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Sample records for pelletized biocontrol fungi

  1. Method To Enhance Growth and Sporulation of Pelletized Biocontrol Fungi

    PubMed Central

    Knudsen, G. R.; Eschen, D. J.; Dandurand, L. M.; Wang, Z. G.

    1991-01-01

    The biocontrol fungi Trichoderma harzianum, used to control soilborne plant pathogens, and Beauveria bassiana, used to control insect pests, were formulated as mycelial biomass in alginate pellets with wheat bran added. After drying for 0, 4, or 16 h, pellets were placed in water or in aqueous solutions of polyethylene glycol (PEG) 8000 for 4 to 24 h and then allowed to continue drying. PEG-treated pellets containing T. harzianum showed significantly greater proliferation of hyphae in soil than untreated pellets or pellets treated with water. Production of conidia of T. harzianum from PEG-treated pellets was lower than production from untreated pellets after 4 days, although rates were equivalent after 7 days. In contrast, production of conidia of B. bassiana was significantly more rapid from PEG-treated pellets than from untreated pellets. Biocontrol of soilborne plant pathogens or insect pests may be enhanced by rapid hyphal growth of T. harzianum in soil or rapid sporulation of B. bassiana on foliage, respectively. Therefore, PEG treatment may improve the efficacy of these biocontrol agents. PMID:16348562

  2. Effect of seed pelleting with biocontrol agents on growth and colonisation of roots of mungbean by root-infecting fungi.

    PubMed

    Ramzan, Nadia; Noreen, Nayara; Perveen, Zahida; Shahzad, Saleem

    2016-08-01

    Mungbean (Vigna radiata (L.) Wilczek) is a leguminous pulse crop that is a major source of proteins, vitamins and minerals. Root-infecting fungi produce severe plant diseases like root rot, charcoal rot, damping-off and stem rot. The soil-borne pathogens can be controlled by chemicals, but these chemicals have several negative effects. Use of microbial antagonist such as fungi and bacteria is a safe, effective and eco-friendly method for the control of many soil-borne pathogens. Biological control agents promote plant growth and develop disease resistance. Application of bacteria and fungi as seed dressing suppressed the root-infecting fungi on leguminous crops. Seeds of mungbean were pelleted with different biocontrol agents to determine their effect on plant growth and colonisation of roots by root-infecting fungi, viz. Fusarium solani, Macrophomina phaseolina, Pythium aphanidermatum, Rhizoctonia solani and Sclerotium rolfsii. Treatment of mungbean seeds with fungal antagonists showed more shoot and root length as compared to bacterial antagonists, whereas seed treated with bacterial antagonists showed maximum shoot and root weight. Trichoderma harzianum and Bacillus subtilis were the best among all the biocontrol agents since they provided the highest plant growth and greater reduction in root colonisation by all root-infecting fungi. Bacillus cereus, Trichoderma virens, Pseudomonas fluorescens and Micrococcus varians were also effective against root-infecting fungi but to a lesser extent. T. harzianum, T. virens, B. subtilis and P. fluorescens were found to be best among all biocontrol agents. The root-infecting fungi can be controlled by pelleting seeds with biocontrol agents as it is safe and effective method. Additionally, plant growth was promoted more by this method. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  3. Biocontrol: Fungi as Nematode Control Agents

    PubMed Central

    Mankau, R.

    1980-01-01

    The fungal antagonists of nematodes consist of a great variety of organisms belonging to widely divergent orders and families of fungi. They include the nematode-trapping fungi, endoparasitic fungi, parasites of nematode eggs and cysts, and fungi which produce metabolites toxic to nematodes. The diversity, adaptations, and distribution of nematode-destroying fungi and taxonomic problems encountered in their study are reviewed. The importance of nemato-phagous fungi in soil biology, with special emphasis on their relationship to populations of plant-parasitic nematodes, is considered. While predacious fungi have long been investigated as possible biocontrol agents and have often exhibited spectacular results in vitro, their performance in field studies has generated little enthusiasm among nematologists. To date no species has demonstrated control of any plant pest to a degree achieved with nematicides, but recent studies have provided a much clearer concept of possibilities and problems in the applied use of fungal antagonists. The discovery of new species, which appear to control certain pests effectively under specific conditions, holds out some promise that fungi may be utilized as alternatives to chemical control after a more thorough and expanded study of their biology and ecology. PMID:19300699

  4. Evaluation of recycled bioplastic pellets and a sprayable formulation for application of an Aspergillus flavus biocontrol strain

    USDA-ARS?s Scientific Manuscript database

    Biocontrol of Aspergillus flavus using inoculated bioplastic granules has been proven to be effective under laboratory and field conditions. In the present study, the use of low-density pellets from recycled bioplastic as a biocontrol strain carrier was evaluated. Applying recycled bioplastic pell...

  5. Insight into tick biocontrol with special regard to fungi.

    PubMed

    Lonc, Elżbieta; Guz-Regner, Katarzyna; Kiewra, Dorota; Szczepańska, Anna

    2014-01-01

    The epidemiological and epizootic importance of ticks has been known for a few decades since of the discovery of their role as vectors of many new diseases, and the better detection of those already known. Given the durability of chemical preparations in the environment and the increasing problem of developing tick resistance, natural strategies for biological control are sought. A promising alternative to chemical pesticides is the use of entomopathogenic organisms for effective integrated pest management of low environmental impact. A number of promising microbes have been identified during the search for effective means of controlling the tick population, but the knowledge about the impact of these pathogens on the environment and other non-target organisms is still insufficient. Previous research has still not provided a definite answer about the safety of their use. It is known, however,that the chemicals which are currently used have a negative impact on the environment and/or cause resistance. No efficient biocompound has yet been devised for commercial use. Potential microorganisms for tick biocontrol (mainly bacteria and fungi) are natural tick pathogens, living in the same environment. With their adhesive properties, and their ability to digest the cuticle, they may constitute an appropriate ingredient of bioacaricides. Until now, fungal insecticides have been used only to control crop pests.

  6. Phylogeny of certain biocontrol agents with special reference to nematophagous fungi based on RAPd.

    PubMed

    Jarullah, B M S; Subramanian, R B; Jummanah, M S J

    2005-01-01

    A number of phylogenetic studies have been carried out on biocontrol agents having similar biological control activity. However, no work has been carried out to determine the phylogenetic relationship amongst various groups of biological control agents with varied biocontrol properties. Our aim was to derive a phylogenetic relationship between diverse biocontrol agents belonging to the deuteromycetes and determine its correlation with their spore morphology and their biocontrol activity. RAPD was used to assess genomic variability in fungi used as biological control agents which included ten isolates of nematophagous fungi such as Arthrobotrys sp., Duddingtonia sp., Paecilomyces sp. and Verticillium sp., along with two isolates of fungal biocontrol agents such as Trichoderma sp. and two isolates of entomopathogenic fungi including Beauveria sp. A plant pathogenic fungus, Verticillium alboatrum was also included to increase the diversity of Deuteromycetes used. A similarity matrix was created using Jaccard's similarity coefficient & clustering was done using unweighted pair group arithmetic mean method (UPGMA). The final dendogram was created using a combination of two programs, Freetree and TreeExplorer. The phylogenetic tree constructed from the RAPD data showed marked genetic variability among different strains of the same species. The spore morphologies of all these fungi were also studied. The phylogenetic pattern could be correlated with the conidial and conidiophore morphology, a criterion commonly used for the classification of fungi in general and Deuteromycetes in particular. Interestingly, the inferred phylogeny showed no significant grouping based on either their biological control properties or the trapping structures amongst the nematophagous fungi as reported earlier by other workers. The phylogenetic pattern was also similar to the tree obtained by comparing the 18S rRNA sequences from the database. The result clearly indicates that the classical

  7. Human exposure to airborne fungi from genera used as biocontrol agents in plant production.

    PubMed

    Madsen, Anne Mette; Hansen, Vinni Mona; Meyling, Nicolai Vitt; Eilenberg, Jørgen

    2007-01-01

    The fungi Trichoderma harzianum, T. polysporum, T. viride, Paeciliomyces fumosoroseus, P. lilacinus, Verticillium/lecanicillium lecanii, Ulocladium oudemansii, U. atrum and Beauveria bassiana are used or considered to be used for biocontrol of pests and plant diseases. Human exposure to these fungi in environments where they may naturally occur or are used as biocontrol agents has not been directly investigated to date. This review aims to provide an overview of the current knowledge of human exposure to fungi from the relevant genera. The subject of fungal taxonomy due to the rapid development of this issue is also discussed. B. bassiana, V. lecanii, T. harzianum, T. polysporum, P. lilacinus and U. oudemansii were infrequently present in the air and thus people in general seem to be seldom exposed to these fungi. However, when V. lecanii was present, high concentrations were measured. Fungi from the genera Trichoderma, Paecilomyces and Ulocladium were rarely identified to the species level and sometimes high concentrations were reported. T. viride and U. atrum were detected frequently in different environments and sometimes with a high frequency of presence in samples. Thus, people seem to be frequently exposed to these fungi. Sequence data have led to recent revisions of fungal taxonomy, and in future studies it is important to specify the taxonomy used for identification, thus making comparisons possible.

  8. Managing the plant microbiome for biocontrol fungi: examples from Hypocreales.

    PubMed

    Kepler, Ryan M; Maul, Jude E; Rehner, Stephen A

    2017-04-22

    Feeding an increasing global population requires continued improvements in agricultural efficiency and productivity. Meeting estimated future production levels requires the adoption of practices that increase output without environmental degradation associated with external inputs to supplement nutrition or control pests. Enriching the community of microbes associated with plants in agricultural systems for those providing ecosystem services such as pest control is one possible component towards achieving sustainable productivity increases. In this review we explore the current state of knowledge for Hypocreales fungi used in biological control. Advances in understanding the field ecology, diversity and genetic determinants of host range and virulence of hypocrealean fungi provide the means to improve their efficacy. Published by Elsevier Ltd.

  9. [Antagonistic interactions between saprotrophic fungi and geohelminths. 2. Saprotrophic fungi in biocontrol of parasitic geohelminths of humans and animals].

    PubMed

    Jaborowska-Jarmoluk, Magdalena; Mazurkiewicz-Zapałowicz, Kinga; Kołodziejczyk, Lidia

    2009-01-01

    The soils ecosystem plays an important role in the epidemiology of geohelminth diseases of humans and animals. Soil contamination with ova of the parasitic geohelminths represents a global public health-hazard issue. Biological agents have been thought to control the infective forms of parasites present in the soil. Biocontrol of geohelminths represents an alternative to pesticides (i.e., nematicides), which are not efficient in killing infective nematode forms and, additionally, result in the environment pollution and long-term disturbances in the soil ecosystem homeostasis. The degree of the inhibiting effect of soil saprotrophic fungi on geohelminth embryonic development varies and depends on the species. A number of fungi cause various morphological disorders in the embryos of developing parasitic nematodes, but also have an ovicidal effect. Although the nature of the antagonism between fungi and other living organisms has not been fully explained, it is certain that mycotoxins and fungal enzymes constitute its important components. Considering the studies carried out so far, the antagonistic effect of mold fungi against the infective stages of geohelminths can be fully recommended as a real control factor, especially as these saprotrophs represent a natural factor within the soil environment, that is of particular biochemical activity.

  10. Endophytic fungi associated with Monarda citriodora, an aromatic and medicinal plant and their biocontrol potential.

    PubMed

    Katoch, Meenu; Pull, Shipra

    2017-12-01

    The Food and Agriculture Organization has estimated that every year considerable losses of the food crops occur due to plant diseases. Although fungicides are extensively used for management of plant diseases, they are expensive and hazardous to the environment and human health. Alternatively, biological control is the safe way to overcome the effects of plant diseases and to sustain agriculture. Since Monarda citriodora Cerv. ex Lag. (Lamiaceae/Labiatae) is known for its antifungal properties, it was chosen for the study. The isolation of endophytic fungi from M. citriodora and assessing their biocontrol potential. The isolated endophytes were characterized using ITS-5.8 S rDNA sequencing. Their biocontrol potential was assessed using different antagonistic assays against major plant pathogens. Twenty-eight endophytes representing 11 genera were isolated, of which, around 82% endophytes showed biocontrol potential against plant pathogens. MC-2 L (Fusarium oxysporum), MC-14 F (F. oxysporum), MC-22 F (F. oxysporum) and MC-25 F (F. redolens) displayed significant antagonistic activity against all the tested pathogens. Interestingly, MC-10 L (Muscodor yucatanensis) completely inhibited the growth of Sclerotinia sp., Colletotrichum capsici, Aspergillus flavus and A. fumigatus in dual culture assay, whereas MC-8 L (A. oryzae) and MC-9 L (Penicillium commune) completely inhibited the growth of the Sclerotinia sp. in fumigation assay. Endophytes MC-2 L, MC-14 F, MC-22 F and MC-25 F could effectively be used to control broad range of phytopathogens, while MC-10 L, MC-8 L and MC-9 L could be used to control specific pathogens. Secondly, endophytes showing varying degrees of antagonism in different assays represented the chemo-diversity not only as promising biocontrol agents but also as a resource of defensive and bioactive metabolites.

  11. Lactic acid bacteria from fresh fruit and vegetables as biocontrol agents of phytopathogenic bacteria and fungi.

    PubMed

    Trias, Rosalia; Bañeras, Lluís; Montesinos, Emilio; Badosa, Esther

    2008-12-01

    This study evaluated the efficacy of lactic acid bacteria (LAB) isolated from fresh fruits and vegetables as biocontrol agents against the phytopathogenic and spoilage bacteria and fungi, Xanthomonas campestris, Erwinia carotovora, Penicillium expansum, Monilinia laxa, and Botrytis cinerea. The antagonistic activity of 496 LAB strains was tested in vitro and all tested microorganisms except P. expansum were inhibited by at least one isolate. The 496 isolates were also analyzed for the inhibition of P. expansum infection in wounds of Golden Delicious apples. Four strains (TC97, AC318, TM319, and FF441) reduced the fungal rot diameter of the apples by 20%; only Weissella cibaria strain TM128 decreased infection levels by 50%. Cell-free supernatants of selected antagonistic bacteria were studied to determine the nature of the antimicrobial compounds produced. Organic acids were the preferred mediators of inhibition but hydrogen peroxide was also detected when strains BC48, TM128, PM141 and FF441 were tested against E. carotovora. While previous reports of antifungal activity by LAB are scarce, our results support the potential of LAB as biocontrol agents against postharvest rot.

  12. Combinations of Biocontrol Agents for Management of Plant-Parasitic Nematodes and Soilborne Plant-Pathogenic Fungi

    PubMed Central

    Meyer, Susan L. F.; Roberts, Daniel P.

    2002-01-01

    Numerous microbes are antagonistic to plant-parasitic nematodes and soilborne plant-pathogenic fungi, but few of these organisms are commercially available for management of these pathogens. Inconsistent performance of applied biocontrol agents has proven to be a primary obstacle to the development of successful commercial products. One of the strategies for overcoming inconsistent performance is to combine the disease-suppressive activity of two (or more) beneficial microbes in a biocontrol preparation. Such combinations have potential for more extensive colonization of the rhizosphere, more consistent expression of beneficial traits under a broad range of soil conditions, and antagonism to a larger number of plant pests or pathogens than strains applied individually. Conversely, microbes applied in combination also may have antagonistic interactions with each other. Increased, decreased, and unaltered suppression of the target pathogen or pest has been observed when biocontrol microbes have been applied in combination. Unfortunately, the ecological basis for increased or decreased suppression has not been determined in many cases and needs further consideration. The complexity of interactions involved in the application of multiple organisms for biological control has slowed progress toward development of successful formulations. However, this approach has potential for overcoming some of the efficacy problems that occur with application of individual biocontrol agents. PMID:19265899

  13. Arbuscular Mycorrhizal Fungi for the Biocontrol of Plant-Parasitic Nematodes: A Review of the Mechanisms Involved.

    PubMed

    Schouteden, Nele; De Waele, Dirk; Panis, Bart; Vos, Christine M

    2015-01-01

    Arbuscular mycorrhizal fungi (AMF) are obligate root symbionts that can protect their host plant against biotic stress factors such as plant-parasitic nematode (PPN) infection. PPN consist of a wide range of species with different life styles that can cause major damage in many important crops worldwide. Various mechanisms have been proposed to play a role in the biocontrol effect of AMF against PPN. This review presents an overview of the different mechanisms that have been proposed, and discusses into more detail the plausibility of their involvement in the biocontrol against PPN specifically. The proposed mechanisms include enhanced plant tolerance, direct competition for nutrients and space, induced systemic resistance (ISR) and altered rhizosphere interactions. Recent studies have emphasized the importance of ISR in biocontrol and are increasingly placing rhizosphere effects on the foreground as well, both of which will be the focal point of this review. Though AMF are not yet widely used in conventional agriculture, recent data help to develop a better insight into the modes of action, which will eventually lead toward future field applications of AMF against PPN. The scientific community has entered an exciting era that provides the tools to actually unravel the underlying molecular mechanisms, making this a timely opportunity for a review of our current knowledge and the challenges ahead.

  14. Arbuscular Mycorrhizal Fungi for the Biocontrol of Plant-Parasitic Nematodes: A Review of the Mechanisms Involved

    PubMed Central

    Schouteden, Nele; De Waele, Dirk; Panis, Bart; Vos, Christine M.

    2015-01-01

    Arbuscular mycorrhizal fungi (AMF) are obligate root symbionts that can protect their host plant against biotic stress factors such as plant-parasitic nematode (PPN) infection. PPN consist of a wide range of species with different life styles that can cause major damage in many important crops worldwide. Various mechanisms have been proposed to play a role in the biocontrol effect of AMF against PPN. This review presents an overview of the different mechanisms that have been proposed, and discusses into more detail the plausibility of their involvement in the biocontrol against PPN specifically. The proposed mechanisms include enhanced plant tolerance, direct competition for nutrients and space, induced systemic resistance (ISR) and altered rhizosphere interactions. Recent studies have emphasized the importance of ISR in biocontrol and are increasingly placing rhizosphere effects on the foreground as well, both of which will be the focal point of this review. Though AMF are not yet widely used in conventional agriculture, recent data help to develop a better insight into the modes of action, which will eventually lead toward future field applications of AMF against PPN. The scientific community has entered an exciting era that provides the tools to actually unravel the underlying molecular mechanisms, making this a timely opportunity for a review of our current knowledge and the challenges ahead. PMID:26635750

  15. Antifungal modes of action of Saccharomyces and other biocontrol yeasts against fungi isolated from sour and grey rots.

    PubMed

    Nally, M C; Pesce, V M; Maturano, Y P; Rodriguez Assaf, L A; Toro, M E; Castellanos de Figueroa, L I; Vazquez, F

    2015-07-02

    The aim of this study was to determine the putative modes of action of 59 viticultural yeasts (31 Saccharomyces and 28 non-Saccharomyces) that inhibited fungi isolated from sour and grey rot in grapes. Inhibition of fungal mycelial growth by metabolites, enzyme activities (laminarinases, chitinases), antifungal volatiles, competition for nutrients (siderophores, Niche Overlap Index (NOI)), inhibition of fungal spore germination and decreased germinal tube length and induction of resistance were assayed. Biofungicide yeasts were classified into "antifungal patterns", according to their mechanisms of action. Thirty isolates presented at least two of the mechanisms assayed. We propose that inhibition of fungal mycelial growth by metabolites, laminarinases, competition for nutrients, inhibition of fungal spore germination and decreased germinal tube length, and antifungal volatiles by Saccharomyces and non-Saccharomyces viticultural yeasts is used as putative biocontrol mechanisms against phytopathogenic fungi. Twenty-four different antifungal patterns were identified. Siderophore production (N)and a combination of siderophore production and NOI>0.92 (M)were the most frequent antifungal patterns observed in the biofungicide yeasts assayed. Elucidation of these mechanisms could be useful for optimization of an inoculum formulation, resulting in a more consistent control of grey and sour rot with Saccharomyces and non-Saccharomyces biocontrol yeasts.

  16. Effects of carbon concentration and carbon to nitrogen ratio on the growth and sporulation of several biocontrol fungi.

    PubMed

    Gao, Li; Sun, Man H; Liu, Xing Z; Che, Yong S

    2007-01-01

    Effects of carbon concentration and carbon to nitrogen (C:N) ratio on six biocontrol fungal strains are reported in this paper. All fungal strains had extensive growth on the media supplemented with 6-12 gl(-1) carbon and C:N ratios from 10:1 to 80:1, and differed in nutrient requirements for sporulation. Except for the two strains of Paecilomyces lilacinus, all selected fungi attained the highest spore yields at a C:N ratio of 160:1 when the carbon concentration was 12 gl(-1) for Metarhizium anisopliae SQZ-1-21, 6 gl(-1) for M. anisopliae RS-4-1 and Trichoderma viride TV-1, and 8 gl(-1) for Lecanicillium lecanii CA-1-G. The optimal conditions for P. lilacinus sporulation were 8 gl(-1) carbon with a C:N ratio of 10:1 for M-14 and 12 gl(-1) carbon with a C:N ratio of 20:1 for IPC-P, respectively. The results indicated that the influence of carbon concentration and C:N ratio on fungal growth and sporulation is strain dependent; therefore, consideration for the complexity of nutrient requirements is essential for improving yields of fungal biocontrol agents.

  17. [Application of Bacillus-antagonists for biocontrol of fungi degrading raw wood].

    PubMed

    Melent'ev, A I; Helisto, P; Kuz'mina, L Iu; Galimzianova, N F; Aktuganov, G E; Korpela, T

    2006-01-01

    Species composition of micromycete complexes colonizing aspen, birch, and pine wood was studied. Calculation of the Sorens-Tchekanovsky similarity coefficients showed that these complexes shared a high degree of similarity. They were dominated by the representatives of the genera Penicillium, Paecilomyces, Trichoderma, and Rhizopus. Some antagonistic bacilli inhibited growth and development of wood-decay fungi in vitro and led to the formation of spheroplasts on growing hyphae. A study of possible involvement of bacillary mycolytic enzymes in the inhibition of wood-decay fungi demonstrated selectivity of their lytic effect, which was determined by the genus and species of micromycetes and did not correlate with their relative resistance to antagonists.

  18. Production of trichodiene by Trichoderma harzianum alters the perception of this biocontrol strain by plants and antagonized fungi.

    PubMed

    Malmierca, Mónica G; McCormick, Susan P; Cardoza, Rosa E; Alexander, Nancy J; Monte, Enrique; Gutiérrez, Santiago

    2015-08-01

    Trichothecenes are phytotoxic sesquiterpenic mycotoxins that can act as virulence factors in plant diseases. Harzianum A (HA) is a non-phytotoxic trichothecene produced by Trichoderma arundinaceum. The first step in HA biosynthesis is the conversion of farnesyl diphosphate to trichodiene (TD), a volatile organic compound (VOC), catalysed by a sesquiterpene synthase encoded by the tri5 gene. Expression of tri5 in the biocontrol strain Trichoderma harzianum CECT 2413 resulted in production of TD in parallel with a reduction of ergosterol biosynthesis and an unexpected increase in the level of squalene. Transformants expressing tri5 displayed low chitinase activity and induced expression of Botrytis cinerea BOT genes, although their total antagonistic potential against phytopathogenic fungi was not reduced. VOCs released by the tri5-transformant induced expression of tomato defence genes related to salicylic acid (SA), and TD itself strongly induced the expression of SA-responsive genes and reduced the development of lateral roots. Together, these results suggest that TD acts as a signalling VOC in the interactions of Trichoderma with plants and other microorganisms by modulating the perception of this fungus to a given environment. Moreover, the TD ability to induce systemic defences indicates that complex trichothecene structures may not be necessary for inducing such responses.

  19. Biocontrol Activity of Bacillus subtilis Isolated from Agaricus bisporus Mushroom Compost Against Pathogenic Fungi.

    PubMed

    Liu, Can; Sheng, Jiping; Chen, Lin; Zheng, Yanyan; Lee, David Yue Wei; Yang, Yang; Xu, Mingshuang; Shen, Lin

    2015-07-08

    Bacillus subtilis strain B154, isolated from Agaricus bisporus mushroom compost infected by red bread mold, exhibited antagonistic activities against Neurospora sitophila. Antifungal activity against phytopathogenic fungi was also observed. The maximum antifungal activity was reached during the stationary phase. This antifungal activity was stable over a wide pH and temperature range and was not affected by proteases. Assay of antifungal activity in vitro indicated that a purified antifungal substance could strongly inhibit mycelia growth and spore germination of N. sitophila. In addition, treatment with strain B154 in A. bisporus mushroom compost infected with N. sitophila significantly increased the yield of bisporus mushrooms. Ultraviolet scan spectroscopy, tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis, matrix-associated laser desorption ionization time-of-flight mass spectrometry, and electrospray ionization tandem mass spectrometry analyses revealed a molecular weight consistent with 1498.7633 Da. The antifungal compound might belong to a new type of lipopeptide fengycin.

  20. Impact of Biocontrol Pseudomonas fluorescens CHA0 and a Genetically Modified Derivative on the Diversity of Culturable Fungi in the Cucumber Rhizosphere

    PubMed Central

    Girlanda, M.; Perotto, S.; Moenne-Loccoz, Y.; Bergero, R.; Lazzari, A.; Defago, G.; Bonfante, P.; Luppi, A. M.

    2001-01-01

    Little is known about the effects of Pseudomonas biocontrol inoculants on nontarget rhizosphere fungi. This issue was addressed using the biocontrol agent Pseudomonas fluorescens CHA0-Rif, which produces the antimicrobial polyketides 2,4-diacetylphloroglucinol (Phl) and pyoluteorin (Plt) and protects cucumber from several fungal pathogens, including Pythium spp., as well as the genetically modified derivative CHA0-Rif(pME3424). Strain CHA0-Rif(pME3424) overproduces Phl and Plt and displays improved biocontrol efficacy compared with CHA0-Rif. Cucumber was grown repeatedly in the same soil, which was left uninoculated, was inoculated with CHA0-Rif or CHA0-Rif(pME3424), or was treated with the fungicide metalaxyl (Ridomil). Treatments were applied to soil at the start of each 32-day-long cucumber growth cycle, and their effects on the diversity of the rhizosphere populations of culturable fungi were assessed at the end of the first and fifth cycles. Over 11,000 colonies were studied and assigned to 105 fungal species (plus several sterile morphotypes). The most frequently isolated fungal species (mainly belonging to the genera Paecilomyces, Phialocephala, Fusarium, Gliocladium, Penicillium, Mortierella, Verticillium, Trichoderma, Staphylotrichum, Coniothyrium, Cylindrocarpon, Myrothecium, and Monocillium) were common in the four treatments, and no fungal species was totally suppressed or found exclusively following one particular treatment. However, in each of the two growth cycles studied, significant differences were found between treatments (e.g., between the control and the other treatments and/or between the two inoculation treatments) using discriminant analysis. Despite these differences in the composition and/or relative abundance of species in the fungal community, treatments had no effect on species diversity indices, and species abundance distributions fit the truncated lognormal function in most cases. In addition, the impact of treatments at the 32-day

  1. The double life of Ceratobasidium: orchid mycorrhizal fungi and their potential for biocontrol of Rhizoctonia solani sheath blight of rice.

    PubMed

    Mosquera-Espinosa, Ana Teresa; Bayman, Paul; Prado, Gustavo A; Gómez-Carabalí, Arnulfo; Otero, J Tupac

    2013-01-01

    Ceratobasidium includes orchid mycorrhizal symbionts, plant pathogens and biocontrol agents of soilborne plant pathogens. It is not known to what extent members of the first guild also can participate in the others. Ceratobasidium spp. were isolated from roots of Colombian orchids and identified by phylogeny based on nrITS sequences. Phylogenetic grouping of Ceratobasidium spp. isolates corresponded to orchid host substrate (epiphytic vs. terrestrial). Isolates were tested for virulence on rice and for biocontrol of Rhizoctonia solani, causal agent of sheath blight of rice. All Ceratobasidium spp. isolates caused some signs of sheath blight but significantly less than a pathogenic R. solani used as a positive control. When Ceratobasidium spp. isolates were inoculated on rice seedlings 3 d before R. solani, they significantly reduced disease expression compared to controls inoculated with R. solani alone. The use of Ceratobasidium spp. from orchids for biological control is novel, and biodiverse countries such as Colombia are promising places to look for new biocontrol agents.

  2. Coadministration of sodium alginate pellets containing the fungi Duddingtonia flagrans and Monacrosporium thaumasium on cyathostomin infective larvae after passing through the gastrointestinal tract of horses.

    PubMed

    Tavela, Alexandre de Oliveira; de Araújo, Jackson Victor; Braga, Fábio Ribeiro; da Silveira, Wendeo Ferreira; Dornelas e Silva, Vinicius Herold; Carretta Júnior, Moacir; Borges, Luana Alcântara; Araujo, Juliana Milani; Benjamin, Laércio dos Anjos; Carvalho, Giovanni Ribeiro; de Paula, Alessandra Teixeira

    2013-06-01

    The predatory nematophagous fungi have been used as an alternative control of gastrointestinal nematodes of domestic animals in natural and laboratory conditions. However, it is unclear if the association of some of these species could bring some kind of advantage, from a biological standpoint. In this context, this study consisted of two tests in vitro: in assay A, the assessment of the viability of the association of pellets in sodium alginate matrix containing the fungus Duddingtonia flagrans (AC001) and Monacrosporium thaumasium (NF34) and its predatory activity on infective larvae (L3) of cyathostomin after passing through the gastrointestinal tract of horses and assay B, assessment of the cyathostomin L3 reduction percentage in coprocultures. Twelve crossbred horses, females, with a mean weight of 356 kg and previously dewormed were divided in three groups with four animals each: group 1, each animal received 50 g of pellets containing mycelial mass of the fungus D. flagrans and 50 g of pellets of the fungus M. thaumasium, associated and in a single oral dose; group 2, 100 g of pellets containing D. flagrans and 100 g of pellets containing M. thaumasium, associated and in a single oral dose; group 3, control. Faecal samples were collected from animals in the treated and control groups at time intervals of 12, 24, 36, 48, 60 and 72 h after the administration of treatments and placed in Petri dishes containing 2% water-agar (assay A) and cups for coprocultures (assay B). Subsequently, 1000 cyathostomin L3 were added to each Petri dish (assay A) and 1000 cyathostomin eggs were added to each coproculture (assay B) of fungi-treated and control groups. At the end of 15 days, there was observed that the two associations of pellets containing the fungi tested showed predatory activity after passing through the gastrointestinal tract of horses (assay A). In assay B, all the intervals studied showed reduction rate in the number of L3 recovered from coprocultures

  3. Antibiotic Extraction as a Recent Biocontrol Method for Aspergillus Niger andAspergillus Flavus Fungi in Ancient Egyptian mural paintings

    NASA Astrophysics Data System (ADS)

    Hemdan, R. Elmitwalli; Fatma, Helmi M.; Rizk, Mohammed A.; Hagrassy, Abeer F.

    Biodeterioration of mural paintings by Aspergillus niger and Aspergillus flavus Fungi has been proved in different mural paintings in Egypt nowadays. Several researches have studied the effect of fungi on mural paintings, the mechanism of interaction and methods of control. But none of these researches gives us the solution without causing a side effect. In this paper, for the first time, a recent treatment by antibiotic "6 penthyl α pyrone phenol" was applied as a successful technique for elimination of Aspergillus niger and Aspergillus flavus. On the other hand, it is favorable for cleaning Surfaces of Murals executed by tembera technique from the fungi metabolism which caused a black pigments on surfaces.

  4. Potential for biocontrol of melanized fungi by actinobacteria isolated from intertidal region of Ilha Do Mel, Paraná, Brazil.

    PubMed

    Dalitz, Camila de Araújo; Porsani, Mariana Vieira; Figel, Izabel Cristina; Pimentel, Ida C; Dalzoto, Patrícia R

    Actinobacteria occur in many environments and have the capacity to produce secondary metabolites with antibiotic potential. Identification and taxonomy of actinobacteria that produce antimicrobial substances is essential for the screening of new compounds, and sequencing of the 16S region of ribosomal DNA (rDNA), which is conserved and present in all bacteria, is an important method of identification. Melanized fungi are free-living organisms, which can also be pathogens of clinical importance. This work aimed to evaluate growth inhibition of melanized fungi by actinobacteria and to identify the latter to the species level. In this study, antimicrobial activity of 13 actinobacterial isolates from the genus Streptomyces was evaluated against seven melanized fungi of the genera Exophiala, Cladosporium, and Rhinocladiella. In all tests, all actinobacterial isolates showed inhibitory activity against all isolates of melanized fungi, and only one actinobacterial isolate had less efficient inhibitory activity. The 16S rDNA region of five previously unidentified actinobacterial isolates from Ilha do Mel, Paraná, Brazil, was sequenced; four of the isolates were identified as Streptomyces globisporus subsp. globisporus, and one isolate was identified as Streptomyces aureus. This work highlights the potential of actinobacteria with antifungal activity and their role in the pursuit of novel antimicrobial substances. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  5. A novel method to harvest microalgae via co-culture of filamentous fungi to form cell pellets.

    PubMed

    Zhang, Jianguo; Hu, Bo

    2012-06-01

    While current approaches have limitations for efficient and cost-effective microalgal biofuel production, new processes, which are financially economic, environmentally sustainable, and ecologically stable, are needed. Typically, microalgae cells are small and grow individually. Harvest of these cells is technically difficult and it contributes to 20-30% of the total cost of biomass production. A new process of pelletized cell cultivation is described in this study to co-culture a filamentous fungal species with microalgae so that microalgae cells can be co-pelletized into fungal pellets for easier harvest. This new process can be applied to microalgae cultures in both autotrophic and heterotrophic conditions to allow microalgae cells attach to each other. The cell pellets, due to their large size, can be harvested through sieve, much easier than individual cells. This method has the potential to significantly decrease the processing cost for generating microagal biofuel or other products.

  6. Sporulation of several biocontrol fungi as affected by carbon and nitrogen sources in a two-stage cultivation system.

    PubMed

    Gao, Li; Liu, Xingzhong

    2010-12-01

    The development of fungal biopesticides requires the efficient production of large numbers spores or other propagules. The current study used published information concerning carbon concentrations and C:N ratios to evaluate the effects of carbon and nitrogen sources on sporulation of Paecilomyces lilacinus (IPC-P and M-14) and Metarhizium anisopliae (SQZ-1-21 and RS-4-1) in a two-stage cultivation system. For P. lilacinus IPCP, the optimal sporulation medium contained urea as the nitrogen source, dextrin as the carbon source at 1 g/L, a C:N ratio of 5:1, with ZnSO(4)·7H(2)O at 10 mg/L and CaCl(2) at 3 g/L. The optimal sporulation medium for P. lilacinus M-14 contained soy peptone as the nitrogen source and maltose as the carbon source at 2 g/L, a C:N ratio of 10:1, with ZnSO(4)·7H(2)O at 250 mg/L, CuSO(4)·5H(2)O at 10 mg/L, H(3)BO(4) at 5 mg/L, and Na(2)MoO(4)·2H(2)O at 5 mg/L. The optimum sporulation medium for M. anisopliae SQZ-1-21 contained urea as the nitrogen source, sucrose as the carbon source at 16 g/ L, a C:N ratio of 80:1, with ZnSO(4)·7H(2)O at 50 mg/L, CuSO(4)·5H(2)O at 50 mg/L, H(3)BO(4) at 5 mg/L, and MnSO(4)·H(2)O at 10 mg/L. The optimum sporulation medium for M. anisopliae RS-4-1 contained soy peptone as the nitrogen source, sucrose as the carbon source at 4 g/L, a C:N ratio of 5:1, with ZnSO(4)·7H(2)O at 50 mg/L and H(3)BO(4) at 50 mg/L. All sporulation media contained 17 g/L agar. While these results were empirically derived, they provide a first step toward low-cost mass production of these biocontrol agents.

  7. Fungi

    USDA-ARS?s Scientific Manuscript database

    Fungi are seldom encountered in the archaeological record of foodstuffs but there are exceptions, especially for yeast. Excavated vessels contained identifiable residues of fermented beverages. Ancient ovens allow inferences on leavened breads. Mesopotamian clay tablets contain references to truffle...

  8. Endophytic Trichoderma gamsii YIM PH30019: a promising biocontrol agent with hyperosmolar, mycoparasitism, and antagonistic activities of induced volatile organic compounds on root-rot pathogenic fungi of Panax notoginseng.

    PubMed

    Chen, Jin-Lian; Sun, Shi-Zhong; Miao, Cui-Ping; Wu, Kai; Chen, You-Wei; Xu, Li-Hua; Guan, Hui-Lin; Zhao, Li-Xing

    2016-10-01

    Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T. gamsii YIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations. The results indicated that T. gamsii YIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%. T. gamsii YIM PH30019 displayed antagonistic activities against the pathogenic fungi of P. notoginseng via production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity. T. gamsii YIM PH30019 was able to improve the seedlings' emergence and protect P. notoginseng plants from soil-borne disease in the continuous cropping field tests. The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.

  9. Entomopathogenic fungi as potential biocontrol agents of the ecto-parasitic mite, Varroa destructor, and their effect on the immune response of honey bees (Apis mellifera L.).

    PubMed

    Hamiduzzaman, Mollah Md; Sinia, Alice; Guzman-Novoa, Ernesto; Goodwin, Paul H

    2012-11-01

    Three isolates of each of the entomopathogenic fungi, Metarhizium anisopliae, Beauveria bassiana and Clonostachys rosea, were assessed for their pathogenicity to the honey bee parasitic mite, Varroa destructor. The fungi were applied to varroa mites by immersing them in a spore solution, and then the inoculated mites were placed on honey bee brood inside capped cells. At 7 days post inoculation (dpi), the three fungi caused significant varroa mortality compared to non-inoculated mites. In brood treated only with varroa mites, expression of the honey bee genes, hymenoptaecin and poly U binding factor 68 Kd (pUf68), decreased over time, while expression of blue cheese (BlCh) and single minded (SiMd) was not affected. In brood inoculated directly only with M. anisopliae or B. bassiana, the emerged adults showed reduced weight indicating infection by the fungi, which was confirmed by observation of hyphae in the brood. Fungal infection of the brood resulted in increased expression of hymenoptaecin, pUf68 and BlCh, but not SiMd. In brood treated with varroa mites that had been inoculated with the fungi, expression of hymenoptaecin, pUf68 and BlCh, but not SiMd, was even more up-regulated. While varroa mites can suppress gene expression in honey bee brood, varroa mites infected with entomopathogenic fungi induced their expression. This may be due to a low level of fungal infection of the bee, which negated the immunosuppression by the mites. Therefore, entomopathogenic fungi could reduce varroa mite damage to honey bee brood by both infecting the parasite and preventing varroa-associated suppression of honey bee immunity. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Owl Pellets.

