (56 isolates and 6.4%), F. subglutinans (28 isolates and 3.2%), F. thapsinum (5 isolates and 0.6%), and F. circinatum (2 isolates and 0.2%). The rice samples were dominated by F. fujikuroi (47.4%), F. proliferatum (27.3%), and F. concentricum (15.1%), whereas maize samples were dominated by F. verticillioides (33.9%), F. fujikuroi (25.3%), and F. proliferatum (21.1%). A phylogenetic analysis of 70 representative isolates demonstrated that each species was resolved as genealogically exclusive in the ML tree. Fumonisin production potential was evaluated using a PCR assay for the fumonisin biosynthesis gene, FUM1 in all of the isolates. Most of the isolates tested (94%) were positive for FUM1. All of the isolates assigned to F. fujikuroi, F. proliferatum, F. verticillioides and F. thapsinum were positive for FUM1 irrespective of their host origin. Seventy-seven representative isolates positive for FUM1 were examined for fumonisin production in rice medium. The majority of F. proliferatum (26/27, 96.3%), F. verticillioides (16/17, 94.1%) and F. fujikuroi (19/25, 76.0%) produced both FB 1 and FB 2 . Notably, 16 of 19 fumonisin-producing F. fujikuroi produced >1000μg/g of fumonisins (FB 1 +FB 2 ) in rice medium, which is higher than that in previous reports. These results suggest that F. fujikuroi can produce

  9. Review of the Trifolium amabile Complex in Peru, with the Description of a New Species

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    Eduardo Antonio Molinari-Novoa

    2016-01-01

    Full Text Available Here, we describe Trifolium absconditum sp. nov., a new species of the T. amabile complex from South America. It differs from other Peruvian Trifolia of the complex by having smaller stipules, leaves, inflorescences, and floral pieces. A key for Peruvian species of the complex is presented, and typifications for them are made when necessary and material is available in Peruvian herbaria. Thus, the number of Peruvian species in the complex is elevated to three: T. amabile, T. absconditum, and a resurrected T. peruvianum. Finally, it is suggested that Chile must be excluded from the distribution of this complex.

  10. Comparative Genome Analysis of Lolium-Festuca Complex Species

    DEFF Research Database (Denmark)

    Czaban, Adrian; Byrne, Stephen; Sharma, Sapna

    2015-01-01

    , winter hardiness, drought tolerance and resistance to grazing. In this study we have sequenced and assembled the low copy fraction of the genomes of Lolium westerwoldicum, Lolium multiflorum, Festuca pratensis and Lolium temulentum. We have also generated de-novo transcriptome assemblies for each species......, and these have aided in the annotation of the genomic sequence. Using this data we were able to generate annotated assemblies of the gene rich regions of the four species to complement the already sequenced Lolium perenne genome. Using these gene models we have identified orthologous genes between the species...

  11. The Colletotrichum dracaenophilum, C. magnum and C. orchidearum species complexes

    NARCIS (Netherlands)

    Damm, U.; Sato, T.; Alizadeh, A.; Groenewald, J.Z.; Crous, P.W.

    2019-01-01

    Although Glomerella glycines, Colletotrichum magnum and C. orchidearum are known as causal agents of anthracnose of soybean, Cucurbitaceae and Orchidaceae, respectively, their taxonomy remains unresolved. In preliminary analyses based on ITS, strains of these species appear basal in

  12. Fungal endophytes isolated from Protium heptaphyllum and Trattinnickia rhoifolia as antagonists of Fusarium oxysporum.

    Science.gov (United States)

    Fierro-Cruz, Juan E; Jiménez, Pedro; Coy-Barrera, Ericsson

    Control of fungal pathogens is mainly addressed by the use of chemically synthesized fungicides which result in environmental pollution, developing resistance after prolonged use. In this context, endophytes have been recognized as potential biocontrollers, and also as a promising source of antifungal metabolites. Therefore, as part of our research on phytopathogen controllers, 355 fungal endophytes were isolated from Protium heptaphyllum and Trattinnickia rhoifolia (Burseraceae), both ethnobotanically important tree species that produce secondary metabolites of agronomic and industrial interest. Endophytes were tested by in vitro dual culture against Fusarium oxysporum, a phytopathogen of agronomic importance. Five endophytes exerted at least 40% inhibition on F. oxysporum growth. Ethyl acetate (EtOAc) extracts were obtained from the most active antagonistic fungi, after growing them in three different liquid media. The extracts were tested against a conidial suspension of F. oxysporum by direct bioautography. Two extracts derived from fungi identified as Chaetomium globosum, F211_UMNG and Meyerozima sp. F281_UMNG showed inhibition of pathogen growth. Isolate C. globosum, F211_UMNG was selected for a chemical analysis by RP-HPLC-DAD-ESI-MS and antifungal molecules such as cladosporin, chaetoatrosin A and chaetoviridin A were annotated and identified based on their MS data. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  13. Synthesis of CdSe Quantum Dots Using Fusarium oxysporum

    Directory of Open Access Journals (Sweden)

    Takaaki Yamaguchi

    2016-10-01

    Full Text Available CdSe quantum dots are often used in industry as fluorescent materials. In this study, CdSe quantum dots were synthesized using Fusarium oxysporum. The cadmium and selenium concentration, pH, and temperature for the culture of F. oxysporum (Fusarium oxysporum were optimized for the synthesis, and the CdSe quantum dots obtained from the mycelial cells of F. oxysporum were observed by transmission electron microscopy. Ultra-thin sections of F. oxysporum showed that the CdSe quantum dots were precipitated in the intracellular space, indicating that cadmium and selenium ions were incorporated into the cell and that the quantum dots were synthesized with intracellular metabolites. To reveal differences in F. oxysporum metabolism, cell extracts of F. oxysporum, before and after CdSe synthesis, were compared using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE. The results suggested that the amount of superoxide dismutase (SOD decreased after CdSe synthesis. Fluorescence microscopy revealed that cytoplasmic superoxide increased significantly after CdSe synthesis. The accumulation of superoxide may increase the expression of various metabolites that play a role in reducing Se4+ to Se2− and inhibit the aggregation of CdSe to make nanoparticles.

  14. Assessing species boundaries using multilocus species delimitation in a morphologically conserved group of neotropical freshwater fishes, the Poecilia sphenops species complex (Poeciliidae.

    Directory of Open Access Journals (Sweden)

    Justin C Bagley

    Full Text Available Accurately delimiting species is fundamentally important for understanding species diversity and distributions and devising effective strategies to conserve biodiversity. However, species delimitation is problematic in many taxa, including 'non-adaptive radiations' containing morphologically cryptic lineages. Fortunately, coalescent-based species delimitation methods hold promise for objectively estimating species limits in such radiations, using multilocus genetic data. Using coalescent-based approaches, we delimit species and infer evolutionary relationships in a morphologically conserved group of Central American freshwater fishes, the Poecilia sphenops species complex. Phylogenetic analyses of multiple genetic markers (sequences of two mitochondrial DNA genes and five nuclear loci from 10/15 species and genetic lineages recognized in the group support the P. sphenops species complex as monophyletic with respect to outgroups, with eight mitochondrial 'major-lineages' diverged by ≥2% pairwise genetic distances. From general mixed Yule-coalescent models, we discovered (conservatively 10 species within our concatenated mitochondrial DNA dataset, 9 of which were strongly supported by subsequent multilocus Bayesian species delimitation and species tree analyses. Results suggested species-level diversity is underestimated or overestimated by at least ~15% in different lineages in the complex. Nonparametric statistics and coalescent simulations indicate genealogical discordance among our gene tree results has mainly derived from interspecific hybridization in the nuclear genome. However, mitochondrial DNA show little evidence for introgression, and our species delimitation results appear robust to effects of this process. Overall, our findings support the utility of combining multiple lines of genetic evidence and broad phylogeographical sampling to discover and validate species using coalescent-based methods. Our study also highlights the

  15. Systematics of the Dendropsophus leucophyllatus species complex (Anura: Hylidae): Cryptic diversity and the description of two new species

    Science.gov (United States)

    Caminer, Marcel A.; Milá, Borja; Jansen, Martin; Fouquet, Antoine; Venegas, Pablo J.; Chávez, Germán; Lougheed, Stephen C.

    2017-01-01

    Genetic data in studies of systematics of Amazonian amphibians frequently reveal that purportedly widespread single species in reality comprise species complexes. This means that real species richness may be significantly higher than current estimates. Here we combine genetic, morphological, and bioacoustic data to assess the phylogenetic relationships and species boundaries of two Amazonian species of the Dendropsophus leucophyllatus species group: D. leucophyllatus and D. triangulum. Our results uncovered the existence of five confirmed and four unconfirmed candidate species. Among the confirmed candidate species, three have available names: Dendropsophus leucophyllatus, Dendropsophus triangulum, and Dendropsophus reticulatus, this last being removed from the synonymy of D. triangulum. A neotype of D. leucophyllatus is designated. We describe the remaining two confirmed candidate species, one from Bolivia and another from Peru. All confirmed candidate species are morphologically distinct and have much smaller geographic ranges than those previously reported for D. leucophyllatus and D. triangulum sensu lato. Dendropsophus leucophyllatus sensu stricto occurs in the Guianan region. Dendropsophus reticulatus comb. nov. corresponds to populations in the Amazon basin of Brazil, Ecuador, and Peru previously referred to as D. triangulum. Dendropsophus triangulum sensu stricto is the most widely distributed species; it occurs in Amazonian Ecuador, Peru and Brazil, reaching the state of Pará. We provide accounts for all described species including an assessment of their conservation status. PMID:28248998

  16. Comparative "Omics" of the Fusarium fujikuroi Species Complex Highlights Differences in Genetic Potential and Metabolite Synthesis

    NARCIS (Netherlands)

    Niehaus, E.-M.; Münsterkötter, M.; Proctor, R.H.; Brown, D.W.; Sharon, A.; Idan, Y.; Oren-Young, L.; Sieber, C.M.; Novák, O.; Pěnčík, A.; Tarkowská, D.; Hromadová, K.; Freeman, S.; Maymon, M.; Elazar, M.; Youssef, S.A.; El-Shabrawy, E.S.M.; Shalaby, A.B.A.; Houterman, P.; Brock, N.L.; Burkhardt, I.; Tsavkelova, E.A.; Dickschat, J.S.; Galuszka, P.; Güldener, U.; Tudzynski, B.

    2016-01-01

    Species of the Fusarium fujikuroi species complex (FFC) cause a wide spectrum of often devastating diseases on diverse agricultural crops, including coffee, fig, mango, maize, rice, and sugarcane. Although species within the FFC are difficult to distinguish by morphology, and their genes often share

  17. Comparison of Aspergillus species-complexes detected in different environmental settings

    OpenAIRE

    Sabino, Raquel; Viegas, Carla; Veríssimo, Carla; Clemons, K. V.; Stevens, D. A.

    2014-01-01

    Purpose: Samples from different environmental sources were screened for the presence of Aspergillus, and the distribution of the different species-complexes was determined in order to understand differences among that distribution in the several environmental sources and which of these species complexes are present in specific environmental settings. Methods: Four distinct environments (beaches, poultries, swineries and hospital) were studied and analyzed for which Aspergillus complexes were ...

  18. Urban habitat complexity affects species richness but not environmental filtering of morphologically-diverse ants

    Directory of Open Access Journals (Sweden)

    Alessandro Ossola

    2015-10-01

    Full Text Available Habitat complexity is a major determinant of structure and diversity of ant assemblages. Following the size-grain hypothesis, smaller ant species are likely to be advantaged in more complex habitats compared to larger species. Habitat complexity can act as an environmental filter based on species size and morphological traits, therefore affecting the overall structure and diversity of ant assemblages. In natural and semi-natural ecosystems, habitat complexity is principally regulated by ecological successions or disturbance such as fire and grazing. Urban ecosystems provide an opportunity to test relationships between habitat, ant assemblage structure and ant traits using novel combinations of habitat complexity generated and sustained by human management. We sampled ant assemblages in low-complexity and high-complexity parks, and high-complexity woodland remnants, hypothesizing that (i ant abundance and species richness would be higher in high-complexity urban habitats, (ii ant assemblages would differ between low- and high-complexity habitats and (iii ants living in high-complexity habitats would be smaller than those living in low-complexity habitats. Contrary to our hypothesis, ant species richness was higher in low-complexity habitats compared to high-complexity habitats. Overall, ant assemblages were significantly different among the habitat complexity types investigated, although ant size and morphology remained the same. Habitat complexity appears to affect the structure of ant assemblages in urban ecosystems as previously observed in natural and semi-natural ecosystems. However, the habitat complexity filter does not seem to be linked to ant morphological traits related to body size.

  19. Urban habitat complexity affects species richness but not environmental filtering of morphologically-diverse ants

    Science.gov (United States)

    Nash, Michael A.; Christie, Fiona J.; Hahs, Amy K.; Livesley, Stephen J.

    2015-01-01

    Habitat complexity is a major determinant of structure and diversity of ant assemblages. Following the size-grain hypothesis, smaller ant species are likely to be advantaged in more complex habitats compared to larger species. Habitat complexity can act as an environmental filter based on species size and morphological traits, therefore affecting the overall structure and diversity of ant assemblages. In natural and semi-natural ecosystems, habitat complexity is principally regulated by ecological successions or disturbance such as fire and grazing. Urban ecosystems provide an opportunity to test relationships between habitat, ant assemblage structure and ant traits using novel combinations of habitat complexity generated and sustained by human management. We sampled ant assemblages in low-complexity and high-complexity parks, and high-complexity woodland remnants, hypothesizing that (i) ant abundance and species richness would be higher in high-complexity urban habitats, (ii) ant assemblages would differ between low- and high-complexity habitats and (iii) ants living in high-complexity habitats would be smaller than those living in low-complexity habitats. Contrary to our hypothesis, ant species richness was higher in low-complexity habitats compared to high-complexity habitats. Overall, ant assemblages were significantly different among the habitat complexity types investigated, although ant size and morphology remained the same. Habitat complexity appears to affect the structure of ant assemblages in urban ecosystems as previously observed in natural and semi-natural ecosystems. However, the habitat complexity filter does not seem to be linked to ant morphological traits related to body size. PMID:26528416

  20. Environmental Screening for the Scedosporium apiospermum Species Complex in Public Parks in Bangkok, Thailand.

    Directory of Open Access Journals (Sweden)

    Natthanej Luplertlop

    Full Text Available The Scedosporium apiospermum species complex, comprising filamentous fungal species S. apiospermum sensu stricto, S. boydii, S. aurantiacum, S. dehoogii and S. minutispora, are important pathogens that cause a wide variety of infections. Although some species (S. boydii and S. apiospermum have been isolated from patients in Thailand, no environmental surveys of these fungi have been performed in Thailand or surrounding countries. In this study, we isolated and identified species of these fungi from 68 soil and 16 water samples randomly collected from 10 parks in Bangkok. After filtration and subsequent inoculation of samples on Scedo-Select III medium, colony morphological examinations and microscopic observations were performed. Scedosporium species were isolated from soil in 8 of the 10 parks, but were only detected in one water sample. Colony morphologies of isolates from 41 of 68 soil samples (60.29% and 1 of 15 water samples (6.67% were consistent with that of the S. apiospermum species complex. Each morphological type was selected for species identification based on DNA sequencing and phylogenetic analysis of the β-tubulin gene. Three species of the S. apiospermum species complex were identified: S. apiospermum (71 isolates, S. aurantiacum (6 isolates and S. dehoogii (5 isolates. In addition, 16 sequences could not be assigned to an exact Scedosporium species. According to our environmental survey, the S. apiospermum species complex is widespread in soil in Bangkok, Thailand.

  1. Assessment of compost for suppression of Fusarium oxysporum and ...

    African Journals Online (AJOL)

    user

    2012-08-28

    Aug 28, 2012 ... Biological characteristics including compost inhabiting microbial ... A solid-liquid extraction was carried out then; pH was determined by using AS-501 pH ...... oxysporum in sweet basil. Crop Prot. ... Pesticide Biochem. Physiol.

  2. Evidence for horizontal gene transfer and separation of effector recognition from effector function revealed by analysis of effector genes shared between cape-gooseberry- and tomato-infecting formae speciales of Fusarium oxysporum.

    Science.gov (United States)

    Simbaqueba, Jaime; Catanzariti, Ann-Maree; González, Carolina; Jones, David A

    2018-05-22

    RNAseq reads from cape-gooseberry plants (Physalis peruviana) infected with Fusarium oxysporum f. sp. physali (Foph) were mapped against the lineage-specific transcriptome of Fusarium oxysporum f. sp. lycopersici (Fol) to look for putative effector genes. Homologues of Fol SIX1 (designated SIX1a and SIX1b), SIX7, SIX10, SIX12, SIX15 and Ave1 were identified. The near identity of the Foph and Fol SIX7, SIX10 and SIX12 genes and their intergenic regions suggest that this gene cluster may have undergone recent lateral transfer. Foph SIX1a and SIX1b were tested for their ability to complement a SIX1 knockout mutant of Fol. This mutant has reduced pathogenicity on susceptible tomato plants, but is able to infect otherwise resistant tomato plants carrying the I-3 gene for Fusarium wilt resistance (SIX1 corresponds to Avr3). Neither, SIX1a nor SIX1b could restore full pathogenicity on susceptible tomato plants, suggesting that any role they may play in pathogenicity is likely to be specific to cape gooseberry. SIX1b, but not SIX1a, was able to restore avirulence on tomato plants carrying I-3. These findings separate the recognition of SIX1 from its role as an effector and suggest direct recognition by I-3. A hypervariable region of SIX1 undergoing diversifying selection within the F. oxysporum species complex is likely to play an important role in SIX1 recognition. These findings also indicate that I-3 could potentially be deployed as a transgene in cape gooseberry to protect this emerging crop from Foph. Alternatively, cape gooseberry germplasm could be explored for I-3 homologues capable of providing resistance to Foph. This article is protected by copyright. All rights reserved. © 2018 BSPP and John Wiley & Sons Ltd.

  3. Genome-wide analyses of the Bemisia tabaci species complex reveal contrasting patterns of admixture and complex demographic histories.

    Directory of Open Access Journals (Sweden)

    S Elfekih

    Full Text Available Once considered a single species, the whitefly, Bemisia tabaci, is a complex of numerous morphologically indistinguishable species. Within the last three decades, two of its members (MED and MEAM1 have become some of the world's most damaging agricultural pests invading countries across Europe, Africa, Asia and the Americas and affecting a vast range of agriculturally important food and fiber crops through both feeding-related damage and the transmission of numerous plant viruses. For some time now, researchers have relied on a single mitochondrial gene and/or a handful of nuclear markers to study this species complex. Here, we move beyond this by using 38,041 genome-wide Single Nucleotide Polymorphisms, and show that the two invasive members of the complex are closely related species with signatures of introgression with a third species (IO. Gene flow patterns were traced between contemporary invasive populations within MED and MEAM1 species and these were best explained by recent international trade. These findings have profound implications for delineating the B. tabaci species status and will impact quarantine measures and future management strategies of this global pest.

  4. Onychomycosis by Fusarium oxysporum probably acquired in utero

    Directory of Open Access Journals (Sweden)

    Vania O. Carvalho

    2014-10-01

    Full Text Available Fusarium oxysporum has been described as a pathogen causing onychomycosis, its incidence has been increasing in immunocompetent and disseminated infection can occur in immunosuppressed individuals. We describe the first case of congenital onychomycosis in a child caused by Fusarium oxysporum. The infection being acquired in utero was proven by molecular methods with the identification of the fungus both in the nail and placenta, most probably as an ascending contamination/infection in a HIV-positive, immunosuppressed mother.

  5. Systematics of the Trichoderma harzianum species complex and the re-identification of commercial biocontrol strains

    Science.gov (United States)

    Jaklitsch, Walter; Gazis, Romina; Degenkolb, Thomas; Samuels, Gary J.

    2016-01-01

    Trichoderma harzianum is known as a cosmopolitan, ubiquitous species associated with a wide variety of substrates. It is possibly the most commonly used name in agricultural applications involving Trichoderma, including biological control of plant diseases. While various studies have suggested that T. harzianum is a species complex, only a few cryptic species are named. In the present study the taxonomy of the T. harzianum species complex is revised to include at least 14 species. Previously named species included in the complex are T. guizhouense, T. harzianum, and T. inhamatum. Two new combinations are proposed, T. lentiforme and T. lixii. Nine species are described as new, T. afarasin, T. afroharzianum, T. atrobrunneum, T. camerunense, T. endophyticum, T. neotropicale, T. pyramidale, T. rifaii and T. simmonsii. We isolated Trichoderma cultures from four commercial biocontrol products reported to contain T. harzianum. None of the biocontrol strains were identified as T. harzianum s. str. In addition, the widely applied culture ‘T. harzianum T22’ was determined to be T. afroharzianum. Some species in the T. harzianum complex appear to be exclusively endophytic, while others were only isolated from soil. Sexual states are rare. Descriptions and illustrations are provided. A secondary barcode, nuc translation elongation factor 1-α (TEF1) is needed to identify species in this complex. PMID:25661720

  6. Systematics of the Trichoderma harzianum species complex and the re-identification of commercial biocontrol strains.

    Science.gov (United States)

    Chaverri, Priscila; Branco-Rocha, Fabiano; Jaklitsch, Walter; Gazis, Romina; Degenkolb, Thomas; Samuels, Gary J

    2015-01-01

    Trichoderma harzianum is known as a cosmopolitan, ubiquitous species associated with a wide variety of substrates. It is possibly the most commonly used name in agricultural applications involving Trichoderma, including biological control of plant diseases. While various studies have suggested that T. harzianum is a species complex, only a few cryptic species are named. In the present study the taxonomy of the T. harzianum species complex is revised to include at least 14 species. Previously named species included in the complex are T. guizhouense, T. harzianum, and T. inhamatum. Two new combinations are proposed, T. lentiforme and T. lixii. Nine species are described as new, T. afarasin, T. afroharzianum, T. atrobrunneum, T. camerunense, T. endophyticum, T. neotropicale, T. pyramidale, T. rifaii and T. simmonsii. We isolated Trichoderma cultures from four commercial biocontrol products reported to contain T. harzianum. None of the biocontrol strains were identified as T. harzianum s. str. In addition, the widely applied culture 'T. harzianum T22' was determined to be T. afroharzianum. Some species in the T. harzianum complex appear to be exclusively endophytic, while others were only isolated from soil. Sexual states are rare. Descriptions and illustrations are provided. A secondary barcode, nuc translation elongation factor 1-α (TEF1) is needed to identify species in this complex. © 2015 by The Mycological Society of America.

  7. Trichoderma harzianum containing 1-aminocyclopropane-1-carboxylate deaminase and chitinase improved growth and diminished adverse effect caused by Fusarium oxysporum in soybean.

    Science.gov (United States)

    Zhang, Fuli; Chen, Can; Zhang, Fan; Gao, Lidong; Liu, Jidong; Chen, Long; Fan, Xiaoning; Liu, Chang; Zhang, Ke; He, Yuting; Chen, Chen; Ji, Xiue

    2017-03-01

    An isolate, named Trichoderma harzianum T-soybean, showed growth-promoting for soybean seedlings and induced resistance to Fusarium oxysporum under greenhouse. Compared to control soybean seedlings, fresh weight, dry weight, lateral root number, chlorophyll content, root activity and soluble protein of plants pretreated with T-soybean increased, but initial pod height reduced. Furthermore, we found that T-soybean inhibited the growth of F. oxysporum by parasitic function. In addition, plate test results showed that culture filtrates of T-soybean also inhibited significantly F. oxysporum growth. Meanwhile, T-soybean treatment obviously reduced disease severity and induced quickly the H 2 O 2 and O 2 - burst as well as pathogenesis related protein gene (PR3) expression after F. oxysporum inoculation, and subsequently diminished the cell damage in soybean caused by the pathogen challenge. Reactive oxygen species (ROS) scavenging enzymes activity analysis showed that the activities of peroxidase (POD), polyphenol oxidase (PPO) and superoxide dismutase (SOD) increased significantly in T-soybean pretreated plants. These results suggested that T-soybean treatment induced resistance in soybean seedlings to F. oxysporum by companying the production of ROS and the increasing of ROS scavenging enzymes activity as well as PR3 expression. Copyright © 2016 Elsevier GmbH. All rights reserved.

  8. A proteomics approach to study synergistic and antagonistic interactions of the fungal-bacterial consortium Fusarium oxysporum wild-type MSA 35.

    Science.gov (United States)

    Moretti, Marino; Grunau, Alexander; Minerdi, Daniela; Gehrig, Peter; Roschitzki, Bernd; Eberl, Leo; Garibaldi, Angelo; Gullino, Maria Lodovica; Riedel, Kathrin

    2010-09-01

    Fusarium oxysporum is an important plant pathogen that causes severe damage of many economically important crop species. Various microorganisms have been shown to inhibit this soil-borne plant pathogen, including non-pathogenic F. oxysporum strains. In this study, F. oxysporum wild-type (WT) MSA 35, a biocontrol multispecies consortium that consists of a fungus and numerous rhizobacteria mainly belonging to gamma-proteobacteria, was analyzed by two complementary metaproteomic approaches (2-DE combined with MALDI-Tof/Tof MS and 1-D PAGE combined with LC-ESI-MS/MS) to identify fungal or bacterial factors potentially involved in antagonistic or synergistic interactions between the consortium members. Moreover, the proteome profiles of F. oxysporum WT MSA 35 and its cured counter-part CU MSA 35 (WT treated with antibiotics) were compared with unravel the bacterial impact on consortium functioning. Our study presents the first proteome mapping of an antagonistic F. oxysporum strain and proposes candidate proteins that might play an important role for the biocontrol activity and the close interrelationship between the fungus and its bacterial partners.

  9. Delimitating cryptic species in the Gracilaria domingensis complex (Gracilariaceae, Rhodophyta) using molecular and morphological data.

    Science.gov (United States)

    Lyra, Goia de M; Gurgel, C Frederico D; Costa, Emmanuelle da S; de Jesus, Priscila B; Oliveira, Mariana C; Oliveira, Eurico C; Davis, Charles C; Nunes, José Marcos de Castro

    2016-12-01

    Species in the genus Gracilaria that display conspicuously flattened vegetative morphologies are a taxonomically challenging group of marine benthic red algae. This is a result of their species richness, morphological similarity, and broad phenotypic plasticity. Within this group, the Gracilaria domingensis complex is one of the most common, conspicuous, and morphologically variable species along the tropical western Atlantic Ocean. Previous research has identified that members of this complex belong to two distantly related clades. However, despite this increased phylogentic resolution, species delimitations within each of these clades remain unclear. Our study assessed the species diversity within this difficult complex using morphological and molecular data from three genetic markers (cox1, UPA, and rbcL). We additionally applied six single-marker species delimitation methods (SDM: ABGD, GMYCs, GMYCm, SPN, bPTP, and PTP) to rbcL, which were largely in agreement regarding species delimitation. These results, combined with our analysis of morphology, indicate that the G. domingensis complex includes seven distinct species, each of which are not all most closely related: G. cervicornis; a ressurected G. ferox; G. apiculata subsp. apiculata; a new species, Gracilaria baiana sp. nov.; G. intermedia subsp. intermedia; G. venezuelensis; and G. domingensis sensu stricto, which includes the later heterotypic synonym, G. yoneshigueana. Our study demonstrates the value of multipronged strategies, including the use of both molecular and morphological approaches, to decipher cryptic species of red algae. © 2016 Phycological Society of America.

  10. Systematics of the Platyrrhinus helleri species complex (Chiroptera: Phyllostomidae), with descriptions of two new species

    Science.gov (United States)

    Velazco, Paúl M.; Gardner, Alfred L.; Patterson, Bruce D.

    2010-01-01

    Platyrrhinus is a diverse genus of small to large phyllostomid bats characterized by a comparatively narrow uropatagium thickly fringed with hair, a white dorsal stripe, comparatively large inner upper incisors that are convergent at the tips, and three upper and three lower molars. Eighteen species are currently recognized, the majority occurring in the Andes. Molecular, morphological, and morphometric analyses of specimens formerly identified as Platyrrhinus helleri support recognition of Platyrrhinus incarum as a separate species and reveal the presence of two species from western and northern South America that we describe herein as new (Platyrrhinus angustirostris sp. nov. from eastern Colombia and Ecuador, north-eastern Peru, and Venezuela and Platyrrhinus fusciventris sp. nov. from Guyana, Suriname, French Guiana, Trinidad and Tobago, northern Brazil, eastern Ecuador, and southern Venezuela). These two new species are sister taxa and, in turn, sister to Platyrrhinus incarum.

  11. Adaptation of Fusarium oxysporum and Fusarium dimerum to the specific aquatic environment provided by the water systems of hospitals.

    Science.gov (United States)

    Steinberg, Christian; Laurent, Julie; Edel-Hermann, Véronique; Barbezant, Marie; Sixt, Nathalie; Dalle, Frédéric; Aho, Serge; Bonnin, Alain; Hartemann, Philippe; Sautour, Marc

    2015-06-01

    Members of the Fusarium group were recently detected in water distribution systems of several hospitals in the world. An epidemiological investigation was conducted over 2 years in hospital buildings in Dijon and Nancy (France) and in non-hospital buildings in Dijon. The fungi were detected only within the water distribution systems of the hospital buildings and also, but at very low concentrations, in the urban water network of Nancy. All fungi were identified as Fusarium oxysporum species complex (FOSC) and Fusarium dimerum species complex (FDSC) by sequencing part of the translation elongation factor 1-alpha (TEF-1α) gene. Very low diversity was found in each complex, suggesting the existence of a clonal population for each. Density and heterogeneous distributions according to buildings and variability over time were explained by episodic detachments of parts of the colony from biofilms in the pipes. Isolates of these waterborne populations as well as soilborne isolates were tested for their ability to grow in liquid medium in the presence of increasing concentrations of sodium hypochlorite, copper sulfate, anti-corrosion pipe coating, at various temperatures (4°-42 °C) and on agar medium with amphotericin B and voriconazole. The waterborne isolates tolerated higher sodium hypochlorite and copper sulfate concentrations and temperatures than did soilborne isolates but did not show any specific resistance to fungicides. In addition, unlike waterborne isolates, soilborne isolates did not survive in water even supplemented with glucose, while the former developed in the soil as well as soilborne isolates. We concluded the existence of homogeneous populations of FOSC and FDSC common to all contaminated hospital sites. These populations are present at very low densities in natural waters, making them difficult to detect, but they are adapted to the specific conditions offered by the complex water systems of public hospitals in Dijon and Nancy and probably other

  12. Defining species boundaries in the Merodon avidus complex (Diptera, Syrphidae using integrative taxonomy, with the description of a new species

    Directory of Open Access Journals (Sweden)

    Jelena Ačanski

    2016-10-01

    Full Text Available Several recent studies have detected and described complexes of cryptic and sibling species in the genus Merodon (Diptera, Syrphidae. One representative of these complexes is the Merodon avidus complex that contains four sibling species, which have proven difficult to distinguish using traditional morphological characters. In the present study, we use two geometric morphometric approaches, as well as molecular characters of the 5’-end of the mtDNA COI gene, to delimit sibling taxa. Analyses based on these data were used to strengthen species boundaries within the complex, and to validate the status of a previously-recognized cryptic taxon from Lesvos Island (Greece, here described as Merodon megavidus Vujić & Radenković sp. nov. Geometric morphometric results of both wing and surstylus shape confirm the present classification for three sibling species-M. avidus (Rossi, 1790, M. moenium Wiedemann in Meigen, 1822 and M. ibericus Vujić, 2015-and, importantly, clearly discriminate the newly-described taxon Merodon megavidus sp. nov. In addition to our geometric morphometric results, supporting characters were obtained from molecular analyses of mtDNA COI sequences, which clearly differentiated M. megavidus sp. nov. from the other members of the M. avidus complex. Molecular analyses revealed that the earliest divergence of M. ibericus occurred around 800 ky BP, while the most recent separation happened between M. avidus and M. moenium around 87 ky BP.

  13. The effects of model and data complexity on predictions from species distributions models

    DEFF Research Database (Denmark)

    García-Callejas, David; Bastos, Miguel

    2016-01-01

    How complex does a model need to be to provide useful predictions is a matter of continuous debate across environmental sciences. In the species distributions modelling literature, studies have demonstrated that more complex models tend to provide better fits. However, studies have also shown...... that predictive performance does not always increase with complexity. Testing of species distributions models is challenging because independent data for testing are often lacking, but a more general problem is that model complexity has never been formally described in such studies. Here, we systematically...

  14. Volatile compounds in cryptic species of the Aneura pinguis complex and Aneura maxima (Marchantiophyta, Metzgeriidae).

    Science.gov (United States)

    Wawrzyniak, Rafał; Wasiak, Wiesław; Bączkiewicz, Alina; Buczkowska, Katarzyna

    2014-09-01

    Aneura pinguis is one of the liverwort species complexes that consist of several cryptic species. Ten samples collected from different regions in Poland are in the focus of our research. Eight of the A. pinguis complex belonging to four cryptic species (A, B, C, E) and two samples of closely related species Aneura maxima were tested for the composition of volatile compounds. The HS-SPME technique coupled to GC/FID and GC/MS analysis has been applied. The fiber coated with DVB/CAR/PDMS has been used. The results of the present study, revealed the qualitative and quantitative differences in the composition of the volatile compounds between the studied species. Mainly they are from the group of sesquiterpenoids, oxygenated sesquiterpenoids and aliphatic hydrocarbons. The statistical methods (CA and PCA) showed that detected volatile compounds allow to distinguish cryptic species of A. pinguis. All examined cryptic species of the A. pinguis complex differ from A. maxima. Species A and E of A. pinguis, in CA and PCA, form separate clusters remote from two remaining cryptic species of A. pinguis (B and C) and A. maxima. Relationship between the cryptic species appeared from the chemical studies are in accordance with that revealed on the basis of DNA sequences. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Evidence for the robustness of protein complexes to inter-species hybridization.

    Directory of Open Access Journals (Sweden)

    Jean-Baptiste Leducq

    Full Text Available Despite the tremendous efforts devoted to the identification of genetic incompatibilities underlying hybrid sterility and inviability, little is known about the effect of inter-species hybridization at the protein interactome level. Here, we develop a screening platform for the comparison of protein-protein interactions (PPIs among closely related species and their hybrids. We examine in vivo the architecture of protein complexes in two yeast species (Saccharomyces cerevisiae and Saccharomyces kudriavzevii that diverged 5-20 million years ago and in their F1 hybrids. We focus on 24 proteins of two large complexes: the RNA polymerase II and the nuclear pore complex (NPC, which show contrasting patterns of molecular evolution. We found that, with the exception of one PPI in the NPC sub-complex, PPIs were highly conserved between species, regardless of protein divergence. Unexpectedly, we found that the architecture of the complexes in F1 hybrids could not be distinguished from that of the parental species. Our results suggest that the conservation of PPIs in hybrids likely results from the slow evolution taking place on the very few protein residues involved in the interaction or that protein complexes are inherently robust and may accommodate protein divergence up to the level that is observed among closely related species.

  16. Species of the Colletotrichum acutatum complex associated with anthracnose diseases of fruit in Brazil

    NARCIS (Netherlands)

    Bragança, Carlos A.D.; Damm, Ulrike; Baroncelli, Riccardo; Massola Júnior, Nelson S.; Crous, Pedro W.

    Abstract Although Colletotrichum acutatum was recently investigated and shown to be a species complex comprising about 30 species, the name is still used in its broad sense for anthracnose pathogens of fruits in Brazil. In this study, a multilocus molecular analysis was carried out based on a

  17. Taxonomy and phylogeny of Pluteus glaucotinctus sensu lato (Agaricales, Basidiomycota), a multicontinental species complex

    Science.gov (United States)

    Nelson Menolli; Alfredo Justo; Pedro Arrillaga; C.K. Pradeep; Andrew M. Minnis; Marina. Capelari

    2014-01-01

    In order to better understand species delimitation in the Pluteus glaucotinctus species complex, we present a detailed study based on morphological and DNA sequence (nrITS + tef1) data. Pluteus glaucotinctus sensu stricto is known only from the type collection (Democratic Republic of the Congo), which is re-...

  18. Differential response of banana cultivars to F. oxysporum f. sp. cubense infection for Chitinase activity

    International Nuclear Information System (INIS)

    Morpurgo, R.; Duren, M. Van; Grasso, G.; Afza, R.

    1997-01-01

    Six banana clones with varying levels of resistance were inoculated with conidial suspension of races 1 and 4 of Fusarium oxysporum f. sp. cubense. Chitanase activity in the corm and root tissues was monitored before and after infection to relate with the field resistance or susceptibility of banana cultivars. Resistant clones showed high constitutive chitinase activity in roots and a rapid response to infection. The results suggest that chitinase could be considered as part of a complex mechanism leading to disease resistance. (author). 5 refs, 8 figs

  19. Differential response of banana cultivars to F. oxysporum f. sp. cubense infection for Chitinase activity

    Energy Technology Data Exchange (ETDEWEB)

    Morpurgo, R; Duren, M Van; Grasso, G; Afza, R [Agriculture and Biotechnology Laboratory, International Atomic Energy Agency, Seibersdorf (Austria)

    1997-07-01

    Six banana clones with varying levels of resistance were inoculated with conidial suspension of races 1 and 4 of Fusarium oxysporum f. sp. cubense. Chitanase activity in the corm and root tissues was monitored before and after infection to relate with the field resistance or susceptibility of banana cultivars. Resistant clones showed high constitutive chitinase activity in roots and a rapid response to infection. The results suggest that chitinase could be considered as part of a complex mechanism leading to disease resistance. (author). 5 refs, 8 figs.

  20. Fusarium oxysporum induces the production of proteins and volatile organic compounds by Trichoderma harzianum T-E5.

    Science.gov (United States)

    Zhang, Fengge; Yang, Xingming; Ran, Wei; Shen, Qirong

    2014-10-01

    Trichoderma species have been used widely as biocontrol agents for the suppression of soil-borne pathogens. However, some antagonistic mechanisms of Trichoderma are not well characterized. In this study, a series of laboratory experiments were designed to characterize the importance of mycoparasitism, exoenzymes, and volatile organic compounds (VOCs) by Trichoderma harzianum T-E5 for the control of Fusarium oxysporum f. sp. cucumerinum (FOC). We further tested whether these mechanisms were inducible and upregulated in presence of FOC. The results were as follows: T-E5 heavily parasitized FOC by coiling and twisting the entire mycelium of the pathogen in dual cultures. T-E5 growing medium conditioned with deactivated FOC (T2) showed more proteins and higher cell wall-degrading enzyme activities than T1, suggesting that FOC could induce the upregulation of exoenzymes. The presence of deactivated FOC (T2') also resulted in the upregulation of VOCs that five and eight different types T-E5-derived VOCs were identified from T1' and T2', respectively. Further, the excreted VOCs in T2' showed significantly higher antifungal activities against FOC than T1'. In conclusion, mycoparasitism of T-E5 against FOC involved mycelium contact and the production of complex extracellular substances. Together, these data provide clues to help further clarify the interactions between these fungi. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  1. Outbreak of Fusarium oxysporum infections in children with cancer: an experience with 7 episodes of catheter-related fungemia.

    Science.gov (United States)

    Carlesse, Fabianne; Amaral, Anna-Paula C; Gonçalves, Sarah S; Xafranski, Hemilio; Lee, Maria-Lucia M; Zecchin, Victor; Petrilli, Antonio S; Al-Hatmi, Abdullah M; Hagen, Ferry; Meis, Jacques F; Colombo, Arnaldo L

    2017-01-01

    Fusarium species are widely spread in nature as plant pathogens but are also able to cause opportunistic fungal infections in humans. We report a cluster of Fusarium oxysporum bloodstream infections in a single pediatric cancer center. All clinical and epidemiological data related to an outbreak involving seven cases of fungemia by Fusarium oxysporum during October 2013 and February 2014 were analysed. All cultured isolates ( n  = 14) were identified to species level by sequencing of the TEF1 and RPB2 genes. Genotyping of the outbreak isolates was performed by amplified fragment length polymorphism fingerprinting. In a 5-month period 7 febrile pediatric cancer patients were diagnosed with catheter-related Fusarium oxysporum bloodstream infections. In a time span of 11 years, only 6 other infections due to Fusarium were documented and all were caused by a different species, Fusarium solani . None of the pediatric cancer patients had neutropenia at the time of diagnosis and all became febrile within two days after catheter manipulation in a specially designed room. Extensive environmental sampling in this room and the hospital did not gave a clue to the source. The outbreak was terminated after implementation of a multidisciplinary central line insertion care bundle. All Fusarium strains from blood and catheter tips were genetically related by amplified fragment length polymorphism fingerprinting. All patients survived the infection after prompt catheter removal and antifungal therapy. A cluster with, genotypical identical, Fusarium oxysporum strains infecting 7 children with cancer, was most probably catheter-related. The environmental source was not discovered but strict infection control measures and catheter care terminated the outbreak.

  2. Outbreak of Fusarium oxysporum infections in children with cancer: an experience with 7 episodes of catheter-related fungemia

    Directory of Open Access Journals (Sweden)

    Fabianne Carlesse

    2017-09-01

    Full Text Available Abstract Background Fusarium species are widely spread in nature as plant pathogens but are also able to cause opportunistic fungal infections in humans. We report a cluster of Fusarium oxysporum bloodstream infections in a single pediatric cancer center. Methods All clinical and epidemiological data related to an outbreak involving seven cases of fungemia by Fusarium oxysporum during October 2013 and February 2014 were analysed. All cultured isolates (n = 14 were identified to species level by sequencing of the TEF1 and RPB2 genes. Genotyping of the outbreak isolates was performed by amplified fragment length polymorphism fingerprinting. Results In a 5-month period 7 febrile pediatric cancer patients were diagnosed with catheter-related Fusarium oxysporum bloodstream infections. In a time span of 11 years, only 6 other infections due to Fusarium were documented and all were caused by a different species, Fusarium solani. None of the pediatric cancer patients had neutropenia at the time of diagnosis and all became febrile within two days after catheter manipulation in a specially designed room. Extensive environmental sampling in this room and the hospital did not gave a clue to the source. The outbreak was terminated after implementation of a multidisciplinary central line insertion care bundle. All Fusarium strains from blood and catheter tips were genetically related by amplified fragment length polymorphism fingerprinting. All patients survived the infection after prompt catheter removal and antifungal therapy. Conclusion A cluster with, genotypical identical, Fusarium oxysporum strains infecting 7 children with cancer, was most probably catheter-related. The environmental source was not discovered but strict infection control measures and catheter care terminated the outbreak.

  3. 76 FR 80385 - Draft Environmental Impact Statement and Proposed Maricopa Sun Solar Complex Multi-Species...

    Science.gov (United States)

    2011-12-23

    .... Operation related activities could include solar panel maintenance, on-site parking, operation of solar...-FXES11120800000F2-123] Draft Environmental Impact Statement and Proposed Maricopa Sun Solar Complex Multi-Species... National Environmental Policy Act for the proposed Maricopa Sun Solar Complex Habitat Conservation Plan...

  4. Continental Drift and Speciation of the Cryptococcus neoformans and Cryptococcus gattii Species Complexes

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    Arturo Casadevall

    2017-04-01

    Full Text Available Genomic analysis has placed the origins of two human-pathogenic fungi, the Cryptococcus gattii species complex and the Cryptococcus neoformans species complex, in South America and Africa, respectively. Molecular clock calculations suggest that the two species separated ~80 to 100 million years ago. This time closely approximates the breakup of the supercontinent Pangea, which gave rise to South America and Africa. On the basis of the geographic distribution of these two species complexes and the coincidence of the evolutionary divergence and Pangea breakup times, we propose that a spatial separation caused by continental drift resulted in the emergence of the C. gattii and C. neoformans species complexes from a Pangean ancestor. We note that, despite the spatial and temporal separation that occurred approximately 100 million years ago, these two species complexes are morphologically similar, share virulence factors, and cause very similar diseases. Continuation of these phenotypic characteristics despite ancient separation suggests the maintenance of similar selection pressures throughout geologic ages.

  5. Cryptic Species Identification and Composition of Bemisia tabaci (Hemiptera: Aleyrodidae) Complex in Henan Province, China

    Science.gov (United States)

    Hu, Jian; Wang, Lun-Ji; Dong, Jun-Feng; Song, Yue-Qin; Sun, Hui-Zhong

    2017-01-01

    Abstract Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a cryptic species complex, causing significant crop losses in China during the last decade. Although knowledge of cryptic species composition and dynamics within B. tabaci complex is critical for developing sustainable pest management strategies, limited information is available on this pest in the Henan province of China. A systematic survey of the cryptic species composition and distribution of B. tabaci complex in different locations of Henan province was conducted in 2012. The results of RAPD-PCR and the gene for the mitochondrial cytochrome oxidase subunit-1 (mtCOI) based phylogenetic relationships established using Bayesian method indicated there were four known cryptic species MEAM1, MED, Asia II 3, Asia II 9 and a new cryptic species named China 6 in Henan province. In the survey, the invasive cryptic species MED and MEAM1 were found to be predominant with wide spread distribution across the surveyed regions. On the contrary, the indigenous B. tabaci cryptic species including Asia II 3, Asia II 9 and China 6 remained with low prevalence in some surveyed regions. Cryptic species MEAM1 and MED have not completely displaced the native B. tabaci in Henan province. This current study for the first time unifies our knowledge of the diversity and distribution of B. tabaci across Henan province of China. PMID:28973577

  6. Cryptic Species Identification and Composition of Bemisia tabaci (Hemiptera: Aleyrodidae) Complex in Henan Province, China.

    Science.gov (United States)

    Jiu, Min; Hu, Jian; Wang, Lun-Ji; Dong, Jun-Feng; Song, Yue-Qin; Sun, Hui-Zhong

    2017-05-01

    Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a cryptic species complex, causing significant crop losses in China during the last decade. Although knowledge of cryptic species composition and dynamics within B. tabaci complex is critical for developing sustainable pest management strategies, limited information is available on this pest in the Henan province of China. A systematic survey of the cryptic species composition and distribution of B. tabaci complex in different locations of Henan province was conducted in 2012. The results of RAPD-PCR and the gene for the mitochondrial cytochrome oxidase subunit-1 (mtCOI) based phylogenetic relationships established using Bayesian method indicated there were four known cryptic species MEAM1, MED, Asia II 3, Asia II 9 and a new cryptic species named China 6 in Henan province. In the survey, the invasive cryptic species MED and MEAM1 were found to be predominant with wide spread distribution across the surveyed regions. On the contrary, the indigenous B. tabaci cryptic species including Asia II 3, Asia II 9 and China 6 remained with low prevalence in some surveyed regions. Cryptic species MEAM1 and MED have not completely displaced the native B. tabaci in Henan province. This current study for the first time unifies our knowledge of the diversity and distribution of B. tabaci across Henan province of China. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  7. Genome size evolution at the speciation level: the cryptic species complex Brachionus plicatilis (Rotifera).

    Science.gov (United States)

    Stelzer, Claus-Peter; Riss, Simone; Stadler, Peter

    2011-04-07

    Studies on genome size variation in animals are rarely done at lower taxonomic levels, e.g., slightly above/below the species level. Yet, such variation might provide important clues on the tempo and mode of genome size evolution. In this study we used the flow-cytometry method to study the evolution of genome size in the rotifer Brachionus plicatilis, a cryptic species complex consisting of at least 14 closely related species. We found an unexpectedly high variation in this species complex, with genome sizes ranging approximately seven-fold (haploid '1C' genome sizes: 0.056-0.416 pg). Most of this variation (67%) could be ascribed to the major clades of the species complex, i.e. clades that are well separated according to most species definitions. However, we also found substantial variation (32%) at lower taxonomic levels--within and among genealogical species--and, interestingly, among species pairs that are not completely reproductively isolated. In one genealogical species, called B. 'Austria', we found greatly enlarged genome sizes that could roughly be approximated as multiples of the genomes of its closest relatives, which suggests that whole-genome duplications have occurred early during separation of this lineage. Overall, genome size was significantly correlated to egg size and body size, even though the latter became non-significant after controlling for phylogenetic non-independence. Our study suggests that substantial genome size variation can build up early during speciation, potentially even among isolated populations. An alternative, but not mutually exclusive interpretation might be that reproductive isolation tends to build up unusually slow in this species complex.

  8. Genome size evolution at the speciation level: The cryptic species complex Brachionus plicatilis (Rotifera

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    Riss Simone

    2011-04-01

    Full Text Available Abstract Background Studies on genome size variation in animals are rarely done at lower taxonomic levels, e.g., slightly above/below the species level. Yet, such variation might provide important clues on the tempo and mode of genome size evolution. In this study we used the flow-cytometry method to study the evolution of genome size in the rotifer Brachionus plicatilis, a cryptic species complex consisting of at least 14 closely related species. Results We found an unexpectedly high variation in this species complex, with genome sizes ranging approximately seven-fold (haploid '1C' genome sizes: 0.056-0.416 pg. Most of this variation (67% could be ascribed to the major clades of the species complex, i.e. clades that are well separated according to most species definitions. However, we also found substantial variation (32% at lower taxonomic levels - within and among genealogical species - and, interestingly, among species pairs that are not completely reproductively isolated. In one genealogical species, called B. 'Austria', we found greatly enlarged genome sizes that could roughly be approximated as multiples of the genomes of its closest relatives, which suggests that whole-genome duplications have occurred early during separation of this lineage. Overall, genome size was significantly correlated to egg size and body size, even though the latter became non-significant after controlling for phylogenetic non-independence. Conclusions Our study suggests that substantial genome size variation can build up early during speciation, potentially even among isolated populations. An alternative, but not mutually exclusive interpretation might be that reproductive isolation tends to build up unusually slow in this species complex.

  9. Systematics of the Osteocephalus buckleyi species complex (Anura, Hylidae from Ecuador and Peru

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    Santiago Ron

    2012-10-01

    Full Text Available We present a new phylogeny, based on DNA sequences of mitochondrial and nuclear genes, for frogs of the genus Osteocephalus with emphasis in the Osteocephalus buckleyi species complex. Genetic, morphologic, and advertisement call data are combined to define species boundaries and describe new species. The phylogeny shows strong support for: (1 a basal position of O. taurinus + O. oophagus, (2 a clade containing phytotelmata breeding species, and (3 a clade that corresponds to the O. buckleyi species complex. Our results document a large proportion of hidden diversity within a set of populations that were previously treated as a single, widely distributed species, O. buckleyi. Individuals assignable to O. buckleyi formed a paraphyletic group relative to O. verruciger and O. cabrerai and contained four species, one of which is O. buckleyi sensu stricto and three are new. Two of the new species are shared between Ecuador and Peru (O. vilmae sp. n. and O. cannatellai sp. n. and one is distributed in the Amazon region of southern Peru (O. germani sp. n.. We discuss the difficulties of using morphological characters to define species boundaries and propose a hypothesis to explain them.

  10. Systematics of the Osteocephalus buckleyi species complex (Anura, Hylidae) from Ecuador and Peru

    Science.gov (United States)

    Ron, Santiago R.; Venegas, Pablo J.; Toral, Eduardo; Morley Read; Diego A. Ortiz; Manzano, Andrea L.

    2012-01-01

    Abstract We present a new phylogeny, based on DNA sequences of mitochondrial and nuclear genes, for frogs of the genus Osteocephalus with emphasis in the Osteocephalus buckleyi species complex. Genetic, morphologic, and advertisement call data are combined to define species boundaries and describe new species. The phylogeny shows strong support for: (1) a basal position of Osteocephalus taurinus + Osteocephalus oophagus, (2) a clade containing phytotelmata breeding species, and (3) a clade that corresponds to the Osteocephalus buckleyi species complex. Our results document a large proportion of hidden diversity within a set of populations that were previously treated as a single, widely distributed species, Osteocephalus buckleyi. Individuals assignable to Osteocephalus buckleyi formed a paraphyletic group relative to Osteocephalus verruciger and Osteocephalus cabrerai and contained four species, one of which is Osteocephalus buckleyi sensu stricto and three are new. Two of the new species are shared between Ecuador and Peru (Osteocephalus vilmae sp. n. and Osteocephalus cannatellai sp. n.) and one is distributed in the Amazon region of southern Peru (Osteocephalus germani sp. n.) We discuss the difficulties of using morphological characters to define species boundaries and propose a hypothesis to explain them. PMID:23166473

  11. The arms race between tomato and Fusarium oxysporum.

    Science.gov (United States)

    Takken, Frank; Rep, Martijn

    2010-03-01

    The interaction between tomato and Fusarium oxysporum f. sp. lycopersici has become a model system for the study of the molecular basis of disease resistance and susceptibility. Gene-for-gene interactions in this system have provided the basis for the development of tomato cultivars resistant to Fusarium wilt disease. Over the last 6 years, new insights into the molecular basis of these gene-for-gene interactions have been obtained. Highlights are the identification of three avirulence genes in F. oxysporum f. sp. lycopersici and the development of a molecular switch model for I-2, a nucleotide-binding and leucine-rich repeat-type resistance protein which mediates the recognition of the Avr2 protein. We summarize these findings here and present possible scenarios for the ongoing molecular arms race between tomato and F. oxysporum f. sp. lycopersici in both nature and agriculture.

  12. Botrytis californica, a new cryptic species in the B. cinerea species complex causing gray mold in blueberries and table grapes.

    Science.gov (United States)

    Saito, S; Margosan, D; Michailides, T J; Xiao, C L

    2016-01-01

    The Botrytis cinerea species complex comprises two cryptic species, originally referred to Group I and Group II based on Bc-hch gene RFLP haplotyping. Group I was described as a new cryptic species B. pseudocinerea During a survey of Botrytis spp. causing gray mold in blueberries and table grapes in the Central Valley of California, six isolates, three from blueberries and three from table grapes, were placed in Group I but had a distinct morphological character with conidiophores significantly longer than those of B. cinerea and B. pseudocinerea We compared these with B. cinerea and B. pseudocinerea by examining morphological and physiological characters, sensitivity to fenhexamid and phylogenetic analysis inferred from sequences of three nuclear genes. Phylogenetic analysis with the three partial gene sequences encoding glyceraldehyde-3-phosate dehydrogenase (G3PDH), heat-shock protein 60 (HSP60) and DNA-dependent RNA polymerase subunit II (RPB2) supported the proposal of a new Botrytis species, B. californica, which is closely related genetically to B. cinerea, B. pseudocinerea and B. sinoviticola, all known as causal agents of gray mold of grapes. Botrytis californica caused decay on blueberry and table grape fruit inoculated with the fungus. This study suggests that B. californica is a cryptic species sympatric with B. cinerea on blueberries and table grapes in California. © 2016 by The Mycological Society of America.

  13. Molecular characterization of Anopheles fluviatilis species complex in the Islamic Republic of Iran.

    Science.gov (United States)

    Naddaf, S R; Oshaghi, M A; Vatandoost, H; Assmar, M

    2003-05-01

    A species-specific polymerase chain reaction (PCR) assay was used to identify the species composition of the Anopheles fluviatilis complex in the Islamic Republic of Iran. All the amplified DNA samples from specimens collected from different areas yielded a fragment of 450 bp size, a PCR product corresponding to that of the species denoted as Y. The sequence data from 21 ITS2 [second internal transcribed spacer] regions were compared with those publicly available in the GenBank database and confirmed that the specimens were 100% identical to species Y of India. Species Y is presumably the same as species T that has no role in transmission of malaria in India, whereas An. fluviatilis is known as a secondary vector of malaria in the Islamic Republic of Iran.

  14. What do we gain from simplicity versus complexity in species distribution models?

    Science.gov (United States)

    Merow, Cory; Smith, Matthew J.; Edwards, Thomas C.; Guisan, Antoine; McMahon, Sean M.; Normand, Signe; Thuiller, Wilfried; Wuest, Rafael O.; Zimmermann, Niklaus E.; Elith, Jane

    2014-01-01

    Species distribution models (SDMs) are widely used to explain and predict species ranges and environmental niches. They are most commonly constructed by inferring species' occurrence–environment relationships using statistical and machine-learning methods. The variety of methods that can be used to construct SDMs (e.g. generalized linear/additive models, tree-based models, maximum entropy, etc.), and the variety of ways that such models can be implemented, permits substantial flexibility in SDM complexity. Building models with an appropriate amount of complexity for the study objectives is critical for robust inference. We characterize complexity as the shape of the inferred occurrence–environment relationships and the number of parameters used to describe them, and search for insights into whether additional complexity is informative or superfluous. By building ‘under fit’ models, having insufficient flexibility to describe observed occurrence–environment relationships, we risk misunderstanding the factors shaping species distributions. By building ‘over fit’ models, with excessive flexibility, we risk inadvertently ascribing pattern to noise or building opaque models. However, model selection can be challenging, especially when comparing models constructed under different modeling approaches. Here we argue for a more pragmatic approach: researchers should constrain the complexity of their models based on study objective, attributes of the data, and an understanding of how these interact with the underlying biological processes. We discuss guidelines for balancing under fitting with over fitting and consequently how complexity affects decisions made during model building. Although some generalities are possible, our discussion reflects differences in opinions that favor simpler versus more complex models. We conclude that combining insights from both simple and complex SDM building approaches best advances our knowledge of current and future species

  15. Colour patterns do not diagnose species: quantitative evaluation of a DNA barcoded cryptic bumblebee complex.

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    James C Carolan

    Full Text Available Cryptic diversity within bumblebees (Bombus has the potential to undermine crucial conservation efforts designed to reverse the observed decline in many bumblebee species worldwide. Central to such efforts is the ability to correctly recognise and diagnose species. The B. lucorum complex (Bombus lucorum, B. cryptarum and B. magnus comprises one of the most abundant and important group of wild plant and crop pollinators in northern Europe. Although the workers of these species are notoriously difficult to diagnose morphologically, it has been claimed that queens are readily diagnosable from morphological characters. Here we assess the value of colour-pattern characters in species identification of DNA-barcoded queens from the B. lucorum complex. Three distinct molecular operational taxonomic units were identified each representing one species. However, no uniquely diagnostic colour-pattern character state was found for any of these three molecular units and most colour-pattern characters showed continuous variation among the units. All characters previously deemed to be unique and diagnostic for one species were displayed by specimens molecularly identified as a different species. These results presented here raise questions on the reliability of species determinations in previous studies and highlights the benefits of implementing DNA barcoding prior to ecological, taxonomic and conservation studies of these important key pollinators.

  16. The current status of the Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) species complex.

    Science.gov (United States)

    Souza, Nataly A; Brazil, Reginaldo P; Araki, Alejandra S

    2017-03-01

    Lutzomyia longipalpis s.l. is a complex of sibling species and is the principal vector of American visceral leishmaniasis. The present review summarises the diversity of efforts that have been undertaken to elucidate the number of unnamed species in this species complex and the phylogenetic relationships among them. A wide variety of evidence, including chemical, behavioral and molecular traits, suggests very recent speciation events and complex population structure in this group. Although significant advances have been achieved to date, differential vector capacity and the correlation between structure of parasite and vector populations have yet to be elucidated. Furthermore, increased knowledge about recent epidemiological changes, such as urbanisation, is essential for pursuing effective strategies for sandfly control in the New World.

  17. Species from within the Phytophthora cryptogea complex and related species, P. erythroseptica and P. sansomeana, readily hybridize.

    Science.gov (United States)

    Safaiefarahani, Banafsheh; Mostowfizadeh-Ghalamfarsa, Reza; Hardy, Giles E St J; Burgess, Treena I

    2016-08-01

    During a study on the phylogenetic relationships between species in the Phytophthora cryptogea complex and related species, Phytophthora erythroseptica and Phytophthora sansomeana, 19 hybrid isolates with multiple polymorphisms in the nuclear sequences were observed. Molecular characterization of hybrids was achieved by sequencing three nuclear (internal transcribed spacers, β-tubulin (TUB), heat shock protein 90) and two mitochondrial (cytochrome c oxidase subunit I (coxI), NADH dehydrogenase subunit I (NADH)) gene regions and cloning of the single-copy nuclear gene, TUB. Based on the molecular studies the hybrid isolates belonged to six distinct groups between P. cryptogea, P. erythroseptica, Phytophthora pseudocryptogea, P. sansomeana, and Phytophthora sp. kelmania. In all cases, only a single coxI and NADH allele was detected and nuclear genes were biparentally inherited, suggesting that the hybrids arose from sexual recombination events. Colony morphology, growth rate, cardinal temperatures, breeding system, and morphology of sporangia, oogonia, oospores, and antheridia were also determined. Some morphological differences between the hybrids and the parental species were noted; however, they were not sufficient to reliably distinguish the taxa and DNA markers from nuclear and mitochondrial genes will to be necessary for their identification. The parental species are all important pathogens of agricultural fields that have been transported globally. With the apparent ease of hybridization within this group there is ample opportunity for virulent hybrids to form, perhaps with extended host ranges. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  18. Phylogenomics and species delimitation of a complex radiation of Neotropical suboscine birds (Pachyramphus).

    Science.gov (United States)

    Musher, Lukas J; Cracraft, Joel

    2018-01-01

    Phylogeographic studies within the Neotropics continue to uncover hidden diversity, the extent of which remains poorly known. In birds, molecular studies are producing evidence that species-level diversity is substantially underestimated. Many avian taxa comprise large complexes of subspecies that often represent species-level taxa by various criteria. One such group of Neotropical suboscine birds, the becards (Pachyramphus), ranges from Argentina through northern Mexico. Their taxonomic limits have been complex and controversial as the genus has bounced around a number of suboscine families. Additionally, the phylogenetic relationships within Pachyramphus are unresolved due to insufficient sampling of taxa and populations across species' ranges. We used target capture of ultraconserved elements for 62 individuals representing 42 taxa, and sequenced two mitochondrial genes and two nuclear introns covering 265 individuals of 51 taxa, including all recognized species, resulting in the most densely and completely sampled phylogenetic hypothesis for Pachyramphus to date. We delimited species using a traditional taxonomic approach and then tested them under a Bayesian multi-species coalescent framework. In doing so, we provide evidence for multiple young, previously undetected evolutionary lineages within Pachyramphus. Deep, well-supported branches and a high number of intraspecific lineages across the tree suggest that at least 50% of species diversity may be unrecognized. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Comparative Analysis of Satellite DNA in the Drosophila melanogaster Species Complex

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    Madhav Jagannathan

    2017-02-01

    Full Text Available Satellite DNAs are highly repetitive sequences that account for the majority of constitutive heterochromatin in many eukaryotic genomes. It is widely recognized that sequences and locations of satellite DNAs are highly divergent even in closely related species, contributing to the hypothesis that satellite DNA differences may underlie speciation. However, due to its repetitive nature, the mapping of satellite DNAs has been mostly left out of recent genomics analyses, hampering the use of molecular genetics techniques to better understand their role in speciation and evolution. Satellite DNAs are most extensively and comprehensively mapped in Drosophila melanogaster, a species that is also an excellent model system with which to study speciation. Yet the lack of comprehensive knowledge regarding satellite DNA identity and location in its sibling species (D. simulans, D. mauritiana, and D. sechellia has prevented the full utilization of D. melanogaster in studying speciation. To overcome this problem, we initiated the mapping of satellite DNAs on the genomes of the D. melanogaster species complex (D. melanogaster, D. simulans, D. mauritiana, and D. sechellia using multi-color fluorescent in situ hybridization (FISH probes. Our study confirms a striking divergence of satellite DNAs in the D. melanogaster species complex, even among the closely related species of the D. simulans clade (D. simulans, D. mauritiana, and D. sechellia, and suggests the presence of unidentified satellite sequences in these species.