    ERIC Educational Resources Information Center

    Thompson, Craig D.

    1987-01-01

    Provides complete Project WILD lesson plans for 20-45-minute experiential science learning activity for grades 3-7 students. Describes how students construct a simple food chain through examination of owl pellets. Includes lesson objective, method, background information, materials, procedure, evaluation, and sources of owl pellets and posters.…

  11. Owl Pellets.

    ERIC Educational Resources Information Center

    Thompson, Craig D.

    1987-01-01

    Provides complete Project WILD lesson plans for 20-45-minute experiential science learning activity for grades 3-7 students. Describes how students construct a simple food chain through examination of owl pellets. Includes lesson objective, method, background information, materials, procedure, evaluation, and sources of owl pellets and posters.…

  12. Pelletizing lignite

    DOEpatents

    Goksel, Mehmet A.

    1983-11-01

    Lignite is formed into high strength pellets having a calorific value of at least 9,500 Btu/lb by blending a sufficient amount of an aqueous base bituminous emulsion with finely-divided raw lignite containing its inherent moisture to form a moistened green mixture containing at least 3 weight % of the bituminous material, based on the total dry weight of the solids, pelletizing the green mixture into discrete green pellets of a predetermined average diameter and drying the green pellets to a predetermined moisture content, preferrably no less than about 5 weight %. Lignite char and mixture of raw lignite and lignite char can be formed into high strength pellets in the same general manner.

  13. Statistical analysis and modeling of pelletized cultivation of Mucor circinelloides for microbial lipid accumulation.

    PubMed

    Xia, Chunjie; Wei, Wei; Hu, Bo

    2014-04-01

    Microbial oil accumulation via oleaginous fungi has some potential benefits because filamentous fungi can form pellets during cell growth and these pellets are easier to harvest from the culture broth than individual cells. This research studied the effect of various culture conditions on the pelletized cell growth of Mucor circinelloides and its lipid accumulation. The results showed that cell pelletization was positively correlated to biomass accumulation; however, pellet size was negatively correlated to the oil content of the fungal biomass, possibly due to the mass transfer barriers generated by the pellet structure. How to control the size of the pellet is the key to the success of the pelletized microbial oil accumulation process.

  14. Pellet Puzzlers.

    ERIC Educational Resources Information Center

    Hoots, R. A.

    1992-01-01

    Presents information on owl's taxonomy, characteristics, and influences on man. Describes owl pellets, which are digestive discards, and explains how they can be used to determine the owl's diet as a science activity. (PR)

  15. Pellet Puzzlers.

    ERIC Educational Resources Information Center

    Hoots, R. A.

    1992-01-01

    Presents information on owl's taxonomy, characteristics, and influences on man. Describes owl pellets, which are digestive discards, and explains how they can be used to determine the owl's diet as a science activity. (PR)

  16. Recombinant exochitinase of the thermophilic mould Myceliopthora thermophila BJA: Characteristics and utility in generating N-acetyl glucosamine and in biocontrol of phytopathogenic fungi.

    PubMed

    Dua, Ashima; Joshi, Swati; Satyanarayana, T

    2017-01-01

    Chitinase from the thermophilic mould Myceliopthora thermophila BJA (MtChit) is an acid tolerant, thermostable and organic solvent stable biocatalyst which does not require any metal ions for its activity. To produce high enzyme titres, reduce fermentation time and overcome the need for induction, this enzyme has been heterologously expressed under GAP promoter in the GRAS yeast, Pichia pastoris. The production medium supplemented with the permeabilizing agent Tween-20 supported two-fold higher rMtChit production (5.5 × 10(3) U L(-1) ). The consensus sequences S(132)xG(133)G(134) and D(168)xxD(171)xD(173)xE(175) in the enzyme have been found to represent the substrate binding and catalytic sites, respectively. The rMtChit, purified to homogeneity by a two-step purification strategy, is a monomeric glycoprotein of ∼48 kDa, which is optimally active at 55°C and pH 5.0. The enzyme is thermostable with t1/2 values of 113 and 48 min at 65 and 75°C, respectively. Kinetic parameters Km , Vmax , kcat , and kcat /Km of the enzyme are 4.655 mg mL(-1) , 34.246 nmol mg(-1)  s(-1) , 3.425 × 10(6) min(-1) , and 1.36 × 10(-6) mg mL(-1)  min(-1) , respectively. rMtChit is an unique exochitinase, since its action on chitin liberates N-acetylglucosamine NAG. The enzyme inhibits the growth of phytopathogenic fungi like Fusarium oxysporum and Curvularia lunata, therefore, this finds application as biofungicide at high temperatures during summer in tropics. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:70-80, 2017.

  17. Pelletized biochar as a carrier for AM fungi in the on-farm system of inoculum production in compost and vermiculite mixtures

    USDA-ARS?s Scientific Manuscript database

    On farm production of arbuscular mycorrhizal [AM] fungi is suitable for vegetable and horticultural crop production because the inocula may be efficiently mixed into horticultural potting media for plant production in the greenhouse. These inocula are not amenable for use in row crop production bec...

  18. Molecular Characterization and Identification of Biocontrol Isolates of Trichoderma spp.

    PubMed Central

    Hermosa, M. R.; Grondona, I.; Iturriaga, E. A.; Diaz-Minguez, J. M.; Castro, C.; Monte, E.; Garcia-Acha, I.

    2000-01-01

    The most common biological control agents (BCAs) of the genus Trichoderma have been reported to be strains of Trichoderma virens, T. harzianum, and T. viride. Since Trichoderma BCAs use different mechanisms of biocontrol, it is very important to explore the synergistic effects expressed by different genotypes for their practical use in agriculture. Characterization of 16 biocontrol strains, previously identified as “Trichoderma harzianum” Rifai and one biocontrol strain recognized as T. viride, was carried out using several molecular techniques. A certain degree of polymorphism was detected in hybridizations using a probe of mitochondrial DNA. Sequencing of internal transcribed spacers 1 and 2 (ITS1 and ITS2) revealed three different ITS lengths and four different sequence types. Phylogenetic analysis based on ITS1 sequences, including type strains of different species, clustered the 17 biocontrol strains into four groups: T. harzianum-T. inhamatum complex, T. longibrachiatum, T. asperellum, and T. atroviride-T. koningii complex. ITS2 sequences were also useful for locating the biocontrol strains in T. atroviride within the complex T. atroviride-T. koningii. None of the biocontrol strains studied corresponded to biotypes Th2 or Th4 of T. harzianum, which cause mushroom green mold. Correlation between different genotypes and potential biocontrol activity was studied under dual culturing of 17 BCAs in the presence of the phytopathogenic fungi Phoma betae, Rosellinia necatrix, Botrytis cinerea, and Fusarium oxysporum f. sp. dianthi in three different media. PMID:10788356

  19. Genomic Encyclopedia of Fungi

    SciTech Connect

    Grigoriev, Igor

    2012-08-10

    Genomes of fungi relevant to energy and environment are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). Its key project, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts), and explores fungal diversity by means of genome sequencing and analysis. Over 150 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such parts suggested by comparative genomics and functional analysis in these areas are presented here.

  20. Inhibition of mycotoxin-producing fungi by Bacillus strains isolated from fish intestines.

    PubMed

    Veras, Flávio Fonseca; Correa, Ana Paula Folmer; Welke, Juliane Elisa; Brandelli, Adriano

    2016-12-05

    Bacillus strains isolated from the aquatic environment of the Brazilian Amazon region were tested for their activity against mycotoxigenic fungi. All tested bacteria showed antifungal activity, inhibiting at least 7 indicator fungi. Four Bacillus strains showing promising antifungal results were subsequently evaluated for their activity in reducing mycelial growth rate, sporulation, spore germination percentage, and mycotoxin production. Bacillus sp. P1 and Bacillus sp. P11 had a remarkable antifungal effect on toxigenic fungi. Washed bacterial cell suspension of strains P1 and P11 (10(7)CFU/ml) reduced by >70% the fungal colony diameters, including a complete inhibition of ochratoxin A (OTA) producing Aspergillus spp. Significant reduction of growth rate, sporulation and spore germination were also observed. The bacteria influenced the production of mycotoxins, causing a reduction around 99 and 97% in AFB1 and OTA concentration, respectively. Chromatographic analysis revealed the presence of lipopeptides (iturin A and surfactin isomers) in butanol extracts of cell-free supernatants and cell pellets of strains P1 and P11. Furthermore, antifungal activity of these extracts was confirmed against A. flavus A12 and A. carbonarius ITAL293, producers of AFB1 and OTA, respectively. These bacterial strains could be promising biocontrol agents against toxigenic fungi. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. A new cultivation method for microbial oil production: cell pelletization and lipid accumulation by Mucor circinelloides.

    PubMed

    Xia, Chunjie; Zhang, Jianguo; Zhang, Weidong; Hu, Bo

    2011-06-02

    The recent energy crisis has triggered significant attention on the microbial synthesis of lipids, which comprise the raw material for biodiesel production. Microbial oil accumulation with filamentous fungi has great potential because filamentous fungi can form pellets during cell growth, and these pellets are much easier to harvest from cell broth. This paper focuses on the cell pelletization process of the oleaginous Mucor circinelloides. We have studied the effect of various cultural conditions on pelletized cell growth and lipid accumulation. This study is the first to report that pH adjustment during cell growth plays a key role in pellet formation of M. circinelloides and describes a handy method by which to induce cell pelletization in submerged fungal cultivation. Our study reveals that cell growth and lipid production are not significantly affected by pelletization and that lipid accumulation is triggered at stressed conditions, such as a high carbon-to-nitrogen ratio and high temperature.

  2. Genetically Engineering Entomopathogenic Fungi.

    PubMed

    Zhao, H; Lovett, B; Fang, W

    2016-01-01

    Entomopathogenic fungi have been developed as environmentally friendly alternatives to chemical insecticides in biocontrol programs for agricultural pests and vectors of disease. However, mycoinsecticides currently have a small market share due to low virulence and inconsistencies in their performance. Genetic engineering has made it possible to significantly improve the virulence of fungi and their tolerance to adverse conditions. Virulence enhancement has been achieved by engineering fungi to express insect proteins and insecticidal proteins/peptides from insect predators and other insect pathogens, or by overexpressing the pathogen's own genes. Importantly, protein engineering can be used to mix and match functional domains from diverse genes sourced from entomopathogenic fungi and other organisms, producing insecticidal proteins with novel characteristics. Fungal tolerance to abiotic stresses, especially UV radiation, has been greatly improved by introducing into entomopathogens a photoreactivation system from an archaean and pigment synthesis pathways from nonentomopathogenic fungi. Conversely, gene knockout strategies have produced strains with reduced ecological fitness as recipients for genetic engineering to improve virulence; the resulting strains are hypervirulent, but will not persist in the environment. Coupled with their natural insect specificity, safety concerns can also be mitigated by using safe effector proteins with selection marker genes removed after transformation. With the increasing public concern over the continued use of synthetic chemical insecticides and growing public acceptance of genetically modified organisms, new types of biological insecticides produced by genetic engineering offer a range of environmentally friendly options for cost-effective control of insect pests. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Deuterium pellet injector gun design

    SciTech Connect

    Lunsford, R.V.; Wysor, R.B.; Bryan, W.E.; Shipley, W.D.; Combs, S.K.; Foust, C.R.; Milora, S.L.; Fisher, P.W.

    1985-01-01

    The Deuterium Pellet Injector (DPI), an eight-pellet pneumatic injector, is being designed and fabricated for the Tokamak Fusion Test Reactor (TFTR). It will accelerate eight pellets, 4 by 4 mm maximum, to greater than 1500 m/s. It utilizes a unique pellet-forming mechanism, a cooled pellet storage wheel, and improved propellant gas scavenging.

  4. Pellet inspection apparatus

    DOEpatents

    Wilks, Robert S.; Taleff, Alexander; Sturges, Jr., Robert H.

    1982-01-01

    Apparatus for inspecting nuclear fuel pellets in a sealed container for diameter, flaws, length and weight. The apparatus includes, in an array, a pellet pick-up station, four pellet inspection stations and a pellet sorting station. The pellets are delivered one at a time to the pick-up station by a vibrating bowl through a vibrating linear conveyor. Grippers each associated with a successive pair of the stations are reciprocable together to pick up a pellet at the upstream station of each pair and to deposit the pellet at the corresponding downstream station. The gripper jaws are opened selectively depending on the state of the pellets at the stations and the particular cycle in which the apparatus is operating. Inspection for diameter, flaws and length is effected in each case by a laser beam projected on the pellets by a precise optical system while each pellet is rotated by rollers. Each laser and its optical system are mounted in a container which is free standing on a precise surface and is provided with locating buttons which engage locating holes in the surface so that each laser and its optical system is precisely set. The roller stands are likewise free standing and are similarly precisely positioned. The diameter optical system projects a thin beam of light which scans across the top of each pellet and is projected on a diode array. The fl GOVERNMENT CONTRACT CLAUSE The invention herein described was made in the course of or under a contract or subcontract thereunder with the Department of Energy bearing No. EY-67-14-C-2170.

  5. Carbonaceous pellets and method of pelletizing

    SciTech Connect

    Dondelewski, M.A.

    1982-11-02

    A method is claimed for pelletizing carbonaceous materials including bonding coal fines and lignite coal with a polymeric hydrocarbon binder having reactive sites thereon. For example, with tall oil pitch and the like, in the case of coal, the binder is applied by slurrying the fine coal with the pitch. In the case of lignite, the binder is directly applied to the pulverized material. By action of rolling and tumbling, for example, large agglomerates are formed. With drying and heating, strong water-resistant pellets are formed which have the extremely desirable property of being easily repulverized.

  6. Reciprocating pellet press

    DOEpatents

    Jones, Charles W.

    1981-04-07

    A machine for pressing loose powder into pellets using a series of reciprocating motions has an interchangeable punch and die as its only accurately machines parts. The machine reciprocates horizontally between powder receiving and pressing positions. It reciprocates vertically to press, strip and release a pellet.

  7. Potential biocontrol actinobacteria: Rhizospheric isolates from the Argentine Pampas lowlands legumes.

    PubMed

    Solans, Mariana; Scervino, Jose Martin; Messuti, María Inés; Vobis, Gernot; Wall, Luis Gabriel

    2016-11-01

    Control of fungal plant diseases by using naturally occurring non-pathogenic microorganisms represents a promising approach to biocontrol agents. This study reports the isolation, characterization, and fungal antagonistic activity of actinobacteria from forage soils in the Flooding Pampa, Argentina. A total of 32 saprophytic strains of actinobacteria were obtained by different isolation methods from rhizospheric soil of Lotus tenuis growing in the Salado River Basin. Based on physiological traits, eight isolates were selected for their biocontrol-related activities such as production of lytic extracellular enzymes, siderophores, hydrogen cyanide (HCN), and antagonistic activity against Cercospora sojina, Macrophomia phaseolina, Phomopsis sp., Fusarium oxysporum, and Fusarium verticilloides. These actinobacteria strains were characterized morphologically, physiologically, and identified by using molecular techniques. The characterization of biocontrol-related activities in vitro showed positive results for exoprotease, phospholipase, fungal growth inhibition, and siderophore production. However, none of the strains was positive for the production of hydrogen cyanide (HCN). Streptomyces sp. MM140 presented the highest index for biocontrol, and appear to be promising pathogenic fungi biocontrol agents. These results show the potential capacity of actinobacteria isolated from forage soils in the Argentine Pampas lowlands as promising biocontrol agents, and their future agronomic applications.

  8. Molecular-based strategies to exploit Pseudomonas biocontrol strains for environmental biotechnology applications.

    PubMed

    Mark, Genevievel; Morrissey, John P; Higgins, P; O'gara, Fergal

    2006-05-01

    Exploitation of beneficial plant-microbe interactions in the rhizosphere can result in the promotion of plant health and have significant implications for low input sustainable agriculture applications such as biocontrol. Bacteria such as Bacillus and Pseudomonas, and fungi such as Trichoderma, have been developed as commercial biocontrol products. Registration of microbial inocualants as biocontrol agents in either the European Union or the United States requires production of extensive dossiers covering efficacy, safety and risk assessment. Despite the fact that a number of Pseudomonas biocontrol products have been marketed there are still some limitations hampering the development of this technology for widespread use in agriculture. Although many strains show good performance in specific trials, this is often not translated into consistent, effective biocontrol in diverse field situations. Advances in 'Omics' technology and the publication of complete genome sequences of a number of plant-associative bacterial strains, has facilitated investigations into the molecular basis underpinning the establishment of beneficial plant-microbe interactions in the rhizosphere. The understanding of these molecular signalling processes and the functions they regulate is fundamental to promoting beneficial microbe-plant interactions, to overcome existing limitations and to designing improved strategies for the development of novel Pseudmonas biocontrol inoculant consortia.

  9. Novel fungal pelletization-assisted technology for algae harvesting and wastewater treatment.

    PubMed

    Zhou, Wenguang; Cheng, Yanling; Li, Yun; Wan, Yiqin; Liu, Yuhuan; Lin, Xiangyang; Ruan, Roger

    2012-05-01

    A novel fungi pelletization-assisted bioflocculation technology was developed for efficient algae harvesting and wastewater treatment. Microalga Chlorella vulgaris UMN235 and two locally isolated fungal species Aspergillus sp. UMN F01 and UMN F02 were used to study the effect of various cultural conditions on pelletization process for fungi-algae complex. The results showed that pH was the key factor affecting formation of fungi-algae pellet, and pH could be controlled by adjusting glucose concentration and fungal spore number added. The best pelletization happened when adding 20 g/L glucose and approximately 1.2E8/L spores in BG-11 medium, under which almost 100% of algal cells were captured onto the pellets with shorter retention time. The fungi-algae pellets can be easily harvested by simple filtration due to its large size (2-5 mm). The filtered fungi-algae pellets were reused as immobilized cells for treatment wastewaters and the nutrient removal rates of 100, 58.85, 89.83, and 62.53 % (for centrate) and 23.23, 44.68, 84.70, and 70.34% (for diluted swine manure wastewater) for ammonium, total nitrogen, total phosphorus, and chemical oxygen demand, respectively, under both 1- and 2-day cultivations. The novel technology developed is highly promising compared with current algae harvesting and biological wastewater treatment technologies in the literature.

  10. Whole genome shotgun sequence of Bacillus amyloliquefaciens TF28, a biocontrol entophytic bacterium.

    PubMed

    Zhang, Shumei; Jiang, Wei; Li, Jing; Meng, Liqiang; Cao, Xu; Hu, Jihua; Liu, Yushuai; Chen, Jingyu; Sha, Changqing

    2016-01-01

    Bacillus amyloliquefaciens TF28 is a biocontrol endophytic bacterium that is capable of inhibition of a broad range of plant pathogenic fungi. The strain has the potential to be developed into a biocontrol agent for use in agriculture. Here we report the whole-genome shotgun sequence of the strain. The genome size of B. amyloliquefaciens TF28 is 3,987,635 bp which consists of 3754 protein-coding genes, 65 tandem repeat sequences, 47 minisatellite DNA, 2 microsatellite DNA, 63 tRNA, 7rRNA, 6 sRNA, 3 prophage and CRISPR domains.

  11. Pellet plant energy simulator

    NASA Astrophysics Data System (ADS)

    Bordeasu, D.; Vasquez Pulido, T.; Nielsen, C.

    2016-02-01

    The Pellet Plant energy simulator is a software based on advanced algorithms which has the main purpose to see the response of a pellet plant regarding certain location conditions. It combines energy provided by a combined heat and power, and/or by a combustion chamber with the energy consumption of the pellet factory and information regarding weather conditions in order to predict the biomass consumption of the pellet factory together with the combined heat and power, and/or with the biomass consumption of the combustion chamber. The user of the software will not only be able to plan smart the biomass acquisition and estimate its cost, but also to plan smart the preventive maintenance (charcoal cleaning in case of a gasification plant) and use the pellet plant at the maximum output regarding weather conditions and biomass moisture. The software can also be used in order to execute a more precise feasibility study for a pellet plant in a certain location. The paper outlines the algorithm that supports the Pellet Plant Energy Simulator idea and presents preliminary tests results that supports the discussion and implementation of the system

  12. Lignite pellets and methods of agglomerating or pelletizing

    DOEpatents

    Baker, Albert F.; Blaustein, Eric W.; Deurbrouck, Albert W.; Garvin, John P.; McKeever, Robert E.

    1981-01-01

    The specification discloses lignite pellets which are relatively hard, dust resistant, of generally uniform size and free from spontaneous ignition and general degradation. Also disclosed are methods for making such pellets which involve crushing as mined lignite, mixing said lignite with a binder such as asphalt, forming the lignite binder mixture into pellets, and drying the pellets.

  13. Mobile Biomass Pelletizing System

    SciTech Connect

    Thomas Mason

    2009-04-16

    This grant project examines multiple aspects of the pelletizing process to determine the feasibility of pelletizing biomass using a mobile form factor system. These aspects are: the automatic adjustment of the die height in a rotary-style pellet mill, the construction of the die head to allow the use of ceramic materials for extreme wear, integrating a heat exchanger network into the entire process from drying to cooling, the use of superheated steam for adjusting the moisture content to optimum, the economics of using diesel power to operate the system; a break-even analysis of estimated fixed operating costs vs. tons per hour capacity. Initial development work has created a viable mechanical model. The overall analysis of this model suggests that pelletizing can be economically done using a mobile platform.

  14. Radation shielding pellets

    DOEpatents

    Coomes, Edmund P.; Luksic, Andrzej T.

    1988-12-06

    Radiation pellets having an outer shell, preferably, of Mo, W or depleted U nd an inner filling of lithium hydride wherein the outer shell material has a greater melting point than does the inner filling material.

  15. Pneumatic Pellet-Transporting System

    NASA Technical Reports Server (NTRS)

    Wood, George; Pugsley, Robert A.

    1992-01-01

    Pneumatic system transports food pellets to confined animals. Flow of air into venturi assembly entrains round pellets, drawing them from reservoir into venturi for transport by airflow. Pneumatic pellet-transporting system includes venturi assembly, which creates flow of air that draws pellets into system.

  16. Pneumatic Pellet-Transporting System

    NASA Technical Reports Server (NTRS)

    Wood, George; Pugsley, Robert A.

    1992-01-01

    Pneumatic system transports food pellets to confined animals. Flow of air into venturi assembly entrains round pellets, drawing them from reservoir into venturi for transport by airflow. Pneumatic pellet-transporting system includes venturi assembly, which creates flow of air that draws pellets into system.

  17. Is Quorum Signaling by Mycotoxins a New Risk-Mitigating Strategy for Bacterial Biocontrol of Fusarium verticillioides and Other Endophytic Fungal Species?

    PubMed

    Bacon, Charles W; Hinton, Dorothy M; Mitchell, Trevor R

    2017-08-23

    Bacterial endophytes are used as biocontrol organisms for plant pathogens such as the maize endophyte Fusarium verticillioides and its production of fumonisin mycotoxins. However, such applications are not always predictable and efficient. In this work, we hypothesize and review work that quorum sensing inhibitors are produced either by fungi or by pathogenic bacteria for competitive purposes, altering the efficiency of the biocontrol organisms. Recently, quorum sensing inhibitors have been isolated from several fungi, including Fusarium species, three of which are mycotoxins. Thus, we further postulate that other mycotoxins are inhibitors or quenching metabolites that prevent the protective abilities and activities of endophytic biocontrol bacteria within intercellular spaces. To test the aforementioned suppositions, we review work detailing the use of bioassay bacteria for several mycotoxins for quorum activity. We specifically focus on the quorum use of endophytic bacteria as biocontrols for mycotoxic fungal endophytes, such as the Fusarium species and the fumonisin mycotoxins.

  18. The Asian Wood Pellet Markets

    Treesearch

    Joseph A. Roos; Allen Brackley

    2012-01-01

    This study examines the three major wood pellet markets in Asia: China, Japan, and South Korea. In contrast to the United States, where most wood pellets are used for residential heating with pellet stoves, a majority of the wood pellets in Asia are used for co-firing at coal-fired power plants. Our analysis indicated that Japan is the largest importer of wood pellets...

  19. Myco-Biocontrol of Insect Pests: Factors Involved, Mechanism, and Regulation

    PubMed Central

    Sandhu, Sardul Singh; Sharma, Anil K.; Beniwal, Vikas; Goel, Gunjan; Batra, Priya; Kumar, Anil; Jaglan, Sundeep; Sharma, A. K.; Malhotra, Sonal

    2012-01-01

    The growing demand for reducing chemical inputs in agriculture and increased resistance to insecticides have provided great impetus to the development of alternative forms of insect-pest control. Myco-biocontrol offers an attractive alternative to the use of chemical pesticides. Myco-biocontrol agents are naturally occurring organisms which are perceived as less damaging to the environment. Their mode of action appears little complex which makes it highly unlikely that resistance could be developed to a biopesticide. Past research has shown some promise of the use of fungi as a selective pesticide. The current paper updates us about the recent progress in the field of myco-biocontrol of insect pests and their possible mechanism of action to further enhance our understanding about the biological control of insect pests. PMID:22567344

  20. Pellet formation of zygomycetes and immobilization of yeast.

    PubMed

    Nyman, Jonas; Lacintra, Michael G; Westman, Johan O; Berglin, Mattias; Lundin, Magnus; Lennartsson, Patrik R; Taherzadeh, Mohammad J

    2013-06-25

    Pelleted growth provides many advantages for filamentous fungi, including decreased broth viscosity, improved aeration, stirring, and heat transfer. Thus, the factors influencing the probability of pellet formation of Rhizopus sp. in a defined medium was investigated using a multifactorial experimental design. Temperature, agitation intensity, Ca(2+)-concentration, pH, and solid cellulose particles, each had a significant effect on pelletization. Tween 80, spore concentration, and liquid volume were not found to have a significant effect. All of the effects were additive; no interactions were significant. The results were used to create a simple defined medium inducing pelletization, which was used for immobilization of a flocculating strain of Saccharomyces cerevisiae in the zygomycetes pellets. A flor-forming S. cerevisiae strain was also immobilized, while a non-flocculating strain colonized the pellets but was not immobilized. No adverse effects were detected as a result of the close proximity between the filamentous fungus and the yeast, which potentially allows for co-fermentation with S. cerevisiae immobilized in pellets of zygomycetes.

  1. The Potential of Streptomyces as Biocontrol Agents against the Rice Blast Fungus, Magnaporthe oryzae (Pyricularia oryzae)

    PubMed Central

    Law, Jodi Woan-Fei; Ser, Hooi-Leng; Khan, Tahir M.; Chuah, Lay-Hong; Pusparajah, Priyia; Chan, Kok-Gan; Goh, Bey-Hing; Lee, Learn-Han

    2017-01-01

    Rice is a staple food source for more than three billion people worldwide. However, rice is vulnerable to diseases, the most destructive among them being rice blast, which is caused by the fungus Magnaporthe oryzae (anamorph Pyricularia oryzae). This fungus attacks rice plants at all stages of development, causing annual losses of approximately 10–30% in various rice producing regions. Synthetic fungicides are often able to effectively control plant diseases, but some fungicides result in serious environmental and health problems. Therefore, there is growing interest in discovering and developing new, improved fungicides based on natural products as well as introducing alternative measures such as biocontrol agents to manage plant diseases. Streptomyces bacteria appear to be promising biocontrol agents against a wide range of phytopathogenic fungi, which is not surprising given their ability to produce various bioactive compounds. This review provides insight into the biocontrol potential of Streptomyces against the rice blast fungus, M. oryzae. The ability of various Streptomyces spp. to act as biocontrol agents of rice blast disease has been studied by researchers under both laboratory and greenhouse/growth chamber conditions. Laboratory studies have shown that Streptomyces exhibit inhibitory activity against M. oryzae. In greenhouse studies, infected rice seedlings treated with Streptomyces resulted in up to 88.3% disease reduction of rice blast. Studies clearly show that Streptomyces spp. have the potential to be used as highly effective biocontrol agents against rice blast disease; however, the efficacy of any biocontrol agent may be affected by several factors including environmental conditions and methods of application. In order to fully exploit their potential, further studies on the isolation, formulation and application methods of Streptomyces along with field experiments are required to establish them as effective biocontrol agents. PMID:28144236

  2. The Potential of Streptomyces as Biocontrol Agents against the Rice Blast Fungus, Magnaporthe oryzae (Pyricularia oryzae).

    PubMed

    Law, Jodi Woan-Fei; Ser, Hooi-Leng; Khan, Tahir M; Chuah, Lay-Hong; Pusparajah, Priyia; Chan, Kok-Gan; Goh, Bey-Hing; Lee, Learn-Han

    2017-01-01

    Rice is a staple food source for more than three billion people worldwide. However, rice is vulnerable to diseases, the most destructive among them being rice blast, which is caused by the fungus Magnaporthe oryzae (anamorph Pyricularia oryzae). This fungus attacks rice plants at all stages of development, causing annual losses of approximately 10-30% in various rice producing regions. Synthetic fungicides are often able to effectively control plant diseases, but some fungicides result in serious environmental and health problems. Therefore, there is growing interest in discovering and developing new, improved fungicides based on natural products as well as introducing alternative measures such as biocontrol agents to manage plant diseases. Streptomyces bacteria appear to be promising biocontrol agents against a wide range of phytopathogenic fungi, which is not surprising given their ability to produce various bioactive compounds. This review provides insight into the biocontrol potential of Streptomyces against the rice blast fungus, M. oryzae. The ability of various Streptomyces spp. to act as biocontrol agents of rice blast disease has been studied by researchers under both laboratory and greenhouse/growth chamber conditions. Laboratory studies have shown that Streptomyces exhibit inhibitory activity against M. oryzae. In greenhouse studies, infected rice seedlings treated with Streptomyces resulted in up to 88.3% disease reduction of rice blast. Studies clearly show that Streptomyces spp. have the potential to be used as highly effective biocontrol agents against rice blast disease; however, the efficacy of any biocontrol agent may be affected by several factors including environmental conditions and methods of application. In order to fully exploit their potential, further studies on the isolation, formulation and application methods of Streptomyces along with field experiments are required to establish them as effective biocontrol agents.

  3. Production of zinc pellets

    SciTech Connect

    Cooper, J.F.

    1996-11-26

    Uniform zinc pellets are formed for use in batteries having a stationary or moving slurry zinc particle electrode. The process involves the cathodic deposition of zinc in a finely divided morphology from battery reaction product onto a non-adhering electrode substrate. The mossy zinc is removed from the electrode substrate by the action of gravity, entrainment in a flowing electrolyte, or by mechanical action. The finely divided zinc particles are collected and pressed into pellets by a mechanical device such as an extruder, a roller and chopper, or a punch and die. The pure zinc pellets are returned to the zinc battery in a pumped slurry and have uniform size, density and reactivity. Applications include zinc-air fuel batteries, zinc-ferricyanide storage batteries, and zinc-nickel-oxide secondary batteries. 6 figs.

  4. Production of zinc pellets

    DOEpatents

    Cooper, John F.

    1996-01-01

    Uniform zinc pellets are formed for use in batteries having a stationary or moving slurry zinc particle electrode. The process involves the cathodic deposition of zinc in a finely divided morphology from battery reaction product onto a non-adhering electrode substrate. The mossy zinc is removed from the electrode substrate by the action of gravity, entrainment in a flowing electrolyte, or by mechanical action. The finely divided zinc particles are collected and pressed into pellets by a mechanical device such as an extruder, a roller and chopper, or a punch and die. The pure zinc pellets are returned to the zinc battery in a pumped slurry and have uniform size, density and reactivity. Applications include zinc-air fuel batteries, zinc-ferricyanide storage batteries, and zinc-nickel-oxide secondary batteries.

  5. Production of zinc pellets

    DOEpatents

    Cooper, J.F.

    1996-11-26

    Uniform zinc pellets are formed for use in batteries having a stationary or moving slurry zinc particle electrode. The process involves the cathodic deposition of zinc in a finely divided morphology from battery reaction product onto a non-adhering electrode substrate. The mossy zinc is removed from the electrode substrate by the action of gravity, entrainment in a flowing electrolyte, or by mechanical action. The finely divided zinc particles are collected and pressed into pellets by a mechanical device such as an extruder, a roller and chopper, or a punch and die. The pure zinc pellets are returned to the zinc battery in a pumped slurry and have uniform size, density and reactivity. Applications include zinc-air fuel batteries, zinc-ferricyanide storage batteries, and zinc-nickel-oxide secondary batteries. 6 figs.

  6. Modeling pellet impact drilling process

    NASA Astrophysics Data System (ADS)

    Kovalyov, A. V.; Ryabchikov, S. Ya; Isaev, Ye D.; Ulyanova, O. S.

    2016-03-01

    The paper describes pellet impact drilling which could be used to increase the drilling speed and the rate of penetration when drilling hard rocks. Pellet impact drilling implies rock destruction by metal pellets with high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are circulated in the bottom hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The experiments conducted has allowed modeling the process of pellet impact drilling, which creates the scientific and methodological basis for engineering design of drilling operations under different geo-technical conditions.

  7. Genetic engineering of fungal biocontrol agents to achieve greater efficacy against insect pests.

    PubMed

    St Leger, Raymond J; Wang, Chengshu

    2010-01-01

    Molecular biology methods have elucidated pathogenic processes in several fungal biocontrol agents including two of the most commonly applied entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana. In this review, we describe how a combination of molecular techniques has: (1) identified and characterized genes involved in infection; (2) manipulated the genes of the pathogen to improve biocontrol performance; and (3) allowed expression of a neurotoxin from the scorpion Androctonus australis. The complete sequencing of four exemplar species of entomopathogenic fungi including B. bassiana and M. anisopliae will be completed in 2010. Coverage of these genomes will help determine the identity, origin, and evolution of traits needed for diverse lifestyles and host switching. Such knowledge combined with the precision and malleability of molecular techniques will allow design of multiple pathogens with different strategies to be used for different ecosystems and avoid the possibility of the host developing resistance.

  8. The filamentous fungal pellet and forces driving its formation.

    PubMed

    Zhang, Jianguo; Zhang, Jining

    2016-12-01

    Filamentous fungi play an important role not only in the bio-manufacturing of value-added products, but also in bioenergy and environmental research. The bioprocess manipulation of filamentous fungi is more difficult than that of other microbial species because of their different pellet morphologies and the presence of tangled mycelia under different cultivation conditions. Fungal pellets, which have the advantages of harvest ease, low fermentation broth viscosity and high yield of some proteins, have been used for a long time. Many attempts have been made to establish the relationship between pellet and product yield using quantitative approaches. Fungal pellet formation is attributed to the combination of electrostatic interactions, hydrophobicity and specific interactions from spore wall components. Electrostatic interactions result from van der Waals forces and negative charge repulsion from carboxyl groups in the spore wall structure. Electrostatic interactions are also affected by counter-ions (cations) and the physiologic conditions of spores that modify the carboxyl groups. Fungal aggregates are promoted by the hydrophobicity generated by hydrophobins, which form a hydrophobic coat that covers the spore. The specific interactions of spore wall components contribute to spore aggregation through salt bridging. A model of spore aggregation was proposed based on these forces. Additionally, some challenges were addressed, including the limitations of research techniques, the quantitative determination of forces and the complex information of biological systems, to clarify the mechanism of fungal pellet formation.

  9. Owl Pellet Paleontology

    ERIC Educational Resources Information Center

    McAlpine, Lisa K.

    2013-01-01

    In this activity for the beginning of a high school Biology 1 evolution unit, students are challenged to reconstruct organisms found in an owl pellet as a model for fossil reconstruction. They work in groups to develop hypotheses about what animal they have found, what environment it inhabited, and what niche it filled. At the end of the activity,…

  10. Owl Pellet Paleontology

    ERIC Educational Resources Information Center

    McAlpine, Lisa K.

    2013-01-01

    In this activity for the beginning of a high school Biology 1 evolution unit, students are challenged to reconstruct organisms found in an owl pellet as a model for fossil reconstruction. They work in groups to develop hypotheses about what animal they have found, what environment it inhabited, and what niche it filled. At the end of the activity,…

  11. Bacteriophage biocontrol of foodborne pathogens.

    PubMed

    Kazi, Mustafa; Annapure, Uday S

    2016-03-01

    Bacteriophages are viruses that only infect bacterial cells. Phages are categorized based on the type of their life cycle, the lytic cycle cause lysis of the bacterium with the release of multiple phage particles where as in lysogenic phase the phage DNA is incorporated into the bacterial genome. Lysogeny does not result in lysis of the host. Lytic phages have several potential applications in the food industry as biocontrol agents, biopreservatives and as tools for detecting pathogens. They have also been proposed as alternatives to antibiotics in animal health. Two unique features of phage relevant for food safety are that they are harmless to mammalian cells and high host specificity, keeping the natural microbiota undisturbed. However, the recent approval of bacteriophages as food additives has opened the discussion about 'edible viruses'. This article reviews in detail the application of phages for the control of foodborne pathogens in a process known as "biocontrol".

  12. Repulsion of Meloidogyne incognita by Alginate Pellets Containing Hyphae of Monacrosporium cionopagum, M. ellipsosporum, or Hirsutella rhossiliensis.

    PubMed

    Robinson, A F; Jaffee, B A

    1996-06-01

    The responses of second-stage juveniles (J2) of Meloidogyne incognita race 3 to calcium alginate pellets containing hyphae of the nematophagous fungi Monacrosporiura cionopagum, M. ellipsosporum, and Hirsutella rhossiliensis were examined using cylinders (38-mm-diam., 40 or 72 mm long) of sand (94% <250-mum particle size). Sand was wetted with a synthetic soil solution (10% moisture, 0.06 bar water potential). A layer of 10 or 20 pellets was placed 4 or 20 mm from one end of the cylinder. After 3, 5, or 13 days, J2 were put on both ends, on one end, or in the center; J2 were extracted from 8-ram-thick sections 1 or 2 days later. All three fungal pellets were repellent; pellets without fungi were not. Aqueous extracts of all pellets and of sand in which fungal pellets had been incubated were repellent, but acetone extracts redissolved in water were not. Injection of CO (20 mul/minute) into the pellet layer attracted J2 and increased fungal-induced mortality. In vials containing four randomly positioned pellets and 17 cm(3) of sand or loamy sand, the three fungi suppressed the invasion of cabbage roots by M. javanica J2. Counts of healthy and parasitized nematodes observed in roots or extracted from soil indicated that, in the vial assay, the failure of J2 to penetrate roots resulted primarily from parasitism rather than repulsion. Data were similar whether fungal inoculum consisted of pelletized hyphae or fungal-colonized Steinernema glaseri. Thus, the results indicate that nematode attractants and repellents can have major or negligible effects on the biological control efficacy of pelletized nematophagous fungi. Factors that might influence the importance of substances released by the pellets include the strength, geometry, and duration of gradients; pellet degradation by soil microflora; the nematode species involved; and attractants released by roots.

  13. Managing the plant microbiome for biocontrol fungi: Examples from Hypocreales

    USDA-ARS?s Scientific Manuscript database

    Feeding an increasing global population requires continued improvements in agricultural efficiency and productivity. Meeting estimated future production levels requires the adoption of practices that increase output without environmental degradation associated with external inputs to supplement nut...

  14. Thermal Properties of Lignocellulose Pellets

    NASA Astrophysics Data System (ADS)

    Wachter, Igor; Hirle, Siegfried; Balog, Karol

    2017-06-01

    This article deals with the characterization of biomass pellets using Differential Scanning Calorimetry. We used three types of industrially produced and commercially available pellets as samples: wood pellets containing grass, wood pellet containing bark and wood pellets without bark. Each of the samples were examined using the DSC method. Based on the measurements in atmosphere of air and nitrogen temperature, the changes caused by thermal degradation of various kinds of test fuels were observed. Subsequently, limits of exothermic processes, reaction enthalpy changes and the temperature at which exothermic reactions reached peaks were determined.

  15. Pellet imaging techniques on ASDEX

    SciTech Connect

    Wurden, G.A. ); Buechl, K.; Hofmann, J.; Lang, R.; Loch, R.; Rudyj, A.; Sandmann, W. )

    1990-01-01

    As part of a USDOE/ASDEX collaboration, a detailed examination of pellet ablation in ASDEX with a variety of diagnostics has allowed a better understanding of a number of features of hydrogen ice pellet ablation in a plasma. In particular, fast gated photos with an intensified Xybion CCD video camera allow in-situ velocity measurements of the pellet as it penetrates the plasma. With time resolution of typically 100 nanoseconds and exposures every 50 microseconds, the evolution of each pellet in a multi-pellet ASDEX tokamak plasma discharge can be followed. When the pellet cloud track has striations, the light intensity profile through the cloud is hollow (dark near the pellet), whereas at the beginning or near the end of the pellet trajectory the track is typically smooth (without striations) and has a gaussian-peaked light emission profile. New, single pellet Stark broadened D{sub {alpha}}D{sub {beta}}, and D{sub {gamma}} spectra, obtained with a tangentially viewing scanning mirror/spectrometer with Reticon array readout, are consistent with cloud densities of 2 {times} 10{sup 17}cm{sup {minus}3} or higher in the regions of strongest light emission. A spatially resolved array of D{sub {alpha}} detectors shows that the light variations during the pellet ablation are not caused solely by a modulation of the incoming energy flux as the pellet crosses rational q-surfaces, but instead are a result of a dynamic, non-stationary, ablation process. 20 refs., 4 figs.

  16. Postharvest Biocontrol: Introspection and Paradigm Shifts

    USDA-ARS?s Scientific Manuscript database

    The use of postharvest biocontrol agents as an alternative to the synthetic, chemical fungicides on a widespread basis has many constraints. During the last twenty years, the field of postharvest biocontrol research has significantly grown and developed and seen the creation of several products. Des...

  17. Toxins of filamentous fungi.

    PubMed

    Bhatnagar, Deepak; Yu, Jiujiang; Ehrlich, Kenneth C

    2002-01-01

    designed to develop natural biocontrol competitive fungi and to enhance host resistance against fungal growth or toxin production. These efforts could prevent toxin formation entirely. Rigorous programs for reducing the risk of human and animal exposure to contaminated foods and feed also include economically feasible and safe detoxification processes and dietary modifications. Although risk assessment has been made for some mycotoxins, additional, systematic epidemological data for human exposure is needed for establishing toxicological parameters for mycotoxins and the safe dose for humans. It is unreasonable to expect complete elimination of the mycotoxin problem. But multiple approaches will be needed to minimize the economic impact of the toxins on the entire agriculture industry and their harmfulness to human and animal health.

  18. Genetics of Cordyceps and related fungi.

    PubMed

    Zheng, Peng; Xia, Yongliang; Zhang, Siwei; Wang, Chengshu

    2013-04-01

    Ascomycete Cordyceps sensu lato consists of hundreds of species of fungi capable of infecting different insects. Species of these fungi are either valued traditional Chinese medicines or used for biocontrol of insect pests. Phylogenomic analysis indicated that fungal entomopathogenicity has evolved for multiple times, and the species of Cordyceps were diverged from the mycoparasite or plant endophyte. Relative to plant pathogens and saprophytes, Cordyceps species demonstrate characteristic genome expansions of proteases and chitinases that are used by the fungi to target insect cuticles. Only a single mating-type gene identified in the sequenced species of Cordyceps sensu lato indicates that these fungi are sexually heterothallic, but the gene structure of the mating-type loci and frequency in performing sexual cycle are considerably different between different species. Similar to the model fungus Neurospora crassa, Cordyceps and related fungi contain the full components for RNA interference pathways. However, the mechanism of repeat-induced point mutation varies between different fungi. Epigenetic rather than genetic alterations are majorly responsible for the frequent occurrence of culture degeneration in Cordyceps-related species. Future genetic and epigenetic studies of fungal sexuality controls and culture degeneration mechanisms will benefit the cost-effective applications of Cordyceps and related fungi in pharmaceuticals and agriculture.

  19. Characterization of a new isolate of Pseudomonas fluorescens strain Psd as a potential biocontrol agent.

    PubMed

    Upadhyay, A; Srivastava, S

    2008-08-01

    Evaluation of a new isolate of Pseudomonas fluorescens for its biocontrol properties. Strain Psd identified as Ps. fluorescens, produces secondary metabolites that are toxic to some plant-pathogenic fungi. Inhibition of fungal growth of Fusarium oxysporum and Verticillium dahliae in the presence of bacterial culture filtrate provided the first clue to its biocontrol properties. In order to determine the basis for antifungal properties, antibiotics were extracted and analysed by TLC. Both pyrrolnitrin and phenazines could be detected in the culture of Psd. Presence of response regulator gene gacA of the two component regulatory system (GacS/GacA) was established by PCR amplification and sequencing. Sequence comparison of gacA justified the taxonomic position of this strain among the known members of Pseudomonadaceae. Synthesis of other compounds like toxic lipodepsipeptide, siderophores, and HCN was also confirmed by appropriate biochemical tests. Characterization of strain Psd by various biochemical/plate tests followed by chromatographic identification of antibiotics, demonstrates its multifunctional biocontrol property. Response regulator gene gacA provides an additional genetic marker for the phylogenetic studies. Ps. fluorescens strain Psd with its multifunctional biocontrol property can be used to bioprotect the crop plants from phytopathogens.

  20. Pellet interaction with runaway electrons

    SciTech Connect

    James, A. N.; Hollmann, E. M.; Yu, J.H.; Austin, M. E.; Commaux, Nicolas JC; Evans, T.E.; Humphrey, D. A.; Jernigan, T. C.; Parks, P. B.; Putvinski, S.; Strait, E. J.; Tynan, G. R.; Wesley, J. C.

    2011-01-01

    We describe results from recent experiments studying interaction of solid polystyrene pellets with a runaway electron current channel generated after cryogenic argon pellet rapid shutdown of DIII-D. Fast camera imaging shows the pellet trajectory and continuum emission from the subsequent explosion, with geometric calibration providing detailed explosion analysis and runaway energy. Electron cyclotron emission also occurs, associated with knock-on electrons broken free from the pellet by RE which then accelerate and runaway, and also with a short lived hot plasma blown off the pellet surface. In addition, we compare heating and explosion times from observations and a model of pellet heating and breakdown by runaway interaction. (C) 2011 Elsevier B.V. All rights reserved

  1. Preliminary in vitro insights into the use of natural fungal pathogens of leaf-cutting ants as biocontrol agents.

    PubMed

    Folgarait, Patricia; Gorosito, Norma; Poulsen, Michael; Currie, Cameron R

    2011-09-01

    Leaf-cutting ants are one of the main herbivores of the Neotropics, where they represent an important agricultural pest. These ants are particularly difficult to control because of the complex network of microbial symbionts. Leaf-cutting ants have traditionally been controlled through pesticide application, but there is a need for alternative, more environmentally friendly, control methods such as biological control. Potential promising biocontrol candidates include the microfungi Escovopsis spp. (anamorphic Hypocreales), which are specialized pathogens of the fungi the ants cultivate for food. These pathogens are suppressed through ant behaviors and ant-associated antibiotic-producing Actinobacteria. In order to be an effective biocontrol agent, Escovopsis has to overcome these defenses. Here, we evaluate, using microbial in vitro assays, whether defenses in the ant-cultivated fungus strain (Leucoagaricus sp.) and Actinobacteria from the ant pest Acromyrmex lundii have the potential to limit the use of Escovopsis in biocontrol. We also explore, for the first time, possible synergistic biocontrol between Escovopsis and the entomopathogenic fungus Lecanicillium lecanii. All strains of Escovopsis proved to overgrow A. lundii cultivar in less than 7 days, with the Escovopsis strain isolated from a different leaf-cutting ant species being the most efficient. Escovopsis challenged with a Streptomyces strain isolated from A. lundii did not exhibit significant growth inhibition. Both results are encouraging for the use of Escovopsis as a biocontrol agent. Although we found that L. lecanii can suppress the growth of the cultivar, it also had a negative impact on Escovopsis, making the success of simultaneous use of these two fungi for biocontrol of A. lundii questionable.

  2. Potential role of exoglucanase genes (WaEXG1 and WaEXG2) in the biocontrol activity of Wickerhamomyces anomalous

    USDA-ARS?s Scientific Manuscript database

    The use of yeasts, including Wickerhamomyces anomalus, as biocontrol agents against fungi responsible for postharvest diseases of fruits and vegetables has been investigated for the past two decades. Among a variety of killer mechanisms, the production of glucanases coded by the genes WaEXG1 and Wa...

  3. Pellet injector research at ORNL

    SciTech Connect

    Schuresko, D.D.; Milora, S.L.; Combs, S.K.; Foster, C.A.; Fisher, P.W.; Argo, B.E.; Barber, G.C.; Foust, C.R.; Gethers, F.E.; Gouge, M.J.

    1987-01-01

    Several advanced plasma fueling systems are under development at the Oak Ridge National Laboratory (ORNL) for present and future magnetic confinement devices. These include multishot and repeating pneumatic pellet injectors, centrifuge accelerators, electrothermal guns, a Tritium Proof-of-Principle experiment, and an ultrahigh velocity mass ablation driven accelerator. A new eight-shot pneumatic injector capable of delivering 3.0 mm, 3.5 mm, and 4.0 mm diameter pellets at speeds up to 1500 m/s into a single discharge has been commissioned recently on the Tokamak Fusion Test reactor. The so-called Deuterium Pellet Injector (DPI) is a prototype of a Tritium Pellet Injector (TPI) scheduled for use on TFTR in 1990. Construction of the TPI will be preceded by a test of tritium pellet fabrication and acceleration using a 4 mm bore ''pipe gun'' apparatus. A new repeating pneumatic pellet injector capable of 2.7 mm, 4 mm, and 6 mm operation is being installed on the Joint European Torus to be used in ORNL/JET collaborative pellet injection studies. A 1.5 m centrifuge injector is being developed for application on the Tore Supra experiment in 1988. The new device, which is a 50% upgrade of the prototype centrifuge used on D-III, features a pellet feed mechanism capable of producing variable-size pellets (1.5 to 3.0 mm diameter) optimally shaped to survive acceleration stresses. Accelerating pellets to velocities in excess of 2 km/s is being pursued through two new development undertakings. A hydrogen plasma electrothermal gun is operational at 2 km/s with 10 mg hydrogen pellets; this facility has recently been equipped with a pulsed power supply capable of delivering 1.7 kJ millisecond pulses to low impedence arc loads.

  4. ORNL centrifuge pellet fueling system

    SciTech Connect

    Foster, C.A.; Houlberg, W.A.; Gouge, M.J.; Grapperhaus, M.J.; Milora, S.L. ); Drawin, H.; Geraud, A.; Chatelier, M.; Gros, G. )

    1992-01-01

    A centrifuge pellet injecter designed and built at Oak Ridge National Laboratory (ORNL) is in operation on Tore Supra. This injector has the capability of injecting up to 100 pellets at speeds up to 800 M/s. The solid deuterium pellets can be formed with a variable mass from 3 to 10 torr-L and are fired at a rate of up to 10 pellets per second. The experimental program that is under way combines repetitive pellet fueling with the ergodic divertor and pump limiters to establish and understand long-pulse plasmas in which the pellet fuel source is in balance with the particle exhaust. With lower hybrid current drive, pulse lengths of up to 2 min might be achieved. To prepare for these extended pulse lengths, the pellet source on the centrifuge will be extended to provide a 300- to 500-pellet capability. A similar system extended to steady-state pellet fabrication technology and designed for a radiation and tritium environment would be a candidate for a fueling system for the International Thermonuclear Experimental Reactor (ITER). Analysis of pellet-fueled ITER discharges using the WHIST code shows the potential for controlling the radial fuel deposition point to achieve the desired core density while maintaining the edge density and temperatures so as to minimize the diverter plate erosion. A centrifuge fueling system would have the capability of taking the D-T exhaust directly from the cryopumping systems, recondensing and purifying the fuel, and injecting the reconstituted pellets into the plasma, thereby minimizing the tritium inventory.

  5. ORNL centrifuge pellet fueling system

    SciTech Connect

    Foster, C.A.; Houlberg, W.A.; Gouge, M.J.; Grapperhaus, M.J.; Milora, S.L.; Drawin, H.; Geraud, A.; Chatelier, M.; Gros, G.

    1992-11-01

    A centrifuge pellet injecter designed and built at Oak Ridge National Laboratory (ORNL) is in operation on Tore Supra. This injector has the capability of injecting up to 100 pellets at speeds up to 800 M/s. The solid deuterium pellets can be formed with a variable mass from 3 to 10 torr-L and are fired at a rate of up to 10 pellets per second. The experimental program that is under way combines repetitive pellet fueling with the ergodic divertor and pump limiters to establish and understand long-pulse plasmas in which the pellet fuel source is in balance with the particle exhaust. With lower hybrid current drive, pulse lengths of up to 2 min might be achieved. To prepare for these extended pulse lengths, the pellet source on the centrifuge will be extended to provide a 300- to 500-pellet capability. A similar system extended to steady-state pellet fabrication technology and designed for a radiation and tritium environment would be a candidate for a fueling system for the International Thermonuclear Experimental Reactor (ITER). Analysis of pellet-fueled ITER discharges using the WHIST code shows the potential for controlling the radial fuel deposition point to achieve the desired core density while maintaining the edge density and temperatures so as to minimize the diverter plate erosion. A centrifuge fueling system would have the capability of taking the D-T exhaust directly from the cryopumping systems, recondensing and purifying the fuel, and injecting the reconstituted pellets into the plasma, thereby minimizing the tritium inventory.

  6. Owl Pellets and Crisis Management.

    ERIC Educational Resources Information Center

    Anderson, Tom

    2002-01-01

    Describes a press conference that was used as a "teachable moment" when owl pellets being used for instructional purposes were found to be contaminated with Salmonella. The incident highlighted the need for safe handling of owl pellets, having a crisis management plan, and the importance of conveying accurate information to concerned parents.…

  7. Owl Pellets and Crisis Management.

    ERIC Educational Resources Information Center

    Anderson, Tom

    2002-01-01

    Describes a press conference that was used as a "teachable moment" when owl pellets being used for instructional purposes were found to be contaminated with Salmonella. The incident highlighted the need for safe handling of owl pellets, having a crisis management plan, and the importance of conveying accurate information to concerned parents.…

  8. Pelletizing properties of torrefied spruce

    Treesearch

    Wolfgang Stelte; Craig Clemons; Jens K. Holm; Anand R. Sanadi; Jesper Ahrenfeldt; Lei Shang; Ulrik B. Henriksen

    2011-01-01

    Torrefaction is a thermo-chemical conversion process improving the handling, storage and combustion properties of wood. To save storage space and transportation costs, it can be compressed into fuel pellets of high physical and energetic density. The resulting pellets are relatively resistant to moisture uptake, microbiological decay and easy to comminute into small...

  9. Automated fuel pellet inspection system

    NASA Astrophysics Data System (ADS)

    Lichauer, John C.; Zana, Larry J.

    1992-11-01

    In the nuclear fuels industry, a great deal of effort goes into ensuring that quality materials are produced. Of these materials, none receives more attention than the uranium-oxide nuclear fuel pellets. These cylindrically shaped pellets (approx. 1/2 inch L X 1/2 inch D) are carefully produced and then meticulously inspected for various defects (e.g., cracks, chips, etc.). The inspection process is designed to remove any defective pellets from each lot, assuring the end user a reliable, predictable, and safe product. The current (manual) inspection process is laborious and subjective in nature. The inspector also receives prolonged exposure to low-level radiation. For these reasons, automated inspection of nuclear fuel pellets has long been a goal of the industry. However, it is not a simple task, due to the many material handling and image processing challenges required to inspect pellets at production rates (greater than five per second). This paper describes an automated nuclear fuel pellet inspection system that has successfully met these challenges. Built around a set of modular, high-speed, pipelined image processing hardware, it inspects pellets at rates of up to seven pellets per second. Recent tests have shown better than 97% detection rates with less than 2% false reject rates. Image processing algorithms and solutions to design challenges are described.

  10. Initial NSTX Lithium Pellet Injection

    NASA Astrophysics Data System (ADS)

    Kugel, H. W.; Bell, M.; Bell, R.; Biewer, T.; Gates, D.; Jardin, S.; Kaita, R.; Leblanc, B.; Paul, S.; Samtaney, R.; Skinner, C. H.; Raman, R.; Bush, C.; Maingi, R.; Soukhanovskii, V.; Nishino, N.; Lee, K. C.; Stutman, D.

    2004-11-01

    A cartridge style Lithium Pellet Injector was installed on NSTX for midplane radial injection. Deuterium gas was used to propel a Li pellet-bearing cartridge down a barrel to a cartridge stop, and the pellet continued into the NSTX plasma at about 150 m/s. 16 lithium pellets, about 2 mg each were injected into LSN and DND, NBI-heated, H-mode plasmas, and into L-mode LSN Ohmic plasmas, and were observed with a Li I filtered Plasma-TV. Li pellets injected into NBI-heated LSN and DND plasmas appeared to ablate in the outer boundary. The pellets injected into OH plasmas exhibited good penetration to the HFS region. Lastly, a NBI preheat was added prior to pellet arrival, and the penetration depth was found to be very sensitive to the NBI turn-off time relative to pellet arrival. As this work progressed, Li luminosity started to be observed from the very initiation of discharges, due to depositions from preceding discharges. Initial modeling results will be presented.

  11. Nuclear fuel pellet transfer escalator

    SciTech Connect

    Huggins, T.B. Sr.; Roberts, E.; Edmunds, M.O.

    1991-09-17

    This patent describes a nuclear fuel pellet escalator for loading nuclear fuel pellets into a sintering boat. It comprises a generally horizontally-disposed pellet transfer conveyor for moving pellets in single file fashion from a receiving end to a discharge end thereof, the conveyor being mounted about an axis at its receiving end for pivotal movement to generally vertically move its discharge end toward and away from a sintering boat when placed below the discharge end of the conveyor, the conveyor including an elongated arm swingable vertically about the axis and having an elongated channel recessed below an upper side of the arm and extending between the receiving and discharge ends of the conveyor; a pellet dispensing chute mounted to the arm of the conveyor at the discharge end thereof and extending therebelow such that the chute is carried at the discharge end of the conveyor for generally vertical movement therewith toward and away from the sintering boat.

  12. Entomopathogenic Fungi on Hemiberlesia pitysophila

    PubMed Central

    Lv, Chengqun; Huang, Baoling; Qiao, Mengji; Wei, Jiguang; Ding, Bo

    2011-01-01

    Hemiberlesia pitysophila Takagi is an extremely harmful exotic insect in forest to Pinus species, including Pinus massoniana. Using both morphological taxonomy and molecular phylogenetics, we identified 15 strains of entomogenous fungi, which belong to 9 genera with high diversities. Surprisingly, we found that five strains that were classified as species of Pestalotiopsis, which has been considered plant pathogens and endophytes, were the dominant entomopathogenic fungus of H. pitysophila. Molecular phylogenetic tree established by analyzing sequences of ribosomal DNA internal transcribed spacer showed that entomopathogenic Pestalotiopsis spp. were similar to plant Pestalotiopsis, but not to other pathogens and endophytes of its host plant P. massoniana. We were the first to isolate entomopathogenic Pestalotiopsis spp. from H. pitysophila. Our findings suggest a potential and promising method of H. pitysophila bio-control. PMID:21901126

  13. Enhancement of Biocontrol Activities and Cyclic Lipopeptides Production by Chemical Mutagenesis of Bacillus subtilis XF-1, a Biocontrol Agent of Plasmodiophora brassicae and Fusarium solani.

    PubMed

    Li, Xing-Yu; Yang, Jing-Jing; Mao, Zi-Chao; Ho, Hon-Hing; Wu, Yi-Xing; He, Yue-Qiu

    2014-12-01

    Bacillus subtilis XF-1 has been used as a biocontrol agent of clubroot disease of crucifers infected by Plasmodiophora brassicae, an obligate pathogen. In order to maximize the growth inhibition of the pathogen, random mutagenesis using N-methyl-N'-nitro-N-nitrosoguanidine was applied to strain XF-1. The efficacy of 226 selected mutants was assessed against the growth of an indicator fungal pathogen: Fusarium solani using agar plate assay and the disruptive effects on the resting spores of P. brassicae. Four mutants exhibited inhibition activity significantly higher than the wild type. The cell extracts of these mutants and the XF-1 were subjected to matrix-assisted laser desorption ionization-time of flight mass spectra analysis, and three families of cyclic lipopeptides (CLPs) fengycin, surfactin and iturin were identified from the parental strain and the screened mutants. However, the relative contents and compound diversity changed after mutagenesis, and there was slight variation in the surfactin and fengycin. Notably, only 5 iturin components were discovered from the wild strain XF-1, but 13 were obtained from the mutant strains, and the relative CLPs contents of all mutant strains increased substantially. The results suggested that CLPs might be one of main biocontrol mechanisms of the clubroot disease by XF-1. The 4 mutants are far more effective than the parental strain, and they would be promising biocontrol candidates not only against P. brassicae but probably other plant diseases caused by fungi.

  14. Research on biodeterioration of wood, 1987-1992. 1. Decay mechanisms and biocontrol. Forest Service research paper

    SciTech Connect

    Highley, T.L.; Clausen, C.A.; Croan, S.C.; Green, F.; Illman, B.L.

    1994-03-01

    Growing concerns about the environment present an urgent need for new approaches to preserving wood. Some commonly used preservatives have been banned or restricted in several countries. The research paper first describes current knowledge about how white-and-brown rot fungi decay wood and then delineates research in to problem areas: (1) control of wood decay through targeting biosynthetic and degradative pathways, and (2) biological control (biocontrol) of wood decay through non-decay micro-organisms.

  15. Effect of heat shock treatment on stress tolerance and biocontrol efficacy of biocontrol yeasts

    USDA-ARS?s Scientific Manuscript database

    Several different species of yeasts have been used as biocontrol agents against postharvest diseases of fruits and vegetables. Our current research is directed to develop a better understanding of yeast biology in relation to biocontrol activity and to develop strategies to improve the efficacy of ...

  16. Nonribosomal peptides, key biocontrol components for Pseudomonas fluorescens In5, isolated from a Greenlandic suppressive soil.

    PubMed

    Michelsen, Charlotte F; Watrous, Jeramie; Glaring, Mikkel A; Kersten, Roland; Koyama, Nobuhiro; Dorrestein, Pieter C; Stougaard, Peter

    2015-03-17

    Potatoes are cultivated in southwest Greenland without the use of pesticides and with limited crop rotation. Despite the fact that plant-pathogenic fungi are present, no severe-disease outbreaks have yet been observed. In this report, we document that a potato soil at Inneruulalik in southern Greenland is suppressive against Rhizoctonia solani Ag3 and uncover the suppressive antifungal mechanism of a highly potent biocontrol bacterium, Pseudomonas fluorescens In5, isolated from the suppressive potato soil. A combination of molecular genetics, genomics, and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) imaging mass spectrometry (IMS) revealed an antifungal genomic island in P. fluorescens In5 encoding two nonribosomal peptides, nunamycin and nunapeptin, which are key components for the biocontrol activity by strain In5 in vitro and in soil microcosm experiments. Furthermore, complex microbial behaviors were highlighted. Whereas nunamycin was demonstrated to inhibit the mycelial growth of R. solani Ag3, but not that of Pythium aphanidermatum, nunapeptin instead inhibited P. aphanidermatum but not R. solani Ag3. Moreover, the synthesis of nunamycin by P. fluorescens In5 was inhibited in the presence of P. aphanidermatum. Further characterization of the two peptides revealed nunamycin to be a monochlorinated 9-amino-acid cyclic lipopeptide with similarity to members of the syringomycin group, whereas nunapeptin was a 22-amino-acid cyclic lipopeptide with similarity to corpeptin and syringopeptin. Crop rotation and systematic pest management are used to only a limited extent in Greenlandic potato farming. Nonetheless, although plant-pathogenic fungi are present in the soil, the farmers do not experience major plant disease outbreaks. Here, we show that a Greenlandic potato soil is suppressive against Rhizoctonia solani, and we unravel the key biocontrol components for Pseudomonas fluorescens In5, one of the potent biocontrol bacteria

  17. Tritium pellet injector for TFTR

    SciTech Connect

    Gouge, M.J.; Baylor, L.R.; Cole, M.J.; Combs, S.K.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foust, C.R.; Langley, R.A.; Milora, S.L.; Qualls, A.L.; Wilgen, J.B.; Schmidt, G.L.; Barnes, G.W.; Persing, R.G.

    1992-06-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) phase. The existing TFTR deuterium pellet injector (DPI) has been modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed to provide pellets ranging from 3.3 to 4.5 mm in diameter in arbitrarily programmable firing sequences at speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller. The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed, and the TPI was tested at ORNL with deuterium pellet. Results of the limited testing program at ORNL are described. The TPI is being installed on TFTR to support the D-D run period in 1992. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and secondary tritium containment systems and integrated into TFTR tritium processing systems to provide full tritium pellet capability.

  18. Tritium pellet injector for TFTR

    SciTech Connect

    Gouge, M.J.; Baylor, L.R.; Cole, M.J.; Combs, S.K.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foust, C.R.; Langley, R.A.; Milora, S.L.; Qualls, A.L.; Wilgen, J.B. ); Schmidt, G.L.; Barnes, G.W.; Persing, R.G. . Plasma Physics Lab.)

    1992-01-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) phase. The existing TFTR deuterium pellet injector (DPI) has been modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed to provide pellets ranging from 3.3 to 4.5 mm in diameter in arbitrarily programmable firing sequences at speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller. The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed, and the TPI was tested at ORNL with deuterium pellet. Results of the limited testing program at ORNL are described. The TPI is being installed on TFTR to support the D-D run period in 1992. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and secondary tritium containment systems and integrated into TFTR tritium processing systems to provide full tritium pellet capability.

  19. Influence of oxygen on lovastatin biosynthesis by Aspergillus terreus ATCC 20542 quantitatively studied on the level of individual pellets.

    PubMed

    Bizukojc, Marcin; Gonciarz, Joanna

    2015-07-01

    Despite oxygen is believed to be the most important environmental factor for any aerobic microbial process, the quantitative studies of its influence on growth and metabolite formation on the level of individual pellets formed by filamentous fungi were seldom performed. Never was it made for lovastatin producer Aspergillus terreus ATCC20542. Thus, this work is a quantitative study of oxygen transfer into A. terreus pellets during lovastatin biosynthesis in the shake flask culture. The basic measurement tool was an oxygen microprobe allowing for obtaining oxygen concentration profiles in the pellets. The pellets of various sizes from 1,600 to 6,400 μm exerting different oxygen transfer conditions were studied. Also various initial concentrations of carbon source were applied to change the conditions of biological reaction running in the pellets. Effective diffusivities in A. terreus pellets ranged from 643 to 1,342 μm s(-1) dependent on their size and structure. It occurred that only the smallest pellets of diameter equal to about 1,400 μm were fully penetrated by oxygen. What is more, apart from the size of pellets, the appropriate lactose concentration was required to effectively produce lovastatin. Its value was correlated with oxygen concentration on the surface of the pellet and could not be either too high, as the aforementioned oxygen level tended then to zero, or too low, as despite high oxygen concentration no biological reaction ran in the pellet and no lovastatin was formed.

  20. Simulation of Pellet Ablation

    NASA Astrophysics Data System (ADS)

    Parks, P. B.; Ishizaki, Ryuichi

    2000-10-01

    In order to clarify the structure of the ablation flow, 2D simulation is carried out with a fluid code solving temporal evolution of MHD equations. The code includes electrostatic sheath effect at the cloud interface.(P.B. Parks et al.), Plasma Phys. Contr. Fusion 38, 571 (1996). An Eulerian cylindrical coordinate system (r,z) is used with z in a spherical pellet. The code uses the Cubic-Interpolated Psudoparticle (CIP) method(H. Takewaki and T. Yabe, J. Comput. Phys. 70), 355 (1987). that divides the fluid equations into non-advection and advection phases. The most essential element of the CIP method is in calculation of the advection phase. In this phase, a cubic interpolated spatial profile is shifted in space according to the total derivative equations, similarly to a particle scheme. Since the profile is interpolated by using the value and the spatial derivative value at each grid point, there is no numerical oscillation in space, that often appears in conventional spline interpolation. A free boundary condition is used in the code. The possibility of a stationary shock will also be shown in the presentation because the supersonic ablation flow across the magnetic field is impeded.

  1. Pellet injection into ATF plasmas

    SciTech Connect

    Wilgen, J.B.; Bell, J.D.; England, A.C.; Fisher, P.W.; Howe, H.C.; Murakami, M.; Rasmussen, D.A.; Richards, R.K.; Uckan, T.; Wing, W.R. ); Bell, G.L. ); Qualls, A.L. ); Sudo, S. )

    1990-01-01

    Based on the favorable empirical scaling of stellarator confinement with increasing electron density, pellet fueling is expected to result in significant performance improvement of the ATF plasma. With gas-puff fueling, NBI heated plasmas in ATF are limited by a thermal collapse. Pellet fueling provides a potential means to delay this effect and gain access to the favorable high density confinement regime. To provide flexibility for optimization and physics studies, eight different pellet sizes are available. To date, line average densities of up to 4 {times} 10{sup 13} cm{sup {minus}3} have been achieved with a single pellet injected into a 0.7 MW NBI plasma at 0.95 T; the results from optimization studies with up to 1.5 MW of NBI power at 2 T will be presented.

  2. North America's wood pellet sector

    Treesearch

    Henry Spelter; Daniel Toth

    2009-01-01

    The North American wood pellet sector is profiled in this paper. A small pellet industry has existed since the 1930s, but its main growth occurred in the wake of the energy crisis in the 1970s. Its current spurt is even greater, growing from is set to reach 6.2 million in 2009. Most plants are small, relying on sawmill residues for fiber and thus are limited to 100,000...

  3. [Fungal bio-control agents against ixodid tick--a review].

    PubMed

    Sun, Ming; Wang, Xiaoyan; Luo, Jianxun

    2012-08-04

    Entomopathogenic fungi as potential agents for bio-control have been widely applied in the control of insect pests in agriculture. However, the application remains in laboratory scale for the control of ectoparasites. Owing to the need to combat the short lasting period of chemical acaricides and reduction of pollution, it is urgent to develop sufficient, stable and safe measures for tick control. We reviewed the primary scientific achievements in utilization of environmental microbes for controlling of ticks. Studies conducted in this field may benefit to sustainable development, environmental protection, maintaining ecological balance and production of green products.

  4. Solid deuterium centrifuge pellet injector

    SciTech Connect

    Foster, C.A.

    1982-01-01

    Pellet injectors are needed to fuel long pulse tokamak plasmas and other magnetic confinement devices. For this purpose, an apparatus has been developed that forms 1.3-mm-diam pellets of frozen deuterium at a rate of 40 pellets per second and accelerates them to a speed of 1 km/s. Pellets are formed by extruding a billet of solidified deuterium through a 1.3-mm-diam nozzle at a speed of 5 cm/s. The extruding deuterium is chopped with a razor knife, forming 1.3-mm right circular cylinders of solid deuterium. The pellets are accelerated by synchronously injecting them into a high speed rotating arbor containing a guide track, which carries them from a point near the center of rotation to the periphery. The pellets leave the wheel after 150/sup 0/ of rotation at double the tip speed. The centrifuge is formed in the shape of a centrifugal catenary and is constructed of high strength KEVLAR/epoxy composite. This arbon has been spin-tested to a tip speed of 1 km/s.

  5. 46 CFR 148.325 - Wood chips; wood pellets; wood pulp pellets.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Wood chips; wood pellets; wood pulp pellets. 148.325... § 148.325 Wood chips; wood pellets; wood pulp pellets. (a) This part applies to wood chips and wood pulp... cargo hold. (b) No person may enter a cargo hold containing wood chips, wood pellets, or wood...

  6. 46 CFR 148.325 - Wood chips; wood pellets; wood pulp pellets.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Wood chips; wood pellets; wood pulp pellets. 148.325... § 148.325 Wood chips; wood pellets; wood pulp pellets. (a) This part applies to wood chips and wood pulp... cargo hold. (b) No person may enter a cargo hold containing wood chips, wood pellets, or wood...

  7. 46 CFR 148.325 - Wood chips; wood pellets; wood pulp pellets.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Wood chips; wood pellets; wood pulp pellets. 148.325... § 148.325 Wood chips; wood pellets; wood pulp pellets. (a) This part applies to wood chips and wood pulp... cargo hold. (b) No person may enter a cargo hold containing wood chips, wood pellets, or wood...

  8. 46 CFR 148.325 - Wood chips; wood pellets; wood pulp pellets.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Wood chips; wood pellets; wood pulp pellets. 148.325... § 148.325 Wood chips; wood pellets; wood pulp pellets. (a) This part applies to wood chips and wood pulp... cargo hold. (b) No person may enter a cargo hold containing wood chips, wood pellets, or wood...

  9. 46 CFR 148.04-21 - Coconut meal pellets (also known as copra pellets).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Coconut meal pellets (also known as copra pellets). 148.04-21 Section 148.04-21 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DANGEROUS... § 148.04-21 Coconut meal pellets (also known as copra pellets). (a) Coconut meal pellets; (1) Must...

  10. Efficacy of entomopathogenic hypocrealean fungi against Periplaneta americana.

    PubMed

    Hubner-Campos, Rayssa Fátima; Leles, Renan Nunes; Rodrigues, Juscelino; Luz, Christian

    2013-12-01

    The American cockroach Periplaneta americana, one of the worlds' most important urban insect pests was tested with entomopathogenic fungi. Most promising Metarhizium anisopliae, Metarhizium robertsii and Beauveria bassiana killed nymphs (≥ 81.7% mortality, 25 days after treatment), and these fungi developed on all dead insects. Other fungi tested were less virulent (Metarhizium frigidum and Purpureocillium lilacinum) or avirulent (Isaria cateniobliqua, Isaria farinosa, Simplicillium lanosoniveum, Sporothrix insectorum and Tolypocladium cylindrosporum). Intrageneric and intraspecific variability of fungal activity was detected. Adults were highly susceptible, and oothecae proved to be more resistant than nymphs and adults to infection with M. anisopliae IP 46. Findings of the study underscore the potential of fungi as biocontrol agents against this pest.

  11. Complementary effects of torrefaction and co-pelletization: Energy consumption and characteristics of pellets.

    PubMed

    Cao, Liang; Yuan, Xingzhong; Li, Hui; Li, Changzhu; Xiao, Zhihua; Jiang, Longbo; Huang, Binbin; Xiao, Zhihong; Chen, Xiaohong; Wang, Hou; Zeng, Guangming

    2015-06-01

    In this study, complementary of torrefaction and co-pelletization for biomass pellets production was investigated. Two kinds of biomass materials were torrefied and mixed with oil cake for co-pelletization. The energy consumption during pelletization and pellet characteristics including moisture absorption, pellet density, pellet strength and combustion characteristic, were evaluated. It was shown that torrefaction improved the characteristics of pellets with high heating values, low moisture absorption and well combustion characteristic. Furthermore, co-pelletization between torrefied biomass and cater bean cake can reduce several negative effects of torrefaction such as high energy consumption, low pellet density and strength. The optimal conditions for energy consumption and pellet strength were torrefied at 270°C and a blending with 15% castor bean cake for both biomass materials. The present study indicated that compelmentary performances of the torrefaction and co-pelletization with castor bean cake provide a promising alternative for fuel production from biomass and oil cake.