  20. Suppressor of fusion, a Fusarium oxysporum homolog of Ndt80, is required for nutrient-dependent regulation of anastomosis.

    Science.gov (United States)

    Shahi, Shermineh; Fokkens, Like; Houterman, Petra M; Rep, Martijn

    2016-10-01

    Heterokaryon formation is an essential step in asexual recombination in Fusarium oxysporum. Filamentous fungi have an elaborate nonself recognition machinery to prevent formation and proliferation of heterokaryotic cells, called heterokaryon incompatibility (HI). In F. oxysporum the regulation of this machinery is not well understood. In Neurospora crassa, Vib-1, a putative transcription factor of the p53-like Ndt80 family of transcription factors, has been identified as global regulator of HI. In this study we investigated the role of the F. oxysporum homolog of Vib-1, called Suf, in vegetative hyphal and conidial anastomosis tube (CAT) fusion and HI. We identified a novel function for an Ndt80 homolog as a nutrient-dependent regulator of anastomosis. Strains carrying the SUF deletion mutation display a hyper-fusion phenotype during vegetative growth as well as germling development. In addition, conidial paring of incompatible SUF deletion strains led to more heterokaryon formation, which is independent of suppression of HI. Our data provides further proof for the divergence in the functions of different members Ndt80 family. We propose that Ndt80 homologs mediate responses to nutrient quality and quantity, with specific responses varying between species. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Molecular Phylogeny and Zoogeography of the Capoeta damascina Species Complex (Pisces: Teleostei: Cyprinidae.

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    Nisreen Alwan

    Full Text Available Capoeta damascina was earlier considered by many authors as one of the most common freshwater fish species found throughout the Levant, Mesopotamia, Turkey, and Iran. However, owing to a high variation in morphological characters among and within its various populations, 17 nominal species were described, several of which were regarded as valid by subsequent revising authors. Capoeta damascina proved to be a complex of closely related species, which had been poorly studied. The current study aims at defining C. damascina and the C. damascina species complex. It investigates phylogenetic relationships among the various members of the C. damascina complex, based on mitochondrial and nuclear DNA sequences. Phylogenetic relationships were projected against paleogeographical events to interpret the geographic distribution of the taxa under consideration in relation to the area's geological history. Samples were obtained from throughout the geographic range and were subjected to genetic analyses, using two molecular markers targeting the mitochondrial cytochrome oxidase I (n = 103 and the two adjacent divergence regions (D1-D2 of the nuclear 28S rRNA genes (n = 65. Six closely related species were recognized within the C. damascina complex, constituting two main lineages: A western lineage represented by C. caelestis, C. damascina, and C. umbla and an eastern lineage represented by C. buhsei, C. coadi, and C. saadii. The results indicate that speciation of these taxa is rather a recent event. Dispersal occurred during the Pleistocene, resulting in present-day distribution patterns. A coherent picture of the phylogenetic relationships and evolutionary history of the C. damascina species complex is drawn, explaining the current patterns of distribution as a result of paleogeographic events and ecological adaptations.

  2. Molecular Phylogeny and Zoogeography of the Capoeta damascina Species Complex (Pisces: Teleostei: Cyprinidae).

    Science.gov (United States)

    Alwan, Nisreen; Esmaeili, Hamid-Reza; Krupp, Friedhelm

    2016-01-01

    Capoeta damascina was earlier considered by many authors as one of the most common freshwater fish species found throughout the Levant, Mesopotamia, Turkey, and Iran. However, owing to a high variation in morphological characters among and within its various populations, 17 nominal species were described, several of which were regarded as valid by subsequent revising authors. Capoeta damascina proved to be a complex of closely related species, which had been poorly studied. The current study aims at defining C. damascina and the C. damascina species complex. It investigates phylogenetic relationships among the various members of the C. damascina complex, based on mitochondrial and nuclear DNA sequences. Phylogenetic relationships were projected against paleogeographical events to interpret the geographic distribution of the taxa under consideration in relation to the area's geological history. Samples were obtained from throughout the geographic range and were subjected to genetic analyses, using two molecular markers targeting the mitochondrial cytochrome oxidase I (n = 103) and the two adjacent divergence regions (D1-D2) of the nuclear 28S rRNA genes (n = 65). Six closely related species were recognized within the C. damascina complex, constituting two main lineages: A western lineage represented by C. caelestis, C. damascina, and C. umbla and an eastern lineage represented by C. buhsei, C. coadi, and C. saadii. The results indicate that speciation of these taxa is rather a recent event. Dispersal occurred during the Pleistocene, resulting in present-day distribution patterns. A coherent picture of the phylogenetic relationships and evolutionary history of the C. damascina species complex is drawn, explaining the current patterns of distribution as a result of paleogeographic events and ecological adaptations.

  3. Comparison of transcriptome profiles by Fusarium oxysporum inoculation between Fusarium yellows resistant and susceptible lines in Brassica rapa L.

    Science.gov (United States)

    Miyaji, Naomi; Shimizu, Motoki; Miyazaki, Junji; Osabe, Kenji; Sato, Maho; Ebe, Yusuke; Takada, Satoko; Kaji, Makoto; Dennis, Elizabeth S; Fujimoto, Ryo; Okazaki, Keiichi

    2017-12-01

    Resistant and susceptible lines in Brassica rapa have different immune responses against Fusarium oxysporum inoculation. Fusarium yellows caused by Fusarium oxysporum f. sp. conglutinans (Foc) is an important disease of Brassicaceae; however, the mechanism of how host plants respond to Foc is still unknown. By comparing with and without Foc inoculation in both resistant and susceptible lines of Chinese cabbage (Brassica rapa var. pekinensis), we identified differentially expressed genes (DEGs) between the bulked inoculated (6, 12, 24, and 72 h after inoculation (HAI)) and non-inoculated samples. Most of the DEGs were up-regulated by Foc inoculation. Quantitative real-time RT-PCR showed that most up-regulated genes increased their expression levels from 24 HAI. An independent transcriptome analysis at 24 and 72 HAI was performed in resistant and susceptible lines. GO analysis using up-regulated genes at 24 HAI indicated that Foc inoculation activated systemic acquired resistance (SAR) in resistant lines and tryptophan biosynthetic process and responses to chitin and ethylene in susceptible lines. By contrast, GO analysis using up-regulated genes at 72 HAI showed the overrepresentation of some categories for the defense response in susceptible lines but not in the resistant lines. We also compared DEGs between B. rapa and Arabidopsis thaliana after F. oxysporum inoculation at the same time point, and identified genes related to defense response that were up-regulated in the resistant lines of Chinese cabbage and A. thaliana. Particular genes that changed expression levels overlapped between the two species, suggesting that they are candidates for genes involved in the resistance mechanisms against F. oxysporum.

  4. Genetic networking of the Bemisia tabaci cryptic species complex reveals pattern of biological invasions.

    Directory of Open Access Journals (Sweden)

    Paul De Barro

    Full Text Available BACKGROUND: A challenge within the context of cryptic species is the delimitation of individual species within the complex. Statistical parsimony network analytics offers the opportunity to explore limits in situations where there are insufficient species-specific morphological characters to separate taxa. The results also enable us to explore the spread in taxa that have invaded globally. METHODOLOGY/PRINCIPAL FINDINGS: Using a 657 bp portion of mitochondrial cytochrome oxidase 1 from 352 unique haplotypes belonging to the Bemisia tabaci cryptic species complex, the analysis revealed 28 networks plus 7 unconnected individual haplotypes. Of the networks, 24 corresponded to the putative species identified using the rule set devised by Dinsdale et al. (2010. Only two species proposed in Dinsdale et al. (2010 departed substantially from the structure suggested by the analysis. The analysis of the two invasive members of the complex, Mediterranean (MED and Middle East - Asia Minor 1 (MEAM1, showed that in both cases only a small number of haplotypes represent the majority that have spread beyond the home range; one MEAM1 and three MED haplotypes account for >80% of the GenBank records. Israel is a possible source of the globally invasive MEAM1 whereas MED has two possible sources. The first is the eastern Mediterranean which has invaded only the USA, primarily Florida and to a lesser extent California. The second are western Mediterranean haplotypes that have spread to the USA, Asia and South America. The structure for MED supports two home range distributions, a Sub-Saharan range and a Mediterranean range. The MEAM1 network supports the Middle East - Asia Minor region. CONCLUSION/SIGNIFICANCE: The network analyses show a high level of congruence with the species identified in a previous phylogenetic analysis. The analysis of the two globally invasive members of the complex support the view that global invasion often involve very small portions of

  5. Antagonistic Activities of Novel Peptides from Bacillus amyloliquefaciens PT14 against Fusarium solani and Fusarium oxysporum.

    Science.gov (United States)

    Kim, Young Gwon; Kang, Hee Kyoung; Kwon, Kee-Deok; Seo, Chang Ho; Lee, Hyang Burm; Park, Yoonkyung

    2015-12-09

    Bacillus species have recently drawn attention due to their potential use in the biological control of fungal diseases. This paper reports on the antifungal activity of novel peptides isolated from Bacillus amyloliquefaciens PT14. Reverse-phase high-performance liquid chromatography revealed that B. amyloliquefaciens PT14 produces five peptides (PT14-1, -2, -3, -4a, and -4b) that exhibit antifungal activity but are inactive against bacterial strains. In particular, PT14-3 and PT14-4a showed broad-spectrum antifungal activity against Fusarium solani and Fusarium oxysporum. The PT14-4a N-terminal amino acid sequence was identified through Edman degradation, and a BLAST homology analysis showed it not to be identical to any other protein or peptide. PT14-4a displayed strong fungicidal activity with minimal inhibitory concentrations of 3.12 mg/L (F. solani) and 6.25 mg/L (F. oxysporum), inducing severe morphological deformation in the conidia and hyphae. On the other hand, PT14-4a had no detectable hemolytic activity. This suggests PT14-4a has the potential to serve as an antifungal agent in clinical therapeutic and crop-protection applications.

  6. Quantum mechanical calculation of aqueuous uranium complexes: carbonate, phosphate, organic and biomolecular species

    Directory of Open Access Journals (Sweden)

    Jha Prashant

    2009-08-01

    Full Text Available Abstract Background Quantum mechanical calculations were performed on a variety of uranium species representing U(VI, U(V, U(IV, U-carbonates, U-phosphates, U-oxalates, U-catecholates, U-phosphodiesters, U-phosphorylated N-acetyl-glucosamine (NAG, and U-2-Keto-3-doxyoctanoate (KDO with explicit solvation by H2O molecules. These models represent major U species in natural waters and complexes on bacterial surfaces. The model results are compared to observed EXAFS, IR, Raman and NMR spectra. Results Agreement between experiment and theory is acceptable in most cases, and the reasons for discrepancies are discussed. Calculated Gibbs free energies are used to constrain which configurations are most likely to be stable under circumneutral pH conditions. Reduction of U(VI to U(IV is examined for the U-carbonate and U-catechol complexes. Conclusion Results on the potential energy differences between U(V- and U(IV-carbonate complexes suggest that the cause of slower disproportionation in this system is electrostatic repulsion between UO2 [CO3]35- ions that must approach one another to form U(VI and U(IV rather than a change in thermodynamic stability. Calculations on U-catechol species are consistent with the observation that UO22+ can oxidize catechol and form quinone-like species. In addition, outer-sphere complexation is predicted to be the most stable for U-catechol interactions based on calculated energies and comparison to 13C NMR spectra. Outer-sphere complexes (i.e., ion pairs bridged by water molecules are predicted to be comparable in Gibbs free energy to inner-sphere complexes for a model carboxylic acid. Complexation of uranyl to phosphorus-containing groups in extracellular polymeric substances is predicted to favor phosphonate groups, such as that found in phosphorylated NAG, rather than phosphodiesters, such as those in nucleic acids.

  7. How to conquer a tomato plant? Fusarium oxysporum effector targets

    NARCIS (Netherlands)

    de Sain, M.

    2016-01-01

    Pathogens secrete small proteins, called effectors, to alter the environment in their host to facilitate infection. The causal agent of Fusarium wilt on tomato, Fusarium oxysporum f. sp. lycopersici (Fol), secretes these proteins in the xylem sap of infected plants and hence they have been called

  8. Effect of endophytic Fusarium oxysporum on paralysis and mortality ...

    African Journals Online (AJOL)

    Three bioassays were conducted to investigate the antagonistic effect of secondary metabolites produced by 5 endophytic Fusarium oxysporum isolates from banana (Musa spp.) plants in Kenya, against Pratylenchus goodeyi. Percentage paralyses were recorded 3, 6 and 24 h after exposure to culture filtrates. Percentage ...

  9. Biochemical characterization of Fusarium oxysporum f. sp. cubense ...

    African Journals Online (AJOL)

    PRECIOUS

    2010-01-25

    Jan 25, 2010 ... qualities such as taste, aroma, color, fibrous texture and nutritional content. It has a .... instance two proteins of molecular weight 51.9 and 43.0. kDa were detected only .... Earlier investigations support this view in F. oxysporum f. sp. apii ... Comparison of multi-locus enzyme and protein gel electrophoresis in.

  10. Purification and characterization of xylitol dehydrogenase from Fusarium oxysporum

    DEFF Research Database (Denmark)

    Panagiotou, Gianni; Kekos, D.; Macris, B.J.

    2002-01-01

    An NAD(+)-dependent xylitol dehydrogenase (XDH) from Fusarium oxysporum, a key enzyme in the conversion of xylose to ethanol, was purified to homogeneity and characterised. It was homodimeric with a subunit of M-r 48 000, and pI 3.6. It was optimally active at 45degreesC and pH 9-10. It was fully...

  11. The arms race between tomato and Fusarium oxysporum

    NARCIS (Netherlands)

    Takken, F.; Rep, M.

    2010-01-01

    The interaction between tomato and Fusarium oxysporum f. sp. lycopersici has become a model system for the study of the molecular basis of disease resistance and susceptibility. Gene-for-gene interactions in this system have provided the basis for the development of tomato cultivars resistant to

  12. Oxygen requirement for denitrification by the fungus Fusarium oxysporum.

    Science.gov (United States)

    Zhou, Z; Takaya, N; Sakairi, M A; Shoun, H

    2001-01-01

    The effects of dioxygen (O2) on the denitrification activity of the fungus Fusarium oxysporum MT-811 in fed-batch culture in a stirred jar fermentor were examined. The results revealed that fungal denitrifying activity requires a minimal amount of O2 for induction, which is repressed by excess O2. The optimal O2 supply differed between the denitrification substrates : 690 micromol O2 x h(-1) (g dry cell wt.)(-1) for nitrate (NO3-) and about 250 micromol O2 x h(-1) (g dry cell wt.)(-1) for nitrite (NO2-). The reduction of NO3- required more O2 than that of NO2- . With an optimal O2 supply, 80% and 52% of nitrogen atoms in NO3- and NO2-, respectively, were recovered as the denitrification product N2O. These features of F. oxysporum differ from those of bacterial denitrifiers that work exclusively under anoxic conditions. The denitrification activity of F. oxysporum MT-811 mutants with impaired NO3- assimilation was about double that of the wild-type strain, suggesting competition for the substrate between assimilatory and dissimilatory types of NO3- reduction. These results showed that denitrification by F. oxysporum has unique features, namely, a minimal O2 requirement and competition with assimilatory NO3-.

  13. Purification of phytotoxic metabolites from culture filtrate of Fusarium oxysporum f. sp. cubense gcv 01210 (race 1

    Directory of Open Access Journals (Sweden)

    Nayanci Portal

    2011-04-01

    Full Text Available Panama disease, caused by Fusarium oxysporum f. sp. cubense, is considered a destructive disease of economic importance in the genus Musa. The culture filtrates of the pathogen have been used to differentiate cultivars, but have not been identified metabolites involved in the differential response. The aim of this study was to purify phytotoxic metabolites present in the culture filtrate of Fusarium oxysporum f. sp. cubense GCV [01210] Race 1 for further chemical characterization. We used a culture filtrate of 15 days of incubation. The phytotoxic activity was tested with a leaf bioassay on the susceptible cultivar ‘Gros Michel’ and resistant ‘FHIA 01’. The organic extract was extracted and fractionated. It was partitioned with organic solvents of rising polarity and found the complexity of each of the fractions by TLC. The metabolites were purified by flash column chromatography. Two compounds were purified from the culture filtrate of the pathogen which not only differed in color (blue and pale yellow, but also in polarity. Fractions B (containing blue compound and E (containing yellow compound produced significant differences in lesion area between resistant and susceptible cultivar. These results are not conclusive but, it is the basis for the identification of compounds involved in the differential response of Musa spp. cultivars to the culture filtrate of Fusarium oxysporum f. sp. cubense. Key Words: phytotoxic activity, chromatography, organic extract, Panama disease, plantains and bananas

  14. A revision of the Schinia Volupia (Fitch) species complex Lepidoptera: Noctuidae: Heliothinae)

    Science.gov (United States)

    DNA barcode analysis of cytochrome oxidase I (COI) could not differentiate between the species of the Schinia volupia (Fitch) complex including, S. volupia, S. masoni Smith, S. fulleri (McElvare), S. sanrafaeli (Opler), S. miniana (Grote), and S. biforma Smith. Genitalic characters could only differ...

  15. Morphological and molecular characterization of Cladosporium cladosporioides species complex causing pecan tree leaf spot.

    Science.gov (United States)

    Walker, C; Muniz, M F B; Rolim, J M; Martins, R R O; Rosenthal, V C; Maciel, C G; Mezzomo, R; Reiniger, L R S

    2016-09-16

    The objective of this study was to characterize species of the Cladosporium cladosporioides complex isolated from pecan trees (Carya illinoinensis) with symptoms of leaf spot, based on morphological and molecular approaches. Morphological attributes were assessed using monosporic cultures on potato dextrose agar medium, which were examined for mycelial growth, sporulation, color, and conidia and ramoconidia size. Molecular characterization comprised isolation of DNA and subsequent amplification of the translation elongation factor 1α (TEF-1α) region. Three species of the C. cladosporioides complex were identified: C. cladosporioides, Cladosporium pseudocladosporioides, and Cladosporium subuliforme. Sporulation was the most important characteristic differentiating species of this genus. However, morphological features must be considered together with molecular analysis, as certain characters are indistinguishable between species. TEF-1αcan be effectively used to identify and group isolates belonging to the C. cladosporioides complex. The present study provides an important example of a methodology to ascertain similarity between isolates of this complex causing leaf spot in pecan trees, which should facilitate future pathogenicity studies.

  16. Geographically predominant genotypes of Aspergillus terreus species complex in Austria: s microsatellite typing study

    NARCIS (Netherlands)

    Lackner, M.; Coassin, S.; Haun, M.; Binder, U.; Kronenberg, F.; Haas, H. de; Jank, M.; Maurer, E.; Meis, J.F.; Hagen, F.; Lass-Florl, C.

    2016-01-01

    Aspergillus terreus species complex is recognized as a frequent agent of invasive aspergillosis in Tyrol. The reason for this specific epidemiological situation is unclear. Aspergillus terreus strains isolated from environmental and clinical sources were genotyped using a novel panel of short tandem

  17. Delineation of a New Species of the Borrelia burgdorferi Sensu Lato Complex, Borrelia americana sp. nov

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Lin, T.; Gao, L.; Grubhoffer, Libor; Oliver, J. H., Jr.

    2009-01-01

    Roč. 47, č. 12 (2009), s. 3875-3880 ISSN 0095-1137 R&D Projects: GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : multilocus sequence analysis * B. burgdorferi sl complex * new borrelia species * Borrelia americana Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 4.162, year: 2009

  18. Ultrastructural characteristics of nurse cell-larva complex of four species of Trichinella in several hosts

    Directory of Open Access Journals (Sweden)

    Sacchi L.

    2001-06-01

    Full Text Available The nurse cell-larva complex of nematodes of the genus Trichinella plays an Important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. The ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with T. nativa (a walrus and a polar bear, T. spiralis (horses and humans, T. pseudospiralis (a laboratory mouse and T. papuae (a laboratory mouse were examined. Analysis with transmission electron microscope showed that the typical nurse cell structure was present in all examined samples, irrespective of the species of larva, of the presence of a collagen capsule, of the age of infection and of the host species, suggesting that there exists a molecular mechanism that in the first stage of larva invasion is similar for encapsulated and non-encapsulated species.

  19. Comparative transcriptome analysis within the Lolium/Festuca species complex reveals high sequence conservation

    DEFF Research Database (Denmark)

    Czaban, Adrian; Sharma, Sapna; Byrne, Stephen

    2015-01-01

    species from the Lolium-Festuca complex, ranging from 52,166 to 72,133 transcripts per assembly. We have also predicted a set of proteins and validated it with a high-confidence protein database from three closely related species (H. vulgare, B. distachyon and O. sativa). We have obtained gene family...... clusters for the four species using OrthoMCL and analyzed their inferred phylogenetic relationships. Our results indicate that VRN2 is a candidate gene for differentiating vernalization and non-vernalization types in the Lolium-Festuca complex. Grouping of the gene families based on their BLAST identity...... enabled us to divide ortholog groups into those that are very conserved and those that are more evolutionarily relaxed. The ratio of the non-synonumous to synonymous substitutions enabled us to pinpoint protein sequences evolving in response to positive selection. These proteins may explain some...

  20. DNA Barcode Analysis of Thrips (Thysanoptera) Diversity in Pakistan Reveals Cryptic Species Complexes.

    Science.gov (United States)

    Iftikhar, Romana; Ashfaq, Muhammad; Rasool, Akhtar; Hebert, Paul D N

    2016-01-01

    Although thrips are globally important crop pests and vectors of viral disease, species identifications are difficult because of their small size and inconspicuous morphological differences. Sequence variation in the mitochondrial COI-5' (DNA barcode) region has proven effective for the identification of species in many groups of insect pests. We analyzed barcode sequence variation among 471 thrips from various plant hosts in north-central Pakistan. The Barcode Index Number (BIN) system assigned these sequences to 55 BINs, while the Automatic Barcode Gap Discovery detected 56 partitions, a count that coincided with the number of monophyletic lineages recognized by Neighbor-Joining analysis and Bayesian inference. Congeneric species showed an average of 19% sequence divergence (range = 5.6% - 27%) at COI, while intraspecific distances averaged 0.6% (range = 0.0% - 7.6%). BIN analysis suggested that all intraspecific divergence >3.0% actually involved a species complex. In fact, sequences for three major pest species (Haplothrips reuteri, Thrips palmi, Thrips tabaci), and one predatory thrips (Aeolothrips intermedius) showed deep intraspecific divergences, providing evidence that each is a cryptic species complex. The study compiles the first barcode reference library for the thrips of Pakistan, and examines global haplotype diversity in four important pest thrips.

  1. Characterization and regulation of glycine transport in Fusarium oxysporum var. lini.

    Science.gov (United States)

    Castro, I M; Lima, A A; Nascimento, A F; Ruas, M M; Nicoli, J R; Brandão, R L

    1996-08-01

    Glycine was transported in Fusarium oxysporum cells, grown on glycine as the sole source of carbon and nitrogen, by a facilitated diffusion transport system with a half-saturation constant (Ks) of 11 mM and a maximum velocity (Vmax) of 1.2 mM (g dry weight)-1 h-1 at pH 5.0 and 26 degrees C. Under conditions of nitrogen starvation, the same system was present together with a high-affinity one (Ks) of about 47 microM and Vmax of about 60 microM (g dry weight)-1 h-1). The low-affinity system was more specific than the high-affinity system. Cells grown on gelatine showed the same behavior. In cells grown on glucose-gelatine medium, the low-affinity system was poorly expressed even after carbon and nitrogen starvation. Moreover, addition of glucose to cells grown on glycine and resuspended in mineral medium caused an increase of the glycine transport probably due to a boost in protein synthesis. This stimulation did not affect the Ks of the low-affinity system. These results demonstrate that, as is the case for other eukaryotic systems, F. oxysporum glycine transport is under control of nitrogen sources but its regulation by carbon sources appears to be more complex.

  2. Lutzomyia longipalpis in Brazil: a complex or a single species? A mini-review

    Directory of Open Access Journals (Sweden)

    Luiz GSR Bauzer

    2007-02-01

    Full Text Available Lutzomyia longipalpis is the main vector of Leishmania infantum chagasi, the causative agent of American visceral leishmaniasis (AVL. Although there is strong evidence that Lu. longipalpis is a species complex, not all data concerning populations from Brazil support this hypothesis. The issue is still somewhat controversial for this large part of Lu. longipalpis distribution range even though that it is the Latin American region contributing to most of the cases of AVL. In this mini-review we consider in detail the current data for the Brazilian populations and conclude that Lu. longipalpis is a complex of incipient vector species with a complexity similar to Anopheles gambiae s.s. in Africa.

  3. Identification of the non-pertechnetate species in Hanford waste tanks, Tc(I) carbonyl complexes

    Energy Technology Data Exchange (ETDEWEB)

    Lukens, Wayne W.; Shuh, David K.; Schroeder, Norman C.; Ashley, Kenneth R.

    2003-10-16

    Immobilization of the high-level nuclear waste stored at the Hanford Reservation has been complicated by the presence of soluble, lower-valent technetium species. Previous work by Schroeder and Blanchard has shown that these species cannot be removed by ion-exchange and are difficult to oxidize. The Tc-K edge XANES spectra of the species in Tanks SY-101 and SY-103 were reported by Blanchard, but they could not be assigned to any known technetium complex. We report that the XANES spectra are most likely those of Tc(I) carbonyl species, especially fac-Tc(CO){sub 3}(gluconate){sup 2-}. This is further supported by EXAFS and {sup 99}Tc-NMR studies in nonradioactive simulants of these tank wastes.

  4. Molecular phylogenetics and historical biogeography of the west-palearctic common toads (Bufo bufo species complex).

    Science.gov (United States)

    Garcia-Porta, J; Litvinchuk, S N; Crochet, P A; Romano, A; Geniez, P H; Lo-Valvo, M; Lymberakis, P; Carranza, S

    2012-04-01

    In most pan-Eurasiatic species complexes, two phenomena have been traditionally considered key processes of their cladogenesis and biogeography. First, it is hypothesized that the origin and development of the Central Asian Deserts generated a biogeographic barrier that fragmented past continuous distributions in Eastern and Western domains. Second, Pleistocene glaciations have been proposed as the main process driving the regional diversification within each of these domains. The European common toad and its closest relatives provide an interesting opportunity to examine the relative contributions of these paleogeographic and paleoclimatic events to the phylogeny and biogeography of a widespread Eurasiatic group. We investigate this issue by applying a multiproxy approach combining information from molecular phylogenies, a multiple correspondence analysis of allozyme data and species distribution models. Our study includes 304 specimens from 164 populations, covering most of the distributional range of the Bufo bufo species complex in the Western Palearctic. The phylogenies (ML and Bayesian analyses) were based on a total of 1988 bp of mitochondrial DNA encompassing three genes (tRNAval, 16S and ND1). A dataset with 173 species of the family Bufonidae was assembled to estimate the separation of the two pan-Eurasiatic species complexes of Bufo and to date the main biogeographic events within the Bufo bufo species complex. The allozyme study included sixteen protein systems, corresponding to 21 presumptive loci. Finally, the distribution models were based on maximum entropy. Our distribution models show that Eastern and Western species complexes are greatly isolated by the Central Asian Deserts, and our dating estimates place this divergence during the Middle Miocene, a moment in which different sources of evidence document a major upturn of the aridification rate of Central Asia. This climate-driven process likely separated the Eastern and Western species. At the

  5. Neckteeth formation in two species of the Daphnia curvirostris complex (Crustacea: Cladocera

    Directory of Open Access Journals (Sweden)

    Petr Jan JURAČKA

    2011-08-01

    Full Text Available Cladocerans of the genus Daphnia show different morphological adaptations against invertebrate predation. Among those, the formation of neckteeth has attracted substantial attention. Morphotypes exhibiting neckteeth better resist predation from larvae of phantom midges Chaoborus (Diptera. These morphological structures are known from several species of the Daphnia longispina and D. pulex complexes; recently they have also been reported in the D. curvirostris complex, within which they are well documented from the Far East species D. sinevi and from Central European D. hrbaceki. Much scarcer are indications of the formation of these structures in the widespread species D. curvirostris. Careful inspection of samples from pools with Chaoborus larvae nevertheless revealed that a small necktooth in the first few instars of D. curvirostris is not uncommon, but probably has been mostly overlooked in the past. Occasionally, even adult D. curvirostris males may carry this feature. We provide documentation, particularly by scanning electron micrographs, of neckteeth in field-collected D. curvirostris, and in juvenile individuals of its sister species D. hrbaceki. In addition, we tested the response of three clones each of D. curvirostris and D. hrbaceki to Chaoborus kairomones in laboratory experiments. Two clones of the former species and all three of the latter responded to this predator cue with neckteeth formation. First-instar juveniles of D. hrbaceki also occasionally carried neckteeth in control treatments without Chaoborus kairomones, but second and third instars did not. We also observed strong interclonal variation in neonate length in the presence of kairomones in this species. We provide a summary table listing all Daphnia species presently known to exhibit neckteeth, and propose that the ability to form these structures may be more widespread among common Daphnia species than previously assumed.

  6. Integrative taxonomy and preliminary assessment of species limits in the Liolaemus walkeri complex (Squamata, Liolaemidae with descriptions of three new species from Peru

    Directory of Open Access Journals (Sweden)

    Cesar Aguilar

    2013-12-01

    Full Text Available Species delimitation studies based on integrative taxonomic approaches have received considerable attention in the last few years, and have provided the strongest hypotheses of species boundaries. We used three lines of evidence (molecular, morphological, and niche envelopes to test for species boundaries in Peruvian populations of the Liolaemus walkeri complex. Our results show that different lines of evidence and analyses are congruent in different combinations, for unambiguous delimitation of three lineages that were “hidden” within known species, and now deserve species status. Our phylogenetic analysis shows that L. walkeri, L. tacnae and the three new species are strongly separated from other species assigned to the alticolor-bibronii group. Few conventional morphological characters distinguish the new species from closely related taxa and this highlights the need to integrate other sources of data to erect strong hypothesis of species limits. A taxonomic key for known Peruvian species of the subgenus Lioalemus is provided.

  7. The status of the Lutzomyia longipalpis species complex and possible implications for Leishmania transmission

    Directory of Open Access Journals (Sweden)

    Uribe Sandra

    1999-01-01

    Full Text Available The sand fly Lutzomyia longipalpis sensu latu has been identified as the principal vector of American visceral leishmaniasis, a potentially fatal disease that primarily affects children in several countries of South and Central America. Over the past several years increases have occurred both in the number of reported cases and the population at risk: approximately 1.6 million people reside in highly endemic areas with 16,000 cases reported annually. Several studies have attempted to relate the epidemiology of this disease to variability in Lu. longipalpis that is now recognized to be a complex of at least three sibling species. Morphological variation in this species was first noted by Mangabeira (1969. Since then physiological and biochemical differences have been reported by several investigators. Recent reports in Costa Rica of the presence of Lu. longipalpis in a focus of cutaneous leishmaniasis caused by Leishmania chagasi may be an additional indication of variability in this species. While existing evidence indicates that the morphospecies Lu. longipalpis may represent a complex of sibling species, genetic, epidemiological and ecological distinctions have not been fully resolved. Thus, delimitation of systematic boundaries within the complex and corresponding to geographic distributions and roles in transmission remain unresolved. The purpose of this review is to summarize from the literature observations of polymorphism in this morphospecies and consider what significance this reported variability may have to the epidemiology of visceral leishmaniasis.

  8. Speciation in ancient cryptic species complexes: evidence from the molecular phylogeny of Brachionus plicatilis (Rotifera).

    Science.gov (United States)

    Gómez, Africa; Serra, Manuel; Carvalho, Gary R; Lunt, David H

    2002-07-01

    Continental lake-dwelling zooplanktonic organisms have long been considered cosmopolitan species with little geographic variation in spite of the isolation of their habitats. Evidence of morphological cohesiveness and high dispersal capabilities support this interpretation. However, this view has been challenged recently as many such species have been shown either to comprise cryptic species complexes or to exhibit marked population genetic differentiation and strong phylogeographic structuring at a regional scale. Here we investigate the molecular phylogeny of the cosmopolitan passively dispersing rotifer Brachionus plicatilis (Rotifera: Monogononta) species complex using nucleotide sequence variation from both nuclear (ribosomal internal transcribed spacer 1, ITS1) and mitochondrial (cytochrome c oxidase subunit I, COI) genes. Analysis of rotifer resting eggs from 27 salt lakes in the Iberian Peninsula plus lakes from four continents revealed nine genetically divergent lineages. The high level of sequence divergence, absence of hybridization, and extensive sympatry observed support the specific status of these lineages. Sequence divergence estimates indicate that the B. plicatilis complex began diversifying many millions of years ago, yet has showed relatively high levels of morphological stasis. We discuss these results in relation to the ecology and genetics of aquatic invertebrates possessing dispersive resting propagules and address the apparent contradiction between zooplanktonic population structure and their morphological stasis.

  9. Epicuticular chemistry reinforces the new taxonomic classification of the Bactrocera dorsalis species complex (Diptera: Tephritidae, Dacinae)

    Science.gov (United States)

    Vaníčková, Lucie; Nagy, Radka; Pompeiano, Antonio

    2017-01-01

    Bactrocera invadens Drew, Tsuruta & White, Bactrocera papayae Drew & Hancock, and Bactrocera philippinensis Drew & Hancock, key pest species within the Bactrocera dorsalis species complex, have been recently synonymized under the name Bactrocera dorsalis (Hendel). The closely related Bactrocera carambolae Drew & Hancock remains as a discrete taxonomic entity. Although the synonymizations have been accepted by most researchers, debate about the species limits remains. Because of the economic importance of this group of taxa, any new information available to support or deny the synonymizations is valuable. We investigated the chemical epicuticle composition of males and females of B. dorsalis, B. invadens, B. papayae, B. philippinensis, and B. carambolae by means of one- and two-dimensional gas chromatography–mass spectrometry, followed by multiple factor analyses and principal component analysis. Clear segregation of complex cuticule profiles of both B. carambolae sexes from B. dorsalis (Hendel) was observed. In addition to cuticular hydrocarbons, abundant complex mixtures of sex-specific oxygenated lipids (three fatty acids and 22 fatty acid esters) with so far unknown function were identified in epicuticle extracts from females of all species. The data obtained supports both taxonomic synonymization of B. invadens, B. papayae, and B. philippinensis with B. dorsalis, as well as the exclusion of B. carambolae from B. dorsalis. PMID:28873446

  10. A new species of Labidocera (Copepoda, Calanoida, Pontellidae) collected from Okinawa, southwestern Japan, with establishment of five Indo-West Pacific species groups in the L.detruncata species complex.

    Science.gov (United States)

    Hirabayashi, Takeshi; Ohtsuka, Susumu

    2014-01-01

    Labidocerachuraumi sp. n. is described from Okinawa, southwestern Japan. The female of the new species differs from other congeners in genital compound somite with right postero-lateral and left antero-lateral processes. The male is distinguished from other congeners by the structure of the fifth leg. This new species is assigned to a newly proposed species group, the Labidoceramadurae species group, within the Labidoceradetruncata species complex. In this species complex five Indo-West Pacific species groups are recognized (cervi, detruncata, gangetica, madurae, and pavo) and defined on the basis of difference in sexual dimorphism.

  11. A new species of Labidocera (Copepoda, Calanoida, Pontellidae collected from Okinawa, southwestern Japan, with establishment of five Indo-West Pacific species groups in the L. detruncata species complex

    Directory of Open Access Journals (Sweden)

    Takeshi Hirabayashi

    2014-10-01

    Full Text Available Labidocera churaumi sp. n. is described from Okinawa, southwestern Japan. The female of the new species differs from other congeners in genital compound somite with right postero-lateral and left antero-lateral processes. The male is distinguished from other congeners by the structure of the fifth leg. This new species is assigned to a newly proposed species group, the L. madurae species group, within the L. detruncata species complex. In this species complex five Indo-West Pacific species groups are recognized (cervi, detruncata, gangetica, madurae, and pavo and defined on the basis of difference in sexual dimorphism.

  12. A new species of Labidocera (Copepoda, Calanoida, Pontellidae) collected from Okinawa, southwestern Japan, with establishment of five Indo-West Pacific species groups in the L. detruncata species complex

    Science.gov (United States)

    Hirabayashi, Takeshi; Ohtsuka, Susumu

    2014-01-01

    Abstract Labidocera churaumi sp. n. is described from Okinawa, southwestern Japan. The female of the new species differs from other congeners in genital compound somite with right postero-lateral and left antero-lateral processes. The male is distinguished from other congeners by the structure of the fifth leg. This new species is assigned to a newly proposed species group, the Labidocera madurae species group, within the Labidocera detruncata species complex. In this species complex five Indo-West Pacific species groups are recognized (cervi, detruncata, gangetica, madurae, and pavo) and defined on the basis of difference in sexual dimorphism. PMID:25349514

  13. Genetic interactions underlying hybrid male sterility in the Drosophila bipectinata species complex.

    Science.gov (United States)

    Mishra, Paras Kumar; Singh, Bashisth Narayan

    2006-06-01

    Understanding genetic mechanisms underlying hybrid male sterility is one of the most challenging problems in evolutionary biology especially speciation. By using the interspecific hybridization method roles of Y chromosome, Major Hybrid Sterility (MHS) genes and cytoplasm in sterility of hybrid males have been investigated in a promising group, the Drosophila bipectinata species complex that consists of four closely related species: D. pseudoananassae, D. bipectinata, D. parabipectinata and D. malerkotliana. The interspecific introgression analyses show that neither cytoplasm nor MHS genes are involved but X-Y interactions may be playing major role in hybrid male sterility between D. pseudoananassae and the other three species. The results of interspecific introgression analyses also show considerable decrease in the number of males in the backcross offspring and all males have atrophied testes. There is a significant positive correlation between sex - ratio distortion and severity of sterility in backcross males. These findings provide evidence that D. pseudoananassae is remotely related with other three species of the D. bipectinata species complex.

  14. Hyphal growth of phagocytosed Fusarium oxysporum causes cell lysis and death of murine macrophages.

    Directory of Open Access Journals (Sweden)

    Katja Schäfer

    Full Text Available Fusarium oxysporum is an important plant pathogen and an opportunistic pathogen of humans. Here we investigated phagocytosis of F. oxysporum by J774.1 murine cell line macrophages using live cell video microscopy. Macrophages avidly migrated towards F. oxysporum germlings and were rapidly engulfed after cell-cell contact was established. F. oxysporum germlings continued hyphal growth after engulfment by macrophages, leading to associated macrophage lysis and escape. Macrophage killing depended on the multiplicity of infection. After engulfment, F. oxysporum inhibited macrophages from completing mitosis, resulting in large daughter cells fused together by means of a F. oxysporum hypha. These results shed new light on the initial stages of Fusarium infection and the innate immune response of the mammalian host.

  15. Hyphal growth of phagocytosed Fusarium oxysporum causes cell lysis and death of murine macrophages.

    Science.gov (United States)

    Schäfer, Katja; Bain, Judith M; Di Pietro, Antonio; Gow, Neil A R; Erwig, Lars P

    2014-01-01

    Fusarium oxysporum is an important plant pathogen and an opportunistic pathogen of humans. Here we investigated phagocytosis of F. oxysporum by J774.1 murine cell line macrophages using live cell video microscopy. Macrophages avidly migrated towards F. oxysporum germlings and were rapidly engulfed after cell-cell contact was established. F. oxysporum germlings continued hyphal growth after engulfment by macrophages, leading to associated macrophage lysis and escape. Macrophage killing depended on the multiplicity of infection. After engulfment, F. oxysporum inhibited macrophages from completing mitosis, resulting in large daughter cells fused together by means of a F. oxysporum hypha. These results shed new light on the initial stages of Fusarium infection and the innate immune response of the mammalian host.

  16. Lineage diversification and hybridization in the Cayratia japonica-Cayratia tenuifolia species complex.

    Science.gov (United States)

    Ishikawa, Naoko; Ikeda, Hajime; Yi, Ting-shuang; Takabe-Ito, Eriko; Okada, Hiroshi; Tsukaya, Hirokazu

    2014-06-01

    The Cayratia japonica-Cayratia tenuifolia species complex (Vitaceae) is distributed from temperate to tropical East Asia, Southeast Asia, India, and Australia. The spatiotemporal diversification history of this complex was assessed through phylogenetic and biogeographic analyses. Maximum parsimony, neighbor-joining, and maximum likelihood methods were used to analyze sequences of one nuclear (AS1) and two plastid regions (trnL-F and trnC-petN). Bayesian dating analysis was conducted to estimate the divergence times of clades. The likelihood method LAGRANGE was used to infer ancestral areas. The Asian C. japonica and C. tenuifolia should be treated as an unresolved complex, and Australian C. japonica is distinct from the Asian C. japonica-C. tenuifolia species complex and should be treated as separate taxa. The Asian C. japonica-C. tenuifolia species complex was estimated to have diverged from its closest relatives during the Late Eocene (35.1 million years ago [Ma], 95% highest posterior densities [HPD]=23.3-47.3Ma) and most likely first diverged in mid-continental Asia. This complex was first divided into a northern clade and a southern clade during the middle Oligocene (27.3Ma; 95% HPD=17.4-38.1Ma), which is consistent with a large southeastward extrusion of the Indochina region relative to South China along the Red River. Each of the northern and southern clades then further diverged into multiple subclades through a series of dispersal and divergence events following significant geological and climatic changes in East and Southeast Asia during the Miocene. Multiple inter-lineage hybridizations among four lineages were inferred to have occurred following this diversification process, which caused some Asian lineages to be morphologically cryptic. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. EVALUATING THE NOVEL METHODS ON SPECIES DISTRIBUTION MODELING IN COMPLEX FOREST

    Directory of Open Access Journals (Sweden)

    C. H. Tu

    2012-07-01

    Full Text Available The prediction of species distribution has become a focus in ecology. For predicting a result more effectively and accurately, some novel methods have been proposed recently, like support vector machine (SVM and maximum entropy (MAXENT. However, high complexity in the forest, like that in Taiwan, will make the modeling become even harder. In this study, we aim to explore which method is more applicable to species distribution modeling in the complex forest. Castanopsis carlesii (long-leaf chinkapin, LLC, growing widely in Taiwan, was chosen as the target species because its seeds are an important food source for animals. We overlaid the tree samples on the layers of altitude, slope, aspect, terrain position, and vegetation index derived from SOPT-5 images, and developed three models, MAXENT, SVM, and decision tree (DT, to predict the potential habitat of LLCs. We evaluated these models by two sets of independent samples in different site and the effect on the complexity of forest by changing the background sample size (BSZ. In the forest with low complex (small BSZ, the accuracies of SVM (kappa = 0.87 and DT (0.86 models were slightly higher than that of MAXENT (0.84. In the more complex situation (large BSZ, MAXENT kept high kappa value (0.85, whereas SVM (0.61 and DT (0.57 models dropped significantly due to limiting the habitat close to samples. Therefore, MAXENT model was more applicable to predict species’ potential habitat in the complex forest; whereas SVM and DT models would tend to underestimate the potential habitat of LLCs.

  18. Magnetic interactions as a stabilizing factor of semiquinone species of lawsone by metal complexation

    International Nuclear Information System (INIS)

    Valle-Bourrouet, Grettel; Ugalde-Saldivar, Victor M.; Gomez, Martin; Ortiz-Frade, Luis A.; Gonzalez, Ignacio; Frontana, Carlos

    2010-01-01

    Changes in electrochemical reactivity for lawsone anions (lawsone, 2-hydroxy-1,4-naphthoquinone, HLw) being coordinated to a series of metallic ions in dimethylsulfoxide solution were evaluated. Upon performing cyclic voltammetry experiments for metal complexes of this quinone with pyridine (Py) - structural formula M(II)(Lw - ) 2 (Py) 2 ; M: Co(II), Ni(II), Zn(II) - it was found that the reduction of coordinated Lw - units occurs during the first and second electron uptake in the analyzed compounds. The stability of the electrogenerated intermediates for each complex depends on the d electron configuration in each metal center and is determined by magnetic interactions with the available spins considering an octahedral conformation for all the compounds. This was evidenced by in situ spectroelectrochemical-ESR measurements in the Zn(II) complex in which due to the lack of magnetic interaction owing to its electron configuration, the structure of the coordinated anion radical species was determined. Successive reduction of the associated Lw - units leads to partial dissociation of the complex, determined by the identification of free radical dianion structures in solution. These results show some insights on how metal-lawsone complexation can modify the solution reactivity and stability of the electrogenerated radical species.

  19. Magnetic interactions as a stabilizing factor of semiquinone species of lawsone by metal complexation

    Energy Technology Data Exchange (ETDEWEB)

    Valle-Bourrouet, Grettel [Universidad de Costa Rica, Escuela de Quimica, San Jose (Costa Rica); Ugalde-Saldivar, Victor M. [Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, C.P. 04510, Mexico, D.F. (Mexico); Gomez, Martin [Departamento de Sistemas Biologicos, Universidad Autonoma Metropolitana-Xochimilco, C.P. 04960, Mexico, D.F. (Mexico); Ortiz-Frade, Luis A. [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica, Parque Tecnologico Queretaro, Sanfandila, 76703, Pedro Escobedo, Queretaro (Mexico); Gonzalez, Ignacio [Universidad Autonoma Metropolitana - Iztapalapa, Departamento de Quimica, Area de Electroquimica, Apartado postal 55-534, 09340, Mexico, D.F. (Mexico); Frontana, Carlos, E-mail: ultrabuho@yahoo.com.m [Departamento de Quimica, Centro de Investigacion y Estudios Avanzados, Av. Instituto Politecnico Nacional No. 2508 Col. San Pedro Zacatenco, C.P. 07360, Mexico, D.F. (Mexico)

    2010-12-01

    Changes in electrochemical reactivity for lawsone anions (lawsone, 2-hydroxy-1,4-naphthoquinone, HLw) being coordinated to a series of metallic ions in dimethylsulfoxide solution were evaluated. Upon performing cyclic voltammetry experiments for metal complexes of this quinone with pyridine (Py) - structural formula M(II)(Lw{sup -}){sub 2}(Py){sub 2}; M: Co(II), Ni(II), Zn(II) - it was found that the reduction of coordinated Lw{sup -} units occurs during the first and second electron uptake in the analyzed compounds. The stability of the electrogenerated intermediates for each complex depends on the d electron configuration in each metal center and is determined by magnetic interactions with the available spins considering an octahedral conformation for all the compounds. This was evidenced by in situ spectroelectrochemical-ESR measurements in the Zn(II) complex in which due to the lack of magnetic interaction owing to its electron configuration, the structure of the coordinated anion radical species was determined. Successive reduction of the associated Lw{sup -} units leads to partial dissociation of the complex, determined by the identification of free radical dianion structures in solution. These results show some insights on how metal-lawsone complexation can modify the solution reactivity and stability of the electrogenerated radical species.

  20. Solution XAS Analysis for Exploring the Active Species in Homogeneous Vanadium Complex Catalysis

    Science.gov (United States)

    Nomura, Kotohiro; Mitsudome, Takato; Tsutsumi, Ken; Yamazoe, Seiji

    2018-06-01

    Selected examples in V K-edge X-ray Absorption Near Edge Structure (XANES) analysis of a series of vanadium complexes containing imido ligands (possessing metal-nitrogen double bond) in toluene solution have been introduced, and their pre-edge and the edge were affected by their structures and nature of ligands. Selected results in exploring the oxidation states of the active species in ethylene dimerization/polymerization using homogeneous vanadium catalysts [consisting of (imido)vanadium(V) complexes and Al cocatalysts] by X-ray absorption spectroscopy (XAS) analyses have been introduced. It has been demonstrated that the method should provide more clear information concerning the active species in situ, especially by combination with the other methods (NMR and ESR spectra, X-ray crystallographic analysis, and reaction chemistry), and should be powerful tool for study of catalysis mechanism as well as for the structural analysis in solution.

  1. The Noah's Ark experiment: species dependent biodistributions of cationic 99mTc complexes

    International Nuclear Information System (INIS)

    Deutsch, Edward; Ketring, A.R.; Libson, Karen; Vanderheyden, J.-L.; Hirth, W.W.

    1989-01-01

    The time dependent biodistributions of three related 99m Tc complexes of 1, 2-bis(dimethylphosphino)ethane (DMPE) were evaluated in several animal species including humans: trans-[ 99m Tc v (DMPE) 2 O 2 ] + , trans-[ 99m Tc III (DMPE) 2 Cl 2 ] + and [ 99m Tc I (DMPE) 3 ] + . Imaging studies were performed in 10 animal species to evaluate these complexes as myocardial perfusion imaging agents. Animal models adequately predict the uninteresting behaviour of the Tc(V) cation in humans, predict to only a very limited extent the behaviour of the Tc(III) cation in humans and totally fail to predict the behaviour of the Tc(I) cation in humans. (U.K.)

  2. NADPH-dependent D-aldose reductases and xylose fermentation in Fusarium oxysporum

    DEFF Research Database (Denmark)

    Panagiotou, Gianni; Christakopoulos, P.

    2004-01-01

    for NADPH over NADH. In this study, the influence of aeration and the response to the addition of electron acceptors on xylose fermentation by F. oxysporum were also studied. The batch cultivation of F. oxysporum on xylose was performed under aerobic, anaerobic and oxygen-limited conditions in stirred tank...... conditions (0.3 vvm). When the artificial electron acceptor acetoin was added to an anaerobic batch fermentation of xylose by F. oxysporum, the ethanol yield increased while xylitol excretion was also decreased....

  3. Mekanisme Parasitisme Trichoderma Harzianum Terhadap Fusarium Oxysporum Pada Semai Acacia Mangium

    OpenAIRE

    Tasik, Susanti; Widyastuti, Siti Muslimah; Harjono

    2015-01-01

    Mechanism of parasitism of Trichoderma harzianum on Fusarium oxysporum on Acacia mangium seedlings. Fusarium oxysporum is one of the most important soil-borne fungi the causal agent of damping-off disease. Detailed information it needed to know how the pathogen can be inhibited by Trichoderma harzianum. The objective of this research was to investigate the inhibition mechanism of T. harzianum on F. oxysporum in vitro and in planta. Green Flourescent Protein (GFP) T. harzianum was used as bioc...

  4. Hybrid sterility in crosses between two Brazilian sibling species of the Anopheles albitarsis complex.

    Science.gov (United States)

    Fontoura, Nathalia Giglio; Araki, Alejandra Saori; Van Der Maas Azevedo, Renata; Galardo, Allan Kardec Ribeiro; Peixoto, Alexandre Afranio; Lima, José Bento Pereira

    2014-12-04

    Complexes of cryptic species are common in several taxa and this is also the case in the Anopheles genus, a group including all known human malaria vectors. The Anopheles albitarsis complex comprises at least nine cryptic species, some of which are implicated as vectors of human malaria. Several different types of data have been generated for this species complex such as cytogenetics, alloenzymes, morphological and feeding behavioral, hybridization experiments, RAPD-PCR and RFLP and mitochondrial and nuclear markers. Studies focused on its postzygotic isolation are still somewhat rare in the literature despite their importance to understand the speciation process and the level of gene flow potentially occurring among the different sibling species. Hybridization experiments between Anopheles albitarsis s.s. and Anopheles marajoara, as well as backcrosses between hybrids and Anopheles albitarsis s.s., were performed using the induced mating technique. Results were compared to intraspecific crosses. Larva-to-adult viability and sex ratio were also assessed. Male hybrids show very low insemination rates and nearly complete sterility, apparently due to abnormalities in their reproductive organs. Evidence of partial sterility among the hybrid females was also observed. Our data indicated that Anopheles albitarsis s.s. and Anopheles marajoara show a high level of postzygotic isolation with a strong hybrid male sterility. This result is consistent with the Haldane's rule which states that in interspecific crosses the heterogametic sex is the first to be affected. However, the fact that the females are not completely sterile raises the possibility of introgression between these two siblings species.

  5. Phenotypic differentiation in love song traits among sibling species of the Lutzomyia longipalpis complex in Brazil.

    Science.gov (United States)

    Vigoder, Felipe M; Souza, Nataly A; Brazil, Reginaldo P; Bruno, Rafaela V; Costa, Pietra L; Ritchie, Michael G; Klaczko, Louis B; Peixoto, Alexandre A

    2015-05-28

    Brazilian populations of Lutzomyia longipalpis may constitute a complex of cryptic species, and this report investigates the distribution and number of potential sibling species. One of the main differences observed among Brazilian populations is the type of acoustic signal produced by males during copulation. These copulation song differences seem to be evolving faster than neutral molecular markers and have been suggested to contribute to insemination failure observed in crosses between these sibling species. In previous studies, two main types of copulation songs were found, burst-type and pulse-type. The latter type can, in turn, be further subdivided into five different patterns. We recorded male song from 13 new populations of the L. longipalpis complex from Brazil and compared the songs with 12 already available. Out of these 25 populations, 16 produce burst-type and 9 produce pulse-type songs. We performed a principal component analysis in these two main groups separately and an additional discriminant analysis in the pulse-type group. The pulse-type populations showed a clear separation between the five known patterns with a high correspondence of individuals to their correct group, confirming the differentiation between them. The distinctiveness of the burst-type subgroups was much lower than that observed among the pulse-type groups and no clear population structure was observed. This suggests that the burst-type populations represent a single species. Overall, our results are consistent with the existence in Brazil of at least six species of the L. longipalpis complex, one with a wide distribution comprising all the populations with burst-type songs, and five more closely related allopatric siblings with different pulse-type song patterns and more restricted distribution ranges.

  6. Plastome Sequence Determination and Comparative Analysis for Members of the Lolium-Festuca Grass Species Complex

    OpenAIRE

    Hand, Melanie L.; Spangenberg, German C.; Forster, John W.; Cogan, Noel O. I.

    2013-01-01

    Chloroplast genome sequences are of broad significance in plant biology, due to frequent use in molecular phylogenetics, comparative genomics, population genetics, and genetic modification studies. The present study used a second-generation sequencing approach to determine and assemble the plastid genomes (plastomes) of four representatives from the agriculturally important Lolium-Festuca species complex of pasture grasses (Lolium multiflorum, Festuca pratensis, Festuca altissima, and Festuca...

  7. Insights on the identities of sharks of the Rhizoprionodon acutus (Elasmobranchii: Carcharhiniformes) species complex based on three new species of Phoreiobothrium (Cestoda: Onchoproteocephalidea).

    Science.gov (United States)

    Caira, J N; Jensen, K

    2015-12-22

    Recent molecular work on milk sharks (Rhizoprionodon acutus [Rüppell]) suggests that, rather than a single widely distributed species, R. acutus represents a complex of four narrowly distributed cryptic species. Examination of the cestodes in three of the four members of that complex globally led to the discovery and description of three new species in the onchoproteocephalidean genus Phoreiobothrium Linton, 1889. The host associations and geographic distributions of the new species are fully congruent with the geographic distributions and species boundaries inferred for the sharks from molecular data: Phoreiobothrium jahki n. sp. parasitizes Rhizoprionodon cf. acutus 3 off Borneo, P. nadiae n. sp. parasitizes R. cf. acutus 1 off Senegal, and P. swaki n. sp. parasitizes R. cf. acutus 2 off northern Australia. The new cestodes differ from one another and from their 11 valid congeners in morphological features such as sublocular configuration and number, hook size, and testis number. Given the notoriously oioxenous nature of elasmobranch-hosted onchoproteocephalidean cestodes, these results provide further support for recognition of the milk shark species complex. This work also raises questions about the Phoreiobothrium species reported in cursory descriptions from India; further examination of these cestodes is key because they are potentially hosted by the fourth member of the R. acutus complex. To encourage future taxonomic work on the morphology of sharks in this complex, comparative photographs of representatives of the four potential host species are provided.

  8. Identification and characterization of a highly variable region in mitochondrial genomes of fusarium species and analysis of power generation from microbial fuel cells

    Science.gov (United States)

    Hamzah, Haider Mousa

    In the microbial fuel cell (MFC) project, power generation from Shewanella oneidensis MR-1 was analyzed looking for a novel system for both energy generation and sustainability. The results suggest the possibility of generating electricity from different organic substances, which include agricultural and industrial by-products. Shewanella oneidensis MR-1 generates usable electrons at 30°C using both submerged and solid state cultures. In the MFC biocathode experiment, most of the CO2 generated at the anodic chamber was converted into bicarbonate due the activity of carbonic anhydrase (CA) of the Gluconobacter sp.33 strain. These findings demonstrate the possibility of generation of electricity while at the same time allowing the biomimetic sequestration of CO2 using bacterial CA. In the mitochondrial genomes project, the filamentous fungal species Fusarium oxysporum was used as a model. This species causes wilt of several important agricultural crops. A previous study revealed that a highly variable region (HVR) in the mitochondrial DNA (mtDNA) of three species of Fusarium contained a large, variable unidentified open reading frame (LV-uORF). Using specific primers for two regions of the LV-uORF, six strains were found to contain the ORF by PCR and database searches identified 18 other strains outside of the Fusarium oxysporum species complex. The LV-uORF was also identified in three isolates of the F. oxysporum species complex. Interestingly, several F. oxysporum isolates lack the LV-uORF and instead contain 13 ORFs in the HVR, nine of which are unidentified. The high GC content and codon usage of the LV-uORF indicate that it did not co-evolve with other mt genes and was horizontally acquired and was introduced to the Fusarium lineage prior to speciation. The nonsynonymous/synonymous (dN/dS) ratio of the LV-uORFs (0.43) suggests it is under purifying selection and the putative polypeptide is predicted to be located in the mitochondrial membrane. Growth assays

  9. Molecular data reveal complex hybridization and a cryptic species of neotropical wild cat.

    Science.gov (United States)

    Trigo, Tatiane C; Schneider, Alexsandra; de Oliveira, Tadeu G; Lehugeur, Livia M; Silveira, Leandro; Freitas, Thales R O; Eizirik, Eduardo

    2013-12-16

    Hybridization among animal species has recently become more recognized as an important phenomenon, especially in the context of recent radiations. Here we show that complex hybridization has led to contrasting patterns of genomic composition among closely related species of the Neotropical cat genus Leopardus. We show strong evidence of ancient hybridization and introgression between the pampas cat (L. colocolo) and northeastern populations of tigrina (L. tigrinus), leading to remarkable cytonuclear discordance in the latter. In contrast, southern tigrina populations show recent and continuing hybridization with Geoffroy's cat (L. geoffroyi), leading to extreme levels of interspecific admixture at their contact zone. Finally, we demonstrate that two seemingly continuous Brazilian tigrina populations show no evidence of ongoing gene flow between them, leading us to support their formal recognition as distinct species, namely L. tigrinus in the northeast and L. guttulus in the south. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Implementing the European policies for alien species – networking, science, and partnership in a complex environment

    Directory of Open Access Journals (Sweden)

    Stelios Katsanevakis

    2013-02-01

    Full Text Available The European Commission has recognized the need for more stringent action to manage biological invasions and has committed to develop adedicated legislative instrument. Under this upcoming legislation, European countries and their relevant institutions will have additional obligations and commitments in respect to invasive alien species. In September 2012, the European Commission’s Joint Research Centre (JRC launched the European Alien Species Information Network (EASIN to facilitate the exploration of existing alien species information from distributed sources and to assist the implementation of European policies on biological invasions. Subsequent to the launching of EASIN, there was an evident need to define its niche within a complex environment of global, European, regional and national information systems. Herein we propose an organizational chart clearly defining the role of each actor in this framework, and we emphasize the need for collaboration in order to effectively support EU policies.

  11. Ecological and epidemiological status of species of the Phlebotomus perniciosus complex (Diptera: Psychodidae, Phlebotominae) in Morocco.

    Science.gov (United States)

    Zarrouk, Asmae; Kahime, Kholoud; Boussaa, Samia; Belqat, Boutaïna

    2016-03-01

    Leishmania infantum (Kinetoplastida: Trypanosomatidae) infection is transmitted by an infected female sand fly (Diptera: Psychodidae, Phlebotominae) of the subgenus Larroussius: Phlebotomus ariasi, Phlebotomus perniciosus, and Phlebotomus longicuspis in the Mediterranean basin. In Morocco, the vectorial role of P. ariasi was demonstrated, while that of P. longicuspis and P. perniciosus is not elucidated. In addition, Moroccan P. longicuspis and P. perniciosus populations present a higher morphologic and genetic variability. It was classified as P. perniciosus complex, including typical (PN) and atypical (PNA) morphs of P. perniciosus, P. longicuspis sensu stricto (LCss), and a sibling species of P. longicuspis (LCx). With the aim to study the ecological and epidemiological status of P. perniciosus complex species in Morocco, entomological surveys were carried out during three entomological seasons (2012, 2013, and 2014). We collected a total of 6298 specimens from 81 localities of northern, central, and southern Morocco. After describing the geographical distribution of P. perniciosus complex trough Morocco according to many variables (altitude, latitude, and longitude), we discuss the resulting epidemiological implications of its species. Our results highlight the geographical distribution of the two morphs of P. perniciosus through Morocco: PN is limited to the north, while PNA is widespread in northern, central, and southern Morocco. In terms of vectorial role, we hypothesize the potential involvement of PN, LCss, and LCx, at least, with P. ariasi, in the epidemiological cycle of L. infantum in Morocco.