  12. Application of terminal restriction fragment length polymorphism (T-RFLP) analysis to monitor effect of biocontrol agents on rhizosphere microbial community of hot pepper (Capsicum annuum L.).

    PubMed

    Kim, Young Tae; Cho, Myoungho; Jeong, Je Yong; Lee, Hyang Burm; Kim, Seung Bum

    2010-10-01

    Microbial communities in hot pepper (Capsicum annuum L.) cultivation fields under different cultivation methods were investigated by terminal restriction fragment length polymorphism (T-RFLP) analysis. Rhizosphere soil and leaf samples were collected from control, conventional and nature-friendly cultivation fields between May and July, 2009. Two Bacillus subtilis strains were applied to nature-friendly cultivation fields as biocontrol agents during the sampling period. Relative abundances of bacteria and plant pathogenic fungi related T-RFs were also measured to monitor the effect of biocontrol agents on potential plant pathogenic fungi. In the principal component analysis (PCA) based on T-RFLP profiles, the microbial communities from rhizosphere soil samples in July, including bacteria and fungi, showed distinct difference between nature-friendly cultivation fields and other cultivation fields. However, there was no correlation between cultivation methods and leaf microbial communities at any sampling period. Changes in the abundance of bacteria related T-RF in the rhizosphere of nature-friendly cultivation fields were observed clearly two months after application of biocontrol agent, while the abundance of plant pathogenic fungi related T-RFs significantly decreased.

  13. Biocontrol agents promote growth of potato pathogens, depending on environmental conditions.

    PubMed

    Cray, Jonathan A; Connor, Mairéad C; Stevenson, Andrew; Houghton, Jonathan D R; Rangel, Drauzio E N; Cooke, Louise R; Hallsworth, John E

    2016-05-01

    There is a pressing need to understand and optimize biological control so as to avoid over-reliance on the synthetic chemical pesticides that can damage environmental and human health. This study focused on interactions between a novel biocontrol-strain, Bacillus sp. JC12GB43, and potato-pathogenic Phytophthora and Fusarium species. In assays carried out in vitro and on the potato tuber, the bacterium was capable of near-complete inhibition of pathogens. This Bacillus was sufficiently xerotolerant (water activity limit for growth = 0.928) to out-perform Phytophthora infestans (~0.960) and challenge Fusarium coeruleum (~0.847) and Fusarium sambucinum (~0.860) towards the lower limits of their growth windows. Under some conditions, however, strain JC12GB43 stimulated proliferation of the pathogens: for instance, Fusarium coeruleum growth-rate was increased under chaotropic conditions in vitro (132 mM urea) by >100% and on tubers (2-M glycerol) by up to 570%. Culture-based assays involving macromolecule-stabilizing (kosmotropic) compatible solutes provided proof-of-principle that the Bacillus may provide kosmotropic metabolites to the plant pathogen under conditions that destabilize macromolecular systems of the fungal cell. Whilst unprecedented, this finding is consistent with earlier reports that fungi can utilize metabolites derived from bacterial cells. Unless the antimicrobial activities of candidate biocontrol strains are assayed over a full range of field-relevant parameters, biocontrol agents may promote plant pathogen infections and thereby reduce crop yields. These findings indicate that biocontrol activity, therefore, ought to be regarded as a mode-of-behaviour (dependent on prevailing conditions) rather than an inherent property of a bacterial strain. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  14. The Global Regulator Genes from Biocontrol Strain Serratia plymuthica IC1270: Cloning, Sequencing, and Functional Studies†

    PubMed Central

    Ovadis, Marianna; Liu, Xiaoguang; Gavriel, Sagi; Ismailov, Zafar; Chet, Ilan; Chernin, Leonid

    2004-01-01

    The biocontrol activity of various fluorescent pseudomonads towards plant-pathogenic fungi is dependent upon the GacA/GacS-type two-component system of global regulators and the RpoS transcription sigma factor. In particular, these components are required for the production of antifungal antibiotics and exoenzymes. To investigate the effects of these global regulators on the expression of biocontrol factors by plant-associated bacteria other than Pseudomonas spp., gacA/gacS and rpoS homologues were cloned from biocontrol strain IC1270 of Serratia plymuthica, which produces a set of antifungal compounds, including chitinolytic enzymes and the antibiotic pyrrolnitrin. The nucleotide and deduced protein sequence alignments of the cloned gacA/gacS-like genes—tentatively designated grrA (global response regulation activator) and grrS (global response regulation sensor) and of the cloned rpoS gene revealed 64 to 93% identity with matching genes and proteins of the enteric bacteria Escherichia coli, Pectobacterium carotovora subsp. carotovora, and Serratia marcescens. grrA, grrS, and rpoS gene replacement mutants of strain IC1270 were deficient in the production of pyrrolnitrin, an exoprotease, and N-acylhomoserine lactone quorum-sensing signal molecules. However, neither mutant appeared to differ from the parental strain in the production of siderophores, and only grrA and grrS mutants were deficient in the production of a 58-kDa endochitinase, representing the involvement of other sigma factors in the regulation of strain IC1270's chitinolytic activity. Compared to the parental strain, the grrA, grrS, and rpoS mutants were markedly less capable of suppressing Rhizoctonia solani and Pythium aphanidermatum under greenhouse conditions, indicating the dependence of strain IC1270's biocontrol property on the GrrA/GrrS and RpoS global regulators. PMID:15262936

  15. A mathematical model to predict the size of the pellets formed in freeze pelletization techniques: parameters affecting pellet size.

    PubMed

    Cheboyina, Sreekhar; O'Haver, John; Wyandt, Christy M

    2006-01-01

    A mathematical model was developed based on the theory of drop formation to predict the size of the pellets formed in the freeze pelletization process. Further the model was validated by studying the effect of various parameters on the pellet size such as viscosity of the pellet forming and column liquids, surface/interfacial tension, density difference between pellet forming and column liquids; size, shape, and material of construction of the needle tips and temperatures maintained in the columns. In this study, pellets were prepared from different matrices including polyethylene glycols and waxes. The column liquids studied were silicone oils and aqueous glycerol solutions. The surface/interfacial tension, density difference between pellet forming and column liquids and needle tip size were found to be the most important factors affecting pellet size. The viscosity of the column liquid was not found to significantly affect the size of the pellets. The size of the pellets was also not affected by the pellet forming liquids of low viscosities. An increase in the initial column temperature slightly decreased the pellet size. The mathematical model developed was found to successfully predict the size of the pellets with an average error of 3.32% for different matrices that were studied.

  16. Filamentous Fungi.

    PubMed

    Powers-Fletcher, Margaret V; Kendall, Brian A; Griffin, Allen T; Hanson, Kimberly E

    2016-06-01

    Filamentous mycoses are often associated with significant morbidity and mortality. Prompt diagnosis and aggressive treatment are essential for good clinical outcomes in immunocompromised patients. The host immune response plays an essential role in determining the course of exposure to potential fungal pathogens. Depending on the effectiveness of immune response and the burden of organism exposure, fungi can either be cleared or infection can occur and progress to a potentially fatal invasive disease. Nonspecific cellular immunity (i.e., neutrophils, natural killer [NK] cells, and macrophages) combined with T-cell responses are the main immunologic mechanisms of protection. The most common potential mold pathogens include certain hyaline hyphomycetes, endemic fungi, the Mucorales, and some dematiaceous fungi. Laboratory diagnostics aimed at detecting and differentiating these organisms are crucial to helping clinicians make informed decisions about treatment. The purpose of this chapter is to provide an overview of the medically important fungal pathogens, as well as to discuss the patient characteristics, antifungal-therapy considerations, and laboratory tests used in current clinical practice for the immunocompromised host.

  17. Commercialization of postharvest biocontrol: barriers and opportunities

    USDA-ARS?s Scientific Manuscript database

    The past twenty years has seen the field of postharvest biocontrol evolve from an unknown entity with one or two novel reports in the literature to a sophisticated science with strong research programs worldwide, hundreds of publications, patented technologies, and now several commercial products. ...

  18. Experiments with Biocontrol of Alternaria alternata

    USDA-ARS?s Scientific Manuscript database

    A biocontrol yeast (WRL-76) developed by USDA-ARS at the Western Regional Research lab was evaluated for control of Alternaria alternata on pistachio. The experiment was conducted over a four year period in a Madera Co., CA orchard. Counts of damaged vs. intact fruit clusters were taken on 100 contr...

  19. Carbon requirements of some nematophagous, entomopathogenic and mycoparasitic hyphomycetes as fungal biocontrol agents.

    PubMed

    Sun, ManHong; Liu, XingZhong

    2006-05-01

    Thirty-three carbon sources were evaluated for their effects on spore germination, hyphal growth and sporulation of 11 fungal biocontrol agents, i.e. the nematophagous fungi Paecilomyces lilacinus, Pochonia chlamydosporia, Hirsutella rhossiliensis, H. minnesotensis and Arkansas Fungus 18, the entomopathogenic fungi Lecanicillium lecanii, Beauveria bassiana and Metarhizium anisopliae, and the mycoparasitic fungus Trichoderma viride. Variations in carbon requirements were found among the fungal species or strains tested. All strains studied except for T. viride grew on most carbon sources, although B. bassiana had more fastidious requirements for spore germination. Monosaccharides and disaccharides were suitable for fungal growth. For most isolates, D-glucose, D-mannose, sucrose and trehalose were superior to pectin and soluble starch among the polysaccharides and lactic acid among the organic acids. Both ethanol and methanol could accelerate growth of most isolates but not biomass. D-mannose, D-fructose and D-xylose were excellent carbon sources for sporulation, while D-glucose, sucrose, cellobiose, trehalose, chitin, dextrin, gelatin and lactic acid were better for some isolates. Neither sorbic acid nor linoleic acid could be utilized as a single carbon source. These findings provided a better understanding of the nutritional requirements of different fungal biocontrol agents that can benefit the mass production process.

  20. Reconstruction of the original mycoflora in pelleted feed by PCR-SSCP and qPCR.

    PubMed

    Dorn-In, Samart; Fahn, Carmen; Hölzel, Christina S; Wenz, Sebastian; Hartwig, Isabella; Schwaiger, Karin; Bauer, Johann

    2014-10-01

    Ground feeds for pigs were investigated for fungal contamination before and after pelleting (subsamples in total n = 24) by cultural and molecular biological methods. A fungal-specific primer pair ITS1/ITS5.8R was used to amplify fungal DNA; PCR products were processed for the PCR-SSCP method. In the resulting acrylamide gel, more than 85% of DNA bands of ground feeds were preserved after pelleting. Twenty-two DNA bands were sequenced; all represented fungal DNA. The level of fungal DNA in ground feed samples was equivalent to 4.77-5.69 log10  CFU g(-1) , calculated by qPCR using a standard curve of Aspergillus flavus. In pelleted feed, the level of fungal DNA was in average ± 0.07 log10 different from ground feed. Quantified by cultural methods, the fresh ground feeds contained up to 4.51 log10  CFU g(-1) culturable fungi, while there was < 2.83 log10  CFU g(-1) detected in pelleted feeds. This result shows that, while the process of pelleting reduced the amount of living fungi dramatically, it did not affect the total fungal DNA in feed. Thus, the described methodology was able to reconstruct the fungal microbiota in feeds and reflected a considerable fungal contamination of raw materials such as grains.

  1. Rhizobia: a potential biocontrol agent for soilborne fungal pathogens.

    PubMed

    Das, Krishnashis; Prasanna, Radha; Saxena, Anil Kumar

    2017-03-12

    Rhizobia are a group of organisms that are well known for their ability to colonize root surfaces and form symbiotic associations with legume plants. They not only play a major role in biological nitrogen fixation but also improve plant growth and reduce disease incidence in various crops. Rhizobia are known to control the growth of many soilborne plant pathogenic fungi belonging to different genera like Fusarium, Rhizoctonia, Sclerotium, and Macrophomina. Antagonistic activity of rhizobia is mainly attributed to production of antibiotics, hydrocyanic acid (HCN), mycolytic enzymes, and siderophore under iron limiting conditions. Rhizobia are also reported to induce systemic resistance and enhance expression of plant defense-related genes, which effectively immunize the plants against pathogens. Seed bacterization with appropriate rhizobial strain leads to elicitation and accumulation of phenolic compounds, isoflavonoid phytoalexins, and activation of enzymes like L-phenylalanine ammonia lyase (PAL), chalcone synthase (CHS), peroxidase (POX), polyphenol oxidase (PPO), and others involved in phenylpropanoid and isoflavonoid pathways. Development of Rhizobium inoculants with dual attributes of nitrogen fixation and antagonism against phytopathogens can contribute to increased plant growth and productivity. This compilation aims to bring together the available information on the biocontrol facet of rhizobia and identify research gaps and effective strategies for future research in this area.

  2. Electrothermal plasma gun as a pellet injector

    SciTech Connect

    Kincaid, R.W.; Bourham, M.A.

    1994-11-01

    The NCSU electrothermal plasma gun SIRENS has been used to accelerate plastic (Lexan polycarbonate) pellets, to determine the feasibility of the use of electrothermal guns as pellet injectors. The use of an electrothermal gun to inject frozen hydrogenic pellets requires a mechanism to provide protective shells (sabots) for shielding the pellet from ablation during acceleration into and through the barrel of the gun. The gun has been modified to accommodate acceleration of the plastic pellets using special acceleration barrels equipped with diagnostics for velocity and position of the pellet, and targets to absorb the pellet`s energy on impact. The length of the acceleration path could be varied between 15 and 45 cm. The discharge energy of the electrothermal gun ranged from 2 to 6 kJ. The pellet velocities have been measured via a set of break wires. Pellet masses were varied between 0.5 and 1.0 grams. Preliminary results on 0.5 and 1.0 g pellets show that the exit velocity reaches 0.9 km/s at 6 kJ input energy to the source. Higher velocities of 1.5 and 2.7 km/s have been achieved using 0.5 and 1.0 gm pellets in 30 cm long barrel, without cleaning the barrel between the shots.

  3. Mechanisms Involved in Nematode Control by Endophytic Fungi.

    PubMed

    Schouten, Alexander

    2016-08-04

    Colonization of plants by particular endophytic fungi can provide plants with improved defenses toward nematodes. Evidently, such endophytes can be important in developing more sustainable agricultural practices. The mechanisms playing a role in this quantitative antagonism are poorly understood but most likely multifactorial. This knowledge gap obstructs the progress regarding the development of endophytes or endophyte-derived constituents into biocontrol agents. In part, this may be caused by the fact that endophytic fungi form a rather heterogeneous group. By combining the knowledge of the currently characterized antagonistic endophytic fungi and their effects on nematode behavior and biology with the knowledge of microbial competition and induced plant defenses, the various mechanisms by which this nematode antagonism operates or may operate are discussed. Now that new technologies are becoming available and more accessible, the currently unresolved mechanisms can be studied in greater detail than ever before.

  4. A numerical study of combined use of two biocontrol agents with different biocontrol mechanisms in controlling foliar pathogens.

    PubMed

    Xu, X-M; Jeffries, P; Pautasso, M; Jeger, M J

    2011-09-01

    Effective use of biocontrol agents is an important component of sustainable agriculture. A previous numerical study of a generic model showed that biocontrol efficacy was greatest for a single biocontrol agent (BCA) combining competition with mycoparasitism or antibiosis. This study uses the same mathematical model to investigate whether the biocontrol efficacy of combined use of two BCAs with different biocontrol mechanisms is greater than that of a single BCA with either or both of the two mechanisms, assuming that two BCAs occupy the same host tissue as the pathogen. Within the parameter values considered, a BCA with two biocontrol mechanisms always outperformed the combined use of two BCAs with a single but different biocontrol mechanism. Similarly, combined use of two BCAs with a single but different biocontrol mechanism is shown to be far less effective than that of a single BCA with both mechanisms. Disease suppression from combined use of two BCAs was very similar to that achieved by the more efficacious one. As expected, a higher BCA introduction rate led to increased disease suppression. Incorporation of interactions between two BCAs did not greatly affect the disease dynamics except when a mycoparasitic and, to a lesser extent, an antibiotic-producing BCA was involved. Increasing the competitiveness of a mycoparasitic BCA over a BCA whose biocontrol mechanism is either competition or antibiosis may lead to improved biocontrol initially and reduced fluctuations in disease dynamics. The present study suggests that, under the model assumptions, combined use of two BCAs with different biocontrol mechanisms in most cases only results in control efficacies similar to using the more efficacious one alone. These predictions are consistent with published experimental results, suggesting that combined use of BCAs should not be recommended without clear understanding of their main biocontrol mechanisms and relative competitiveness, and experimental evaluation.

  5. Model for pneumatic pellet injection

    SciTech Connect

    Hogan, J.T.; Milora, S.L.; Schuresko, D.D.

    1983-07-01

    A hydrodynamic code has been developed to model the performance of pneumatic pellet injection systems. The code describes one dimensional, unsteady compressible gas dynamics, including gas friction and heat transfer to the walls in a system with variable area. The mass, momentum, and energy equations are solved with an iterated Lax-Wendroff scheme with additional numerical viscosity. The code is described and comparisons with experimental data are presented.

  6. Fungi and fungal toxins as weapons.

    PubMed

    Paterson, R Russell M

    2006-09-01

    Recent aggressive attacks on innocent citizens have resulted in governments increasing security. However, there is a good case for prevention rather than reaction. Bioweapons, mycotoxins, fungal biocontrol agents (FBCA), and even pharmaceuticals contain, or are, toxins and need to be considered in the context of the new paradigm. Is it desirable to discuss such issues? None of the fungi are (a) as toxic as botulinum toxin from Clostridium botulinum, and (b) as dangerous as nuclear weapons. One toxin may be defined as a pharmaceutical and vice versa simply by a small change in concentration or a moiety. Mycotoxins are defined as naturally occurring toxic compounds obtained from fungi. They are the biggest chronic health risk when incorporated into the diet. The current list of fungal toxins as biochemical weapons is small, although awareness is growing of the threats they may pose. T-2 toxin is perhaps the biggest concern. A clear distinction is required between the biological (fungus) and chemical (toxin) aspects of the issue. There is an obvious requirement to be able to trace these fungi and compounds in the environment and to know when concentrations are abnormal. Many FBCA, produce toxins. This paper indicates how to treat mycotoxicosis and decontaminate mycotoxins. There is considerable confusion and inconsistency surrounding this topic which requires assessment in an impartial and scientific manner.

  7. Biological Control of the Nematode Infective larvae of Trichostrongylidae Family With Filamentous Fungi.

    PubMed

    Zarrin, Majid; Rahdar, Mahmoud; Gholamian, Abbas

    2015-03-01

    Biological control of parasitic nematodes by microorganisms is a promising approach to control such parasites. Microorganisms such as fungi, viruses and bacteria are recognized as biocontrol agents of nematodes. The current study mainly aimed to evaluate the in vitro Potential of various saprophyte soil-fungi in reducing the infective larvae stage of parasitic nematode Trichostrongylidae family. Sheep feces were employed to provide the required third stage larvae source for the experiments. The nematode infective larvae of Trichostrongylidae family including three species of Ostertagia circumcincta, Marshalgia marshali and Heamonchos contortus were collected by Berman apparatus. Fifteen isolates of filamentous fungi were tested in the current study. One milliliter suspension containing 200 third stage larvae of Trichostrongylidae family was separately added to the fungal cultures in 2% water-agar medium Petri-dishes. Every day the live larvae were counted with light microscope (10X) and the number of captured larvae was recorded on different days. Significant differences were observed in the results of co-culture of nematodes larva and fungi after seven days. The most effective fungi against the nematodes larvae were Cladosporium sp., Trichoderma sp., Fusarium equisetti, after seven days of incubation. The studies on fungi could be applied as suitable tools in biocontrol of nematode infections. However, additional surveys are required to select efficient with the ability to reduce the nematode larvae in the environment.

  8. Biological Control of the Nematode Infective larvae of Trichostrongylidae Family With Filamentous Fungi

    PubMed Central

    Zarrin, Majid; Rahdar, Mahmoud; Gholamian, Abbas

    2015-01-01

    Background: Biological control of parasitic nematodes by microorganisms is a promising approach to control such parasites. Microorganisms such as fungi, viruses and bacteria are recognized as biocontrol agents of nematodes. Objectives: The current study mainly aimed to evaluate the in vitro Potential of various saprophyte soil-fungi in reducing the infective larvae stage of parasitic nematode Trichostrongylidae family. Materials and Methods: Sheep feces were employed to provide the required third stage larvae source for the experiments. The nematode infective larvae of Trichostrongylidae family including three species of Ostertagia circumcincta, Marshalgia marshali and Heamonchos contortus were collected by Berman apparatus. Fifteen isolates of filamentous fungi were tested in the current study. One milliliter suspension containing 200 third stage larvae of Trichostrongylidae family was separately added to the fungal cultures in 2% water-agar medium Petri-dishes. Every day the live larvae were counted with light microscope (10X) and the number of captured larvae was recorded on different days. Results: Significant differences were observed in the results of co-culture of nematodes larva and fungi after seven days. The most effective fungi against the nematodes larvae were Cladosporium sp., Trichoderma sp., Fusarium equisetti, after seven days of incubation. Conclusions: The studies on fungi could be applied as suitable tools in biocontrol of nematode infections. However, additional surveys are required to select efficient with the ability to reduce the nematode larvae in the environment. PMID:25893084

  9. Transcriptomic responses of a simplified soil microcosm to a plant pathogen and its biocontrol agent reveal a complex reaction to harsh habitat.

    PubMed

    Perazzolli, Michele; Herrero, Noemí; Sterck, Lieven; Lenzi, Luisa; Pellegrini, Alberto; Puopolo, Gerardo; Van de Peer, Yves; Pertot, Ilaria

    2016-10-27

    Soil microorganisms are key determinants of soil fertility and plant health. Soil phytopathogenic fungi are one of the most important causes of crop losses worldwide. Microbial biocontrol agents have been extensively studied as alternatives for controlling phytopathogenic soil microorganisms, but molecular interactions between them have mainly been characterised in dual cultures, without taking into account the soil microbial community. We used an RNA sequencing approach to elucidate the molecular interplay of a soil microbial community in response to a plant pathogen and its biocontrol agent, in order to examine the molecular patterns activated by the microorganisms. A simplified soil microcosm containing 11 soil microorganisms was incubated with a plant root pathogen (Armillaria mellea) and its biocontrol agent (Trichoderma atroviride) for 24 h under controlled conditions. More than 46 million paired-end reads were obtained for each replicate and 28,309 differentially expressed genes were identified in total. Pathway analysis revealed complex adaptations of soil microorganisms to the harsh conditions of the soil matrix and to reciprocal microbial competition/cooperation relationships. Both the phytopathogen and its biocontrol agent were specifically recognised by the simplified soil microcosm: defence reaction mechanisms and neutral adaptation processes were activated in response to competitive (T. atroviride) or non-competitive (A. mellea) microorganisms, respectively. Moreover, activation of resistance mechanisms dominated in the simplified soil microcosm in the presence of both A. mellea and T. atroviride. Biocontrol processes of T. atroviride were already activated during incubation in the simplified soil microcosm, possibly to occupy niches in a competitive ecosystem, and they were not further enhanced by the introduction of A. mellea. This work represents an additional step towards understanding molecular interactions between plant pathogens and biocontrol

  10. Response to Thomas et al.: Biocontrol and indirect effects

    Treesearch

    Dean E. Pearson; Ragan M. Callaway

    2004-01-01

    In a recent TREE article [1], we identified three categories of unintended indirect effects that can arise from host-specific biological control agents: (i) ecological replacement; (ii) compensatory responses; and (iii) food-web interactions. Although our review focused on the biocontrol of plant pests, we suggested these concepts also apply to the biocontrol...

  11. Complete Genome Sequence of Biocontrol Strain Pseudomonas fluorescens LBUM223

    PubMed Central

    Roquigny, Roxane; Arseneault, Tanya; Gadkar, Vijay J.; Novinscak, Amy

    2015-01-01

    Pseudomonas fluorescens LBUM223 is a plant growth-promoting rhizobacterium (PGPR) with biocontrol activity against various plant pathogens. It produces the antimicrobial metabolite phenazine-1-carboxylic acid, which is involved in the biocontrol of Streptomyces scabies, the causal agent of common scab of potato. Here, we report the complete genome sequence of P. fluorescens LBUM223. PMID:25953163

  12. Recent taxonomy changes and their impact on biocontrol agents

    USDA-ARS?s Scientific Manuscript database

    The revolution in DNA sequencing technology has led to and improved understanding of genetics and taxonomy of biocontrol agents. Our lab recently reported the genomes of some important Bacillus bacterial biocontrol agents, which in turn resulted in a change of taxonomy for these commercially importa...

  13. Antifungal Substances from Streptomyces sp. A3265 Antagonistic to Plant Pathogenic Fungi

    PubMed Central

    Van Minh, Nguyen; Woo, E-Eum; Kim, Ji-Yul; Kim, Dae-Won; Hwang, Byung Soon; Lee, Yoon-Ju; Lee, In-Kyoung

    2015-01-01

    In a previous study, we identified a Streptomyces sp., A3265, as exhibiting potent antifungal activity against various plant pathogenic fungi, including Botrytis cinerea, Colletotrichum gloeosporioides, and Rhizoctonia solani. This strain also exhibited a biocontrolling effect against ginseng root rot and damping-off disease, common diseases of ginseng and other crops. In this study, we isolated two antifungal substances responsible for this biocontrolling effect via Diaion HP-20 and Sephadex LH-20 column chromatography, medium pressure liquid chromatography, and high-performance liquid chromatography. These compounds were identified as guanidylfungin A and methyl guanidylfungin A by spectroscopic methods. These compounds exhibited potent antimicrobial activity against various plant pathogenic fungi as well as against bacteria. PMID:26539051

  14. Prevalence of type III secretion system in effective biocontrol pseudomonads.

    PubMed

    Almario, Juliana; Gobbin, Davide; Défago, Geneviève; Moënne-Loccoz, Yvan; Rezzonico, Fabio

    2014-05-01

    Functional type III secretion system (T3SS) genes are needed for effective biocontrol of Pythium damping-off of cucumber by Pseudomonas fluorescens KD, but whether biocontrol Pseudomonas strains with T3SS genes display overall a higher plant-protecting activity is unknown. The assessment of 198 biocontrol fluorescent pseudomonads originating from 60 soils worldwide indicated that 32% harbour the ATPase-encoding T3SS gene hrcN, which was most often found in tomato isolates. The hrcN(+) biocontrol strains (and especially those also producing 2,4-diacetylphloroglucinol and displaying 1-aminocyclopropane-1-carboxylate deaminase activity) displayed higher plant-protecting ability in comparison with hrcN(-) biocontrol strains, both in the Pythium/cucumber and Fusarium/cucumber pathosystems. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  15. Pellet injector development and experiments at ORNL

    SciTech Connect

    Baylor, L.R.; Argo, B.E.; Barber, G.C.; Combs, S.K.; Cole, M.J.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Gouge, M.J.; Jernigan, T.C.; Langley, R.A.; Milora, S.L.; Qualls, A.L.; Schechter, D.E.; Sparks, D.O.; Tsai, C.C.; Wilgen, J.B.; Whealton, J.H.

    1993-11-01

    The development of pellet injectors for plasma fueling of magnetic confinement fusion experiments has been under way at Oak Ridge National Laboratory (ORNL) for the past 15 years. Recently, ORNL provided a tritium-compatible four-shot pneumatic injector for the Tokamak Fusion Test Reactor (TFTR) based on the in situ condensation technique that features three single-stage gas guns and an advanced two-stage light gas gun driver. In another application, ORNL supplied the Tore Supra tokamak with a centrifuge pellet injector in 1989 for pellet fueling experiments that has achieved record numbers of injected pellets into a discharge. Work is progressing on an upgrade to that injector to extend the number of pellets to 400 and improve pellet repeatability. In a new application, the ORNL three barrel repeating pneumatic injector has been returned from JET and is being readied for installation on the DIII-D device for fueling and enhanced plasma performance experiments. In addition to these experimental applications, ORNL is developing advanced injector technologies, including high-velocity pellet injectors, tritium pellet injectors, and long-pulse feed systems. The two-stage light gas gun and electron-beam-driven rocket are the acceleration techniques under investigation for achieving high velocity. A tritium proof-of-principle (TPOP) experiment has demonstrated the feasibility of tritium pellet production and acceleration. A new tritium-compatible, extruder-based, repeating pneumatic injector is being fabricated to replace the pipe gun in the TPOP experiment and will explore issues related to the extrudability of tritium and acceleration of large tritium pellets. The tritium pellet formation experiments and development of long-pulse pellet feed systems are especially relevant to the International Tokamak Engineering Reactor (ITER).

  16. Biocontrol potential of Halotolerant bacterial chitinase from high yielding novel Bacillus Pumilus MCB-7 autochthonous to mangrove ecosystem.

    PubMed

    Rishad, K S; Rebello, Sharrel; Shabanamol, P S; Jisha, M S

    2017-04-01

    The multifaceted role of chitinase in medicine, agriculture, environmental remediation and various other industries greatly demands the isolation of high yielding chitinase producing microorganisms with improved properties. The current study aimed to investigate the isolation, characterization and biocontrol prospective of chitinase producing bacterial strains autochthonous to the extreme conditions of mangrove ecosystems. Among the 51 bacterial isolates screened, Bacillus pumilus MCB-7 with highest chitinase production potential was identified and confirmed by 16S rDNA typing. Chitinase enzyme of MCB-7 was purified; the chitin degradation was evaluated by SEM and LC-MS. Unlike previously reported B.pumilus isolates, MCB-7 exhibited highest chitinase activity of 3.36U/mL, active even at high salt concentrations and temperature up to 60°C. The crude as well as purified enzyme showed significant antimycotic activity against agricultural pathogens such as Aspergillus flavus, Aspergillus niger, Aspergillus fumigatus, Ceratorhiza hydrophila and Fusarium oxysporum. The enzyme also exhibited biopesticidal role against larvae of Scirpophaga incertulas (Walker). [Lep.: Pyralidae], a serious agricultural pest of rice. The high chitinolytic and antimycotic potential of MCB-7 increases the prospects of the isolate as an excellent biocontrol agent. To the best of our knowledge, this is the first report of high chitinase yielding Bacillus pumilus strain from mangrove ecosystem with a biocontrol role against phytopathogenic fungi and insect larval pests. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Citrus compost and its water extract for cultivation of melon plants in greenhouse nurseries. Evaluation of nutriactive and biocontrol effects.

    PubMed

    Bernal-Vicente, A; Ros, M; Tittarelli, F; Intrigliolo, F; Pascual, J A

    2008-12-01

    Two different types of citrus composts, and their water extracts, were tested with regard to their utilisations as partial substitutes for peat in growing media for melon seedlings in greenhouse nurseries. Both compost showed higher plant growth than peat. Compost composed by citrus waste and green residue (C2) showed greater plant growth than compost obtained from the same organic matrices mentioned above further the addition of sludge obtained from citrus industry (C1). Compost C2 showed a greater auxinic effect than C1 and it was the only one that showed cytokinic effect. Both composts also demonstrated a biocontrol effect against Fusarium oxysporum for melon plants: the effects were also higher in C2 than in C1. Higher number of isolated fungi was active against F. oxysporum in compost C2, than compost C1. No different bacterial biocontrol efficacy was observed between both composts. The water extracts of both composts gave lower plant yields than their solid matrices, their relative effects being similar to those of the solid composts (C2 extract gave higher plant yields than the extract from C1). The biocontrol effects of compost water extracts followed the same trend.

  18. Comparative Genomic Analysis of Pseudomonas chlororaphis PCL1606 Reveals New Insight into Antifungal Compounds Involved in Biocontrol.

    PubMed

    Calderón, Claudia E; Ramos, Cayo; de Vicente, Antonio; Cazorla, Francisco M

    2015-03-01

    Pseudomonas chlororaphis PCL1606 is a rhizobacterium that has biocontrol activity against many soilborne phytopathogenic fungi. The whole genome sequence of this strain was obtained using the Illumina Hiseq 2000 sequencing platform and was assembled using SOAP denovo software. The resulting 6.66-Mb complete sequence of the PCL1606 genome was further analyzed. A comparative genomic analysis using 10 plant-associated strains within the fluorescent Pseudomonas group, including the complete genome of P. chlororaphis PCL1606, revealed a diverse spectrum of traits involved in multitrophic interactions with plants and microbes as well as biological control. Phylogenetic analysis of these strains using eight housekeeping genes clearly placed strain PCL1606 into the P. chlororaphis group. The genome sequence of P. chlororaphis PCL1606 revealed the presence of sequences that were homologous to biosynthetic genes for the antifungal compounds 2-hexyl, 5-propyl resorcinol (HPR), hydrogen cyanide, and pyrrolnitrin; this is the first report of pyrrolnitrin encoding genes in this P. chlororaphis strain. Single-, double-, and triple-insertional mutants in the biosynthetic genes of each antifungal compound were used to test their roles in the production of these antifungal compounds and in antagonism and biocontrol of two fungal pathogens. The results confirmed the function of HPR in the antagonistic phenotype and in the biocontrol activity of P. chlororaphis PCL1606.

  19. Impurity pellet injection experiments at TFTR

    SciTech Connect

    Marmar, E.S.

    1992-01-01

    Impurity (Li and C) pellet injection experiments on TFTR have produced a number of new and significant results. (1) We observe reproducible improvements of TFTR supershots after wall-conditioning by Li pellet injection ( lithiumization'). (2) We have made accurate measurements of the pitch angle profiles of the internal magnetic field using two novel techniques. The first measures the internal field pitch from the polarization angles of Li[sup +] line emission from the pellet ablation cloud, while the second measures the pitch angle profiles by observing the tilt of the cigar-shaped Li[sup +] emission region of the ablation cloud. (3) Extensive measurements of impurity pellet penetration into plasmas with central temperatures ranging from [approximately]0.3 to [approximately]7 keV have been made and compared with available theoretical models. Other aspects of pellet cloud physics have been investigated. (4) Using pellets as a well defined perturbation has allowed study of transport phenomena. In the case of small pellet perturbations, the characteristics of the background plasmas are probed, while with large pellets, pellet induced effects are clearly observed. These main results are discussed in more detail in this paper.

  20. 25 years of pelletizing at CVRD

    SciTech Connect

    Bandeira de Mello, L.A.; Mourao, J.M.; Cunha, J.M.; Piccolo, A.L.; Klein, M.S.

    1996-12-31

    This paper presents the evolution of the iron ore pelletizing activities at Companhia Vale do Rio Doce (CVRD), since the start-up of the first plant in the Tubarao area (Brazil), in 1969. The main features of CVRD`s pelletizing activities are described, focusing on the development of different types of pellets for the blast furnace and direct reduction markets, on the actions taken to face the urging necessity of cutting down energetic costs and on the handling of several different types of raw material. The profile of process control, quality management and environmental control at CVRD`s pelletizing plants is also presented.

  1. Current generation by phased injection of pellets

    SciTech Connect

    Fisch, N.J.

    1983-08-01

    By phasing the injection of frozen pellets into a tokamak plasma, it is possible to generate current. The current occurs when the electron flux to individual members of an array of pellets is asymmetric with respect to the magnetic field. The utility of this method for tokamak reactors, however, is unclear; the current, even though free in a pellet-fueled reactor, may not be large enough to be worth the trouble. Uncertainty as to the utility of this method is, in part, due to uncertainty as to proper modeling of the one-pellet problem.

  2. Phenotypic and genetic characterization of Paecilomyces lilacinus strains with biocontrol activity against root-knot nematodes.

    PubMed

    Gunasekera, T S; Holland, R J; Gillings, M R; Briscoe, D A; Neethling, D C; Williams, K L; Nevalainen, K M

    2000-09-01

    Efficient selection of fungi for biological control of nematodes requires a series of screening assays. Assessment of genetic diversity in the candidate species maximizes the variety of the isolates tested and permits the assignment of a particular genotype with high nematophagous potential using a rapid novel assay. Molecular analyses also facilitate separation between isolates, allowing the identification of proprietary strains and trace biocontrol strains in the environment. The resistance of propagules to UV radiation is an important factor in the survival of a biocontrol agent. We have analyzed 15 strains of the nematophagous fungus Paecilomyces lilacinus using these principles. Arbitrarily primed DNA and allozyme assays were applied to place the isolates into genetic clusters, and demonstrated that some genetically related P. lilacinus strains exhibit widespread geographic distributions. When exposed to UV radiation, some weakly nematophagous strains were generally more susceptible than effective isolates. A microtitre tray-based assay used to screen the pathogenic activity of each isolate to Meloidogyne javanica egg masses revealed that the nematophagous ability varied between 37%-100%. However, there was no clear relationship between nematophagous ability and genetic clusters. Molecular characterizations revealed sufficient diversity to allow tracking of strains released into the environment.

  3. Identification of a novel fungus, Trichoderma asperellum GDFS1009, and comprehensive evaluation of its biocontrol efficacy.

    PubMed

    Wu, Qiong; Sun, Ruiyan; Ni, Mi; Yu, Jia; Li, Yaqian; Yu, Chuanjin; Dou, Kai; Ren, Jianhong; Chen, Jie

    2017-01-01

    Due to its efficient broad-spectrum antimicrobial activity, Trichoderma has been established as an internationally recognized biocontrol fungus. In this study, we found and identified a novel strain of Trichoderma asperellum, named GDFS1009. The mycelium of T. asperellum GDFS1009 exhibits a high growth rate, high sporulation capacity, and strong inhibitory effects against pathogens that cause cucumber fusarium wilt and corn stalk rot. T. asperellum GDFS1009 secretes chitinase, glucanase, and protease, which can degrade the cell walls of fungi and contribute to mycoparasitism. The secreted xylanases are good candidates for inducing plant resistance and enhancing plant immunity against pathogens. RNA sequencing (RNA-seq) and gas chromatography-mass spectrometry (GC-MS) showed that T. asperellum GDFS1009 produces primary metabolites that are precursors of antimicrobial compounds; it also produces a variety of antimicrobial secondary metabolites, including polyketides and alkanes. In addition, this study speculated the presence of six antimicrobial peptides via ultra-performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC-QTOF-MS/MS). Future studies should focus on these antimicrobial metabolites for facilitating widespread application in the field of agricultural bio-control.