  12. Using Google Earth Surface Metrics to Predict Plant Species Richness in a Complex Landscape

    Directory of Open Access Journals (Sweden)

    Sebastián Block

    2016-10-01

    Full Text Available Google Earth provides a freely available, global mosaic of high-resolution imagery from different sensors that has become popular in environmental and ecological studies. However, such imagery lacks the near-infrared band often used in studying vegetation, thus its potential for estimating vegetation properties remains unclear. In this study, we assess the potential of Google Earth imagery to describe and predict vegetation attributes. Further, we compare it to the potential of SPOT imagery, which has additional spectral information. We measured basal area, vegetation height, crown cover, density of individuals, and species richness in 60 plots in the oak forests of a complex volcanic landscape in central Mexico. We modelled each vegetation attribute as a function of surface metrics derived from Google Earth and SPOT images, and selected the best-supported linear models from each source. Total species richness was the best-described and predicted variable: the best Google Earth-based model explained nearly as much variation in species richness as its SPOT counterpart (R2 = 0.44 and 0.51, respectively. However, Google Earth metrics emerged as poor predictors of all remaining vegetation attributes, whilst SPOT metrics showed potential for predicting vegetation height. We conclude that Google Earth imagery can be used to estimate species richness in complex landscapes. As it is freely available, Google Earth can broaden the use of remote sensing by researchers and managers in low-income tropical countries where most biodiversity hotspots are found.

  13. Molecular phylogeny of Glossodoris (Ehrenberg, 1831) nudibranchs and related genera reveals cryptic and pseudocryptic species complexes

    KAUST Repository

    Matsuda, Shayle B.; Gosliner, Terrence M.

    2017-01-01

    Chromodorid nudibranchs (Chromodorididae) are brightly coloured sea slugs that live in some of the most biodiverse and threatened coral reefs on the planet. However, the evolutionary relationships within this family have not been well understood, especially in the genus Glossodoris. Members of Glossodoris have experienced large-scale taxonomic instability over the last century and have been the subject of repeated taxonomic changes, in part due to morphological characters being the sole traditional taxonomic sources of data. Changing concepts of traditional generic boundaries based on morphology also have contributed to this instability. Despite recent advances in molecular systematics, many aspects of chromodorid taxonomy remain poorly understood, particularly at the traditional species and generic levels. In this study, 77 individuals comprising 32 previously defined species were used to build the most robust phylogenetic tree of Glossodoris and related genera using mitochondrial genes cytochrome c oxidase subunit I and 16S, and the nuclear gene 28S. Bayesian inference, maximum likelihood, and maximum parsimony analyses verify the most recent hypothesized evolutionary relationships within Glossodoris. Additionally, a pseudocryptic and cryptic species complex within Glossodoris cincta and a pseudocryptic complex within Glossodoris pallida emerged, and three new species of Doriprismatica are identified.

  14. Molecular phylogeny of Glossodoris (Ehrenberg, 1831) nudibranchs and related genera reveals cryptic and pseudocryptic species complexes

    KAUST Repository

    Matsuda, Shayle B.

    2017-03-01

    Chromodorid nudibranchs (Chromodorididae) are brightly coloured sea slugs that live in some of the most biodiverse and threatened coral reefs on the planet. However, the evolutionary relationships within this family have not been well understood, especially in the genus Glossodoris. Members of Glossodoris have experienced large-scale taxonomic instability over the last century and have been the subject of repeated taxonomic changes, in part due to morphological characters being the sole traditional taxonomic sources of data. Changing concepts of traditional generic boundaries based on morphology also have contributed to this instability. Despite recent advances in molecular systematics, many aspects of chromodorid taxonomy remain poorly understood, particularly at the traditional species and generic levels. In this study, 77 individuals comprising 32 previously defined species were used to build the most robust phylogenetic tree of Glossodoris and related genera using mitochondrial genes cytochrome c oxidase subunit I and 16S, and the nuclear gene 28S. Bayesian inference, maximum likelihood, and maximum parsimony analyses verify the most recent hypothesized evolutionary relationships within Glossodoris. Additionally, a pseudocryptic and cryptic species complex within Glossodoris cincta and a pseudocryptic complex within Glossodoris pallida emerged, and three new species of Doriprismatica are identified.

  15. Genetic relatedness of Trichoderma isolates antagonistic against Fusarium oxysporum f.sp. dianthi inflicting carnation wilt.

    Science.gov (United States)

    Shanmugam, V; Sharma, Vivek; Ananthapadmanaban

    2008-01-01

    Twenty-eight isolates of Trichoderma belonging to four different species were screened in vitro for their antagonistic ability against Fusarium oxysporum f.sp. dianthi causing carnation wilt. Three different levels of antagonism observed in dual plate assay were further confirmed by cell-free culture filtrate experiments. Isolates showing class I level of antagonism produced maximum lytic enzymes, chitinases and beta-1,3-glucanases. Genetic variability of 25 selected isolates was assessed by random amplified polymorphic DNA technique and the amplified products were correlated for their level of antagonism. Unweighed pair-group method with arithmetical averages cluster analysis revealed prominent inter-and intraspecific genetic variation among the isolates. Based on their genetic relationship, the isolates were mainly distributed into 3 major groups representing T. atroviride, T. pseudokoningii and T. harzianum, with 20-35% interspecific dissimilarity. However, the polymorphism shown by the isolates did not correlate to their level of antagonism.

  16. Development of 16 Microsatellite Markers within the Camassia (Agavaceae Species Complex and Amplification in Related Taxa

    Directory of Open Access Journals (Sweden)

    Theresa M. Culley

    2013-07-01

    Full Text Available Premise of the study: The North American genus Camassia is an ecologically important group whose variability and evolution are little understood, being influenced by hybridization and geographic isolation. We developed microsatellite markers to investigate patterns of gene flow, population structure, and taxonomic relationships within this group. Methods and Results: Using a traditional approach with biotin-labeled probes, we developed 16 microsatellite primers in three species of Camassia: C. howellii, C. leichtlinii, and C. quamash. The number of alleles per locus averaged 3.94 per species, and levels of heterozygosity ranged from 0.000 to 1.00 and 0.033 to 0.917 for observed and expected heterozygosities, respectively. All primers amplified to varying extents in additional species (C. angusta, C. cusickii, C. scilloides and in putative species in a related genus (Hastingsia alba, H. atropurpurea, H. bracteosa, H. serpentinicola. Conclusions: These microsatellite markers exhibit variation and are useful for ongoing studies of integrative taxonomy and population differentiation within this species complex.

  17. Sequencing of individual chromosomes of plant pathogenic Fusarium oxysporum.

    Science.gov (United States)

    Kashiwa, Takeshi; Kozaki, Toshinori; Ishii, Kazuo; Turgeon, B Gillian; Teraoka, Tohru; Komatsu, Ken; Arie, Tsutomu

    2017-01-01

    A small chromosome in reference isolate 4287 of F. oxysporum f. sp. lycopersici (Fol) has been designated as a 'pathogenicity chromosome' because it carries several pathogenicity related genes such as the Secreted In Xylem (SIX) genes. Sequence assembly of small chromosomes in other isolates, based on a reference genome template, is difficult because of karyotype variation among isolates and a high number of sequences associated with transposable elements. These factors often result in misassembly of sequences, making it unclear whether other isolates possess the same pathogenicity chromosome harboring SIX genes as in the reference isolate. To overcome this difficulty, single chromosome sequencing after Contour-clamped Homogeneous Electric Field (CHEF) separation of chromosomes was performed, followed by de novo assembly of sequences. The assembled sequences of individual chromosomes were consistent with results of probing gels of CHEF separated chromosomes with SIX genes. Individual chromosome sequencing revealed that several SIX genes are located on a single small chromosome in two pathogenic forms of F. oxysporum, beyond the reference isolate 4287, and in the cabbage yellows fungus F. oxysporum f. sp. conglutinans. The particular combination of SIX genes on each small chromosome varied. Moreover, not all SIX genes were found on small chromosomes; depending on the isolate, some were on big chromosomes. This suggests that recombination of chromosomes and/or translocation of SIX genes may occur frequently. Our method improves sequence comparison of small chromosomes among isolates. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Complexation of sodium caseinate with gum tragacanth: Effect of various species and rheology of coacervates.

    Science.gov (United States)

    Ghorbani Gorji, Sara; Ghorbani Gorji, Elham; Mohammadifar, Mohammad Amin; Zargaraan, Azizollaah

    2014-06-01

    We investigated complex coacervation of sodium caseinate/Astragalus rahensis (A.r) as a function of pH with light scattering, spectrophotometry, and viscosity measurements. Interestingly, sodium caseinate/A.r displayed five structural transitions; pH 7.00 to pH ∼5.40: no interaction occurred, pH ∼5.40 to pH ∼4.80: initiation of the formation of primary soluble complexes, pH ∼4.80 to ∼4.30: formation of interpolymer complexes, pH ∼4.30 to ∼4.02: optimum coacervation and pH ∼4.02 to ∼2.50: suppression of coacervation. In addition, rheological properties of sodium caseinate/A.r coacervates were studied at various pH values. A much higher storage modulus (G') than loss modulus (G″) for all sodium caseinate/A.r coacervates suggests the formation of highly interconnected gel-like network structures with mainly elastic behaviour. Moreover, sodium caseinate/A.r coacervates at all pH values exhibited a shear thinning behaviour across the entire shear rate range investigated. Effects of different species of gum tragacanth on the interactions with sodium caseinate have been scarcely studied. Our study showed that systems containing various species (A.r, soluble fraction of A.r and Astragalus gossypinus (A.g)) had different critical pH values and particle sizes during complex coacervation, which could be due to different ratio of soluble to insoluble fractions and uronic acid content of various species. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Species delimitation of the Hyphydrus ovatus complex in western Palaearctic with an update of species distributions (Coleoptera, Dytiscidae

    Directory of Open Access Journals (Sweden)

    Johannes Bergsten

    2017-06-01

    Full Text Available The species status of Hyphydrus anatolicus Guignot, 1957 and H. sanctus Sharp, 1882, previously often confused with the widespread H. ovatus (Linnaeus, 1760, are tested with molecular and morphological characters. Cytochrome c oxidase subunit 1 (CO1 was sequenced for 32 specimens of all three species. Gene-trees were inferred with parsimony, time-free bayesian and strict clock bayesian analyses. The GMYC model was used to estimate species limits. All three species were reciprocally monophyletic with CO1 and highly supported. The GMYC species delimitation analysis unequivocally delimited the three species with no other than the three species solution included in the confidence interval. A likelihood ratio test rejected the one-species null model. Important morphological characters distinguishing the species are provided and illustrated. New distributional data are given for the following species: Hyphydrus anatolicus from Slovakia and Ukraine, and H. aubei Ganglbauer, 1891, and H. sanctus from Turkey.

  20. Diversity and Distribution of Cryptic Species of the Bemisia tabaci (Hemiptera: Aleyrodidae) complex in Pakistan.

    Science.gov (United States)

    Masood, Mariyam; Amin, Imran; Hassan, Ishtiaq; Mansoor, Shahid; Brown, Judith K; Briddon, Rob W

    2017-12-05

    Bemisia tabaci (Gennadius; Hempitera: Aleyrodidae) is considered to be a cryptic (sibling) species complex, the members of which exhibit morphological invariability while being genetically and behaviorally distinct. Members of the complex are agricultural pests that cause direct damage by feeding on plants, and indirectly by transmitting viruses that cause diseases leading to reduced crop yield and quality. In Pakistan, cotton leaf curl disease, caused by multiple begomovirus species, is the most economically important viral disease of cotton. In the study outlined here, the diversity and geographic distribution of B. tabaci cryptic species was investigated by analyzing a taxonomically informative fragment of the mitochondrial cytochrome c oxidase 1 gene (mtCOI-3'). The mtCOI-3' sequence was determined for 285 adult whiteflies and found to represent six cryptic species, the most numerous being Asia II-1 and Middle East Asia Minor 1 (MEAM-1), the later also referred to as the B-biotype, which was previously thought to be confined to Sindh province but herein, was also found to be present in the Punjab province. The endemic Asia I was restricted to Sindh province, while an individual in the Asia II-8 was identified in Pakistan for the first time. Also for the first time, samples were collected from northwestern Pakistan and Asia II-1 was identified. Results indicate that in Pakistan the overall diversity of B. tabaci cryptic species is high and, based on comparisons with findings from previous studies, the distribution is dynamic. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. MEDIATOR18 and MEDIATOR20 confer susceptibility to Fusarium oxysporum in Arabidopsis thaliana

    Science.gov (United States)

    Stiller, Jiri; Davoine, Celine; Björklund, Stefan; Manners, John M.; Kazan, Kemal; Schenk, Peer M.

    2017-01-01

    The conserved protein complex known as Mediator conveys transcriptional signals by acting as an intermediary between transcription factors and RNA polymerase II. As a result, Mediator subunits play multiple roles in regulating developmental as well as abiotic and biotic stress pathways. In this report we identify the head domain subunits MEDIATOR18 and MEDIATOR20 as important susceptibility factors for Fusarium oxysporum infection in Arabidopsis thaliana. Mutants of MED18 and MED20 display down-regulation of genes associated with jasmonate signaling and biosynthesis while up-regulation of salicylic acid associated pathogenesis related genes and reactive oxygen producing and scavenging genes. We propose that MED18 and MED20 form a sub-domain within Mediator that controls the balance of salicylic acid and jasmonate associated defense pathways. PMID:28441405

  2. Complex species status for extinct moa (Aves: Dinornithiformes from the genus Euryapteryx.

    Directory of Open Access Journals (Sweden)

    Leon Huynen

    Full Text Available The exact species status of New Zealand's extinct moa remains unknown. In particular, moa belonging to the genus Euryapteryx have been difficult to classify. We use the DNA barcoding sequence on a range of Euryapteryx samples in an attempt to resolve the species status for this genus. We obtained mitochondrial control region and the barcoding region from Cytochrome Oxidase Subunit I (COI from a number of new moa samples and use available sequences from previous moa phylogenies and eggshell data to try and clarify the species status of Euryapteryx. Using the COI barcoding region we show that species status in Euryapteryx is complex with no clear separation between various individuals. Eggshell, soil, and bone data suggests that a Euryapteryx subspecies likely exists on New Zealand's North Island and can be characterized by a single mitochondrial control region SNP. COI divergences between Euryapteryx individuals from the south of New Zealand's South Island and those from the Far North of the North Island exceed 1.6% and are likely to represent separate species. Individuals from other areas of New Zealand were unable to be clearly separated based on COI differences possibly as a result of repeated hybridisation events. Despite the accuracy of the COI barcoding region to determine species status in birds, including that for the other moa genera, for moa from the genus Euryapteryx, COI barcoding fails to provide a clear result, possibly as a consequence of repeated hybridisation events between these moa. A single control region SNP was identified however that segregates with the two general morphological variants determined for Euryapteryx; a smaller subspecies restricted to the North Island of New Zealand, and a larger subspecies, found on both New Zealand's North and South Island.

  3. Complex species status for extinct moa (Aves: Dinornithiformes) from the genus Euryapteryx.

    Science.gov (United States)

    Huynen, Leon; Lambert, David M

    2014-01-01

    The exact species status of New Zealand's extinct moa remains unknown. In particular, moa belonging to the genus Euryapteryx have been difficult to classify. We use the DNA barcoding sequence on a range of Euryapteryx samples in an attempt to resolve the species status for this genus. We obtained mitochondrial control region and the barcoding region from Cytochrome Oxidase Subunit I (COI) from a number of new moa samples and use available sequences from previous moa phylogenies and eggshell data to try and clarify the species status of Euryapteryx. Using the COI barcoding region we show that species status in Euryapteryx is complex with no clear separation between various individuals. Eggshell, soil, and bone data suggests that a Euryapteryx subspecies likely exists on New Zealand's North Island and can be characterized by a single mitochondrial control region SNP. COI divergences between Euryapteryx individuals from the south of New Zealand's South Island and those from the Far North of the North Island exceed 1.6% and are likely to represent separate species. Individuals from other areas of New Zealand were unable to be clearly separated based on COI differences possibly as a result of repeated hybridisation events. Despite the accuracy of the COI barcoding region to determine species status in birds, including that for the other moa genera, for moa from the genus Euryapteryx, COI barcoding fails to provide a clear result, possibly as a consequence of repeated hybridisation events between these moa. A single control region SNP was identified however that segregates with the two general morphological variants determined for Euryapteryx; a smaller subspecies restricted to the North Island of New Zealand, and a larger subspecies, found on both New Zealand's North and South Island.

  4. Biology, ecology and control of the Penthaleus species complex (Acari: Penthaleidae).

    Science.gov (United States)

    Umina, Paul A; Hoffmann, Ary A; Weeks, Andrew R

    2004-01-01

    Blue oat mites, Penthaleus spp. (Acari: Penthaleidae), are major agricultural pests in southern Australia and other parts of the world, attacking various pasture, vegetable and crop plants. Management of these mites has been complicated by the recent discovery of three cryptic pest species of Penthaleus, whereas prior research had assumed a single species. The taxonomy, population genetics, ecology, biology and control of the Penthaleus spp. complex are reviewed. Adult Penthaleus have a dark blue-black body approximately 1 mm in length, and eight red-orange legs. Within Australia, they are winter pests completing two or three generations a season, depending on conditions. The summer is passed as diapausing eggs, when long-distance dispersal is thought to occur. The Penthaleus spp. reproduce by thelytokous parthenogenesis, with populations comprising clones that differ ecologically. The three pest Penthaleus spp. differ markedly in their distributions, plant hosts, timing of diapause egg production and response to pesticides, highlighting the need to develop control strategies that consider each species separately. Chemicals are the main weapons used in current control programs, however research continues into alternative more sustainable management options. Host plant resistance, crop rotations, conservation of natural enemies, and improved timing of pesticide application would improve the management of these pests. The most cost-effective and environmentally acceptable means of control will result from the integration of these practices combined with the development of a simple field-based kit to distinguish the different mite species.

  5. The distribution and host range of the banana Fusarium wilt fungus, Fusarium oxysporum f. sp. cubense, in Asia.

    Directory of Open Access Journals (Sweden)

    Diane Mostert

    Full Text Available Fusarium oxysporum formae specialis cubense (Foc is a soil-borne fungus that causes Fusarium wilt, which is considered to be the most destructive disease of bananas. The fungus is believed to have evolved with its host in the Indo-Malayan region, and from there it was spread to other banana-growing areas with infected planting material. The diversity and distribution of Foc in Asia was investigated. A total of 594 F. oxysporum isolates collected in ten Asian countries were identified by vegetative compatibility groups (VCGs analysis. To simplify the identification process, the isolates were first divided into DNA lineages using PCR-RFLP analysis. Six lineages and 14 VCGs, representing three Foc races, were identified in this study. The VCG complex 0124/5 was most common in the Indian subcontinent, Vietnam and Cambodia; whereas the VCG complex 01213/16 dominated in the rest of Asia. Sixty-nine F. oxysporum isolates in this study did not match any of the known VCG tester strains. In this study, Foc VCG diversity in Bangladesh, Cambodia and Sri Lanka was determined for the first time and VCGs 01221 and 01222 were first reported from Cambodia and Vietnam. New associations of Foc VCGs and banana cultivars were recorded in all the countries where the fungus was collected. Information obtained in this study could help Asian countries to develop and implement regulatory measures to prevent the incursion of Foc into areas where it does not yet occur. It could also facilitate the deployment of disease resistant banana varieties in infested areas.

  6. The distribution and host range of the banana Fusarium wilt fungus, Fusarium oxysporum f. sp. cubense, in Asia.

    Science.gov (United States)

    Mostert, Diane; Molina, Agustin B; Daniells, Jeff; Fourie, Gerda; Hermanto, Catur; Chao, Chih-Ping; Fabregar, Emily; Sinohin, Vida G; Masdek, Nik; Thangavelu, Raman; Li, Chunyu; Yi, Ganyun; Mostert, Lizel; Viljoen, Altus

    2017-01-01

    Fusarium oxysporum formae specialis cubense (Foc) is a soil-borne fungus that causes Fusarium wilt, which is considered to be the most destructive disease of bananas. The fungus is believed to have evolved with its host in the Indo-Malayan region, and from there it was spread to other banana-growing areas with infected planting material. The diversity and distribution of Foc in Asia was investigated. A total of 594 F. oxysporum isolates collected in ten Asian countries were identified by vegetative compatibility groups (VCGs) analysis. To simplify the identification process, the isolates were first divided into DNA lineages using PCR-RFLP analysis. Six lineages and 14 VCGs, representing three Foc races, were identified in this study. The VCG complex 0124/5 was most common in the Indian subcontinent, Vietnam and Cambodia; whereas the VCG complex 01213/16 dominated in the rest of Asia. Sixty-nine F. oxysporum isolates in this study did not match any of the known VCG tester strains. In this study, Foc VCG diversity in Bangladesh, Cambodia and Sri Lanka was determined for the first time and VCGs 01221 and 01222 were first reported from Cambodia and Vietnam. New associations of Foc VCGs and banana cultivars were recorded in all the countries where the fungus was collected. Information obtained in this study could help Asian countries to develop and implement regulatory measures to prevent the incursion of Foc into areas where it does not yet occur. It could also facilitate the deployment of disease resistant banana varieties in infested areas.

  7. The distribution and host range of the banana Fusarium wilt fungus, Fusarium oxysporum f. sp. cubense, in Asia

    Science.gov (United States)

    Molina, Agustin B.; Daniells, Jeff; Fourie, Gerda; Hermanto, Catur; Chao, Chih-Ping; Fabregar, Emily; Sinohin, Vida G.; Masdek, Nik; Thangavelu, Raman; Li, Chunyu; Yi, Ganyun; Mostert, Lizel; Viljoen, Altus

    2017-01-01

    Fusarium oxysporum formae specialis cubense (Foc) is a soil-borne fungus that causes Fusarium wilt, which is considered to be the most destructive disease of bananas. The fungus is believed to have evolved with its host in the Indo-Malayan region, and from there it was spread to other banana-growing areas with infected planting material. The diversity and distribution of Foc in Asia was investigated. A total of 594 F. oxysporum isolates collected in ten Asian countries were identified by vegetative compatibility groups (VCGs) analysis. To simplify the identification process, the isolates were first divided into DNA lineages using PCR-RFLP analysis. Six lineages and 14 VCGs, representing three Foc races, were identified in this study. The VCG complex 0124/5 was most common in the Indian subcontinent, Vietnam and Cambodia; whereas the VCG complex 01213/16 dominated in the rest of Asia. Sixty-nine F. oxysporum isolates in this study did not match any of the known VCG tester strains. In this study, Foc VCG diversity in Bangladesh, Cambodia and Sri Lanka was determined for the first time and VCGs 01221 and 01222 were first reported from Cambodia and Vietnam. New associations of Foc VCGs and banana cultivars were recorded in all the countries where the fungus was collected. Information obtained in this study could help Asian countries to develop and implement regulatory measures to prevent the incursion of Foc into areas where it does not yet occur. It could also facilitate the deployment of disease resistant banana varieties in infested areas. PMID:28719631

  8. Status of chemical elements in Atlantic Forest tree species near an industrial complex

    International Nuclear Information System (INIS)

    Araujo, A.L.L.; Fernandes, E.A.N.; Franca, E.J.; Bacchi, M.A.

    2008-01-01

    Environmental quality assessment studies have been conducted with tree species largely distributed in the Atlantic Forest. Leaf and soil samples were collected in the conservation unit Parque Estadual da Serra do Mar (PESM) nearby the industrial complex of Cubatao, Sao Paulo State, Brazil, and analyzed for chemical elements by instrumental neutron activation analysis. Results were compared to background values obtained in the Parque Estadual Carlos Botelho (PECB). The higher As, Fe, Hg and Zn mass fractions in the tree leaves of PESM indicated anthropogenic influence on this conservation unit. (author)

  9. Taxonomic status of the Bemisia tabaci complex (Hemiptera: Aleyrodidae and reassessment of the number of its constituent species.

    Directory of Open Access Journals (Sweden)

    Wonhoon Lee

    Full Text Available Bemisia tabaci (Hemiptera: Aleyrodidae is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species composing the B. tabaci complex were determined based on 1059 COI sequences of B. tabaci and 509 COI sequences of 153 hemipteran species. The genetic divergence within B. tabaci was conspicuously higher (on average, 11.1% than interspecific genetic divergence within the respective genera of the 153 species (on average, 6.5%. This result indicates that B. tabaci is composed of multiple species that may belong to different genera or subfamilies. A phylogenetic tree constructed based on 212 COI sequences without duplications revealed that the B. tabaci complex is composed of a total of 31 putative species, including a new species, JpL. However, genetic divergence within six species (Asia II 1, Asia II 7, Australia, Mediterranean, New World, and Sub Saharan Africa 1 was higher than 3.5%, which has been used as a threshold of species boundaries within the B. tabaci complex. These results suggest that it is necessary to increase the threshold for species boundaries up to 4% to distinguish the constituent species in the B. tabaci complex.

  10. Enhanced reactive oxygen species through direct copper sulfide nanoparticle-doxorubicin complexation

    Science.gov (United States)

    Li, Yajuan; Cupo, Michela; Guo, Liangran; Scott, Julie; Chen, Yi-Tzai; Yan, Bingfang; Lu, Wei

    2017-12-01

    CuS-based nanostructures loading the chemotherapeutic agent doxorubicin (DOX) exerted excellent cancer photothermal chemotherapy under multi-external stimuli. The DOX loading was generally designed through electrostatic interaction or chemical linkers. However, the interaction between DOX molecules and CuS nanoparticles has not been investigated. In this work, we use PEGylated hollow copper sulfide nanoparticles (HCuSNPs) to directly load DOX through the DOX/Cu2+ chelation process. Distinctively, the synthesized PEG-HCuSNPs-DOX release the DOX/Cu2+ complexes into surrounding environment, which generate significant reactive oxygen species (ROS) in a controlled manner by near-infrared laser. The CuS nanoparticle-mediated photothermal ablation facilitates the ROS-induced cancer cell killing effect. Our current work reveals a DOX/Cu2+-mediated ROS-enhanced cell-killing effect in addition to conventional photothermal chemotherapy through the direct CuS nanoparticle-DOX complexation.

  11. Induction, purification, and characterization of two extracellular alpha-L-arabinofuranosidases from Fusarium oxysporum

    DEFF Research Database (Denmark)

    Panagiotou, Gianni; Topakas, E.; Economou, L.

    2003-01-01

    In the presence of L-arabinose as sole carbon source, Fusarium oxysporum produces two alpha-L-arabinofuranosidases (ABFs) named ABF1 and ABF2, with molecular masses of 200 and 180 kDa, respectively. The two F. oxysporum proteins have been purified to homogeneity. The purified enzymes are composed...

  12. Genetic diversity in Fusarium oxysporum f.sp. dianthi and F. redolens f.sp. dianthi

    NARCIS (Netherlands)

    Baayen, R.P.; Dreven, van F.; Krijger, M.C.; Waalwijk, C.

    1997-01-01

    Pathogenic isolates were selected representing all known vegetative compatibility groups (VCGs) and races of Fusarium oxysporum sensu lato from Dianthus spp. On basis of differences in the internal transcribed spacer region of the ribosomal DNA, six VCGs were classified as F. oxysporum f.sp. dianthi

  13. Postantifungal Effect of Micafungin against the Species Complexes of Candida albicans and Candida parapsilosis.

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    Sandra Gil-Alonso

    Full Text Available Micafungin is an effective antifungal agent useful for the therapy of invasive candidiasis. Candida albicans is the most common cause of invasive candidiasis; however, infections due to non-C. albicans species, such as Candida parapsilosis, are rising. Killing and postantifungal effects (PAFE are important factors in both dose interval choice and infection outcome. The aim of this study was to determinate the micafungin PAFE against 7 C. albicans strains, 5 Candida dubliniensis, 2 Candida Africana, 3 C. parapsilosis, 2 Candida metapsilosis and 2 Candida orthopsilosis. For PAFE studies, cells were exposed to micafungin for 1 h at concentrations ranging from 0.12 to 8 μg/ml. Time-kill experiments (TK were conducted at the same concentrations. Samples were removed at each time point (0-48 h and viable counts determined. Micafungin (2 μg/ml was fungicidal (≥ 3 log10 reduction in TK against 5 out of 14 (36% strains of C. albicans complex. In PAFE experiments, fungicidal endpoint was achieved against 2 out of 14 strains (14%. In TK against C. parapsilosis, 8 μg/ml of micafungin turned out to be fungicidal against 4 out 7 (57% strains. Conversely, fungicidal endpoint was not achieved in PAFE studies. PAFE results for C. albicans complex (41.83 ± 2.18 h differed from C. parapsilosis complex (8.07 ± 4.2 h at the highest tested concentration of micafungin. In conclusion, micafungin showed significant differences in PAFE against C. albicans and C. parapsilosis complexes, being PAFE for the C. albicans complex longer than for the C. parapsilosis complex.

  14. Separation and Species Characterization of Complex Compound of Yttrium-90 and Strontium-90 by Paper Electrophoresis

    International Nuclear Information System (INIS)

    Sulaiman; Adang Hardi G; Noor Anis Kundari

    2007-01-01

    The research for species characterization of 90 Y and 90 Sr complex compound have been conducted using variation of buffer, concentration of HCl, electrophoresis operation voltage, time of electrophoresis, and electrophoresis migration media. From many trials, the conclusions are the applicable buffer are tartrate buffer and citrate buffer. These buffers can make a complex compound of 90 Y and there is migration to the anode. But, 90 Sr can’t make any complex compound and migration to the cathode. The optimum concentration of hydrochloride acid is 8 M with tartrate buffer but for citrate buffer, the concentration HCl is 2 M. The hydrochloric acid is used to dissolved the both elements as the mentioned above, but also for making complex ligand. The optimum electrophoresis operation voltage is 200 Volt for the both buffer solution and the duration of electrophoresis operation is 2.5 hours with using tartrate buffer but for citrate buffer the duration is 2 hours. The media of migration which can be used for replacing paper is silica. (author)

  15. Comparison of Phylogeny, Venom Composition and Neutralization by Antivenom in Diverse Species of Bothrops Complex

    Science.gov (United States)

    Peixoto, Pedro S.; Bernardoni, Juliana L.; Oliveira, Sâmella S.; Portes-Junior, José Antonio; Mourão, Rosa Helena V.; Lima-dos-Santos, Isa; Sano-Martins, Ida S.; Chalkidis, Hipócrates M.; Valente, Richard H.; Moura-da-Silva, Ana M.

    2013-01-01

    In Latin America, Bothrops snakes account for most snake bites in humans, and the recommended treatment is administration of multispecific Bothrops antivenom (SAB – soro antibotrópico). However, Bothrops snakes are very diverse with regard to their venom composition, which raises the issue of which venoms should be used as immunizing antigens for the production of pan-specific Bothrops antivenoms. In this study, we simultaneously compared the composition and reactivity with SAB of venoms collected from six species of snakes, distributed in pairs from three distinct phylogenetic clades: Bothrops, Bothropoides and Rhinocerophis. We also evaluated the neutralization of Bothrops atrox venom, which is the species responsible for most snake bites in the Amazon region, but not included in the immunization antigen mixture used to produce SAB. Using mass spectrometric and chromatographic approaches, we observed a lack of similarity in protein composition between the venoms from closely related snakes and a high similarity between the venoms of phylogenetically more distant snakes, suggesting little connection between taxonomic position and venom composition. P-III snake venom metalloproteinases (SVMPs) are the most antigenic toxins in the venoms of snakes from the Bothrops complex, whereas class P-I SVMPs, snake venom serine proteinases and phospholipases A2 reacted with antibodies in lower levels. Low molecular size toxins, such as disintegrins and bradykinin-potentiating peptides, were poorly antigenic. Toxins from the same protein family showed antigenic cross-reactivity among venoms from different species; SAB was efficient in neutralizing the B. atrox venom major toxins. Thus, we suggest that it is possible to obtain pan-specific effective antivenoms for Bothrops envenomations through immunization with venoms from only a few species of snakes, if these venoms contain protein classes that are representative of all species to which the antivenom is targeted. PMID

  16. VEGETATIVE COMPATIBILITY OF Fusarium oxysporum ISOLATED FROM WEEDS IN EASTERN CROATIA

    Directory of Open Access Journals (Sweden)

    Jelena Ilić

    2013-06-01

    Full Text Available Different formae speciales of Fusarium oxysporum are the main causal agent of Fusarium wilts. In 2008 and 2009 we collected F. oxysporum samples from symptomless Abutilon theophrasti, Xanthium strumarium, Chenopodium album, Matricaria perforata, Ambrosia artemisiifolia, Polygonum lapathifolium, Sonchus arvensis, Amaranthus blitoides, Amaranthus retroflexus, Datura stramonium, Sorghum halepense and Hibiscus trionum. Only 16 out of 41 isolates of F. oxysporum yielded nit mutants. The frequency of nit3 mutants was higher (43% than the frequency of nit1 (35% and NitM (22% mutants. Two vegetative compatibility groups (VCGs of F. oxysporum were determined in the complementation tests. These results stress out the problem with isolation of nit mutants and show a high genetic diversity of F. oxysporum isolated from weeds.

  17. An Evaluation of the Species Status of Bactrocera Invadens and the Systematics of the Bactrocera Dorsalis (Diptera: Tephritidae) Complex

    Energy Technology Data Exchange (ETDEWEB)

    Jose, Michael San; Leblanc, Luc; Rubinoff, Daniel [Department of Plant and Environmental Protection Sciences, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Geib, Scott M. [U.S. Department of Agriculture Pacific Basin Agricultural Research Center, Hilo, HI 96720 (United States)

    2014-01-15

    Full text: The genus Bactrocera (Tephritidae) contains 500 species, including many severe pests of fruits and vegetables. Although native to tropical and subtropical areas of Africa, India, Southeast Asia, and Australasia, a number of the pest species, largely members of the Bactrocera dorsalis (Hendel) complex, have become wide- spread through accidental introduction associated with agricultural trade. The B. dorsalis complex includes several morphologically and ecologically similar pests, making species designations uncertain. One of these, Bactrocera invadens Drew, Tsuruta, and White, endemic to Sri Lanka, has spread across Africa in the last decade and become a major agricultural pest. We sequenced one mitochondrial and two nuclear genes from 73 specimens, belonging to 19 species to construct phylogenies and examine species relationships and limits within the genus Bactrocera and several species of the B. dorsalis complex specifically addressing the placement of B. invadens. Results indicate the B. dorsalis complex is polyphyletic. B. invadens and several other species within the B. dorsalis complex (B. dorsalis, Bactrocera papaya Drew and Hancock, and Bactrocera philippinensis (Drew and Hancock) are also paraphyletic with respect to each other and probably represent a single genetically indistinguishable, phenotypically plastic, pest species that has spread throughout the world. (author)

  18. Development of quantitative proteomics using iTRAQ based on the immunological response of Galleria mellonella larvae challenged with Fusarium oxysporum microconidia.

    Directory of Open Access Journals (Sweden)

    Amalia Muñoz-Gómez

    Full Text Available Galleria mellonella has emerged as a potential invertebrate model for scrutinizing innate immunity. Larvae are easy to handle in host-pathogen assays. We undertook proteomics research in order to understand immune response in a heterologous host when challenged with microconidia of Fusarium oxysporum. The aim of this study was to investigate hemolymph proteins that were differentially expressed between control and immunized larvae sets, tested with F. oxysporum at two temperatures. The iTRAQ approach allowed us to observe the effects of immune challenges in a lucid and robust manner, identifying more than 50 proteins, 17 of them probably involved in the immune response. Changes in protein expression were statistically significant, especially when temperature was increased because this was notoriously affected by F. oxysporum 104 or 106 microconidia/mL. Some proteins were up-regulated upon immune fungal microconidia challenge when temperature changed from 25 to 37°C. After analysis of identified proteins by bioinformatics and meta-analysis, results revealed that they were involved in transport, immune response, storage, oxide-reduction and catabolism: 20 from G. mellonella, 20 from the Lepidoptera species and 19 spread across bacteria, protista, fungi and animal species. Among these, 13 proteins and 2 peptides were examined for their immune expression, and the hypothetical 3D structures of 2 well-known proteins, unannotated for G. mellonella, i.e., actin and CREBP, were resolved using peptides matched with Bombyx mori and Danaus plexippus, respectively. The main conclusion in this study was that iTRAQ tool constitutes a consistent method to detect proteins associated with the innate immune system of G. mellonella in response to infection caused by F. oxysporum. In addition, iTRAQ was a reliable quantitative proteomic approach to detect and quantify the expression levels of immune system proteins and peptides, in particular, it was found that 104

  19. Spatial complexity of carcass location influences vertebrate scavenger efficiency and species composition.

    Science.gov (United States)

    Smith, Joshua B; Laatsch, Lauren J; Beasley, James C

    2017-08-31

    Scavenging plays an important role in shaping communities through inter- and intra-specific interactions. Although vertebrate scavenger efficiency and species composition is likely influenced by the spatial complexity of environments, heterogeneity in carrion distribution has largely been disregarded in scavenging studies. We tested this hypothesis by experimentally placing juvenile bird carcasses on the ground and in nests in trees to simulate scenarios of nestling bird carrion availability. We used cameras to record scavengers removing carcasses and elapsed time to removal. Carrion placed on the ground was scavenged by a greater diversity of vertebrates and at > 2 times the rate of arboreal carcasses, suggesting arboreal carrion may represent an important resource to invertebrate scavengers, particularly in landscapes with efficient vertebrate scavenging communities. Nonetheless, six vertebrate species scavenged arboreal carcasses. Rat snakes (Elaphe obsolete), which exclusively scavenged from trees, and turkey vultures (Cathartes aura) were the primary scavengers of arboreal carrion, suggesting such resources are potentially an important pathway of nutrient acquisition for some volant and scansorial vertebrates. Our results highlight the intricacy of carrion-derived food web linkages, and how consideration of spatial complexity in carcass distribution (i.e., arboreal) may reveal important pathways of nutrient acquisition by invertebrate and vertebrate scavenging guilds.

  20. Fisetin as a promising antifungal agent against Cryptocococcus neoformans species complex.

    Science.gov (United States)

    Reis, M P C; Carvalho, C R C; Andrade, F A; Fernandes, O F L; Arruda, W; Silva, M R R

    2016-08-01

    The aim of this study was to investigate the mechanisms of action of fisetin, a flavonol with antifungal activity previously evaluated against the Cryptococcus neoformans species complex. Ergosterol content and flow cytometry analysis were determined for the C. neoformans species complex in the presence of fisetin and ultrastructural analysis of morphology was performed on Cryptococcus gattii and C. neoformans. Decrease in the total cellular ergosterol content after exposure to fisetin ranged from 25·4% after exposure to 128 μg ml(-1) to 21·6% after exposure to 64 μg ml(-1) of fisetin compared with the control (without fisetin). The fisetin effects obtained with flow cytometry showed metabolic impairment, and alterations in its normal morphology caused by fisetin in C. neoformans cells were verified using scanning electron microscopy. Fisetin is a compound that acts in the biosynthesis of ergosterol. Flow cytometry showed that fisetin reduced viability of the metabolically active cells of C. gattii, while morphological changes explain the action of fisetin in inhibiting growth of these fungi. This study supports the idea that fisetin may represent a good starting point for the development of future therapeutic substances for cryptococcosis. © 2016 The Society for Applied Microbiology.

  1. Cryptic lineage diversity, body size divergence, and sympatry in a species complex of Australian lizards (Gehyra).

    Science.gov (United States)

    Moritz, Craig C; Pratt, Renae C; Bank, Sarah; Bourke, Gayleen; Bragg, Jason G; Doughty, Paul; Keogh, J Scott; Laver, Rebecca J; Potter, Sally; Teasdale, Luisa C; Tedeschi, Leonardo G; Oliver, Paul M

    2018-01-01

    Understanding the joint evolutionary and ecological underpinnings of sympatry among close relatives remains a key challenge in biology. This problem can be addressed through joint phylogenomic and phenotypic analysis of complexes of closely related lineages within, and across, species and hence representing the speciation continuum. For a complex of tropical geckos from northern Australia-Gehyra nana and close relatives-we combine mtDNA phylogeography, exon-capture sequencing, and morphological data to resolve independently evolving lineages and infer their divergence history and patterns of morphological evolution. Gehyra nana is found to include nine divergent lineages and is paraphyletic with four other species from the Kimberley region of north-west Australia. Across these 13 taxa, 12 of which are restricted to rocky habitats, several lineages overlap geographically, including on the diverse Kimberley islands. Morphological evolution is dominated by body size shifts, and both body size and shape have evolved gradually across the group. However, larger body size shifts are observed among overlapping taxa than among closely related parapatric lineages of G. nana, and sympatric lineages are more divergent than expected at random. Whether elevated body size differences among sympatric lineages are due to ecological sorting or character displacement remains to be determined. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  2. The Possibility of Ce3+ and Mn2+ Complex Ions Formation With Iodine Species in a Dushman Reaction

    Directory of Open Access Journals (Sweden)

    Iurie Ungureanu

    2018-06-01

    Full Text Available This contribution presents investigations into possible effects of Ce3+ and Mn2+ on the reduction of UV-spectral signal for I3- observed e.g. in the Dushman reaction. The potential of the metal ions to form complexes with iodine-containing species was analysed. It was shown that no complex ions are formed between Ce3+ and Mn2+ metals ions with IO3-, I-, I2 species. Only the formation of a very weak CeI32+ complex ion was found to occur. An effect of a complex formation on the studied systems could be excluded.

  3. Occupancy modeling and estimation of the holiday darter species complex within the Etowah River system

    Science.gov (United States)

    Anderson, Gregory B.; Freeman, Mary C.; Hagler, Megan M.; Freeman, Byron J.

    2012-01-01

    Documenting the status of rare fishes is a crucial step in effectively managing populations and implementing regulatory mechanisms of protection. In recent years, site occupancy has become an increasingly popular metric for assessing populations, but species distribution models that do not account for imperfect detection can underestimate the proportion of sites occupied and the strength of the relationship with a hypothesized covariate. However, valid detection requires temporal or spatial replication, which is often not feasible due to logistical or budget constraints. In this study, we used a method that allowed for spatial replication during a single visit to evaluate the current status of the holiday darter species complex, Etheostoma sp. cf. E. brevirostrum, within the Etowah River system. Moreover, the modeling approach used in this study facilitated comparisons of factors influencing stream occupancy as well as species detection within sites. The results suggest that there is less habitat available for the Etowah holiday darter form (Etheostoma sp. cf. E. brevirostrum B) than for the Amicalola holiday darter form (Etheostoma sp. cf. E. brevirostrum A). Additionally, occupancy models suggest that even small decreases in forest cover within these headwater systems adversely affect holiday darter populations.

  4. Niche divergence builds the case for ecological speciation in skinks of the Plestiodon skiltonianus species complex

    Science.gov (United States)

    Wogan, Guinevere O.U.; Richmond, Jonathan Q.

    2015-01-01

    Adaptation to different thermal environments has the potential to cause evolutionary changes that are sufficient to drive ecological speciation. Here, we examine whether climate-based niche divergence in lizards of the Plestiodon skiltonianus species complex is consistent with the outcomes of such a process. Previous work on this group shows that a mechanical sexual barrier has evolved between species that differ mainly in body size and that the barrier may be a by-product of selection for increased body size in lineages that have invaded xeric environments; however, baseline information on niche divergence among members of the group is lacking. We quantified the climatic niche using mechanistic physiological and correlative niche models and then estimated niche differences among species using ordination techniques and tests of niche overlap and equivalency. Our results show that the thermal niches of size-divergent, reproductively isolated morphospecies are significantly differentiated and that precipitation may have been as important as temperature in causing increased shifts in body size in xeric habitats. While these findings alone do not demonstrate thermal adaptation or identify the cause of speciation, their integration with earlier genetic and behavioral studies provides a useful test of phenotype–environment associations that further support the case for ecological speciation in these lizards.

  5. The tomato wilt fungus Fusarium oxysporum f. sp. lycopersici shares common ancestors with nonpathogenic F. oxysporum isolated from wild tomatoes in the Peruvian Andes.

    Science.gov (United States)

    Inami, Keigo; Kashiwa, Takeshi; Kawabe, Masato; Onokubo-Okabe, Akiko; Ishikawa, Nobuko; Pérez, Enrique Rodríguez; Hozumi, Takuo; Caballero, Liliana Aragón; de Baldarrago, Fatima Cáceres; Roco, Mauricio Jiménez; Madadi, Khalid A; Peever, Tobin L; Teraoka, Tohru; Kodama, Motoichiro; Arie, Tsutomu

    2014-01-01

    Fusarium oxysporum is an ascomycetous fungus that is well-known as a soilborne plant pathogen. In addition, a large population of nonpathogenic F. oxysporum (NPF) inhabits various environmental niches, including the phytosphere. To obtain an insight into the origin of plant pathogenic F. oxysporum, we focused on the tomato (Solanum lycopersicum) and its pathogenic F. oxysporum f. sp. lycopersici (FOL). We collected F. oxysporum from wild and transition Solanum spp. and modern cultivars of tomato in Chile, Ecuador, Peru, Mexico, Afghanistan, Italy, and Japan, evaluated the fungal isolates for pathogenicity, VCG, mating type, and distribution of SIX genes related to the pathogenicity of FOL, and constructed phylogenies based on ribosomal DNA intergenic spacer sequences. All F. oxysporum isolates sampled were genetically more diverse than FOL. They were not pathogenic to the tomato and did not carry SIX genes. Certain NPF isolates including those from wild Solanum spp. in Peru were grouped in FOL clades, whereas most of the NPF isolates were not. Our results suggested that the population of NPF isolates in FOL clades gave rise to FOL by gaining pathogenicity.

  6. Species delimitation in the Gehyra nana (Squamata: Gekkonidae) complex: cryptic and divergent morphological evolution in the Australian Monsoonal Tropics, with the description of four new species.

    Science.gov (United States)

    Doughty, Paul; Bourke, Gayleen; Tedeschi, Leonardo G; Pratt, Renae C; Oliver, Paul M; Palmer, Russell A; Moritz, Craig

    2018-04-04

    Recent advances in molecular genetic techniques and increased fine scale sampling in the Australian Monsoonal Tropics (AMT) have provided new impetus to reassess species boundaries in the Gehyra nana species complex, a clade of small-bodied, saxicolous geckos which are widely distributed across northern Australia. A recent phylogenomic analysis revealed eight deeply divergent lineages that occur as a series of overlapping distributions across the AMT and which, as a whole, are paraphyletic with four previously described species. Several of these lineages currently included in G. nana are phenotypically distinct, while others are highly conservative morphologically. Here we use an integrated approach to explore species delimitation in this complex. We redefine G. nana as a widespread taxon with complex genetic structure across the Kimberley of Western Australia and Top End of the Northern Territory, including a lineage with mtDNA introgressed from the larger-bodied G. multiporosa. We describe four new species with more restricted distributions within the G. nana complex. The new species are phylogenetically divergent and morphologically diagnosable, and include the relatively cryptic G. paranana sp. nov. from the western Northern Territory, the large-bodied G. pseudopunctata sp. nov. from the southern Kimberley ranges, G. granulum sp. nov., a small-bodied form with granules on the proximal lamellae from the north-west and southern Kimberley ranges and the small-bodied G. pluraporosa sp. nov. restricted to the northern Kimberley. Our revision largely stabilises the taxonomy of the G. nana complex, although further analyses of species limits among the remaining mostly parapatric lineages of G. nana sensu stricto are warranted.

  7. Tempo and mode of recurrent polyploidization in the Carassius auratus species complex (Cypriniformes, Cyprinidae).

    Science.gov (United States)

    Luo, J; Gao, Y; Ma, W; Bi, X-y; Wang, S-y; Wang, J; Wang, Y-q; Chai, J; Du, R; Wu, S-f; Meyer, A; Zan, R-g; Xiao, H; Murphy, R W; Zhang, Y-p

    2014-04-01

    Polyploidization is an evolutionarily rare but important mechanism in both plants and animals because it increases genetic diversity. Goldfish of the Carassius auratus species complex can be tetraploids, hexaploids and octaploids. Polyploidization events have occurred repeatedly in goldfish, yet the extent of this phenomenon and its phyletic history are poorly understood. We explore the origin, tempo and frequency of polyploidization in Chinese and Japanese goldfish using both mitochondrial (mtDNA) and nuclear DNA sequences from up to 1202 individuals including the outgroup taxon, Cyprinus carpio. Analyses of de novo nuclear gene data resolve two clusters of alleles and the pattern supports the prior hypothesis of an ancient allotetraploidization for Carassius. Alleles shared by tetraploid and hexaploid individuals indicate recent autoploidizations within the C. auratus complex. Sympatric tetraploids and hexaploids share mtDNA haplotypes and these frequently occur independently within six well-supported lineages and sublineages on a small spatial scale. Gene flow estimates (Fst values) indicate that hexaploids differ only slightly from sympatric tetraploids, if at all. In contrast, allopatric populations of tetraploids and hexaploids differ from one another to a far greater extent. Gene flow between sampled localities appears to be limited. Coalescence-based time estimations for hexaploids reveal that the oldest lineage within any sampled locality is around one million years old, which is very young. Sympatric, recurrent autoploidization occurs in all sampled populations of the C. auratus complex. Goldfish experience polyploidization events more frequently than any other vertebrate.

  8. A Natural Mutation Involving both Pathogenicity and Perithecium Formation in the Fusarium graminearum Species Complex

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    Haruhisha Suga

    2016-12-01

    Full Text Available Members of the Fusarium graminearum species complex (Fg complex or FGSC are the primary pathogens causing Fusarium head blight in wheat and barley worldwide. A natural pathogenicity mutant (strain 0225022 was found in a sample of the Fg complex collected in Japan. The mutant strain did not induce symptoms in wheat spikes beyond the point of inoculation, and did not form perithecia. No segregation of phenotypic deficiencies occurred in the progenies of a cross between the mutant and a fully pathogenic wild-type strain, which suggested that a single genetic locus controlled both traits. The locus was mapped to chromosome 2 by using sequence-tagged markers; and a deletion of ∼3 kb was detected in the mapped region of the mutant strain. The wild-type strain contains the FGSG_02810 gene, encoding a putative glycosylphosphatidylinositol anchor protein, in this region. The contribution of FGSG_02810 to pathogenicity and perithecium formation was confirmed by complementation in the mutant strain using gene transfer, and by gene disruption in the wild-type strain.

  9. Mycobacterium arupense, Mycobacterium heraklionense, and a Newly Proposed Species, "Mycobacterium virginiense" sp. nov., but Not Mycobacterium nonchromogenicum, as Species of the Mycobacterium terrae Complex Causing Tenosynovitis and Osteomyelitis.

    Science.gov (United States)

    Vasireddy, Ravikiran; Vasireddy, Sruthi; Brown-Elliott, Barbara A; Wengenack, Nancy L; Eke, Uzoamaka A; Benwill, Jeana L; Turenne, Christine; Wallace, Richard J

    2016-05-01

    Mycobacterium terrae complex has been recognized as a cause of tenosynovitis, with M. terrae and Mycobacterium nonchromogenicum reported as the primary etiologic pathogens. The molecular taxonomy of the M. terrae complex causing tenosynovitis has not been established despite approximately 50 previously reported cases. We evaluated 26 isolates of the M. terrae complex associated with tenosynovitis or osteomyelitis recovered between 1984 and 2014 from 13 states, including 5 isolates reported in 1991 as M. nonchromogenicum by nonmolecular methods. The isolates belonged to three validated species, one new proposed species, and two novel related strains. The majority of isolates (20/26, or 77%) belonged to two recently described species: Mycobacterium arupense (10 isolates, or 38%) and Mycobacterium heraklionense (10 isolates, or 38%). Three isolates (12%) had 100% sequence identity to each other by 16S rRNA and 99.3 to 100% identity by rpoB gene region V sequencing and represent a previously undescribed species within the M. terrae complex. There were no isolates of M. terrae or M. nonchromogenicum, including among the five isolates reported in 1991. The 26 isolates were susceptible to clarithromycin (100%), rifabutin (100%), ethambutol (92%), and sulfamethoxazole or trimethoprim-sulfamethoxazole (70%). The current study suggests that M. arupense, M. heraklionense, and a newly proposed species ("M. virginiense" sp. nov.; proposed type strain MO-233 [DSM 100883, CIP 110918]) within the M. terrae complex are the major causes of tenosynovitis and osteomyelitis in the United States, with little change over 20 years. Species identification within this complex requires sequencing methods. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  10. Identification and diversity of Fusarium species isolated from tomato fruits

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    Murad Nur Baiti Abd

    2016-07-01

    Full Text Available Fruit rot of tomato is a serious disease caused by Fusarium species. Sampling was conducted throughout Selangor, Malaysia and fungal species identification was conducted based on morphological and gene encoding translation elongation factor 1-α (tef1-α sequence analysis. Five species of Fusarium were discovered namely F. oxysporum (including F. oxysporum f. sp. lycopersici, F. solani, F. equiseti, F. proliferatum and F. verticillioides. Our results provide additional information regarding the diversity of Fusarium species associated with fruit rot disease of tomato.

  11. Fusarium Oxysporum el hongo que nos falta conocer

    Directory of Open Access Journals (Sweden)

    Emira Garces De Granada

    2001-01-01

    Full Text Available Fusarium oxysporum es un hongo que se presenta principalmente como saprófito en el suelo, o también como patógeno especializado, denominado forma especial (f.sp., según la planta hospedante u hospedantes relacionados que afecte. Es posible distinguir patotipos o razas fisiológicas de una misma forma especial, cuando se determima la variedad de la especie vegetal que ataca y aun en poblaciones clonales al analizar características moleculares (DNA, fingerprint, RFLPs , RAPDs . No obstante, con referencia a la especificidad como fitopatóneno, pruebas de patogenicidad realizadas en condiciones de invernadero con el hongo causante del marchitamiento vascular en tomate (Fusarium oxysporum f. sp. . lycopersici causó infección en plantas de clavel y de rábano en 20 y 47% respectivamente. Mientras, Gardini (1993,  en ensayos realizados directamemte en el suelo natural, con aislamientos de Fusarium oxysporum  f. sp. erythoxyli, causante de marchitez vascular en plantas de coca, produjo en éstas la enfermedad  en 100% y en 25% y 12.5% en achote y tomate, lo que cuestiona la especificidad del hongo, y su utilización como biocontrolador.  Así mismo, la alta sobrevivencia de sus clamidosporas,  resistentes a la degradac ión química y microbiológica,  y el registro como patógeno en animales incluyendo el hombre,  (produce afecciones oftálmicas, dérmicas y tóxinas determinan que no debe usars el hongo fitopatógeno de la coca como “micoherbicida” en plantaciones de coca, pues no sólo afecta a otras especies del género Erythroxylon no productoras del alcaloide, sino a plantas alimenticias y al hombre.

  12. Direct ethanol conversion of pretreated straw by Fusarium oxysporum

    Energy Technology Data Exchange (ETDEWEB)

    Christakopoulos, P.; Koullas, D.P.; Kekos, D.; Koukios, E.G.; Macris, B.J. (National Technical Univ., Athens (GR). Dept. of Chemical Engineering)

    1991-01-01

    Factors affecting the direct conversion of alkali pretreated straw to ethanol by Fusarium oxysporum F3 were investigated and the alkali level used for pretreatment and the degree of delignification of straw were found to be the most important. A linear correlation between ethanol yield and both the degree of straw delignification and the alkali level was observed. At optimum delignified straw concentration (4% w/v), a maximum ethanol yield of 0.275 g ethanol g{sup -1} of straw was obtained corresponding to 67.8% of the theoretical yield. (author).

  13. Nondermatophytic onychomycosis by Fusarium oxysporum in an immunocompetent host.

    Science.gov (United States)

    Shah, S R; Dalal, B D; Modak, M S

    2016-03-01

    Fusarium onychomycosis is not uncommon in tropical countries but is worth reporting. We report a case of nondermatophytic onychomycosis by Fusarium oxysporum in an immunocompetent woman from Buldhana district of Maharashtra (India). Bilateral involvement of great toe nail, chronic duration and acquisition of infection due to peculiar practice of daily pasting floors with mud and dung, is interesting. The case was successfully treated with topical and oral terbinafine with a dose of 250 mg daily for 3 weeks. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  14. Development of a Single Locus Sequence Typing (SLST) Scheme for Typing Bacterial Species Directly from Complex Communities.

    Science.gov (United States)

    Scholz, Christian F P; Jensen, Anders

    2017-01-01

    The protocol describes a computational method to develop a Single Locus Sequence Typing (SLST) scheme for typing bacterial species. The resulting scheme can be used to type bacterial isolates as well as bacterial species directly from complex communities using next-generation sequencing technologies.

  15. Unusual distribution of Burkholderia cepacia complex species in Danish cystic fibrosis clinics may stem from restricted transmission between patients

    DEFF Research Database (Denmark)

    Nørskov-Lauritsen, Niels; Johansen, Helle Krogh; Fenger, Mette G

    2010-01-01

    Forty-four of 48 Burkholderia cepacia complex strains cultured from Danish cystic fibrosis patients were Burkholderia multivorans, a distribution of species that has not been reported before. Although cases of cross infections were demonstrated, no major epidemic clone was found. The species...

  16. Flat and complex temperate reefs provide similar support for fish: Evidence for a unimodal species-habitat relationship.

    Directory of Open Access Journals (Sweden)

    Avery B Paxton

    Full Text Available Structural complexity, a form of habitat heterogeneity, influences the structure and function of ecological communities, generally supporting increased species density, richness, and diversity. Recent research, however, suggests the most complex habitats may not harbor the highest density of individuals and number of species, especially in areas with elevated human influence. Understanding nuances in relationships between habitat heterogeneity and ecological communities is warranted to guide habitat-focused conservation and management efforts. We conducted fish and structural habitat surveys of thirty warm-temperate reefs on the southeastern US continental shelf to quantify how structural complexity influences fish communities. We found that intermediate complexity maximizes fish abundance on natural and artificial reefs, as well as species richness on natural reefs, challenging the current paradigm that abundance and other fish community metrics increase with increasing complexity. Naturally occurring rocky reefs of flat and complex morphologies supported equivalent abundance, biomass, species richness, and community composition of fishes. For flat and complex morphologies of rocky reefs to receive equal consideration as essential fish habitat (EFH, special attention should be given to detecting pavement type rocky reefs because their ephemeral nature makes them difficult to detect with typical seafloor mapping methods. Artificial reefs of intermediate complexity also maximized fish abundance, but human-made structures composed of low-lying concrete and metal ships differed in community types, with less complex, concrete structures supporting lower numbers of fishes classified largely as demersal species and metal ships protruding into the water column harboring higher numbers of fishes, including more pelagic species. Results of this study are essential to the process of evaluating habitat function provided by different types and shapes of

  17. Recurrent evolution of host and vector association in bacteria of the Borrelia burgdorferi sensu lato species complex.

    Science.gov (United States)

    Becker, Noémie S; Margos, Gabriele; Blum, Helmut; Krebs, Stefan; Graf, Alexander; Lane, Robert S; Castillo-Ramírez, Santiago; Sing, Andreas; Fingerle, Volker

    2016-09-15

    The Borrelia burgdorferi sensu lato (s.l.) species complex consists of tick-transmitted bacteria and currently comprises approximately 20 named and proposed genospecies some of which are known to cause Lyme Borreliosis. Species have been defined via genetic distances and ecological niches they occupy. Understanding the evolutionary relationship of species of the complex is fundamental to explaining patterns of speciation. This in turn forms a crucial basis to frame testable hypotheses concerning the underlying processes including host and vector adaptations. Illumina Technology was used to obtain genome-wide sequence data for 93 strains of 14 named genospecies of the B. burgdorferi species complex and genomic data already published for 18 additional strain (including one new species) was added. Phylogenetic reconstruction based on 114 orthologous single copy genes shows that the genospecies represent clearly distinguishable taxa with recent and still ongoing speciation events apparent in Europe and Asia. The position of Borrelia species in the phylogeny is consistent with host associations constituting a major driver for speciation. Interestingly, the data also demonstrate that vector associations are an additional driver for diversification in this tick-borne species complex. This is particularly obvious in B. bavariensis, a rodent adapted species that has diverged from the bird-associated B. garinii most likely in Asia. It now consists of two populations one of which most probably invaded Europe following adaptation to a new vector (Ixodes ricinus) and currently expands its distribution range. The results imply that genotypes/species with novel properties regarding host or vector associations have evolved recurrently during the history of the species complex and may emerge at any time. We suggest that the finding of vector associations as a driver for diversification may be a general pattern for tick-borne pathogens. The core genome analysis presented here

  18. Fusarium oxysporum f. sp. dianthi virus 1 accumulation is correlated with changes in virulence and other phenotypic traits of its fungal host.

    Science.gov (United States)

    Lemus-Minor, Carlos German; Cañizares-Nolasco, Carmen; García-Pedrajas, Maria D D; Pérez-Artés, Encarnación

    2018-03-08

    Fusarium oxysporum f. sp. dianthi virus 1 (FodV1) was detected in isolate Fod 116 (Fod 116V + ) of Fusarium oxysporum f. sp. dianthi (Fod), reaching such a high accumulation level that it was clearly visible after agarose gel electrophoresis of total DNA extracts. FodV1 consists of four double-stranded RNA segments, that correspond to a new mycovirus in the Chrysoviridae family. We obtained an isolate of Fod 116 (Fod 116V - ) with only a residual level of FodV1 RNA accumulation by single-conidia selection. Compared to the Fod 116V - , isolate Fod 116V + showed significant phenotypic alterations in vegetative growth and virulence. The presence of a high titer of mycovirus FodV1 thus associated with a modified morphology and a reduced growth of the colonies on solid medium, and with a diminished conidiation in liquid medium. Inoculation of four susceptible carnation cultivars with either Fod 116V - or Fod 116V + showed that the presence of a high titer of FodV1 was also correlated with a significantly reduced virulence of its fungal host. All the results suggest that FodV1 could be associated with hypovirulence, identifying it as a potential biocontrol agent against Fusarium wilt of carnation. This is the first report of a mycovirus potentially associated to the induction of hypovirulence in the species Fusarium oxysporum.

  19. Risk levels of invasive Fusarium oxysporum f. sp. in areas suitable for date palm (Phoenix dactylifera) cultivation under various climate change projections.