  4. Identification of a novel fungus, Trichoderma asperellum GDFS1009, and comprehensive evaluation of its biocontrol efficacy

    PubMed Central

    Wu, Qiong; Sun, Ruiyan; Ni, Mi; Yu, Jia; Li, Yaqian; Yu, Chuanjin; Dou, Kai; Ren, Jianhong; Chen, Jie

    2017-01-01

    Due to its efficient broad-spectrum antimicrobial activity, Trichoderma has been established as an internationally recognized biocontrol fungus. In this study, we found and identified a novel strain of Trichoderma asperellum, named GDFS1009. The mycelium of T. asperellum GDFS1009 exhibits a high growth rate, high sporulation capacity, and strong inhibitory effects against pathogens that cause cucumber fusarium wilt and corn stalk rot. T. asperellum GDFS1009 secretes chitinase, glucanase, and protease, which can degrade the cell walls of fungi and contribute to mycoparasitism. The secreted xylanases are good candidates for inducing plant resistance and enhancing plant immunity against pathogens. RNA sequencing (RNA-seq) and gas chromatography-mass spectrometry (GC-MS) showed that T. asperellum GDFS1009 produces primary metabolites that are precursors of antimicrobial compounds; it also produces a variety of antimicrobial secondary metabolites, including polyketides and alkanes. In addition, this study speculated the presence of six antimicrobial peptides via ultra-performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC-QTOF-MS/MS). Future studies should focus on these antimicrobial metabolites for facilitating widespread application in the field of agricultural bio-control. PMID:28644879

  5. Selection and evaluation of micro-organisms for biocontrol of Verticillium dahliae in olive.

    PubMed

    Varo, A; Raya-Ortega, M C; Trapero, A

    2016-09-01

    To identify potential biological control agents against Verticillium wilt in olive through a mass screening approach. A total of 47 strains and nine mixtures of micro-organisms were evaluated against Verticillium dahliae in a three stage screening: (i) in vitro, by the effect on the mycelial growth and spore germination of the pathogen; (ii) in natural infested soil, by the effect on the reduction of microsclerotia of the pathogen; (iii) in planta, by the effect on the infection of olive plants under controlled conditions. Various fungal and bacterial strains and mixtures inhibited the pathogen and showed consistent biocontrol activity against Verticillium wilt of olive. The screening has resulted in promising fungi and bacteria strains with antagonistic activity against Verticillium, such as two non-pathogenic Fusarium oxysporum, one Phoma sp., one Pseudomonas fluorescens and two mixtures of micro-organisms that may possess multiple modes of action. This study provides a practical basis for the potential use of selected strains as biocontrol agents for the protection of olive plants against V. dahliae infection. In addition, our study presented an effective method to evaluate antagonistic micro-organisms of V. dahliae in olive. © 2016 The Society for Applied Microbiology.

  6. Relationship between mycoparasites lifestyles and biocontrol behaviors against Fusarium spp. and mycotoxins production.

    PubMed

    Kim, Seon Hwa; Vujanovic, Vladimir

    2016-06-01

    Global food security research is seeking eco-friendly solutions to control mycotoxins in grain infected by fungi (molds). In particular, mycotoxigenic Fusarium spp. outbreak is a chronic threat for cereal grain production, human, and animal health. In this review paper, we discuss up-to-date biological control strategies in applying mycoparasites as biological control agents (BCA) to prevent plant diseases in crops and mycotoxins in grain, food, and feed. The aim is to increase food safety and to minimize economic losses due to the reduced grain yield and quality. However, recent papers indicate that the study of the BCA specialists with biotrophic lifestyle lags behind our understanding of the BCA generalists with necrotrophic lifestyle. We examine critical behavioral traits of the two BCA groups of mycoparasites. The goal is to highlight their major characteristics in the context of future research towards an efficient biocontrol strategy against mycotoxin-producing Fusarium species. The emphasis is put on biocontrol of Fusarium graminearum, F. avenaceum, and F. culmorum causing Fusarium head blight (FHB) in cereals and their mycotoxins.

  7. Genotypic and phenotypic differentiation of an antifungal biocontrol strain belonging to Bacillus subtilis.

    PubMed

    Marten, P; Smalla, K; Berg, G

    2000-09-01

    Physiological and molecular fingerprints of biotechnologically relevant rhizobacteria are necessary for registration, patenting, recognition and quality checking of the strains. To characterize the biological control agent, Bacillus subtilis B2g, the strain was compared with other plant-associated B. subtilis isolates. Phenotypic characterization included biochemical and nutritional properties, in vitro activity and analysis of potential antagonistic mechanisms towards several plant pathogenic fungi. According to the phenotypic characteristics, it was not possible to differentiate the biocontrol agent from the other strains, although the enzymatic fingerprint was unique. Genotypic diversity among the isolates was characterized by molecular fingerprinting methods using REP-PCR (repetitive extragenomic palindromic PCR), and macrorestriction of genomic DNA and electrophoretic separation of DNA fragments by pulsed-field gel electrophoresis (PFGE). A protocol for PFGE analysis using restriction enzyme SfiI for B. subtilis was developed. PFGE typing of B. subtilis B2g resulted in a unique fingerprint. Therefore, it was possible to differentiate B. subtilis B2g, the biocontrol agent of Phytovit, from other antifungal B. subtilis isolates.

  8. Micromorphology of pelletized soil conditioners

    NASA Astrophysics Data System (ADS)

    Hirsch, Florian; Dietrich, Nils; Knoop, Christine; Raab, Thomas

    2017-04-01

    Soil conditioners produced by anaerobic digestion and subsequent composting of organic household waste, bear the potential to improve unproductive farmland together with a reduced input risk of unwanted pollutants into the soils. Within the VeNGA project (http://www.biogas-network.de/venga), soil conditioners from anaerobically digested organic household waste are tested for their potential to increase plant growth in glasshouse and field experiments. Because the production techniques of these soil conditioners may influence their physical and chemical behaviour in the soil, two different techniques for pelletizing the soil conditioners where applied. We present findings from a pot experiment with cereal that has been sampled after two months for micromorphological analyses. We visualize the decomposition and the physical behaviour of the soil conditioners. Pellets produced in an agglomeration mixer result in dense balls, that are only slightly decomposed after the trial. But the soil conditioners created under pressure in a screw extruder are rich in voids and have the potential of retaining more soil water.

  9. Role of 2-hexyl, 5-propyl resorcinol production by Pseudomonas chlororaphis PCL1606 in the multitrophic interactions in the avocado rhizosphere during the biocontrol process.

    PubMed

    Calderón, Claudia E; de Vicente, Antonio; Cazorla, Francisco M

    2014-07-01

    Different bacterial traits can contribute to the biocontrol of soilborne phytopathogenic fungus. Among others, (1) antagonism, (2) competition for nutrients and niches, (3) induction of systemic resistance of the plants and (4) predation and parasitism are the most studied. Pseudomonas chlororaphis PCL1606 is an antagonistic rhizobacterium that produces the antifungal metabolite 2-hexyl, 5-propyl resorcinol (HPR). This bacterium can biologically control the avocado white root rot caused by Rosellinia necatrix. Confocal laser scanning microscopy of the avocado rhizosphere revealed that this biocontrol bacterium and the fungal pathogen compete for the same niche and presumably also for root exudate nutrients. The use of derivative mutants in the geners related to HPR biosynthesis (dar genes) revealed that the lack of HPR production by P. chlororaphis PCL1606 negatively influences the bacterial colonisation of the avocado root surface. Microscopical analysis showed that P. chlororaphis PCL1606 closely interacts and colonises the fungal hyphae, which may represent a novel biocontrol mechanism in this pseudomonad. Additionally, the presence of HPR-producing biocontrol bacteria negatively affects the ability of the fungi to infect the avocado root. HPR production negatively affects hyphal growth, leading to alterations in the R. necatrix physiology visible under microscopy, including the curling, vacuolisation and branching of hyphae, which presumably affects the colonisation and infection abilities of the fungus. This study provides the first report of multitrophic interactions in the avocado rhizosphere, advancing our understanding of the role of HPR production in those interactions.

  10. A Three-Way Transcriptomic Interaction Study of a Biocontrol Agent (Clonostachys rosea), a Fungal Pathogen (Helminthosporium solani), and a Potato Host (Solanum tuberosum).

    PubMed

    Lysøe, Erik; Dees, Merete W; Brurberg, May Bente

    2017-08-01

    Helminthosporium solani causes silver scurf, which affects the quality of potato. The biocontrol agent Clonostachys rosea greatly limited the severity of silver scurf symptoms and amount of H. solani genomic DNA in laboratory experiments. Transcriptomic analysis during interaction showed that H. solani gene expression was highly reduced when coinoculated with the biocontrol agent C. rosea, whereas gene expression of C. rosea was clearly boosted as a response to the pathogen. The most notable upregulated C. rosea genes were those encoding proteins involved in cellular response to oxidative stress, proteases, G-protein signaling, and the methyltransferase LaeA. The most notable potato response to both fungi was downregulation of defense-related genes and mitogen-activated protein kinase kinase kinases. At a later stage, this shifted, and most potato defense genes were turned on, especially those involved in terpenoid biosynthesis when H. solani was present. Some biocontrol-activated defense-related genes in potato were upregulated during early interaction with C. rosea alone that were not triggered by H. solani alone. Our results indicate that the reductions of silver scurf using C. rosea are probably due to a combination of mechanisms, including mycoparasitism, biocontrol-activated stimulation of plant defense mechanisms, microbial competition for nutrients, space, and antibiosis.

  11. Chemical ecology of fungi.

    PubMed

    Spiteller, Peter

    2015-07-01

    Fungi are widespread in nature and have conquered nearly every ecological niche. Fungi occur not only in terrestrial but also in freshwater and marine environments. Moreover, fungi are known as a rich source of secondary metabolites. Despite these facts, the ecological role of many of these metabolites is still unknown and the chemical ecology of fungi has not been investigated systematically so far. This review intends to present examples of the various chemical interactions of fungi with other fungi, plants, bacteria and animals and to give an overview of the current knowledge of fungal chemical ecology.

  12. Fungi associated with food and feed commodities from Ecuador.

    PubMed

    Pacin, A M; González, H H L; Etcheverry, M; Resnik, S L; Vivas, L; Espin, S

    2003-01-01

    Freshly harvested soybean, rice and corn from farms and corn-based pelleted feeds were collected from ranches from the coastal and mountain regions in Ecuador during 1998, and assessed for fungal contamination. The most prevalent fungi on pelleted feed were Aspergillus flavus and Fusarium graminearum. The prevalent fungi recovered from soybean were F. verticillioides, F. semitectum, Aspergillus flavus and A. ochraceus. In rice, F. oxysporum was the most prevalent toxigenic fungal species recorded, followed by F. verticillioides and A. flavus. In corn, F. verticillioides was the most prevalent fungus isolated in both the coastal and mountain regions, with high isolation frequencies of A. flavus and A. parasiticus at the coast. Based on the toxigenic species recovered, ochratoxin A may pose a contamination risk for soybean. A higher probability of aflatoxin contamination of corn was found in the coastal samples compared to those of the mountain region, while a risk of fumonisin contamination of corn exists in both regions.

  13. CHARACTERIZATION AND BIOCONTROL POTENT OF STREPTOMYCES SP. ISOLATED FROM THE RHIZOSPHERE OF ONONIS ANGUSTISSIMA LAM.

    PubMed

    Ghadbane, M; Belhadj, H; Medjekal, S; Harzallah, D

    2015-01-01

    A total of 40 actinomycetes isolated from rhizosphere soils of Ononis angustissima Lam. were in vitro tested for their antagonism against deferent pathogenic microorganisms by streak assay. Among the isolates, four (21, 2A26, 1B10 and 2C34) present a potent antagonism against both pathogenic bacteria and fungi, they were selected, identified by 16S rDNA sequence analysis and phenotypic properties, and tested for their antimicrobial activity as well as their biocontrol potential against Chickpea (Cicer arietinum L.) pathogenic fungus (Fusarium oxysporum). Cultural characteristic studies strongly suggested that these strains belong to the genus Streptomyces. The four Streptomyces sp., solubilize phosphate and produce extracellular fungal cell-wall degrading enzymes chitinase and protease, as well as a marked production of acid-β-indole acetic (AIA). The nucleotide sequence of the 16S rRNA gene of Streptomyces sp. strains 21, 2A26, 1B10 and 2C34 exhibited close similarity (62-75%) with Streptomyces parvulus MARS 16S rRNA genes. The inhibition was higher against fungi and Gram+ bacteria, while Gram- bacteria were less inhibited. The growth of the plant pathogenic fungus Fusarium oxysporum was considerably inhibited in the presence of the strains 21, 2A26, 1B10 and 2C34 culture supernatant. These studies revealed that the presence of the Streptomyces strains in the soil significantly promoted the growth of the Chickpea plants. These results indicate that the Streptomyces strains isolated for rhizosphere from Ononis angustissima Lam. growing in arid conditions in southern Algeria (Sahara) could be an interesting source for antimicrobial bioactive substances and as biocontrol agents.

  14. Looking West at Line Two Pelletizing Line, Centering Furnaces and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking West at Line Two Pelletizing Line, Centering Furnaces and Dewaxers of First Floor of Pellet Plant - Hematite Fuel Fabrication Facility, Pellet Plant, 3300 State Road P, Festus, Jefferson County, MO

  15. Estimating shot distance from limited pellets pattern.

    PubMed

    Plebe, Alessio; Compagnini, Domenico

    2012-10-10

    Several methods are available for shooting range estimation based on pellets pattern on the target that have a remarkable degree of accuracy. The task is usually approached working under the assumption that the entire distribution of pellets is available for examination. These methods fail, however, when the victim has been hit by a portion of the pattern only. The problem can be solved with reasonable accuracy when there are areas of void in the victim that are adjacent to the area struck by pellets. This study presents a method that can be used in precisely this type of situation, allowing the estimation of shot distance in cases of partial pellet patterns. It is based on collecting distributions in test shots at several distances, and taking samples in the targets, constrained by the shape of the void and the pellet hit areas. Statistical descriptors of patterns are extracted from such samples, and fed into a neural network classifier, estimating shot ranges of distance.

  16. Terpenoids from endophytic fungi.

    PubMed

    de Souza, Jucimar Jorgeane; Vieira, Ivo José Curcino; Rodrigues-Filho, Edson; Braz-Filho, Raimundo

    2011-12-19

    This work reviews the production of terpenoids by endophytic fungi and their biological activities, in period of 2006 to 2010. Sixty five sesquiterpenes, 45 diterpenes, five meroterpenes and 12 other terpenes, amounting to 127 terpenoids were isolated from endophytic fungi.

  17. Biocontrol: Bacillus penetrans and Related Parasites of Nematodes

    PubMed Central

    Sayre, R. M.

    1980-01-01

    Bacillus penetrans Mankau, 1975, previously described as Duboscqia penetrans Thorne 1940, is a candidate agent for biocontrol of nematodes. This review considers the life stages of this bacterium: vegetative growth phase, colony fragmentation, sporogenesis, soil phase, spore attachment, and penetration into larvae of root-knot nematodes. The morphology of the microthallus colonies and the unusual external features of the spore are discussed. Taxonomic affinities with the actinomycetes, particularly with the genus Pasteuria, are considered. Also discussed are other soil bacterial species that are potential biocontrol agents. Products of their bacterial fermentation in soil are toxic to nematodes, making them effective biocontrol agents. PMID:19300701

  18. Entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana reduce the survival of Xenopsylla brasiliensis larvae (Siphonaptera: Pulicidae).

    PubMed

    Mnyone, Ladslaus L; Ng'habi, Kija R; Mazigo, Humphrey D; Katakweba, Abdul A; Lyimo, Issa N

    2012-09-19

    Entomopathogenic fungi, particularly those belonging to the genera Metarhizium and Beauveria have shown great promise as arthropod vector control tools. These agents, however, have not been evaluated against flea vectors of plague. A 3-h exposure to the fungi coated paper at a concentration of 2 × 108 conidia m-2 infected >90% of flea larvae cadavers in the treatment groups. The infection reduced the survival of larvae that had been exposed to fungus relative to controls. The daily risk of dying was four- and over three-fold greater in larvae exposed to M. anisopliae (HR = 4, p<0.001) and B. bassiana (HR = 3.5, p<0.001) respectively. Both fungi can successfully infect and kill larvae of X. brasiliensis with a pooled median survival time (MST±SE) of 2 ± 0.31 days post-exposure. These findings justify further research to investigate the bio-control potential of entomopathogenic fungi against fleas.

  19. Bilateral shotgun pellet pulmonary emboli

    PubMed Central

    Huebner, Stephen; Ali, Sayed

    2012-01-01

    Intravascular migration of bullets and other foreign bodies is a rare but known complication of penetrating trauma. Missile embolization can represent a diagnostic challenge because it may present in various and unexpected ways. We present the case of a 54-year-old female who sustained shotgun pellet emboli to the pulmonary arteries following a left upper extremity gunshot wound and related vascular surgery. The case illustrates bilateral embolization, and the embolic events occurred following surgery. Embolization should be considered in evaluating patients with gunshot wounds, particularly if there are anomalous symptoms or the projectile is not found in the original, or expected, location. Close attention to the location of the foreign bodies on serial radiographs may reveal the diagnosis of intravascular embolization. PMID:22690290

  20. Looking Northeast Along Hallway between Pellet Plant and Oxide Building, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Northeast Along Hallway between Pellet Plant and Oxide Building, including Virgin Hopper Bins - Hematite Fuel Fabrication Facility, Pellet Plant, 3300 State Road P, Festus, Jefferson County, MO

  1. Parasitic weed management by using strigolactone-degrading fungi.

    PubMed

    Boari, Angela; Ciasca, Biancamaria; Pineda-Martos, Rocío; Lattanzio, Veronica Mt; Yoneyama, Koichi; Vurro, Maurizio

    2016-11-01

    Seed germination is a key phase of the parasitic plant life cycle that is stimulated by the secondary metabolites, mainly strigolactones (SLs), secreted by the host roots. Interventions during this stage would be particularly suitable for parasitic weed management practices, as blocking these chemical signals would prevent seed germination and thus parasite attack. Four fungal strains with different ecological functions were considered for their possible ability to metabolise SLs: Fusarium oxysporum and F. solani, biocontrol agents of Phelipanche ramosa; Trichoderma harzianum, a potential biopesticide; Botrytis cinerea, a phytopathogenic fungus. Four different SLs [the natural strigol, 5-deoxystrigol (5DS) and 4-deoxyorobanchol (4DO), and the synthetic analogue GR24] were added to fungal cultures, followed by determination of the SL content by liquid chromatography-tandem mass spectrometry. Differences were observed among microorganisms, treatments and SLs used. T. harzianum and F. oxysporum were the most capable of reducing the SL content; considering the whole set of fungi used, 5DS and 4DO proved to be the most degradable SLs. Beneficial microscopic fungi could differently be used for biocontrolling parasitic weeds, acting as a 'physiological' barrier, by preventing the germination of their seeds through the ability to biotransform the stimulatory signals. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  2. Biocontrol interventions for inactivation of foodborne pathogens on produce

    USDA-ARS?s Scientific Manuscript database

    Post-harvest interventions for control of foodborne pathogens on minimally processed foods are crucial for food safety. Biocontrol interventions have the primary objective of developing novel antagonists in combinations with physical and chemical interventions to inactivate pathogenic microbes. Ther...

  3. Pelletization of fine coals. Final report

    SciTech Connect

    Sastry, K.V.S.

    1995-12-31

    Coal is one of the most abundant energy resources in the US with nearly 800 million tons of it being mined annually. Process and environmental demands for low-ash, low-sulfur coals and economic constraints for high productivity are leading the coal industry to use such modern mining methods as longwall mining and such newer coal processing techniques as froth flotation, oil agglomeration, chemical cleaning and synthetic fuel production. All these processes are faced with one common problem area--fine coals. Dealing effectively with these fine coals during handling, storage, transportation, and/or processing continues to be a challenge facing the industry. Agglomeration by the unit operation of pelletization consists of tumbling moist fines in drums or discs. Past experimental work and limited commercial practice have shown that pelletization can alleviate the problems associated with fine coals. However, it was recognized that there exists a serious need for delineating the fundamental principles of fine coal pelletization. Accordingly, a research program has been carried involving four specific topics: (i) experimental investigation of coal pelletization kinetics, (ii) understanding the surface principles of coal pelletization, (iii) modeling of coal pelletization processes, and (iv) simulation of fine coal pelletization circuits. This report summarizes the major findings and provides relevant details of the research effort.

  4. A centrifuge CO2 pellet cleaning system

    NASA Astrophysics Data System (ADS)

    Foster, C. A.; Fisher, P. W.; Nelson, W. D.; Schechter, D. E.

    1995-03-01

    An advanced turbine/CO2 pellet accelerator is being evaluated as a depaint technology at Oak Ridge National Laboratory (ORNL). The program, sponsored by Warner Robins Air Logistics Center (ALC), Robins Air Force Base, Georgia, has developed a robot-compatible apparatus that efficiently accelerates pellets of dry ice with a high-speed rotating wheel. In comparison to the more conventional compressed air 'sandblast' pellet accelerators, the turbine system can achieve higher pellet speeds, has precise speed control, and is more than ten times as efficient. A preliminary study of the apparatus as a depaint technology has been undertaken. Depaint rates of military epoxy/urethane paint systems on 2024 and 7075 aluminum panels as a function of pellet speed and throughput have been measured. In addition, methods of enhancing the strip rate by combining infra-red heat lamps with pellet blasting and by combining the use of environmentally benign solvents with the pellet blasting have also been studied. The design and operation of the apparatus will be discussed along with data obtained from the depaint studies.

  5. A centrifuge CO2 pellet cleaning system

    NASA Technical Reports Server (NTRS)

    Foster, C. A.; Fisher, P. W.; Nelson, W. D.; Schechter, D. E.

    1995-01-01

    An advanced turbine/CO2 pellet accelerator is being evaluated as a depaint technology at Oak Ridge National Laboratory (ORNL). The program, sponsored by Warner Robins Air Logistics Center (ALC), Robins Air Force Base, Georgia, has developed a robot-compatible apparatus that efficiently accelerates pellets of dry ice with a high-speed rotating wheel. In comparison to the more conventional compressed air 'sandblast' pellet accelerators, the turbine system can achieve higher pellet speeds, has precise speed control, and is more than ten times as efficient. A preliminary study of the apparatus as a depaint technology has been undertaken. Depaint rates of military epoxy/urethane paint systems on 2024 and 7075 aluminum panels as a function of pellet speed and throughput have been measured. In addition, methods of enhancing the strip rate by combining infra-red heat lamps with pellet blasting and by combining the use of environmentally benign solvents with the pellet blasting have also been studied. The design and operation of the apparatus will be discussed along with data obtained from the depaint studies.

  6. A Review of Pellets from Different Sources

    PubMed Central

    Miranda, Teresa; Montero, Irene; Sepúlveda, Francisco José; Arranz, José Ignacio; Rojas, Carmen Victoria; Nogales, Sergio

    2015-01-01

    The rise in pellet consumption has resulted in a wider variety of materials for pellet manufacture. Thus, pellet industry has started looking for alternative products, such as wastes from agricultural activities, forestry and related industries, along with the combination thereof, obtaining a broad range of these products. In addition, the entry into force of EN ISO 17225 standard makes wood pellet market (among other types) possible for industry and household purposes. Therefore, wastes that are suitable for biomass use have recently increased. In this study, the main characteristics of ten kinds of laboratory-made pellets from different raw materials were analyzed. Thus, we have focused on the most limiting factors of quality standards that determine the suitability for biomass market, depending on the kind of pellet. The results showed considerable differences among the analyzed pellets, exceeding the limits established by the standard in almost all cases, especially concerning ash content and N and S composition. The requirements of the studied standard, very demanding for certain factors, disable the entry of these densified wastes in greater added value markets. PMID:28788009

  7. A Review of Pellets from Different Sources.

    PubMed

    Miranda, Teresa; Montero, Irene; Sepúlveda, Francisco José; Arranz, José Ignacio; Rojas, Carmen Victoria; Nogales, Sergio

    2015-03-27

    The rise in pellet consumption has resulted in a wider variety of materials for pellet manufacture. Thus, pellet industry has started looking for alternative products, such as wastes from agricultural activities, forestry and related industries, along with the combination thereof, obtaining a broad range of these products. In addition, the entry into force of EN ISO 17225 standard makes wood pellet market (among other types) possible for industry and household purposes. Therefore, wastes that are suitable for biomass use have recently increased. In this study, the main characteristics of ten kinds of laboratory-made pellets from different raw materials were analyzed. Thus, we have focused on the most limiting factors of quality standards that determine the suitability for biomass market, depending on the kind of pellet. The results showed considerable differences among the analyzed pellets, exceeding the limits established by the standard in almost all cases, especially concerning ash content and N and S composition. The requirements of the studied standard, very demanding for certain factors, disable the entry of these densified wastes in greater added value markets.

  8. Microbiological survey of birds of prey pellets.

    PubMed

    Dipineto, Ludovico; Bossa, Luigi Maria De Luca; Pace, Antonino; Russo, Tamara Pasqualina; Gargiulo, Antonio; Ciccarelli, Francesca; Raia, Pasquale; Caputo, Vincenzo; Fioretti, Alessandro

    2015-08-01

    A microbiological survey of 73 pellets collected from different birds of prey species housed at the Wildlife Rescue and Rehabilitation Center of Napoli (southern Italy) was performed. Pellets were analyzed by culture and biochemical methods as well as by serotyping and polymerase chain reaction. We isolated a wide range of bacteria some of them also pathogens for humans (i.e. Salmonella enterica serotype Typhimurium, Campylobacter coli, Escherichia coli O serogroups). This study highlights the potential role of birds of prey as asymptomatic carriers of pathogenic bacteria which could be disseminated in the environment not only through the birds of prey feces but also through their pellets.

  9. Bacteriophages as biocontrol agents in food.

    PubMed

    Hudson, J A; Billington, C; Carey-Smith, G; Greening, G

    2005-02-01

    Bacteriophages possess attributes that appear to be attractive to those searching for novel ways to control foodborne pathogens and spoilage organisms. These phages have a history of safe use, can be highly host specific, and replicate in the presence of a host. Campylobacter, Salmonella, and Listeria monocytogenes and various spoilage organisms have responded to phage control on some foods. However, the use of phages as biocontrol agents is complicated by factors such as an apparent requirement for a threshold level of host before replication can proceed and by suboptimal performance, at best, at temperatures beneath the optimum for the host. This review is a summary of the information on these issues and includes brief descriptions of alternative phage-based strategies for control of foodborne pathogens.

  10. Predacious bacteria, Bdellovibrio with potential for biocontrol.

    PubMed

    Markelova, Natalia Y

    2010-11-01

    Bacteria of the genus of Bdellovibrio are highly motile Gram-negative predators of other Gram-negative bacteria causing lysis of their prey. Here we report results of studies on the interactions of Bdellovibrio with species of Alcaligenes, Campylobacter, Erwinia, Escherichia, Helicobacter, Pseudomonas, Legionella, and Shigella in agar lower, liquid media and cells attached to a surface. Helicobacter pylori was studied employing both actively growing and viable but nonculturable (VBNC) cells. The majority of the bacterial strains tested were found to be susceptible to Bdellovibrio. A significant observation was that Bdellovibrio attacked both actively growing and VBNC H. pylori, that phenomenon has never been reported. The results indicate that bdellovibrios have potential as biocontrol agents.

  11. Protozoa Drive the Dynamics of Culturable Biocontrol Bacterial Communities.

    PubMed

    Müller, Maren Stella; Scheu, Stefan; Jousset, Alexandre

    2013-01-01

    Some soil bacteria protect plants against soil-borne diseases by producing toxic secondary metabolites. Such beneficial biocontrol bacteria can be used in agricultural systems as alternative to agrochemicals. The broad spectrum toxins responsible for plant protection also inhibit predation by protozoa and nematodes, the main consumers of bacteria in soil. Therefore, predation pressure may favour biocontrol bacteria and contribute to plant health. We analyzed the effect of Acanthamoeba castellanii on semi-natural soil bacterial communities in a microcosm experiment. We determined the frequency of culturable bacteria carrying genes responsible for the production of the antifungal compounds 2,4-diacetylphloroglucinol (DAPG), pyrrolnitrin (PRN) and hydrogen cyanide (HCN) in presence and absence of A. castellanii. We then measured if amoebae affected soil suppressiveness in a bioassay with sugar beet seedlings confronted to the fungal pathogen Rhizoctonia solani. Amoebae increased the frequency of both DAPG and HCN positive bacteria in later plant growth phases (2 and 3 weeks), as well as the average number of biocontrol genes per bacterium. The abundance of DAPG positive bacteria correlated with disease suppression, suggesting that their promotion by amoebae may enhance soil health. However, the net effect of amoebae on soil suppressiveness was neutral to slightly negative, possibly because amoebae slow down the establishment of biocontrol bacteria on the recently emerged seedlings used in the assay. The results indicate that microfaunal predators foster biocontrol bacterial communities. Understanding interactions between biocontrol bacteria and their predators may thus help developing environmentally friendly management practices of agricultural systems.

  12. Protozoa Drive the Dynamics of Culturable Biocontrol Bacterial Communities

    PubMed Central

    Müller, Maren Stella; Scheu, Stefan; Jousset, Alexandre

    2013-01-01

    Some soil bacteria protect plants against soil-borne diseases by producing toxic secondary metabolites. Such beneficial biocontrol bacteria can be used in agricultural systems as alternative to agrochemicals. The broad spectrum toxins responsible for plant protection also inhibit predation by protozoa and nematodes, the main consumers of bacteria in soil. Therefore, predation pressure may favour biocontrol bacteria and contribute to plant health. We analyzed the effect of Acanthamoeba castellanii on semi-natural soil bacterial communities in a microcosm experiment. We determined the frequency of culturable bacteria carrying genes responsible for the production of the antifungal compounds 2,4-diacetylphloroglucinol (DAPG), pyrrolnitrin (PRN) and hydrogen cyanide (HCN) in presence and absence of A. castellanii. We then measured if amoebae affected soil suppressiveness in a bioassay with sugar beet seedlings confronted to the fungal pathogen Rhizoctonia solani. Amoebae increased the frequency of both DAPG and HCN positive bacteria in later plant growth phases (2 and 3 weeks), as well as the average number of biocontrol genes per bacterium. The abundance of DAPG positive bacteria correlated with disease suppression, suggesting that their promotion by amoebae may enhance soil health. However, the net effect of amoebae on soil suppressiveness was neutral to slightly negative, possibly because amoebae slow down the establishment of biocontrol bacteria on the recently emerged seedlings used in the assay. The results indicate that microfaunal predators foster biocontrol bacterial communities. Understanding interactions between biocontrol bacteria and their predators may thus help developing environmentally friendly management practices of agricultural systems. PMID:23840423

  13. The Ignitor Fast Pellet Injector

    NASA Astrophysics Data System (ADS)

    Frattolillo, A.; Migliori, S.; Bombarda, F.; Milora, S. L.; Baylor, L. R.; Combs, S. K.

    2004-11-01

    A collaboration between the ENEA Laboratory at Frascati and the Fusion Technology Group of Oak Ridge for the development of a fast pellet injector for the Ignitor ignition experiment has been established. The program aims at the construction of a 4 barrel, double stage gun able to reach speeds up to 4 km/s and thus penetrate to the core of the plasma column. The compact size of the Ignitor machine favors the injection from the low field side, for which very positive results have been obtained on the FTU machine [1], in terms of density profile peaking and good energy confinement. The ongoing activities include the procurement of all the hardware for the criocooler, diagnostics and control electronics, from the ORNL side, and the design and construction of the gun by ENEA. A new fast valve has been developed that considerably reduces the requirements on the expansion volumes necessary to prevent the propulsion gas to reach the plasma chamber. [1] D. Frigione, et al., Nuclear Fusion 41, 1613 (2001).

  14. Hydrogen Uptake of DPB Getter Pellets

    SciTech Connect

    Dinh, L N; Schildbach, M A; Herberg, J L; Saab, A P; Weigle, J; Chinn, S C; Maxwell, R S; McLean II, W

    2008-05-30

    The physical and chemical properties of 1,4-diphenylbutadiyne (DPB) blended with carbon-supported Pd (DPB-Pd/C) in the form of pellets during hydrogenation were investigated. A thermogravimetric analyzer (TGA) was employed to measure the kinetics of the hydrogen uptake by the DPB getter pellets. The kinetics obtained were then used to develop a semi-empirical model, based on gas diffusion into solids, to predict the performance of the getter pellets under various conditions. The accuracy of the prediction model was established by comparing the prediction models with independent experimental data on hydrogen pressure buildup in sealed systems containing DPB getter pellets and subjected to known rates of hydrogen input. The volatility of the hydrogenated DPB products and its effects on the hydrogen uptake kinetics were also analyzed.

  15. Plasma gun pellet acceleration modeling and experiment

    SciTech Connect

    Kincaid, R.W.; Bourham, M.A.; Gilligan, J.G.

    1996-12-31

    Modifications to the electrothermal plasma gun SIRENS have been completed to allow for acceleration experiments using plastic pellets. Modifications have been implemented to the 1-D, time dependent code ODIN to include pellet friction, momentum, and kinetic energy with options of variable barrel length. The code results in the new version, POSEIDON, compare favorably with experimental data and with code results from ODIN. Predicted values show an increased pellet velocity along the barrel length, achieving 2 km/s exit velocity. Measured velocity, at three locations along the barrel length, showed good correlation with predicted values. The code has also been used to investigate the effectiveness of longer pulse length on pellet velocity using simulated ramp up and down currents with flat top, and triangular current pulses with early and late peaking. 16 refs., 5 figs.

  16. Modeling of a Hydrogenic Pellet Production System

    NASA Astrophysics Data System (ADS)

    Leachman, J. W.; Pfotenhauer, J. M.; Nellis, G. F.

    2010-04-01

    Solid hydrogenic pellets are used as fuel for fusion energy machines like the ITER device. This paper discusses the numerical modeling of a Pellet Production System (PPS) that is used to generate these pellets. The PPS utilizes a source of supercritical helium to provide the cooling that is necessary to precool, liquefy, and solidify hydrogenic material that is ultimately extruded and cut into fuel pellets. The specific components within the PPS include a pre-cooling heat exchanger, a liquefier, and a twin-screw solidifying extruder. This paper presents numerical models of each component. These numerical models are used as design tools to predict the performance of the respective devices. The performance of the PPS is dominated by the heat transfer coefficient and viscous dissipation associated with the solidifying hydrogenic fluid in the twin-screw extruder. This observation motivates experimental efforts aimed at precise measurement of these quantities.

  17. Tritium recovery from lithium oxide pellets

    SciTech Connect

    Bertone, P.C.; Jassby, D.L.

    1984-01-01

    The TFTR Lithium Blanket Module is an assembly containing 650 kg of lithium oxide that will be used to test the ability of neutronics codes to model the tritium breeding characteristics of limited-coverage breeding zones in a tokamak. It is required that tritium concentrations as low as 0.1 nCi/g bred in both metallic lithium samples and lithium oxide pellets be measured with an uncertainty not exceeding +- 6%. A tritium assay technique for the metallic samples which meets this criterion has been developed. Two assay techniques for the lithium oxide pellets are being investigated. In one, the pellets are heated in a flowing stream of hydrogen, while in the other, the pellets are dissolved in 12 M hydrochloric acid.

  18. Numerical studies of biocontrol efficacies of foliar plant pathogens in relation to the characteristics of a biocontrol agent.

    PubMed

    Xu, X-M; Salama, N; Jeffries, P; Jeger, M J

    2010-08-01

    A previously published generic mathematic model has been used in a numerical study to understand the dynamics of foliar pathogens in relation to mechanisms, and timing and coverage of biocontrol agent (BCA) applications. With the model parameter values used, it was demonstrated that a BCA possessing either competition or induced resistance as the main mechanism of biological control was more effective in reducing disease development than a BCA with either mycoparasitism or antibiosis as its mechanism. Application coverage, ranging from 50 to 90%, had little effect on biocontrol efficacy, particularly for a BCA with competition and induced resistance as the main mechanism of biocontrol. Conversely, delayed application of BCA had more profound effects on biocontrol efficacy for those with competition or induced resistance as their main mechanism than those with mycoparasitism and antibiosis. Biocontrol efficacy was greatest for a single BCA combining competition with mycoparasitism or antibiosis. The efficacy for a single BCA combining induced resistance with competition critically depended on application time; the efficacy was greatly reduced for delayed applications. The present study suggests that development of an effective strategy for BCA application is critically dependent upon our quantitative understanding of several key biocontrol processes and their interactions. Without reliable quantitative estimation of these processes, it is impossible to make quantitative predictions about biological control and hence to optimize BCA application strategies.

  19. Tailoring biocontrol to maximize top-down effects: on the importance of underlying site fertility.

    PubMed

    Hovick, Stephen M; Carson, Walter P

    2015-01-01

    The degree to which biocontrol agents impact invasive plants varies widely across landscapes, often for unknown reasons. Understanding this variability can help optimize invasive species management while also informing our understanding of trophic linkages. To address these issues, we tested three hypotheses with contrasting predictions regarding the likelihood of biocontrol success. (1) The biocontrol effort hypothesis: invasive populations are regulated primarily by top-down effects, predicting that increased biocontrol efforts alone (e.g., more individuals of a given biocontrol agent or more time since agent release) will enhance biocontrol success. (2) The relative fertility hypothesis: invasive populations are regulated primarily by bottom-up effects, predicting that nutrient enrichment will increase dominance by invasives and thus reduce biocontrol success, regardless of biocontrol efforts. (3) The fertility-dependent biocontrol effort hypothesis: top-down effects will only regulate invasive populations if bottom-up effects are weak. It predicts that greater biocontrol efforts will increase biocontrol success, but only in low-nutrient sites. To test these hypotheses, we surveyed 46 sites across three states with prior releases of Galerucella beetles, the most common biocontrol agents used against invasive purple loosestrife (Lythrum salicaria). We found strong support for the fertility-dependent biocontrol effort hypothesis, as biocontrol success occurred most often with greater biocontrol efforts, but only in low-fertility sites. This result held for early stage metrics of biocontrol success (higher Galerucella abundance) and ultimate biocontrol outcomes (decreased loosestrife plant size and abundance). Presence of the invasive grass Phalaris arundinacea was also inversely related to loosestrife abundance, suggesting that biocontrol-based reductions in loosestrife made secondary invasion by P. arundinacea more likely. Our data suggest that low-nutrient sites

  20. The effect of polycarbophil on the gastric emptying of pellets.

    PubMed

    Khosla, R; Davis, S S

    1987-01-01

    The influence of the putative bioadhesive, polycarbophil, on the gastric emptying of a pellet formulation, has been investigated in three fasted subjects. The pellets were radiolabelled with technetium-99m. Gastric emptying was measured using the technique of gamma scintigraphy. The pellets emptied from the stomach rapidly and in an exponential manner. Polycarbophil did not retard the gastric emptying of the pellets.

  1. Ciliates expel environmental Legionella-laden pellets to stockpile food.

    PubMed

    Hojo, Fuhito; Sato, Daisuke; Matsuo, Junji; Miyake, Masaki; Nakamura, Shinji; Kunichika, Miyuki; Hayashi, Yasuhiro; Yoshida, Mitsutaka; Takahashi, Kaori; Takemura, Hiromu; Kamiya, Shigeru; Yamaguchi, Hiroyuki

    2012-08-01

    When Tetrahymena ciliates are cultured with Legionella pneumophila, the ciliates expel bacteria packaged in free spherical pellets. Why the ciliates expel these pellets remains unclear. Hence, we determined the optimal conditions for pellet expulsion and assessed whether pellet expulsion contributes to the maintenance of growth and the survival of ciliates. When incubated with environmental L. pneumophila, the ciliates expelled the pellets maximally at 2 days after infection. Heat-killed bacteria failed to produce pellets from ciliates, and there was no obvious difference in pellet production among the ciliates or bacterial strains. Morphological studies assessing lipid accumulation showed that pellets contained tightly packed bacteria with rapid lipid accumulation and were composed of the layers of membranes; bacterial culturability in the pellets rapidly decreased, in contrast to what was seen in ciliate-free culture, although the bacteria maintained membrane integrity in the pellets. Furthermore, ciliates newly cultured with pellets were maintained and grew vigorously compared with those without pellets. In contrast, a human L. pneumophila isolate killed ciliates 7 days postinfection in a Dot/Icm-dependent manner, and pellets harboring this strain did not support ciliate growth. Also, pellets harboring the human isolate were resuscitated by coculturing with amoebae, depending on Dot/Icm expression. Thus, while ciliates expel pellet-packaged environmental L. pneumophila for stockpiling food, the pellets packaging the human isolate are harmful to ciliate survival, which may be of clinical significance.

  2. Comparative Properties of Bamboo and Rice Straw Pellets

    Treesearch

    Xianmiao Liu; Zhijia Liu; Benhua Fei; Zhiyong Cai; Zehui Jiang; Xing' e Liu

    2013-01-01

    Bamboo is a potential major bio-energy resource. Tests were carried out to compare and evaluate the property of bamboo and rice straw pellets, rice straw being the other main source of biomass solid fuel in China. All physical properties of untreated bamboo pellets (UBP), untreated rice straw pellets (URP), carbonized bamboo pellets (CBP), and carbonized rice straw...

  3. Apparatus for feeding nuclear fuel pellets to a loading tray

    SciTech Connect

    Huggins, T.B.

    1981-12-08

    Apparatus for feeding nuclear fuel pellets at a uniform, predetermined rate between pellet centering and grinding apparatus and a tray used for loading pellets into a nuclear fuel rod are described. Pellets discharged from the grinder are conveyed by a woven wire belt to a drive wheel which develops a force available to be applied to pellets preceding it on the belt. The pellets pass under the drive wheel which adds additional weight acting vertically on each pellet. This total weight of pellet and drive wheel coupled with wire belt linear movement acts to push a line of about 36 pellets onto a pellet dumping mechanism. As the dumping mechanism is actuated to dump the pellets on to a loading tray, the pellets moving toward the mechanism are clamped in a stationary position and the drive wheel simultaneously is lifted from its pellet contacting position until the pellet dumping process is completed. The clamping device is then lifted from its pellet and the drive wheel simultaneously is lowered into a pellet contacting position.

  4. Trichoderma virens as a biocontrol of Toxocara canis: In vivo evaluation.

    PubMed

    de Souza Maia Filho, Fernando; da Silva Fonseca, Anelise Oliveira; Persici, Beatriz Maroneze; de Souza Silveira, Julia; Braga, Caroline Quintana; Pötter, Luciana; de Avila Botton, Sônia; Brayer Pereira, Daniela Isabel

    Microorganisms have been widely studied as biological control agents of parasites of medical and veterinary importance. Coprophagous arthropods, bacteria and fungi are among the different organisms evaluated as potential biological control agents. Nematophagous fungi capture and digest the free forms of nematodes in the soil. Due to its zoonotic potential, Toxocara canis have been brought to the attention of researchers. The aim of the present study was to determine whether the administration of embryonated T. canis eggs exposed to the nematophagous fungus Trichoderma virens reduces parasite infection in experimental animals. Embryonated T. canis eggs were exposed to T. virens mycelium for 15 days at 25°C. Subsequently, 100 fungus-exposed eggs were orally administered to 20 Swiss mice. As a positive control, another 20 mice received 100 embryonated eggs that were not exposed to the fungus. After 48h, the animals were killed, and heart, lungs and liver were harvested for the recovery of larvae. The organs of the animals that received embryonated T. canis eggs exposed to the fungus showed a lower mean larval recovery when compared with the animals that received embryonated eggs without fungus exposure (p<0.05). The exposure of T. canis eggs to T. virens reduces the experimental infection, demonstrating the potential of this nematophagous fungus as a biocontrol agent. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Synthesis of biocontrol macromolecules by derivative of chitosan with surfactin and antifungal evaluation.

    PubMed

    Yuan, Bo; Xu, Pei-Yuan; Zhang, Yue-Ji; Wang, Pei-Pei; Yu, Hong; Jiang, Ji-Hong

    2014-05-01

    A derivative of chitosan was prepared with chitosan and β-cyclodextrins, which was synthesized by the immobilization reaction, as a carrier to adsorb surfactin produced from Bacillus amyloliquefaciens and got biological macromolecules. The antifungal activity against three sapstain fungi by a combination of macromolecules was tested. The results showed that the macromolecules inhibited the mycelium growth of sapstain fungi Lasiodiplodia rubropurpurea, L. crassispora, and L. theobromae by about 73.22%, 76.72%, and 70.22%, respectively. The macromolecules were relatively thermally stable with more than 50% of the antifungal activity even after being held at 121°C for 30 min. Meanwhile, the activity of the macromolecules remained more than 55% at a pH value ranging from 4 to 12. The macromolecules were resistant to hydrolysis by most protein-denaturing detergents and other enzymes. The results indicated the macromolecules might provide an alternative bioresource for the bio-control of sapstain. Copyright © 2014. Published by Elsevier B.V.

  6. Pelletization process of postproduction plant waste

    NASA Astrophysics Data System (ADS)

    Obidziński, S.

    2012-07-01

    The results of investigations on the influence of material, process, and construction parameters on the densification process and density of pellets received from different mixtures of tobacco and fine-grained waste of lemon balm are presented. The conducted research makes it possible to conclude that postproduction waste eg tobacco and lemon balm wastes can be successfully pelletized and used as an ecological, solid fuels.

  7. Single pellet crush strength testing of catalysts

    SciTech Connect

    Brienza, P.K. )

    1988-09-01

    ASTM D-32 Committee on Catalysts has developed a standard test method for single pellet crush strength for formed catalyst shapes. This standard was issued under the fixed designation D 4179. The method is applicable to regular catalyst shapes such as tablets and spheres. Extrudates, granular materials, and other irregular shapes are excluded. The committee continues to work on the development of a method for the single pellet crush testing of extrudates.

  8. An economical and market analysis of Canadian wood pellets.

    SciTech Connect

    Peng, J.

    2010-08-01

    This study systematically examined the current and future wood pellet market, estimated the cost of Canadian torrefied pellets, and compared the torrefied pellets with the conventional pellets based on literature and industrial data. The results showed that the wood pellet industry has been gaining significant momentum due to the European bioenergy incentives and the rising oil and natural gas prices. With the new bioenergy incentives in USA, the future pellets market may shift to North America, and Canada can potentially become the largest pellet production centre, supported by the abundant wood residues and mountain pine beetle (MPB) infested trees.

  9. Gas adsorption capacity of wood pellets

    DOE PAGES

    Yazdanpanah, F.; Sokhansanj, Shahabaddine; Lim, C. Jim; ...

    2016-02-03

    In this paper, temperature-programmed desorption (TPD) analysis was used to measure and analyze the adsorption of off-gases and oxygen by wood pellets during storage. Such information on how these gases interact with the material helps in the understanding of the purging/stripping behavior of off-gases to develop effective ventilation strategies for wood pellets. Steam-exploded pellets showed the lowest carbon dioxide (CO2) uptake compared to the regular and torrefied pellets. The high CO2 adsorption capacity of the torrefied pellets could be attributed to their porous structure and therefore greater available surface area. Quantifying the uptake of carbon monoxide by pellets was challengingmore » due to chemical adsorption, which formed a strong bond between the material and carbon monoxide. The estimated energy of desorption for CO (97.8 kJ/mol) was very high relative to that for CO2 (7.24 kJ/mol), demonstrating the mechanism of chemical adsorption and physical adsorption for CO and CO2, respectively. As for oxygen, the strong bonds that formed between the material and oxygen verified the existence of chemical adsorption and formation of an intermediate material.« less

  10. [Pellet guns: a persistent threat to eyes].

    PubMed

    Assaf, E; Emadisson, H; Bendeddouche, K; Forestier, F; Salvanet-Bouccara, A

    2003-11-01

    Following a recent case of bilateral perforating ocular trauma by multiple pellets, the authors reviewed pellet traumatisms treated in the Emergency Department and operated on in the Ophthalmology Department of the Villeneuve-St-Georges Hospital over the past 15 years. At close range, pellet weapon shootings can generate lid, conjunctiva, and powder cornea tattoos; in these cases, the lesions are often unilateral. Shooting at longer range does not result in corneodermic tattoos, but because pellets scatter, binocular lesions frequently occur. The different lesions caused by these nonmagnetic foreign bodies are often very serious. An early, even very early, traumatic cataract is sometimes very difficult to treat in these polytraumatized eyes. The visual prognosis is more reserved, as the impact zones often involve the posterior pole and the macular area. The best recovered visual acuity is 30-35/20, with visual field alterations, but the injury to the eyeball by multiple pellets can generate globe atrophy. The authors stress the gravity of these ocular traumas, fortunately rarer but not completely eradicated since the law of May 6, 1995, which restricted the possession of these pellet guns.

  11. Pneumatic pellet injector research at ORNL

    SciTech Connect

    Milora, S.L.; Combs, S.K.; Foster, C.A.; Schuresko, D.D.; Gouge, M.J.; Fisher, P.W.; Argo, B.E.; Barber, G.C.; Fehling, D.T.; Foust, C.R.

    1988-01-01

    Advanced pneumatic-injector-based pellet fueling systems are under development at Oak Ridge National Laboratory (ORNL) for fueling magnetically confined plasmas. The general approach is that of producing and accelerating frozen hydrogen isotope pellets at speeds in the range from 1 to 2 km/s and higher. Recently, ORNL provided pneumatic-based pellet fueling systems for the Tokamak Fusion Test Reactor (TFTR) and the Joint European Torus (JET), and a new simplified eight-shot injector has been developed for use on the Princeton Beta Experiment (PBX) and the Advanced Toroidal Facility (ATF). These long-pulse devices operate reliably at up to 1.5 km/s with pellet sizes ranging between 1 and 6 mm. In addition to these activities, ORNL is pursuing advanced technologies such as the electrothermal gun and the two-stage light-gas gun to achieve pellet velocities significantly in excess of 2 km/s and is carrying out a tritium proof-of-principle (TPOP) experiment in which the fabrication and acceleration of tritium pellets to 1.4 km/s were recently demonstrated. 27 refs., 10 figs.

  12. Gas adsorption capacity of wood pellets

    SciTech Connect

    Yazdanpanah, F.; Sokhansanj, Shahabaddine; Lim, C. Jim; Lau, A.; Bi, X. T.

    2016-02-03

    In this paper, temperature-programmed desorption (TPD) analysis was used to measure and analyze the adsorption of off-gases and oxygen by wood pellets during storage. Such information on how these gases interact with the material helps in the understanding of the purging/stripping behavior of off-gases to develop effective ventilation strategies for wood pellets. Steam-exploded pellets showed the lowest carbon dioxide (CO2) uptake compared to the regular and torrefied pellets. The high CO2 adsorption capacity of the torrefied pellets could be attributed to their porous structure and therefore greater available surface area. Quantifying the uptake of carbon monoxide by pellets was challenging due to chemical adsorption, which formed a strong bond between the material and carbon monoxide. The estimated energy of desorption for CO (97.8 kJ/mol) was very high relative to that for CO2 (7.24 kJ/mol), demonstrating the mechanism of chemical adsorption and physical adsorption for CO and CO2, respectively. As for oxygen, the strong bonds that formed between the material and oxygen verified the existence of chemical adsorption and formation of an intermediate material.

  13. The roles of inoculants' carbon source use in the biocontrol of potato scab disease.

    PubMed

    Sun, Pingping; Zhao, Xinbei; Shangguan, Nini; Chang, Dongwei; Ma, Qing

    2015-04-01

    Despite the application of multiple strains in the biocontrol of plant diseases, multistrain inoculation is still constrained by its inconsistency in the field. Nutrients, especially carbons, play an important role in the biocontrol processes. However, little work has been done on the systematic estimation of inoculants' carbon source use on biocontrol efficacies in vivo. In the present study, 7 nonpathogenic Streptomyces strains alone and in different combinations were inoculated as biocontrol agents against the potato scab disease, under field conditions and greenhouse treatments. The influence of the inoculants' carbon source use properties on biocontrol efficacies was investigated. The results showed that increasing the number of inoculated strains did not necessarily result in greater biocontrol efficacy in vivo. However, single strains with higher growth rates or multiple strains with less carbon source competition had positive effects on the biocontrol efficacies. These findings may shed light on optimizing the consistent biocontrol of plant disease with the consideration of inoculants' carbon source use properties.

  14. Changing paradigms of biocontrol in the developing and the developed world

    USDA-ARS?s Scientific Manuscript database

    Microbially based biocontrol of plant diseases differs fundamentally from chemical control systems, but pesticide regulations for microbial and chemical pesticides remain similar. However, the nature and advantages of chemicals and microbials are almost totally different. Biocontrol production, dist...

  15. Endophytic Fungi from Paddy

    PubMed Central

    Zakaria, Latiffah; Yaakop, Amira Suriaty; Salleh, Baharuddin; Zakaria, Maziah

    2010-01-01

    Endophytic fungi were isolated from different parts of healthy paddy plants (Oryza sativa). The most common endophytic fungal genus recovered was Fusarium, followed by Aspergillus, Curvularia, Penicillium, Gilmaniella and Arthrobotrys foliicola. Fusarium and Curvularia had higher occurrences in the seeds compared with the other fungi. Aspergillus was recovered mostly from leaf blades and Penicillium from the leaf sheath. Gilmaniella and A. foliicola were isolated only from the roots and leaf blade, respectively. The assemblage of endophytic fungi in healthy tissues of paddy plants may indicate that some of the fungi are possible latent pathogens and some may become saprophytic. PMID:24575194

  16. Properties of melt extruded enteric matrix pellets.

    PubMed

    Schilling, Sandra U; Shah, Navnit H; Waseem Malick, A; McGinity, James W

    2010-02-01

    The objective of this study was to investigate the properties of enteric matrix pellets that were prepared by hot-melt extrusion in a one-step, continuous process. Five polymers (Eudragit) L100-55, L100 and S100, Aqoat grades LF and HF) were investigated as possible matrix formers, and pellets prepared with Eudragit S100 demonstrated superior gastric protection and acceptable processibility. Extruded pellets containing Eudragit S100 and up to 40% theophylline released less than 10% drug over 2h in acid, however, the processibility and yields were compromised by the high amounts of the non-melting drug material in the formulation. Efficient plasticization of Eudragit S100 was necessary to reduce the polymer's glass transition temperature and melt viscosity. Five compounds including triethyl citrate, methylparaben, polyethylene glycol 8000, citric acid monohydrate and acetyltributyl citrate were investigated in terms of plasticization efficiency and preservation of the delayed drug release properties. The aqueous solubility of the plasticizer and its plasticization efficiency impacted the drug release rate from the matrix pellets. The use of water-soluble plasticizers resulted in a loss of gastric protection, whereas low drug release rates in acid were found for pellets containing insoluble plasticizers or no plasticizer, independent of the extent of Eudragit S100 plasticization. The release rate of theophylline in buffer pH 7.4 was faster for pellets that were prepared with efficient plasticizers. The microstructure and solid-state properties of plasticized pellets were further investigated by scanning electron microscopy and powder X-ray diffraction. Pellets prepared with efficient plasticizers (TEC, methylparaben, PEG 8000) exhibited matrices of low porosity, and the drug was homogeneously dispersed in its original polymorphic form. Pellets containing ATBC or citric acid monohydrate had to be extruded at elevated temperature and showed physical instabilities in

  17. Growth performance of calves fed microbially enhanced soy protein in pelleted starters.

    PubMed

    Senevirathne, N D; Anderson, J L; Gibbons, W R; Clapper, J A

    2017-01-01

    Our objective was to determine effects of feeding calves pelleted starters with microbially enhanced (fungi-treated) soy protein (MSP) in replacement of soybean meal (SBM) with different milk replacers (MR). Thirty-six Holstein calves (2 d old; 24 females, 12 males) in individual hutches were used in a 12-wk randomized complete block design study. Treatments were (1) MSP pellets with MR formulated for accelerated growth (28% crude protein, 18% fat; MSPA), (2) SBM pellets with MR formulated for accelerated growth (SBMA), and (3) MSP pellets with conventional MR (20% crude protein, 20% fat; MSPC). Pellets were similar except for 23% MSP or 23% SBM (dry matter basis). Pellets and water were fed ad libitum throughout the study. Feeding rates of MR on a dry matter basis were 0.37kg twice daily during wk 1, 0.45kg twice daily during wk 2 to 5, and 0.45kg once daily during wk 6. Intakes were recorded daily. Body weights, frame size measurements, and jugular blood samples were collected 2 d every 2 wk at 3 h after the morning feeding. Fecal grab samples were collected 5 times per d for 3 d during wk 12 and then composited by calf for analysis of apparent total-tract digestibility of nutrients using acid detergent insoluble ash as an internal marker. Total and starter pellet dry matter intake were greatest for calves fed SBMA and least for MSPC. Calves had similar average daily gain among treatments, but there was a treatment by week interaction and during the last few weeks of the study calves on MSPC had less body weight compared with MSPA or SBMA. Gain-to-feed ratio was similar among treatments; however, there was a treatment by week interaction. Serum glucose was similar among treatments. Plasma urea nitrogen was greatest for calves fed MSPA and least for MSPC. Plasma concentrations of IGF-1 were greatest for calves fed SBMA. Plasma concentrations of triglycerides were greatest for calves fed MSPC. Plasma concentrations of β-hydroxybutyrate had a treatment by time

  18. Ultrasonic vibration-assisted (UV-A) pelleting of wheat straw: a constitutive model for pellet density.

    PubMed

    Song, Xiaoxu; Zhang, Meng; Pei, Z J; Wang, Donghai

    2015-07-01

    Ultrasonic vibration-assisted (UV-A) pelleting can increase cellulosic biomass density and reduce biomass handling and transportation costs in cellulosic biofuel manufacturing. Effects of input variables on pellet density in UV-A pelleting have been studied experimentally. However, there are no reports on modeling of pellet density in UV-A pelleting. Furthermore, in the literature, most reported density models in other pelleting methods of biomass are empirical. This paper presents a constitutive model to predict pellet density in UV-A pelleting. With the predictive model, relations between input variables (ultrasonic power and pelleting pressure) and pellet density are predicted. The predicted relations are compared with those determined experimentally in the literature. Model predictions agree well with reported experimental results.

  19. Methods for the Evaluation of the Bioactivity and Biocontrol Potential of Species of Trichoderma.

    PubMed

    Steyaert, Johanna; Hicks, Emily; Kandula, Janaki; Kandula, Diwakar; Alizadeh, Hossein; Braithwaite, Mark; Yardley, Jessica; Mendoza-Mendoza, Artemio

    2016-01-01

    Members of the genus Trichoderma comprise the majority of commercial fungal biocontrol agents of plant diseases. As such, there is a wealth of information available on the analysis of their biocontrol potential and the mechanisms behind their superior abilities. This chapter aims to summarize the most common methods utilized within a Trichoderma biocontrol program for assessing the biological properties of individual strains.

  20. A 400-pellet feed system for the ORNL centrifuge pellet injector

    SciTech Connect

    Foster, C.A.; Qualls, A.L.; Baylor, L.R.; Schechter, D.E.; Dyer, G.R.; Milora, S.L.

    1993-11-01

    An improved and extended pellet fabrication and feed mechanism is being developed for the Oak Ridge National Laboratory (ORNL) centrifuge pellet injector that is presently installed on Tore Supra. This upgrade will extend the number of pellets available for a single-plasma discharge from 100 to 400. In addition, a new pusher and delivery system is expected to improve the performance of the device. As in the original system, deuterium ice is deposited from the gas phase on a liquid-helium-cooled rotating disk, forming a rim of solid deuterium. The rim of ice is machined to a parabolic profile from which pellets are pushed. In the new device, a stack of four ice rims are formed simultaneously, thereby increasing the capacity from 100 to 400 pellets. An improved method of ice formation has also been developed that produces clear ice. The pellet pusher and delivery system utilizes a four-axis, brushless dc servo system to precisely cut and deliver the pellets from the ice rim to the entrance of the centrifuge wheel. Pellets can be formed with sizes ranging from 2.5- to 4-mm diam at a rate of up to 8 per second. The operation of the injector is fully automated by a computer control system. The design and test results of the device are reported.

  1. Isolation of entomopathogenic fungi from soils and Ixodes scapularis (Acari: Ixodidae) ticks: prevalence and methods.

    PubMed

    Tuininga, Amy R; Miller, Jessica L; Morath, Shannon U; Daniels, Thomas J; Falco, Richard C; Marchese, Michael; Sahabi, Sadia; Rosa, Dieshia; Stafford, Kirby C

    2009-05-01

    Entomopathogenic fungi are commonly found in forested soils that provide tick habitat, and many species are pathogenic to Ixodes scapularis Say, the blacklegged tick. As a first step to developing effective biocontrol strategies, the objective of this study was to determine the best methods to isolate entomopathogenic fungal species from field-collected samples of soils and ticks from an Eastern deciduous forest where I. scapularis is common. Several methods were assessed: (1) soils, leaf litter, and ticks were plated on two types of media; (2) soils were assayed for entomopathogenic fungi using the Galleria bait method; (3) DNA from internal transcribed spacer (ITS) regions of the nuclear ribosomal repeat was extracted from pure cultures obtained from soils, Galleria, and ticks and was amplified and sequenced; and (4) DNA was extracted directly from ticks, amplified, and sequenced. We conclude that (1) ticks encounter potentially entomopathogenic fungi more often in soil than in leaf litter, (2) many species of potentially entomopathogenic fungi found in the soil can readily be cultured, (3) the Galleria bait method is a sufficiently efficient method for isolation of these fungi from soils, and (4) although DNA extraction from ticks was not possible in this study because of small sample size, DNA extraction from fungi isolated from soils and from ticks was successful and provided clean sequences in 100 and 73% of samples, respectively. A combination of the above methods is clearly necessary for optimal characterization of entomopathogenic fungi associated with ticks in the environment.

  2. Isolation of Entomopathogenic Fungi From Soils and Ixodes scapularis (Acari: Ixodidae) Ticks: Prevalence and Methods

    PubMed Central

    Tuininga, Amy R.; Miller, Jessica L.; Morath, Shannon U.; Daniels, Thomas J.; Falco, Richard C.; Marchese, Michael; Sahabi, Sadia; Rosa, Dieshia; Stafford, Kirby C.

    2009-01-01

    Entomopathogenic fungi are commonly found in forested soils that provide tick habitat, and many species are pathogenic to Ixodes scapularis Say, the blacklegged tick. As a first step to developing effective biocontrol strategies, the objective of this study was to determine the best methods to isolate entomopathogenic fungal species from field-collected samples of soils and ticks from an Eastern deciduous forest where I. scapularis is common. Several methods were assessed: (1) soils, leaf litter, and ticks were plated on two types of media; (2) soils were assayed for entomopathogenic fungi using the Galleria bait method; (3) DNA from internal transcribed spacer (ITS) regions of the nuclear ribosomal repeat was extracted from pure cultures obtained from soils, Galleria, and ticks and was amplified and sequenced; and (4) DNA was extracted directly from ticks, amplified, and sequenced. We conclude that (1) ticks encounter potentially entomopathogenic fungi more often in soil than in leaf litter, (2) many species of potentially entomopathogenic fungi found in the soil can readily be cultured, (3) the Galleria bait method is a sufficiently efficient method for isolation of these fungi from soils, and (4) although DNA extraction from ticks was not possible in this study because of small sample size, DNA extraction from fungi isolated from soils and from ticks was successful and provided clean sequences in 100 and 73% of samples, respectively. A combination of the above methods is clearly necessary for optimal characterization of entomopathogenic fungi associated with ticks in the environment. PMID:19496427

  3. The importance of chorismate mutase in the biocontrol potential of Trichoderma parareesei

    PubMed Central

    Pérez, Esclaudys; Rubio, M. Belén; Cardoza, Rosa E.; Gutiérrez, Santiago; Bettiol, Wagner; Monte, Enrique; Hermosa, Rosa

    2015-01-01

    Species of Trichoderma exert direct biocontrol activity against soil-borne plant pathogens due to their ability to compete for nutrients and to inhibit or kill their targets through the production of antibiotics and/or hydrolytic enzymes. In addition to these abilities, Trichoderma spp. have beneficial effects for plants, including the stimulation of defenses and the promotion of growth. Here we study the role in biocontrol of the T. parareesei Tparo7 gene, encoding a chorismate mutase (CM), a shikimate pathway branch point leading to the production of aromatic amino acids, which are not only essential components of protein synthesis but also the precursors of a wide range of secondary metabolites. We isolated T. parareesei transformants with the Tparo7 gene silenced. Compared with the wild-type, decreased levels of Tparo7 expression in the silenced transformants were accompanied by reduced CM activity, lower growth rates on different culture media, and reduced mycoparasitic behavior against the phytopathogenic fungi Rhizoctonia solani, Fusarium oxysporum and Botrytis cinerea in dual cultures. By contrast, higher amounts of the aromatic metabolites tyrosol, 2-phenylethanol and salicylic acid were detected in supernatants from the silenced transformants, which were able to inhibit the growth of F. oxysporum and B. cinerea. In in vitro plant assays, Tparo7-silenced transformants also showed a reduced capacity to colonize tomato roots. The effect of Tparo7-silencing on tomato plant responses was examined in greenhouse assays. The growth of plants colonized by the silenced transformants was reduced and the plants exhibited an increased susceptibility to B. cinerea in comparison with the responses observed for control plants. In addition, the plants turned yellowish and were defective in jasmonic acid- and ethylene-regulated signaling pathways which was seen by expression analysis of lipoxygenase 1 (LOX1), ethylene-insensitive protein 2 (EIN2) and pathogenesis

  4. The importance of chorismate mutase in the biocontrol potential of Trichoderma parareesei.

    PubMed

    Pérez, Esclaudys; Rubio, M Belén; Cardoza, Rosa E; Gutiérrez, Santiago; Bettiol, Wagner; Monte, Enrique; Hermosa, Rosa

    2015-01-01

    Species of Trichoderma exert direct biocontrol activity against soil-borne plant pathogens due to their ability to compete for nutrients and to inhibit or kill their targets through the production of antibiotics and/or hydrolytic enzymes. In addition to these abilities, Trichoderma spp. have beneficial effects for plants, including the stimulation of defenses and the promotion of growth. Here we study the role in biocontrol of the T. parareesei Tparo7 gene, encoding a chorismate mutase (CM), a shikimate pathway branch point leading to the production of aromatic amino acids, which are not only essential components of protein synthesis but also the precursors of a wide range of secondary metabolites. We isolated T. parareesei transformants with the Tparo7 gene silenced. Compared with the wild-type, decreased levels of Tparo7 expression in the silenced transformants were accompanied by reduced CM activity, lower growth rates on different culture media, and reduced mycoparasitic behavior against the phytopathogenic fungi Rhizoctonia solani, Fusarium oxysporum and Botrytis cinerea in dual cultures. By contrast, higher amounts of the aromatic metabolites tyrosol, 2-phenylethanol and salicylic acid were detected in supernatants from the silenced transformants, which were able to inhibit the growth of F. oxysporum and B. cinerea. In in vitro plant assays, Tparo7-silenced transformants also showed a reduced capacity to colonize tomato roots. The effect of Tparo7-silencing on tomato plant responses was examined in greenhouse assays. The growth of plants colonized by the silenced transformants was reduced and the plants exhibited an increased susceptibility to B. cinerea in comparison with the responses observed for control plants. In addition, the plants turned yellowish and were defective in jasmonic acid- and ethylene-regulated signaling pathways which was seen by expression analysis of lipoxygenase 1 (LOX1), ethylene-insensitive protein 2 (EIN2) and pathogenesis

  5. Diversity and biochemical features of culturable fungi from the coastal waters of Southern China

    PubMed Central

    2014-01-01

    Fungi play a major role in various biogeochemical cycles of terrestrial and marine ecosystems. However, fungi in marine environments remain to be one of the most under-studied microbial groups. This study investigates the diversity of planktonic fungi from the coastal habitat off Pearl River Delta (China) using culture-dependent approach. A total of 22 fungi and 9 yeast isolates were recovered from 30 seawater and 2 sediment samples. Microscopic and ITS rRNA gene sequence analyses revealed that most of the fungi belonged to the phylum Ascomycota and Basidiomycota with a very small percentage (3%) of the subphylum Mucoromycotina of the Phylum Zygomycota. Most of these fungal isolates exhibited considerable production of extracellular enzymes, cellulase, lipase and laccase. Fungal isolates of two genera Mucor and Aspergillus sp. demonstrated pelletization capability over a wide range of pH, suggesting them as potential agents towards algae harvesting and wastewater treatment. PMID:25401065

  6. Diversity and biochemical features of culturable fungi from the coastal waters of Southern China.

    PubMed

    Li, Li; Singh, Purnima; Liu, Ying; Pan, Shenquan; Wang, Guangyi

    2014-01-01

    Fungi play a major role in various biogeochemical cycles of terrestrial and marine ecosystems. However, fungi in marine environments remain to be one of the most under-studied microbial groups. This study investigates the diversity of planktonic fungi from the coastal habitat off Pearl River Delta (China) using culture-dependent approach. A total of 22 fungi and 9 yeast isolates were recovered from 30 seawater and 2 sediment samples. Microscopic and ITS rRNA gene sequence analyses revealed that most of the fungi belonged to the phylum Ascomycota and Basidiomycota with a very small percentage (3%) of the subphylum Mucoromycotina of the Phylum Zygomycota. Most of these fungal isolates exhibited considerable production of extracellular enzymes, cellulase, lipase and laccase. Fungal isolates of two genera Mucor and Aspergillus sp. demonstrated pelletization capability over a wide range of pH, suggesting them as potential agents towards algae harvesting and wastewater treatment.

  7. Development of repetitive railgun pellet accelerator and steady-state pellet supply system

    SciTech Connect

    Oda, Y.; Onozuka, M.; Azuma, K.; Kasai, S.; Hasegawa, K.

    1995-12-31

    A railgun system for repetitive high-speed pellet acceleration and steady-state pellet supply system has been developed and investigated. Using a 2m-long railgun system, the hydrogen pellet was accelerated to 2.6km/sec by the supplied energy of 1.7kJ. It is expected that the hydrogen pellet can be accelerated to 3km/sec using the present pneumatic pellet accelerator and a 2m-long augment railgun. Screw-driven hydrogen-isotope filament extruding system has been fabricated and will be tested to examine its applicability to the steady-state extrusion of the solid hydrogen-isotope filament.

  8. Vorticella sp: Prospective Mosquito Biocontrol Agent

    PubMed Central

    Patil, Chandrashekhar Devidas; Narkhede, Chandrakant Prakash; Suryawanshi, Rahul Khushal; Patil, Satish Vitthal

    2016-01-01

    Background: Considering the disadvantages of chemical insecticides, we aimed to evaluate Vorticella parasites for control of mosquito larvae of Anopheles stephensi and Aedes aegypti at different larval stages. Methods: Vorticella sp infected mosquito larvae were crushed in the 0.85% saline and homogenized well to get Vorticella in suspension. The effects of Vorticella sp infections on larval development were investigated by inoculating protozoan on different larval instars of An. stephensi and Ae. aegypti and observed under light microscope. Lethal time of the Vorticella infected larvae at different stages was calculated. Results: First and 2nd larval instars of both An. stephensi and Ae. aegypti did not show signs of infection by Vorticella sp., whereas 3rd instars of An. stephensi showed more Vorticella infection than those of Ae. aegypti. However, 4th larval instars of both mosquitoes were heavily infected with Vorticella parasite which was responsible for sluggish movements of larvae and eventually death. Moreover, parasites (Vorticella spp) were responsible for more than 90% reduction in adult emergence for both infected An. stephensi and Ae. aegypti. Conclusion: This study provides insights for mosquito larvicidal action of surface parasite Vorticella on different larval stages of An. stephensi and Ae. Aegypti. It could be suggested as a potential candidate in mosquito biocontrol programs. PMID:28032113

  9. The enhanced ASDEX Upgrade pellet centrifuge launcher

    NASA Astrophysics Data System (ADS)

    Plöckl, B.; Lang, P. T.

    2013-10-01

    Pellets played an important role in the program of ASDEX Upgrade serving both for investigations on efficient particle fuelling and high density scenarios but also for pioneering work on Edge Localised Mode (ELM) pacing and mitigation. Initially designed for launching fuelling pellets from the magnetic low field side, the system was converted already some time ago to inject pellets from the magnetic high field side as much higher fuelling efficiency was found using this configuration. In operation for more than 20 years, the pellet launching system had to undergo a major revision and upgrading, in particular of its control system. Furthermore, the control system installed adjacent to the launcher had to be transferred to a more distant location enforcing a complete galvanic separation from torus potential and a fully remote control solution. Changing from a hybrid system consisting of PLC S5/S7 and some hard wired relay control to a state of the art PLC system allowed the introduction of several new operational options enabling more flexibility in the pellet experiments. This article describes the new system architecture of control hardware and software, the operating procedure, and the extended operational window. First successful applications for ELM pacing and triggering studies are presented as well as utilization for the development of high density scenarios.

  10. Lithium Pellet Injector Development for NSTX

    SciTech Connect

    G. Gettelfinger; J. Dong; R. Gernhardt; H. Kugel; P. Sichta; J. Timberlake

    2003-12-04

    A pellet injector suitable for the injection of lithium and other low-Z pellets of varying mass into plasmas at precise velocities from 5 to 500 m/s is being developed for use on NSTX (National Spherical Torus Experiment). The ability to inject low-Z impurities will significantly expand NSTX experimental capability for a broad range of diagnostic and operational applications. The architecture employs a pellet-carrying cartridge propelled through a guide tube by deuterium gas. Abrupt deceleration of the cartridge at the end of the guide tube results in the pellet continuing along its intended path, thereby giving controlled reproducible velocities for a variety of pellets materials and a reduced gas load to the torus. The planned injector assembly has four hundred guide tubes contained in a rotating magazine with eight tubes provided for injection into plasmas. A PC-based control system is being developed as well and will be described elsewhere in these Proceedings. The development path and mechanical performance of the injector will be described.

  11. The enhanced ASDEX Upgrade pellet centrifuge launcher.

    PubMed

    Plöckl, B; Lang, P T

    2013-10-01

    Pellets played an important role in the program of ASDEX Upgrade serving both for investigations on efficient particle fuelling and high density scenarios but also for pioneering work on Edge Localised Mode (ELM) pacing and mitigation. Initially designed for launching fuelling pellets from the magnetic low field side, the system was converted already some time ago to inject pellets from the magnetic high field side as much higher fuelling efficiency was found using this configuration. In operation for more than 20 years, the pellet launching system had to undergo a major revision and upgrading, in particular of its control system. Furthermore, the control system installed adjacent to the launcher had to be transferred to a more distant location enforcing a complete galvanic separation from torus potential and a fully remote control solution. Changing from a hybrid system consisting of PLC S5/S7 and some hard wired relay control to a state of the art PLC system allowed the introduction of several new operational options enabling more flexibility in the pellet experiments. This article describes the new system architecture of control hardware and software, the operating procedure, and the extended operational window. First successful applications for ELM pacing and triggering studies are presented as well as utilization for the development of high density scenarios.

  12. The enhanced ASDEX Upgrade pellet centrifuge launcher

    SciTech Connect

    Plöckl, B.; Lang, P. T.