    Science.gov (United States)

    Shabani, Farzin; Kumar, Lalit

    2013-01-01

    Global climate model outputs involve uncertainties in prediction, which could be reduced by identifying agreements between the output results of different models, covering all assumptions included in each. Fusarium oxysporum f.sp. is an invasive pathogen that poses risk to date palm cultivation, among other crops. Therefore, in this study, the future distribution of invasive Fusarium oxysporum f.sp., confirmed by CSIRO-Mk3.0 (CS) and MIROC-H (MR) GCMs, was modeled and combined with the future distribution of date palm predicted by the same GCMs, to identify areas suitable for date palm cultivation with different risk levels of invasive Fusarium oxysporum f.sp., for 2030, 2050, 2070 and 2100. Results showed that 40%, 37%, 33% and 28% areas projected to become highly conducive to date palm are under high risk of its lethal fungus, compared with 37%, 39%, 43% and 42% under low risk, for the chosen years respectively. Our study also indicates that areas with marginal risk will be limited to 231, 212, 186 and 172 million hectares by 2030, 2050, 2070 and 2100. The study further demonstrates that CLIMEX outputs refined by a combination of different GCMs results of different species that have symbiosis or parasite relationship, ensure that the predictions become robust, rather than producing hypothetical findings, limited purely to publication.

  20. Three Fusarium oxysporum mitogen-activated protein kinases (MAPKs) have distinct and complementary roles in stress adaptation and cross-kingdom pathogenicity.

    Science.gov (United States)

    Segorbe, David; Di Pietro, Antonio; Pérez-Nadales, Elena; Turrà, David

    2017-09-01

    Mitogen-activated protein kinase (MAPK) cascades mediate cellular responses to environmental signals. Previous studies in the fungal pathogen Fusarium oxysporum have revealed a crucial role of Fmk1, the MAPK orthologous to Saccharomyces cerevisiae Fus3/Kss1, in vegetative hyphal fusion and plant infection. Here, we genetically dissected the individual and combined contributions of the three MAPKs Fmk1, Mpk1 and Hog1 in the regulation of development, stress response and virulence of F. oxysporum on plant and animal hosts. Mutants lacking Fmk1 or Mpk1 were affected in reactive oxygen species (ROS) homeostasis and impaired in hyphal fusion and aggregation. Loss of Mpk1 also led to increased sensitivity to cell wall and heat stress, which was exacerbated by simultaneous inactivation of Fmk1, suggesting that both MAPKs contribute to cellular adaptation to high temperature, a prerequisite for mammalian pathogens. Deletion of Hog1 caused increased sensitivity to hyperosmotic stress and resulted in partial rescue of the restricted colony growth phenotype of the mpk1Δ mutant. Infection assays on tomato plants and the invertebrate animal host Galleria mellonella revealed distinct and additive contributions of the different MAPKs to virulence. Our results indicate that positive and negative cross-talk between the three MAPK pathways regulates stress adaptation, development and virulence in the cross-kingdom pathogen F. oxysporum. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  1. Risk Levels of Invasive Fusarium oxysporum f. sp. in Areas Suitable for Date Palm (Phoenix dactylifera) Cultivation under Various Climate Change Projections

    Science.gov (United States)

    Shabani, Farzin; Kumar, Lalit

    2013-01-01

    Global climate model outputs involve uncertainties in prediction, which could be reduced by identifying agreements between the output results of different models, covering all assumptions included in each. Fusarium oxysporum f.sp. is an invasive pathogen that poses risk to date palm cultivation, among other crops. Therefore, in this study, the future distribution of invasive Fusarium oxysporum f.sp., confirmed by CSIRO-Mk3.0 (CS) and MIROC-H (MR) GCMs, was modeled and combined with the future distribution of date palm predicted by the same GCMs, to identify areas suitable for date palm cultivation with different risk levels of invasive Fusarium oxysporum f.sp., for 2030, 2050, 2070 and 2100. Results showed that 40%, 37%, 33% and 28% areas projected to become highly conducive to date palm are under high risk of its lethal fungus, compared with 37%, 39%, 43% and 42% under low risk, for the chosen years respectively. Our study also indicates that areas with marginal risk will be limited to 231, 212, 186 and 172 million hectares by 2030, 2050, 2070 and 2100. The study further demonstrates that CLIMEX outputs refined by a combination of different GCMs results of different species that have symbiosis or parasite relationship, ensure that the predictions become robust, rather than producing hypothetical findings, limited purely to publication. PMID:24340100

  2. Potential of Burkholderia seminalis TC3.4.2R3 as Biocontrol Agent Against Fusarium oxysporum Evaluated by Mass Spectrometry Imaging

    Science.gov (United States)

    Araújo, Francisca Diana da Silva; Araújo, Welington Luiz; Eberlin, Marcos Nogueira

    2017-05-01

    Species of genus Burkholderia display different interaction profiles in the environment, causing either several diseases in plants and animals or being beneficial to some plants, promoting their growth, and suppressing phytopathogens. Burkholderia spp. also produce many types of biomolecules with antimicrobial activity, which may be commercially used to protect crops of economic interest, mainly against fungal diseases. Herein we have applied matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) to investigate secondary metabolites produced by B. seminalis TC3.4.2R3 in monoculture and coculture with plant pathogen Fusarium oxysporum. The siderophore pyochelin and the rhamnolipid Rha-Rha-C15-C14 were detected in wild-type B. seminalis strain, and their productions were found to vary in mutant strains carrying disruptions in gene clusters associated with antimicrobial compounds. Two mycotoxins were detected in F. oxysporum. During coculture with B. seminalis, metabolites probably related to defense mechanisms of these microorganisms were observed in the interspecies interaction zone. Our findings demonstrate the effective application of MALDI-MSI in the detection of bioactive molecules involved in the defense mechanism of B. seminalis, and these findings suggest the potential use of this bacterium in the biocontrol of plant diseases caused by F. oxysporum.

  3. Characterization of siderophore produced by Pseudomonas syringae BAF.1 and its inhibitory effects on spore germination and mycelium morphology of Fusarium oxysporum.

    Science.gov (United States)

    Yu, Sumei; Teng, Chunying; Liang, Jinsong; Song, Tao; Dong, Liying; Bai, Xin; Jin, Yu; Qu, Juanjuan

    2017-11-01

    In this study, an antagonistic bacterium against Fusarium oxysporum was identified and designated as Pseudomonas syringae strain BAF.1 on the basis of 16S rDNA sequence analysis and physiological-biochemical characteristics. It produced catechol-species siderophore at a molecular weight of 488.59 Da and a maximum amount of 55.27 μg/ml with glucose as a carbon source and asparagine as a nitrogen source at a C/N ratio of 10:1, 30°C and pH 7. The siderophore exhibited prominent antagonistic activity against Fusarium oxysporum with a maximum inhibition rate of 95.24% and had also suppressive effects on other kinds of 11 phytopathogenic fungi in the absence of FeCl 3 ·6H 2 O. Spore germination was completely inhibited by 50 μl of the siderophorecontaining solution, and the ultrastructures of mycelia and spores were also considerably suppressed by siderophore treatment as established by electron microscopy observation. These results indicate that the siderophore produced by Pseudomonas syringae BAF.1 could be potentially used for biocontrol of pathogenic Fusarium oxysporum.

  4. Multilocus analysis using putative fungal effectors to describe a population of Fusarium oxysporum from sugar beet.

    Science.gov (United States)

    Covey, Paul A; Kuwitzky, Brett; Hanson, Mia; Webb, Kimberly M

    2014-08-01

    Sugar beet (Beta vulgaris) Fusarium yellows is caused by Fusarium oxysporum f. sp. betae and can lead to significant reductions in root yield, sucrose percentage, juice purity, and storability. F. oxysporum f. sp. betae can be highly variable and many F. oxysporum strains isolated from symptomatic sugar beet are nonpathogenic. Identifying pathogenicity factors and their diversity in the F. oxysporum f. sp. betae population could further understanding of how this pathogen causes disease and potentially provide molecular markers to rapidly identify pathogenic isolates. This study used several previously described fungal effector genes (Fmk1, Fow1, Pda1, PelA, PelD, Pep1, Prt1, Rho1, Sge1, Six1, Six6, Snf1, and Ste12) as genetic markers, in a population of 26 pathogenic and nonpathogenic isolates of F. oxysporum originally isolated from symptomatic sugar beet. Of the genes investigated, six were present in all F. oxysporum isolates from sugar beet (Fmk1, Fow1, PelA, Rho1, Snf1, and Ste12), and seven were found to be dispersed within the population (Pda1, PelD, Pep1, Prt1, Sge1, Six1, and Six6). Of these, Fmk1, Fow1, PelA, Rho1, Sge1, Snf1, and Ste12 were significant in relating clade designations and PelD, and Prt1 were significant for correlating with pathogenicity in F. oxysporum f. sp. betae.

  5. The Fusarium oxysporum effector Six6 contributes to virulence and suppresses I-2-mediated cell death.

    Science.gov (United States)

    Gawehns, F; Houterman, P M; Ichou, F Ait; Michielse, C B; Hijdra, M; Cornelissen, B J C; Rep, M; Takken, F L W

    2014-04-01

    Plant pathogens secrete effectors to manipulate their host and facilitate colonization. Fusarium oxysporum f. sp. lycopersici is the causal agent of Fusarium wilt disease in tomato. Upon infection, F. oxysporum f. sp. lycopersici secretes numerous small proteins into the xylem sap (Six proteins). Most Six proteins are unique to F. oxysporum, but Six6 is an exception; a homolog is also present in two Colletotrichum spp. SIX6 expression was found to require living host cells and a knockout of SIX6 in F. oxysporum f. sp. lycopersici compromised virulence, classifying it as a genuine effector. Heterologous expression of SIX6 did not affect growth of Agrobacterium tumefaciens in Nicotiana benthamiana leaves or susceptibility of Arabidopsis thaliana toward Verticillium dahliae, Pseudomonas syringae, or F. oxysporum, suggesting a specific function for F. oxysporum f. sp. lycopersici Six6 in the F. oxysporum f. sp. lycopersici- tomato pathosystem. Remarkably, Six6 was found to specifically suppress I-2-mediated cell death (I2CD) upon transient expression in N. benthamiana, whereas it did not compromise the activity of other cell-death-inducing genes. Still, this I2CD suppressing activity of Six6 does not allow the fungus to overcome I-2 resistance in tomato, suggesting that I-2-mediated resistance is independent from cell death.

  6. Complex offspring size effects: variations across life stages and between species.

    Science.gov (United States)

    Sun, Zhao; Hamel, Jean-François; Parrish, Christopher C; Mercier, Annie

    2015-03-01

    Classical optimality models of offspring size and number assume a monotonically increasing relationship between offspring size and performance. In aquatic organisms with complex life cycles, the size-performance function is particularly hard to grasp because measures of performance are varied and their relationships with size may not be consistent throughout early ontogeny. Here, we examine size effects in premetamorphic (larval) and postmetamorphic (juvenile) stages of brooding marine animals and show that they vary contextually in strength and direction during ontogeny and among species. Larger offspring of the sea anemone Urticina felina generally outperformed small siblings at the larval stage (i.e., greater settlement and survival rates under suboptimal conditions). However, results differed when analyses were conducted at the intrabrood versus across-brood levels, suggesting that the relationship between larval size and performance is mediated by parentage. At the juvenile stage (15 months), small offspring were less susceptible than large ones to predation by subadult nudibranchs and both sizes performed similarly when facing adult nudibranchs. In a sympatric species with a different life history (Aulactinia stella), all juveniles suffered similar predation rates by subadult nudibranchs, but smaller juveniles performed better (lower mortalities) when facing adult nudibranchs. Size differences in premetamorphic performance of U. felina were linked to total lipid contents of larvae, whereas size-specific predation of juvenile stages followed the general predictions of the optimal foraging strategy. These findings emphasize the challenge in gathering empirical support for a positive monotonic size-performance function in taxa that exhibit complex life cycles, which are dominant in the sea.

  7. AÇÃO ANTIFÚNGICA in vitro DE ISOLADOS DE Bacillu s sp. SOBRE Fusarium oxysporum f. sp. lycopersici

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    ODENILSON DE DEUS RIBEIRO LIMA

    2014-01-01

    Full Text Available This study aimed to evaluate antagonism and metabolites produced by different species of Ba- cillus in the inhibition of mycelial growth in vitro against F. oxysporum f. sp . lycopersici . For evaluating the antagonism of Bacillus spp. F. oxysporum f. sp . lycopersici was performed pairing of fungus and bacteria by the method of the circle. In the method for detection for the quality for thermostable metabolites liquids. Media BD were used for growth of the isolated Bacillus sp. And incubated for 15 days. After this period, was added 3 g of agar in each flask, and autoclaved broth and poured into Petri dishes. In the center of the plates were placed discs culture of the pathogen. The experimental design was completely randomized with 11 treatments and six repetitions in both experiments. Statistical difference was found between the isolate and the control. Special mention to strains B12 ( Bacillus sp., B41 ( B. cereus , B22' ( B.pentothenticus , B45 ( B. cereus , B47 ( B. cereus that exhibited the lowest average diameter of the colony. To study the inhibition of mycelial growth of F. oxysporum f. sp. lycopersici by thermostatable metabolites five differ statistically from the control they are: B35 ( B. pumilus , B47 ( B. cereus , B22' ( B. pentothenticus , B12 ( Bacillus sp. and B41 ( B. cereus the latter two treatments showed the best results of the pathogen colony diameters and 3.81 to 2.89 cm, respective- ly. B12 and B41 Isolates showed that their antibiotic products were able to inhibit 67.88 % and 57,66 % of F. oxysporum f. sp. lycopersici . These results highlight the possibility of using isolates of the genus Bacillus in the fight against fusarium wilt in tomato.

  8. Plastome Sequence Determination and Comparative Analysis for Members of the Lolium-Festuca Grass Species Complex

    Science.gov (United States)

    Hand, Melanie L.; Spangenberg, German C.; Forster, John W.; Cogan, Noel O. I.

    2013-01-01

    Chloroplast genome sequences are of broad significance in plant biology, due to frequent use in molecular phylogenetics, comparative genomics, population genetics, and genetic modification studies. The present study used a second-generation sequencing approach to determine and assemble the plastid genomes (plastomes) of four representatives from the agriculturally important Lolium-Festuca species complex of pasture grasses (Lolium multiflorum, Festuca pratensis, Festuca altissima, and Festuca ovina). Total cellular DNA was extracted from either roots or leaves, was sequenced, and the output was filtered for plastome-related reads. A comparison between sources revealed fewer plastome-related reads from root-derived template but an increase in incidental bacterium-derived sequences. Plastome assembly and annotation indicated high levels of sequence identity and a conserved organization and gene content between species. However, frequent deletions within the F. ovina plastome appeared to contribute to a smaller plastid genome size. Comparative analysis with complete plastome sequences from other members of the Poaceae confirmed conservation of most grass-specific features. Detailed analysis of the rbcL–psaI intergenic region, however, revealed a “hot-spot” of variation characterized by independent deletion events. The evolutionary implications of this observation are discussed. The complete plastome sequences are anticipated to provide the basis for potential organelle-specific genetic modification of pasture grasses. PMID:23550121

  9. Planktonic growth and biofilm formation profiles in Candida haemulonii species complex.

    Science.gov (United States)

    Ramos, Lívia S; Oliveira, Simone S C; Souto, Xênia M; Branquinha, Marta H; Santos, André L S

    2017-10-01

    Candida haemulonii species complex have emerged as multidrug-resistant yeasts able to cause fungemia worldwide. However, very little is known regarding their physiology and virulence factors. In this context, planktonic growth and biofilm formation of Brazilian clinical isolates of Candida haemulonii (n = 5), Candida duobushaemulonii (n = 4), and Candida haemulonii var. vulnera (n = 3) were reported. Overall, the fungal planktonic growth curves in Sabouraud dextrose broth reached the exponential phase in 48 h at 37°C. All the clinical isolates formed biofilm on polystyrene in a time-dependent event, as judged by the parameters evaluated: biomass (crystal violet staining), metabolic activity (XTT reduction), and extracellular matrix (safranin incorporation). No statistically significant differences were observed when the average measurements among the three Candida species were compared regarding both planktonic and biofilm lifestyles; however, typical isolate-specific differences were clearly noticed in fungal growth kinetics. © The Author 2017. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Mycobacterium ahvazicum sp. nov., the nineteenth species of the Mycobacterium simiae complex.

    Science.gov (United States)

    Bouam, Amar; Heidarieh, Parvin; Shahraki, Abodolrazagh Hashemi; Pourahmad, Fazel; Mirsaeidi, Mehdi; Hashemzadeh, Mohamad; Baptiste, Emeline; Armstrong, Nicholas; Levasseur, Anthony; Robert, Catherine; Drancourt, Michel

    2018-03-07

    Four slowly growing mycobacteria isolates were isolated from the respiratory tract and soft tissue biopsies collected in four unrelated patients in Iran. Conventional phenotypic tests indicated that these four isolates were identical to Mycobacterium lentiflavum while 16S rRNA gene sequencing yielded a unique sequence separated from that of M. lentiflavum. One representative strain AFP-003 T was characterized as comprising a 6,121,237-bp chromosome (66.24% guanosine-cytosine content) encoding for 5,758 protein-coding genes, 50 tRNA and one complete rRNA operon. A total of 2,876 proteins were found to be associated with the mobilome, including 195 phage proteins. A total of 1,235 proteins were found to be associated with virulence and 96 with toxin/antitoxin systems. The genome of AFP-003 T has the genetic potential to produce secondary metabolites, with 39 genes found to be associated with polyketide synthases and non-ribosomal peptide syntases and 11 genes encoding for bacteriocins. Two regions encoding putative prophages and three OriC regions separated by the dnaA gene were predicted. Strain AFP-003 T genome exhibits 86% average nucleotide identity with Mycobacterium genavense genome. Genetic and genomic data indicate that strain AFP-003 T is representative of a novel Mycobacterium species that we named Mycobacterium ahvazicum, the nineteenth species of the expanding Mycobacterium simiae complex.

  11. Alike but different: the evolution of the Tubifex tubifex species complex (Annelida, Clitellata) through polyploidization.

    Science.gov (United States)

    Marotta, Roberto; Crottini, Angelica; Raimondi, Elena; Fondello, Cristina; Ferraguti, Marco

    2014-04-02

    Tubifex tubifex is a widespread annelid characterized by considerable variability in its taxonomic characteristics and by a mixed reproductive strategy, with both parthenogenesis and biparental reproduction. In a molecular phylogenetic analysis, we detected substantial genetic variability among sympatric Tubifex spp. from the Lambro River (Milano, Italy), which we suggested comprise several cryptic species. To gain insights into the evolutionary events that generated this differentiation, we performed a cytogenetic analysis in parallel with a molecular assay. Approximately 80 cocoons of T. tubifex and T. blanchardi were collected and dissected. For each cocoon, we sequenced a fragment of the 16S rRNA from half of the sibling embryos and karyotyped the other half. To generate a robust phylogeny enabling the reconstruction of the evolutionary processes shaping the diversity of these sympatric lineages, we complemented our original 16S rRNA gene sequences with additional COI sequences. The chromosome number distribution was consistent with the presence of at least six sympatric euploid chromosome complements (one diploid, one triploid, three tetraploids and one hexaploid), as confirmed by a FISH assay performed with an homologous 18S rDNA probe. All the worms with 2n = 50 chromosomes belonged to an already identified sibling species of T. tubifex, T. blanchardi. The six euploid sets were coherently arranged in the phylogeny, with each lineage grouping specimens with the same chromosome complement. These results are compatible with the hypothesis that multiple polyploidization events, possibly enhanced by parthenogenesis, may have driven the evolution of the T. tubifex species complex.

  12. Evolutionary factors affecting Lactate dehydrogenase A and B variation in the Daphnia pulex species complex

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    Cristescu Melania E

    2011-07-01

    Full Text Available Abstract Background Evidence for historical, demographic and selective factors affecting enzyme evolution can be obtained by examining nucleotide sequence variation in candidate genes such as Lactate dehydrogenase (Ldh. Two closely related Daphnia species can be distinguished by their electrophoretic Ldh genotype and habitat. Daphnia pulex populations are fixed for the S allele and inhabit temporary ponds, while D. pulicaria populations are fixed for the F allele and inhabit large stratified lakes. One locus is detected in most allozyme surveys, but genome sequencing has revealed two genes, LdhA and LdhB. Results We sequenced both Ldh genes from 70 isolates of these two species from North America to determine if the association between Ldh genotype and habitat shows evidence for selection, and to elucidate the evolutionary history of the two genes. We found that alleles in the pond-dwelling D. pulex and in the lake-dwelling D. pulicaria form distinct groups at both loci, and the substitution of Glutamine (S for Glutamic acid (F at amino acid 229 likely causes the electrophoretic mobility shift in the LDHA protein. Nucleotide diversity in both Ldh genes is much lower in D. pulicaria than in D. pulex. Moreover, the lack of spatial structuring of the variation in both genes over a wide geographic area is consistent with a recent demographic expansion of lake populations. Neutrality tests indicate that both genes are under purifying selection, but the intensity is much stronger on LdhA. Conclusions Although lake-dwelling D. pulicaria hybridizes with the other lineages in the pulex species complex, it remains distinct ecologically and genetically. This ecological divergence, coupled with the intensity of purifying selection on LdhA and the strong association between its genotype and habitat, suggests that experimental studies would be useful to determine if variation in molecular function provides evidence that LDHA variants are adaptive.

  13. Lutzomyia umbratilis, the main vector of Leishmania guyanensis, represents a novel species complex?

    Science.gov (United States)

    Scarpassa, Vera Margarete; Alencar, Ronildo Baiatone

    2012-01-01

    Lutzomyia umbratilis is an important Leishmania guyanensis vector in South America. Previous studies have suggested differences in the vector competence between L. umbratilis populations situated on opposite banks of the Amazonas and Negro Rivers in the central Amazonian Brazil region, likely indicating a species complex. However, few studies have been performed on these populations and the taxonomic status of L. umbratilis remains unclear. Phylogeographic structure was estimated for six L. umbratilis samples from the central Amazonian region in Brazil by analyzing mtDNA using 1181 bp of the COI gene to assess whether the populations on opposite banks of these rivers consist of incipient or distinct species. The genetic diversity was fairly high and the results revealed two distinct clades ( = lineages) with 1% sequence divergence. Clade I consisted of four samples from the left bank of the Amazonas and Negro Rivers, whereas clade II comprised two samples from the right bank of Negro River. No haplotypes were shared between samples of two clades. Samples within clades exhibited low to moderate genetic differentiation (F(ST) = -0.0390-0.1841), whereas samples between clades exhibited very high differentiation (F(ST) = 0.7100-0.8497) and fixed differences. These lineages have diverged approximately 0.22 Mya in the middle Pleistocene. Demographic expansion was detected for the lineages I and II approximately 30,448 and 15,859 years ago, respectively, in the late Pleistocene. The two genetic lineages may represent an advanced speciation stage suggestive of incipient or distinct species within L. umbratilis. These findings suggest that the Amazonas and Negro Rivers may be acting as effective barriers, thus preventing gene flow between populations on opposite sides. Such findings have important implications for epidemiological studies, especially those related to vector competence and anthropophily, and for vector control strategies. In addition, L

  14. Fusarium Wilt Caused by Fusarium oxysporum on Passionfruit in Korea

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    Jae-Ho Joa

    2018-03-01

    Full Text Available From 2014 to 2016, Fusarium wilt disease was found on fassionfruit in Iksan and Jeju, Korea. Symptoms included wilting of foliage, drying and withering of leaves, and stunting of the plants. The infected plants eventually died during growth. Colonies on potato dextrose agar were pinkish white, and felted with cottony and aerial mycelia with 35 mm after one week. Macroconidia were falcate to almost straight, thin-walled and usually 2-3 septate. Microconidia were usually formed on monophialides of the hyphae and were hyaline, smooth, oval to ellipsoidal, aseptate or medianly 1-septate, very occasionally 2-septate, slightly constricted at the septa, 3-12 x 2.5-6 μm. On the basis of the morphological characteristics and phylogenetic analyses of two molecular markers, internal transcribed spacer rDNA and translation elongation factor 1α, the fungus was identified as Fusarium oxysporum. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch's postulates. To our knowledge, this is the first report on the occurrence of F. oxysporum on fassionfruit in Korea.

  15. Differential protein accumulations in isolates of the strawberry wilt pathogen Fusarium oxysporum f. sp. fragariae differing in virulence.

    Science.gov (United States)

    Fang, Xiangling; Barbetti, Martin J

    2014-08-28

    This study was conducted to define differences in Fusarium oxysporum f. sp. fragariae (Fof) isolates with different virulence efficiency to strawberry at the proteome level, in combination with their differences in mycelial growth, conidial production and germination. Comparative proteome analyses revealed substantial differences in mycelial proteomes between Fof isolates, where the 54 differentially accumulated protein spots were consistently over-accumulated or exclusively in the highly virulent isolate. These protein spots were identified through MALDI-TOF/TOF mass spectrometry analyses, and the identified proteins were mainly related to primary and protein metabolism, antioxidation, electron transport, cell cycle and transcription based on their putative functions. Proteins of great potential as Fof virulence factors were those involved in ubiquitin/proteasome-mediated protein degradation and reactive oxygen species detoxification; the hydrolysis-related protein haloacid dehalogenase superfamily hydrolase; 3,4-dihydroxy-2-butanone 4-phosphate synthase associated with riboflavin biosynthesis; and those exclusive to the highly virulent isolate. In addition, post-translational modifications may also make an important contribution to Fof virulence. F. oxysporum f. sp. fragariae (Fof), the causal agent of Fusarium wilt in strawberry, is a serious threat to commercial strawberry production worldwide. However, factors and mechanisms contributing to Fof virulence remained unknown. This study provides knowledge of the molecular basis for the differential expression of virulence in Fof, allowing new possibilities towards developing alternative and more effective strategies to manage Fusarium wilt. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Clean up fly ash from coal burning plants by new isolated fungi Fusarium oxysporum and Penicillium glabrum.

    Science.gov (United States)

    Ertit Taştan, Burcu

    2017-09-15

    In Turkey approximately 45 million tons of coals are burned in a year and 19.3 million tons of fly ash have emerged. The bioremediation of heavy metals or different elements from fly ash makes them bio-available. However, in previous studies, requiring of long operational time and failing to show tolerance to high pulp densities of fly ash of selected fungal species makes them impractical. In this work, bioremediation of fly ash by new isolated fungi Fusarium oxysporum and Penicillium glabrum were investigated in one step and two step bioremediation process. Ca, Si, Fe and S were found to be considerable amount in studied fly ashes by ED-XRF element analysis. The bioremediation yields of Mo (100%), S (64.36%) Ni (50%) and Cu (33.33%) by F. oxysporum were high. The remediated elements by P. glabrum in fly ash were Mo (100%), S (57.43%), Ni (25%), Si (24.66%), V (12.5%), Ti (5%) and Sr (3.2%). The isolation of high fly ash resistant fungi and reduction of the bioremediation time will allow the practical applications of the bioremediation technology when it is scaled up. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. The Mugil curema species complex (Pisces, Mugilidae): a new karyotype for the Pacific white mullet mitochondrial lineage.

    Science.gov (United States)

    Nirchio, Mauro; Oliveira, Claudio; Siccha-Ramirez, Zoila R; de Sene, Viviani F; Sola, Luciana; Milana, Valentina; Rossi, Anna Rita

    2017-01-01

    Recent molecular phylogenetic analyses have shown that the Mugil curema Valenciennes, 1836 species complex includes M. incilis Hancock, 1830, M. thoburni (Jordan & Starks, 1896) and at least four " M. curema " mitochondrial lineages, considered as cryptic species. The cytogenetic data on some representatives of the species complex have shown a high cytogenetic diversity. This research reports the results of cytogenetic and molecular analyses of white mullet collected in Ecuador. The analyzed specimens were molecularly assigned to the Mugil sp. O, the putative cryptic species present in the Pacific Ocean and showed a 2n = 46 karyotype, which is composed of 2 metacentric and 44 subtelocentric/acrocentric chromosomes. This karyotype is different from the one described for M. incilis (2n = 48) and from those of the two western Atlantic lineages Mugil curema (2n = 28), and Mugil margaritae (2n = 24). Data suggest the need for a morphological analysis to assign a species name to this Pacific lineage.

  18. The Mugil curema species complex (Pisces, Mugilidae: a new karyotype for the Pacific white mullet mitochondrial lineage

    Directory of Open Access Journals (Sweden)

    Mauro Nirchio

    2017-04-01

    Full Text Available Recent molecular phylogenetic analyses have shown that the Mugil curema Valenciennes, 1836 species complex includes M. incilis Hancock, 1830, M. thoburni (Jordan & Starks, 1896 and at least four “M. curema” mitochondrial lineages, considered as cryptic species. The cytogenetic data on some representatives of the species complex have shown a high cytogenetic diversity. This research reports the results of cytogenetic and molecular analyses of white mullet collected in Ecuador. The analyzed specimens were molecularly assigned to the Mugil sp. O, the putative cryptic species present in the Pacific Ocean and showed a 2n = 46 karyotype, which is composed of 2 metacentric and 44 subtelocentric/acrocentric chromosomes. This karyotype is different from the one described for M. incilis (2n = 48 and from those of the two western Atlantic lineages Mugil curema (2n = 28, and Mugil margaritae (2n = 24. Data suggest the need for a morphological analysis to assign a species name to this Pacific lineage.

  19. Evidence of diversity and recombination in Arsenophonus symbionts of the Bemisia tabaci species complex

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    Mouton Laurence

    2012-01-01

    Full Text Available Abstract Background Maternally inherited bacterial symbionts infecting arthropods have major implications on host ecology and evolution. Among them, the genus Arsenophonus is particularly characterized by a large host spectrum and a wide range of symbiotic relationships (from mutualism to parasitism, making it a good model to study the evolution of host-symbiont associations. However, few data are available on the diversity and distribution of Arsenophonus within host lineages. Here, we propose a survey on Arsenophonus diversity in whitefly species (Hemiptera, in particular the Bemisia tabaci species complex. This polyphagous insect pest is composed of genetic groups that differ in many ecological aspects. They harbor specific bacterial communities, among them several lineages of Arsenophonus, enabling a study of the evolutionary history of these bacteria at a fine host taxonomic level, in association to host geographical range and ecology. Results Among 152 individuals, our analysis identified 19 allelic profiles and 6 phylogenetic groups, demonstrating this bacterium's high diversity. These groups, based on Arsenophonus phylogeny, correlated with B. tabaci genetic groups with two exceptions reflecting horizontal transfers. None of three genes analyzed provided evidence of intragenic recombination, but intergenic recombination events were detected. A mutation inducing a STOP codon on one gene in a strain infecting one B. tabaci genetic group was also found. Phylogenetic analyses of the three concatenated loci revealed the existence of two clades of Arsenophonus. One, composed of strains found in other Hemiptera, could be the ancestral clade in whiteflies. The other, which regroups strains found in Hymenoptera and Diptera, may have been acquired more recently by whiteflies through lateral transfers. Conclusions This analysis of the genus Arsenophonus revealed a diversity within the B. tabaci species complex which resembles that reported on the

  20. Historical and current introgression in a Mesoamerican hummingbird species complex: a biogeographic perspective

    Directory of Open Access Journals (Sweden)

    Rosa Alicia Jiménez

    2016-01-01

    Full Text Available The influence of geologic and Pleistocene glacial cycles might result in morphological and genetic complex scenarios in the biota of the Mesoamerican region. We tested whether berylline, blue-tailed and steely-blue hummingbirds, Amazilia beryllina, Amazilia cyanura and Amazilia saucerottei, show evidence of historical or current introgression as their plumage colour variation might suggest. We also analysed the role of past and present climatic events in promoting genetic introgression and species diversification. We collected mitochondrial DNA (mtDNA sequence data and microsatellite loci scores for populations throughout the range of the three Amazilia species, as well as morphological and ecological data. Haplotype network, Bayesian phylogenetic and divergence time inference, historical demography, palaeodistribution modelling, and niche divergence tests were used to reconstruct the evolutionary history of this Amazilia species complex. An isolation-with-migration coalescent model and Bayesian assignment analysis were assessed to determine historical introgression and current genetic admixture. mtDNA haplotypes were geographically unstructured, with haplotypes from disparate areas interdispersed on a shallow tree and an unresolved haplotype network. Assignment analysis of the nuclear genome (nuDNA supported three genetic groups with signs of genetic admixture, corresponding to: (1 A. beryllina populations located west of the Isthmus of Tehuantepec; (2 A. cyanura populations between the Isthmus of Tehuantepec and the Nicaraguan Depression (Nuclear Central America; and (3 A. saucerottei populations southeast of the Nicaraguan Depression. Gene flow and divergence time estimates, and demographic and palaeodistribution patterns suggest an evolutionary history of introgression mediated by Quaternary climatic fluctuations. High levels of gene flow were indicated by mtDNA and asymmetrical isolation-with-migration, whereas the microsatellite analyses

  1. Historical and current introgression in a Mesoamerican hummingbird species complex: a biogeographic perspective

    Science.gov (United States)

    Jiménez, Rosa Alicia

    2016-01-01

    The influence of geologic and Pleistocene glacial cycles might result in morphological and genetic complex scenarios in the biota of the Mesoamerican region. We tested whether berylline, blue-tailed and steely-blue hummingbirds, Amazilia beryllina, Amazilia cyanura and Amazilia saucerottei, show evidence of historical or current introgression as their plumage colour variation might suggest. We also analysed the role of past and present climatic events in promoting genetic introgression and species diversification. We collected mitochondrial DNA (mtDNA) sequence data and microsatellite loci scores for populations throughout the range of the three Amazilia species, as well as morphological and ecological data. Haplotype network, Bayesian phylogenetic and divergence time inference, historical demography, palaeodistribution modelling, and niche divergence tests were used to reconstruct the evolutionary history of this Amazilia species complex. An isolation-with-migration coalescent model and Bayesian assignment analysis were assessed to determine historical introgression and current genetic admixture. mtDNA haplotypes were geographically unstructured, with haplotypes from disparate areas interdispersed on a shallow tree and an unresolved haplotype network. Assignment analysis of the nuclear genome (nuDNA) supported three genetic groups with signs of genetic admixture, corresponding to: (1) A. beryllina populations located west of the Isthmus of Tehuantepec; (2) A. cyanura populations between the Isthmus of Tehuantepec and the Nicaraguan Depression (Nuclear Central America); and (3) A. saucerottei populations southeast of the Nicaraguan Depression. Gene flow and divergence time estimates, and demographic and palaeodistribution patterns suggest an evolutionary history of introgression mediated by Quaternary climatic fluctuations. High levels of gene flow were indicated by mtDNA and asymmetrical isolation-with-migration, whereas the microsatellite analyses found evidence

  2. The purification and characterization of ATP synthase complexes from the mitochondria of four fungal species.

    Science.gov (United States)

    Liu, Sidong; Charlesworth, Thomas J; Bason, John V; Montgomery, Martin G; Harbour, Michael E; Fearnley, Ian M; Walker, John E

    2015-05-15

    The ATP synthases have been isolated by affinity chromatography from the mitochondria of the fungal species Yarrowia lipolytica, Pichia pastoris, Pichia angusta and Saccharomyces cerevisiae. The subunit compositions of the purified enzyme complexes depended on the detergent used to solubilize and purify the complex, and the presence or absence of exogenous phospholipids. All four enzymes purified in the presence of n-dodecyl-β-D-maltoside had a complete complement of core subunits involved directly in the synthesis of ATP, but they were deficient to different extents in their supernumerary membrane subunits. In contrast, the enzymes from P. angusta and S. cerevisiae purified in the presence of n-decyl-β-maltose neopentyl glycol and the phospholipids 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine, cardiolipin (diphosphatidylglycerol) and 1-palmitoyl-2-oleoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] had a complete complement of core subunits and also contained all of the known supernumerary membrane subunits, e, f, g, j, k and ATP8 (or Aap1), plus an additional new membrane component named subunit l, related in sequence to subunit k. The catalytic domain of the enzyme from P. angusta was more resistant to thermal denaturation than the enzyme from S. cerevisiae, but less stable than the catalytic domain of the bovine enzyme, but the stator and the integrity of the transmembrane proton pathway were most stable in the enzyme from P. angusta. The P. angusta enzyme provides a suitable source of enzyme for studying the structure of the membrane domain and properties associated with that sector of the enzyme complex.

  3. Taxonomic status of maskrays of the Neotrygon kuhlii species complex (Myliobatoidei: Dasyatidae) with the description of three new species from the Indo-West Pacific.

    Science.gov (United States)

    Last, Peter R; White, William T; Séret, Bernard

    2016-02-23

    The bluespotted maskray, Neotrygon kuhlii (Müller & Henle, 1841), once thought to be widely distributed in the Indo-West Pacific, consists of a complex of several species and the type series consists of multiple species; its nomenclature is discussed. A lectotype and paralectotype are designated and the species rediagnosed based on the types and a fresh specimen from Honiara (Solomon Islands), near to the collection locality of the lectotype (Vanikoro, Solomon Islands). Molecular and morphological data provide confirmatory evidence that this maskray is distinct from some other regional forms. Three members of the complex from the Western Pacific identified in earlier studies are confirmed to be new species; Neotrygon australiae sp. nov. (Australia, New Guinea and eastern Indonesia), N. caeruleopunctata sp. nov. (Indian Ocean), and N. orientale sp. nov. (North-West Pacific). These species differ from each other and N. kuhlii in their adult size, anterior angle of the disc, number and distribution of blue spots on the dorsal disc, and other more subtle morphometric and meristic characters. Another largely plain-coloured Neotrygon, also currently misidentified as N. kuhlii, is sympatric with N. orientale sp. nov. in the South China Sea and off Taiwan. Neotrygon varidens (Garman) is resurrected as the valid name for this ray. A key is provided to species of the genus.

  4. A comparison of the application of a biological and phenetic species concept in the Hebeloma crustuliniforme complex within a phylogenetic framework

    DEFF Research Database (Denmark)

    Aanen, Duur Kornelis; Kuyper, T.W.

    2004-01-01

    a major factor. Intercompatibility tests and DNA based phylogenies indicate that most biological species are very closely related and hence provide support for the claim that correspondence between a biological species concept and a phenetic species concept in the H. crustuliniforme complex is not likely...... biological species in that complex. Based on two nuclear sequences, we present a best estimate of the phylogeny of biological species within the complex. Using this phylogeny, on the basis of strict monophyly only two species can be morphologically recognised among 22 biological species. Relaxing......A method is presented to derive an operational phenetic species concept for the Hebeloma crustuliniforme complex in northwestern Europe. The complex was found to consist of at least 22 biological species (intercompatibility groups; ICGs). Almost none of these biological species could be recognised...

  5. Regulatory Mechanisms of a Highly Pectinolytic Mutant of Penicillium occitanis and Functional Analysis of a Candidate Gene in the Plant Pathogen Fusarium oxysporum

    Directory of Open Access Journals (Sweden)

    Gustavo Bravo-Ruiz

    2017-09-01

    Full Text Available Penicillium occitanis is a model system for enzymatic regulation. A mutant strain exhibiting constitutive overproduction of different pectinolytic enzymes both under inducing (pectin or repressing conditions (glucose was previously isolated after chemical mutagenesis. In order to identify the molecular basis of this regulatory mechanism, the genomes of the wild type and the derived mutant strain were sequenced and compared, providing the first reference genome for this species. We used a phylogenomic approach to compare P. occitanis with other pectinolytic fungi and to trace expansions of gene families involved in carbohydrate degradation. Genome comparison between wild type and mutant identified seven mutations associated with predicted proteins. The most likely candidate was a mutation in a highly conserved serine residue of a conserved fungal protein containing a GAL4-like Zn2Cys6 binuclear cluster DNA-binding domain and a fungus-specific transcription factor regulatory middle homology region. To functionally characterize the role of this candidate gene, the mutation was recapitulated in the predicted orthologue Fusarium oxysporum, a vascular wilt pathogen which secretes a wide array of plant cell wall degrading enzymes, including polygalacturonases, pectate lyases, xylanases and proteases, all of which contribute to infection. However, neither the null mutant nor a mutant carrying the analogous point mutation exhibited a deregulation of pectinolytic enzymes. The availability, annotation and phylogenomic analysis of the P. occitanis genome sequence represents an important resource for understanding the evolution and biology of this species, and sets the basis for the discovery of new genes of biotechnological interest for the degradation of complex polysaccharides.

  6. Species classifier choice is a key consideration when analysing low-complexity food microbiome data.

    Science.gov (United States)

    Walsh, Aaron M; Crispie, Fiona; O'Sullivan, Orla; Finnegan, Laura; Claesson, Marcus J; Cotter, Paul D

    2018-03-20

    The use of shotgun metagenomics to analyse low-complexity microbial communities in foods has the potential to be of considerable fundamental and applied value. However, there is currently no consensus with respect to choice of species classification tool, platform, or sequencing depth. Here, we benchmarked the performances of three high-throughput short-read sequencing platforms, the Illumina MiSeq, NextSeq 500, and Ion Proton, for shotgun metagenomics of food microbiota. Briefly, we sequenced six kefir DNA samples and a mock community DNA sample, the latter constructed by evenly mixing genomic DNA from 13 food-related bacterial species. A variety of bioinformatic tools were used to analyse the data generated, and the effects of sequencing depth on these analyses were tested by randomly subsampling reads. Compositional analysis results were consistent between the platforms at divergent sequencing depths. However, we observed pronounced differences in the predictions from species classification tools. Indeed, PERMANOVA indicated that there was no significant differences between the compositional results generated by the different sequencers (p = 0.693, R 2  = 0.011), but there was a significant difference between the results predicted by the species classifiers (p = 0.01, R 2  = 0.127). The relative abundances predicted by the classifiers, apart from MetaPhlAn2, were apparently biased by reference genome sizes. Additionally, we observed varying false-positive rates among the classifiers. MetaPhlAn2 had the lowest false-positive rate, whereas SLIMM had the greatest false-positive rate. Strain-level analysis results were also similar across platforms. Each platform correctly identified the strains present in the mock community, but accuracy was improved slightly with greater sequencing depth. Notably, PanPhlAn detected the dominant strains in each kefir sample above 500,000 reads per sample. Again, the outputs from functional profiling analysis using

  7. Characterization of a JAZ7 activation-tagged Arabidopsis mutant with increased susceptibility to the fungal pathogen Fusarium oxysporum

    Science.gov (United States)

    Thatcher, Louise F.; Cevik, Volkan; Grant, Murray; Zhai, Bing; Jones, Jonathan D.G.; Manners, John M.; Kazan, Kemal

    2016-01-01

    In Arabidopsis, jasmonate (JA)-signaling plays a key role in mediating Fusarium oxysporum disease outcome. However, the roles of JASMONATE ZIM-domain (JAZ) proteins that repress JA-signaling have not been characterized in host resistance or susceptibility to this pathogen. Here, we found most JAZ genes are induced following F. oxysporum challenge, and screening T-DNA insertion lines in Arabidopsis JAZ family members identified a highly disease-susceptible JAZ7 mutant (jaz7-1D). This mutant exhibited constitutive JAZ7 expression and conferred increased JA-sensitivity, suggesting activation of JA-signaling. Unlike jaz7 loss-of-function alleles, jaz7-1D also had enhanced JA-responsive gene expression, altered development and increased susceptibility to the bacterial pathogen Pst DC3000 that also disrupts host JA-responses. We also demonstrate that JAZ7 interacts with transcription factors functioning as activators (MYC3, MYC4) or repressors (JAM1) of JA-signaling and contains a functional EAR repressor motif mediating transcriptional repression via the co-repressor TOPLESS (TPL). We propose through direct TPL recruitment, in wild-type plants JAZ7 functions as a repressor within the JA-response network and that in jaz7-1D plants, misregulated ectopic JAZ7 expression hyper-activates JA-signaling in part by disturbing finely-tuned COI1-JAZ-TPL-TF complexes. PMID:26896849

  8. THE LESSONIA NIGRESCENS SPECIES COMPLEX (LAMINARIALES, PHAEOPHYCEAE) SHOWS STRICT PARAPATRY AND COMPLETE REPRODUCTIVE ISOLATION IN A SECONDARY CONTACT ZONE(1).

    Science.gov (United States)

    Tellier, Florence; Tapia, Javier; Faugeron, Sylvain; Destombe, Christophe; Valero, Myriam

    2011-08-01

    During secondary contact between phylogenetically closely related species (sibling species) having diverged in allopatry, the maintenance of species integrity depends on intrinsic and extrinsic reproductive barriers. In kelps (Phaeophyceae), the observations of hybrids in laboratory conditions suggest that reproductive isolation is incomplete. However, not all interspecific crosses are successful, and very few hybrids have been observed in nature, despite the co-occurrence of many kelp species in sympatry. This suggests that there are reproductive barriers that maintain species integrity. In this study, we characterized the fine genetic structure of a secondary contact zone to clarify the extent of reproductive isolation between two sister species. In Lessonia nigrescens Bory (Laminariales, Phaeophyta) species complex, two cryptic species have been recently found out from gene phylogenies, and-waiting for a formal taxonomic description-we used their geographic distribution to name them (northern and southern species). We studied 12 populations, distributed along 50 km of coastline, and employed two molecular approaches, assigning individuals to phylogenetic species according to a diagnostic mitochondrial marker (351 individuals analyzed) and quantifying interspecific gene flow with four microsatellite markers (248 individuals analyzed). No hybridization or introgression was revealed, indicating complete reproductive isolation in natural conditions. Unexpectedly, our study demonstrated that the two species were strictly segregated in space. This absence of co-occurrence along the contact zone can partially explain the lack of hybridization, raising new interesting questions as to the mechanisms that limit sympatry at small spatial scales. © 2011 Phycological Society of America.

  9. Cytogenetics of Physalis peruviana L. and Physalis floridana Rydb. genotypes with differential response to Fusarium oxysporum

    Directory of Open Access Journals (Sweden)

    Sara A. Liberato G.

    2014-01-01

    Full Text Available Vascular wilt caused by the fungus Fusarium oxysporumis considered the main constraint of cape gooseberry, Physalis peruviana, production in Colombia. P. peruvianaand P. floridana genotypes with differential resistance responses against F. oxysporum have been identified previously. In the present study, the genotypes were evaluated in order to complement the knowledge of cytogenetics diversity in Physalisand to design hybridization strategies to support breeding of cape gooseberry crop. The chromosome number in mitotic dividing cells from root-tips of tissue culture plantlets was determined, from which the average mitotic hour was estimated at 12:00 hours for P. peruviana and 10:00 for P. floridana. Chromosomic complements of 2n = 4x = 48 and 2n = 2x = 24 were found for each one of the two species. Additionally, flow cytometry analyses detected variation within P. peruviana with a nuclear DNA content of 2.33 pg for the 2n = 24 genotype and variations ranged from 5.77 to 8.12 pg for 2n = 48 genotypes. In P. floridanaDNA content was 2.29 pg in the 2n = 24 genotype and 4.03 pg in the 2n = 48 genotype. There was a significant effect (α = 0.01 of the number of chromosomes on nuclear DNA content for the two species.

  10. Selective whole genome amplification for resequencing target microbial species from complex natural samples.

    Science.gov (United States)

    Leichty, Aaron R; Brisson, Dustin

    2014-10-01

    Population genomic analyses have demonstrated power to address major questions in evolutionary and molecular microbiology. Collecting populations of genomes is hindered in many microbial species by the absence of a cost effective and practical method to collect ample quantities of sufficiently pure genomic DNA for next-generation sequencing. Here we present a simple method to amplify genomes of a target microbial species present in a complex, natural sample. The selective whole genome amplification (SWGA) technique amplifies target genomes using nucleotide sequence motifs that are common in the target microbe genome, but rare in the background genomes, to prime the highly processive phi29 polymerase. SWGA thus selectively amplifies the target genome from samples in which it originally represented a minor fraction of the total DNA. The post-SWGA samples are enriched in target genomic DNA, which are ideal for population resequencing. We demonstrate the efficacy of SWGA using both laboratory-prepared mixtures of cultured microbes as well as a natural host-microbe association. Targeted amplification of Borrelia burgdorferi mixed with Escherichia coli at genome ratios of 1:2000 resulted in >10(5)-fold amplification of the target genomes with genomic extracts from Wolbachia pipientis-infected Drosophila melanogaster resulted in up to 70% of high-throughput resequencing reads mapping to the W. pipientis genome. By contrast, 2-9% of sequencing reads were derived from W. pipientis without prior amplification. The SWGA technique results in high sequencing coverage at a fraction of the sequencing effort, thus allowing population genomic studies at affordable costs. Copyright © 2014 by the Genetics Society of America.

  11. Evidence for homoploid speciation in Phytophthora alni supports taxonomic reclassification in this species complex.

    Science.gov (United States)

    Husson, C; Aguayo, J; Revellin, C; Frey, P; Ioos, R; Marçais, B

    2015-04-01

    Alder decline has been a problem along European watercourses since the early 1990s. Hybridization was identified as the main cause of this emerging disease. Indeed, the causal agent, a soil-borne pathogen named Phytophthora alni subsp. alni (Paa) is the result of interspecific hybridization between two taxa, Phytophthora alni subsp. multiformis (Pam) and Phytophthora alni subsp. uniformis (Pau), initially identified as subspecies of Paa. The aim of this work was to characterize the ploidy level within the P. alni complex that is presently poorly understood. For that, we used two complementary approaches for a set of 31 isolates of Paa, Pam and Pau: (i) quantification of allele copy number of three single-copy nuclear genes using allele-specific real-time PCR and (ii) comparison of the genome size estimated by flow cytometry. Relative quantification of alleles of the three single-copy genes showed that the copy number of a given allele in Paa was systematically half that of its parents Pau or Pam. Moreover, DNA content estimated by flow cytometry in Paa was equal to half the sum of those in Pam and Pau. Our results therefore suggest that the hybrid Paa is an allotriploid species, containing half of the genome of each of its parents Pam and Pau, which in turn are considered to be allotetraploid and diploid, respectively. Paa thus results from a homoploid speciation process. Based on published data and on results from this study, a new formal taxonomic name is proposed for the three taxa Paa, Pam and Pau which are raised to species status and renamed P. ×alni, P. ×multiformis and P. uniformis, respectively. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Latitudinal variation of a defensive symbiosis in the Bugula neritina (Bryozoa sibling species complex.

    Directory of Open Access Journals (Sweden)

    Jonathan Linneman

    Full Text Available Mutualistic relationships are beneficial for both partners and are often studied within a single environment. However, when the range of the partners is large, geographical differences in selective pressure may shift the relationship outcome from positive to negative. The marine bryozoan Bugula neritina is a colonial invertebrate common in temperate waters worldwide. It is the source of bioactive polyketide metabolites, the bryostatins. Evidence suggests that an uncultured vertically transmitted symbiont, "Candidatus Endobugula sertula", hosted by B. neritina produces the bryostatins, which protect the vulnerable larvae from predation. Studies of B. neritina along the North American Atlantic coast revealed a complex of two morphologically similar sibling species separated by an apparent biogeographic barrier: the Type S sibling species was found below Cape Hatteras, North Carolina, while Type N was found above. Interestingly, the Type N colonies lack "Ca. Endobugula sertula" and, subsequently, defensive bryostatins; their documented northern distribution was consistent with traditional biogeographical paradigms of latitudinal variation in predation pressure. Upon further sampling of B. neritina populations, we found that both host types occur in wider distribution, with Type N colonies living south of Cape Hatteras, and Type S to the north. Distribution of the symbiont, however, was not restricted to Type S hosts. Genetic and microscopic evidence demonstrates the presence of the symbiont in some Type N colonies, and larvae from these colonies are endowed with defensive bryostatins and contain "Ca. Endobugula sertula". Molecular analysis of the symbiont from Type N colonies suggests an evolutionarily recent acquisition, which is remarkable for a symbiont thought to be transmitted only vertically. Furthermore, most Type S colonies found at higher latitudes lack the symbiont, suggesting that this host-symbiont relationship is more flexible than

  13. Contrasting Patterns of rDNA Homogenization within the Zygosaccharomyces rouxii Species Complex

    Science.gov (United States)

    Chand Dakal, Tikam; Giudici, Paolo; Solieri, Lisa

    2016-01-01

    Arrays of repetitive ribosomal DNA (rDNA) sequences are generally expected to evolve as a coherent family, where repeats within such a family are more similar to each other than to orthologs in related species. The continuous homogenization of repeats within individual genomes is a recombination process termed concerted evolution. Here, we investigated the extent and the direction of concerted evolution in 43 yeast strains of the Zygosaccharomyces rouxii species complex (Z. rouxii, Z. sapae, Z. mellis), by analyzing two portions of the 35S rDNA cistron, namely the D1/D2 domains at the 5’ end of the 26S rRNA gene and the segment including the internal transcribed spacers (ITS) 1 and 2 (ITS regions). We demonstrate that intra-genomic rDNA sequence variation is unusually frequent in this clade and that rDNA arrays in single genomes consist of an intermixing of Z. rouxii, Z. sapae and Z. mellis-like sequences, putatively evolved by reticulate evolutionary events that involved repeated hybridization between lineages. The levels and distribution of sequence polymorphisms vary across rDNA repeats in different individuals, reflecting four patterns of rDNA evolution: I) rDNA repeats that are homogeneous within a genome but are chimeras derived from two parental lineages via recombination: Z. rouxii in the ITS region and Z. sapae in the D1/D2 region; II) intra-genomic rDNA repeats that retain polymorphisms only in ITS regions; III) rDNA repeats that vary only in their D1/D2 domains; IV) heterogeneous rDNA arrays that have both polymorphic ITS and D1/D2 regions. We argue that an ongoing process of homogenization following allodiplodization or incomplete lineage sorting gave rise to divergent evolutionary trajectories in different strains, depending upon temporal, structural and functional constraints. We discuss the consequences of these findings for Zygosaccharomyces species delineation and, more in general, for yeast barcoding. PMID:27501051

  14. Ligninolytic enzymes in the coal solubilizing deuteromycetes Trichoderma atroviride and Fusarium oxysporum

    Energy Technology Data Exchange (ETDEWEB)

    Moenkemann, H.; Scheel, T.; Hoelker, U.; Ludwig, S.; Hoefer, M. [Bonn Univ. (Germany). Botanisches Inst.

    1997-12-31

    Evidence is presented for the lignite induced expression of lignin peroxidases, manganese-dependent peroxidases, laccases and glyoxal oxidases in the coal solubilizing fungi Trichoderma atroviride and Fusarium oxysporum under different growth conditions. (orig.)

  15. Fusarium verwelkingsziekte in tomaat geen probleem meer dankzij resistentie: Speciale vormen Fusarium oxysporum veroorzaken ziekten

    NARCIS (Netherlands)

    Paternotte, S.J.

    2011-01-01

    Fusarium oxysporum is een algemeen voorkomende bodemschimmel. Speciale vormen kunnen problemen veroorzaken zoals verwelkingsziekte en voet- en wortelrot in verschillende vruchtgroentegewassen, potplanten en snijbloemen en zuur in bolgewassen. Per gewas kan de schade variëren van minimaal, doordat

  16. Identification of RNA species in the RNA-toxin complex and structure of the complex in Clostridium botulinum type E.

    Science.gov (United States)

    Kitamura, Masaru

    2002-02-15

    Clostridium botulinum type E toxin was isolated in the form of a complex with RNA(s) from bacterial cells. Characterization of the complexed RNA remains to be elucidated. The RNA is identified here as ribosomal RNA (rRNA) having 23S and 16S components. The RNA-toxin complexes were found to be made up of three types with different molecular sizes. The three types of RNA-toxin complex are toxin bound to both the 23S and 16S rRNA, toxin bound to the 16S rRNA and a small amount of 23S rRNA, and toxin bound only to the 16S rRNA. ©2002 Elsevier Science (USA).

  17. Universal Plant DNA Barcode Loci May Not Work in Complex Groups: A Case Study with Indian Berberis Species

    Science.gov (United States)

    Roy, Sribash; Tyagi, Antariksh; Shukla, Virendra; Kumar, Anil; Singh, Uma M.; Chaudhary, Lal Babu; Datt, Bhaskar; Bag, Sumit K.; Singh, Pradhyumna K.; Nair, Narayanan K.; Husain, Tariq; Tuli, Rakesh

    2010-01-01

    Background The concept of DNA barcoding for species identification has gained considerable momentum in animals because of fairly successful species identification using cytochrome oxidase I (COI). In plants, matK and rbcL have been proposed as standard barcodes. However, barcoding in complex genera is a challenging task. Methodology and Principal Findings We investigated the species discriminatory power of four reportedly most promising plant DNA barcoding loci (one from nuclear genome- ITS, and three from plastid genome- trnH-psbA, rbcL and matK) in species of Indian Berberis L. (Berberidaceae) and two other genera, Ficus L. (Moraceae) and Gossypium L. (Malvaceae). Berberis species were delineated using morphological characters. These characters resulted in a well resolved species tree. Applying both nucleotide distance and nucleotide character-based approaches, we found that none of the loci, either singly or in combinations, could discriminate the species of Berberis. ITS resolved all the tested species of Ficus and Gossypium and trnH-psbA resolved 82% of the tested species in Ficus. The highly regarded matK and rbcL could not resolve all the species. Finally, we employed amplified fragment length polymorphism test in species of Berberis to determine their relationships. Using ten primer pair combinations in AFLP, the data demonstrated incomplete species resolution. Further, AFLP analysis showed that there was a tendency of the Berberis accessions to cluster according to their geographic origin rather than species affiliation. Conclusions/Significance We reconfirm the earlier reports that the concept of universal barcode in plants may not work in a number of genera. Our results also suggest that the matK and rbcL, recommended as universal barcode loci for plants, may not work in all the genera of land plants. Morphological, geographical and molecular data analyses of Indian species of Berberis suggest probable reticulate evolution and thus barcode markers may

  18. Universal plant DNA barcode loci may not work in complex groups: a case study with Indian berberis species.

    Directory of Open Access Journals (Sweden)

    Sribash Roy

    Full Text Available BACKGROUND: The concept of DNA barcoding for species identification has gained considerable momentum in animals because of fairly successful species identification using cytochrome oxidase I (COI. In plants, matK and rbcL have been proposed as standard barcodes. However, barcoding in complex genera is a challenging task. METHODOLOGY AND PRINCIPAL FINDINGS: We investigated the species discriminatory power of four reportedly most promising plant DNA barcoding loci (one from nuclear genome--ITS, and three from plastid genome--trnH-psbA, rbcL and matK in species of Indian Berberis L. (Berberidaceae and two other genera, Ficus L. (Moraceae and Gossypium L. (Malvaceae. Berberis species were delineated using morphological characters. These characters resulted in a well resolved species tree. Applying both nucleotide distance and nucleotide character-based approaches, we found that none of the loci, either singly or in combinations, could discriminate the species of Berberis. ITS resolved all the tested species of Ficus and Gossypium and trnH-psbA resolved 82% of the tested species in Ficus. The highly regarded matK and rbcL could not resolve all the species. Finally, we employed amplified fragment length polymorphism test in species of Berberis to determine their relationships. Using ten primer pair combinations in AFLP, the data demonstrated incomplete species resolution. Further, AFLP analysis showed that there was a tendency of the Berberis accessions to cluster according to their geographic origin rather than species affiliation. CONCLUSIONS/SIGNIFICANCE: We reconfirm the earlier reports that the concept of universal barcode in plants may not work in a number of genera. Our results also suggest that the matK and rbcL, recommended as universal barcode loci for plants, may not work in all the genera of land plants. Morphological, geographical and molecular data analyses of Indian species of Berberis suggest probable reticulate evolution and thus

  19. Otolith shape analysis and mitochondrial DNA markers distinguish three sand smelt species in the Atherina boyeri species complex in western Mediterranean

    Science.gov (United States)

    Boudinar, A. S.; Chaoui, L.; Quignard, J. P.; Aurelle, D.; Kara, M. H.

    2016-12-01

    Atherina boyeri is a common euryhaline teleost fish in the Mediterranean and adjacent areas, which inhabits coastal and estuarine waters, including coastal lagoons and more rarely inland waters. Several recent studies have pointed the possible existence of three distinct groups or species, one lagoon/freshwater group and two 'punctuated and unpunctuated on the flanks' marine groups, within an A. boyeri species complex. This study is a combined approach using otolith shape and molecular markers to better define the structure of the species in the western Mediterranean. Genetic differentiation and species delimitation among nine Atherina boyeri populations from several marine and lagoon/brakish habitat sites in Algeria, Tunisia and France were investigated using three mitochondrial (control region, Cyt b and 16S) and one nuclear markers (2nd intron of S7). For further phylogenetic and phylogeographic study, we added sequences from Genbank covering more areas (Ionian Sea, Adriatic Sea, Tyrrhenian Sea, Black Sea, Atlantic). Five groups were found. Two of them perfectly corresponded to two species already recognized Atherina presbyter and Atherina hepsetus, both living in marine waters; and three additional, including Atherina boyeri (brackish and freshwater environments) and two independent groups of marine punctated and unpunctated individuals. Those findings are corroborated by the study of the otolith contour shape of 362 individuals of seven populations from different habitats using Fourier analysis. Individuals could be discriminated into five groups based on the first two functions (Wilk's lambda = 0.07, p < 0.001). Samples from Ziama inlet, marine punctuated individuals and unpunctuated marine specimens from Annaba's Gulf formed three well separated groups. Specimens from Mellah and Mauguio lagoons formed another group. The last one includes individuals from Bizerte and Thau lagoons. The divergences between them strongly support the potential species within the

  20. A Molecular Phylogeny of Anopheles Annulipes (Diptera: Culicidae) sensu lato: The Most Species-Rich Anopheline Complex

    Science.gov (United States)

    2006-09-27

    Maximum parsimony; Sibling species; Species complex; Myxomatosis ; DNA barcoding; Australia; Papua New Guinea; ITS2; COI; COII; EF-11. Introduction... myxomatosis to con- trol rabbits (Fenner and RatcliVe, 1965). Chris Green used data from cross-matings and the band- ing pattern of polytene chromosomes to... myxomatosis based on distribution but more sam- pling is required to conWrm this. Many of the sampling locations in this study and the allozyme study of

  1. Sensitivity of some nitrogen fixers and the target pest Fusarium oxysporum to fungicide thiram

    OpenAIRE

    Osman, Awad G.; Sherif, Ashraf M.; Elhussein, Adil A.; Mohamed, Afrah T.

    2012-01-01

    This study was carried out to investigate the toxic effects of the fungicide thiram (TMTD) against five nitrogen fixers and the thiram target pest Fusarium oxysporum under laboratory conditions. Nitrogen fixing bacteria Falvobacterium showed the highest values of LD50 and proved to be the most resistant to the fungicide followed by Fusarium oxysporum, while Pseudomonas aurentiaca was the most affected microorganism. LD50 values for these microorganisms were in 2–5 orders of magnitude lower in...

  2. DNA-fingerprinting (AFLP and RFLP) for genotypic identification in species of the Pleurotus eryngii complex.

    Science.gov (United States)

    Urbanelli, S; Della Rosa, V; Punelli, F; Porretta, D; Reverberi, M; Fabbri, A A; Fanelli, C

    2007-03-01

    Wild populations of edible species are important source of genetic variability for cultivated lines that can undergo a drastic loss of diversity resulting from man's selection. The development of tools aimed at the clear-cut and safe identification and assessment of genetic variability of the wild and cultivated strains is thus a fundamental goal of molecular genetic research. In this study, we used two polymerase chain reaction (PCR)-based fingerprinting methods-amplified fragment length polymorphism (AFLP) and restriction fragment length polymorphism (RFLP) of laccase and manganese peroxidase genes-to assess genetic differences among strains and independently evolving lineages belonging to the Pleurotus eryngii complex. Both laccase RFLP and AFLP have been proved to distinguish unambiguously the three taxa studied: Pleurotus ferulae, P. eryngii, and P. eryngii var. nebrodensis. AFLP also showed enough sensitivity to detect polymorphisms among the strains, proving to be an efficient DNA fingerprinting tool in studies of strain assignment. The divergent RFLP laccase and manganese peroxidase patterns are also discussed in relation to the role played by these genes in the interaction between these fungi and their host plants.

  3. Predictors for reproductive isolation in a ring species complex following genetic and ecological divergence.

    Science.gov (United States)

    Pereira, Ricardo J; Monahan, William B; Wake, David B

    2011-07-06

    Reproductive isolation (RI) is widely accepted as an important "check point" in the diversification process, since it defines irreversible evolutionary trajectories. Much less consensus exists about the processes that might drive RI. Here, we employ a formal quantitative analysis of genetic interactions at several stages of divergence within the ring species complex Ensatina eschscholtzii in order to assess the relative contribution of genetic and ecological divergence for the development of RI. By augmenting previous genetic datasets and adding new ecological data, we quantify levels of genetic and ecological divergence between populations and test how they correlate with a restriction of genetic admixture upon secondary contact. Our results indicate that the isolated effect of ecological divergence between parental populations does not result in reproductively isolated taxa, even when genetic transitions between parental taxa are narrow. Instead, processes associated with overall genetic divergence are the best predictors of reproductive isolation, and when parental taxa diverge in nuclear markers we observe a complete cessation of hybridization, even to sympatric occurrence of distinct evolutionary lineages. Although every parental population has diverged in mitochondrial DNA, its degree of divergence does not predict the extent of RI. These results show that in Ensatina, the evolutionary outcomes of ecological divergence differ from those of genetic divergence. While evident properties of taxa may emerge via ecological divergence, such as adaptation to local environment, RI is likely to be a byproduct of processes that contribute to overall genetic divergence, such as time in geographic isolation, rather than being a direct outcome of local adaptation.

  4. A revision of the history of the Colletotrichum acutatum species complex in the Nordic countries based on herbarium specimens.

    Science.gov (United States)

    Sundelin, Thomas; Strømeng, Gunn Mari; Gjærum, Halvor B; Amby, Daniel Buchvaldt; Ørstad, Kari; Jensen, Birgit; Lund, Ole Søgaard; Stensvand, Arne

    2015-08-01

    Herbaria collections containing plants with disease symptoms are highly valuable, and they are often the only way to investigate outbreaks and epidemics from the past as the number of viable isolates in culture collections is often limited. Species belonging to the Colletotrichum acutatum complex infect a range of important crops. As members of the C. acutatum complex are easily confused with other Colletotrichum species, molecular methods are central for the correct identification. We performed molecular analyses on 21 herbaria specimens, displaying anthracnose symptoms, collected in Norway and Denmark before the first confirmed findings of C. acutatum complex members in this region. Sequencing parts of the fungal ITS regions showed that members of the species complex were present in 13 of the 21 specimens collected in different parts of Norway and Denmark between 1948 and 1991, representing seven plant hosts (three cherry species, apple, raspberry and rhododendron). This is the first time herbarium specimens have been used to study these pathogens under Nordic conditions. Differences in the ITS sequences suggest the presence of different genotypes within the complex, indicating a well-established population. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Studies on fluctuating asymmetry (FA for certain morphological traits in four species of the Drosophila bipectinata complex

    Directory of Open Access Journals (Sweden)

    Banerjee Parul

    2015-01-01

    Full Text Available Fluctuating asymmetry (FA is defined as subtle deviations from perfect bilateral symmetry, evident in differences between the right and the left sides of any given trait. It is a pattern of variation between sides and measures developmental instability. Differences in the level of FA may be used for comparing developmental precision among closely related species and thus may give an idea whether developmental stability was affected during the divergence and separation of populations into distinct species. Keeping this in view, FA was studied in four species of the Drosophila bipectinata complex i.e. D. bipectinata, D. parabipectinata, D. malerkotliana and D. pseudoananassae. In females of all the four species, FA values did not vary significantly for any of the traits considered. However, in case of males, they varied significantly for Wing length (WL and sex comb tooth number (SCTN. Also, while in females Composite fluctuating asymmetry (CFA did not exhibit significant variation, in males it was found to vary significantly across the four species. However, Bonferroni t-tests did not reveal any consistent difference in FA levels between any two species. The magnitude of FA was found to differ significantly among traits and CFA values were found to be higher for males than females in all the four species. Therefore, it may be concluded that the level of FA shows trait specific variations and males are more prone to developmental perturbations. However, the FA levels are more or less similar in all the four species of this complex. Thus, developmental precision remains nearly same in all the four species of this complex irrespective of the degree of evolutionary divergence reached.

  6. Formulation of the endophytic fungus Cladosporium oxysporum Berk.

    Directory of Open Access Journals (Sweden)

    Bensaci Oussama Ali

    2015-01-01

    Full Text Available Two formulations containing culture filtrates and conidial suspensions of the endophytic fungus Cladosporium oxysporum Berk. & M.A. Curtis, isolated previously from stems of Euphorbia bupleuroides subsp. luteola (Kralik Maire, were experimentally tested for their aphicid activity against the black bean aphid Aphis fabae Scop. found in Algeria. It was shown that invert emulsions are more effective against aphids, than using aqueous suspensions. This was especially true for formulations containing culture filtrates. The relatively insignificant mortalities obtained by formulations containing conidial suspensions indicated a low infectious potential towards the aphids. The proteolytic activity seemed to be more important than the chitinolytic activity of the fungus against the black bean aphid A. fabae

  7. Systematics of treefrogs of the Hypsiboas calcaratus and Hypsiboas fasciatus species complex (Anura, Hylidae with the description of four new species

    Directory of Open Access Journals (Sweden)

    Marcel Caminer

    2014-01-01

    Full Text Available We review the systematics of the Hypsiboas calcaratus species complex, a group of widely distributed Amazonian hylid frogs. A comprehensive analysis of genetic, morphological, and bioacoustic datasets uncovered the existence of eleven candidate species, six of which are confirmed. Two of them correspond to Hypsiboas fasciatus and Hypsiboas calcaratus and the remaining four are new species that we describe here. Hypsiboas fasciatus sensu stricto has a geographic range restricted to the eastern Andean foothills of southern Ecuador while Hypsiboas calcaratus sensu stricto has a wide distribution in the Amazon basin. Hypsiboas almendarizae sp. n. occurs at elevations between 500 and 1950 m in central and northern Ecuador; the other new species (H. maculateralis sp. n., H. alfaroi sp. n., and H. tetete sp. n. occur at elevations below 500 m in Amazonian Ecuador and Peru. The new species differ from H. calcaratus and H. fasciatus in morphology, advertisement calls, and mitochondrial and nuclear DNA sequences. Five candidate species from the Guianan region, Peru, and Bolivia are left as unconfirmed. Examination of the type material of Hyla steinbachi, from Bolivia, shows that it is not conspecific with H. fasciatus and thus is removed from its synonymy.

  8. Sensitivity of some nitrogen fixers and the target pest Fusarium oxysporum to fungicide thiram.

    Science.gov (United States)

    Osman, Awad G; Sherif, Ashraf M; Elhussein, Adil A; Mohamed, Afrah T

    2012-03-01

    This study was carried out to investigate the toxic effects of the fungicide thiram (TMTD) against five nitrogen fixers and the thiram target pest Fusarium oxysporum under laboratory conditions. Nitrogen fixing bacteria Falvobacterium showed the highest values of LD(50) and proved to be the most resistant to the fungicide followed by Fusarium oxysporum, while Pseudomonas aurentiaca was the most affected microorganism. LD(50) values for these microorganisms were in 2-5 orders of magnitude lower in comparison with LD(50) value for Fusarium oxysporum. Thiram was most toxic to Pseudomonas aurentiaca followed by Azospirillum. The lowest toxicity index was recorded for Fusarium oxysporum and Flavobacterium. The slope of the curve for Azomonas, Fusarium oxysporum and Flavobacterium is more steep than that of the other curves, suggesting that even a slight increase of the dose of the fungicide can cause a very strong negative effect. Thiram was more selective to Pseudomonas aurentiaca followed by Azospirillum, Rhizobium meliloti and Azomonas. The lowest selectivity index of the fungicide was recorded for Falvobacterium followed by Fusarium oxysporum. The highest safety coefficient of the fungicide was assigned for Flavobacterium, while Pseudomonas aurentiaca showed the lowest value.

  9. Bioacoustic investigations and taxonomic considerations on the Cicadetta montana species complex (Homoptera: Cicadoidea: Tibicinidae

    Directory of Open Access Journals (Sweden)

    Matija Gogala

    2004-06-01

    Full Text Available Recent bioacoustic investigations have shown that Cicadetta montana Scopoli 1772 is a complex of morphologically similar sister species that are best characterized by their song patterns. At the type locality of C. montana, only mountain cicadas with simple, long lasting song phrases were heard, recorded and collected. Therefore, we have good reasons to suggest that this type of song is characteristic for C. montana s. str. Boulard described a song of C. montana from France with phrases composed of a long and a short echeme; this type of song is characteristic for cicadas morphologically corresponding to C. montana var. brevipennis Fieber 1876; we suggest to raise this taxon to species level. On the basis of specific song, Puissant and Boulard described C. cerdaniensis from Pyrénées. A similar case was the discovery and description of C. montana macedonica Schedl 1999 from Macedonia; since these Macedonian cicadas are sympatric with at least two other cryptic species in the C. montana group and molecular investigations showed substantial genetic differences between C. macedonica and C. montana or C. brevipennis, we conclude that this taxon should also be raised to species level. Songs of closely related C. podolica and Korean mountain cicada are presented as well.Pesquisas recentes de bioacústica mostraram que Cicadetta montana Scopoli 1772 é um complexo de espécie-irmãs morfologicamente semelhantes e melhor caracterizadas por seus padrões de canto. Na localidade-tipo de C. montana somente cigarras serranas de longas frases de canto foram ouvidas, gravadas e coletadas. Portanto, temos boas razões para propor este tipo de canto como característico de C. montana s. str. Boulard descreveu um canto de C. montana da França com frases compostas de uma estridulação longa e uma curta; este tipo de canto é característico das cigarras correspondendo morfologicamente a C. montana var. brevipennis Fieber 1876; sugerimos elevar este táxon ao n

  10. Disparity in population differentiation of sex-linked and autosomal variation in sibling species of the Jaera albifrons (Isopoda) complex

    DEFF Research Database (Denmark)

    Siegismund, H R

    2003-01-01

    The genetic variation at four enzyme loci is described for 22 populations of three Jaera species--J. albifrons, J. ischiosetosa, and J. praehirsuta--in the J. albifrons complex (Crustacea, Isopoda) in Denmark. The variation at three of the loci is similar, with the allele frequency spectra close...... to each other in all three species. An evolutionary tree based on the variation at these three loci revealed that the populations from the different species are completely intermixed in the tree. This was supported by hierarchical F-statistics where the between-species component was zero. At a fourth....... An evolutionary tree for this locus partitions the populations into separate groups and a hierarchical F-statistic has a between-species component of about 50%. The results are attributed to introgression with a higher rate for autosomes than for sex chromosomes....

  11. Identifikasi Ras Fisiologis Fusarium Oxysporum F.sp. Cubense Berdasarkan Sifat Kompatibel secara Vegetatif dan Pembentukan Bahan Volatil

    OpenAIRE

    Wibowo, Arif; Suryanti, Suryanti; Sumardiyono, Christanti

    2002-01-01

    Race characterization of F. oxysporum Schlecht. f.sp. cubense (E.F. Smith) Snyd. & Hans. by determining disease reaction is difficult because the result may be biased due to the variability of growing condition. This study is aimed to identify physiological races of F. oxysporum f.sp. cubense in banana plantation in the province of Daerah Istimewa Yogyakarta by examining the relation of the fungal pathogen isolates. The identification of physiological races of F. oxysporum f.sp. cubense was b...

  12. Formal Revision of the Alexandrium tamarense Species Complex (Dinophyceae) Taxonomy: The Introduction of Five Species with Emphasis on Molecular-based (rDNA) Classification

    Science.gov (United States)

    John, Uwe; Litaker, R. Wayne; Montresor, Marina; Murray, Shauna; Brosnahan, Michael L.; Anderson, Donald M.

    2015-01-01

    The Alexandrium tamarense species complex is one of the most studied marine dinoflagellate groups due to its ecological, toxicological and economic importance. Several members of this complex produce saxitoxin and its congeners – potent neurotoxins that cause paralytic shellfish poisoning. Isolates from this complex are assigned to A. tamarense, A. fundyense, or A. catenella based on two main morphological characters: the ability to form chains and the presence/absence of a ventral pore between Plates 1′ and 4′. However, studies have shown that these characters are not consistent and/or distinctive. Further, phylogenies based on multiple regions in the rDNA operon indicate that the sequences from morphologically indistinguishable isolates partition into five clades. These clades were initially named based on their presumed geographic distribution, but recently were renamed as Groups I–V following the discovery of sympatry among some groups. In this study we present data on morphology, ITS/5.8S genetic distances, ITS2 compensatory base changes, mating incompatibilities, toxicity, the sxtA toxin synthesis gene, and rDNA phylogenies. All results were consistent with each group representing a distinct cryptic species. Accordingly, the groups were assigned species names as follows: Group I, A. fundyense; Group II, A. mediterraneum; Group III, A. tamarense; Group IV, A. pacificum; Group V, A. australiense. PMID:25460230

  13. Estimation of isolation times of the island species in the Drosophila simulans complex from multilocus DNA sequence data.

    Directory of Open Access Journals (Sweden)

    Shannon R McDermott

    2008-06-01

    Full Text Available The Drosophila simulans species complex continues to serve as an important model system for the study of new species formation. The complex is comprised of the cosmopolitan species, D. simulans, and two island endemics, D. mauritiana and D. sechellia. A substantial amount of effort has gone into reconstructing the natural history of the complex, in part to infer the context in which functional divergence among the species has arisen. In this regard, a key parameter to be estimated is the initial isolation time (t of each island species. Loci in regions of low recombination have lower divergence within the complex than do other loci, yet divergence from D. melanogaster is similar for both classes. This might reflect gene flow of the low-recombination loci subsequent to initial isolation, but it might also reflect differential effects of changing population size on the two recombination classes of loci when the low-recombination loci are subject to genetic hitchhiking or pseudohitchhikingNew DNA sequence variation data for 17 loci corroborate the prior observation from 13 loci that DNA sequence divergence is reduced in genes of low recombination. Two models are presented to estimate t and other relevant parameters (substitution rate correction factors in lineages leading to the island species and, in the case of the 4-parameter model, the ratio of ancestral to extant effective population size from the multilocus DNA sequence data.In general, it appears that both island species were isolated at about the same time, here estimated at approximately 250,000 years ago. It also appears that the difference in divergence patterns of genes in regions of low and higher recombination can be reconciled by allowing a modestly larger effective population size for the ancestral population than for extant D. simulans.

  14. Conservation and Divergence in the Candida Species Biofilm Matrix Mannan-Glucan Complex Structure, Function, and Genetic Control.

    Science.gov (United States)

    Dominguez, Eddie; Zarnowski, Robert; Sanchez, Hiram; Covelli, Antonio S; Westler, William M; Azadi, Parastoo; Nett, Jeniel; Mitchell, Aaron P; Andes, David R

    2018-04-03

    Candida biofilms resist the effects of available antifungal therapies. Prior studies with Candida albicans biofilms show that an extracellular matrix mannan-glucan complex (MGCx) contributes to antifungal sequestration, leading to drug resistance. Here we implement biochemical, pharmacological, and genetic approaches to explore a similar mechanism of resistance for the three most common clinically encountered non- albicans Candida species (NAC). Our findings reveal that each Candida species biofilm synthesizes a mannan-glucan complex and that the antifungal-protective function of this complex is conserved. Structural similarities extended primarily to the polysaccharide backbone (α-1,6-mannan and β-1,6-glucan). Surprisingly, biochemical analysis uncovered stark differences in the branching side chains of the MGCx among the species. Consistent with the structural analysis, similarities in the genetic control of MGCx production for each Candida species also appeared limited to the synthesis of the polysaccharide backbone. Each species appears to employ a unique subset of modification enzymes for MGCx synthesis, likely accounting for the observed side chain diversity. Our results argue for the conservation of matrix function among Candida spp. While biogenesis is preserved at the level of the mannan-glucan complex backbone, divergence emerges for construction of branching side chains. Thus, the MGCx backbone represents an ideal drug target for effective pan- Candida species biofilm therapy. IMPORTANCE Candida species, the most common fungal pathogens, frequently grow as a biofilm. These adherent communities tolerate extremely high concentrations of antifungal agents, due in large part, to a protective extracellular matrix. The present studies define the structural, functional, and genetic similarities and differences in the biofilm matrix from the four most common Candida species. Each species synthesizes an extracellular mannan-glucan complex (MGCx) which

  15. Estudio del antagonismo de algunas especies de Trichoderma sobre Fusarium Oxysporum y Rhizoctonia Solani Antagonism studies of Trichoderma sp.p.. with Fusarium oxysporum and Rhizoctonia solani

    OpenAIRE

    Elias Ricardo; Arcos Omar; Arbelaez Germán

    1989-01-01

    En este trabajo se estudió el antagonismo de algunos aislamientos del hongo Trichoderma obtenidos de suelos colornbianos en el control de Fusarium oxysporum y Rhizoctonia solani. En los ensayos "in vitre" se observó un marcado antagonismo entre las colonias de los aislamientos de Trichoderma sobre R. sotsni, con una reducción apreciable
    del tamaño de la colonia y un antaqonismo menor sobre F. oxysporum. En los ensayos de parasitismo a nivel microscópico, se observó una gran interac...

  16. Limnephilid taxa revised by speciation traits: Rhadicoleptus, Isogamus, Melampophylax genera, Chaetopteryx rugulosa, Psilopteryx psorosa species groups, Drusus bolivari, Annitella kosciuszkii species complexes (Trichoptera: Limnephilidae

    Directory of Open Access Journals (Sweden)

    Oláh, J.

    2015-06-01

    Full Text Available Speciation traits of paramere, paraproct and aedeagus were applied to find initial split criteria with fine structure analysis in order to prepare diverged trait matrices for delimiting phylogenetic incipient species of unsettled limnephilid taxa in the early stages of reproductive isolation. A brief history is presented how this phenotypic taxonomic tool of the speciation traits was discovered and applied in caddisfly taxonomy. The theoretical basis was elaborated for the phenotypic speciation trait by reviewing several relevant topics in the sciences of taxonomy, molecular genetics and phylogenetics. Perspectives of integrative taxonomy is discussed in context of phenotype versus genotype, immensely complex phenotype versus phenomic challenge, taxonomic impediment versus genetic expedient, taxonomic adaptation of genetic vocabulary versus genetic sophistication and virtualization, New Systematics of Huxley and Mayr versus New Taxonomy of Wheeler. Debates on magic trait, speciation phenotype, speciation trait and super traits are discussed concluding that evolution works with phenotype and why the cryptic species concept is irrelevant. Briefly summarized how speciation traits evolve in sexual selection, through accelerated reproductive isolation with genital evolution through sex-limited speciation traits, including minor sex chromosomes. Why neutral molecular markers are blind compared to the adaptive speciation traits sensitized by fine structure analysis and backed by the potential of high-tech and high-throughput phenotyping and cyber-infrastructure broadly accessible and fed by computable phenotype descriptions. What sort of genetics could really help taxonomy to describe biodiversity of the over 100 million unknown taxa? Collecting new and re-examining old type materials deposited in various collections, the following taxonomic actions were elaborated by speciation traits. Drusus bolivari new species complex has been erected with

  17. The Importance of some weeds for the survival of Fusarium oxysporum Schl. f.sp. lini (Boll. Snyd.

    Directory of Open Access Journals (Sweden)

    Barbara Łacicowa

    2014-08-01

    Full Text Available The studies were caried out to determine the importance of some weeds occurrence in the flax monoculture the survival of Fusarium oxysporum f. sp. lini. It appearet that the roots of Veronica persica, Stellaria media, Lamium purpureum, Capsella bursa-pastoris and Sonchus arvensis were colonized by Fusarium oxysporum f. sp. lini. V. persica especially has, a profitable influence on the survival of F. oxysporum f. sp. lini. However. C. hursa-pastoris and S. arvensis stimulate the growth of fungi of the genera Trichoderma. which limites the occurrence of F. oxysporum f. sp. lini in the soil.

  18. Fusarium oxysporum and F. verticillioides associated with damping-off in Pinus spp.

    Directory of Open Access Journals (Sweden)

    Caciara Gonzatto Maciel

    Full Text Available ABSTRACT Occurrence of Fusarium spp. is one of the problems, most limiting to growth of seedlings, in nurseries. This pathogen can be transmitted via seeds and causes damages to the seedlings during pre- and post-emergence stages. The present study aimed to identify Fusarium spp. at the species level based on morphological and molecular characteristics and to verify the pathogenicity of these isolates in seeds lots of Pinus elliottii and P. taeda. For this, we used two Fusarium isolates and five lots of Pinus spp. seeds. Morphological characterization was performed based on a key, specific to Fusarium spp. identification, whereas, molecular identification was carried out by amplification and sequencing of the regions from internal transcribed spacer (ITS and the elongation factor 1-α (tef1. The pathogenicity test was conducted through the contact of the seeds with fungal culture for 48 h, followed by sowing them in sand. The variables evaluated were emergency speed index, percentage of emergency, non-emergency seeds, symptomatic seedlings, and seedling damping-off. One isolate, F1UFSM, was identified as F. verticillioides and another isolate, F2UFSM, was identified as F. oxysporum. Both the isolates were pathogenic to the seeds of Pinus spp., causing a reduction in the percentage of emergence and seedling damping-off.

  19. The electronic structure of vanadium monochloride cation (VCl+): Tackling the complexities of transition metal species

    Science.gov (United States)

    DeYonker, Nathan J.; Halfen, DeWayne T.; Allen, Wesley D.; Ziurys, Lucy M.

    2014-11-01

    Six electronic states (X 4Σ-, A 4Π, B 4Δ, 2Φ, 2Δ, 2Σ+) of the vanadium monochloride cation (VCl+) are described using large basis set coupled cluster theory. For the two lowest quartet states (X 4Σ- and A 4Π), a focal point analysis (FPA) approach was used that conjoined a correlation-consistent family of basis sets up to aug-cc-pwCV5Z-DK with high-order coupled cluster theory through pentuple (CCSDTQP) excitations. FPA adiabatic excitation energies (T0) and spectroscopic constants (re, r0, Be, B0, bar De, He, ωe, v0, αe, ωexe) were extrapolated to the valence complete basis set Douglas-Kroll (DK) aug-cc-pV∞Z-DK CCSDT level of theory, and additional treatments accounted for higher-order valence electron correlation, core correlation, and spin-orbit coupling. Due to the delicate interplay between dynamical and static electronic correlation, single reference coupled cluster theory is able to provide the correct ground electronic state (X 4Σ-), while multireference configuration interaction theory cannot. Perturbations from the first- and second-order spin orbit coupling of low-lying states with quartet spin multiplicity reveal an immensely complex rotational spectrum relative to the isovalent species VO, VS, and TiCl. Computational data on the doublet manifold suggest that the lowest-lying doublet state (2Γ) has a Te of ˜11 200 cm-1. Overall, this study shows that laboratory and theoretical rotational spectroscopists must work more closely in tandem to better understand the bonding and structure of molecules containing transition metals.

  20. Identification and Genetic Characterization of Ralstonia solanacearum Species Complex Isolates from Cucurbita maxima in China

    Directory of Open Access Journals (Sweden)

    Xiaoman She

    2017-10-01

    Full Text Available Ralstonia solanacearum species complex is a devastating phytopathogen with an unusually wide host range, and new host plants are continuously being discovered. In June 2016, a new bacterial wilt on Cucurbita maxima was observed in Guangdong province, China. Initially, in the adult plant stage, several leaves of each plant withered suddenly and drooped; the plant then wilted completely, and the color of their vasculature changed to dark brown, ultimately causing the entire plant to die. Creamy-whitish bacterial masses were observed to ooze from crosscut stems of these diseased plants. To develop control strategies for C. maxima bacterial wilt, the causative pathogenic isolates were identified and characterized. Twenty-four bacterial isolates were obtained from diseased C. maxima plants, and 16S rRNA gene sequencing and pathogenicity analysis results indicated that the pathogen of C. maxima bacterial wilt was Ralstonia solanacearum. The results from DNA-based analysis, host range determination and bacteriological identification confirmed that the 24 isolates belonged to R. solanacearum phylotype I, race 1, and eight of these isolates belonged to biovar 3, while 16 belonged to biovar 4. Based on the results of partial egl gene sequence analysis, the 24 isolates clustered into three egl- sequence type groups, sequevars 17, 45, and 56. Sequevar 56 is a new sequevar which is described for the first time in this paper. An assessment of the resistance of 21 pumpkin cultivars revealed that C. moschata cv. Xiangyu1 is resistant to strain RS378, C. moschata cv. Xiangmi is moderately resistant to strain RS378, and 19 other pumpkin cultivars, including four C. maxima cultivars and 15 C. moschata cultivars, are susceptible to strain RS378. To the best of our knowledge, this is the first report of C. maxima bacterial wilt caused by R. solanacearum race 1 in the world. Our results provide valuable information for the further development of control strategies

  1. Identification and Genetic Characterization of Ralstonia solanacearum Species Complex Isolates from Cucurbita maxima in China.

    Science.gov (United States)

    She, Xiaoman; Yu, Lin; Lan, Guobing; Tang, Yafei; He, Zifu

    2017-01-01

    Ralstonia solanacearum species complex is a devastating phytopathogen with an unusually wide host range, and new host plants are continuously being discovered. In June 2016, a new bacterial wilt on Cucurbita maxima was observed in Guangdong province, China. Initially, in the adult plant stage, several leaves of each plant withered suddenly and drooped; the plant then wilted completely, and the color of their vasculature changed to dark brown, ultimately causing the entire plant to die. Creamy-whitish bacterial masses were observed to ooze from crosscut stems of these diseased plants. To develop control strategies for C. maxima bacterial wilt, the causative pathogenic isolates were identified and characterized. Twenty-four bacterial isolates were obtained from diseased C. maxima plants, and 16S rRNA gene sequencing and pathogenicity analysis results indicated that the pathogen of C. maxima bacterial wilt was Ralstonia solanacearum . The results from DNA-based analysis, host range determination and bacteriological identification confirmed that the 24 isolates belonged to R. solanacearum phylotype I, race 1, and eight of these isolates belonged to biovar 3, while 16 belonged to biovar 4. Based on the results of partial egl gene sequence analysis, the 24 isolates clustered into three egl- sequence type groups, sequevars 17, 45, and 56. Sequevar 56 is a new sequevar which is described for the first time in this paper. An assessment of the resistance of 21 pumpkin cultivars revealed that C. moschata cv. Xiangyu1 is resistant to strain RS378, C. moschata cv. Xiangmi is moderately resistant to strain RS378, and 19 other pumpkin cultivars, including four C. maxima cultivars and 15 C. moschata cultivars, are susceptible to strain RS378. To the best of our knowledge, this is the first report of C. maxima bacterial wilt caused by R. solanacearum race 1 in the world. Our results provide valuable information for the further development of control strategies for C. maxima wilt

  2. Identifying designatable units for intraspecific conservation prioritization: a hierarchical approach applied to the lake whitefish species complex (Coregonus spp.).

    Science.gov (United States)

    Mee, Jonathan A; Bernatchez, Louis; Reist, Jim D; Rogers, Sean M; Taylor, Eric B

    2015-06-01

    The concept of the designatable unit (DU) affords a practical approach to identifying diversity below the species level for conservation prioritization. However, its suitability for defining conservation units in ecologically diverse, geographically widespread and taxonomically challenging species complexes has not been broadly evaluated. The lake whitefish species complex (Coregonus spp.) is geographically widespread in the Northern Hemisphere, and it contains a great deal of variability in ecology and evolutionary legacy within and among populations, as well as a great deal of taxonomic ambiguity. Here, we employ a set of hierarchical criteria to identify DUs within the Canadian distribution of the lake whitefish species complex. We identified 36 DUs based on (i) reproductive isolation, (ii) phylogeographic groupings, (iii) local adaptation and (iv) biogeographic regions. The identification of DUs is required for clear discussion regarding the conservation prioritization of lake whitefish populations. We suggest conservation priorities among lake whitefish DUs based on biological consequences of extinction, risk of extinction and distinctiveness. Our results exemplify the need for extensive genetic and biogeographic analyses for any species with broad geographic distributions and the need for detailed evaluation of evolutionary history and adaptive ecological divergence when defining intraspecific conservation units.

  3. Secondary metabolite comparison of the species within the Heterobasidion annosum s.l. complex

    DEFF Research Database (Denmark)

    Hansson, David; Wubshet, Sileshi Gizachew; Olson, Åke

    2014-01-01

    The metabolite production of the five members of the fungal species complex Heterobasidion annosum s.l., i.e. H. annosum s.s., H. abietinum, H. parviporum, H. occidentale and H. irregulare, was analyzed by LC–HRMS. The five members are described to have differences in host preferences: H. annosum...

  4. Peptaibol, Secondary‐Metabolite, and Hydrophobin Pattern of Commercial Biocontrol Agents Formulated with Species of the Trichoderma harzianum Complex

    DEFF Research Database (Denmark)

    Degenkolb, Thomas; Nielsen, Kristian Fog; Dieckmann, Ralf

    2015-01-01

    The production of bioactive polypeptides (peptaibiotics) in vivo is a sophisticated adaptation strategy of both mycoparasitic and saprotrophic Trichoderma species for colonizing and defending their natural habitats. This feature is of major practical importance, as the detection of peptaibiotics...... in plant‐protective Trichoderma species, which are successfully used against economically relevant bacterial and fungal plant pathogens, certainly contributes to a better understanding of these complex antagonistic interactions. We analyzed five commercial biocontrol agents (BCAs), namely Canna®, Trichosan......®, Vitalin®, Promot® WP, and TrichoMax®, formulated with recently described species of the Trichoderma harzianum complex, viz. T. afroharzianum, T. simmonsii, and T. guizhouense. By using the well‐established, HPLC/MS‐based peptaibiomics approach, it could unequivocally be demonstrated that all...

  5. Development and validation of a multi-locus DNA metabarcoding method to identify endangered species in complex samples.

    Science.gov (United States)

    Arulandhu, Alfred J; Staats, Martijn; Hagelaar, Rico; Voorhuijzen, Marleen M; Prins, Theo W; Scholtens, Ingrid; Costessi, Adalberto; Duijsings, Danny; Rechenmann, François; Gaspar, Frédéric B; Barreto Crespo, Maria Teresa; Holst-Jensen, Arne; Birck, Matthew; Burns, Malcolm; Haynes, Edward; Hochegger, Rupert; Klingl, Alexander; Lundberg, Lisa; Natale, Chiara; Niekamp, Hauke; Perri, Elena; Barbante, Alessandra; Rosec, Jean-Philippe; Seyfarth, Ralf; Sovová, Tereza; Van Moorleghem, Christoff; van Ruth, Saskia; Peelen, Tamara; Kok, Esther

    2017-10-01

    DNA metabarcoding provides great potential for species identification in complex samples such as food supplements and traditional medicines. Such a method would aid Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) enforcement officers to combat wildlife crime by preventing illegal trade of endangered plant and animal species. The objective of this research was to develop a multi-locus DNA metabarcoding method for forensic wildlife species identification and to evaluate the applicability and reproducibility of this approach across different laboratories. A DNA metabarcoding method was developed that makes use of 12 DNA barcode markers that have demonstrated universal applicability across a wide range of plant and animal taxa and that facilitate the identification of species in samples containing degraded DNA. The DNA metabarcoding method was developed based on Illumina MiSeq amplicon sequencing of well-defined experimental mixtures, for which a bioinformatics pipeline with user-friendly web-interface was developed. The performance of the DNA metabarcoding method was assessed in an international validation trial by 16 laboratories, in which the method was found to be highly reproducible and sensitive enough to identify species present in a mixture at 1% dry weight content. The advanced multi-locus DNA metabarcoding method assessed in this study provides reliable and detailed data on the composition of complex food products, including information on the presence of CITES-listed species. The method can provide improved resolution for species identification, while verifying species with multiple DNA barcodes contributes to an enhanced quality assurance. © The Authors 2017. Published by Oxford University Press.

  6. Comparative “Omics” of the Fusarium fujikuroi Species Complex Highlights Differences in Genetic Potential and Metabolite Synthesis

    Science.gov (United States)

    Niehaus, Eva-Maria; Münsterkötter, Martin; Proctor, Robert H.; Brown, Daren W.; Sharon, Amir; Idan, Yifat; Oren-Young, Liat; Sieber, Christian M.; Novák, Ondřej; Pěnčík, Aleš; Tarkowská, Danuše; Hromadová, Kristýna; Freeman, Stanley; Maymon, Marcel; Elazar, Meirav; Youssef, Sahar A.; El-Shabrawy, El Said M.; Shalaby, Abdel Baset A.; Houterman, Petra; Brock, Nelson L.; Burkhardt, Immo; Tsavkelova, Elena A.; Dickschat, Jeroen S.; Galuszka, Petr; Güldener, Ulrich; Tudzynski, Bettina

    2016-01-01

    Species of the Fusarium fujikuroi species complex (FFC) cause a wide spectrum of often devastating diseases on diverse agricultural crops, including coffee, fig, mango, maize, rice, and sugarcane. Although species within the FFC are difficult to distinguish by morphology, and their genes often share 90% sequence similarity, they can differ in host plant specificity and life style. FFC species can also produce structurally diverse secondary metabolites (SMs), including the mycotoxins fumonisins, fusarins, fusaric acid, and beauvericin, and the phytohormones gibberellins, auxins, and cytokinins. The spectrum of SMs produced can differ among closely related species, suggesting that SMs might be determinants of host specificity. To date, genomes of only a limited number of FFC species have been sequenced. Here, we provide draft genome sequences of three more members of the FFC: a single isolate of F. mangiferae, the cause of mango malformation, and two isolates of F. proliferatum, one a pathogen of maize and the other an orchid endophyte. We compared these genomes to publicly available genome sequences of three other FFC species. The comparisons revealed species-specific and isolate-specific differences in the composition and expression (in vitro and in planta) of genes involved in SM production including those for phytohormome biosynthesis. Such differences have the potential to impact host specificity and, as in the case of F. proliferatum, the pathogenic versus endophytic life style. PMID:28040774

  7. The Diaporthe sojae species complex: Phylogenetic re-assessment of pathogens associated with soybean, cucurbits and other field crops.

    Science.gov (United States)

    Udayanga, Dhanushka; Castlebury, Lisa A; Rossman, Amy Y; Chukeatirote, Ekachai; Hyde, Kevin D

    2015-05-01

    Phytopathogenic species of Diaporthe are associated with a number of soybean diseases including seed decay, pod and stem blight and stem canker and lead to considerable crop production losses worldwide. Accurate morphological identification of the species that cause these diseases has been difficult. In this study, we determined the phylogenetic relationships and species boundaries of Diaporthe longicolla, Diaporthe phaseolorum, Diaporthe sojae and closely related taxa. Species boundaries for this complex were determined based on combined phylogenetic analysis of five gene regions: partial sequences of calmodulin (CAL), beta-tubulin (TUB), histone-3 (HIS), translation elongation factor 1-α (EF1-α), and the nuclear ribosomal internal transcribed spacers (ITS). Phylogenetic analyses revealed that this large complex of taxa is comprised of soybean pathogens as well as species associated with herbaceous field crops and weeds. Diaporthe arctii, Diaporthe batatas, D. phaseolorum and D. sojae are epitypified. The seed decay pathogen D. longicolla was determined to be distinct from D. sojae. D. phaseolorum, originally associated with stem and leaf blight of Lima bean, was not found to be associated with soybean. A new species, Diaporthe ueckerae on Cucumis melo, is introduced with description and illustrations. Published by Elsevier Ltd.

  8. A Simple Key for Identifying the Sibling Species of the Malaria Vector Anopheles gambiae (Giles Complex by Polytene Chromosome Cytogenetics

    Directory of Open Access Journals (Sweden)

    Music Temitope OBEMBE

    2018-03-01

    Full Text Available It has been established that Anopheles gambiae complex sibling species are the major Plasmodium malaria vectors in Africa; however, not all the sibling species transmit the infection. Easier molecular methods, PCR-based assays, have been developed to distinguish the several members of the A. gambiae complex. However, malaria vector research in less developed countries, particularly sub-Saharan Africa, is being hampered by the lack of PCR facilities in laboratories and the cost of carrying out the assay within lack of funding. Hence, the present study was designed to develop a simple identification key, based on an affordable method of polytene chromosome cytotaxonomy, for identifying the major P. falciparum vectors. The Identification Key was successfully used to identify two members of the A. gambiae complex, A. gambiae sensu stricto and A. arabiensis, which are the most potent malaria vectors in Africa; even so, it could not be used to establish the infective and the refractory strains.

  9. Is agriculture driving the diversification of the Bemisia tabaci species complex (Hemiptera: Sternorrhyncha: Aleyrodidae)?: Dating, diversification and biogeographic evidence revealed.

    Science.gov (United States)

    Boykin, Laura M; Bell, Charles D; Evans, Gregory; Small, Ian; De Barro, Paul J

    2013-10-18

    Humans and insect herbivores are competing for the same food crops and have been for thousands of years. Despite considerable advances in crop pest management, losses due to insects remain considerable. The global homogenisation of agriculture has supported the range expansion of numerous insect pests and has been driven in part by human-assisted dispersal supported through rapid global trade and low-cost air passenger transport. One of these pests, is the whitefly, Bemisia tabaci, a cryptic species complex that contains some of the world's most damaging pests of agriculture. The complex shows considerable genetic diversity and strong phylogeographic relationships. One consequence of the considerable impact that members of the B. tabaci complex have on agriculture, is the view that human activity, particularly in relation to agricultural practices, such as use of insecticides, has driven the diversification found within the species complex. This has been particularly so in the case of two members of the complex, Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED), which have become globally distributed invasive species. An alternative hypothesis is that diversification is due to paleogeographic and paleoclimatological changes. The idea that human activity is driving speciation within the B. tabaci complex has never been tested, but the increased interest in fossil whiteflies and the growth in molecular data have enabled us to apply a relaxed molecular clock and so estimate divergence dates for the major lineages within the B. tabaci species complex. The divergence estimates do not support the view that human activity has been a major driver of diversification. Our analysis suggests that the major lineages within the complex arose approximately 60-30 mya and the highly invasive MED and MEAM1 split from the rest of the species complex around 12 mya well before the evolution of Homo sapiens and agriculture. Furthermore, the divergence dates coincide with a period

  10. A nonpathogenic Fusarium oxysporum strain enhances phytoextraction of heavy metals by the hyperaccumulator Sedum alfredii Hance.

    Science.gov (United States)

    Zhang, Xincheng; Lin, Li; Chen, Mingyue; Zhu, Zhiqiang; Yang, Weidong; Chen, Bao; Yang, Xiaoe; An, Qianli

    2012-08-30

    Low biomass and shallow root systems limit the application of heavy metal phytoextraction by hyperaccumulators. Plant growth-promoting microbes may enhance hyperaccumulators'phytoextraction. A heavy metal-resistant fungus belonged to the Fusarium oxysporum complex was isolated from the Zn/Cd co-hyperaccumulator Sedum alfredii Hance grown in a Pb/Zn mined area. This Fusarium fungus was not pathogenic to plants but promoted host growth. Hydroponic experiments showed that 500 μM Zn(2+) or 50 μM Cd(2+) combined with the fungus increased root length, branches, and surface areas, enhanced nutrient uptake and chlorophyll synthesis, leading to more vigorous hyperaccumulators with greater root systems. Soil experiments showed that the fungus increased root and shoot biomass and S. alfredii-mediated heavy metal availabilities, uptake, translocation or concentrations, and thus increased phytoextraction of Zn (144% and 44%), Cd (139% and 55%), Pb (84% and 85%) and Cu (63% and 77%) from the original Pb/Zn mined soil and a multi-metal contaminated paddy soil. Together, the nonpathogenic Fusarium fungus was able to increase S. alfredii root systems and function, metal availability and accumulation, plant biomass, and thus phytoextraction efficiency. This study showed a great application potential for culturable indigenous fungi other than symbiotic mycorrhizas to enhance the phytoextraction by hyperaccumulators. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Biotechnological tools against Fusarium oxysporum f. sp. cubense Tropical race 4 in Musa spp.

    Directory of Open Access Journals (Sweden)

    Idalmis Bermúdez-Caraballoso

    2014-10-01

    attacking Musa worldwide. Race 1 caused an epidemic that destroyed the banana export industry based cultivar ‘Gros Michel’ (Musa AAA in America as well as the disappearance of commercial production of cultivar ‘Manzano’ (Musa AAB in Cuba. The Foc tropical race 4 (TR4 was first recognized in 1990 in Taiwan, causing serious damage to the standards for the export crops sub Cavendish group in several countries in Southeast Asia. Most troubling is that over 80% banana cultivars produced worldwide are susceptibles to this race, and thus represents a potential risk for producing countries of Latin America and the Caribbean where threat has not yet reached the pathogen. This review was conducted with the aim of presenting the possible implications of the entry into Cuba of tropical race 4 of Panama disease and strategies to prevent future damages caused by the disease. Include aspects of the symptomatology of the disease, mechanisms of infection, pathogenic complexity and dispersion of the pathogen as well as several biotechnological tools against the disease among which are: varietal resistance, resistance inducers and development of tolerant cultivars. Key words: bananas, fungi disease, Fusarium oxysporum, plantains, varietal resistance

  12. Speciation on the rocks: integrated systematics of the Heteronotia spelea species complex (Gekkota; Reptilia from Western and Central Australia.

    Directory of Open Access Journals (Sweden)

    Mitzy Pepper

    Full Text Available The isolated uplands of the Australian arid zone are known to provide mesic refuges in an otherwise xeric landscape, and divergent lineages of largely arid zone taxa have persisted in these regions following the onset of Miocene aridification. Geckos of the genus Heteronotia are one such group, and have been the subject of many genetic studies, including H. spelea, a strongly banded form that occurs in the uplands of the Pilbara and Central Ranges regions of the Australian arid zone. Here we assess the systematics of these geckos based on detailed examination of morphological and genetic variation. The H. spelea species complex is a monophyletic lineage to the exclusion of the H. binoei and H. planiceps species complexes. Within the H. spelea complex, our previous studies based on mtDNA and nine nDNA loci found populations from the Central Ranges to be genetically divergent from Pilbara populations. Here we supplement our published molecular data with additional data gathered from central Australian samples. In the spirit of integrative species delimitation, we combine multi-locus, coalescent-based lineage delimitation with extensive morphological analyses to test species boundaries, and we describe the central populations as a new species, H. fasciolatus sp. nov. In addition, within the Pilbara there is strong genetic evidence for three lineages corresponding to northeastern (type, southern, and a large-bodied melanic population isolated in the northwest. Due to its genetic distinctiveness and extreme morphological divergence from all other Heteronotia, we describe the melanic form as a new species, H. atra sp. nov. The northeastern and southern Pilbara populations are morphologically indistinguishable with the exception of a morpho-type in the southeast that has a banding pattern resembling H. planiceps from the northern monsoonal tropics. Pending more extensive analyses, we therefore treat Pilbara H. spelea as a single species with

  13. What Can Molecular Markers Tell Us About the Evolutionary History of Daphnia Species Complexes

    NARCIS (Netherlands)

    Schwenk, K.; Ender, A.; Streit, B.

    1995-01-01

    Despite the wealth of information on the ecology of Daphnia species, the systematics and phylogeny of the genus is still unresolved. The taxonomic uncertainties are based in part on the phenomenon of interspecific hybridization, which has been well documented for species of the D.

  14. Amyloidity is not diagnostic for species in the Mycena pearsoniana complex (Mycena sectio Calodontes)

    Science.gov (United States)

    Christoffer Bugge Harder; D. Jean Lodge; Ronald H. Petersen; Karen W. Hughes; Joaquin Cifuentes Blanco; Tobias Guldberg Froslev; Thomas. L& #230; ssoe

    2012-01-01

    Mycena sectio Calodontes with otherwise amyloid spores, the inamyloid spores of Mycena pearsoniana Dennis ex Singer were a distinguishing feature for this species and its subsection Violacella. Although the original concept of this species was European, Singer chose to typify it with material...

  15. Cytogenetic Evidence for a Complex of Species within the Taxon Anopheles maculatus (Diptera: Culicidae)

    Science.gov (United States)

    1985-01-01

    condition . Both Y, and Y, are associated with species B and forms E and F; however, they show geographic variation. Chromosome Y, does not occur (or is...Heterochromatin and karyotypic differentiation of some Neotropical cactus-breeding species of the Drosophila replctu group. Genetica 60: 81-92

  16. High spatial resolution spectral unmixing for mapping ash species across a complex urban environment

    Science.gov (United States)

    Jennifer Pontius; Ryan P. Hanavan; Richard A. Hallett; Bruce D. Cook; Lawrence A. Corp

    2017-01-01

    Ash (Fraxinus L.) species are currently threatened by the emerald ash borer (EAB; Agrilus planipennis Fairmaire) across a growing area in the eastern US. Accurate mapping of ash species is required to monitor the host resource, predict EAB spread and better understand the short- and long-term effects of EAB on the ash resource...

  17. Species of the Hoplias aff malabaricus complex (Characiformes: Erythrinidae: An investigation of coexistence in a Neotropical floodplain

    Directory of Open Access Journals (Sweden)

    Marília Hauser

    2012-02-01

    Full Text Available This study assessed the coexistence of three species of thraira present in the Upper Paraná River floodplain, using population structure as an investigation tool. The species were designated as: Hoplias sp. 1, introduced after the construction of the Itaipu reservoir, and Hoplias sp. 2 and Hoplias sp. 3, native species that have been identified as Hoplias aff. malabaricus. We tested the hypothesis that those species in fact differ from each other in respect of population abundance, sex ratio, relative frequency of adults and juveniles, length structure and weight-length relationship. Additionally, possible effects of the flood pulse on the first four of these parameters were investigated. Samples were collected quarterly from March 2006 to December 2007 from nine collection sites on the floodplain. Hoplias sp. 1 presented a greater balance of sex ratio and length structures over the seasons, as well as a higher allometric coefficient. The population attributes of Hoplias sp. 2 and Hoplias sp. 3 showed a high responsiveness to hydrological seasonality, indicating that these species exploit available resources in a conspicuous flood period with greater efficiency. These differences, beyond reflecting possible mechanisms that allow closely related species to coexist, indicate the importance of understanding the life strategies adopted by each species which, as part of a complex system, are considered key elements of the aquatic community structure in the region, providing important information for habitat management and biodiversity conservation.

  18. Recognition and identification of bumblebee species in the Bombus lucorum-complex (Hymenoptera, Apidae – A review and outlook

    Directory of Open Access Journals (Sweden)

    Silas Bossert

    2015-02-01

    Full Text Available The recognition of cryptic species represents one of the major challenges in current taxonomy and affects our understanding of global diversity. In practice, the process from discovery to acceptance in the scientific community can take an extensive length of time. A prime example is the traditionally difficult taxonomy of the cryptic bumblebee species belonging to the Bombus lucorum-complex. The status of the three European species in the group – Bombus lucorum and the closely related Bombus cryptarum and Bombus magnus – has recently become widely accepted, primarily due to investigations of nucleotide sequences and marking pheromones. In contrast, doubts prevail concerning the validity of species identification based on morphology. As a consequence, our knowledge of the species is muddled in a mire of unreliable and confusing literature data from a large number of authors over the centuries. To clarify this issue, this paper provides a recapitulation of the historical literature and highlights the milestones in the process of species recognition. Further, the possibility of a morphologically based species identification is discussed in the context of new molecular data. Finally, this review outlines the current challenges and provides directions for future issues.

  19. Deciphering the complex leaf transcriptome of the allotetraploid species Nicotiana tabacum: a phylogenomic perspective

    Directory of Open Access Journals (Sweden)

    Bombarely Aureliano

    2012-08-01

    Full Text Available Abstract Background Polyploidization is an important mechanism in plant evolution. By analyzing the leaf transcriptomes taken from the allotetraploid Nicotiana tabacum (tobacco and parental genome donors, N. sylvesteris (S-Genome and N. tomentosiformis (T-Genome, a phylogenomic approach was taken to map the fate of homeologous gene pairs in this plant. Results A comparison between the genes present in the leaf transcriptomes of N. tabacum and modern day representatives of its progenitor species demonstrated that only 33% of assembled transcripts could be distinguished based on their sequences. A large majority of the genes (83.6% of the non parent distinguishable and 87.2% of the phylogenetic topology analyzed clusters expressed above background level (more than 5 reads showed similar overall expression levels. Homeologous sequences could be identified for 968 gene clusters, and 90% (6% of all genes of the set maintained expression of only one of the tobacco homeologs. When both homeologs were expressed, only 15% (0.5% of the total showed evidence of differential expression, providing limited evidence of subfunctionalization. Comparing the rate of synonymous nucleotide substitution (Ks and non-synonymous nucleotide substitution (Kn provided limited evidence for positive selection during the evolution of tobacco since the polyploidization event took place. Conclusions Polyploidization is a powerful mechanism for plant speciation that can occur during one generation; however millions of generations may be necessary for duplicate genes to acquire a new function. Analysis of the tobacco leaf transcriptome reveals that polyploidization, even in a young tetraploid such as tobacco, can lead to complex changes in gene expression. Gene loss and gene silencing, or subfunctionalization may explain why both homeologs are not expressed by the associated genes. With Whole Genome Duplication (WGD events, polyploid genomes usually maintain a high percentage of

  20. Role of genotype® mycobacterium common mycobacteria/additional species assay for rapid differentiation between Mycobacterium tuberculosis complex and different species of non-tuberculous mycobacteria

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    Amresh Kumar Singh

    2013-01-01

    Full Text Available Background: Mycobacterium tuberculosis complex (MTBC and non-tuberculous mycobacteria (NTM may or may not have same clinical presentations, but the treatment regimens are always different. Laboratory differentiation between MTBC and NTM by routine methods are time consuming and cumbersome to perform. We have evaluated the role of GenoType® Mycobacterium common mycobacteria/additional species (CM/AS assay for differentiation between MTBC and different species of NTM in clinical isolates from tuberculosis (TB cases. Materials and Methods: A total of 1080 clinical specimens were collected from January 2010 to June 2012. Diagnosis was performed by Ziehl-Neelsen staining followed by culture in BacT/ALERT 3D system (bioMerieux, France. A total of 219 culture positive clinical isolates (BacT/ALERT® MP cultures were selected for differentiation by p-nitrobenzoic acid (PNB sensitivity test as and BIO-LINE SD Ag MPT64 TB test considering as the gold standard test. Final identification and differentiation between MTBC and different species of NTM were further confirmed by GenoType® Mycobacterium CM/AS assay (Hain Lifescience, Nehren, Germany. Results: Out of 219 BacT/ALERT® MP culture positive isolates tested by PNB as 153 MTBC (69.9% and by GenoType® Mycobacterium CM/AS assay as 159 (72.6% MTBC and remaining 60 (27.4% were considered as NTM species. The GenoType® Mycobacterium CM/AS assay was proved 99.3% sensitive and 98.3% specific for rapid differentiation of MTBC and NTM. The most common NTM species were; Mycobacterium fortuitum 20 (33.3% among rapid growing mycobacteria and Mycobacterium intracellulare 11 (18.3% among slow growing mycobacteria. Conclusion: The GenoType® Mycobacterium assay makes rapid and accurate identification of NTM species as compared with different phenotypic and molecular diagnostic tool and helps in management of infections caused by different mycobacteria.

  1. Evaluation of molecular species of prostate-specific antigen complexed with immunoglobulin M in prostate cancer and benign prostatic hyperplasia.

    Science.gov (United States)

    Goč, Sanja; Janković, Miroslava

    2013-01-01

    This study was aimed at defining molecular species of prostate-specific antigen (PSA) in immune complexes with immunoglobulin M (IgM). Having in mind the oligoreactivity of IgM and its preference for carbohydrate antigens, there is the possibility that it can selectively recognize known PSA glycoisoforms. PSA-IgM complexes and free PSA fractions were separated from the sera of subjects with prostate cancer (PCa) and benign prostatic hyperplasia (BPH) by gel filtration and subjected to on-chip immunoaffinity and ion-exchange chromatography. PSA-immunoreactive species were detected using surface-enhanced laser desorption/ionization time of flight mass spectrometry. The obtained spectra were analyzed for protein and glycan composition. The general pattern of the molecular species of PCa PSA and BPH PSA found in complexes with IgM was similar. It comprised major peaks at 17 kDa and minor peaks at 28 kDa, corresponding to the entire mature glycosylated PSA. The main difference was the presence of incompletely glycosylated 26.8 kDa species, having putative paucimannosidic structures, observed in PCa PSA-IgM, but not in BPH PSA-IgM. Characteristic PCa PSA-IgM glycoforms pose the question of the possible role of glycosylation as a framework for immune surveillance and may be of interest in light of recent data indicating mannose-containing glycans as cancer biomarker.

  2. Evaluation of Molecular Species of Prostate-Specific Antigen Complexed with Immunoglobulin M in Prostate Cancer and Benign Prostatic Hyperplasia

    Directory of Open Access Journals (Sweden)

    Sanja Goč

    2013-01-01

    Full Text Available This study was aimed at defining molecular species of prostate-specific antigen (PSA in immune complexes with immunoglobulin M (IgM. Having in mind the oligoreactivity of IgM and its preference for carbohydrate antigens, there is the possibility that it can selectively recognize known PSA glycoisoforms. PSA-IgM complexes and free PSA fractions were separated from the sera of subjects with prostate cancer (PCa and benign prostatic hyperplasia (BPH by gel filtration and subjected to on-chip immunoaffinity and ion-exchange chromatography. PSA-immunoreactive species were detected using surface-enhanced laser desorption/ionization time of flight mass spectrometry. The obtained spectra were analyzed for protein and glycan composition. The general pattern of the molecular species of PCa PSA and BPH PSA found in complexes with IgM was similar. It comprised major peaks at 17 kDa and minor peaks at 28 kDa, corresponding to the entire mature glycosylated PSA. The main difference was the presence of incompletely glycosylated 26.8 kDa species, having putative paucimannosidic structures, observed in PCa PSA-IgM, but not in BPH PSA-IgM. Characteristic PCa PSA-IgM glycoforms pose the question of the possible role of glycosylation as a framework for immune surveillance and may be of interest in light of recent data indicating mannose-containing glycans as cancer biomarker.

  3. Simulated tri-trophic networks reveal complex relationships between species diversity and interaction diversity.

    Science.gov (United States)

    Pardikes, Nicholas A; Lumpkin, Will; Hurtado, Paul J; Dyer, Lee A

    2018-01-01

    Most of earth's biodiversity is comprised of interactions among species, yet it is unclear what causes variation in interaction diversity across space and time. We define interaction diversity as the richness and relative abundance of interactions linking species together at scales from localized, measurable webs to entire ecosystems. Large-scale patterns suggest that two basic components of interaction diversity differ substantially and predictably between different ecosystems: overall taxonomic diversity and host specificity of consumers. Understanding how these factors influence interaction diversity, and quantifying the causes and effects of variation in interaction diversity are important goals for community ecology. While previous studies have examined the effects of sampling bias and consumer specialization on determining patterns of ecological networks, these studies were restricted to two trophic levels and did not incorporate realistic variation in species diversity and consumer diet breadth. Here, we developed a food web model to generate tri-trophic ecological networks, and evaluated specific hypotheses about how the diversity of trophic interactions and species diversity are related under different scenarios of species richness, taxonomic abundance, and consumer diet breadth. We investigated the accumulation of species and interactions and found that interactions accumulate more quickly; thus, the accumulation of novel interactions may require less sampling effort than sampling species in order to get reliable estimates of either type of diversity. Mean consumer diet breadth influenced the correlation between species and interaction diversity significantly more than variation in both species richness and taxonomic abundance. However, this effect of diet breadth on interaction diversity is conditional on the number of observed interactions included in the models. The results presented here will help develop realistic predictions of the relationships

  4. Improvement of MALDI-TOF MS profiling for the differentiation of species within the Acinetobacter calcoaceticus-Acinetobacter baumannii complex.

    Science.gov (United States)

    Šedo, Ondrej; Nemec, Alexandr; Křížová, Lenka; Kačalová, Magdaléna; Zdráhal, Zbyněk

    2013-12-01

    MALDI-TOF MS is currently becoming the method of choice for rapid identification of bacterial species in routine diagnostics. Yet, this method suffers from the inability to differentiate reliably between some closely related bacterial species including those of the Acinetobacter calcoaceticus-Acinetobacter baumannii (ACB) complex, namely A. baumannii and Acinetobacter nosocomialis. In the present study, we evaluated a protocol which was different from that used in the Bruker Daltonics identification system (MALDI BioTyper) to improve species identification using a taxonomically precisely defined set of 105 strains representing the four validly named species of the ACB complex. The novel protocol is based on the change in matrix composition from alpha-cyano-4-hydroxycinnamic acid (saturated solution in water:acetonitrile:trifluoroacetic acid, 47.5:50:2.5, v/v) to ferulic acid (12.5mgml(-1) solution in water:acetonitrile:formic acid 50:33:17, v/v), while the other steps of sample processing remain unchanged. Compared to the standard protocol, the novel one extended the range of detected compounds towards higher molecular weight, produced signals with better mass resolution, and allowed the detection of species-specific signals. As a result, differentiation of A. nosocomialis and A. baumannii strains by cluster analysis was improved and 13 A. nosocomialis strains, assigned erroneously or ambiguously by using the standard protocol, were correctly identified. Copyright © 2013 Elsevier GmbH. All rights reserved.

  5. Phylogeography, colonization and population history of the Midas cichlid species complex (Amphilophus spp. in the Nicaraguan crater lakes

    Directory of Open Access Journals (Sweden)

    Meyer Axel

    2010-10-01

    Full Text Available Abstract Background Elucidation of the mechanisms driving speciation requires detailed knowledge about the phylogenetic relationships and phylogeography of the incipient species within their entire ranges as well as their colonization history. The Midas cichlid species complex Amphilophus spp. has been proven to be a powerful model system for the study of ecological specialization, sexual selection and the mechanisms of sympatric speciation. Here we present a comprehensive and integrative phylogeographic analysis of the complete Midas Cichlid species complex in Nicaragua (> 2000 individuals covering the entire distributional range, using two types of molecular markers (the mitochondrial DNA control region and 15 microsatellites. We investigated the majority of known lake populations of this species complex and reconstructed their colonization history in order to distinguish between alternative speciation scenarios. Results We found that the large lakes contain older and more diverse Midas Cichlid populations, while all crater lakes hold younger and genetically less variable species assemblages. The large lakes appear to have repeatedly acted as source populations for all crater lakes, and our data indicate that faunal exchange among crater lakes is extremely unlikely. Despite their very recent (often only a few thousand years old and common origin from the two large Nicaraguan lakes, all crater lake Midas Cichlid radiations underwent independent, but parallel, evolution, and comprise distinct genetic units. Indeed several of these crater lakes contain multiple genetically distinct incipient species that most likely arose through sympatric speciation. Several crater lake radiations can be traced back to a single ancestral line, but some appear to have more than one founding lineage. The timing of the colonization(s of each crater lake differs, although most of them occurred more (probably much more recently than 20,000 years ago. Conclusion The

  6. Vicariance and Its Impact on the Molecular Ecology of a Chinese Ranid Frog Species-Complex (Odorrana schmackeri, Ranidae.

    Directory of Open Access Journals (Sweden)

    Yongmin Li

    Full Text Available Paleogeological events and Pleistocene climatic fluctuations have had profound influences on the genetic patterns and phylogeographic structure of species in southern China. In this study, we investigated the population genetic structure and Phylogeography of the Odorrana schmackeri species complex, mountain stream-dwelling odorous frogs, endemic to southern China. We obtained mitochondrial sequences (1,151bp of the complete ND2 gene and two flanking tRNAs of 511 individuals from 25 sites for phylogeographic analyses. Phylogenetic reconstruction revealed seven divergent evolutionary lineages, with mean pairwise (K2P sequence distances from 7.8% to 21.1%, except for a closer ND2 distance (3.4%. The complex geological history of southern China drove matrilineal divergence in the O. schmackeri species complex into highly structured geographical units. The first divergence between lineage A+B and other lineages (C-G had likely been influenced by the uplift of coastal mountains of Southeast China during the Mio-Pliocene period. The subsequent divergences between the lineages C-G may have followed the formation of the Three Gorges and the intensification of the East Asian summer monsoon during the late Pliocene and early Pleistocene. Demographic analyses indicated that major lineages A and C have been experienced recent population expansion (c. 0.045-0.245 Ma from multiple refugia prior to the Last Glacial Maximum (LGM. Molecular analysis suggest that these seven lineages may represent seven different species, three described species and four cryptic species and should at least be separated into seven management units corresponding to these seven geographic lineages for conservation.

  7. Phylogeography, colonization and population history of the Midas cichlid species complex (Amphilophus spp.) in the Nicaraguan crater lakes.