    2013-10-15

    Pellets played an important role in the program of ASDEX Upgrade serving both for investigations on efficient particle fuelling and high density scenarios but also for pioneering work on Edge Localised Mode (ELM) pacing and mitigation. Initially designed for launching fuelling pellets from the magnetic low field side, the system was converted already some time ago to inject pellets from the magnetic high field side as much higher fuelling efficiency was found using this configuration. In operation for more than 20 years, the pellet launching system had to undergo a major revision and upgrading, in particular of its control system. Furthermore, the control system installed adjacent to the launcher had to be transferred to a more distant location enforcing a complete galvanic separation from torus potential and a fully remote control solution. Changing from a hybrid system consisting of PLC S5/S7 and some hard wired relay control to a state of the art PLC system allowed the introduction of several new operational options enabling more flexibility in the pellet experiments. This article describes the new system architecture of control hardware and software, the operating procedure, and the extended operational window. First successful applications for ELM pacing and triggering studies are presented as well as utilization for the development of high density scenarios.

  13. Biotechnology of marine fungi.

    PubMed

    Damare, Samir; Singh, Purnima; Raghukumar, Seshagiri

    2012-01-01

    Filamentous fungi are the most widely used eukaryotes in industrial and pharmaceutical applications. Their biotechnological uses include the production of enzymes, vitamins, polysaccharides, pigments, lipids and others. Marine fungi are a still relatively unexplored group in biotechnology. Taxonomic and habitat diversity form the basis for exploration of marine fungal biotechnology. This review covers what is known of the potential applications of obligate and marine-derived fungi obtained from coastal to the oceanic and shallow water to the deep-sea habitats. Recent studies indicate that marine fungi are potential candidates for novel enzymes, bioremediation, biosurfactants, polysaccharides, polyunsaturated fatty acids and secondary metabolites. Future studies that focus on culturing rare and novel marine fungi, combined with knowledge of their physiology and biochemistry will provide a firm basis for marine mycotechnology.

  14. Saprotrophic competitiveness and biocontrol fitness of a genetically modified strain of the plant-growth-promoting fungus Trichoderma hamatum GD12.

    PubMed

    Ryder, Lauren S; Harris, Beverley D; Soanes, Darren M; Kershaw, Michael J; Talbot, Nicholas J; Thornton, Christopher R

    2012-01-01

    Trichoderma species are ubiquitous soil fungi that hold enormous potential for the development of credible alternatives to agrochemicals and synthetic fertilizers in sustainable crop production. In this paper, we show that substantial improvements in plant productivity can be met by genetic modification of a plant-growth-promoting and biocontrol strain of Trichoderma hamatum, but that these improvements are obtained in the absence of disease pressure only. Using a quantitative monoclonal antibody-based ELISA, we show that an N-acetyl-β-d-glucosaminidase-deficient mutant of T. hamatum, generated by insertional mutagenesis of the corresponding gene, has impaired saprotrophic competitiveness during antagonistic interactions with Rhizoctonia solani in soil. Furthermore, its fitness as a biocontrol agent of the pre-emergence damping-off pathogen Sclerotinia sclerotiorum is significantly reduced, and its ability to promote plant growth is constrained by the presence of both pathogens. This work shows that while gains in T. hamatum-mediated plant-growth-promotion can be met through genetic manipulation of a single beneficial trait, such a modification has negative impacts on other aspects of its biology and ecology that contribute to its success as a saprotrophic competitor and antagonist of soil-borne pathogens. The work has important implications for fungal morphogenesis, demonstrating a clear link between hyphal architecture and secretory potential. Furthermore, it highlights the need for a holistic approach to the development of genetically modified Trichoderma strains for use as crop stimulants and biocontrol agents in plant agriculture.

  15. Effect of bacterial antagonists on lettuce: active biocontrol of Rhizoctonia solani and negligible, short-term effects on nontarget microorganisms.

    PubMed

    Scherwinski, Katja; Grosch, Rita; Berg, Gabriele

    2008-04-01

    The aim of this study was to assess the biocontrol efficacy against Rhizoctonia solani of three bacterial antagonists introduced into naturally Rhizoctonia-infested lettuce fields and to analyse their impact on the indigenous plant-associated bacteria and fungi. Lettuce seedlings were inoculated with bacterial suspensions of two endophytic strains, Serratia plymuthica 3Re4-18 and Pseudomonas trivialis 3Re2-7, and with the rhizobacterium Pseudomonas fluorescens L13-6-12 7 days before and 5 days after planting in the field. Similar statistically significant biocontrol effects were observed for all applied bacterial antagonists compared with the uninoculated control. Single-strand conformation polymorphism analysis of 16S rRNA gene or ITS1 fragments revealed a highly diverse rhizosphere and a less diverse endophytic microbial community for lettuce. Representatives of several bacterial (Alpha-, Beta- and Gammaproteobacteria, Firmicutes, Bacteriodetes), fungal (Ascomycetes, Basidiomycetes) and protist (Oomycetes) groups were present inside or on lettuce plants. Surprisingly, given that lettuce is a vegetable that is eaten raw, species of genera such as Flavobacterium, Burkholderia, Staphylococcus, Cladosporium and Aspergillus, which contain potentially human pathogenic strains, were identified. Analysis of the indigenous bacterial and endophytic fungal populations revealed only negligible, short-term effects resulting from the bacterial treatments, and that they were more influenced by field site, plant growth stage and microenvironment.

  16. Bacillus methylotrophicus Strain NKG-1, Isolated from Changbai Mountain, China, Has Potential Applications as a Biofertilizer or Biocontrol Agent

    PubMed Central

    Ge, Beibei; Liu, Binghua; Nwet, Thinn Thinn; Zhao, Wenjun; Shi, Liming; Zhang, Kecheng

    2016-01-01

    Chemical pesticides are widely used in agriculture, which endangers both environmental health and food safety. Biocontrol is an environmentally-friendly and cost-effective green technique in environmental protection and agricultural production; it generally uses selected bioresources, including beneficial microorganisms. We isolated a novel bacterial strain (NKG-1) from the rare dormant volcanic soils of Changbai Mountain in China’s Jilin Province. The strain was identified as Bacillus methylotrophicus using morphological, biochemical, physiological, and phylogenetic 16S rDNA sequencing data. This strain was able to suppress mycelial growth and conidial germination of numerous plant pathogenic fungi on solid media. A greenhouse experiment showed that application of NKG-1 fermentation broth prior to inoculation of Botrytis cinerea, the cause of gray tomato mold, inhibited growth of the mold by 60%. Furthermore, application of a 100× dilution of NKG-1 fermentation broth to tomato seedlings yielded a significant increase in seedling fresh weight (27.4%), seedling length (12.5%), and root length (57.7%) compared to the control. When the same dosage was applied in the field, we observed increases in tomato plant height (14.7%), stem diameter (12.7%), crown width (16.3%), and maximum fruit diameter (11.5%). These results suggest that NKG-1 has potential commercial application as a biofertilizer or biocontrol agent. PMID:27832162

  17. Bacillus methylotrophicus Strain NKG-1, Isolated from Changbai Mountain, China, Has Potential Applications as a Biofertilizer or Biocontrol Agent.

    PubMed

    Ge, Beibei; Liu, Binghua; Nwet, Thinn Thinn; Zhao, Wenjun; Shi, Liming; Zhang, Kecheng

    2016-01-01

    Chemical pesticides are widely used in agriculture, which endangers both environmental health and food safety. Biocontrol is an environmentally-friendly and cost-effective green technique in environmental protection and agricultural production; it generally uses selected bioresources, including beneficial microorganisms. We isolated a novel bacterial strain (NKG-1) from the rare dormant volcanic soils of Changbai Mountain in China's Jilin Province. The strain was identified as Bacillus methylotrophicus using morphological, biochemical, physiological, and phylogenetic 16S rDNA sequencing data. This strain was able to suppress mycelial growth and conidial germination of numerous plant pathogenic fungi on solid media. A greenhouse experiment showed that application of NKG-1 fermentation broth prior to inoculation of Botrytis cinerea, the cause of gray tomato mold, inhibited growth of the mold by 60%. Furthermore, application of a 100× dilution of NKG-1 fermentation broth to tomato seedlings yielded a significant increase in seedling fresh weight (27.4%), seedling length (12.5%), and root length (57.7%) compared to the control. When the same dosage was applied in the field, we observed increases in tomato plant height (14.7%), stem diameter (12.7%), crown width (16.3%), and maximum fruit diameter (11.5%). These results suggest that NKG-1 has potential commercial application as a biofertilizer or biocontrol agent.

  18. A Gyrotron-Powered Pellet Accelerator

    NASA Astrophysics Data System (ADS)

    Perkins, F. W.; Parks, P. B.

    2005-10-01

    Plans for fuelling ITER call for accelerated pellets which propagate in guide-tubes. The tubes undergo 90 bends so that the pellets can enter the plasma along the high field-side of the separatrix. Both theory and experiment find that for V>= 500m/s, centrifugal force in the bends will fracture the pellets and elongate the cloud of debris. This contribution outlines the design of a plasma accelerator sufficiently flexible so that 90 bends can be avoided for the high-speed portions of the trajectory. The key element is to recognize that the guide tubes can also serve as a waveguide for millimeter waves. Operation proceeds as follows: A pellet is introduced into a guide tube of diameter 5mm at low velocity ˜10m/s and propagates until the remaining trajectory is straight and normal to separatrix. At this point, a 1 MW gyrotron is energized and power propagates until it encounters the pellet. The pellet has a 4-region structure and acts as a gun. The rear region (5mm) is diamond which passes the millimeter waves and provides inertia. Next is a 2mm region of frozen D doped with lithium which adsorbs the millimeter waves and vaporizes. The third region is a thin lithium layer which is several skin depths in extent and reflects millimeter waves. The 5 mm front region is a frozen DT bullet accelerated by the vaporized absorbing layer. The bullet now has a straight trajectory. 1D simulations of the gun will be presented.

  19. Red Light-enhanced Phytochrome Pelletability

    PubMed Central

    Pratt, Lee H.; Marmé, Dieter

    1976-01-01

    Red light-enhanced pelletability of phytochrome was observed in extracts of all 11 plants tested: Avena sativa L., Secale cereale L., Zea mays L., Cucurbita pepo L., Sinapis alba L., Pisum sativum L., Helianthus anuus L., Raphanus sativus L., Glycine max (L.) Merr., Phaseolus vulgaris L., and Lupinus albus L. This enhanced pelletability was observed in all 11 plants following in situ irradiation (in vivo binding) but only in Sinapis and Cucurbita after irradiation of crude extracts (in vitro binding). In vivo binding was not strongly dependent upon pH and, with few exceptions, was not markedly sensitive to high salt concentration, whereas in vitro binding was completely reversed by both high pH and high salt concentration. However, both binding phenomena were observed only with a divalent cation in the extract buffer. In vivo binding was further characterized using Avena which showed an increase in pelletability from less than 10% in dark control extracts to more than 60% in extracts of red light-irradiated shoots. The half-life for binding was 40 seconds at 0.5 C and was strongly temperature-dependent, binding being complete within 5 to 10 sec at 22 C. If pelletable phytochrome in the far red-absorbing form was photoconverted back to the red-absorbing form in situ, phytochrome was released from the pelletable condition with a half-life of 25 minutes at 25 C and 100 minutes at both 13 C and 3 C. No cooperativity in red light-enhanced pelletability with respect to phytochrome-far red-absorbing form was observed. PMID:16659745

  20. Virulence of selected entomopathogenic fungi against the olive fruit fly and their potential for biocontrol

    USDA-ARS?s Scientific Manuscript database

    The olive fruit fly, Bactrocera oleae (Diptera: Tephritidae), is the most serious pest of cultivated olives worldwide. Its recent invasion into North America, specifically California, has initiated renewed interest in management strategies for this pest. Research into classical biological control ha...

  1. Treatment of colored effluents with lignin-degrading enzymes: an emerging role of marine-derived fungi.

    PubMed

    Raghukumar, Chandralata; D'Souza-Ticlo, Donna; Verma, Ashutosh Kumar

    2008-01-01

    Some of the industries that discharge highly colored effluents are paper and pulp mills, textiles and dye-making industries, alcohol distilleries, and leather industries. Terrestrial white-rot basidiomycetous fungi and their lignin-degrading enzymes laccase, manganese-peroxidase and lignin peroxidases are useful in the treatment of colored industrial effluents and other xenobiotics. Free mycelia, mycelial pellets, immobilized fungi or their lignin-degrading enzymes from terrestrial fungi have been reported in treatment of several effluents. Marine obligate or facultative (marine-derived) fungi may have unique properties but have not been explored sufficiently for this purpose. This article presents a critical review of bioremediation potential of such fungi and their lignin-degrading enzymes in comparison with the state-of-the-art in terrestrial white-rot fungi.

  2. Pellet ablation and ablation model development

    SciTech Connect

    Houlberg, W.A.

    1989-01-01

    A broad survey of pellet ablation is given, based primarily on information presented at this meeting. The implications of various experimental observations for ablation theory are derived from qualitative arguments of the physics involved. The major elements of a more complete ablation theory are then outlined in terms of these observations. This is followed by a few suggestions on improving the connections between theory and experimental results through examination of ablation data. Although this is a rather aggressive undertaking for such a brief (and undoubtedly incomplete) assessment, some of the discussion may help us advance the understanding of pellet ablation. 17 refs.

  3. International Trade of Wood Pellets (Brochure)

    SciTech Connect

    Not Available

    2013-05-01

    The production of wood pellets has increased dramatically in recent years due in large part to aggressive emissions policy in the European Union; the main markets that currently supply the European market are North America and Russia. However, current market circumstances and trade dynamics could change depending on the development of emerging markets, foreign exchange rates, and the evolution of carbon policies. This fact sheet outlines the existing and potential participants in the wood pellets market, along with historical data on production, trade, and prices.

  4. CO{sub 2} pellet blasting studies

    SciTech Connect

    Archibald, K.E.

    1997-01-01

    Initial tests with CO{sub 2} pellet blasting as a decontamination technique were completed in 1993 at the Idaho Chemical Processing Plant (ICPP) at the Idaho National Engineering Laboratory (INEL). During 1996, a number of additional CO{sub 2} pellet blasting studies with Alpheus Cleaning Technologies, Oak Ridge National Laboratory, and Pennsylvania State University were conducted. After the testing with Alpheus was complete, an SDI-5 shaved CO{sub 2} blasting unit was purchased by the ICPP to test and determine its capabilities before using in ICPP decontamination efforts. Results of the 1996 testing will be presented in this report.

  5. Pellet impact drilling operational parameters: experimental research

    NASA Astrophysics Data System (ADS)

    Kovalyov, A. V.; Ryabchikov, S. Ya; Isaev, Ye D.; Aliev, F. R.; Gorbenko, M. V.; Baranova, A. V.

    2015-02-01

    The article deals with the study of particle-impact drilling that is designed to enhance the rate-of-penetration function in hard and tough drilling environments. It contains the experimental results on relation between drilling parameters and drilling efficiency, the experiments being conducted by means of a specially designed laboratory model. To interpret the results properly a high-speed camera was used to capture the pellet motion. These results can be used to choose optimal parameters, as well as to develop enhanced design of ejector pellet impact drill bits.

  6. Patents on Endophytic Fungi.

    PubMed

    Gokhale, M; Gupta, D; Gupta, U; Faraz, R; Sandhu, S S

    2017-01-01

    Endophytic fungi are taxonomically and ecologically heterogeneous group of organisms, mainly belonging to the Ascomycotina and Deuteromycotina. Endophytes usually produce the enzymes necessary for the colonization of plant tissues. Endophytes are able to utilize components of plant cells without disturbing host metabolism, which is confirmed by isozyme analysis and studies on substrate utilization. The patents related to enzymes and metabolites produced by endophytic fungi are associated with their ecological significance. Application of metabolites and growth promoting factors produced from endophytic fungi, in the pharmaceutical and agricultural industries, is now well established. The patents on secretion of extracellular enzymes in vitro by endophytic fungi needed for cell wall degradation, support the hypothesis that fungal endophytes represent a group of organisms specialized to live within plant tissue. This review presents the patents granted on different aspects of endophytic fungi for the last 11 years. This expresses the scenario and impact of these patents regarding significance in human society. In the last few years, research and inventions regarding the different aspects of endophytic fungi beneficial for host plant as well as for human beings have been carried out, which is supported by the increasing number of patents granted on endophytic fungi. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  7. Taxonomy of Allergenic Fungi.

    PubMed

    Levetin, Estelle; Horner, W Elliott; Scott, James A

    2016-01-01

    The Kingdom Fungi contains diverse eukaryotic organisms including yeasts, molds, mushrooms, bracket fungi, plant rusts, smuts, and puffballs. Fungi have a complex metabolism that differs from animals and plants. They secrete enzymes into their surroundings and absorb the breakdown products of enzyme action. Some of these enzymes are well-known allergens. The phylogenetic relationships among fungi were unclear until recently because classification was based on the sexual state morphology. Fungi lacking an obvious sexual stage were assigned to the artificial, now-obsolete category, "Deuteromycetes" or "Fungi Imperfecti." During the last 20 years, DNA sequencing has resolved 8 fungal phyla, 3 of which contain most genera associated with important aeroallergens: Zygomycota, Ascomycota, and Basidiomycota. Advances in fungal classification have required name changes for some familiar taxa. Because of regulatory constraints, many fungal allergen extracts retain obsolete names. A major benefit from this reorganization is that specific immunoglobulin E (IgE) levels in individuals sensitized to fungi appear to closely match fungal phylogenetic relationships. This close relationship between molecular fungal systematics and IgE sensitization provides an opportunity to systematically look at cross-reactivity and permits representatives from each taxon to serve as a proxy for IgE to the group. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  8. Settling behaviour of pellet flocs in pelleting flocculation process: analysis through operational conditions.

    PubMed

    Gang, Zhang; Ting-lin, Huang; Chi, Tan; Zhan-peng, Li; Wen-jie, He; Hong-da, Han; Chen, Li

    2010-01-01

    Pellet flocs' settling velocity is an important parameter in the pelleting flocculation blanket (PFB) process, hence, it is necessary to investigate flocs' settling behaviour to achieve the optimum operation parameters of the process. To investigate the settling behaviour of pellets under different operational conditions, a dynamic experiment was carried out to concentrate ferric flocs sludge by pelleting flocculation blanket (PFB) process with the scale of 0.5-1.2 m3/h. Under different operating conditions such as raw water concentration, polyacrylamide (PAM) dosage, up-flow rate, and agitation speed, pellet particles were sampled from different locations of the blanket in various operating stages to analyze pellet size, setting velocity, and porosity. Experimental results indicated that, when the PAM dosage increased from 0.59 mg/L to 1.18 mg/L, pellets size would flocculated from 2.25 mm to 3.52 mm with the settling velocity accelerated from 3.28 mm/s to 7.37 mm/s, while under the same up-flow rate, agitation intensity and PAM dosage, accompany with the raw water concentration increased from 216 mg/L to 840 mg/L, pellets settling velocity would improved from 6.03 mm/s to 13.6 mm/s. Under the experimental condition, along with the up-flow rate increased from 13.3 m/h to 40 m/h, pellets settling velocity would decreased from 4.39 mm/s to 3.42 mm/s due to its lower density.

  9. Pellet ablation and temperature profile measurements in TFTR

    SciTech Connect

    Owens, D.K.; Schmidt, G.L.; Cavallo, A.; Grek, B.; Hulse, R.; Johnson, D.; Mansfield, D.; McNeill, D.; Park, H.; Taylor, G.

    1988-01-01

    Single and multiple deuterium pellets have been injected into a variety of TFTR plasmas, including ohmically heated plasmas with wide range of electron temperatures, neutral beam heated plasmas at several NBI powers and high T/sub e/, post NBI plasmas. Pellet penetration into these plasmas was determined by measuring the pellet speed and duration of the H/sub ..cap alpha..//D/sub ..cap alpha../ light emission during pellet ablation in the plasma. These penetration measurements are compared to the predicted penetration computed using the ablation model developed by Oak Ridge National Laboratory. The plasma density profiles before and after pellet injection are used to estimate the number of particles deposited in the plasma. The plasma particle increase compared to the estimated number of atoms in the pellet yields a measure of the fueling efficiency of pellets in TFTR. The ablation cloud parameters are discussed based on polychromater measurements of the H/sub ..cap alpha..//D/sub ..cap alpha../ line emission from the neutral cloud surrounding the pellet. The electron temperature profile evolution after pellet injection is examined for the case of multiple pellet injection into an ohmically heated plasma. The ORNL pellet ablation code was used to compare measured pellet penetration depths with a theoretical model. The measured input parameters to the model are the electron density and temperature profiles, the neutral beam heating profile, the neutral density profile, the pellet size, pellet speed and pellet composition. The free parameter in the model is the thickness of the neutral cloud surrounding the pellet. This parameter is adjusted to arrive at a reasonable agreement between measured and calculated pellet penetration depths. The output of the model which is directly comparable to experiment is the calculated ablation rate. It is assumed that the broad-band H/sub ..cap alpha..//D/sub ..cap alpha../ emission is proportional to the ablation rate.

  10. Biological control of toxigenic citrus and papaya-rotting fungi by Streptomyces violascens MT7 and its extracellular metabolites.

    PubMed

    Choudhary, Bharti; Nagpure, Anand; Gupta, Rajinder K

    2015-12-01

    An Indian indigenous, Loktak Lake soil isolate Streptomyces violascens MT7 was assessed for its biocontrol potential both in vitro and in vivo against toxigenic fruit-rotting fungi. Strain MT7 exhibited broad-spectrum antifungal activity against various pathogenic postharvest fungi of citrus and papaya. In shake-flask fermentation, antagonist S. violascens MT7 highly produced extracellular antifungal metabolites in early stationary growth phase in glucose-yeast extract-malt extract (M93) broth. Both extracellular culture fluid (ECF) and its n-butanol extract showed significant broad-spectrum fungal mycelial inhibition of several tested fruit-rotting fungi. Antifungal metabolite was found to be heat stable, nonpeptidic, and polyene type antibiotic. The lowest minimum inhibitory concentration (MIC) of n-butanol extract against Colletotrichum gloeosporioides MTCC 9664 and Aspergillus niger MTCC 281 was 0.0312 and 0.0625 mg/ml, respectively. Purification of n-butanol extract through silica gel chromatography resulted in partial purification of bioactive metabolite and the TLC autobiography revealed the presence of single antifungal metabolite with Rf value of 0.755. In vivo bioassays demonstrated the biocontrol potential of tested biocontrol agents on fruit-rotting fungi. Use of cell suspension of S. violascens MT7, extracellular metabolite(s), and n-butanol extract significantly (p < 0.05) reduced sour-rot development on Citrus reticulata Blanco (oranges) and soft-rot development on papaya fruits. Therefore, these results strongly suggest a high potential for application of S. violascens MT7 and its extracellular metabolites as an effective eco-friendly alternative to synthetic fungicides for controlling toxigenic citrus and papaya-rotting fungi. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Yeasts from native Brazilian Cerrado plants: Occurrence, diversity and use in the biocontrol of citrus green mould.

    PubMed

    Sperandio, Eugenio Miranda; do Vale, Helson Mario Martins; Moreira, Geisianny Augusta Monteiro

    2015-11-01

    Yeasts are some of the most important postharvest biocontrol agents. Postharvest oranges frequently deteriorate due to green mould (Penicillium digitatum), which causes significant losses. The aims of this study were to determine the composition and diversity of yeasts on plants of the Brazilian Cerrado and to explore their potential for inhibiting citrus green mould. Leaves and fruit of Byrsonima crassifolia and Eugenia dysenterica were collected from Cerrado conservation areas, and thirty-five yeasts were isolated and identified by sequencing the D1-D2 domain of the rDNA large subunit (26S). The isolates represented the Aureobasidium, Meyerozyma, Candida, and Pichia genera. Three isolates identified as Aureobasidium pullulans exhibited potential for the control of P. digitatum in both in vitro and in vivo tests; these isolates reduced the incidence of disease and increased the storage time of fruit. Aureobasidium. pullulans has immense potential for the biological control of filamentous fungi.

  12. From biocontrol to cancer, probiotics and beyond.

    PubMed

    Dunne, Colum

    2013-01-01

    This invited commentary covers the period 1997-2012 and has seen changes in terminology that progressed from "basic" and "applied" to "translational" research. In the context of Bioengineered, these changes map readily onto the processes of identifying microbial characteristics appropriate for specific applications, isolation of suitable cultures, strain or genome manipulation and exploitation of these or their metabolomes across a range of settings.   To a great degree, this commentary and my career reflect an engagement with molecular microbiology and the trialling of bacteria and derived constructs in applications ranging from intensive-scale crop protection to amelioration of gastrointestinal disease. This engagement began with laboratory and field evaluations of biocontrol, specifically use of pseudomonads effective against nematode and fungal plant pathogens, characterization of mechanisms mediating beneficial effects of probiotic lactobacilli and bifidobacteria and assessment of functional foods in multinational clinical trials relating to inflammatory bowel disease. Subsequent work focused on (1) intellectual property (IP)-based medical devices for localized delivery of systemically toxic and gene cancer therapies; (2) growth of the science base supporting expansion of a multinational business including company acquisitions; (3) complementing existing inter-institutional research capabilities through development of a national industry-led collaboration; and, most recently, (4) strategic research programs at Ireland's newest medical school. My activities as outlined above parallel two distinct aspects of translational research: (1) involvement in knowledge-driven (commercial and research) organizations that brought together necessary resources and infrastructure and (2) availability of scale research funding from European Framework and Irish national programs.

  13. Yeasts and filamentous fungi carried by the gynes of leaf-cutting ants.

    PubMed

    Pagnocca, Fernando C; Rodrigues, André; Nagamoto, Nilson S; Bacci, Maurício

    2008-11-01

    Insect-associated microbes exhibit a wide range of interactions with their hosts. One example of such interactions is the insect-driven dispersal of microorganisms, which plays an essential role in the ecology of several microbes. To study dispersal of microorganisms by leaf-cutting ants (Formicidae: Attini), we applied culture-dependent methods to identify the filamentous fungi and yeasts found in two different body parts of leaf-cutting ant gynes: the exoskeleton and the infrabuccal pocket. The gynes use the latter structure to store a pellet of the ants' symbiotic fungus during nest founding. Many filamentous fungi (n = 142) and yeasts (n = 19) were isolated from the gynes' exoskeleton. In contrast, only seven filamentous fungi and three yeasts isolates were recovered from the infrabuccal pellets, suggesting an efficient mechanism utilized by the gynes to prevent contamination of the symbiotic fungus inoculum. The genus Cladosporium prevailed (78%) among filamentous fungi whereas Aureobasidium, Candida and Cryptococcus prevailed among yeasts associated with gynes. Interestingly, Escovopsis, a specialized fungal pathogen of the leaf-cutting ant-fungus symbiosis, was not isolated from the body parts or from infrabuccal pellets of any gynes sampled. Our results suggest that gynes of the leaf-cutter ants Atta laevigata and A. capiguara do not vertically transmit any particular species of yeasts or filamentous fungi during the foundation of a new nest. Instead, fungi found in association with gynes have a cosmopolitan distribution, suggesting they are probably acquired from the environment and passively dispersed during nest foundation. The possible role of these fungi for the attine ant-microbial symbiosis is discussed.

  14. Multicellular behaviour and production of a wide variety of toxic substances support usage of Bacillus subtilis as a powerful biocontrol agent.

    PubMed

    Nagórska, Krzysztofa; Bikowski, Mariusz; Obuchowski, Michał

    2007-01-01

    Intensive cultivation of plants in the monoculture field system in order to feed the continuously growing human population creates a need for their protection from the variety of natural competitors such as: bacteria, fungi, insects as well as other plants. The increase in the use of chemical substances in the 20th century has brought many effective solutions for the agriculture. However, it was extremely difficult to obtain a substance, which would be directed solely against a specific plant pathogen and would not be harmful for the environment. In the late 1900's scientists began trying to use natural antagonisms between resident soil organism to protect plants. This phenomenon was named biocontrol. Biological control of plants by microorganisms is a very promising alternative to an extended use of pesticides, which are often expensive and accumulate in plants or soil, having adverse effects on humans. Nonpathogenic soil bacteria living in association with roots of higher plants enhance their adaptive potential and, moreover, they can be beneficial for their growth. Here, we present the current status of the use of Bacillus subtilis in biocontrol. This prevalent inhabitant of soil is widely recognized as a powerful biocontrol agent. Naturally present in the immediate vicinity of plant roots, B. subtilis is able to maintain stable contact with higher plants and promote their growth. In addition, due to its broad host range, its ability to form endospores and produce different biologically active compounds with a broad spectrum of activity, B. subtilis as well as other Bacilli are potentially useful as biocontrol agents.

  15. Ecological plasticity of Trichoderma fungi in leached chernozem

    NASA Astrophysics Data System (ADS)

    Svistova, I. D.; Senchakova, T. Yu.

    2010-03-01

    The autecological properties of Trichoderma fungi ecotypes isolated from the leached chernozem of the forest-steppe zone of the European part of Russia have been studied. We were the first who carried out the complex study of the synecological relations of micromycetes of such kinds in a system including the soil, microbial community, and plants, i.e., their relations with soil saprotrophic fungi, bacteria, actinomycetes, plants, and pathogenic fungi. It was shown that the ecological plasticity of the Trichoderma genus in the soil of this zone is determined by its growth rate, the optimum pH and temperature, the biosynthesis of extracellular hydrolytic enzymes, the biological action of mycotoxins, and the ability for parasitism. The efficiency of the introduction of Trichoderma species typical and atypical for the leached chernozem into this soil and their influence on the structure of the microbial community were evaluated. The T. pseudokoningii ecotype, which produces cellulolytic enzymes, is very promising for industrial biotechnology, and the T. harzianum ecotype can be used in soil biotechnology for the biocontrol of chernozem. The addition of a commercial trichodermin preparation into the chernozem damages the structure of its microbial community.

  16. Fungal diversity associated to the olive moth, Prays Oleae bernard: a survey for potential entomopathogenic fungi.

    PubMed

    Oliveira, Ivo; Pereira, José A; Lino-Neto, Teresa; Bento, Albino; Baptista, Paula

    2012-05-01

    Olive production is one of the main agricultural activities in Portugal. In the region of Trás-os-Montes, this crop has been considerably affected by Prays oleae. In order to evaluate the diversity of fungi on Prays oleae population of Trás-os-Montes olive orchards, larvae and pupae of the three annual generations (phyllophagous, antophagous and carpophagous) were collected and evaluated for fungal growth on their surface. From the 3,828 larvae and pupae, a high percentage of individuals exhibited growth of a fungal agent (40.6%), particularly those from the phyllophagous generation. From all the moth generations, a total of 43 species from 24 genera were identified, but the diversity and abundance of fungal species differed between the three generations. Higher diversity was found in the carpophagous generation, followed by the antophagous and phyllophagous generations. The presence of fungi displaying entomopathogenic features was highest in the phyllophagous larvae and pupae, with Beauveria bassiana as the most abundant taxa. The first report of Beauveria bassiana presence on Prays oleae could open new strategies for the biocontrol of this major pest in olive groves since the use of an already adapted species increases the guarantee of success of a biocontrol approach. The identification of antagonistic fungi able to control agents that cause major olive diseases, such as Verticillium dahliae, will benefit future biological control approaches for limiting this increasingly spreading pathogen.

  17. Looking Southeast from Second Floor Mezzanine of Pellet Plant to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Southeast from Second Floor Mezzanine of Pellet Plant to Erbia Mixing Area and Poreformer and Acrawax Mixing Station - Hematite Fuel Fabrication Facility, Pellet Plant, 3300 State Road P, Festus, Jefferson County, MO

  18. Looking East on Third Floor of Pellet Plant Including Tops ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking East on Third Floor of Pellet Plant Including Tops of Line One and Blenders One, Two, and Three - Hematite Fuel Fabrication Facility, Pellet Plant, 3300 State Road P, Festus, Jefferson County, MO

  19. Effect of ingredients and processing parameters on pellet quality.

    PubMed

    Briggs, J L; Maier, D E; Watkins, B A; Behnke, K C

    1999-10-01

    Rations containing varying ratios of corn, high-oil corn, soybean meal, and mechanically expelled soybean meal were pelleted. The effects of ingredients, conditioning steam pressure, and mixing paddle configuration inside the conditioner on pellet quality were investigated. Ration ingredients strongly affected pellet quality. Increasing the protein content increased the pellet durability, whereas increasing the oil content above 7.5% greatly decreased pellet durability. High-oil corn and mechanically expelled soybean meal produced acceptable pellets when combined with soybean meal and regular corn, respectively. However, poor pellet quality resulted when rations containing high-oil corn and mechanically expelled soybean meal were processed. Increasing the residence time in the conditioner by changing mixing paddle pitch resulted in an average 4.5-point increase in pellet durability indices among 65:35 (wt) corn:soybean meal and 65:35 high-oil corn:soybean meal rations.

  20. 3. INTERIOR VIEW OF PELLETIZER BUILDING, BALLING DRUM (UPPER RIGHT) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. INTERIOR VIEW OF PELLETIZER BUILDING, BALLING DRUM (UPPER RIGHT) AND FURNACE (LOWER LEFT), LOOKING EAST - Mesabi Iron Company, Magnetic Concentration Plant, Pelletizer Building, Babbitt, St. Louis County, MN

  1. Pure crystalline estradiol pellet implantation for contraception.

    PubMed

    Asch, R H; Greenblatt, R B; Mahesh, V B

    1978-01-01

    The subcutaneous implantation of estradiol pellets was found to be a simple and effective contraceptive method with good patient acceptance and minimal untoward effects. The pellets (25 mg each) were implanted through a Kearn's trocar into the abdominal wall, 2.5 to 5 cm above and parallel to Poupart's ligament. The regimen began with four pellets, and the dose was maintained or decreased by one pellet every 6 months (four, three, two, one). A potent progestogen was utilized monthly for induction of withdrawal bleeding. Altogether, 236 patients were followed for a total of 1,060 courses in 6,360 cycles (489,02 woman-years). Two pregnancies occurred during therapy. Pearl's index was 0.37. No significant alterations occurred in body weight and blood pressure. Glucose tolerance test, standard blood profiles, and Papanicolaou smears were normal during therapy. No cases of thrombophlebitis, blurred vision, headaches, gastric symptoms, or amenorrhea-galactorrhea were observed. The suppression of ovulation was confirmed by endometrial biopsies, basal body temperature, and serum follicle-stimulating hormone, luteinizing hormone, estradiol, and progesterone in a selected group of patients.

  2. Hardwood control using pelleted herbicides and burning

    Treesearch

    James H. Miller

    1982-01-01

    Treatments using combinations of pelletized herbicides with prescribe burning were tested for planting site preparation on steep terrain (>35% slopes) in the Alabama Piedmont. Mixed forests of southern pines, oaks, and hickories occupied areas before logging. Three burning treatments (no-burn, pre- and post-harvest) were applied randomly among three 4-acre major...

  3. The Manufacturing Process of Bamboo Pellets

    Treesearch

    Zhijia Liu; Zehui Jiang; Zhiyong Cai; Benhua Fei; Xing' e Liu

    2012-01-01

    Bamboo was a kind of biomass materials and had great potential as a bio-energy resource of the future in China. The physical and combustion properties of bamboo pellets were determined and the effects of moisture content (MC) and sizes of particle on these properties were investigated in this research. The results showed that MC and sizes of particle affected these...

  4. At a Glance – Pelleting of DDGS

    USDA-ARS?s Scientific Manuscript database

    NCARL is proud of its active partnership among industry, academic, and extension specialists, and we continue to pursue improved uses and values for distillers grain. We aim to augment both the livestock industry as well as fuel ethanol manufacturers with our research programs. Pelleting is one wa...

  5. Adaptive Immunity to Fungi

    PubMed Central

    Wüthrich, Marcel; Deepe, George S.; Klein, Bruce

    2013-01-01

    Only a handful of the more than 100,000 fungal species on our planet cause disease in humans, yet the number of life-threatening fungal infections in patients has recently skyrocketed as a result of advances in medical care that often suppress immunity intensely. This emerging crisis has created pressing needs to clarify immune defense mechanisms against fungi, with the ultimate goal of therapeutic applications. Herein, we describe recent insights in understanding the mammalian immune defenses deployed against pathogenic fungi. The review focuses on adaptive immune responses to the major medically important fungi and emphasizes how dendritic cells and subsets in various anatomic compartments respond to fungi, recognize their molecular patterns, and signal responses that nurture and shape the differentiation of T cell subsets and B cells. Also emphasized is how the latter deploy effector and regulatory mechanisms that eliminate these nasty invaders while also constraining collateral damage to vital tissue. PMID:22224780

  6. The role of initial spore adhesion in pellet and biofilm formation in Aspergillus niger.

    PubMed

    Priegnitz, Bert-Ewald; Wargenau, Andreas; Brandt, Ulrike; Rohde, Manfred; Dietrich, Sylvia; Kwade, Arno; Krull, Rainer; Fleissner, André

    2012-01-01

    Fungi grow on a great variety of organic and inorganic materials. Colony establishment and growth on solid surfaces require adhesion of spores and hyphae to the substrate, while cell-to-cell interactions among spores and/or hyphae are a prerequisite for the development of three-dimensional mycelial structures such as pellets or biofilms. Surface adherence has been described as a two-step process, comprised of the initial attachment of ungerminated conidia followed by further adhesion of the forming germ tubes and growing hyphae. In the present study, we analyzed the contribution of adhesion of ungerminated spores to pellet and biofilm formation in Aspergillus niger. Mutants deficient in melanin biosynthesis were constructed by the deletion of the alb1 gene, encoding a polyketide synthase essential for pigment biosynthesis. Δalb1 conidia have an altered surface structure and changed physicochemical surface properties. Spore aggregation in liquid culture as well as spore surface attachment differ between the wild type and the mutant in a pH-dependent manner. In liquid culture further pellet formation is unaffected by altered spore-spore interactions, indicating that germ tube and hyphal adherence can compensate for deficiencies in the initial step of spore attachment. In contrast, under conditions promoting adhesion of Δalb1 conidia to polymer surfaces the mutant forms more stable biofilms than the wild type, suggesting that initial spore adhesion supports sessile growth.