    Science.gov (United States)

    Barluenga, Marta; Meyer, Axel

    2010-10-26

    Elucidation of the mechanisms driving speciation requires detailed knowledge about the phylogenetic relationships and phylogeography of the incipient species within their entire ranges as well as their colonization history. The Midas cichlid species complex Amphilophus spp. has been proven to be a powerful model system for the study of ecological specialization, sexual selection and the mechanisms of sympatric speciation. Here we present a comprehensive and integrative phylogeographic analysis of the complete Midas Cichlid species complex in Nicaragua (> 2000 individuals) covering the entire distributional range, using two types of molecular markers (the mitochondrial DNA control region and 15 microsatellites). We investigated the majority of known lake populations of this species complex and reconstructed their colonization history in order to distinguish between alternative speciation scenarios. We found that the large lakes contain older and more diverse Midas Cichlid populations, while all crater lakes hold younger and genetically less variable species assemblages. The large lakes appear to have repeatedly acted as source populations for all crater lakes, and our data indicate that faunal exchange among crater lakes is extremely unlikely. Despite their very recent (often only a few thousand years old) and common origin from the two large Nicaraguan lakes, all crater lake Midas Cichlid radiations underwent independent, but parallel, evolution, and comprise distinct genetic units. Indeed several of these crater lakes contain multiple genetically distinct incipient species that most likely arose through sympatric speciation. Several crater lake radiations can be traced back to a single ancestral line, but some appear to have more than one founding lineage. The timing of the colonization(s) of each crater lake differs, although most of them occurred more (probably much more) recently than 20,000 years ago. The genetic differentiation of the crater lake populations

  8. Inter and intra-guild interactions in egg parasitoid species of the soybean stink bug complex

    Directory of Open Access Journals (Sweden)

    Sujii Edison Ryoiti

    2002-01-01

    Full Text Available The objective of this research was to evaluate the parasitism behavior of Telenomus podisi Ashmead, Trissolcus basalis (Wollaston e Trissolcus urichi Crawford (Hymenoptera: Scelionidae on eggs of Nezara viridula L., Euschistus heros F., Piezodorus guildinii Westwood and Acrosternum aseadum Rolston (Heteroptera: Pentatomidae, in no choice and multiple choice experiments. For all parasitoid species, the results demonstrated the existence of a main host species that maximizes the reproductive success. The competitive interactions among the parasitoid species were investigated in experiments of sequential and simultaneous release of different combinations of parasitoid pairs on the hosts N. viridula, E. heros and A. aseadum. Exploitative competition was observed for egg batches at the genus level (Telenomus vs. Trissolcus and interference competition at the species level (T. basalis vs. T. urichi. Trissolcus urichi was the most aggressive species, interfering with the parasitism of T. basalis. Generally, T. basalis showed an opportunistic behavior trying to parasitise eggs after T. urichi had abandoned the egg batch. The selection of parasitoid species for use in augmentative biological control programs should take into account the diversity of pentatomids present in soybean in addition to the interactions among the different species of parasitoids.

  9. Land-use history affects understorey plant species distributions in a large temperate-forest complex, Denmark

    DEFF Research Database (Denmark)

    Svenning, J.-C.; Baktoft, Karen H.; Balslev, Henrik

    2009-01-01

    In Europe, forests have been strongly influenced by human land-use for millennia. Here, we studied the importance of anthropogenic historical factors as determinants of understorey species distributions in a 967 ha Danish forest complex using 156 randomly placed 100-m2 plots, 15 environmental, 9...... dispersal and a strong literature record as ancient-forest species, were still concentrated in areas that were high forest in 1805. Among the younger forests, there were clear floristic differences between those on reclaimed bogs and those not. Apparently remnant populations of wet-soil plants were still...

  10. Multilocus analysis of divergence and introgression in sympatric and allopatric sibling species of the Lutzomyia longipalpis complex in Brazil.

    Science.gov (United States)

    Araki, Alejandra S; Ferreira, Gabriel E M; Mazzoni, Camila J; Souza, Nataly A; Machado, Ricardo C; Bruno, Rafaela V; Peixoto, Alexandre A

    2013-01-01

    Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Latin America, is a complex of sibling species. In Brazil, a number of very closely related sibling species have been revealed by the analyses of copulation songs, sex pheromones and molecular markers. However, the level of divergence and gene flow between the sibling species remains unclear. Brazilian populations of this vector can be divided in two main groups: one producing Burst-type songs and the Cembrene-1 pheromone and a second more diverse group producing various Pulse song subtypes and different pheromones. We analyzed 21 nuclear loci in two pairs of Brazilian populations: two sympatric populations from the Sobral locality (1S and 2S) in northeastern Brazil and two allopatric populations from the Lapinha and Pancas localities in southeastern Brazil. Pancas and Sobral 2S are populations of the Burst/Cembrene-1 species while Lapinha and Sobral 1S are two putative incipient species producing the same pheromone and similar Pulse song subtypes. The multilocus analysis strongly suggests the occurrence of gene flow during the divergence between the sibling species, with different levels of introgression between loci. Moreover, this differential introgression is asymmetrical, with estimated gene flow being higher in the direction of the Burst/Cembrene-1 species. The results indicate that introgressive hybridization has been a crucial phenomenon in shaping the genome of the L. longipalpis complex. This has possible epidemiological implications and is particularly interesting considering the potential for increased introgression caused by man-made environmental changes and the current trend of leishmaniasis urbanization in Brazil.

  11. Multilocus Analysis of Divergence and Introgression in Sympatric and Allopatric Sibling Species of the Lutzomyia longipalpis Complex in Brazil

    Science.gov (United States)

    Mazzoni, Camila J.; Souza, Nataly A.; Machado, Ricardo C.; Bruno, Rafaela V.

    2013-01-01

    Background Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Latin America, is a complex of sibling species. In Brazil, a number of very closely related sibling species have been revealed by the analyses of copulation songs, sex pheromones and molecular markers. However, the level of divergence and gene flow between the sibling species remains unclear. Brazilian populations of this vector can be divided in two main groups: one producing Burst-type songs and the Cembrene-1 pheromone and a second more diverse group producing various Pulse song subtypes and different pheromones. Methodology/Principal Findings We analyzed 21 nuclear loci in two pairs of Brazilian populations: two sympatric populations from the Sobral locality (1S and 2S) in northeastern Brazil and two allopatric populations from the Lapinha and Pancas localities in southeastern Brazil. Pancas and Sobral 2S are populations of the Burst/Cembrene-1 species while Lapinha and Sobral 1S are two putative incipient species producing the same pheromone and similar Pulse song subtypes. The multilocus analysis strongly suggests the occurrence of gene flow during the divergence between the sibling species, with different levels of introgression between loci. Moreover, this differential introgression is asymmetrical, with estimated gene flow being higher in the direction of the Burst/Cembrene-1 species. Conclusions/Significance The results indicate that introgressive hybridization has been a crucial phenomenon in shaping the genome of the L. longipalpis complex. This has possible epidemiological implications and is particularly interesting considering the potential for increased introgression caused by man-made environmental changes and the current trend of leishmaniasis urbanization in Brazil. PMID:24147172

  12. The rhizosphere microbial community in a multiple parallel mineralization system suppresses the pathogenic fungus Fusarium oxysporum

    Science.gov (United States)

    Fujiwara, Kazuki; Iida, Yuichiro; Iwai, Takashi; Aoyama, Chihiro; Inukai, Ryuya; Ando, Akinori; Ogawa, Jun; Ohnishi, Jun; Terami, Fumihiro; Takano, Masao; Shinohara, Makoto

    2013-01-01

    The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum. PMID:24311557

  13. AKTIVITAS ANTIFUNGI EKSTRAK DAUN KEMANGI (Ocimum americanum L. TERHADAP FUNGI Fusarium oxysporum Schlecht

    Directory of Open Access Journals (Sweden)

    Zainal Berlian

    2016-01-01

    Full Text Available Fusarium oxysporum Schlecht. a parasitic fungus that cause leaf wilt disease in plants. Meanwhile, basil (Ocimum americanum L. is a plant that contains of the active compound in the form of phenols which have antifungal activity. This study aimed to test whether the extract of leaves of basil have antifungal activity againts Fusarium oxysporum Schlecht. and determine the optimum concentration to inhibit the growth of the fungus Fusarium oxysporum Schlecht. Antifungal test is done by using paper disc diffusion method. The study design used was a completely randomized design with 4 treatments and 6 replications. The treatment is K0 (0% w/v, K1 (5% w/v, K2 (10% w/v, and K3 (15% w/v. The results showed that the leaf extract of basil have antifungal activity against Fusarium oxysporum Schlecht. Inhibition zone on K0, K1, K2, and K3 are each 0,0 mm, 1,49 mm, 2,46 mm, and 2,01 mm. The optimum concentration of antifungal activity of extract of basil, namely the K2 concentration (10% w/v. Based on analysis of variance (ANOVA, the concentration of basil leaf extract provides significant differences (p > 0,05 on fungus Fusarium oxysporum Schlecht., where Fcount > Ftable is 4,5 > 3,1.

  14. The rhizosphere microbial community in a multiple parallel mineralization system suppresses the pathogenic fungus Fusarium oxysporum.

    Science.gov (United States)

    Fujiwara, Kazuki; Iida, Yuichiro; Iwai, Takashi; Aoyama, Chihiro; Inukai, Ryuya; Ando, Akinori; Ogawa, Jun; Ohnishi, Jun; Terami, Fumihiro; Takano, Masao; Shinohara, Makoto

    2013-12-01

    The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum. © 2013 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  15. Host-Induced Silencing of Pathogenicity Genes Enhances Resistance to Fusarium oxysporum Wilt in Tomato.

    Science.gov (United States)

    Bharti, Poonam; Jyoti, Poonam; Kapoor, Priya; Sharma, Vandana; Shanmugam, V; Yadav, Sudesh Kumar

    2017-08-01

    This study presents a novel approach of controlling vascular wilt in tomato by RNAi expression directed to pathogenicity genes of Fusarium oxysporum f. sp. lycopersici. Vascular wilt of tomato caused by Fusarium oxysporum f. sp. lycopersici leads to qualitative and quantitative loss of the crop. Limitation in the existing control measures necessitates the development of alternative strategies to increase resistance in the plants against pathogens. Recent findings paved way to RNAi, as a promising method for silencing of pathogenicity genes in fungus and provided effective resistance against fungal pathogens. Here, two important pathogenicity genes FOW2, a Zn(II)2Cys6 family putative transcription regulator, and chsV, a putative myosin motor and a chitin synthase domain, were used for host-induced gene silencing through hairpinRNA cassettes of these genes against Fusarium oxysporum f. sp. lycopersici. HairpinRNAs were assembled in appropriate binary vectors and transformed into tomato plant targeting FOW2 and chsV genes, for two highly pathogenic strains of Fusarium oxysporum viz. TOFOL-IHBT and TOFOL-IVRI. Transgenic tomatoes were analyzed for possible attainment of resistance in transgenic lines against fungal infection. Eight transgenic lines expressing hairpinRNA cassettes showed trivial disease symptoms after 6-8 weeks of infection. Hence, the host-induced posttranscriptional gene silencing of pathogenicity genes in transgenic tomato plants has enhanced their resistance to vascular wilt disease caused by Fusarium oxysporum.

  16. Long noncoding RNAs responsive to Fusarium oxysporum infection in Arabidopsis thaliana.

    Science.gov (United States)

    Zhu, Qian-Hao; Stephen, Stuart; Taylor, Jennifer; Helliwell, Chris A; Wang, Ming-Bo

    2014-01-01

    Short noncoding RNAs have been demonstrated to play important roles in regulation of gene expression and stress responses, but the repertoire and functions of long noncoding RNAs (lncRNAs) remain largely unexplored, particularly in plants. To explore the role of lncRNAs in disease resistance, we used a strand-specific RNA-sequencing approach to identify lncRNAs responsive to Fusarium oxysporum infection in Arabidopsis thaliana. Antisense transcription was found in c. 20% of the annotated A. thaliana genes. Several noncoding natural antisense transcripts responsive to F. oxysporum infection were found in genes implicated in disease defense. While the majority of the novel transcriptionally active regions (TARs) were adjacent to annotated genes and could be an extension of the annotated transcripts, 159 novel intergenic TARs, including 20 F. oxysporum-responsive lncTARs, were identified. Ten F. oxysporum-induced lncTARs were functionally characterized using T-DNA insertion or RNA-interference knockdown lines, and five were demonstrated to be related to disease development. Promoter analysis suggests that some of the F. oxysporum-induced lncTARs are direct targets of transcription factor(s) responsive to pathogen attack. Our results demonstrated that strand-specific RNA sequencing is a powerful tool for uncovering hidden levels of transcriptome and that IncRNAs are important components of the antifungal networks in A. thaliana. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  17. A Clonal Lineage of Fusarium oxysporum Circulates in the Tap Water of Different French Hospitals.

    Science.gov (United States)

    Edel-Hermann, Véronique; Sautour, Marc; Gautheron, Nadine; Laurent, Julie; Aho, Serge; Bonnin, Alain; Sixt, Nathalie; Hartemann, Philippe; Dalle, Frédéric; Steinberg, Christian

    2016-11-01

    Fusarium oxysporum is typically a soilborne fungus but can also be found in aquatic environments. In hospitals, water distribution systems may be reservoirs for the fungi responsible for nosocomial infections. F. oxysporum was previously detected in the water distribution systems of five French hospitals. Sixty-eight isolates from water representative of all hospital units that were previously sampled and characterized by translation elongation factor 1α sequence typing were subjected to microsatellite analysis and full-length ribosomal intergenic spacer (IGS) sequence typing. All but three isolates shared common microsatellite loci and a common two-locus sequence type (ST). This ST has an international geographical distribution in both the water networks of hospitals and among clinical isolates. The ST dominant in water was not detected among 300 isolates of F. oxysporum that originated from surrounding soils. Further characterization of 15 isolates by vegetative compatibility testing allowed us to conclude that a clonal lineage of F. oxysporum circulates in the tap water of the different hospitals. We demonstrated that a clonal lineage of Fusarium oxysporum inhabits the water distribution systems of several French hospitals. This clonal lineage, which appears to be particularly adapted to water networks, represents a potential risk for human infection and raises questions about its worldwide distribution. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  18. Highly Diverse Endophytic and Soil Fusarium oxysporum Populations Associated with Field-Grown Tomato Plants

    Science.gov (United States)

    Demers, Jill E.; Gugino, Beth K.

    2014-01-01

    The diversity and genetic differentiation of populations of Fusarium oxysporum associated with tomato fields, both endophytes obtained from tomato plants and isolates obtained from soil surrounding the sampled plants, were investigated. A total of 609 isolates of F. oxysporum were obtained, 295 isolates from a total of 32 asymptomatic tomato plants in two fields and 314 isolates from eight soil cores sampled from the area surrounding the plants. Included in this total were 112 isolates from the stems of all 32 plants, a niche that has not been previously included in F. oxysporum population genetics studies. Isolates were characterized using the DNA sequence of the translation elongation factor 1α gene. A diverse population of 26 sequence types was found, although two sequence types represented nearly two-thirds of the isolates studied. The sequence types were placed in different phylogenetic clades within F. oxysporum, and endophytic isolates were not monophyletic. Multiple sequence types were found in all plants, with an average of 4.2 per plant. The population compositions differed between the two fields but not between soil samples within each field. A certain degree of differentiation was observed between populations associated with different tomato cultivars, suggesting that the host genotype may affect the composition of plant-associated F. oxysporum populations. No clear patterns of genetic differentiation were observed between endophyte populations and soil populations, suggesting a lack of specialization of endophytic isolates. PMID:25304514

  19. Screenhouse and field persistence of nonpathogenic endophytic Fusarium oxysporum in Musa tissue culture plants.

    Science.gov (United States)

    Paparu, Pamela; Dubois, Thomas; Gold, Clifford S; Niere, Björn; Adipala, Ekwamu; Coyne, Daniel

    2008-04-01

    Two major biotic constraints to highland cooking banana (Musa spp., genome group AAA-EA) production in Uganda are the banana weevil Cosmopolites sordidus and the burrowing nematode Radopholus similis. Endophytic Fusarium oxysporum strains inoculated into tissue culture banana plantlets have shown control of the banana weevil and the nematode. We conducted screenhouse and field experiments to investigate persistence in the roots and rhizome of two endophytic Fusarium oxysporum strains, V2w2 and III4w1, inoculated into tissue-culture banana plantlets of highland cooking banana cultivars Kibuzi and Nabusa. Re-isolation of F. oxysporum showed that endophyte colonization decreased faster from the rhizomes than from the roots of inoculated plants, both in the screenhouse and in the field. Whereas rhizome colonization by F. oxysporum decreased in the screenhouse (4-16 weeks after inoculation), root colonization did not. However, in the field (17-33 weeks after inoculation), a decrease was observed in both rhizome and root colonization. The results show a better persistence in the roots than rhizomes of endophytic F. oxysporum strains V2w2 and III4w1.

  20. Heterologous expression of the Aspergillus nidulans regulatory gene nirA in Fusarium oxysporum.

    Science.gov (United States)

    Daboussi, M J; Langin, T; Deschamps, F; Brygoo, Y; Scazzocchio, C; Burger, G

    1991-12-20

    We have isolated strains of Fusarium oxysporum carrying mutations conferring a phenotype characteristic of a loss of function in the regulatory gene of nitrate assimilation (nirA in Aspergillus nidulans, nit-4 in Neurospora crassa). One of these nir- mutants was successfully transformed with a plasmid containing the nirA gene of A. nidulans. The nitrate reductase of the transformants is still inducible, although the maximum activity is lower than in the wild type. Single and multiple integration events were found, as well as a strict correlation between the presence of the nirA gene and the Nir+ phenotype of the F. oxysporum transformants. We also investigated how the A. nidulans structural gene (niaD) is regulated in F. oxysporum. Enzyme assays and Northern experiments show that the niaD gene is subject to nitrate induction and that it responds to nitrogen metabolite repression in a F. oxysporum genetic background. This indicates that both the mechanisms of specific induction, mediated by a gene product isofunctional to nirA, and nitrogen metabolite repression, presumably mediated by a gene product isofunctional to the homologous gene of A. nidulans, are operative in F. oxysporum.

  1. Molecular characterization of a subtilase from the vascular wilt fungus Fusarium oxysporum.

    Science.gov (United States)

    Di Pietro, A; Huertas-González, M D; Gutierrez-Corona, J F; Martínez-Cadena, G; Méglecz, E; Roncero, M I

    2001-05-01

    The gene prt1 was isolated from the tomato vascular wilt fungus Fusarium oxysporum f. sp. lycopersici, whose predicted amino acid sequence shows significant homology with subtilisin-like fungal proteinases. Prt1 is a single-copy gene, and its structure is highly conserved among different formae speciales of F. oxysporum. Prt1 is expressed constitutively at low levels during growth on different carbon and nitrogen sources and strongly induced in medium containing collagen and glucose. As shown by reverse transcription-polymerase chain reaction and fluorescence microscopy of F. oxysporum strains carrying a prt1-promoter-green fluorescent protein fusion, prt1 is expressed at low levels during the entire cycle of infection on tomato plants. F. oxysporum strains transformed with an expression vector containing the prt1 coding region fused to the inducible endopolygalacturonase pg1 gene promoter and grown under promoter-inducing conditions secreted high levels of extracellular subtilase activity that resolved into a single peak of pI 4.0 upon isoelectric focusing. The active fraction produced two clearing bands of 29 and 32 kDa in sodium dodecyl sulfate gels containing gelatin. Targeted inactivation of prt1 in F. oxysporum f. sp. lycopersici had no detectable effect on mycelial growth, sporulation, and pathogenicity on tomato plants.

  2. Epiphytic diatoms in lotic and lentic waters - diversity and representation of species complexes

    Czech Academy of Sciences Publication Activity Database

    Kollár, J.; Fránková, Markéta; Hašler, P.; Letáková, M.; Poulíčková, A.

    2015-01-01

    Roč. 15, č. 2 (2015), s. 259-271 ISSN 1802-5439 Institutional support: RVO:67985939 Keywords : diatoms * epiphyton * species comlexes * lotic and lentic waters Subject RIV: EF - Botanics Impact factor: 2.026, year: 2015

  3. The 'species complex' issue in clinically relevant fungi : A case study in Scedosporium apiospermum

    NARCIS (Netherlands)

    Chen, Min; Zeng, Jingsi; De Hoog, G Sybren; Stielow, Benjamin; Gerrits Van Den Ende, A H G; Liao, Wanqing; Lackner, Michaela

    The genus Scedosporium currently comprises six species, Scedosporium apiospermum, Scedosporium boydii, Pseudallescheria angusta, Scedosporium minutisporum, Scedosporium dehoogii, and Scedosporium aurantiacum, most of which can be distinguished with the primary fungal DNA barcode, the ITS1/2 region

  4. Endophytic control of Cosmopolites sordidus and Radopholus similis using Fusarium oxysporum V5w2 in tissue culture banana

    NARCIS (Netherlands)

    Ochieno, D.M.W.

    2010-01-01

    Banana plants are being inoculated with Fusarium oxysporum V5w2 and Beauveria bassiana G41 for endophytic control of pests. The effects of F. oxysporum V5w2 and B. bassiana G41, soil sterility, fertilizer, and mulching, on Cosmopolites sordidus and Radopholus similis in banana plants, are

  5. Complex phylogenetic placement of ilex species (aquifoliaceae): a case study of molecular phylogeny

    International Nuclear Information System (INIS)

    Yi, F.; Sun, L.; Xiao, P.G.; Hao, D.C.

    2017-01-01

    To investigate the phylogenetic relationships among Ilex species distributed in China, we analyzed two alignments including 4,698 characters corresponding to six plastid sequences (matK, rbcL, atpB-rbcL, trnL-F, psbA-trnH, and rpl32-trnL) and 1,748 characters corresponding to two nuclear sequences (ITS and nepGS). Using different partitioning strategies and approaches (i.e., Bayesian inference, maximum likelihood, and maximum parsimony) for phylogeny reconstruction, different topologies and clade supports were determined. A total of 18 Ilex species was divided into two major groups (group I and II) in both plastid and nuclear phylogenies with some incongruences. Potential hybridization events may account, in part, for those phylogenetic uncertainties. The analyses, together with previously identified sequences, indicated that all 18 species were recovered within Eurasia or Asia/North America groups based on plastid data. Meanwhile, the species in group II in the nuclear phylogeny were placed in the Aquifolium clade, as inferred from traditional classification, whereas the species in group I belonged to several other clades. The divergence time of most of the 18 Ilex species was estimated to be not more than 10 million years ago. Based on the results of this study, we concluded that paleogeographical events and past climate changes during the same period might have played important roles in these diversifications. (author)

  6. New dereplication method applied to NMR-Based metabolomics on different fusarium species isolated from Rhizosphere of Senna spectabilis

    International Nuclear Information System (INIS)

    Selegato, Denise M.; Castro-Gamboa, Ian; Freire, Rafael T.; Tannús, Alberto

    2016-01-01

    The search for new sources of natural products steadily increased the use of bioinformatics tools that enabled efficient analysis of complex matrices. In this context, dereplication methods emerged as a fast way of identifying known compounds, accelerating the identification of bioactive chemotypes. Although 1 H NMR is widely used as an analytical technique, few studies have been reported using it as a dereplication tool, primarily because of the spectral complexity. This work aims to create a new computational method that analyses 1 H NMR data from Fusarium solani and F. oxysporum isolated from Senna spectabilis' srhizosphere through principal component analysis (PCA). The algorithm uses loading values to select important peaks that distinguish both species in PCA, allowing compound dereplication, even in highly similar profiles. As a result, the method, associated with other NMR experiments and information from an in-house Fusarium's metabolite library was able to distinguish different mycotoxins produced by both fungi, identifying fusaric acid and beauvericin for F. oxysporum and the depsipeptide HA23 from F. solani. (author)

  7. New dereplication method applied to NMR-Based metabolomics on different fusarium species isolated from Rhizosphere of Senna spectabilis

    Energy Technology Data Exchange (ETDEWEB)

    Selegato, Denise M.; Castro-Gamboa, Ian, E-mail: ian.castro@gmail.com [Universidade Estadual Paulista Júlio de Mesquita Filho (NuBBE/UNESP), Araraquara, SP (Brazil). Núcleo de Bioensaios, Biossíntese e Ecofisiologia de Produtos Naturais; Freire, Rafael T.; Tannús, Alberto [Universidade de São Paulo (CIERMag/USP), São Carlos, SP (Brazil). Centro de Imagens e Espectroscopia in Vivo por Ressonância Magnética

    2016-07-01

    The search for new sources of natural products steadily increased the use of bioinformatics tools that enabled efficient analysis of complex matrices. In this context, dereplication methods emerged as a fast way of identifying known compounds, accelerating the identification of bioactive chemotypes. Although {sup 1}H NMR is widely used as an analytical technique, few studies have been reported using it as a dereplication tool, primarily because of the spectral complexity. This work aims to create a new computational method that analyses {sup 1}H NMR data from Fusarium solani and F. oxysporum isolated from Senna spectabilis' srhizosphere through principal component analysis (PCA). The algorithm uses loading values to select important peaks that distinguish both species in PCA, allowing compound dereplication, even in highly similar profiles. As a result, the method, associated with other NMR experiments and information from an in-house Fusarium's metabolite library was able to distinguish different mycotoxins produced by both fungi, identifying fusaric acid and beauvericin for F. oxysporum and the depsipeptide HA23 from F. solani. (author)

  8. Towards Plant Species Identification in Complex Samples: A Bioinformatics Pipeline for the Identification of Novel Nuclear Barcode Candidates.

    Directory of Open Access Journals (Sweden)

    Alexandre Angers-Loustau

    Full Text Available Monitoring of the food chain to fight fraud and protect consumer health relies on the availability of methods to correctly identify the species present in samples, for which DNA barcoding is a promising candidate. The nuclear genome is a rich potential source of barcode targets, but has been relatively unexploited until now. Here, we show the development and use of a bioinformatics pipeline that processes available genome sequences to automatically screen large numbers of input candidates, identifies novel nuclear barcode targets and designs associated primer pairs, according to a specific set of requirements. We applied this pipeline to identify novel barcodes for plant species, a kingdom for which the currently available solutions are known to be insufficient. We tested one of the identified primer pairs and show its capability to correctly identify the plant species in simple and complex samples, validating the output of our approach.

  9. Colony geometry and structural complexity of the endangered species Acropora cervicornis partly explains the structure of their associated fish assemblage.

    Science.gov (United States)

    Agudo-Adriani, Esteban A; Cappelletto, Jose; Cavada-Blanco, Francoise; Croquer, Aldo

    2016-01-01

    In the past decade, significant efforts have been made to describe fish-habitat associations. However, most studies have oversimplified actual connections between fish assemblages and their habitats by using univariate correlations. The purpose of this study was to identify the features of habitat forming corals that facilitate and influences assemblages of associated species such as fishes. For this we developed three-dimensional models of colonies of Acropora cervicornis to estimate geometry (length and height), structural complexity (i.e., volume, density of branches, etc.) and biological features of the colonies (i.e., live coral tissue, algae). We then correlated these colony characteristics with the associated fish assemblage using multivariate analyses. We found that geometry and complexity were better predictors of the structure of fish community, compared to other variables such as percentage of live coral tissue or algae. Combined, the geometry of each colony explained 40% of the variability of the fish assemblage structure associated with this coral species; 61% of the abundance and 69% of fish richness, respectively. Our study shows that three-dimensional reconstructions of discrete colonies of Acropora cervicornis provides a useful description of the colonial structural complexity and may explain a great deal of the variance in the structure of the associated coral reef fish community. This demonstration of the strongly trait-dependent ecosystem role of this threatened species has important implications for restoration and conservation efforts.

  10. Colony geometry and structural complexity of the endangered species Acropora cervicornis partly explains the structure of their associated fish assemblage

    Directory of Open Access Journals (Sweden)

    Esteban A. Agudo-Adriani

    2016-04-01

    Full Text Available In the past decade, significant efforts have been made to describe fish-habitat associations. However, most studies have oversimplified actual connections between fish assemblages and their habitats by using univariate correlations. The purpose of this study was to identify the features of habitat forming corals that facilitate and influences assemblages of associated species such as fishes. For this we developed three-dimensional models of colonies of Acropora cervicornis to estimate geometry (length and height, structural complexity (i.e., volume, density of branches, etc. and biological features of the colonies (i.e., live coral tissue, algae. We then correlated these colony characteristics with the associated fish assemblage using multivariate analyses. We found that geometry and complexity were better predictors of the structure of fish community, compared to other variables such as percentage of live coral tissue or algae. Combined, the geometry of each colony explained 40% of the variability of the fish assemblage structure associated with this coral species; 61% of the abundance and 69% of fish richness, respectively. Our study shows that three-dimensional reconstructions of discrete colonies of Acropora cervicornis provides a useful description of the colonial structural complexity and may explain a great deal of the variance in the structure of the associated coral reef fish community. This demonstration of the strongly trait-dependent ecosystem role of this threatened species has important implications for restoration and conservation efforts.

  11. A distinct alleles and genetic recombination of pmrCAB operon in species of Acinetobacter baumannii complex isolates.

    Science.gov (United States)

    Kim, Dae Hun; Ko, Kwan Soo

    2015-07-01

    To investigate pmrCAB sequence divergence in 5 species of Acinetobacter baumannii complex, a total of 80 isolates from a Korean hospital were explored. We evaluated nucleotide and amino acid polymorphisms of pmrCAB operon, and phylogenetic trees were constructed for each gene of prmCAB operon. Colistin and polymyxin B susceptibility was determined for all isolates, and multilocus sequence typing was also performed for A. baumannii isolates. Our results showed that each species of A. baumannii complex has divergent pmrCAB operon sequences. We identified a distinct pmrCAB allele allied with Acinetobacter nosocomialis in gene trees. Different grouping in each gene tree suggests sporadic recombination or emergence of pmrCAB genes among Acinetobacter species. Sequence polymorphisms among Acinetobacter species might not be associated with colistin resistance. We revealed that a distinct pmrCAB allele may be widespread across the continents such as North America and Asia and that sporadic genetic recombination or emergence of pmrCAB genes might occur. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. A new Eastern Central Atlantic skate Raja parva sp. nov. (Rajoidei: Rajidae) belonging to the Raja miraletus species complex.

    Science.gov (United States)

    Last, Peter R; Séret, Bernard

    2016-08-05

    An investigation of combined CO1 and NADH2 data for rajid skates referable to Raja miraletus provided evidence that populations ranging from southern Africa to the North-East Atlantic and Mediterranean Sea, once considered to represent a cline, belong to a species complex consisting of at least four valid species. Raja miraletus appears to be confined to the Mediterranean Sea, and the North-East Atlantic from the Bay of Biscay south to Morocco and Madeira. The southernmost species, referable to the resurrected Raja ocellifera, occurs off southern Africa, off Namibia and from False Bay to Durban (South Africa). Two species occur off tropical West Africa, including Raja parva sp. nov. (Senegal, Liberia and Angola but is probably more widespread within the region), and another unidentified species needing further investigation. Raja cf. miraletus, confirmed from Mauritania and Senegal, appears to be a larger skate with a broader disc, more broadly pointed snout, larger spiracles, and a slightly longer and broader tail. Raja parva sp. nov. differs from nominal members of the complex in having an unusually long procaudal tail (exceeding 22% TL), as well as a combination of other external characters. Past investigators observed morphological and anatomical differences between these forms but these were thought to be due to intraspecific variability. They postulated that an upwelling at Cape Blanco (21°N) may have isolated the Mediterranean form (R. miraletus) from Mauritania-Senegal form (now known to be two species). Similarly, the Benguela Current and upwelling off Cape Frio (18°S) were thought to be responsible for separating the Angolan form (R. parva) and South African form (R. ocellifera).

  13. Identification and characterization of multiple emissive species in aggregated minor antenna complexes

    Czech Academy of Sciences Publication Activity Database

    Wahadoszamen, M.; Belgio, Erica; Rahman, M.A.; Ara, A.M.; Ruban, A.V.; van Grondelle, R.

    2016-01-01

    Roč. 1857, č. 12 (2016), s. 1917-1924 ISSN 0005-2728 Institutional support: RVO:61388971 Keywords : Light harvesting * Minor antenna complexes * Photoprotective energy dissipation Subject RIV: EE - Microbiology, Virology Impact factor: 4.932, year: 2016

  14. Palladium(0) alkyne complexes as active species: A DFT-investigation

    DEFF Research Database (Denmark)

    Ahlquist, Mårten Sten Gösta; Fabrizi, Giancarlo; Cacchi, Sandro

    2005-01-01

    Alkynes have been found to be excellent ligands for Pd(0); the stability of a range of alkyne-Pd(0) complexes, and their reactivity in oxidative addition, have been investigated by DFT methods.......Alkynes have been found to be excellent ligands for Pd(0); the stability of a range of alkyne-Pd(0) complexes, and their reactivity in oxidative addition, have been investigated by DFT methods....

  15. Penghambatan Fusarium oxysporum oleh Kultur Filtrat Bakteri Endofit dari Tanaman Kedelai secara in Vitro

    Directory of Open Access Journals (Sweden)

    Novi Malinda

    2016-02-01

    Full Text Available Seed borne pathogen play an important role as source of inoculum for disease incidence in the field and it becomes a major constraint in certified seed production.  Research was conducted to isolate potential endophytic bacteria from soybean plants and evaluate its culture filtrate for inhibition effect of seedborne fungi on soybean seed, i.e. Fusarium oxysporum.  The result showed that out of forty eight endophytic bacteria isolates that were nonpathogenic, there were three potential isolates that can inhibit the growth of F. oxysporum, i.e.  EDA 3, EBA 6, and EBA 7 with percent inhibition of 60.14%, 57.69%, and 57.08%, respectively. The filtrate culture of EBA 7 showed the highest inhibition (34.88% by in vitro test. Therefore, those three isolates of endophytic bacteria might be used as biocontrol agent to inhibit the growth of F. oxysporum.

  16. Interbreeding and DNA analysis of sibling species within the Bactrocera dorsalis complex

    International Nuclear Information System (INIS)

    Tan, Keng-Hong

    2003-01-01

    Bactrocera dorsalis and B. papayae interbreed readily and produce viable offspring under laboratory conditions. Under laboratory observation of B. carambolae and B. papayae interbreeding, the average number of eggs laid by hybrid females was lower than that of B. papayae females but higher than that of B. carambolae females of intra-specific crosses. For inter- and intra-specific mating, the copulatory period is dependent on the female species involved - female B. carambolae copulates significantly longer than that of B. papayae female. Aedeagal and aculeus length of hybrids are intermediate between those of their respective parental species. Hybrid males have one to four sex pheromonal components after consumption of methyl eugenol; 2-6% of them possess a combination of endogenous pheromonal components specific to B. carambolae and components derived from methyl eugenol typical of B. papayae. Based on the latter, four wild males captured from different parts of Peninsular Malaysia possessed combination of the sex pheromonal components. DNA analysis using PCR techniques was very useful in differentiating pest species. Using AFLP polymorphism of amplified DNA fragment plus calculated Nei's genetic distance showed that natural hybrid of B. carambolae and B. papayae was closer to B. dorsalis than to the parental species. Using exon primed, intron crossing PCR, one of the three alleles of actin gene intron of B. dorsalis has identical DNA sequence to one of three allelic introns of the same gene in B. papayae which suggests that the two species are not distinct genetic species. A Hobo-like transposon element was detected in a population from Penang Island, while in a population from the mainland of Peninsular Malaysia, a mariner-like transposon element was detected. (author)

  17. The mate recognition protein gene mediates reproductive isolation and speciation in the Brachionus plicatilis cryptic species complex.

    Science.gov (United States)

    Gribble, Kristin E; Mark Welch, David B

    2012-08-01

    Chemically mediated prezygotic barriers to reproduction likely play an important role in speciation. In facultatively sexual monogonont rotifers from the Brachionus plicatilis cryptic species complex, mate recognition of females by males is mediated by the Mate Recognition Protein (MRP), a globular glycoprotein on the surface of females, encoded by the mmr-b gene family. In this study, we sequenced mmr-b copies from 27 isolates representing 11 phylotypes of the B. plicatilis species complex, examined the mode of evolution and selection of mmr-b, and determined the relationship between mmr-b genetic distance and mate recognition among isolates. Isolates of the B. plicatilis species complex have 1-4 copies of mmr-b, each composed of 2-9 nearly identical tandem repeats. The repeats within a gene copy are generally more similar than are gene copies among phylotypes, suggesting concerted evolution. Compared to housekeeping genes from the same isolates, mmr-b has accumulated only half as many synonymous differences but twice as many non-synonymous differences. Most of the amino acid differences between repeats appear to occur on the outer face of the protein, and these often result in changes in predicted patterns of phosphorylation. However, we found no evidence of positive selection driving these differences. Isolates with the most divergent copies were unable to mate with other isolates and rarely self-crossed. Overall the degree of mate recognition was significantly correlated with the genetic distance of mmr-b. Discrimination of compatible mates in the B. plicatilis species complex is determined by proteins encoded by closely related copies of a single gene, mmr-b. While concerted evolution of the tandem repeats in mmr-b may function to maintain identity, it can also lead to the rapid spread of a mutation through all copies in the genome and thus to reproductive isolation. The mmr-b gene is evolving rapidly, and novel alleles may be maintained and increase in

  18. The mate recognition protein gene mediates reproductive isolation and speciation in the Brachionus plicatilis cryptic species complex

    Directory of Open Access Journals (Sweden)

    Gribble Kristin E

    2012-08-01

    Full Text Available Abstract Background Chemically mediated prezygotic barriers to reproduction likely play an important role in speciation. In facultatively sexual monogonont rotifers from the Brachionus plicatilis cryptic species complex, mate recognition of females by males is mediated by the Mate Recognition Protein (MRP, a globular glycoprotein on the surface of females, encoded by the mmr-b gene family. In this study, we sequenced mmr-b copies from 27 isolates representing 11 phylotypes of the B. plicatilis species complex, examined the mode of evolution and selection of mmr-b, and determined the relationship between mmr-b genetic distance and mate recognition among isolates. Results Isolates of the B. plicatilis species complex have 1–4 copies of mmr-b, each composed of 2–9 nearly identical tandem repeats. The repeats within a gene copy are generally more similar than are gene copies among phylotypes, suggesting concerted evolution. Compared to housekeeping genes from the same isolates, mmr-b has accumulated only half as many synonymous differences but twice as many non-synonymous differences. Most of the amino acid differences between repeats appear to occur on the outer face of the protein, and these often result in changes in predicted patterns of phosphorylation. However, we found no evidence of positive selection driving these differences. Isolates with the most divergent copies were unable to mate with other isolates and rarely self-crossed. Overall the degree of mate recognition was significantly correlated with the genetic distance of mmr-b. Conclusions Discrimination of compatible mates in the B. plicatilis species complex is determined by proteins encoded by closely related copies of a single gene, mmr-b. While concerted evolution of the tandem repeats in mmr-b may function to maintain identity, it can also lead to the rapid spread of a mutation through all copies in the genome and thus to reproductive isolation. The mmr-b gene is evolving

  19. Transcriptome analysis of Pseudostellaria heterophylla in response to the infection of pathogenic Fusarium oxysporum.

    Science.gov (United States)

    Qin, Xianjin; Wu, Hongmiao; Chen, Jun; Wu, Linkun; Lin, Sheng; Khan, Muhammad Umar; Boorboori, Mohammad Reza; Lin, Wenxiong

    2017-09-18

    Pseudostellaria heterophylla (P. heterophylla), a herbaceous perennial, belongs to Caryophyllaceae family and is one of the Chinese herbal medicine with high pharmacodynamic value. It can be used to treat the spleen deficiency, anorexia, weakness after illness and spontaneous perspiration symptoms. Our previous study found that consecutive monoculture of Pseudostellaria heterophylla could lead to the deterioration of the rhizosphere microenvironment. The specialized forms of pathogenic fungus Fusarium oxysporum f.Sp. heterophylla (F. oxysporum) in rhizosphere soils of P. heterophylla plays an important role in the consecutive monoculture of P. heterophylla. In this study, F. oxysporum was used to infect the tissue culture plantlets of P. heterophylla to study the responding process at three different infection stages by using RNA-sequencing. We obtained 127,725 transcripts and 47,655 distinct unigenes by de novo assembly and obtained annotated information in details for 25,882 unigenes. The Kyoto Encyclopedia of Genes and Genomes pathway analysis and the real-time quantitative PCR results suggest that the calcium signal system and WRKY transcription factor in the plant-pathogen interaction pathway may play an important role in the response process, and all of the WRKY transcription factor genes were divided into three different types. Moreover, we also found that the stimulation of F. oxysporum may result in the accumulation of some phenolics in the plantlets and the programmed cell death of the plantlets. This study has partly revealed the possible molecular mechanism of the population explosion of F. oxysporum in rhizosphere soils and signal response process, which can be helpful in unraveling the role of F. oxysporum in consecutive monoculture problems of P. heterophylla.

  20. Genotyping species of the Sporothrix schenckii complex by PCR-RFLP of calmodulin

    NARCIS (Netherlands)

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

    Sporotrichosis is one of the most common subcutaneous mycosis in Latin America and is caused by 4 pathogenic thermodimorphic fungi in the genus Sporothrix. From both therapeutic and epidemiological perspectives, it is essential to identify the causative agents down to the species level. Traditional

  1. Stem cankers on sunflower (Helianthus annuus) in Australia reveal a complex of pathogenic Diaporthe (Phomopsis) species

    NARCIS (Netherlands)

    Thompson, S.M.; Tan, Y.P.; Young, A.J.; Neate, S.M.; Aitken, E.A.B.; Shivas, R.G.

    2012-01-01

    The identification of Diaporthe (anamorph Phomopsis) species associated with stem canker of sunflower (Helianthus annuus) in Australia was studied using morphology, DNA sequence analysis and pathology. Phylogenetic analysis revealed three clades that did not correspond with known taxa, and these are

  2. Intraspecific variation of cuticular hydrocarbon profiles in the Anastrepha fraterculus (Diptera: Tephritidae) species complex

    Czech Academy of Sciences Publication Activity Database

    Vaníčková, Lucie; Břízová, Radka; Mendonca, A. L.; Pompeiano, A.; do Nascimento, R. R.

    2015-01-01

    Roč. 139, č. 9 (2015), s. 679-689 ISSN 0931-2048 Institutional support: RVO:61388963 Keywords : chemotaxonomy * GCxGC/TOFMS * multiple factorial analyses * putative species * South American fruit fly Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.517, year: 2015

  3. Pennisetum section Brevivalvula in West Africa : morphological and genetic variation in an agamic species complex

    NARCIS (Netherlands)

    Schmelzer, G.H.

    1998-01-01

    Section Brevivalvula is one of five sections in the large tropical grass genus Pennisetum . It belongs to the tertiary genepool of P. glaucum (L.) R. Br., pearl millet, and consists of six morphological species: P.

  4. Current knowledge of the species complex Anastrepha fraterculus (Diptera, Tephritidae) in Brazil

    Czech Academy of Sciences Publication Activity Database

    Vaníčková, Lucie; Hernández-Ortiz, V.; Bravo, I. S. J.; Dias, V.; Roriz, A. K. P.; Laumann, R. A.; Mendonca, A. L.; Paranhos, B. A. J.; do Nascimento, R. R.

    -, č. 540 (2015), s. 211-237 ISSN 1313-2989 Institutional support: RVO:61388963 Keywords : South American fruit fly * cryptic species * taxonomy * sexual behavior * chemical communication Subject RIV: EG - Zoology Impact factor: 0.938, year: 2015 http://zookeys.pensoft.net/articles.php?id=6228

  5. The complex evolutionary history and phylogeography of Caridina typus (Crustacea: Decapoda): long-distance dispersal and cryptic allopatric species.

    Science.gov (United States)

    Bernardes, Samuel C; Pepato, Almir R; von Rintelen, Thomas; von Rintelen, Kristina; Page, Timothy J; Freitag, Hendrik; de Bruyn, Mark

    2017-08-22

    The evolutionary history of the old, diverse freshwater shrimp genus Caridina is still poorly understood, despite its vast distribution - from Africa to Polynesia. Here, we used nuclear and mitochondrial DNA to infer the phylogeographic and evolutionary history of C. typus, which is one of only four species distributed across the entire range of the genus. Despite this species' potential for high levels of gene flow, questions have been raised regarding its phylogeographic structure and taxonomic status. We identified three distinct lineages that likely diverged in the Miocene. Molecular dating and ancestral range reconstructions are congruent with C. typus' early dispersal to Africa, possibly mediated by the Miocene Indian Ocean Equatorial Jet, followed by back dispersal to Australasia after the Jet's closure. Furthermore, several different species delimitation methods indicate each lineage represents a distinct (cryptic) species, contradicting current morphospecies delimitation of a single C. typus taxon. The evolutionary history of C. typus lineages is complex, in which ancient oceanic current systems and (currently unrecognised) speciation events preceded secondary sympatry of these cryptic species.

  6. First discovery of Quercus-feeding Nepticulidae (Lepidoptera) in South America, with description of new species and designation of the S. nigriverticella complex in the S. saginella group.

    Science.gov (United States)

    Remeikis, Andrius; Stonis, Jonas R

    2015-12-11

    We describe three new species: Stigmella crassifoliae Remeikis & Stonis, sp. nov. (a leaf-miner on Quercus crassifolia and Q. crispipilis from the highlands of Guatemala), S. robleae Remeikis & Stonis, sp. nov., and S. humboldti Remeikis & Stonis, sp. nov. (leaf-miners on Quercus humboldtii from the Colombian Andes). No Quercus-feeding Nepticulidae species were previously known from South America. All new species are illustrated with photographs of the leaf-mines, cocoons, adults, and genitalia. In the S. saginella species group, for the species possessing in male genitalia M-shaped gnathos with caudal processes closely juxtaposed and phallus without cornuti, a new species complex (the S. nigriverticella complex) is defined. We also provide a pictorial key to the species of the new complex.

  7. Mechanistic aspects of biosynthesis of silver nanoparticles by several Fusarium oxysporum strains

    Directory of Open Access Journals (Sweden)

    De Souza Gabriel IH

    2005-07-01

    Full Text Available Abstract Extracellular production of metal nanoparticles by several strains of the fungus Fusarium oxysporum was carried out. It was found that aqueous silver ions when exposed to several Fusarium oxysporum strains are reduced in solution, thereby leading to the formation of silver hydrosol. The silver nanoparticles were in the range of 20–50 nm in dimensions. The reduction of the metal ions occurs by a nitrate-dependent reductase and a shuttle quinone extracellular process. The potentialities of this nanotechnological design based in fugal biosynthesis of nanoparticles for several technical applications are important, including their high potential as antibacterial material.

  8. Estudio del antagonismo de algunas especies de trichoderma sobre fusarium oxysporum y rhizoctonia solani

    OpenAIRE

    Elias, Ricardo; Arcos, Omar; Arbelaez, Germán

    2011-01-01

    En este trabajo se estudió el antagonismo de algunos aislamientos del hongo Trichoderma obtenidos de suelos colornbianos en el control de Fusarium oxysporum y Rhizoctonia solani. En los ensayos "in vitre" se observó un marcado antagonismo entre las colonias de los aislamientos de Trichoderma sobre R. sotsni, con una reducción apreciabledel tamaño de la colonia y un antaqonismo menor sobre F. oxysporum. En los ensayos de parasitismo a nivel microscópico, se observó una gran interacción entre a...

  9. Components of the ligninolytic system of Fusarium oxysporum and Trichoderma atroviride

    Energy Technology Data Exchange (ETDEWEB)

    Moenkemann, H.; Hoelker, U.; Hoefer, M. [Universitaet Bonn, Bonn (Germany). Botanisches Institut

    1997-11-01

    The ligninolytic system in the two deuteromycetous fungi Fusarium oxysporum and Trichoderma atroviride, which are able to solubilize low-rank coal, has been proved to have several components. Analysis of the chromosomal DNA of these fungi revealed distinct bands with probes coding for three ligninase isoenzymes, glyoxal oxidase and arylalcohol dehydrogenase of the basidiomycete Phanerochaete chrysosporium. These data constitute a strong indication for the existence in F. oxysporum and T. atroviride of a ligninolytic system comparable to that in P. chrysosporium that may be involved in the process of coal solubilization. 11 refs., 3 figs.

  10. Identification of a New Mullet Species Complex Based on an Integrative Molecular and Cytogenetic Investigation of Mugil hospes (Mugilidae: Mugiliformes).

    Science.gov (United States)

    Nirchio, Mauro; Paim, Fabilene G; Milana, Valentina; Rossi, Anna R; Oliveira, Claudio

    2018-01-01

    Mullets are very common fishes included in the family Mugilidae, (Mugiliformes), which are characterized by both a remarkably uniform external morphology and internal anatomy. Recently, within this family, different species complexes were molecularly identified within Mugil , a genus which is characterized by lineages that sometimes show very different karyotypes. Here we report the results of cytogenetic and molecular analyses conducted on Mugil hospes , commonly known as the hospe mullet, from Ecuador. The study aims to verify whether the original described species from the Pacific Ocean corresponds to that identified in the Atlantic Ocean, and to identify species-specific chromosome markers that can add new comparative data about Mugilidae karyotype evolution. The karyotype of M. hospes from Ecuador is composed of 48 acrocentric chromosomes and shows two active nucleolar organizer regions (NORs). In situ hybridization, using different types of repetitive sequences (rDNAs, U1 snDNA, telomeric repeats) as probes, identified species-specific chromosome markers that have been compared with those of other species of the genus Mugil . Cytochrome c oxidase subunit I (COI) sequence analysis shows only 92-93% similarity with sequences previously deposited under this species name in GenBank, all of which were from the Atlantic Ocean. Phylogenetic reconstructions indicate the presence of three well-supported hospe mullet lineages whose molecular divergence is compatible with the presence of distinct species. Indeed, the first lineage includes samples from Ecuador, whereas the other two lineages include the Atlantic samples and correspond to M. brevirostris from Brazil and Mugil sp. R from Belize/Venezuela. Results here provided reiterate the pivotal importance of an integrative molecular and cytogenetic approach in the reconstruction of the relationships within Mugilidae.

  11. Identification of a New Mullet Species Complex Based on an Integrative Molecular and Cytogenetic Investigation of Mugil hospes (Mugilidae: Mugiliformes

    Directory of Open Access Journals (Sweden)

    Mauro Nirchio

    2018-02-01

    Full Text Available Mullets are very common fishes included in the family Mugilidae, (Mugiliformes, which are characterized by both a remarkably uniform external morphology and internal anatomy. Recently, within this family, different species complexes were molecularly identified within Mugil, a genus which is characterized by lineages that sometimes show very different karyotypes. Here we report the results of cytogenetic and molecular analyses conducted on Mugil hospes, commonly known as the hospe mullet, from Ecuador. The study aims to verify whether the original described species from the Pacific Ocean corresponds to that identified in the Atlantic Ocean, and to identify species-specific chromosome markers that can add new comparative data about Mugilidae karyotype evolution. The karyotype of M. hospes from Ecuador is composed of 48 acrocentric chromosomes and shows two active nucleolar organizer regions (NORs. In situ hybridization, using different types of repetitive sequences (rDNAs, U1 snDNA, telomeric repeats as probes, identified species-specific chromosome markers that have been compared with those of other species of the genus Mugil. Cytochrome c oxidase subunit I (COI sequence analysis shows only 92–93% similarity with sequences previously deposited under this species name in GenBank, all of which were from the Atlantic Ocean. Phylogenetic reconstructions indicate the presence of three well-supported hospe mullet lineages whose molecular divergence is compatible with the presence of distinct species. Indeed, the first lineage includes samples from Ecuador, whereas the other two lineages include the Atlantic samples and correspond to M. brevirostris from Brazil and Mugil sp. R from Belize/Venezuela. Results here provided reiterate the pivotal importance of an integrative molecular and cytogenetic approach in the reconstruction of the relationships within Mugilidae.

  12. Two new species of the Liolaemus elongatus-kriegi complex (Iguania, Liolaemidae) from Andean highlands of southern Chile

    Science.gov (United States)

    Troncoso-Palacios, Jaime; Díaz, Hugo A.; Esquerré, Damien; Urra, Felix A.

    2015-01-01

    Abstract The elongatus-kriegi complex is one of the most diverse clades of the Liolaemus (sensu stricto) subgenus of lizards. There are currently 29 species recognized in this group distributed between Chile and Argentina. Based on molecular evidence, there seem to be five main clades nested within this complex: the elongatus, leopardinus, kriegi, petrophilus and punmahuida clades. Liolaemus buergeri and Liolaemus kriegi, both of the kriegi clade, were believed to inhabit the surroundings of the Laja Lagoon, in the Biobío Region of Chile. Moreover, this Chilean population of Liolaemus kriegi was recently recognized as an undescribed taxon called “Liolaemus sp. A” based on molecular phylogenetics. In this work, we studied these two populations of the Laja Lagoon and provided the morphological diagnosis to describe them as two new species: Liolaemus scorialis sp. n. and Liolaemus zabalai sp. n., previously considered Liolaemus buergeri and “Liolaemus kriegi/Liolaemus sp. A” respectively. Additionally, we identified another population of Liolaemus scorialis in the vicinity of La Mula Lagoon in the Araucanía Region of Chile. Liolaemus scorialis differs from almost all of the species of the elongatus-kriegi complex by its considerably smaller size. Nevertheless, without molecular data we cannot assign it to any particular subclade. Liolaemus zabalai belongs to the kriegi clade based on published molecular phylogenies. Finally, we provide some natural history data on both species and we document for the first time the presence of Liolaemus neuquensis in Chile from a museum specimen from La Mula Lagoon. PMID:25987873

  13. Inferring selection in the Anopheles gambiae species complex: an example from immune-related serine protease inhibitors

    Directory of Open Access Journals (Sweden)

    Little Tom J

    2009-06-01

    Full Text Available Abstract Background Mosquitoes of the Anopheles gambiae species complex are the primary vectors of human malaria in sub-Saharan Africa. Many host genes have been shown to affect Plasmodium development in the mosquito, and so are expected to engage in an evolutionary arms race with the pathogen. However, there is little conclusive evidence that any of these mosquito genes evolve rapidly, or show other signatures of adaptive evolution. Methods Three serine protease inhibitors have previously been identified as candidate immune system genes mediating mosquito-Plasmodium interaction, and serine protease inhibitors have been identified as hot-spots of adaptive evolution in other taxa. Population-genetic tests for selection, including a recent multi-gene extension of the McDonald-Kreitman test, were applied to 16 serine protease inhibitors and 16 other genes sampled from the An. gambiae species complex in both East and West Africa. Results Serine protease inhibitors were found to show a marginally significant trend towards higher levels of amino acid diversity than other genes, and display extensive genetic structuring associated with the 2La chromosomal inversion. However, although serpins are candidate targets for strong parasite-mediated selection, no evidence was found for rapid adaptive evolution in these genes. Conclusion It is well known that phylogenetic and population history in the An. gambiae complex can present special problems for the application of standard population-genetic tests for selection, and this may explain the failure of this study to detect selection acting on serine protease inhibitors. The pitfalls of uncritically applying these tests in this species complex are highlighted, and the future prospects for detecting selection acting on the An. gambiae genome are discussed.

  14. Genetic and Morphological Analyses Demonstrate That Schizolecis guntheri (Siluriformes: Loricariidae) Is Likely to Be a Species Complex

    Science.gov (United States)

    Souza, Camila S.; Costa-Silva, Guilherme J.; Roxo, Fábio F.; Foresti, Fausto; Oliveira, Claudio

    2018-01-01

    Schizolecis is a monotypic genus of Siluriformes widely distributed throughout isolated coastal drainages of southeastern Brazil. Previous studies have shown that fish groups found in isolated river basins tend to differentiate over time in the absence of gene flow, resulting in allopatric speciation. In this study, we used partial sequences of the mitochondrial gene COI with the analysis of the General Mixed Yule Coalescent model (GMYC) and the Automatic Barcode Gap Discovery (ABGD) for single locus species delimitation, and a Principal Component Analysis (PCA) of external morphology to test the hypothesis that Schizolecis guntheri is a complex of species. We analyzed 94 samples of S. guntheri for GMYC and ABGD, and 82 samples for PCA from 22 coastal rivers draining to the Atlantic in southeastern Brazil from the Paraná State to the north of the Rio de Janeiro State. As a result, the GMYC model and the ABGD delimited five operational taxonomy units (OTUs – a nomenclature referred to in the present study of the possible new species delimited for the genetic analysis), a much higher number compared to the traditional alfa taxonomy that only recognizes S. guntheri across the isolated coastal rivers of Brazil. Furthermore, the PCA analysis suggests that S. guntheri is highly variable in aspects of external body proportions, including dorsal-fin spine length, pectoral-fin spine length, pelvic-fin spine length, lower caudal-fin spine length, caudal peduncle depth, anal width and mandibular ramus length. However, no exclusive character was found among the isolated populations that could be used to describe a new species of Schizolecis. Therefore, we can conclude, based on our results of PCA contrasting with the results of GMYC and ABGD, that S. guntheri represents a complex of species. PMID:29552028

  15. Genetic and Morphological Analyses Demonstrate That Schizolecis guntheri (Siluriformes: Loricariidae) Is Likely to Be a Species Complex.

    Science.gov (United States)

    Souza, Camila S; Costa-Silva, Guilherme J; Roxo, Fábio F; Foresti, Fausto; Oliveira, Claudio

    2018-01-01

    Schizolecis is a monotypic genus of Siluriformes widely distributed throughout isolated coastal drainages of southeastern Brazil. Previous studies have shown that fish groups found in isolated river basins tend to differentiate over time in the absence of gene flow, resulting in allopatric speciation. In this study, we used partial sequences of the mitochondrial gene COI with the analysis of the General Mixed Yule Coalescent model (GMYC) and the Automatic Barcode Gap Discovery (ABGD) for single locus species delimitation, and a Principal Component Analysis (PCA) of external morphology to test the hypothesis that Schizolecis guntheri is a complex of species. We analyzed 94 samples of S. guntheri for GMYC and ABGD, and 82 samples for PCA from 22 coastal rivers draining to the Atlantic in southeastern Brazil from the Paraná State to the north of the Rio de Janeiro State. As a result, the GMYC model and the ABGD delimited five operational taxonomy units (OTUs - a nomenclature referred to in the present study of the possible new species delimited for the genetic analysis), a much higher number compared to the traditional alfa taxonomy that only recognizes S. guntheri across the isolated coastal rivers of Brazil. Furthermore, the PCA analysis suggests that S. guntheri is highly variable in aspects of external body proportions, including dorsal-fin spine length, pectoral-fin spine length, pelvic-fin spine length, lower caudal-fin spine length, caudal peduncle depth, anal width and mandibular ramus length. However, no exclusive character was found among the isolated populations that could be used to describe a new species of Schizolecis . Therefore, we can conclude, based on our results of PCA contrasting with the results of GMYC and ABGD, that S. guntheri represents a complex of species.

  16. Genetic and Morphological Analyses Demonstrate That Schizolecis guntheri (Siluriformes: Loricariidae Is Likely to Be a Species Complex

    Directory of Open Access Journals (Sweden)

    Camila S. Souza

    2018-03-01

    Full Text Available Schizolecis is a monotypic genus of Siluriformes widely distributed throughout isolated coastal drainages of southeastern Brazil. Previous studies have shown that fish groups found in isolated river basins tend to differentiate over time in the absence of gene flow, resulting in allopatric speciation. In this study, we used partial sequences of the mitochondrial gene COI with the analysis of the General Mixed Yule Coalescent model (GMYC and the Automatic Barcode Gap Discovery (ABGD for single locus species delimitation, and a Principal Component Analysis (PCA of external morphology to test the hypothesis that Schizolecis guntheri is a complex of species. We analyzed 94 samples of S. guntheri for GMYC and ABGD, and 82 samples for PCA from 22 coastal rivers draining to the Atlantic in southeastern Brazil from the Paraná State to the north of the Rio de Janeiro State. As a result, the GMYC model and the ABGD delimited five operational taxonomy units (OTUs – a nomenclature referred to in the present study of the possible new species delimited for the genetic analysis, a much higher number compared to the traditional alfa taxonomy that only recognizes S. guntheri across the isolated coastal rivers of Brazil. Furthermore, the PCA analysis suggests that S. guntheri is highly variable in aspects of external body proportions, including dorsal-fin spine length, pectoral-fin spine length, pelvic-fin spine length, lower caudal-fin spine length, caudal peduncle depth, anal width and mandibular ramus length. However, no exclusive character was found among the isolated populations that could be used to describe a new species of Schizolecis. Therefore, we can conclude, based on our results of PCA contrasting with the results of GMYC and ABGD, that S. guntheri represents a complex of species.

  17. Four new bat species (Rhinolophus hildebrandtii complex reflect Plio-Pleistocene divergence of dwarfs and giants across an Afromontane archipelago.

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    Peter J Taylor

    Full Text Available Gigantism and dwarfism evolve in vertebrates restricted to islands. We describe four new species in the Rhinolophus hildebrandtii species-complex of horseshoe bats, whose evolution has entailed adaptive shifts in body size. We postulate that vicissitudes of palaeoenvironments resulted in gigantism and dwarfism in habitat islands fragmented across eastern and southern Africa. Mitochondrial and nuclear DNA sequences recovered two clades of R. hildebrandtii senso lato which are paraphyletic with respect to a third lineage (R. eloquens. Lineages differ by 7.7 to 9.0% in cytochrome b sequences. Clade 1 includes R. hildebrandtii sensu stricto from the east African highlands and three additional vicariants that speciated across an Afromontane archipelago through the Plio-Pleistocene, extending from the Kenyan Highlands through the Eastern Arc, northern Mozambique and the Zambezi Escarpment to the eastern Great Escarpment of South Africa. Clade 2 comprises one species confined to lowland savanna habitats (Mozambique and Zimbabwe. A third clade comprises R. eloquens from East Africa. Speciation within Clade 1 is associated with fixed differences in echolocation call frequency, and cranial shape and size in populations isolated since the late Pliocene (ca 3.74 Mya. Relative to the intermediate-sized savanna population (Clade 2, these island-populations within Clade 1 are characterised by either gigantism (South African eastern Great Escarpment and Mts Mabu and Inago in Mozambique or dwarfism (Lutope-Ngolangola Gorge, Zimbabwe and Soutpansberg Mountains, South Africa. Sympatry between divergent clades (Clade 1 and Clade 2 at Lutope-Ngolangola Gorge (NW Zimbabwe is attributed to recent range expansions. We propose an "Allometric Speciation Hypothesis", which attributes the evolution of this species complex of bats to divergence in constant frequency (CF sonar calls. The origin of species-specific peak frequencies (overall range = 32 to 46 kHz represents the

  18. Four new bat species (Rhinolophus hildebrandtii complex) reflect Plio-Pleistocene divergence of dwarfs and giants across an Afromontane archipelago.

    Science.gov (United States)

    Taylor, Peter J; Stoffberg, Samantha; Monadjem, Ara; Schoeman, Martinus Corrie; Bayliss, Julian; Cotterill, Fenton P D

    2012-01-01

    Gigantism and dwarfism evolve in vertebrates restricted to islands. We describe four new species in the Rhinolophus hildebrandtii species-complex of horseshoe bats, whose evolution has entailed adaptive shifts in body size. We postulate that vicissitudes of palaeoenvironments resulted in gigantism and dwarfism in habitat islands fragmented across eastern and southern Africa. Mitochondrial and nuclear DNA sequences recovered two clades of R. hildebrandtii senso lato which are paraphyletic with respect to a third lineage (R. eloquens). Lineages differ by 7.7 to 9.0% in cytochrome b sequences. Clade 1 includes R. hildebrandtii sensu stricto from the east African highlands and three additional vicariants that speciated across an Afromontane archipelago through the Plio-Pleistocene, extending from the Kenyan Highlands through the Eastern Arc, northern Mozambique and the Zambezi Escarpment to the eastern Great Escarpment of South Africa. Clade 2 comprises one species confined to lowland savanna habitats (Mozambique and Zimbabwe). A third clade comprises R. eloquens from East Africa. Speciation within Clade 1 is associated with fixed differences in echolocation call frequency, and cranial shape and size in populations isolated since the late Pliocene (ca 3.74 Mya). Relative to the intermediate-sized savanna population (Clade 2), these island-populations within Clade 1 are characterised by either gigantism (South African eastern Great Escarpment and Mts Mabu and Inago in Mozambique) or dwarfism (Lutope-Ngolangola Gorge, Zimbabwe and Soutpansberg Mountains, South Africa). Sympatry between divergent clades (Clade 1 and Clade 2) at Lutope-Ngolangola Gorge (NW Zimbabwe) is attributed to recent range expansions. We propose an "Allometric Speciation Hypothesis", which attributes the evolution of this species complex of bats to divergence in constant frequency (CF) sonar calls. The origin of species-specific peak frequencies (overall range = 32 to 46 kHz) represents the

  19. Alkaline cation complexing with calixarenes in electro-spray / mass spectrometry. Specificity for cesium, influence of solvation on ion species and radiolytic stability of the complexing media

    International Nuclear Information System (INIS)

    Allain, Francoise

    2000-01-01

    Radioactive waste management is a rather difficult issue. In order to reduce the volume of waste storage, particularly the Cs 135 (radioactive half-life 2.3 10 6 years), liquid-liquid extraction experiments have shown that crown calixarenes were able to selectively extract cesium cation in wastes. However, the stability under radiolysis of this type of macrocycle is unknown and is the theme of this thesis. Through the coupling of electro-spray and mass spectrometry, the selectivity of crown calixarenes for cesium has been confirmed. The necessity to optimize operating conditions during the utilization of this ionization mode was acknowledged for a correct interpretation of mass spectrum. The solvent nature, source temperature, applied voltage on the cone, gaseous phase stability and species ionization desorption rate are indeed parameters that should be taken into account. Experiments show that the solution species stability is inverse to the one in gaseous phase. In a solution, species stability is linked to the nature of the solvent (solvating power) whereas in gaseous phase, it is linked to the cationic affinity. In the current radiolysis conditions it has been demonstrated that calixarenes have a stable structure. Degradation products are very largely substitution products and do not hinder the caesium cation complexing. Concerning the quantitative aspect, an estimation was produced, however results are not satisfying: reference product synthesis is in fact necessary in order to establish calibration curves that will allow to precisely dose the various components derived from radiolysis [fr

  20. Effect of Acacia raddiana extracts on Fusarium oxysporum f. sp. albedinis, the causal agent of Bayoud

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    Noureddine BOULENOUAR

    2016-07-01

    Full Text Available In the present study, a medicinal plant from algerian Sahara (South-West of Algeria, Acacia raddiana has been used (leaves, bark to evaluate its extracts (reflux extraction with four solvents: methanol, ethyl acetate, dichloromethane, hexane on Fusarium oxysporum f. sp. albedinis (Foa. The Foa is the causal agent of the most dangerous disease of date palm (Phoenix dactylifera L.. The preliminary evaluation has been realized by agar diffusion technique and virulence test on potato tuber tissues. The extracts that present an inhibition or decrease the relative virulence (RV below 50% undergo phytochemical screening and direct bioautography. The bioautography has been used to localize the antifungal activity on the chromatogram and study the correlation with phytochemical screening data. Among eight extracts, five has been chosen for phytochemical screening and bioautography (2 leaves extracts and 3 bark extracts. Only six tests among 32 (22.58% present a detectable effect. The best effect is related to bark extract with ethyl acetate (inhibition diameter: 18mm, which is a moderate effect. Some extracts show an increase in RV. On the other hand, others decrease the RV. The best effect on RV is presented by hexanic extract of bark (RV=48%. The phytochemical screening highlighted the presence of flavonoids, tannins, coumarins and alkaloids in the studied plant. The direct bioautography has demonstrated no detectable effect. According to realized analyses, we can conclude that this species contains bioactive substances on Foa but need more precise analyses. The reason is simple, in addition to synergy principle in the crude extracts; the quantity of these metabolites is low compared to the detection level.

  1. Species of the Colletotrichum gloeosporioides complex associated with anthracnose diseases of Proteaceae

    NARCIS (Netherlands)

    Liu, F.; Damm, U.; Cai, L.; Crous, P.W.

    2013-01-01

    Anthracnose disease of Proteaceae has in the past chiefly been attributed to infections by C. acutatum, C. boninense and C. gloeosporioides. In the present study, a multi-locus phylogenetic analysis (ACT, CAL, CHS-1, GAPDH, GS, ITS, TUB2) revealed that strains of the C. gloeosporioides complex

  2. Analyses of volatiles produced by the African fruit fly species complex (Diptera, Tephritidae)

    Czech Academy of Sciences Publication Activity Database

    Břízová, Radka; Vaníčková, Lucie; Faťarová, M.; Ekesi, S.; Hoskovec, Michal; Kalinová, Blanka

    -, č. 540 (2015), s. 385-404 ISSN 1313-2989 Institutional support: RVO:61388963 Keywords : Ceratitis FAR complex * chemotaxonomy * male and female-borne volatiles * GCxGC-TOFMS * GC-EAD Subject RIV: EG - Zoology Impact factor: 0.938, year: 2015 http://zookeys.pensoft.net/articles.php?id=6223

  3. Hirudinella ventricosa (Pallas, 1774) Baird, 1853 represents a species complex based on ribosomal DNA.

    Science.gov (United States)

    Calhoun, Dana M; Curran, Stephen S; Pulis, Eric E; Provaznik, Jennifer M; Franks, James S

    2013-10-01

    Digeneans in the genus Hirudinella de Blainville, 1828 (Hirudinellidae) from three species of pelagic fishes, Acanthocybium solandri (Cuvier), Makaira nigricans Lacépède and Thunnus albacares (Bonnaterre), and one benthic fish, Mulloidichthys martinicus (Cuvier), from the Gulf of Mexico are investigated using comparison of ribosomal DNA. Four species are identified based on molecular differences: Hirudinella ventricosa (Pallas, 1774) Baird, 1853 from A. solandri, Hirudinella ahi Yamaguti, 1970 from T. albacares, and two unidentified but distinct species of Hirudinella, herein referred to as Hirudinella sp. A (from both M. nigricans and M. martinicus) and Hirudinella sp. B from M. nigricans. Additionally, H. ahi, based tentatively on morphological identification, is reported from Thunnus thynnus (Linnaeus). This represents the first record of a hirudinellid from M. martinicus and the first record of H. ahi from T. thynnus. A phylogeny of some Hemiurata Skrjabin & Guschanskaja, 1954 using partial fragments of the 28S rDNA sequences is consistent with earlier phylogenies and the position of the Hirudinellidae Dollfus, 1932 is well-supported as a derived group most closely related to the Syncoeliidae Looss, 1899.

  4. A review of the Paectes arcigera species complex (Guenée (Lepidoptera, Euteliidae

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    Michael Pogue

    2013-02-01

    Full Text Available Five new species of Paectes Hübner [1818] related to Paectes arcigera (Guenée (Puerto Rico, U.S. Virgin Islands, British Virgin Islands, Guadeloupe, Dominica, St. Lucia, Trinidad and P. longiformis Pogue (Brazil are described: P. asper sp. n. (Florida, Bahamas, Cuba, Cayman Islands, Jamaica, Haiti, Dominican Republic, Puerto Rico, British Virgin Islands, U.S. Virgin Islands, Dominica, Colombia, P. medialba sp. n. (Argentina, P. similis sp. n. (Brazil, P. sinuosa sp. n. (Argentina, Brazil, Paraguay, and P. tumida sp. n. (Colombia, Guyana, Suriname, French Guiana. Adults and genitalia are illustrated for all species. Taxonomic changes include the rev. stat. of P. nana (Walker (Florida, Greater Antilles, Mexico, Guatemala, Galapagos as a valid species and revised synonyms P. indefatigabilis Schaus and P. isabel Schaus as junior synonyms of P. nana instead of P. arcigera. New host records for P. sinuosa and P. nana reared on Brazilian peppertree (Schinus terebinthifolius Raddi, Anacardiaceae are presented. The holotype and female genitalia of P. obrotunda (Guenée are illustrated.

  5. A review of the Paectes arcigera species complex (Guenée) (Lepidoptera, Euteliidae)

    Science.gov (United States)

    Pogue, Michael G.

    2013-01-01

    Abstract Five new species of Paectes Hübner [1818] related to Paectes arcigera (Guenée) (Puerto Rico, U.S. Virgin Islands, British Virgin Islands, Guadeloupe, Dominica, St. Lucia, Trinidad) and Paectes longiformis Pogue (Brazil) are described: Paectes asper sp. n. (Florida, Bahamas, Cuba, Cayman Islands, Jamaica, Haiti, Dominican Republic, Puerto Rico, British Virgin Islands, U.S. Virgin Islands, Dominica, Colombia), Paectes medialba sp. n. (Argentina), Paectes similis sp. n. (Brazil), Paectes sinuosa sp. n. (Argentina, Brazil, Paraguay), and Paectes tumida sp. n. (Colombia, Guyana, Suriname, French Guiana). Adults and genitalia are illustrated for all species. Taxonomic changes include the rev. stat. of Paectes nana (Walker) (Florida, Greater Antilles, Mexico, Guatemala, Galapagos) as a valid species and revised synonyms Paectes indefatigabilis Schaus and Paectes isabel Schaus as junior synonyms of Paectes nana instead of Paectes arcigera. New host records for Paectes sinuosa and Paectes nana reared on Brazilian peppertree (Schinus terebinthifolius Raddi, Anacardiaceae) are presented. The holotype and female genitalia of Paectes obrotunda (Guenée) are illustrated. PMID:23730180

  6. The first European stand of Paramecium sonneborni (P. aurelia complex), a species known only from North America (Texas, USA).

    Science.gov (United States)

    Przyboś, Ewa; Tarcz, Sebastian; Rautian, Maria; Lebedeva, Natalia

    2014-06-01

    P. aurelia is currently defined as a complex of 15 sibling species including 14 species designated by Sonneborn (1975) and one, P. sonneborni, by Aufderheide et al. (1983). The latter was known from only one stand (Texas, USA). The main reason for the present study was a new stand of Paramecium in Cyprus, with strains recognized as P. sonneborni based on the results of strain crosses, cytological slides, and molecular analyses of three loci (ITS1-5.8S-ITS2-5'LSU rDNA, COI, CytB). The new stand of P. sonneborni in Europe shows that the species, previously considered endemic, may have a wider range. This demonstrates the impact of under-sampling on the knowledge of the biogeography of microbial eukaryotes. Phylogenetic trees based on all the studied fragments revealed that P. sonneborni forms a separate cluster that is closer to P. jenningsi and P. schewiakoffi than to the other members of the P. aurelia complex. Copyright © 2014 Elsevier GmbH. All rights reserved.

  7. Global species delimitation and phylogeography of the circumtropical ‘sexy shrimp’ Thor amboinensis reveals a cryptic species complex and secondary contact in the Indo-West Pacific

    KAUST Repository

    Titus, Benjamin M.

    2018-04-27

    Aim The “sexy shrimp” Thor amboinensis is currently considered a single circumtropical species. However, the tropical oceans are partitioned by hard and soft barriers to dispersal, providing ample opportunity for allopatric speciation. Herein, we test the null hypothesis that T. amboinensis is a single global species, reconstruct its global biogeographical history, and comment on population‐level patterns throughout the Tropical Western Atlantic. Location Coral reefs in all tropical oceans. Methods Specimens of Thor amboinensis were obtained through field collection and museum holdings. We used one mitochondrial (COI) and two nuclear (NaK, enolase) gene fragments for global species delimitation and phylogenetic analyses (n = 83 individuals, 30 sample localities), while phylogeographical reconstruction in the TWA was based on COI only (n = 303 individuals, 10 sample localities). Results We found evidence for at least five cryptic lineages (9%–22% COI pairwise sequence divergence): four in the Indo‐West Pacific and one in the Tropical Western Atlantic. Phylogenetic reconstruction revealed that endemic lineages from Japan and the South Central Pacific are more closely related to the Tropical Western Atlantic lineage than to a co‐occurring lineage that is widespread throughout the Indo‐West Pacific. Concatenated and species tree phylogenetic analyses differ in the placement of an endemic Red Sea lineage and suggest alternate dispersal pathways into the Atlantic. Phylogeographical reconstruction throughout the Tropical Western Atlantic reveals little genetic structure over more than 3,000 km. Main conclusions Thor amboinensis is a species complex that has undergone a series of allopatric speciation events and whose members are in secondary contact in the Indo‐West Pacific. Nuclear‐ and mitochondrial‐ gene phylogenies show evidence of introgression between lineages inferred to have been separated more than 20 Ma. Phylogenetic discordance between

  8. Insecticide susceptibility of Nezara viridula (Heteroptera: Pentatomidae) and three other stink bug species composing a soybean pest complex in Japan.

    Science.gov (United States)

    Takeuchi, Hiroaki; Endo, Nobuyuki

    2012-06-01

    The susceptibility of the stink bug species Nezara viridula (L.), Nezara antennata Scott, Piezodorus hybneri (Gmelin), and Riptortus pedestris (F.) to insecticides was tested, establishing their 50% lethal dose (LD50) values as baseline data. Third instars and adults of the four species were treated by topical application with seven insecticides: fenitrothion, fenthion, etofenprox, silafluofen, dinotefuran, clothianidin, and ethiprole. The weight of the stink bug and weight of the insecticide applied to each bug were used as explanatory variables in the probit regression analysis. The effect of the body weight on the dose-response relationship, the proportional model, was not uniform among the tested insecticide-stink bug combinations. However, the basic model fit all combinations and could estimate LD50 values successfully. Therefore, LD50 values at the medium (average) weight estimated by the basic model were selected to describe the susceptibility of the stink bugs. The LD50 value of silafluofen for N. viridula adults, and that of silafluofen and etofenprox for N. antennata adults, was at least 2,338 ng greater than the other species exposed to each insecticide. Almost all of the LD50 values for adults were over 10 times greater than those of the same species' nymphs treated with the same insecticide. Thus monitoring of occurring species and their developmental stages is important for controlling effectively the stink bug pest complex by insecticides, especially by silafluofen or etofenprox. The estimated LD50 values can be used as baseline data to compare the susceptibility of the species collected in another year or location.

  9. Nontuberculous mycobacterial species and Mycobacterium tuberculosis complex coinfection in patients with pulmonary tuberculosis in Dr. Soetomo Hospital, Surabaya, Indonesia

    Directory of Open Access Journals (Sweden)

    Ni Made Mertaniasih

    2017-01-01

    Full Text Available Objective/Background: The aim of this study was to analyze the detection of nontuberculous mycobacterial (NTM species derived from sputum specimens of pulmonary tuberculosis (TB suspects. Increasing prevalence and incidence of pulmonary infection by NTM species have widely been reported in several countries with geographical variation. Materials and Methods: Between January 2014 and September 2015, sputum specimens from chronic pulmonary TB suspect patients were analyzed. Laboratory examination of mycobacteria was conducted in the TB laboratory, Department of Clinical Microbiology, Dr. Soetomo Hospital, Surabaya. Detection and identification of mycobacteria were performed by the standard culture method using the BACTEC MGIT 960 system (BD and Lowenstein–Jensen medium. Identification of positive Mycobacterium tuberculosis complex (MTBC was based on positive acid-fast bacilli microscopic smear, positive niacin accumulation, and positive TB Ag MPT 64 test results (SD Bioline. If the growth of positive cultures and acid-fast bacilli microscopic smear was positive, but niacin accumulation and TB Ag MPT 64 (SD Bioline results were negative, then the isolates were categorized as NTM species. MTBC isolates were also tested for their sensitivity toward first-line anti-TB drugs, using isoniazid, rifampin, ethambutol, and streptomycin. Results: From 2440 sputum specimens of pulmonary TB suspect patients, 459 isolates (18.81% were detected as MTBC and 141 (5.78% as NTM species. Conclusion: From the analyzed sputum specimens, 18.81% were detected as MTBC and 5.78% as NTM species. Each pulmonary TB suspect patient needed clinical settings to suspect causative agents of MTBC and/or NTM species; clinicians have to understand the local epidemiological data for the evaluation of causes of lung infection to determine appropriate therapy.

  10. Compost and biochar alter mycorrhization, tomato root exudation and development of Fusarium oxysporum f. sp. lycopersici

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    Adnan eAkhter

    2015-07-01

    Full Text Available Soil amendments like compost and biochar are known to affect soil properties, plant growth as well as soil borne plant pathogens. Complex interactions based on microbial activity and abiotic characteristics are supposed to be responsible for suppressive properties of certain substrates, however, the specific mechanisms of action are still widely unknown. In the present study, the main focus was on the development of the soil borne pathogen, Fusarium oxysporum f.sp. lycopersici (Fol in tomato (Solanum lycopersicum L. and changes in root exudates of tomato plants grown in different soil substrate compositions, such as compost (Comp alone at application rate of 20 % (v/v, and in combination with wood biochar (WB; made from beech wood chips or green waste biochar (GWB, made from garden waste residues at application rate of 3 % (v/v, and/or with additional arbuscular mycorrhizal fungi (AMF. The association of GWB and AMF had a positive effect on tomato plants growth unlike to the plants grown in WB containing soil substrate. The AMF root colonization was not enhanced by the addition of WB or GWB in the soil substrate, though bio-protective effect of mycorrhization was evident in both biochar amended treatments against Fol. Compost and biochars altered root exudates differently, which is evident from variable response of in vitro growth and development of Fol. The microconidia germination was highest under in root exudates from plants grown in the soil containing compost and GWB, whereas root exudates of plants from substrate containing WB suppressed the mycelial growth and development of Fol. In conclusion, the plant growth response and disease suppression in biochar containing substrates with additional AMF was affected by the feedstock type. Moreover, application of compost and biochars in the soil influence the quality and composition of root exudates with respect to their effects on soil-dwelling fungi.

  11. An Evaluation Method for the Suppression of Pathogenic Fusarium oxysporum by Soil Microorganisms Using the Dilution Plate Technique.

    Science.gov (United States)

    Mitsuboshi, Masahiro; Kioka, Yuuzou; Noguchi, Katsunori; Asakawa, Susumu

    2016-09-29

    Soil-borne diseases caused by pathogenic microorganisms are one of the main factors responsible for the decline in crop yields in farmlands. Pathogenic Fusarium oxysporum causes serious damage to various crops, and, thus, a feasible diagnostic method for soil-borne diseases is required. We herein examined a simple method to evaluate the suppressiveness of soil microorganisms against a pathogen by co-cultivating indigenous soil microorganisms and a pathogenic fungus (F. oxysporum f. sp. spinaciae). We inoculated F. oxysporum onto the center of agar medium plates mixed with a dilution series of a suspension of organic fertilizers or soil. After an approximately one-week cultivation, the growth degree of F. oxysporum was estimated based on the size of the colonies that formed on the plates. The growth degree of F. oxysporum significantly differed among the organic fertilizers tested, indicating the usefulness of the method for evaluating suppressiveness by organic fertilizers. Differences in the growth degrees of F. oxysporum were associated with the incidence of disease in spinach on soil treated with organic fertilizers and inoculated with a pathogenic F. oxysporum strain. These results suggested that this method provides some useful information on the suppressiveness of organic fertilizers and soil against Fusarium wilt.

  12. Phylogenetic diversity of human pathogenic Fusarium and emergence of uncommon virulent species.

    Science.gov (United States)

    Salah, Husam; Al-Hatmi, Abdullah M S; Theelen, Bart; Abukamar, Mohammed; Hashim, Samar; van Diepeningen, Anne D; Lass-Florl, Cornelia; Boekhout, Teun; Almaslamani, Muna; Taj-Aldeen, Saad J

    2015-12-01

    Fusarium species cause a broad spectrum of infections. However, little is known about the etiological agents to the species level. We identified Fusarium species isolated from clinical specimens including those of high risk patients to better understand the species involved in the pathogenesis. A set of 44 Fusarium isolates were identified by two-locus sequence typing using partial sequences of the second largest subunit of RNA polymerase (RPB2) and translation elongation factor 1 alpha (TEF-1α). The identified species belonged to four species complexes (SC); the most common SC was Fusarium solani (FSSC) (75%), followed by Fusarium oxysporum (FOSC) (4.5%), Fusarium fujikuroi (FFSC) (13.6%), and Fusarium dimerum (FDSC) (6.8%). Sites of infections were nails (n = 19, 43.2%), skin (n = 7, 15.9%), cornea (n = 6, 13.6%), blood (n = 3, 9%), wound (n = 4, 6.8%), burn (n = 2, 4.5%), tissue (n = 2, 4.5%), and urine (n = 1, 2.27%). Fusarium acutatum was rare and seem restricted to the Middle East. Comorbidities associated with invasive infections were hematological malignancy and autoimmune disorders. Members of the FSSC predominantly caused cornea, nail and bloodstream infections. Less frequently encountered were the FOSC, FFSC and FDSC. More accurate molecular identification of Fusarium species is important to predict therapeutic outcome and the emergence of these species. Copyright © 2015 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  13. Nitrogen complex species and its chemical nature in TiO2 for visible-light sensitized photocatalysis

    International Nuclear Information System (INIS)

    Asahi, Ryoji; Morikawa, Takeshi

    2007-01-01

    A photocatalyst with high reactivity under visible-light has been desired to utilize solar irradiation or interior lighting efficiently. Nitrogen-doped TiO 2 revealed significant improvement in optical absorption and photocatalytic activity over TiO 2 under visible light. We have performed the first-principles calculations to study the detailed N complex species introduced in TiO 2 . The results include stable geometries, densities of states, formation energies, and core levels. The present systematic studies account for the long-term controversial issue on N-doped TiO 2 , in particular, regarding the detailed assignment of N 1s binding energies observed in the XPS measurement. The detailed analyses of the formation energies show that introducing the N species more in a controlled way via process conditions is crucial to achieve the optimized photocatalytic performance

  14. New molecular data shed light on the global phylogeny and species limits of the Rhipicephalus sanguineus complex.

    Science.gov (United States)

    Hekimoğlu, Olcay; Sağlam, İsmail K; Özer, Nurdan; Estrada-Peña, Agustin

    2016-07-01

    The Rhipicephalus sanguineus complex is a group of closely related tick species distributed all around the world. In this study, using mitochondrial 16S ribosomal DNA, new specimens of R sanguineus sensu lato from Turkey and Rhipicephalus camicasi from Kenya, were evaluated together with available sequences of this complex in GenBank. Our objectives were to delimit the complex, re-evaluate its global phylogeny and develop a reconstruction of its biogeographic history. Given Turkey's geographical location and its neighboring status within Africa, Asia and Europe, molecular information of R. sanguineus s.l. species from this region could have important implications both on a regional and global scale. Phylogenetic trees obtained with three methods (Bayesian, Maximum Likelihood and Maximum Parsimony) were highly similar and consensus trees gave the same branching patterns and similar node support values. A total of four different clades with up to 9 Operational Taxonomic Units formed strong monophyletic groups. Biogeographic reconstructions demonstrated the importance of populations in Middle East (Turkey) in the spread of the group from Europe to Africa and Asia. Data supported previous conclusions on the existence of two species of R. sanguineus s.l. in South America and the strong molecular similarity between R. camicasi and the so-called tropical lineage of R. sanguineus s.l. These results point to the need of a re-evaluation of most specimens designated as R. sanguineus s.l. in East Europe, Middle East, Africa and Asia after an adequate re-description of this taxon. Copyright © 2016 Elsevier GmbH. All rights reserved.

  15. Synergistic toxicity of Macondo crude oil and dispersant Corexit 9500A® to the Brachionus plicatilis species complex (Rotifera)

    International Nuclear Information System (INIS)

    Rico-Martínez, Roberto; Snell, Terry W.; Shearer, Tonya L.

    2013-01-01

    Using the marine rotifer Brachionus plicatilis acute toxicity tests, we estimated the toxicity of Corexit 9500A ® , propylene glycol, and Macondo oil. Ratios of 1:10, 1:50 and 1:130 for Corexit 9500A ® :Macondo oil mixture represent: maximum exposure concentrations, recommended ratios for deploying Corexit (1:10–1:50), 1:130 the actual dispersant:oil ratio used in the Deep Water Horizon spill. Corexit 9500A ® and oil are similar in their toxicity. However, when Corexit 9500A ® and oil are mixed, toxicity to B. manjavacas increases up to 52-fold. Extrapolating these results to the oil released by the Macondo well, suggests underestimation of increased toxicity from Corexit application. We found small differences in sensitivity among species of the B. plicatilis species complex, likely reflecting phylogenetic similarity. Just 2.6% of the water-accommodated fraction of oil inhibited rotifer cyst hatching by 50%, an ecologically significant result because rotifer cyst in sediments are critical resources for the recolonization of populations each Spring. - Highlights: ► We determined LC50's of Corexit 9500A ® , propylene glycol, and oil to B. plicatilis. ► Corexit 9500A ® and oil are equivalent in toxicity. ► When Corexit 9500A ® and oil are mixed, toxicity increases 52-fold to B. plicatilis. ► Results suggest underestimation of increased toxicity due to Corexit application. ► Sensitivity differences are small among species of the B. plicatilis species complex. - Using Brachionus plicatilis acute toxicity tests we estimated Corexit 9500A ® and oil toxicity. When these compounds are mixed a 52-fold increase in toxicity was observed.

  16. Protein expression parallels thermal tolerance and ecologic changes in the diversification of a diving beetle species complex.

    Science.gov (United States)

    Hidalgo-Galiana, A; Monge, M; Biron, D G; Canals, F; Ribera, I; Cieslak, A

    2016-01-01

    Physiological changes associated with evolutionary and ecological processes such as diversification, range expansion or speciation are still incompletely understood, especially for non-model species. Here we study differences in protein expression in response to temperature in a western Mediterranean diving beetle species complex, using two-dimensional differential gel electrophoresis with one Moroccan and one Iberian population each of Agabus ramblae and Agabus brunneus. We identified proteins with significant expression differences after thermal treatments comparing them with a reference EST library generated from one of the species of the complex (A. ramblae). The colonisation during the Middle Pleistocene of the Iberian peninsula by A. ramblae, where maximum temperatures and seasonality are lower than in the ancestral north African range, was associated with changes in the response to 27 °C in proteins related to energy metabolism. The subsequent speciation of A. brunneus from within populations of Iberian A. ramblae was associated with changes in the expression of several stress-related proteins (mostly chaperons) when exposed to 4 °C. These changes are in agreement with the known tolerance to lower temperatures of A. brunneus, which occupies a larger geographical area with a wider range of climatic conditions. In both cases, protein expression changes paralleled the evolution of thermal tolerance and the climatic conditions experienced by the species. However, although the colonisation of the Iberian peninsula did not result in morphological change, the speciation process of A. brunneus within Iberia involved genetic isolation and substantial differences in male genitalia and body size and shape.

  17. Peptaibol, secondary-metabolite, and hydrophobin pattern of commercial biocontrol agents formulated with species of the Trichoderma harzianum complex.

    Science.gov (United States)

    Degenkolb, Thomas; Fog Nielsen, Kristian; Dieckmann, Ralf; Branco-Rocha, Fabiano; Chaverri, Priscila; Samuels, Gary J; Thrane, Ulf; von Döhren, Hans; Vilcinskas, Andreas; Brückner, Hans

    2015-04-01

    The production of bioactive polypeptides (peptaibiotics) in vivo is a sophisticated adaptation strategy of both mycoparasitic and saprotrophic Trichoderma species for colonizing and defending their natural habitats. This feature is of major practical importance, as the detection of peptaibiotics in plant-protective Trichoderma species, which are successfully used against economically relevant bacterial and fungal plant pathogens, certainly contributes to a better understanding of these complex antagonistic interactions. We analyzed five commercial biocontrol agents (BCAs), namely Canna(®) , Trichosan(®) , Vitalin(®) , Promot(®) WP, and TrichoMax(®) , formulated with recently described species of the Trichoderma harzianum complex, viz. T. afroharzianum, T. simmonsii, and T. guizhouense. By using the well-established, HPLC/MS-based peptaibiomics approach, it could unequivocally be demonstrated that all of these formulations contained new and recurrent peptaibols, i.e., peptaibiotics carrying an acetylated N-terminus, the C-terminus of which is reduced to a 1,2-amino alcohol. Their chain lengths, including the amino alcohol, were 11, 14, and 18 residues, respectively. Peptaibols were also to be the dominating secondary metabolites in plate cultures of the four strains obtained from four of the Trichoderma- based BCAs, contributing 95% of the UHPLC-UV/VIS peak areas and 99% of the total ion count MS peak area from solid media. Furthermore, species-specific hydrophobins, as well as non-peptaibiotic secondary metabolites, were detected, the latter being known for their antifungal, siderophore, or plant-growth-promoting activities. Notably, none of the isolates produced low-molecular weight mycotoxins. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  18. Interspecific introgression and changes in population structure in a flatfish species complex after the Prestige accident

    International Nuclear Information System (INIS)

    Crego-Prieto, V.; Danancher, D.; Campo, D.; Perez, J.; Garcia-Vazquez, E.; Roca, A.

    2013-01-01

    Highlights: • Impact of Prestige oil spill was studied on two sympatric megrim fish populations. • Samples before and nine years after the accident were genetically analyzed. • A large proportion of post-F1 interspecific hybrids was found in the polluted area. • Both species’ population structure was altered by introgression of foreign alleles. • The spillage likely promoted a hybrid zone for Lepidorhombus in the areas affected. -- Abstract: Oil spills cause aggressive impacts on marine ecosystems affecting immense areas and the species inhabiting them. If wastes are not cleaned up properly, the remnants may affect local populations for a long time. This work focuses on the long-term impacts of the Prestige spillage that occurred off Galician coast (Spain) in November 2002. Model species were two sympatric flatfish, the megrims Lepidorhombus whiffiagonis and Lepidorhombus boscii. Samples obtained before and nine years after the Prestige accident from affected and unaffected areas were genotyped for six hypervariable nuclear markers and for the mitochondrial D-loop sequence. The results revealed a high proportion of post-F1 interspecific hybrids in the area affected, and also increased intraspecific population differentiation likely due to such localized introgression of foreign genes. These changes suggest the appearance of a hybrid zone following the accident and emphasize the need of paying special attention to potential evolutionary impacts of oil spills

  19. Burkholderia humptydooensis sp. nov., a New Species Related to Burkholderia thailandensis and the Fifth Member of the Burkholderia pseudomallei Complex.

    Science.gov (United States)

    Tuanyok, Apichai; Mayo, Mark; Scholz, Holger; Hall, Carina M; Allender, Christopher J; Kaestli, Mirjam; Ginther, Jennifer; Spring-Pearson, Senanu; Bollig, Molly C; Stone, Joshua K; Settles, Erik W; Busch, Joseph D; Sidak-Loftis, Lindsay; Sahl, Jason W; Thomas, Astrid; Kreutzer, Lisa; Georgi, Enrico; Gee, Jay E; Bowen, Richard A; Ladner, Jason T; Lovett, Sean; Koroleva, Galina; Palacios, Gustavo; Wagner, David M; Currie, Bart J; Keim, Paul

    2017-03-01

    During routine screening for Burkholderia pseudomallei from water wells in northern Australia in areas where it is endemic, Gram-negative bacteria (strains MSMB43 T , MSMB121, and MSMB122) with a similar morphology and biochemical pattern to B. pseudomallei and B. thailandensis were coisolated with B. pseudomallei on Ashdown's selective agar. To determine the exact taxonomic position of these strains and to distinguish them from B. pseudomallei and B. thailandensis , they were subjected to a series of phenotypic and molecular analyses. Biochemical and fatty acid methyl ester analysis was unable to distinguish B. humptydooensis sp. nov. from closely related species. With matrix-assisted laser desorption ionization-time of flight analysis, all isolates grouped together in a cluster separate from other Burkholderia spp. 16S rRNA and recA sequence analyses demonstrated phylogenetic placement for B. humptydooensis sp. nov. in a novel clade within the B. pseudomallei group. Multilocus sequence typing (MLST) analysis of the three isolates in comparison with MLST data from 3,340 B. pseudomallei strains and related taxa revealed a new sequence type (ST318). Genome-to-genome distance calculations and the average nucleotide identity of all isolates to both B. thailandensis and B. pseudomallei , based on whole-genome sequences, also confirmed B. humptydooensis sp. nov. as a novel Burkholderia species within the B. pseudomallei complex. Molecular analyses clearly demonstrated that strains MSMB43 T , MSMB121, and MSMB122 belong to a novel Burkholderia species for which the name Burkholderia humptydooensis sp. nov. is proposed, with the type strain MSMB43 T (American Type Culture Collection BAA-2767; Belgian Co-ordinated Collections of Microorganisms LMG 29471; DDBJ accession numbers CP013380 to CP013382). IMPORTANCE Burkholderia pseudomallei is a soil-dwelling bacterium and the causative agent of melioidosis. The genus Burkholderia consists of a diverse group of species, with

  20. Proteomics of Fusarium oxysporum race 1 and race 4 reveals enzymes involved in carbohydrate metabolism and ion transport that might play important roles in banana Fusarium wilt.

    Science.gov (United States)

    Sun, Yong; Yi, Xiaoping; Peng, Ming; Zeng, Huicai; Wang, Dan; Li, Bo; Tong, Zheng; Chang, Lili; Jin, Xiang; Wang, Xuchu

    2014-01-01

    Banana Fusarium wilt is a soil-spread fungal disease caused by Fusarium oxysporum. In China, the main virulence fungi in banana are F. oxysporum race 1 (F1, weak virulence) and race 4 (F4, strong virulence). To date, no proteomic analyses have compared the two races, but the difference in virulence between F1 and F4 might result from their differentially expressed proteins. Here we report the first comparative proteomics of F1 and F4 cultured under various conditions, and finally identify 99 protein species, which represent 59 unique proteins. These proteins are mainly involved in carbohydrate metabolism, post-translational modification, energy production, and inorganic ion transport. Bioinformatics analysis indicated that among the 46 proteins identified from F4 were several enzymes that might be important for virulence. Reverse transcription PCR analysis of the genes for 15 of the 56 proteins revealed that their transcriptional patterns were similar to their protein expression patterns. Taken together, these data suggest that proteins involved in carbohydrate metabolism and ion transport may be important in the pathogenesis of banana Fusarium wilt. Some enzymes such as catalase-peroxidase, galactosidase and chitinase might contribute to the strong virulence of F4. Overexpression or knockout of the genes for the F4-specific proteins will help us to further understand the molecular mechanism of Fusarium-induced banana wilt.

  1. NADPH oxidase complex-derived reactive oxygen species, the actin cytoskeleton, and rho GTPases in cell migration

    DEFF Research Database (Denmark)

    Stanley, Alanna; Thompson, Kerry; Hynes, Ailish

    2014-01-01

    Abstract Significance: Rho GTPases are historically known to be central regulators of actin cytoskeleton reorganization. This affects many processes including cell migration. In addition, members of the Rac subfamily are known to be involved in reactive oxygen species (ROS) production through...... mediating cytoskeletal reorganization. Critical Issues: The role of the actin cytoskeleton in providing a scaffold for components of the Nox complex needs to be examined in the light of these new advances. During cell migration, Rho GTPases, ROS, and cytoskeletal organization appear to function as a complex...... compartments. This in conjunction with the analysis of tissues lacking specific Rho GTPases, and Nox components will facilitate a detailed examination of the interactions of these structures with the actin cytoskeleton. In combination with the analysis of ROS production, including its subcellular location...

  2. Description, microhabitat selection and infection patterns of sealworm larvae (Pseudoterranova decipiens species complex, nematoda: ascaridoidea) in fishes from Patagonia, Argentina

    Science.gov (United States)

    2013-01-01

    Background Third-stage larvae of the Pseudoterranova decipiens species complex (also known as sealworms) have been reported in at least 40 marine fish species belonging to 21 families and 10 orders along the South American coast. Sealworms are a cause for concern because they can infect humans who consume raw or undercooked fish. However, despite their economic and zoonotic importance, morphological and molecular characterization of species of Pseudoterranova in South America is still scarce. Methods A total of 542 individual fish from 20 species from the Patagonian coast of Argentina were examined for sealworms. The body cavity, the muscles, internal organs, and the mesenteries were examined to detect nematodes. Sealworm larvae were removed from their capsules and fixed in 70% ethanol. For molecular identification, partial fragments of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) were amplified for 10 isolates from 4 fish species. Morphological and morphometric data of sealworms were also obtained. Results A total of 635 larvae were collected from 12 fish species. The most infected fish was Prionotus nudigula, followed by Percophis brasiliensis, Acanthistius patachonicus, Paralichthys isosceles, and Pseudopercis semifasciata. Sequences obtained for the cox1 of sealworms from A. patachonicus, P. isosceles, P. brasiliensis and P. nudigula formed a reciprocally monophyletic lineage with published sequences of adult specimens of Pseudoterranova cattani from the South American sea lion Otaria flavescens, and distinct from the remaining 5 species of Pseudoterranova. A morphological description, including drawings and scanning electron microscopy photomicrographs of these larvae is provided. Sealworms collected from Argentinean fishes did not differ in their diagnostic traits from the previously described larvae of P. cattani. However a discriminant analysis suggests that specimens from P. nudigula were significantly larger than those from other fishes

  3. Description, microhabitat selection and infection patterns of sealworm larvae (Pseudoterranova decipiens species complex, nematoda: ascaridoidea) in fishes from Patagonia, Argentina.

    Science.gov (United States)

    Hernández-Orts, Jesús S; Aznar, Francisco J; Blasco-Costa, Isabel; García, Néstor A; Víllora-Montero, María; Crespo, Enrique A; Raga, Juan A; Montero, Francisco E

    2013-08-29

    Third-stage larvae of the Pseudoterranova decipiens species complex (also known as sealworms) have been reported in at least 40 marine fish species belonging to 21 families and 10 orders along the South American coast. Sealworms are a cause for concern because they can infect humans who consume raw or undercooked fish. However, despite their economic and zoonotic importance, morphological and molecular characterization of species of Pseudoterranova in South America is still scarce. A total of 542 individual fish from 20 species from the Patagonian coast of Argentina were examined for sealworms. The body cavity, the muscles, internal organs, and the mesenteries were examined to detect nematodes. Sealworm larvae were removed from their capsules and fixed in 70% ethanol. For molecular identification, partial fragments of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) were amplified for 10 isolates from 4 fish species. Morphological and morphometric data of sealworms were also obtained. A total of 635 larvae were collected from 12 fish species. The most infected fish was Prionotus nudigula, followed by Percophis brasiliensis, Acanthistius patachonicus, Paralichthys isosceles, and Pseudopercis semifasciata. Sequences obtained for the cox1 of sealworms from A. patachonicus, P. isosceles, P. brasiliensis and P. nudigula formed a reciprocally monophyletic lineage with published sequences of adult specimens of Pseudoterranova cattani from the South American sea lion Otaria flavescens, and distinct from the remaining 5 species of Pseudoterranova. A morphological description, including drawings and scanning electron microscopy photomicrographs of these larvae is provided. Sealworms collected from Argentinean fishes did not differ in their diagnostic traits from the previously described larvae of P. cattani. However a discriminant analysis suggests that specimens from P. nudigula were significantly larger than those from other fishes. Most of the sealworms were

  4. Chemical communication between the endophytic fungus Paraconiothyrium variabile and the phytopathogen Fusarium oxysporum.

    Directory of Open Access Journals (Sweden)

    Audrey Combès

    Full Text Available Paraconiothyrium variabile, one of the specific endophytic fungi isolated from the host plant Cephalotaxus harringtonia, possesses the faculty to inhibit the growth of common phytopathogens, thus suggesting a role in its host protection. A strong antagonism between the endophyte P. variabile and Fusarium oxysporum was observed and studied using optic and electronic microscopies. A disorganization of the mycelium of F. oxysporum was thus noticed. Interestingly, the biological effect of the main secondary metabolites isolated from P. variabile against F. oxysporum did not account for this strong antagonism. However, a metabolomic approach of pure fungal strains and confrontation zones using the data analysis tool XCMS were analyzed and pointed out a competition-induced metabolite production by the endophyte in the presence of the phytopathogen. Subsequent MS/MS fragmentations permitted to identify one of the induced metabolites as 13-oxo-9,11-octadecadienoic acid and highlighted a negative modulation of the biosynthesis of beauvericin, one of the most potent mycotoxin of F. oxysporum, during the competition with the endophyte.

  5. Genetic transformation of Fusarium oxysporum f.sp. gladioli with Agrobacterium to study pathogenesis in Gladiolus

    Science.gov (United States)

    Fusarium rot caused by Fusarium oxysporum f.sp. gladioli (Fog) is one of the most serious diseases of Gladiolus, both in the field and in stored bulbs. In order to study the pathogenesis of this fungus, we have transformed Fog with Agrobacterium tumefaciens binary vectors containing the hygromycin B...

  6. Comparison of Fusarium oxysporum fsp lycopersici races 1, 2 and 3 ...

    African Journals Online (AJOL)

    Dr J. T. Ekanem

    Sequence analysis of genomic fragments from the intergenic spacer region from three isolates of. Fusarium oxysporum fsp lycoperisci and fsp radicis lycopersici was carried out using the big dye terminator sequencing procedure. Two conditions of the DNA templates were also evaluated for their influence on the outcome of ...

  7. NADPH-dependent D-aldose reductases and xylose fermentation in Fusarium oxysporum

    DEFF Research Database (Denmark)

    Panagiotou, Gianni; Christakopoulos, P.

    2004-01-01

    Two aldose (xylose) reductases (ARI and ARII) from Fusarium oxysporum were purified and characterized. The native ARI was a monomer with M-r 41000, pI 5.2 and showed a 52-fold preference for NADPH over NADH, while ARII was homodimeric with a subunit of M-r 37000, pI 3.6 and a 60-fold preference...

  8. Molecular markers for improving control of soil-borne pathogen Fusarium oxysporum in sugar beet

    Science.gov (United States)

    Fusarium oxysporum f. sp. betae (FOB) is an important pathogen of sugar beet worldwide causing leaf yellowing and vascular discoloration. The use of tolerant varieties is one of the most effective methods for managing this disease. In this study, a large germplasm collection,comprised of 29 sugar be...

  9. Penapisan Cendawan Antagonis Indigenos Rizosfer Jahe dan Uji Daya Hambatnya terhadap Fusarium oxysporum f. sp. zingiberi

    Directory of Open Access Journals (Sweden)

    Nurbailis Nurbailis

    2015-02-01

    Full Text Available Ginger rot disease caused by Fusarium oxysporum f. sp. zingiberi is difficult to control because the pathogen is soil borne and is able to form clamidospore as resting structure. The aim of this study was to obtain indigenous antagonistic fungi from ginger rhizosphere which is potential for suppressing the growth of F. oxysporum f. sp. zingiberi. Fungi isolated from ginger rhizosphere were subjected for antagonism assay using dual culture method. Fungi isolates showed capability to inhibit F. oxysporum f. sp. zingiberii were then identified based on morphology characters. Eleven isolates were successfully isolated, but only 9 isolates showed the potentials of suppressing the growth of F. oxysporum f. sp.  zingiberi. All 9 isolates i.e. AB4, GC1, BB1, AB1, AB2, K12, GC3, K11 and GC2 had antibiosis activity, and 3 isolates among them i.e. AB2, BB1 and K11 showed competition mechanism. Based on morphology characters the isolates were identified as Penicillium spp. (4 isolates, Trichoderma spp. (3 isolates, and Aspergillus spp. (2 isolates.

  10. Response of AtNPR1-expressing cotton plants to Fusarium oxysporum f. sp. vasinfectum isolates

    Science.gov (United States)

    In our earlier investigation, we had demonstrated that transgenic cotton plants expressing AtNPR1 showed significant tolerance to Fusarium oxysporum f. sp. vasinfectum, isolate 11 (Fov11) and several other pathogens. The current study was designed to further characterize the nature of the protectio...

  11. Detection and control of Fusarium oxysporum and Cylindrocarpon destructans in forest nursery soils

    Science.gov (United States)

    Catherine Crosby; Lynne Carpenter-Boggs; Stewart Higgins; Nabil Khadduri

    2010-01-01

    Fusarium oxysporum and Cylindrocarpon destructans cause root disease that leads to significant crop losses in forest nurseries when not treated. Treatment currently relies on methyl bromide fumigation to eradicate soil pathogens. New environmental protection laws, however, are phasing out methyl bromide. Alternative chemical treatments are being tested, as well as...

  12. Evaluation of methods to detect the cotton pathogen Fusarium oxysporum f. sp. vasinfectum race 4

    Science.gov (United States)

    Fusarium wilt caused by Fusarium oxysporum f. sp. vasinfectum (Fov) is an important disease of cotton. Fov race 4, identified in the San Joaquin Valley of California, has caused serious losses and is a potential threat to US cotton production. Tests have been developed to rapidly identify race 4 i...

  13. Genetic diversity, virulence, and Meloidogyne incognita interactions of Fusarium oxysporum isolates causing cotton wilt in Georgia

    Science.gov (United States)

    Locally severe outbreaks of Fusarium wilt of cotton (Gossypium spp.) in South Georgia raised concerns about the genotypes of the causal pathogen, Fusarium oxysporum f. sp. vasinfectum. Vegetative complementation tests and DNA sequence analysis were used to determine genetic diversity among 492 F. ox...

  14. Comparison of virulence between vascular competent and incompetent Fusarium oxysporum f. sp. vasinfectum pathotypes

    Science.gov (United States)

    The Australian biotype and California race 4 isolates of Fusarium oxysporum f. sp. Vasinfectum (Fov) are pathologically distinct from the Fov U.S. race 1 isolates in that they do not cause disease when stem-puncture inoculated while race 1 isolates do. When root-dip inoculation method was used, bot...

  15. Root rot symptoms in sugar beet lines caused by Fusarium oxysporum f. sp. betae

    Science.gov (United States)

    The soil-borne fungus Fusarium oxysporum may cause both Fusarium yellows and Fusarium root rot diseases with severe yield losses in cultivated sugar beet worldwide. These two diseases cause similar foliar symptoms but different root response and have been proposed to be due to two distinct F. oxyspo...

  16. The Concept of Ecthyma Gangrenosum Illustrated by a Fusarium oxysporum Infection in an Immunocompetent Individual.

    Science.gov (United States)

    Jiang, Yanping; Al-Hatmi, Abdullah M S; Xiang, Yining; Cao, Yu; van den Ende, Albert H G Gerrits; Curfs-Breuker, Ilse; Meis, Jacques F; Lu, Hongguang; de Hoog, G Sybren

    2016-10-01

    Ecthyma gangrenosum (EG) involves necrotic cutaneous lesions caused by bacteria, mainly Pseudomonas aeruginosa, and is usually seen in immunocompromised patients with septicemia. However, clinically similar infections have been published with fungi as etiologic agents. We present a case of an EG-like lesion due to Fusarium oxysporum confirmed by clinical diagnosis, culture and molecular identification and discuss the definition of EG.

  17. Engineering of the redox imbalance of Fusarium oxysporum enables anaerobic growth on xylose

    DEFF Research Database (Denmark)

    Panagiotou, Gianni; Christakopoulos, Paul; Grotkjær, Thomas

    2006-01-01

    Dissimilatory nitrate reduction metabolism, of the natural xylose-fermenting fungus Fusarium oxysporum, was used as a strategy to achieve anaerobic growth and ethanol production from xylose. Beneficial alterations of the redox fluxes and thereby of the xylose metabolism were obtained by taking ad...

  18. A DNA-Based Procedure for In Planta Detection of Fusarium oxysporum f. sp. phaseoli.

    Science.gov (United States)

    Alves-Santos, Fernando M; Ramos, Brisa; García-Sánchez, M Asunción; Eslava, Arturo P; Díaz-Mínguez, José María

    2002-03-01

    ABSTRACT We have characterized strains of Fusarium oxysporum from common bean fields in Spain that were nonpathogenic on common bean, as well as F. oxysporum strains (F. oxysporum f. sp. phaseoli) pathogenic to common bean by random amplified polymorphic DNA (RAPD) analysis. We identified a RAPD marker (RAPD 4.12) specific for the highly virulent pathogenic strains of the seven races of F. oxysporum f. sp. phaseoli. Sequence analysis of RAPD 4.12 allowed the design of oligonucleotides that amplify a 609-bp sequence characterized amplified region (SCAR) marker (SCAR-B310A280). Under controlled environmental and greenhouse conditions, detection of the pathogen by polymerase chain reaction was 100% successful in root samples of infected but still symptomless plants and in stem samples of plants with disease severity of >/=4 in the Centro Internacional de Agricultura Tropical (CIAT; Cali, Colombia) scale. The diagnostic procedure can be completed in 5 h and allows the detection of all known races of the pathogen in plant samples at early stages of the disease with no visible symptoms.

  19. First report of Fusarium wilt of alfalfa caused by Fusarium oxysporum f. sp. medicaginis in Wisconsin

    Science.gov (United States)

    Fusarium wilt, caused by Fusarium oxysporum f. sp. medicaginis, is an economically important vascular disease of alfalfa (Medicago sativa) throughout the world. Alfalfa plants with foliar wilt symptoms and reddish-brown arcs in roots consistent with Fusarium wilt were observed in disease assessment ...

  20. The effector repertoire of Fusarium oxysporum determines the tomato xylem proteome composition following infection

    NARCIS (Netherlands)

    Gawehns, Fleur; Ma, Lisong; Bruning, Oskar; Houterman, Petra M.; Boeren, Sjef; Cornelissen, B.J.C.; Rep, Martijn; Takken, Frank L.W.

    2015-01-01

    Plant pathogens secrete small proteins, of which some are effectors that promote infection. During colonization of the tomato xylem vessels the fungus Fusarium oxysporum f.sp. lycopersici (Fol) secretes small proteins that are referred to as SIX (Secreted In Xylem) proteins. Of these, Six1

  1. MITEs in the promoters of effector genes allow prediction of novel virulence genes in Fusarium oxysporum

    NARCIS (Netherlands)

    Schmidt, S.M.; Houterman, P.M.; Schreiver, I.; Ma, L.; Amyotte, S.; Chellappan, B.; Boeren, S.; Takken, F.L.W.; Rep, M.

    2013-01-01

    Background The plant-pathogenic fungus Fusarium oxysporum f.sp.lycopersici (Fol) has accessory, lineage-specific (LS) chromosomes that can be transferred horizontally between strains. A single LS chromosome in the Fol4287 reference strain harbors all known Fol effector genes. Transfer of this

  2. Pathogenicity and genetic diversity of Fusarium oxysporum causing soybean root rot in northeast China

    Science.gov (United States)

    Soybean is an important edible legume cultivated around the world. However, soybean production is seriously impacted by the widespread occurrence of root rot disease. In this study, genetic diversity and pathogenicity of Fusarium oxysporum associated with root rot of soybean in Heilongjiang province...

  3. Engineering of the redox imbalance of Fusarium oxysporum enables anaerobic growth on xylose.

    Science.gov (United States)

    Panagiotou, Gianni; Christakopoulos, Paul; Grotkjaer, Thomas; Olsson, Lisbeth

    2006-09-01

    Dissimilatory nitrate reduction metabolism, of the natural xylose-fermenting fungus Fusarium oxysporum, was used as a strategy to achieve anaerobic growth and ethanol production from xylose. Beneficial alterations of the redox fluxes and thereby of the xylose metabolism were obtained by taking advantage of the regeneration of the cofactor NAD(+) during the denitrification process. In batch cultivations, nitrate sustained growth under anaerobic conditions (1.21 g L(-1) biomass) and simultaneously a maximum yield of 0.55 moles of ethanol per mole of xylose was achieved, whereas substitution of nitrate with ammonium limited the growth significantly (0.15 g L(-1) biomass). Using nitrate, the maximum acetate yield was 0.21 moles per mole of xylose and no xylitol excretion was observed. Furthermore, the network structure in the central carbon metabolism of F. oxysporum was characterized in steady state. F. oxysporum grew anaerobically on [1-(13)C] labelled glucose and unlabelled xylose in chemostat cultivation with nitrate as nitrogen source. The use of labelled substrate allowed the precise determination of the glucose and xylose contribution to the carbon fluxes in the central metabolism of this poorly described microorganism. It was demonstrated that dissimilatory nitrate reduction allows F. oxysporum to exhibit typical respiratory metabolic behaviour with a highly active TCA cycle and a large demand for NADPH.

  4. Effect of synthetic and natural media on lipid production from Fusarium oxysporum

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    Leonidas Matsakas

    2017-11-01

    Conclusions: It was demonstrated that F. oxysporum can be used as an efficient oleaginous microorganism, with sweet sorghum serving as an excellent raw material for the cultivation of the fungus. The lipids obtained during this work were also found to have a fatty acid profile with good potentials to be used for biodiesel production.

  5. Influence of Bacillus polymyxa on the growth and development of Fusarium oxysporum f. sp. tulipae

    Directory of Open Access Journals (Sweden)

    Alicja Saniewska

    2013-12-01

    Full Text Available Antagonistic effect of Bacillus polymyxa, strain S13, toward Fusarium oxysporum f. sp. tulipae was evaluated iii vitro and in vivo. The growth of the pathogen was greatly inhibited in dual cultures with Bacillus polymyxa on potato dextrose agar. Suspension of B. polymyxa and its filtrate substantially inhibited spore germination and development of Fusarium oxysporuum f. sp. tulipae on tulip bulbs.

  6. Selection of antagonistic bacteria isolated from the Physalis peruviana rhizosphere against Fusarium oxysporum.

    Science.gov (United States)

    Urrea, R; Cabezas, L; Sierra, R; Cárdenas, M; Restrepo, S; Jiménez, P

    2011-09-01

    Cape gooseberries (Physalis peruviana) have become increasingly important in Colombia for both domestic consumption and the international export market. Vascular wilting caused by Fusarium oxysporum is the most damaging disease to P. peruviana crops in Colombia. The control of this pathogen is mainly carried out by chemical and cultural practices, increasing production costs and generating resistance. Therefore, the objectives of this study were to test rhizobacteria isolates from P. peruviana rhizosphere against F. oxysporum under in vitro and in vivo conditions. Over 120 strains were isolated, and five were selected for their high inhibition of F. oxysporum growth and conidia production under in vitro conditions. These strains inhibited growth by 41-58% and reduced three- to fivefold conidia production. In the in vivo assays, all the tested isolates significantly reduced fungal pathogenicity in terms of virulence. Isolate B-3.4 was the most efficient in delaying the onset of the first symptoms. All isolates were identified as belonging to the genus Pseudomonas except for A-19 (Bacillus sp.). Our results confirmed that there are prospective rhizobacteria strains that can be used as biological control agents; some of them being able to inhibit in vitro F. oxysporum growth and sporulation. Incorporating these bacteria into biological control strategies for the disease that causes high economical losses in the second most exported fruit from Colombia would result in a reduced impact on environment and economy. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  7. Evolutionary history of tall fescue morphotypes inferred from molecular phylogenetics of the Lolium-Festuca species complex

    Directory of Open Access Journals (Sweden)

    Stewart Alan V

    2010-10-01

    Full Text Available Abstract Background The agriculturally important pasture grass tall fescue (Festuca arundinacea Schreb. syn. Lolium arundinaceum (Schreb. Darbysh. is an outbreeding allohexaploid, that may be more accurately described as a species complex consisting of three major (Continental, Mediterranean and rhizomatous morphotypes. Observation of hybrid infertility in some crossing combinations between morphotypes suggests the possibility of independent origins from different diploid progenitors. This study aims to clarify the evolutionary relationships between each tall fescue morphotype through phylogenetic analysis using two low-copy nuclear genes (encoding plastid acetyl-CoA carboxylase [Acc1] and centroradialis [CEN], the nuclear ribosomal DNA internal transcribed spacer (rDNA ITS and the chloroplast DNA (cpDNA genome-located matK gene. Other taxa within the closely related Lolium-Festuca species complex were also included in the study, to increase understanding of evolutionary processes in a taxonomic group characterised by multiple inter-specific hybridisation events. Results Putative homoeologous sequences from both nuclear genes were obtained from each polyploid species and compared to counterparts from 15 diploid taxa. Phylogenetic reconstruction confirmed F. pratensis and F. arundinacea var. glaucescens as probable progenitors to Continental tall fescue, and these species are also likely to be ancestral to the rhizomatous morphotype. However, these two morphotypes are sufficiently distinct to be located in separate clades based on the ITS-derived data set. All four of the generated data sets suggest independent evolution of the Mediterranean and Continental morphotypes, with minimal affinity between cognate sequence haplotypes. No obvious candidate progenitor species for Mediterranean tall fescues were identified, and only two putative sub-genome-specific haplotypes were identified for this morphotype. Conclusions This study describes the first

  8. A role for human mitochondrial complex II in the production of reactive oxygen species in human skin

    Directory of Open Access Journals (Sweden)

    Alasdair Anderson

    2014-01-01

    Full Text Available The mitochondrial respiratory chain is a major generator of cellular oxidative stress, thought to be an underlying cause of the carcinogenic and ageing process in many tissues including skin. Previous studies of the relative contributions of the respiratory chain (RC complexes I, II and III towards production of reactive oxygen species (ROS have focussed on rat tissues and certainly not on human skin which is surprising as this tissue is regularly exposed to UVA in sunlight, a potent generator of cellular oxidative stress. In a novel approach we have used an array of established specific metabolic inhibitors and DHR123 fluorescence to study the relative roles of the mitochondrial RC complexes in cellular ROS production in 2 types of human skin cells. These include additional enhancement of ROS production by exposure to physiological levels of UVA. The effects within epidermal and dermal derived skin cells are compared to other tissue cell types as well as those harbouring a compromised mitochondrial status (Rho-zero A549. The results show that the complex II inhibitor, TTFA, was the only RC inhibitor to significantly increase UVA-induced ROS production in both skin cell types (P<0.05 suggesting that the role of human skin complex II in terms of influencing ROS production is more important than previously thought particularly in comparison to liver cells. Interestingly, two-fold greater maximal activity of complex II enzyme was observed in both skin cell types compared to liver (P<0.001. The activities of RC enzymes appear to decrease with increasing age and telomere length is correlated with ageing. Our study showed that the level of maximal complex II activity was higher in the MRC5/hTERT (human lung fibroblasts transfected with telomerase cells than the corresponding wild type cells (P=0.0012 which can be considered (in terms of telomerase activity as models of younger and older cells respectively.

  9. Environmental Conditions and Threatened and Endangered Species Populations near the Titain, Atlas, and Delta Launch Complexes, Cape Canaveral Air Station

    Science.gov (United States)

    Oddy, Donna M.; Stolen, Eric D.; Schmalzer, Paul A.; Hensley, Melissa A.; Hall, Patrice; Larson, Vickie L.; Turek, Shannon R.

    1999-01-01

    Launches of Delta, Atlas, and Titan rockets from Cape Canaveral Air Station (CCAS) have potential environmental effects. These could occur from direct impacts of launches or indirectly from habitat alterations. This report summarizes a three-year study (1995-1998) characterizing the environment, with particular attention to threatened and endangered species, near Delta, Atlas, and Titan launch facilities. Cape Canaveral has been modified by Air Force development and by 50 years of fire suppression. The dominant vegetation type around the Delta and Atlas launch complexes is coastal oak hammock forest. Oak scrub is the predominant upland vegetation type near the Titan launch complexes. Compositionally, these are coastal scrub communities that has been unburned for greater than 40 years and have developed into closed canopy, low-stature forests. Herbaceous vegetation around active and inactive facilities, coastal strand and dune vegetation near the Atlantic Ocean, and exotic vegetation in disturbed areas are common. Marsh and estuarine vegetation is most common west of the Titan complexes. Launch effects to vegetation include scorch, acid, and particulate deposition. Discernable, cumulative effects are limited to small areas near the launch complexes. Water quality samples were collected at the Titan, Atlas, and Delta launch complexes in September 1995 (wet season) and January 1996 (dry season). Samples were analyzed for heavy metals, chloride, total organic carbon, calcium, iron, magnesium, sodium, total alkalinity, pH, and conductivity. Differences between fresh, brackish, and saline surface waters were evident. The natural buffering capacity of the environment surrounding the CCAS launch complexes is adequate for neutralizing acid deposition in rainfall and launch deposition. Populations of the Florida Scrub-Jay (Aphelocoma coerulescens), a Federally- listed, threatened species, reside near the launch complexes. Thirty-seven to forty-one scrub-jay territories were

  10. Morphometric analysis to discriminate between species: The case of the Megalobulimus leucostoma complex

    Directory of Open Access Journals (Sweden)

    Victor Borda

    2014-10-01

    Full Text Available Plasticity of conchological characters had led to erroneous descriptions and the accumulation of synonyms making difficult the discrimination among species. The land snail genus Megalobulimus is an example of this problem. Megalobulimus leucostoma (Sowerby, 1835 has three subspecies which are difficult to differentiate by using the original descriptions. The aim of this paper is to discriminate among the subspecies of M. leucostoma by using morphometric and distribution analyses. Both provide substantial differences between M. l. leucostoma and M. l lacunosus that would not support the subspecies status of the former. Megalobulimus leucostoma weyrauchi fits into the great conchological variability of M. l .leucostoma; also the sympatric status between these two subspecies would not support the subspecies status of the former, and M. l. weyrauchi should be considered as part of M. l. leucostoma.

  11. Intensitas dan Luas Serangan Beberapa Isolat Fusarium oxysporum f.sp. zingiberi pada Jahe Gajah

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    Hermawati Cahyaningrum

    2017-07-01

    Full Text Available Ginger is one of the spices and medicinal commodities which is cultivated in Indonesia. One of the obstacles encountered in the cultivation of ginger is the rhizome rot disease which is mainly caused by Fusarium oxysporum Schlecht f.sp. zingiberi Trujillo. This study is aimed to know the growth ability and virulence level of the isolates on ginger rhizome and plants. The research was conducted in the laboratory and in the screen house by using Complete Random Design consisted of 10 treatments and 4 replications. The parameters observed were growth ability of F. oxysporum f.sp. zingiberi, rhizome rot disease symptoms, incubation period, extensive decay and weight difference of the rhizomes. The results showed that F. oxysporum f.sp. zingiberi which was stored for 4 years in sterile soil medium was still capable to cause damage to the rhizome and plants. Incubation periods of rhizome decay and plant symptoms were from 3 to 11.5 and 55.5 to 68.5 days, respectively. The most virulent isolate was MSO1 with extensive decay of rhizome and the wilting intensity were 108.95 mm2 dan 33.88%, respectively.   Intisari Jahe merupakan salah satu komoditas rempah dan obat yang banyak dibudidayakan di Indonesia. Salah satu kendala yang dihadapi dalam budidaya jahe adalah adanya gangguan penyakit busuk rimpang yang disebabkan (terutama oleh Fusarium oxysporum Schlecht f.sp. zingiberi Trujillo. Penelitian bertujuan untuk menguji daya tumbuh dan virulensi isolat F. oxysporum f.sp. zingiberi pada rimpang dan tanaman jahe gajah. Penelitian dilakukan di laboratorium dan di rumah kasa menggunakan Rancangan Acak Kelompok Lengkap (RAKL yang masing-masing terdiri dari 10 perlakuan dan 4 ulangan. Parameter yang diamati meliputi daya tumbuh F. oxysporum f.sp. zingiberi, gejala penyakit busuk rimpang, masa inkubasi, luas pembusukan dan selisih bobot basah rimpang. Hasil penelitian menunjukkan bahwa F. oxysporum f.sp. zingiberi yang telah di simpan 4 tahun dalam medium tanah

  12. Using mitochondrial and nuclear sequence data for disentangling population structure in complex pest species: a case study with Dermanyssus gallinae.

    Directory of Open Access Journals (Sweden)

    Lise Roy

    Full Text Available Among global changes induced by human activities, association of breakdown of geographical barriers and impoverishered biodiversity of agroecosystems may have a strong evolutionary impact on pest species. As a consequence of trade networks' expansion, secondary contacts between incipient species, if hybrid incompatibility is not yet reached, may result in hybrid swarms, even more when empty niches are available as usual in crop fields and farms. By providing important sources of genetic novelty for organisms to adapt in changing environments, hybridization may be strongly involved in the emergence of invasive populations. Because national and international trade networks offered multiple hybridization opportunities during the previous and current centuries, population structure of many pest species is expected to be the most intricate and its inference often blurred when using fast-evolving markers. Here we show that mito-nuclear sequence datasets may be the most helpful in disentangling successive layers of admixture in the composition of pest populations. As a model we used D. gallinae s. l., a mesostigmatid mite complex of two species primarily parasitizing birds, namely D. gallinae L1 and D. gallinae s. str. The latter is a pest species, considered invading layer farms in Brazil. The structure of the pest as represented by isolates from both wild and domestic birds, from European (with a focus on France, Australian and Brazilian farms, revealed past hybridization events and very recent contact between deeply divergent lineages. The role of wild birds in the dissemination of mites appears to be null in European and Australian farms, but not in Brazilian ones. In French farms, some recent secondary contact is obviously consecutive to trade flows. Scenarios of populations' history were established, showing five different combinations of more or less dramatic bottlenecks and founder events, nearly interspecific hybridizations and recent

  13. Estudio del antagonismo de algunas especies de Trichoderma sobre Fusarium Oxysporum y Rhizoctonia Solani Antagonism studies of Trichoderma sp.p.. with Fusarium oxysporum and Rhizoctonia solani

    Directory of Open Access Journals (Sweden)

    Elias Ricardo

    1989-12-01

    Full Text Available En este trabajo se estudió el antagonismo de algunos aislamientos del hongo Trichoderma obtenidos de suelos colornbianos en el control de Fusarium oxysporum y Rhizoctonia solani. En los ensayos "in vitre" se observó un marcado antagonismo entre las colonias de los aislamientos de Trichoderma sobre R. sotsni, con una reducción apreciable
    del tamaño de la colonia y un antaqonismo menor sobre F. oxysporum. En los ensayos de parasitismo a nivel microscópico, se observó una gran interacción entre alqunos
    de los aislamientos de T. harzianum y T. hamatum y el patógéno R. solani rnanifestado por el enrollamiento, penetración, fragmentación y lisis de las hifas del patoqeno.
    Los aislamientos de Trichoderma causaron un retraso en la aparición de los síntomas, una reducción en la severidad de la
    enfermedad. y un menor número de plantas enfermas ocasionadas por F. oxysporum f. sp, cucumerinum en pepino cohombro, y su efecto fue superior en todos los casos a la
    aplicación del fungicida benomil. Los aislamientos del antagonista aumentaron la qerminación de las semillas, la emergencia y el tamaño de las plántulas y redujeron la severidad de la enfermedad ocasionada por R. solani en fríjol.Several experiments were conducted to study the antagonism of 17 isolates of Trichoderma from Colombian soils with Fusarium oxysporum and Rhizoctonia solani. In "in vitro" tests, a high antagonism between colonies was found being greater the antagonism of Trichoderma with R. solani. At the microscopic level it was observed a great interaction between T. harzianum and T. hamatum with R. solani in such a way that the hyphae of the pathogen showed coiling, penetration, fragmentation and lysis. The Trichoderma isolates caused reduction in the disease severity, in the incubation period and a lower number of diseased cucumber plants when they were inoeulated with F. oxysporum f. sp, cucumerinum and these effects were better than Benomyl

  14. The F-box protein Fbp1 functions in the invasive growth and cell wall integrity mitogen-activated protein kinase (MAPK) pathways in Fusarium oxysporum.

    Science.gov (United States)

    Miguel-Rojas, Cristina; Hera, Concepcion

    2016-01-01

    F-box proteins determine substrate specificity of the ubiquitin-proteasome system. Previous work has demonstrated that the F-box protein Fbp1, a component of the SCF(Fbp1) E3 ligase complex, is essential for invasive growth and virulence of the fungal plant pathogen Fusarium oxysporum. Here, we show that, in addition to invasive growth, Fbp1 also contributes to vegetative hyphal fusion and fungal adhesion to tomato roots. All of these functions have been shown previously to require the mitogen-activated protein kinase (MAPK) Fmk1. We found that Fbp1 is required for full phosphorylation of Fmk1, indicating that Fbp1 regulates virulence and invasive growth via the Fmk1 pathway. Moreover, the Δfbp1 mutant is hypersensitive to sodium dodecylsulfate (SDS) and calcofluor white (CFW) and shows reduced phosphorylation levels of the cell wall integrity MAPK Mpk1 after SDS treatment. Collectively, these results suggest that Fbp1 contributes to both the invasive growth and cell wall integrity MAPK pathways of F. oxysporum. © 2015 BSPP AND JOHN WILEY & SONS LTD.

  15. Environmental Conditions and Threatened and Endangered Species Populations near the Titan, Atlas, and Delta Launch Complexes, Cape Canaveral Air Station

    Science.gov (United States)

    Oddy, Donna M.; Stolen, Eric D.; Schmalzer, Paul A.; Hensley, Melissa A.; Hall, Patrice; Larson, Vickie L.; Turek, Shannon R.

    1999-01-01

    Launches of Delta, Atlas, and Titan rockets from Cape Canaveral Air Station (CCAS) have potential environmental effects. These could occur from direct impacts of launches or indirectly from habitat alterations. This report summarizes a three-year study (1 995-1 998) characterizing the environment, with particular attention to threatened and endangered species, near Delta, Atlas, and Titan launch facilities. Cape Canaveral has been modified by Air Force development and by 50 years of fire suppression. The dominant vegetation type around the Delta and Atlas launch complexes is coastal oak hammock forest. Oak scrub is the predominant upland vegetation type near the Titan launch complexes. Compositionally, these are coastal scrub communities that has been unburned for > 40 years and have developed into closed canopy, low-stature forests. Herbaceous vegetation around active and inactive facilities, coastal strand and dune vegetation near the Atlantic Ocean, and exotic vegetation in disturbed areas are common. Marsh and estuarine vegetation is most common west of the Titan complexes. Launch effects to vegetation include scorch, acid, and particulate deposition. Discernable, cumulative effects are limited to small areas near the launch complexes. Water quality samples were collected at the Titan, Atlas, and Delta launch complexes in September 1995 (wet season) and January 1996 (dry season). Samples were analyzed for heavy metals, chloride, total organic carbon, calcium, iron, magnesium, sodium, total alkalinity, pH, and conductivity. Differences between fresh, brackish, and saline surface waters were evident. The natural buffering capacity of the environment surrounding the CCAS launch complexes is adequate for neutralizing acid deposition in rainfall and launch deposition. Populations of the Florida Scrub-Jay (Aphelocoma coerulescens), a Federally-listed, threatened species, reside near the launch complexes. Thirty-seven to forty-one scrub-jay territories were located at

  16. Simultaneous analysis of free and humic acid complexed europium and gadolinium species by CE-ICP-MS

    International Nuclear Information System (INIS)

    Kautenburger, R.; Nowotka, K.; Beck, H.P.

    2005-01-01

    -system it was possible to quantify metal concentrations from the detection limit up to approximately 1 ppm on a linear scale. This setup was used to separate metal / humic acid-species in a 10 mM acetic acid / 1 mM acetate buffer system. With humic acid as complexing ligand, free metal species could be separated from the metal-humate-complexes on a time resolved scale. The ratios of free metal ions and metal-humate- complexes are change with different experimental conditions like pH values or metal concentrations. This research is financially supported by the 'Bundesministerium fuer Wirtschaft und Arbeit' (BMWA, project 02E9683). (authors)

  17. The FTF gene family regulates virulence and expression of SIX effectors in Fusarium oxysporum.

    Science.gov (United States)

    Niño-Sánchez, Jonathan; Casado-Del Castillo, Virginia; Tello, Vega; De Vega-Bartol, José J; Ramos, Brisa; Sukno, Serenella A; Díaz Mínguez, José María

    2016-09-01

    The FTF (Fusarium transcription factor) gene family comprises a single copy gene, FTF2, which is present in all the filamentous ascomycetes analysed, and several copies of a close relative, FTF1, which is exclusive to Fusarium oxysporum. An RNA-mediated gene silencing system was developed to target mRNA produced by all the FTF genes, and tested in two formae speciales: F. oxysporum f. sp. phaseoli (whose host is common bean) and F. oxysporum f. sp. lycopersici (whose host is tomato). Quantification of the mRNA levels showed knockdown of FTF1 and FTF2 in randomly isolated transformants of both formae speciales. The attenuation of FTF expression resulted in a marked reduction in virulence, a reduced expression of several SIX (Secreted In Xylem) genes, the best studied family of effectors in F. oxysporum, and lower levels of SGE1 (Six Gene Expression 1) mRNA, the presumptive regulator of SIX expression. Moreover, the knockdown mutants showed a pattern of colonization of the host plant similar to that displayed by strains devoid of FTF1 copies (weakly virulent strains). Gene knockout of FTF2 also resulted in a reduction in virulence, but to a lesser extent. These results demonstrate the role of the FTF gene expansion, mostly the FTF1 paralogues, as a regulator of virulence in F. oxysporum and suggest that the control of effector expression is the mechanism involved. © 2016 The Authors Molecular Plant Pathology Published by British Society for Plant Pathology and John Wiley & Sons Ltd.

  18. Autophagy contributes to regulation of nuclear dynamics during vegetative growth and hyphal fusion in Fusarium oxysporum.

    Science.gov (United States)

    Corral-Ramos, Cristina; Roca, M Gabriela; Di Pietro, Antonio; Roncero, M Isabel G; Ruiz-Roldán, Carmen

    2015-01-01

    In the fungal pathogen Fusarium oxysporum, vegetative hyphal fusion triggers nuclear mitotic division in the invading hypha followed by migration of a nucleus into the receptor hypha and degradation of the resident nucleus. Here we examined the role of autophagy in fusion-induced nuclear degradation. A search of the F. oxysporum genome database for autophagy pathway components identified putative orthologs of 16 core autophagy-related (ATG) genes in yeast, including the ubiquitin-like protein Atg8, which is required for the formation of autophagosomal membranes. F. oxysporum Foatg8Δ mutants were generated in a strain harboring H1-cherry fluorescent protein (ChFP)-labeled nuclei to facilitate analysis of nuclear dynamics. The Foatg8Δ mutants did not show MDC-positive staining in contrast to the wild type and the FoATG8-complemented (cFoATG8) strain, suggesting that FoAtg8 is required for autophagy in F. oxysporum. The Foatg8Δ strains displayed reduced rates of hyphal growth, conidiation, and fusion, and were significantly attenuated in virulence on tomato plants and in the nonvertebrate animal host Galleria mellonella. In contrast to wild-type hyphae, which are almost exclusively composed of uninucleated hyphal compartments, the hyphae of the Foatg8Δ mutants contained a significant fraction of hyphal compartments with 2 or more nuclei. The increase in the number of nuclei per hyphal compartment was particularly evident after hyphal fusion events. Time-lapse microscopy analyses revealed abnormal mitotic patterns during vegetative growth in the Foatg8Δ mutants. Our results suggest that autophagy mediates nuclear degradation after hyphal fusion and has a general function in the control of nuclear distribution in F. oxysporum.

  19. Ethanol effect on metabolic activity of the ethalogenic fungus Fusarium oxysporum.

    Science.gov (United States)

    Paschos, Thomas; Xiros, Charilaos; Christakopoulos, Paul

    2015-03-12

    Fusarium oxysporum is a filamentous fungus which has attracted a lot of scientific interest not only due to its ability to produce a variety of lignocellulolytic enzymes, but also because it is able to ferment both hexoses and pentoses to ethanol. Although this fungus has been studied a lot as a cell factory, regarding applications for the production of bioethanol and other high added value products, no systematic study has been performed concerning its ethanol tolerance levels. In aerobic conditions it was shown that both the biomass production and the specific growth rate were affected by the presence of ethanol. The maximum allowable ethanol concentration, above which cells could not grow, was predicted to be 72 g/L. Under limited aeration conditions the ethanol-producing capability of the cells was completely inhibited at 50 g/L ethanol. The lignocellulolytic enzymatic activities were affected to a lesser extent by the presence of ethanol, while the ethanol inhibitory effect appears to be more severe at elevated temperatures. Moreover, when the produced ethanol was partially removed from the broth, it led to an increase in fermenting ability of the fungus up to 22.5%. The addition of F. oxysporum's system was shown to increase the fermentation of pretreated wheat straw by 11%, in co-fermentation with Saccharomyces cerevisiae. The assessment of ethanol tolerance levels of F. oxysporum on aerobic growth, on lignocellulolytic activities and on fermentative performance confirmed its biotechnological potential for the production of bioethanol. The cellulolytic and xylanolytic enzymes of this fungus could be exploited within the biorefinery concept as their ethanol resistance is similar to that of the commercial enzymes broadly used in large scale fermentations and therefore, may substantially contribute to a rational design of a bioconversion process involving F. oxysporum. The SSCF experiments on liquefied wheat straw rich in hemicellulose indicated that the

  20. Colonization of a Central Venous Catheter by the Hyaline Fungus Fusarium solani Species Complex: A Case Report and SEM Imaging

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    Alberto Colombo

    2013-01-01

    Full Text Available The incidence of opportunistic infections by filamentous fungi is increasing partly due to the widespread use of central venous catheters (CVC, indwelling medical devices, and antineoplastic/immunosuppressive drugs. The case of a 13-year-old boy under treatment for acute lymphoblastic leukemia is presented. The boy was readmitted to the Pediatric Ward for intermittent fever of unknown origin. Results of blood cultures drawn from peripheral venous sites or through the CVC were compared. CVC-derived bottles (but not those from peripheral veins yielded hyaline fungi that, based on morphology, were identified as belonging to the Fusarium solani species complex. Gene amplification and direct sequencing of the fungal ITS1 rRNA region and the EF-1alpha gene confirmed the isolate as belonging to the Fusarium solani species complex. Portions of the CVC were analyzed by scanning electron microscopy. Fungi mycelia with long protruding hyphae were seen into the lumen. The firm adhesion of the fungal formation to the inner surface of the catheter was evident. In the absence of systemic infection, catheter removal and prophylactic voriconazole therapy were followed by disappearance of febrile events and recovery. Thus, indwelling catheters are prone to contamination by environmental fungi.

  1. FUNGICIDAL PROPERTIES OF ARTEMISIA AROMATIC PLANTS TOWARDS FUSARIUM OXYSPORUM

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    Ivashchenko Iryna Vіctorovna

    2015-08-01

    Full Text Available The article establishes the fungicidal activity of water extracts of Artemisia maritimа L., Artemisia austriaca Jacq., under the concentration of 100, 50 and 25 mg/ml on dry matter with regard to the phytopathogenic mushroom Fusarium oxysporum. It also shows the fungistatic influence of extract of Artemisia dracunculus L. under concentration 25 and 50 mg/ml, fungicidal – under 100 mg/ml. Concerning Artemisia abrotanum L., the slow growth of mushroom is observed under the concentration 25 mg/ml, fungicidal effect – under 50 and 100 mg/ml. The paper provides the information on the component composition of ethereal oil and phenolic compounds of Artemisia maritimа, Artemisia austriaca, Artemisia abrotanum, Artemisia dracunculus, cultivated in Zhytomyr Polissya. The chief ingredients of ethereal oil which is synthesized by the plant of Artemisia abrotanum are 1,8-cineole (30.44% and camphor (31.92%. A high 1,8-cineole and camphor content determines antimicrobial properties of the plants. Amount of phenolic compounds in the air-dry raw Artemisia abrotanum is 2.98 percent. By the method of highly efficient solution chromatography (HESChr in the grass of Artemisia abrotanum we have detected 23 phenolic compounds, of which we identified such flavonoids as rutin, luteolin-7-glycoside as well as caffeic, chlorogenic and isochlorogenic acids. The main compounds of ethereal oil of Artemisia austriaca are trans-verbenole (30.77 %, pinocarvone (10.77 % and sabinilacetate (18.16 %. In the grass of Artemisia austriaca we have detected 31 phenolic compounds, of which we identified such flavonoids as rutin, apigenin, quercetin-bioside and the following acids: caffeic, chlorogenic, and isochlorogenic. Amount of phenolic compounds in the air-dry raw Austrian wormwood is 27.25 mg / g (2.73 %. The main component of ethereal oil of Artemisia dracunculus is methyleugenol (94.65 %. We have discovered 31 phenolic compounds in the grass of linear-leaved wormwood

  2. Multilocus phylogeny of the avian family Alaudidae (larks) reveals complex morphological evolution, non-monophyletic genera and hidden species diversity.

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    Alström, Per; Barnes, Keith N; Olsson, Urban; Barker, F Keith; Bloomer, Paulette; Khan, Aleem Ahmed; Qureshi, Masood Ahmed; Guillaumet, Alban; Crochet, Pierre-André; Ryan, Peter G

    2013-12-01

    The Alaudidae (larks) is a large family of songbirds in the superfamily Sylvioidea. Larks are cosmopolitan, although species-level diversity is by far largest in Africa, followed by Eurasia, whereas Australasia and the New World have only one species each. The present study is the first comprehensive phylogeny of the Alaudidae. It includes 83.5% of all species and representatives from all recognised genera, and was based on two mitochondrial and three nuclear loci (in total 6.4 kbp, although not all loci were available for all species). In addition, a larger sample, comprising several subspecies of some polytypic species was analysed for one of the mitochondrial loci. There was generally good agreement in trees inferred from different loci, although some strongly supported incongruences were noted. The tree based on the concatenated multilocus data was overall well resolved and well supported by the data. We stress the importance of performing single gene as well as combined data analyses, as the latter may obscure significant incongruence behind strong nodal support values. The multilocus tree revealed many unpredicted relationships, including some non-monophyletic genera (Calandrella, Mirafra, Melanocorypha, Spizocorys). The tree based on the extended mitochondrial data set revealed several unexpected deep divergences between taxa presently treated as conspecific (e.g. within Ammomanes cinctura, Ammomanes deserti, Calandrella brachydactyla, Eremophila alpestris), as well as some shallow splits between currently recognised species (e.g. Certhilauda brevirostris-C. semitorquata-C. curvirostris; Calendulauda barlowi-C. erythrochlamys; Mirafra cantillans-M. javanica). Based on our results, we propose a revised generic classification, and comment on some species limits. We also comment on the extraordinary morphological adaptability in larks, which has resulted in numerous examples of parallel evolution (e.g. in Melanocorypha mongolica and Alauda leucoptera [both

  3. Marennine, Promising Blue Pigments from a Widespread Haslea Diatom Species Complex

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    Romain Gastineau

    2014-05-01

    Full Text Available In diatoms, the main photosynthetic pigments are chlorophylls a and c, fucoxanthin, diadinoxanthin and diatoxanthin. The marine pennate diatom Haslea ostrearia has long been known for producing, in addition to these generic pigments, a water-soluble blue pigment, marennine. This pigment, responsible for the greening of oysters in western France, presents different biological activities: allelopathic, antioxidant, antibacterial, antiviral, and growth-inhibiting. A method to extract and purify marennine has been developed, but its chemical structure could hitherto not be resolved. For decades, H. ostrearia was the only organism known to produce marennine, and can be found worldwide. Our knowledge about H. ostrearia-like diatom biodiversity has recently been extended with the discovery of several new species of blue diatoms, the recently described H. karadagensis, H. silbo sp. inedit. and H. provincialis sp. inedit. These blue diatoms produce different marennine-like pigments, which belong to the same chemical family and present similar biological activities. Aside from being a potential source of natural blue pigments, H. ostrearia-like diatoms thus present a commercial potential for aquaculture, cosmetics, food and health industries.

  4. Postembryonic development of hard jaws (trophi) in a species belonging to the Brachionus plicatilis complex (Rotifera, Monogononta): a morphometric analysis.

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    Fontaneto, Diego; Melone, Giulio

    2006-04-01

    The presence of hard jaws (trophi), with species-specific shape and size, is a taxonomic feature of Rotifera, a group of microscopic metazoans. Since trophi are used to discriminate among species, it is important to know whether these structures change in taxonomically important ways during postembryonic development. Using both SEM and optical images, we analyzed more than 100 individuals of a single clonal lineage of a monogonont rotifer, Brachionus plicatilis, in order to describe body and trophi development after hatching. Body size, expressed as lorica width and length, was isometrically related to age of the animals only during preadult stages. Trophi size, expressed as length of the different parts, was unrelated to either age or body size. Therefore, trophi elements do not grow after hatching in B. plicatilis. Despite the dimensional invariance with age, some differences in trophi size among individuals of the same clone were recorded. No difference in left-right asymmetry of the trophi was shown; the asymmetric elements of the trophi named rami consistently had the right ramus longer than the left. This constancy is in contrast to the reported trophi asymmetries in bdelloid rotifers, in which left-right asymmetries are not constant within clonal lineages. In conclusion, we suggest that also trophi size, constant within the analyzed clone, may be used as an additional taxonomic feature to help in the discrimination of taxa within the B. plicatilis complex of cryptic species. Copyright (c) 2006 Wiley-Liss, Inc.

  5. Delineating ecological boundaries of Hanuman langur species complex in peninsular India using MaxEnt modeling approach.

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    Nag, Chetan; Chetan, Nag; Karanth, K Praveen; Praveen, Karanth K; Gururaja, Kotambylu Vasudeva; Vasudeva, Gururaja Kotambylu

    2014-01-01

    Hanuman langur is one of the widely distributed and extensively studied non-human diurnal primates in India. Until recently it was believed to be a single species - Semnopithecus entellus. Recent molecular and morphological studies suggest that the Hanuman langurs consists of at least three species S. entellus, S. hypoleucos and S. priam. Furthermore, morphological studies suggested that both S. hypoleucos and S. priam have at least three subspecies in each. We explored the use of ecological niche modeling (ENM) to confirm the validity of these seven taxa and an additional taxon S. johnii belonging to the same genus. MaxEnt modeling tool was used with 19 bioclimatic, 12 vegetation and 6 hydrological environmental layers. We reduced total environmental variables to 14 layers after testing for collinearity and an independent test for model prediction was done using ENMTools. A total of 196 non-overlapping data points from primary and secondary sources were used as inputs for ENM. Results showed eight distinct ecological boundaries, corroborating the eight taxa mentioned above thereby confirming validity of these eight taxa. The study, for the first time provided ecological variables that determined the ecological requirements and distribution of members of the Hanuman langur species complex in the Indian peninsula.

  6. Phylogeographic pattern and extensive mitochondrial DNA divergence disclose a species complex within the Chagas disease vector Triatoma dimidiata.

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    Fernando A Monteiro

    Full Text Available BACKGROUND: Triatoma dimidiata is among the main vectors of Chagas disease in Latin America. However, and despite important advances, there is no consensus about the taxonomic status of phenotypically divergent T. dimidiata populations, which in most recent papers are regarded as subspecies. METHODOLOGY AND FINDINGS: A total of 126 cyt b sequences (621 bp long were produced for specimens from across the species range. Forty-seven selected specimens representing the main cyt b clades observed (after a preliminary phylogenetic analysis were also sequenced for an ND4 fragment (554 bp long and concatenated with their respective cyt b sequences to produce a combined data set totalling 1175 bp/individual. Bayesian and Maximum-Likelihood phylogenetic analyses of both data sets (cyt b, and cyt b+ND4 disclosed four strongly divergent (all pairwise Kimura 2-parameter distances >0.08, monophyletic groups: Group I occurs from Southern Mexico through Central America into Colombia, with Ecuadorian specimens resembling Nicaraguan material; Group II includes samples from Western-Southwestern Mexico; Group III comprises specimens from the Yucatán peninsula; and Group IV consists of sylvatic samples from Belize. The closely-related, yet formally recognized species T. hegneri from the island of Cozumel falls within the divergence range of the T. dimidiata populations studied. CONCLUSIONS: We propose that Groups I-IV, as well as T. hegneri, should be regarded as separate species. In the Petén of Guatemala, representatives of Groups I, II, and III occur in sympatry; the absence of haplotypes with intermediate genetic distances, as shown by multimodal mismatch distribution plots, clearly indicates that reproductive barriers actively promote within-group cohesion. Some sylvatic specimens from Belize belong to a different species - likely the basal lineage of the T. dimidiata complex, originated ~8.25 Mya. The evidence presented here strongly supports the proposition

  7. Cryptic or pseudocryptic: can morphological methods inform copepod taxonomy? An analysis of publications and a case study of the Eurytemora affinis species complex

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    Lajus, Dmitry; Sukhikh, Natalia; Alekseev, Victor

    2015-01-01

    Interest in cryptic species has increased significantly with current progress in genetic methods. The large number of cryptic species suggests that the resolution of traditional morphological techniques may be insufficient for taxonomical research. However, some species now considered to be cryptic may, in fact, be designated pseudocryptic after close morphological examination. Thus the “cryptic or pseudocryptic” dilemma speaks to the resolution of morphological analysis and its utility for identifying species. We address this dilemma first by systematically reviewing data published from 1980 to 2013 on cryptic species of Copepoda and then by performing an in-depth morphological study of the former Eurytemora affinis complex of cryptic species. Analyzing the published data showed that, in 5 of 24 revisions eligible for systematic review, cryptic species assignment was based solely on the genetic variation of forms without detailed morphological analysis to confirm the assignment. Therefore, some newly described cryptic species might be designated pseudocryptic under more detailed morphological analysis as happened with Eurytemora affinis complex. Recent genetic analyses of the complex found high levels of heterogeneity without morphological differences; it is argued to be cryptic. However, next detailed morphological analyses allowed to describe a number of valid species. Our study, using deep statistical analyses usually not applied for new species describing, of this species complex confirmed considerable differences between former cryptic species. In particular, fluctuating asymmetry (FA), the random variation of left and right structures, was significantly different between forms and provided independent information about their status. Our work showed that multivariate statistical approaches, such as principal component analysis, can be powerful techniques for the morphological discrimination of cryptic taxons. Despite increasing cryptic species

  8. Iron-complexed adsorptive membrane for As(V) species in water

    International Nuclear Information System (INIS)

    Shinde, Rakesh N.; Das, Sadananda; Acharya, R.; Rajurkar, N.S.; Pandey, Ashok K.

    2012-01-01

    Highlights: ► Functionalized membrane was prepared by graft polymerization in host membrane. ► Fe 3+ ions fixed in membrane made it selective for As(V) ions. ► As(V) preconcentrated selectively in membrane samples was quantified by INAA. ► As(V) in ground water sample was easily quantified in 2–3 ppb using membrane. ► Total inorganic arsenic could be quantified by oxidation of As(III) to As(V). - Abstract: Selective preconcentration of a target analyte in the solid phase is an effective route not only to enhance detection limit of the conventional analytical method but also for elimination of interfering matrix. An adsorptive membrane was developed for selective preconcentration and quantification of ultra-trace (ppb) amounts of As(V) present in a variety of aqueous samples. The precursor membrane was prepared by UV-initiator induced graft polymerization of sulphate and phosphate bearing monomers (1:1 mol proportion) in pores of the host microporous poly(propylene) membrane. Fe 3+ ions were loaded in the precursor membrane to make it selective for As(V) ions. The presence of phosphate functional groups prevent leaching of Fe 3+ ions from the membrane when it comes in contact with solution like seawater having high ionic strength. The optimized membrane was characterized in terms of its physical structure, chemical structure and experimental conditions affecting As(V) uptake in the membrane. The possibility of quantifying total preconcentration of As content was also explored by converting As(III) to As(V). To quantify As(V), the membrane samples were subjected to instrumental neutron activation analysis (INAA). The studies carried in the present work showed that quantification of inorganic arsenic species in natural water samples is easily possible in 2–3 ppb concentration range.

  9. Genetic complexity and multiple infections with more Parvovirus species in naturally infected cats

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    Battilani Mara

    2011-03-01

    Full Text Available Abstract Parvoviruses of carnivores include three closely related autonomous parvoviruses: canine parvovirus (CPV, feline panleukopenia virus (FPV and mink enteritis virus (MEV. These viruses cause a variety of serious diseases, especially in young patients, since they have a remarkable predilection for replication in rapidly dividing cells. FPV is not the only parvovirus species which infects cats; in addition to MEV, the new variants of canine parvovirus, CPV-2a, 2b and 2c have also penetrated the feline host-range, and they are able to infect and replicate in cats, causing diseases indistinguishable from feline panleukopenia. Furthermore, as cats are susceptible to both CPV-2 and FPV viruses, superinfection and co-infection with multiple parvovirus strains may occur, potentially facilitating recombination and high genetic heterogeneity. In the light of the importance of cats as a potential source of genetic diversity for parvoviruses and, since feline panleukopenia virus has re-emerged as a major cause of mortality in felines, the present study has explored the molecular characteristics of parvovirus strains circulating in cat populations. The most significant findings reported in this study were (a the detection of mixed infection FPV/CPV with the presence of one parvovirus variant which is a true intermediate between FPV/CPV and (b the quasispecies cloud size of one CPV sample variant 2c. In conclusion, this study provides new important results about the evolutionary dynamics of CPV infections in cats, showing that CPV has presumably started a new process of readaptation in feline hosts.

  10. Ecomorph or endangered coral? DNA and microstructure reveal hawaiian species complexes: Montipora dilatata/flabellata/turgescens & M. patula/verrilli.

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    Zac H Forsman

    2010-12-01

    Full Text Available M. dilatata, M. flabellata, and M. patula and 80 other scleractinian corals were petitioned to be listed under the US Endangered Species Act (ESA, which would have major conservation implications. One of the difficulties with this evaluation is that reproductive boundaries between morphologically defined coral species are often permeable, and morphology can be wildly variable. We examined genetic and morphological variation in Hawaiian Montipora with a suite of molecular markers (mitochondrial: COI, CR, Cyt-B, 16S, ATP6; nuclear: ATPsβ, ITS and microscopic skeletal measurements. Mitochondrial markers and the ITS region revealed four distinct clades: I M. patula/M. verrilli, II M. cf. incrassata, III M. capitata, IV M. dilatata/M. flabellata/M. cf. turgescens. These clades are likely to occur outside of Hawai'i according to mitochondrial control region haplotypes from previous studies. The ATPsβ intron data showed a pattern often interpreted as resulting from hybridization and introgression; however, incomplete lineage sorting may be more likely since the multicopy nuclear ITS region was consistent with the mitochondrial data. Furthermore, principal components analysis (PCA of skeletal microstructure was concordant with the mitochondrial clades, while nominal taxa overlapped. The size and shape of verrucae or papillae contributed most to identifying groups, while colony-level morphology was highly variable. It is not yet clear if these species complexes represent population-level variation or incipient speciation (CA<1MYA, two alternatives that have very different conservation implications. This study highlights the difficulty in understanding the scale of genetic and morphological variation that corresponds to species as opposed to population-level variation, information that is essential for conservation and for understanding coral biodiversity.

  11. Drifter, a novel, low copy hAT-like transposon in Fusarium oxysporum is activated during starvation.

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    Rep, Martijn; van der Does, H Charlotte; Cornelissen, Ben J C

    2005-06-01

    The facultative pathogenic fungus Fusarium oxysporum is known to harbour many different transposable and/or repetitive elements. We have identified Drifter, a novel DNA transposon of the hAT family in F. oxysporum. It was found adjoining SIX1-H, a truncated homolog of the SIX1 avirulence gene in F. oxysporum f. sp. lycopersici. Absence of a target site duplication as well as the 5' part of SIX1-H suggests that transposition of Drifter into the ancestor of SIX1-H was followed by loss of a chromosomal segment through recombination between Drifters. F. oxysporum isolates belonging to various formae speciales harbour between 0 and 5 full-length copies of Drifter and/or one or more copies with an internal deletion. Transcription of Drifter is activated during starvation for carbon or nitrogen.

  12. Modeling of catalytically active metal complex species and intermediates in reactions of organic halides electroreduction.

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    Lytvynenko, Anton S; Kolotilov, Sergey V; Kiskin, Mikhail A; Eremenko, Igor L; Novotortsev, Vladimir M

    2015-02-28

    The results of quantum chemical modeling of organic and metal-containing intermediates that occur in electrocatalytic dehalogenation reactions of organic chlorides are presented. Modeling of processes that take place in successive steps of the electrochemical reduction of representative C1 and C2 chlorides - CHCl3 and Freon R113 (1,1,2-trifluoro-1,2,2-trichloroethane) - was carried out by density functional theory (DFT) and second-order Møller-Plesset perturbation theory (MP2). It was found that taking solvation into account using an implicit solvent model (conductor-like screening model, COSMO) or considering explicit solvent molecules gave similar results. In addition to modeling of simple non-catalytic dehalogenation, processes with a number of complexes and their reduced forms, some of which were catalytically active, were investigated by DFT. Complexes M(L1)2 (M = Fe, Co, Ni, Cu, Zn, L1H = Schiff base from 2-pyridinecarbaldehyde and the hydrazide of 4-pyridinecarboxylic acid), Ni(L2) (H2L2 is the Schiff base from salicylaldehyde and 1,2-ethylenediamine, known as salen) and Co(L3)2Cl2, representing a fragment of a redox-active coordination polymer [Co(L3)Cl2]n (L3 is the dithioamide of 1,3-benzenedicarboxylic acid), were considered. Gradual changes in electronic structure in a series of compounds M(L1)2 were observed, and correlations between [M(L1)2](0) spin-up and spin-down LUMO energies and the relative energies of the corresponding high-spin and low-spin reduced forms, as well as the shape of the orbitals, were proposed. These results can be helpful for determination of the nature of redox-processes in similar systems by DFT. No specific covalent interactions between [M(L1)2](-) and the R113 molecule (M = Fe, Co, Ni, Zn) were found, which indicates that M(L1)2 electrocatalysts act rather like electron transfer mediators via outer-shell electron transfer. A relaxed surface scan of the adducts {M(L1)2·R113}(-) (M = Ni or Co) versus the distance between the

  13. Evolutionary Genetic Analysis Uncovers Multiple Species with Distinct Habitat Preferences and Antibiotic Resistance Phenotypes in the Stenotrophomonas maltophilia Complex

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    Luz E. Ochoa-Sánchez

    2017-08-01

    Full Text Available The genus Stenotrophomonas (Gammaproteobacteria has a broad environmental distribution. Stenotrophomonas maltophilia is its best known species because it is a globally emerging, multidrug-resistant (MDR, opportunistic pathogen. Members of this species are known to display high genetic, ecological and phenotypic diversity, forming the so-called S. maltophilia complex (Smc. Heterogeneous resistance and virulence phenotypes have been reported for environmental Smc isolates of diverse ecological origin. We hypothesized that this heterogeneity could be in part due to the potential lumping of several cryptic species in the Smc. Here we used state-of-the-art phylogenetic and population genetics methods to test this hypothesis based on the multilocus dataset available for the genus at pubmlst.org. It was extended with sequences from complete and draft genome sequences to assemble a comprehensive set of reference sequences. This framework was used to analyze 108 environmental isolates obtained in this study from the sediment and water column of four rivers and streams in Central Mexico, affected by contrasting levels of anthropogenic pollution. The aim of the study was to identify species in this collection, defined as genetically cohesive sequence clusters, and to determine the extent of their genetic, ecological and phenotypic differentiation. The multispecies coalescent, coupled with Bayes factor analysis was used to delimit species borders, together with population genetic structure analyses, recombination and gene flow estimates between sequence clusters. These analyses consistently revealed that the Smc contains at least 5 significantly differentiated lineages: S. maltophilia and Smc1 to Smc4. Only S. maltophilia was found to be intrinsically MDR, all its members expressing metallo-β-lactamases (MBLs. The other Smc lineages were not MDR and did not express MBLs. We also obtained isolates related to S. acidaminiphila, S. humi and S. terrae. They

  14. Two new species of sympatric Fergusonina flies (Diptera: Fergusoninidae) from bud galls on high elevation snow gums (Eucalyptus pauciflora Sieb. ex Spreng. complex) in the Australian Alps

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    Two species of Fergusonina Malloch fly, F. daviesae Nelson sp.n. and F. taylori Nelson sp.n. (Diptera: Fergusoninidae), are described from terminal leaf bud galls on high elevation snow gums (Eucalyptus pauciflora complex) in the Australian Alps. These species occur in sympatry at the six locations...

  15. Identifikasi Ras Fisiologis Fusarium oxysporum f.sp. cubense Berdasarkan Sifat Kompatibel Secara Vegetatif dan Pembentukan Bahan Volatil

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    Arif Wibowo

    2002-07-01

    Full Text Available Race characterization of F. oxysporum Schlecht. f.sp. cubense (E.F. Smith Snyd. & Hans. by determining disease reaction is difficult because the result may be biased due to the variability of growing condition. This study is aimed to identify physiological races of F. oxysporum f.sp. cubense in banana plantation in the province of Daerah Istimewa Yogyakarta by examining the relation of the fungal pathogen isolates. The identification of physiological races of F. oxysporum f.sp. cubense was based on vegetative compatibility groups (VCGs. The research was conducted in The Laboratory of Mycology Faculty of Agriculture GMU on March to November 2000. Observation of heterokarion formed by the mutant of F. oxysporum f.sp. cubense on selective medium was carried out in order to identify the compatibility of two different fungal isolates. Nitrate non utilizing (nit mutants obtained without mutagen were used as the label. Nit mutant obtained from the same wild type isolates could form heterokarion on minimal agar medium containing NaNO3 as nitrogen source. Eleven isolates of F. oxysporum f.sp. cubense have been isolated from several cultivars of banana. Vegetative compatibility tests showed that of 11 eleven isolates, there were six different group VCGs where four of them formed volatile compound in rice medium whereas two of them did not. Key words: Fusarium wilt, F. oxysporum f.sp. cubense, vegetative compatibility groups (VCGs

  16. Infection Courts in Watermelon Plants Leading to Seed Infestation by Fusarium oxysporum f. sp. niveum.

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    Petkar, Aparna; Ji, Pingsheng

    2017-07-01

    Fusarium wilt incited by Fusarium oxysporum f. sp. niveum is a seed-transmitted disease that causes significant yield loss in watermelon production. The pathogen may infect watermelon seeds latently, which can be an important inoculum source and contribute to severe disease outbreak. However, information regarding infection courts of F. oxysporum f. sp. niveum leading to infestation of watermelon seeds is limited. To determine how seeds in watermelon fruit can be infested by F. oxysporum f. sp. niveum during the watermelon growing season, greenhouse and field experiments were conducted in 2014 and 2015 where watermelon flowers and immature fruit were inoculated with F. oxysporum f. sp. niveum. Seeds were extracted from mature watermelon fruit, and infestation of watermelon seeds was determined by isolation of F. oxysporum f. sp. niveum and further confirmed by real-time polymerase chain reaction (PCR) analysis. Inoculation of the pericarp of immature fruit resulted in 17.8 to 54.4% of infested seeds under field conditions and 0.6 to 12.8% of infested seeds under greenhouse conditions when seeds were not surface disinfested prior to isolation. Seed infestation was also detected in 0 to 4.5% of the seeds when seeds were surface disinfested prior to isolation. Inoculation of pistil resulted in 0 to 7.2% and 0 to 18.3% of infested seeds under greenhouse and field conditions when seeds were surface disinfested or not disinfested before isolation, respectively. Inoculation of peduncle resulted in 0.6 to 6.1% and 0 to 10.0% of infested seeds in the greenhouse and field experiments when seeds were surface disinfested or not disinfested before isolation, respectively. Seed infestation was also detected in all the experiments using real-time PCR assay when pericarp or pistil was inoculated, and in three of four experiments when peduncle was inoculated, regardless of whether seeds were surface disinfested or not disinfested. Pericarp and peduncle of immature watermelon fruit

  17. Organic complexation and translocation of ferric iron in podzols of the Negro River watershed. Separation of secondary Fe species from Al species

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    Fritsch, E.; Allard, Th.; Benedetti, M. F.; Bardy, M.; do Nascimento, N. R.; Li, Y.; Calas, G.

    2009-04-01

    The development of podzols in lateritic landscapes of the upper Amazon basin contributes to the exportation of organic carbon and associated metals in the black waters of the Negro River watershed. We have investigated the distribution of Fe III in the clay-size fraction of eight organic-rich horizons of waterlogged plateau podzols, to unravel the weathering conditions and mechanisms that control its transfer to the rivers. The speciation and amount of Fe III stored in residual mineral phases of laterites, or bound to organic compounds of weakly and well-expressed podzols, were determined by electron paramagnetic resonance spectroscopy combined with chemical analyses. Reducing conditions restrict the production of organo-Fe complexes in the subsoil B-horizons of waterlogged podzols and most of the Fe 2+ released from the dissolution of Fe-oxides is exported to the rivers via the perched groundwater. However, significant amounts of diluted Fe III bound to organic ligands (Fe IIIOM) and nano Fe-oxides are produced at the margin of the depression in the topsoil A horizons of weakly expressed podzols due to shorter periods of anoxia. The downward translocation of organically bound metals from topsoil A to subsoil B-horizons of podzols occurs in shorter distances for Fe than it does for Al. This separation of secondary Fe species from Al species is attributed to the physical fractionation of their organic carriers in texture contrasted B-horizons of podzols, as well as to the effect of pH on metal speciation in soil solutions and metal binding onto soil organic ligands (mostly for Al). This leads us to consider the topsoil A horizons of weakly expressed podzols, as well as the subsoil Bh horizon of better-expressed ones, as the main sources for the transfer of Fe IIIOM to the rivers. The concentration of Fe IIIOM rises from soil sources to river colloids, suggesting drastic biogeochemical changes in more oxygenated black waters of the Negro River watershed. The

  18. Genome-wide macrosynteny among Fusarium species in the Gibberella fujikuroi complex revealed by amplified fragment length polymorphisms.

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    Lieschen De Vos

    Full Text Available The Gibberella fujikuroi complex includes many Fusarium species that cause significant losses in yield and quality of agricultural and forestry crops. Due to their economic importance, whole-genome sequence information has rapidly become available for species including Fusarium circinatum, Fusarium fujikuroi and Fusarium verticillioides, each of which represent one of the three main clades known in this complex. However, no previous studies have explored the genomic commonalities and differences among these fungi. In this study, a previously completed genetic linkage map for an interspecific cross between Fusarium temperatum and F. circinatum, together with genomic sequence data, was utilized to consider the level of synteny between the three Fusarium genomes. Regions that are homologous amongst the Fusarium genomes examined were identified using in silico and pyrosequenced amplified fragment length polymorphism (AFLP fragment analyses. Homology was determined using BLAST analysis of the sequences, with 777 homologous regions aligned to F. fujikuroi and F. verticillioides. This also made it possible to assign the linkage groups from the interspecific cross to their corresponding chromosomes in F. verticillioides and F. fujikuroi, as well as to assign two previously unmapped supercontigs of F. verticillioides to probable chromosomal locations. We further found evidence of a reciprocal translocation between the distal ends of chromosome 8 and 11, which apparently originated before the divergence of F. circinatum and F. temperatum. Overall, a remarkable level of macrosynteny was observed among the three Fusarium genomes, when comparing AFLP fragments. This study not only demonstrates how in silico AFLPs can aid in the integration of a genetic linkage map to the physical genome, but it also highlights the benefits of using this tool to study genomic synteny and architecture.

  19. Native trees of the Northeast Argentine: natural hosts of the Cryptococcus neoformans-Cryptococcus gattii species complex.

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    Cattana, Maria Emilia; Sosa, María de Los Ángeles; Fernández, Mariana; Rojas, Florencia; Mangiaterra, Magdalena; Giusiano, Gustavo

    2014-01-01

    In Argentina, information about epidemiology and environmental distribution of Cryptococcus is scarce. The city of Resistencia borders with Brazil and Paraguay where this fungus is endemic. All these supported the need to investigate the ecology of the genus and the epidemiology of cryptococcosis in this area. The aim was to investigate the presence of species of Cryptococcus neoformans-Cryptococcus gattii complex and their genotypes in trees of the city of Resistencia. One hundred and five trees were sampled by swabbing technique. The isolates were identified using conventional and commercial methods and genotyped by PCR-RFLP (Restriction Fragment Length Polymorphism). Cryptococcus was found in 7 out of the total trees. 6 out of 7 Cryptococcus isolates were identified as C. neoformans and one as C. gattii. C. gattii was isolated from Grevillea robusta. C. neoformans strains were isolated from Tabebuia avellanedae and Peltophorum dubium. Genotyping showed that all C. neoformans belonged to the VNI type and C. gattii belonged to the VGI type. This represents the first study on the ecology of Cryptococcus spp. associated to trees from northeastern Argentina, and the first report describing Grevillea robusta as a host of members of this fungal genus. Another finding is the isolation of C. neoformans from Tabebuia avellanedae and Peltophorum dubium, both tree species native to northeastern Argentina. Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  20. Synergistic toxicity of Macondo crude oil and dispersant Corexit 9500A(®) to the Brachionus plicatilis species complex (Rotifera).

    Science.gov (United States)

    Rico-Martínez, Roberto; Snell, Terry W; Shearer, Tonya L

    2013-02-01

    Using the marine rotifer Brachionus plicatilis acute toxicity tests, we estimated the toxicity of Corexit 9500A(®), propylene glycol, and Macondo oil. Ratios of 1:10, 1:50 and 1:130 for Corexit 9500A(®):Macondo oil mixture represent: maximum exposure concentrations, recommended ratios for deploying Corexit (1:10-1:50), 1:130 the actual dispersant:oil ratio used in the Deep Water Horizon spill. Corexit 9500A(®) and oil are similar in their toxicity. However, when Corexit 9500A(®) and oil are mixed, toxicity to B. manjavacas increases up to 52-fold. Extrapolating these results to the oil released by the Macondo well, suggests underestimation of increased toxicity from Corexit application. We found small differences in sensitivity among species of the B. plicatilis species complex, likely reflecting phylogenetic similarity. Just 2.6% of the water-accommodated fraction of oil inhibited rotifer cyst hatching by 50%, an ecologically significant result because rotifer cyst in sediments are critical resources for the recolonization of populations each Spring. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Re-evaluation of the Helichrysum italicum complex (Compositae: Gnaphalieae: A new species from Majorca (Balearic Islands

    Directory of Open Access Journals (Sweden)

    S. Herrando-Moraira

    2016-09-01

    Full Text Available Helichrysum italicum is a widely distributed species in the Mediterranean Basin, which has received controversial taxonomic treatments at infraspecific level owing to its morphological variability. In this paper we perform a detailed multivariate analysis of morphological characters using an exhaustive sampling of H. italicum. Integrating previously published molecular, chorological and newly obtained morphological data, a revised taxonomic treatment for the whole H. italicum complex is provided. On the one hand, the results obtained suggest that the Majorcan mountain populations of H. italicum subsp. microphyllum need to be considered an independent species, newly described here as Helichrysum massanellanum. On the other hand, H. italicum subspecies are recircumscribed. A new combination is proposed, H. italicum subsp. tyrrhenicum, a taxon that comprises populations from Corsica, Sardinia, Majorca coastline and Dragonera islet, whereas subsp. microphyllum is restricted to the island of Crete. With those substantial classification modifications, a complete new taxonomic treatment is presented for this group, including an identification key, synonyms, morphological descriptions, distribution areas and habitat characterization.

  2. Taxonomic changes and description of two new species for the Phyllodactylus lanei complex (Gekkota: Phyllodactylidae) in Mexico.

    Science.gov (United States)

    RamÍrez-Reyes, Tonatiuh; Flores-Villela, Oscar

    2018-04-10

    An integrative taxonomy approach was implemented based on analysis of genetic, phylogenetic, morphological and ecological data to identify the cryptic diversity within the Phyllodactylus lanei complex. At least six species can be identified, of which four are currently considered subspecies: Phyllodactylus lanei, Phyllodactylus rupinus, Phyllodactylus isabelae, Phyllodactylus lupitae and two corresponding to undescribed taxa, which are identified and described in this contribution. These differ from other Mexican geckos in several characters: genetic distance (DNAmt), position in molecular phylogeny (concatened data DNAmt+DNAnu), species tree, morphological characters such as snout-vent length, longitudinal scales, tubercles from head to tail, interorbital scales, scales across venter, third labial-snout scales and rows of tubercles across dorsum; there are also differences in their bioclimatic profiles (temperature and precipitation) and geographical distribution. The most recent studies on taxonomy and evolution of Mexican geckos (Phyllodactylus) show that the diversity of this group of reptiles is currently underestimated, suggesting that more research and conservation efforts are should be addressed at these lizards.

  3. Selection, trans-species polymorphism, and locus identification of major histocompatibility complex class IIβ alleles of New World ranid frogs

    Science.gov (United States)

    Kiemnec-Tyburczy, Karen M.; Richmond, Jonathan Q.; Savage, Anna E.; Zamudio, Kelly R.

    2010-01-01

    Genes encoded by the major histocompatibility complex (MHC) play key roles in the vertebrate immune system. However, our understanding of the evolutionary processes and underlying genetic mechanisms shaping these genes is limited in many taxa, including amphibians, a group currently impacted by emerging infectious diseases. To further elucidate the evolution of the MHC in frogs (anurans) and develop tools for population genetics, we surveyed allelic diversity of the MHC class II ??1 domain in both genomic and complementary DNA of seven New World species in the genus Rana (Lithobates). To assign locus affiliation to our alleles, we used a "gene walking" technique to obtain intron 2 sequences that flanked MHC class II?? exon 2. Two distinct intron sequences were recovered, suggesting the presence of at least two class II?? loci in Rana. We designed a primer pair that successfully amplified an orthologous locus from all seven Rana species. In total, we recovered 13 alleles and documented trans-species polymorphism for four of the alleles. We also found quantitative evidence of selection acting on amino acid residues that are putatively involved in peptide binding and structural stability of the ??1 domain of anurans. Our results indicated that primer mismatch can result in polymerase chain reaction (PCR) bias, which influences the number of alleles that are recovered. Using a single locus may minimize PCR bias caused by primer mismatch, and the gene walking technique was an effective approach for generating single-copy orthologous markers necessary for future studies of MHC allelic variation in natural amphibian populations. ?? 2010 Springer-Verlag.

  4. Population Dynamics Among six Major Groups of the Oryza rufipogon Species Complex, Wild Relative of Cultivated Asian Rice.

    Science.gov (United States)

    Kim, HyunJung; Jung, Janelle; Singh, Namrata; Greenberg, Anthony; Doyle, Jeff J; Tyagi, Wricha; Chung, Jong-Wook; Kimball, Jennifer; Hamilton, Ruaraidh Sackville; McCouch, Susan R

    2016-12-01

    Understanding population structure of the wild progenitor of Asian cultivated rice (O. sativa), the Oryza rufipogon species complex (ORSC), is of interest to plant breeders and contributes to our understanding of rice domestication. A collection of 286 diverse ORSC accessions was evaluated for nuclear variation using genotyping-by-sequencing (113,739 SNPs) and for chloroplast variation using Sanger sequencing (25 polymorphic sites). Six wild subpopulations were identified, with 25 % of accessions classified as admixed. Three of the wild groups were genetically and geographically closely related to the O. sativa subpopulations, indica, aus and japonica, and carried O. sativa introgressions; the other three wild groups were genetically divergent, had unique chloroplast haplotypes, and were located at the geographical extremes of the species range. The genetic subpopulations were significantly correlated (r 2  = 0.562) with traditional species designations, O. rufipogon (perennial) and O. nivara (annual), differentiated based on morphology and life history. A wild diversity panel of 95 purified (inbred) accessions was developed for future genetic studies. Our results suggest that the cultivated aus subpopulation is most closely related to an annual wild relative, japonica to a perennial wild relative, and indica to an admixed population of diverse annual and perennial wild ancestors. Gene flow between ORSC and O. sativa is common in regions where rice is cultivated, threatening the identity and diversity of wild ORSC populations. The three geographically isolated ORSC populations harbor variation rarely seen in cultivated rice and provide a unique window into the genetic composition of ancient rice subpopulations.

  5. Electrochemical and spectroscopic studies of the complexed species of models of nitrohumic acids derived from phthalic acid

    Directory of Open Access Journals (Sweden)

    Mercê Ana Lucia Ramalho

    1998-01-01

    Full Text Available The study of model compounds is necessary in order to obtain information about complex organic substances as in the case of humic substances (HS. These substances are potential organic fertilizers and have other important functions in soils, natural waters and organic sediments. The main chemical properties of the complexes formed from 3-nitrophthalic and 4-nitrophthalic acids and the metal ions Fe(III and Zn(II were studied using potentiometric titrations, ultraviolet-visible spectroscopy (UV-Vis and cyclic voltammetry (CV. A trial potentiometric titration was done with a mixture of the models for nitrohumic acids and Cu(II. Equilibrium constants for the systems were calculated and UV-Vis and CV were employed to monitor the formation of the species. Comparative studies involving chelating centres of nitrosalicylic acids and nitrocatechols with Fe(III, Zn(II and Cu(II are presented. The initial studies involving the nitrohumic substances (NHS, a laboratory artifact of HS have been made and good evidence was found for the further use of NHS as a potential organic fertilizer as well as HS. In this present work one of the observed advantages of NHS over HS was that some aromatic nitro- centres can bind some metal ions at p[H] values of normal soils, near 7.0 to 7.5.

  6. Sampling genetic diversity in the sympatrically and allopatrically speciating Midas cichlid species complex over a 16 year time series

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    Bunje Paul ME

    2007-02-01

    Full Text Available Abstract Background Speciation often occurs in complex or uncertain temporal and spatial contexts. Processes such as reinforcement, allopatric divergence, and assortative mating can proceed at different rates and with different strengths as populations diverge. The Central American Midas cichlid fish species complex is an important case study for understanding the processes of speciation. Previous analyses have demonstrated that allopatric processes led to species formation among the lakes of Nicaragua as well as sympatric speciation that is occurring within at least one crater lake. However, since speciation is an ongoing process and sampling genetic diversity of such lineages can be biased by collection scheme or random factors, it is important to evaluate the robustness of conclusions drawn on individual time samples. Results In order to assess the validity and reliability of inferences based on different genetic samples, we have analyzed fish from several lakes in Nicaragua sampled at three different times over 16 years. In addition, this time series allows us to analyze the population genetic changes that have occurred between lakes, where allopatric speciation has operated, as well as between different species within lakes, some of which have originated by sympatric speciation. Focusing on commonly used genetic markers, we have analyzed both DNA sequences from the complete mitochondrial control region as well as nuclear DNA variation at ten microsatellite loci from these populations, sampled thrice in a 16 year time period, to develop a robust estimate of the population genetic history of these diversifying lineages. Conclusion The conclusions from previous work are well supported by our comprehensive analysis. In particular, we find that the genetic diversity of derived crater lake populations is lower than that of the source population regardless of when and how each population was sampled. Furthermore, changes in various estimates of

  7. Extracellular biosynthesis of silver nanoparticles using Bacillus sp. GP-23 and evaluation of their antifungal activity towards Fusarium oxysporum

    Science.gov (United States)

    Gopinath, V.; Velusamy, P.

    2013-04-01

    In last few decades nanoparticles have attracted and emerged as a field in biomedical research due to their incredible applications. The current research was focused on extracellular synthesis of silver nanoparticles (AgNPs) using cell free culture supernatant of strain GP-23. It was found that the strain GP-23 belonged to Bacillus species by 16S rRNA sequence analysis. Biosynthesis of AgNPs was achieved by addition of culture supernatant with aqueous silver nitrate solution, after 24 h it turned to brown color solution with a peak at 420 nm corresponding to the Plasmon absorbance of AgNPs by UV-Vis Spectroscopy. The nanoparticles were characterized by FTIR, XRD, HRTEM, EDX and AFM. The synthesized nanoparticles were found to be spherical in shape with size in the range of 7-21 nm. It was stable in aqueous solution for five months period of storage at room temperature under dark condition. The biosynthesized AgNPs exhibited strong antifungal activity against plant pathogenic fungus, Fusarium oxysporum at the concentration of 8 μg ml-1. The results suggest that the synthesized AgNPs act as an effective antifungal agent/fungicide.

  8. Fusarium oxysporum mediates systems metabolic reprogramming of chickpea roots as revealed by a combination of proteomics and metabolomics.

    Science.gov (United States)

    Kumar, Yashwant; Zhang, Limin; Panigrahi, Priyabrata; Dholakia, Bhushan B; Dewangan, Veena; Chavan, Sachin G; Kunjir, Shrikant M; Wu, Xiangyu; Li, Ning; Rajmohanan, Pattuparambil R; Kadoo, Narendra Y; Giri, Ashok P; Tang, Huiru; Gupta, Vidya S

    2016-07-01

    Molecular changes elicited by plants in response to fungal attack and how this affects plant-pathogen interaction, including susceptibility or resistance, remain elusive. We studied the dynamics in root metabolism during compatible and incompatible interactions between chickpea and Fusarium oxysporum f. sp. ciceri (Foc), using quantitative label-free proteomics and NMR-based metabolomics. Results demonstrated differential expression of proteins and metabolites upon Foc inoculations in the resistant plants compared with the susceptible ones. Additionally, expression analysis of candidate genes supported the proteomic and metabolic variations in the chickpea roots upon Foc inoculation. In particular, we found that the resistant plants revealed significant increase in the carbon and nitrogen metabolism; generation of reactive oxygen species (ROS), lignification and phytoalexins. The levels of some of the pathogenesis-related proteins were significantly higher upon Foc inoculation in the resistant plant. Interestingly, results also exhibited the crucial role of altered Yang cycle, which contributed in different methylation reactions and unfolded protein response in the chickpea roots against Foc. Overall, the observed modulations in the metabolic flux as outcome of several orchestrated molecular events are determinant of plant's role in chickpea-Foc interactions. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  9. Isolation of vanilla-endophytic bacteria (Vanilla planifolia with in vitro biocontrol activity against Fusarium oxysporum f. sp. Vanillae

    Directory of Open Access Journals (Sweden)

    Karol Jiménez-Quesada

    2015-06-01

    Full Text Available Vanilla sp. genus belongs to Orchidaceae family, and V. planifolia, V. pompona and V. tahitensis. are species of commercial interest. The quality classification of vanilla is made according to the length of the capsule and vanillin content, which is used to make food and beverage, as raw material in the pharmaceutical industry and for the production of cosmetics and perfumes, among others. Currently, root rot caused by the fungus Fusarium oxyporum f. sp. Vanillae is considered to be the biggest problem facing vanilla production, causing 30 to 52% of plant death, attacking adventitious roots and preventing this plant is able to absorb water and nutrients. The fungus cannot be eradicated by the action of chemicals that damage the viability of the plants, and because the cultivation of vanilla in agroforestry systems without the application of agrochemicals is an activity that is gaining interest among small producers country. It is for this reason why was studied the ability of control of vanilla endophytic bacteria isolated from samples from Corcovado, Puriscal, Dota and Guápiles, by testing in vitro antagonism between asylee bacteria and fungus F. oxysporum, giving results about promising candidate B1M11 to respond to pathogen attack, which was corroborated by the appearance of a halo of inhibition of fungal growth on plate.

  10. Phylogenetic relationships among members of the Fusarium solani species complex in human infections and the descriptions of F. keratoplasticum sp. nov. and F. petroliphilum stat. nov

    DEFF Research Database (Denmark)

    Short, Dylan P.G.; O’Donnell, Kerry; Thrane, Ulf

    2013-01-01

    Fusarium species are frequently associated with mycotic keratitis and, to a lesser extent, cases of localized and disseminated infections. The Fusarium solani species complex (FSSC) is the most common group of fusaria associated with human infectious diseases. Several studies to date have revealed...... dozens of strongly supported phylogenetic species within this important evolutionary clade, though little work has been done to improve the taxonomy and understanding of the reproductive mode and phenotypes of the predominant cl