  7. Pathology smorgasboard: Biocontrol, pathogen movement, and recent fumigation results.

    USDA-ARS?s Scientific Manuscript database

    Research on soilborne pathogens, disease control, and new forest diseases of interest were presented at the Western Forest and Conservation Nursery Association meeting in 2016. Research topics included reduced-rate soil fumigation, Pythium diversity and biocontrol, pathogen movement among nurseries,...

  8. Challenges and opportunities for the commercialization of postharvest biocontrol

    USDA-ARS?s Scientific Manuscript database

    The past twenty years has seen the field of postharvest biocontrol evolve into a sophisticated science with global research programs worldwide, numerous yearly publications, patented technologies, and the development of new commercial products. The use of these products, however, still remains limi...

  9. Screening mycotoxins for quorum inhibition in a biocontrol bacterial endophyte

    USDA-ARS?s Scientific Manuscript database

    Bacterial endophytes are used as biocontrol organisms for plant pathogens such as the maize endophyte Fusarium verticillioides and its production of fumonisin mycotoxins. However, such applications are not always predictable and efficient. Bacteria communicate via cell-dependent signals, which are r...

  10. Metacridamides A and B from the biocontrol fungus metarhizium acridum

    USDA-ARS?s Scientific Manuscript database

    Metarhizium acridum, an entomopathogenic fungus, has been commercialized and used successfully for biocontrol of grasshopper pests in Africa and Australia. As part of an effort to catalog the secondary metabolites of this fungus we discovered that its conidia produce two novel 17-membered macrocycl...

  11. Grouper as a natural biocontrol of invasive lionfish.

    PubMed

    Mumby, Peter J; Harborne, Alastair R; Brumbaugh, Daniel R

    2011-01-01

    Lionfish (Pterois volitans/miles) have invaded the majority of the Caribbean region within five years. As voracious predators of native fishes with a broad habitat distribution, lionfish are poised to cause an unprecedented disruption to coral reef diversity and function. Controls of lionfish densities within its native range are poorly understood, but they have been recorded in the stomachs of large-bodied Caribbean groupers. Whether grouper predation of lionfish is sufficient to act as a biocontrol of the invasive species is unknown, but pest biocontrol by predatory fishes has been reported in other ecosystems. Groupers were surveyed along a chain of Bahamian reefs, including one of the region's most successful marine reserves which supports the top one percentile of Caribbean grouper biomass. Lionfish biomass exhibited a 7-fold and non-linear reduction in relation to the biomass of grouper. While Caribbean grouper appear to be a biocontrol of invasive lionfish, the overexploitation of their populations by fishers, means that their median biomass on Caribbean reefs is an order of magnitude less than in our study. Thus, chronic overfishing will probably prevent natural biocontrol of lionfishes in the Caribbean.

  12. Grouper as a Natural Biocontrol of Invasive Lionfish

    PubMed Central

    Mumby, Peter J.; Harborne, Alastair R.; Brumbaugh, Daniel R.

    2011-01-01

    Lionfish (Pterois volitans/miles) have invaded the majority of the Caribbean region within five years. As voracious predators of native fishes with a broad habitat distribution, lionfish are poised to cause an unprecedented disruption to coral reef diversity and function. Controls of lionfish densities within its native range are poorly understood, but they have been recorded in the stomachs of large-bodied Caribbean groupers. Whether grouper predation of lionfish is sufficient to act as a biocontrol of the invasive species is unknown, but pest biocontrol by predatory fishes has been reported in other ecosystems. Groupers were surveyed along a chain of Bahamian reefs, including one of the region's most successful marine reserves which supports the top one percentile of Caribbean grouper biomass. Lionfish biomass exhibited a 7-fold and non-linear reduction in relation to the biomass of grouper. While Caribbean grouper appear to be a biocontrol of invasive lionfish, the overexploitation of their populations by fishers, means that their median biomass on Caribbean reefs is an order of magnitude less than in our study. Thus, chronic overfishing will probably prevent natural biocontrol of lionfishes in the Caribbean. PMID:21731769

  13. Weed biocontrol in the EU: from serendipity to strategy

    USDA-ARS?s Scientific Manuscript database

    Biological control of weeds is a globally-recognized approach to the management of the worst invasive plants in the world. Unfortunately, accidental introduction of agents account for most weed biocontrol in the EU, but do include a number of current or emerging successes. From the redistribution of...

  14. Endophytic fungal diversity in Theobroma cacao (cacao) and T. grandiflorum (cupuaçu) trees and their potential for growth promotion and biocontrol of black-pod disease.

    PubMed

    Hanada, Rogério Eiji; Pomella, Alan William V; Costa, Heron Salazar; Bezerra, José Luiz; Loguercio, Leandro L; Pereira, José O

    2010-01-01

    The endophytic niches of plants are a rich source of microbes that can directly and indirectly promote plant protection, growth and development. The diversity of culturable endophytic fungi from stems and branches of Theobroma cacao (cacao) and Theobroma grandiflorum (cupuaçu) trees growing in the Amazon region of Brazil was assessed. The collection of fungal endophytic isolates obtained was applied in field experiments to evaluate their potential as biocontrol agents against Phytophthora palmivora, the causal agent of the black-pod rot disease of cacao, one of the most important pathogens in cocoa-producing regions worldwide. The isolated endophytic fungi from 60 traditional, farmer-planted, healthy cacao and 10 cupuaçu plants were cultured in PDA under conditions inducing sporulation. Isolates were classified based upon the morphological characteristics of their cultures and reproductive structures. Spore suspensions from a total of 103 isolates that could be classified at least up to genus level were tested against P. palmivora in pods attached to cacao trees in the field. Results indicated that ∼70% of isolates showed biocontrol effects to a certain extent, suggesting that culturable endophytic fungal biodiversity in this system is of a mostly mutualistic type of interaction with the host. Eight isolates from genera Trichoderma (reference isolate), Pestalotiopsis, Curvularia, Tolypocladium and Fusarium showed the highest level of activity against the pathogen, and were further characterized. All demonstrated their endophytic nature by colonizing axenic cacao plantlets, and confirmed their biocontrol activity on attached pods trials by showing significant decrease in disease severity in relation to the positive control. None, however, showed detectable growth-promotion effects. Aspects related to endophytic biodiversity and host-pathogen-endophyte interactions in the environment of this study were discussed on the context of developing sustainable strategies

  15. Clonal reproduction in fungi.

    PubMed

    Taylor, John W; Hann-Soden, Christopher; Branco, Sara; Sylvain, Iman; Ellison, Christopher E

    2015-07-21

    Research over the past two decades shows that both recombination and clonality are likely to contribute to the reproduction of all fungi. This view of fungi is different from the historical and still commonly held view that a large fraction of fungi are exclusively clonal and that some fungi have been exclusively clonal for hundreds of millions of years. Here, we first will consider how these two historical views have changed. Then we will examine the impact on fungal research of the concept of restrained recombination [Tibayrenc M, Ayala FJ (2012) Proc Natl Acad Sci USA 109 (48):E3305-E3313]. Using animal and human pathogenic fungi, we examine extrinsic restraints on recombination associated with bottlenecks in genetic variation caused by geographic dispersal and extrinsic restraints caused by shifts in reproductive mode associated with either disease transmission or hybridization. Using species of the model yeast Saccharomyces and the model filamentous fungus Neurospora, we examine intrinsic restraints on recombination associated with mating systems that range from strictly clonal at one extreme to fully outbreeding at the other and those that lie between, including selfing and inbreeding. We also consider the effect of nomenclature on perception of reproductive mode and a means of comparing the relative impact of clonality and recombination on fungal populations. Last, we consider a recent hypothesis suggesting that fungi thought to have the most severe intrinsic constraints on recombination actually may have the fewest.

  16. Clonal reproduction in fungi

    PubMed Central

    Taylor, John W.; Hann-Soden, Christopher; Branco, Sara; Sylvain, Iman; Ellison, Christopher E.

    2015-01-01

    Research over the past two decades shows that both recombination and clonality are likely to contribute to the reproduction of all fungi. This view of fungi is different from the historical and still commonly held view that a large fraction of fungi are exclusively clonal and that some fungi have been exclusively clonal for hundreds of millions of years. Here, we first will consider how these two historical views have changed. Then we will examine the impact on fungal research of the concept of restrained recombination [Tibayrenc M, Ayala FJ (2012) Proc Natl Acad Sci USA 109 (48):E3305–E3313]. Using animal and human pathogenic fungi, we examine extrinsic restraints on recombination associated with bottlenecks in genetic variation caused by geographic dispersal and extrinsic restraints caused by shifts in reproductive mode associated with either disease transmission or hybridization. Using species of the model yeast Saccharomyces and the model filamentous fungus Neurospora, we examine intrinsic restraints on recombination associated with mating systems that range from strictly clonal at one extreme to fully outbreeding at the other and those that lie between, including selfing and inbreeding. We also consider the effect of nomenclature on perception of reproductive mode and a means of comparing the relative impact of clonality and recombination on fungal populations. Last, we consider a recent hypothesis suggesting that fungi thought to have the most severe intrinsic constraints on recombination actually may have the fewest. PMID:26195774

  17. Feeding horses with industrially manufactured pellets with fungal spores to promote nematode integrated control.

    PubMed

    Hernández, José Ángel; Arroyo, Fabián Leonardo; Suárez, José; Cazapal-Monteiro, Cristiana Filipa; Romasanta, Ángel; López-Arellano, María Eugenia; Pedreira, José; de Carvalho, Luis Manuel Madeira; Sánchez-Andrade, Rita; Arias, María Sol; de Gives, Pedro Mendoza; Paz-Silva, Adolfo

    2016-10-15

    The usefulness of pellets industrially manufactured with spores of parasiticide fungi as a contribution to integrated nematode control was assessed in grazing horses throughout sixteen months. Two groups of 7 Pura Raza Galega autochthonous horses (G-T and G-P) were dewormed pour-on (1mg Ivermectin/kg bw) at the beginning of the trial, and other group (G-C) remained untreated. The G-P was provided daily with commercial pellets to which was added a mixture of fungal spores during the industrial manufacturing (2×10(6) spores of Mucor circinelloides and same dose of Duddingtonia flagrans/kg), and G-T and G-C received pellets without spores. The efficacy of the parasiticidal strategy was assessed by estimating the reduction in the faecal egg counts (FECR) and in the number of horses shedding eggs in the faeces (PHR), and also the egg reappearance periods (ERP). Blood analyses were performed to identify the changes in the red and white cell patterns. To ascertain if horses developed an IgG humoral response against the fungi, antigenic products collected from M. circinelloides and D. flagrans were exposed to the horse sera by using an ELISA. The faecal elimination of eggs of Parascaris equorum and strongyles ceased 2 weeks after treatment in G-T and G-P, thus the values of FECR and PHR were 100%. No P. equorum-eggs were detected later, and the strongyle egg reappearance period was 28 weeks in G-P, and 8 weeks in G-T. Strongyle egg-output values remained lower than 300 eggs per gram of faeces in the G-P, whereas numbers between 330 and 772 in G-C and G-T were recorded. Normal values for the erythrocytes, haemoglobin and haematocrit in horses consuming pellets with spores were recorded, and lower than normal in the other groups. Sensitization of horses to the fungal species was disproven. It is concluded that feeding horses with pellets industrially manufactured with fungal spores represents a very useful tool to implement an integrated control of helminths affecting

  18. Dielectric Properties of Peanut-hull Pellets at Microwave Frequencies

    USDA-ARS?s Scientific Manuscript database

    Peanut-hull pellets are obtained from a waste product, peanut-hulls, which after pelleting can have several uses, namely as a renewable fuel. Rapid and nondestructive characterization of peanut-hull pellets is important for industrial utilization of this resource. Properties such as water content an...

  19. Owl Pellet Analysis--A Useful Tool in Field Studies

    ERIC Educational Resources Information Center

    Medlin, G. C.

    1977-01-01

    Describes a technique by which the density and hunting habits of owls can be inferred from their pellets. Owl pellets--usually small, cylindrical packages of undigested bone, hair, etc.--are regurgitated by a roosting bird. A series of activities based on owl pellets are provided. (CP)

  20. Effects of carbonization conditions on properties of bamboo pellets

    Treesearch

    Zhijia Liu; Zehui Jiang; Zhiyong Cai; Benhua Fei; Yan Yu; Xing' e Liu

    2013-01-01

    Bamboo is a biomass material and has great potential as a bio-energy resource of the future in China. Bamboo pellets were successfully manufactured using a laboratory pellet mill in preliminary work. This study was therefore carried out to investigate the effect of carbonization conditions (temperature and time) on properties of bamboo pellets and to evaluate product...

  1. Owl Pellet Analysis--A Useful Tool in Field Studies

    ERIC Educational Resources Information Center

    Medlin, G. C.

    1977-01-01

    Describes a technique by which the density and hunting habits of owls can be inferred from their pellets. Owl pellets--usually small, cylindrical packages of undigested bone, hair, etc.--are regurgitated by a roosting bird. A series of activities based on owl pellets are provided. (CP)

  2. Direct plantlet inoculation with soil or insect-associated fungi may control cabbage root fly maggots.

    PubMed

    Razinger, Jaka; Lutz, Matthias; Schroers, Hans-Josef; Palmisano, Marilena; Wohler, Christian; Urek, Gregor; Grunder, Jürg

    2014-07-01

    A potential Delia radicum biological control strategy involving cauliflower plantlet inoculation with various fungi was investigated in a series of laboratory and glasshouse experiments. In addition to entomopathogenic fungi, fungi with a high rhizosphere competence and fungi with the ability to survive as saprotrophs in soil were tested. The following fungal species were evaluated in the experiments: Trichoderma atroviride, T. koningiopsis, T. gamsii, Beauveria bassiana, Metharhizium anisopliae, M. brunneum and Clonostachys solani. A commercial carbosulfan-based insecticide was used as a positive control. Additionally, two commercial products, one based on B. bassiana (Naturalis) and one on Bacillus thuringiensis (Delfin) were used as reference biocontrol agents. The aims were (i) to assess the pathogenicity of the selected fungal isolates to Delia radicum, (ii) to evaluate the fungal isolates' rhizosphere competence, with the emphasis on the persistence of the original inoculum on the growing roots, (iii) to assess possible endophytic plant tissue colonization, and (iv) to evaluate potential plant growth stimulating effects of the added inoculi. Significant pathogenicity of tested fungi against Delia radicum was confirmed in in vitro and glasshouse experiments. All tested fungi persisted on cauliflower rhizoplane. More importantly, the added fungi were found on thoroughly washed roots outside the original point of inoculation. This provided us with evidence that our tested fungi could be transferred via or grow with the elongating roots. In addition to colonizing the rhizoplane, some fungi were found inside the plant root or stem tissue, thus exhibiting endophytic characteristics. The importance of fungal ecology as a criterion in appropriate biological control agent selection is discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Desirable Traits of a Good Biocontrol Agent against Verticillium Wilt.

    PubMed

    Deketelaere, Silke; Tyvaert, Lien; França, Soraya C; Höfte, Monica

    2017-01-01

    The soil-borne fungus Verticillium causes serious vascular disease in a wide variety of annual crops and woody perennials. Verticillium wilt is notoriously difficult to control by conventional methods, so there is great potential for biocontrol to manage this disease. In this study we aimed to review the research about Verticillium biocontrol to get a better understanding of characteristics that are desirable in a biocontrol agent (BCA) against Verticillium wilt. We only considered studies in which the BCAs were tested on plants. Most biocontrol studies were focused on plants of the Solanaceae, Malvaceae, and Brassicaceae and within these families eggplant, cotton, and oilseed rape were the most studied crops. The list of bacterial BCAs with potential against Verticillium was dominated by endophytic Bacillus and Pseudomonas isolates, while non-pathogenic xylem-colonizing Verticillium and Fusarium isolates topped the fungal list. Predominant modes of action involved in biocontrol were inhibition of primary inoculum germination, plant growth promotion, competition and induced resistance. Many BCAs showed in vitro antibiosis and mycoparasitism but these traits were not correlated with activity in vivo and there is no evidence that they play a role in planta. Good BCAs were obtained from soils suppressive to Verticillium wilt, disease suppressive composts, and healthy plants in infested fields. Desirable characteristics in a BCA against Verticillium are the ability to (1) affect the survival or germination of microsclerotia, (2) colonize the xylem and/or cortex and compete with the pathogen for nutrients and/or space, (3) induce resistance responses in the plant and/or (4) promote plant growth. Potential BCAs should be screened in conditions that resemble the field situation to increase the chance of successful use in practice. Furthermore, issues such as large scale production, formulation, preservation conditions, shelf life, and application methods should be

  4. Desirable Traits of a Good Biocontrol Agent against Verticillium Wilt

    PubMed Central

    Deketelaere, Silke; Tyvaert, Lien; França, Soraya C.; Höfte, Monica

    2017-01-01

    The soil-borne fungus Verticillium causes serious vascular disease in a wide variety of annual crops and woody perennials. Verticillium wilt is notoriously difficult to control by conventional methods, so there is great potential for biocontrol to manage this disease. In this study we aimed to review the research about Verticillium biocontrol to get a better understanding of characteristics that are desirable in a biocontrol agent (BCA) against Verticillium wilt. We only considered studies in which the BCAs were tested on plants. Most biocontrol studies were focused on plants of the Solanaceae, Malvaceae, and Brassicaceae and within these families eggplant, cotton, and oilseed rape were the most studied crops. The list of bacterial BCAs with potential against Verticillium was dominated by endophytic Bacillus and Pseudomonas isolates, while non-pathogenic xylem-colonizing Verticillium and Fusarium isolates topped the fungal list. Predominant modes of action involved in biocontrol were inhibition of primary inoculum germination, plant growth promotion, competition and induced resistance. Many BCAs showed in vitro antibiosis and mycoparasitism but these traits were not correlated with activity in vivo and there is no evidence that they play a role in planta. Good BCAs were obtained from soils suppressive to Verticillium wilt, disease suppressive composts, and healthy plants in infested fields. Desirable characteristics in a BCA against Verticillium are the ability to (1) affect the survival or germination of microsclerotia, (2) colonize the xylem and/or cortex and compete with the pathogen for nutrients and/or space, (3) induce resistance responses in the plant and/or (4) promote plant growth. Potential BCAs should be screened in conditions that resemble the field situation to increase the chance of successful use in practice. Furthermore, issues such as large scale production, formulation, preservation conditions, shelf life, and application methods should be

  5. Modeling Dynamic Fracture of Cryogenic Pellets

    SciTech Connect

    Parks, Paul

    2016-06-30

    This work is part of an investigation with the long-range objective of predicting the size distribution function and velocity dispersion of shattered pellet fragments after a large cryogenic pellet impacts a solid surface at high velocity. The study is vitally important for the shattered pellet injection (SPI) technique, one of the leading technologies being implemented at ORNL for the mitigation of disruption damage on current tokamaks and ITER. The report contains three parts that are somewhat interwoven. In Part I we formulated a self-similar model for the expansion dynamics and velocity dispersion of the debris cloud following pellet impact against a thick (rigid) target plate. Also presented in Part I is an analytical fracture model that predicts the nominal or mean size of the fragments in the debris cloud and agrees well with known SPI data. The aim of Part II is to gain an understanding of the pellet fracturing process when a pellet is shattered inside a miter tube with a sharp bend. Because miter tubes have a thin stainless steel (SS) wall a permanent deformation (dishing) of the wall is produced at the site of the impact. A review of the literature indicates that most projectile impact on thin plates are those for which the target is deformed and the projectile is perfectly rigid. Such impacts result in “projectile embedding” where the projectile speed is reduced to zero during the interaction so that all the kinetic energy (KE) of the projectile goes into the energy stored in plastic deformation. Much of the literature deals with perforation of the target. The problem here is quite different; the softer pellet easily undergoes complete material failure causing only a small transfer of KE to stored energy of wall deformation. For the real miter tube, we derived a strain energy function for the wall deflection using a non-linear (plastic) stress-strain relation for 304 SS. Using a dishing profile identical to the linear Kirchkoff-Love profile (for lack

  6. Fuel Pellets from Wheat Straw: The Effect of Lignin Glass Transition and Surface Waxes on Pelletizing Properties

    Treesearch

    Wolfgang Stelte; Craig Clemons; Jens K. Holm; Jesper Ahrenfeldt; Ulrik B. Henriksen; Anand R. Sanadi

    2012-01-01

    The utilization of wheat straw as a renewable energy resource is limited due to its low bulk density. Pelletizing wheat straw into fuel pellets of high density increases its handling properties but is more challenging compared to pelletizing wood biomass. Straw has a lower lignin content and a high concentration of hydrophobic waxes on its outer surface that may limit...

  7. Biocontrol agent Bacillus amyloliquefaciens LJ02 induces systemic resistance against cucurbits powdery mildew

    PubMed Central

    Li, Yunlong; Gu, Yilin; Li, Juan; Xu, Mingzhu; Wei, Qing; Wang, Yuanhong

    2015-01-01

    Powdery mildew is a fungal disease found in a wide range of plants and can significantly reduce crop yields. Bacterial strain LJ02 is a biocontrol agent (BCA) isolated from a greenhouse in Tianjin, China. In combination of morphological, physiological, biochemical and phylogenetic analyses, strain LJ02 was classified as a new member of Bacillus amyloliquefaciens. Greenhouse trials showed that LJ02 fermentation broth (LJ02FB) can effectively diminish the occurrence of cucurbits powdery mildew. When treated with LJ02FB, cucumber seedlings produced significantly elevated production of superoxide dismutase, peroxidase, polyphenol oxidase and phenylalanine ammonia lyase as compared to that of the control. We further confirmed that the production of free salicylic acid (SA) and expression of one pathogenesis-related (PR) gene PR-1 in cucumber leaves were markedly elevated after treating with LJ02FB, suggesting that SA-mediated defense response was stimulated. Moreover, LJ02FB-treated cucumber leaves could secrete resistance-related substances into rhizosphere that inhibit the germination of fungi spores and the growth of pathogens. Finally, we separated bacterium and its fermented substances to test their respective effects and found that both components have SA-inducing activity and bacterium plays major roles. Altogether, we identified a BCA against powdery mildew and its mode of action by inducing systemic resistance such as SA signaling pathway. PMID:26379654

  8. AMF-induced biocontrol against plant parasitic nematodes in Musa sp.: a systemic effect.

    PubMed

    Elsen, A; Gervacio, D; Swennen, R; De Waele, D

    2008-07-01

    Although mycorrhizal colonization provides a bioprotectional effect against a broad range of soil-borne pathogens, including plant parasitic nematodes, the commercial use of arbuscular mycorrhizal fungi (AMF) as biocontrol agents is still in its infancy. One of the main reasons is the poor understanding of the modes of action. Most AMF mode of action studies focused on AMF-bacterial/fungal pathogens. Only few studies so far examined AMF-plant parasitic nematode interactions. Therefore, the aim of the study was to determine whether the AMF Glomus intraradices was able to incite systemic resistance in banana plants towards Radopholus similis and Pratylenchus coffeae, two plant parasitic nematodes using a split-root compartmental set-up. The AMF reduced both nematode species by more than 50%, even when the AMF and the plant parasitic nematodes were spatially separated. The results obtained demonstrate for the first time that AMF have the ability to induce systemic resistance against plant parasitic nematodes in a root system.

  9. Transcriptomic response of Arabidopsis thaliana after 24 h incubation with the biocontrol fungus Trichoderma harzianum.

    PubMed

    Morán-Diez, Eugenia; Rubio, Belén; Domínguez, Sara; Hermosa, Rosa; Monte, Enrique; Nicolás, Carlos

    2012-04-15

    Trichoderma harzianum is a fungus used as biocontrol agent using its antagonistic abilities against phytopathogenic fungi, although it has also direct effects on plants, increasing or accelerating their growth and resistance to diseases and the tolerance to abiotic stresses. We analyzed Arabidopsis thaliana gene expression changes after 24 h of incubation in the presence of T. harzianum T34 using the Affymetrix GeneChip Arabidopsis ATH1. Because this microarray contains more than 22,500 probe sets representing approximately 24,000 genes, we were able to construct a global picture of the molecular physiology of the plant at 24 h of T. harzianum-Arabidopsis interaction. We identified several differentially expressed genes that are involved in plant responses to stress, regulation of transcription, signal transduction or plant metabolism. Our data support the hypothesis that salicylic acid- and jasmonic acid-related genes were down-regulated in A. thaliana after 24 h of incubation in the presence of T. harzianum T34, while several genes related to abiotic stress responses were up-regulated. These systemic changes elicited by T. harzianum in Arabidopsis are discussed.

  10. Candida parapsilosis as a Potent Biocontrol Agent against Growth and Aflatoxin Production by Aspergillus Species

    PubMed Central

    Niknejad, F; Zaini, F; Faramarzi, MA; Amini, M; Kordbacheh, P; Mahmoudi, M; Safara, M

    2012-01-01

    Background: Aflatoxin contamination of food and feed stuff is a serious health problem and significant economic concerns. In the present study, the inhibitory effect of Candida parapsilosis IP1698 on mycelial growth and aflatoxin production in aflatoxigenic strains of Aspergillus species was investigated. Methods: Mycelial growth inhibitions of nine strains of aflatoxigenic and non-aflatoxigenic Aspergillus species in the presence of C. parapsilosis investigated by pour plate technique at different pH, temperature and time of incubation. Reduction of aflatoxin was evaluated in co-cultured fungi in yeast extract sucrose broth after seven days of incubation using HPLC method. The data were analyzed by SPSS 11.5. Results: The presence of the C. parapsilosis at different pH did not affect significantly the growth rate of Aspergillus isolates. On the other hand, temperature and time of incubation showed to be significantly effective when compared to controls without C. parapsilosis (P≤0.05). In aflatoxigenic strains, minimum percentage of reductions in total aflatoxin and B1, B2, G1, G2 fractions were 92.98, 92.54, 77.48, 54.54 and 72.22 and maximum percentage of reductions were 99.59, not detectable, 94.42, and not detectable in both G1 and G2, respectively. Conclusion: C. parapsilosis might employ as a good biocontrol agent against growth and aflatoxin production by aflatoxigenic Aspergillus species PMID:23308351

  11. Safety and regulation of yeasts used for biocontrol or biopreservation in the food or feed chain.

    PubMed

    Sundh, Ingvar; Melin, Petter

    2011-01-01

    Yeasts have been important components of spontaneous fermentations in food and beverage processing for millennia. More recently, the potential of utilising antagonistic yeasts, e.g. Pichia anomala and Candida spp., for post-harvest biological control of spoilage fungi during storage of plant-derived produce ('biopreservation') has been clearly demonstrated. Although some yeast species are among the safest microorganisms known, several have been reported in opportunistic infections in humans, including P. anomala and bakers' yeast, Saccharomyces cerevisiae. More research is needed about the dominant pathogenicity and virulence factors in opportunistic yeasts, and whether increased utilisation of biopreservative yeasts in general could contribute to an increased prevalence of yeast infections. The regulatory situation for yeasts used in post-harvest biocontrol is complex and the few products that have reached the market are mainly registered as biological pesticides. The qualified presumption of safety (QPS) approach to safety assessments of microorganisms intentionally added to food or feed, recently launched by the European Food Safety Authority, can lead to more efficient evaluations of new products containing microbial species with a sufficient body of knowledge or long-term experience on their safety. P. anomala is one of several yeast species that have been given QPS status, although the status is restricted to use of this yeast for enzyme and metabolite production purposes. With regard to authorisation of new biopreservative yeasts, we recommend that the possibility to regulate microorganisms for food biopreservation as food additives be considered.

  12. Biocontrol agent Bacillus amyloliquefaciens LJ02 induces systemic resistance against cucurbits powdery mildew.

    PubMed

    Li, Yunlong; Gu, Yilin; Li, Juan; Xu, Mingzhu; Wei, Qing; Wang, Yuanhong

    2015-01-01

    Powdery mildew is a fungal disease found in a wide range of plants and can significantly reduce crop yields. Bacterial strain LJ02 is a biocontrol agent (BCA) isolated from a greenhouse in Tianjin, China. In combination of morphological, physiological, biochemical and phylogenetic analyses, strain LJ02 was classified as a new member of Bacillus amyloliquefaciens. Greenhouse trials showed that LJ02 fermentation broth (LJ02FB) can effectively diminish the occurrence of cucurbits powdery mildew. When treated with LJ02FB, cucumber seedlings produced significantly elevated production of superoxide dismutase, peroxidase, polyphenol oxidase and phenylalanine ammonia lyase as compared to that of the control. We further confirmed that the production of free salicylic acid (SA) and expression of one pathogenesis-related (PR) gene PR-1 in cucumber leaves were markedly elevated after treating with LJ02FB, suggesting that SA-mediated defense response was stimulated. Moreover, LJ02FB-treated cucumber leaves could secrete resistance-related substances into rhizosphere that inhibit the germination of fungi spores and the growth of pathogens. Finally, we separated bacterium and its fermented substances to test their respective effects and found that both components have SA-inducing activity and bacterium plays major roles. Altogether, we identified a BCA against powdery mildew and its mode of action by inducing systemic resistance such as SA signaling pathway.

  13. Simulation of peeling-ballooning modes with pellet injection

    SciTech Connect

    Chen, S. Y.; Huang, J.; Sun, T. T.; Tang, C. J.; Wang, Z. H.

    2014-11-15

    The influence of pellet ablation on the evolution of peeling-ballooning (P-B) modes is studied with BOUT++ code. The atoms coming from pellet ablation can significantly reshape the plasma pressure profile, so the behaviors of P-B modes and edge localized mode (ELM) are modified dramatically. This paper shows that the energy loss associated with an ELM increases substantially over that without the pellet, if the pellet is deposited at the top of the pedestal. On the contrary, for pellet deposition in the middle of the pedestal region the ELM energy loss can be less.

  14. Nuclear fuel pellets fabricated from gel-derived microspheres

    NASA Astrophysics Data System (ADS)

    Matthews, R. B.; Hart, P. E.

    1980-09-01

    UO2 pellets were fabricated from UO3 gel microspheres by a combined gel-sphere/pellet fabrication process. Desirable sphere properties were established; calcining cycles, pressing conditions, and sintering cycles sufficient to fabricate UO2 pellets with densities up to 96% TD were determined. The stoichoimetry, activity, density, size and deformability of the spheres had to be within specific ranges for fabrication of high density, crack-free pellets. Preliminary attempts to fabricate ThO2 and ThO2 -UO2 pellets are also described.

  15. Electromagnetic railgun hydrogen pellet injector: Progress and prospect

    SciTech Connect

    Kim, Kyekyoon

    1988-12-01

    A two-stage, fuseless, plasma-arc-driven electromagnetic railgun system suitable for hydrogen pellet acceleration has been developed and successfully tested. The first stage is a combination of a hydrogen pellet generator and a gas gun, which is responsible for injecting a medium-velocity hydrogen pellet into the second-stage railgun through a coupling piece. As the pellet enters the railgun, a specially designed arc-initiation scheme electrically breaks down the propellant gas which has followed the pellet from the gas gun into the railgun, thus forming a conducting plasma-arc armature immediately behind the pellet. This arc formation event coincides with the triggering of the main railgun current and allows the plasma-arc armature to subsequently propel the hydrogen pellet to a high velocity. Using this two-stage acceleration scheme with a 1-m-long railgun barrel, solid hydrogen pellet velocities in excess of 2.2 km/s have been achieved for a pellet 3.2 mm in diameter and 4 mm in length. The objectives of this paper are two-fold: first, a critical review of the achievements thus far on the railgun hydrogen-pellet injector and second, a description of the most recent technological developments and their implications for future work, in particular, the prospect of employing a railgun pellet injector for future large devices. 6 refs., 2 figs., 1 tab.

  16. Nematode-Trapping Fungi.

    PubMed

    Jiang, Xiangzhi; Xiang, Meichun; Liu, Xingzhong

    2017-01-01

    Nematode-trapping fungi are a unique and intriguing group of carnivorous microorganisms that can trap and digest nematodes by means of specialized trapping structures. They can develop diverse trapping devices, such as adhesive hyphae, adhesive knobs, adhesive networks, constricting rings, and nonconstricting rings. Nematode-trapping fungi have been found in all regions of the world, from the tropics to Antarctica, from terrestrial to aquatic ecosystems. They play an important ecological role in regulating nematode dynamics in soil. Molecular phylogenetic studies have shown that the majority of nematode-trapping fungi belong to a monophyletic group in the order Orbiliales (Ascomycota). Nematode-trapping fungi serve as an excellent model system for understanding fungal evolution and interaction between fungi and nematodes. With the development of molecular techniques and genome sequencing, their evolutionary origins and divergence, and the mechanisms underlying fungus-nematode interactions have been well studied. In recent decades, an increasing concern about the environmental hazards of using chemical nematicides has led to the application of these biological control agents as a rapidly developing component of crop protection.

  17. High-rate behaviour of iron ore pellet

    NASA Astrophysics Data System (ADS)

    Gustafsson, Gustaf; Häggblad, Hans-Åke; Jonsén, Pär; Nishida, Masahiro

    2015-09-01

    Iron ore pellets are sintered, centimetre-sized spheres of ore with high iron content. Together with carbonized coal, iron ore pellets are used in the production of steel. In the transportation from the pelletizing plants to the customers, the iron ore pellets are exposed to different loading situations, resulting in degradation of strength and in some cases fragmentation. For future reliable numerical simulations of the handling and transportation of iron ore pellets, knowledge about their mechanical properties is needed. This paper describes the experimental work to investigate the dynamic mechanical properties of blast furnace iron ore pellets. To study the dynamic fracture of iron ore pellets a number of split Hopkinson pressure bar tests are carried out and analysed.

  18. Tritium pellet injection sequences for TFTR

    SciTech Connect

    Houlberg, W.A.; Milora, S.L.; Attenberger, S.E.; Singer, C.E.; Schmidt, G.L.

    1983-01-01

    Tritium pellet injection into neutral deuterium, beam heated deuterium plasmas in the Tokamak Fusion Test Reactor (TFTR) is shown to be an attractive means of (1) minimizing tritium use per tritium discharge and over a sequence of tritium discharges; (2) greatly reducing the tritium load in the walls, limiters, getters, and cryopanels; (3) maintaining or improving instantaneous neutron production (Q); (4) reducing or eliminating deuterium-tritium (D-T) neutron production in non-optimized discharges; and (5) generally adding flexibility to the experimental sequences leading to optimal Q operation. Transport analyses of both compression and full-bore TFTR plasmas are used to support the above observations and to provide the basis for a proposed eight-pellet gas gun injector for the 1986 tritium experiments.

  19. Production of sintered porous metal fluoride pellets

    DOEpatents

    Anderson, L.W.; Stephenson, M.J.

    1973-12-25

    Porous pellets characterized by a moderately reactive crust and a softer core of higher reactivity are produced by forming agglomerates containing a metal fluoride powder and a selected amount ofwater. The metal fluoride is selected to be sinterable and essentially non-reactive with gaseous fluorinating agents. The agglomerates are contacted with a gaseous fluorinating agent under controlled conditions whereby the heat generated by localized reaction of the agent and water is limited to values effccting bonding by localized sintering. Porous pellets composed of cryolite (Na/sub 3/AlF/sub 6/) can be used to selectively remove trace quantities of niobium pentafluoride from a feed gas consisting predominantly of uranium hexafluoride. (Official Gazette)

  20. Optimization of Porous Pellets for Phosphate Recovery ...

    EPA Pesticide Factsheets

    The poster presents the preliminary adsorption experiment showing that phosphate concentration is decreasing over time as well as presenting the kinetics models that best fit the data collected over 25 days. The purpose of this project is to find a better material for adsorption of phosphate from water treatment facilities. The material is made into pellets which allow for adsorption and are easier to remove from the system when capacity is reached.

  1. Plant Pathogenic Fungi.

    PubMed

    Doehlemann, Gunther; Ökmen, Bilal; Zhu, Wenjun; Sharon, Amir

    2017-01-01

    Fungi are among the dominant causal agents of plant diseases. To colonize plants and cause disease, pathogenic fungi use diverse strategies. Some fungi kill their hosts and feed on dead material (necrotrophs), while others colonize the living tissue (biotrophs). For successful invasion of plant organs, pathogenic development is tightly regulated and specialized infection structures are formed. To further colonize hosts and establish disease, fungal pathogens deploy a plethora of virulence factors. Depending on the infection strategy, virulence factors perform different functions. While basically all pathogens interfere with primary plant defense, necrotrophs secrete toxins to kill plant tissue. In contrast, biotrophs utilize effector molecules to suppress plant cell death and manipulate plant metabolism in favor of the pathogen. This article provides an overview of plant pathogenic fungal species and the strategies they use to cause disease.

  2. Mycelial fungi in cryopegs

    NASA Astrophysics Data System (ADS)

    Ozerskaya, S. M.; Ivanushkina, N. E.; Kochkina, G. A.; Fattakhova, R. N.; Gilichinsky, D. A.

    2004-10-01

    Mycelial fungi from cryopegs (tundra, Kolyma lowland, Russia) have been studied. The use of media with different amounts of salt and cultivation at 4 and 25 °C allowed us to isolate filamentous fungi assigned to 11 species. The micromycetes of genus Geomyces were found most often. The total amount of fungi reached 1-4×102 CFU ml[minus sign]1 of water. The extreme conditions of the cryopegs - the high salinity of the water (150-200 g l[minus sign]1) and the constant low temperatures (average annual temperature is from [minus sign]9 to [minus sign]11 °C) - might serve as a model for the conditions of interplanetary environments.

  3. Cytochromes of Aquatic Fungi

    PubMed Central

    Gleason, Frank H.; Unestam, Torgny

    1968-01-01

    The cytochrome systems of two classes of aquatic fungi, the Oomycetes and Chytridiomycetes, were studied by means of reduced-minus-oxidized difference spectra at room and at low temperature. At room temperature, all of these fungi have a c-type cytochrome with an absorption maximum at 551 mμ and a b-type cytochrome at 564 mμ. The Oomycetes have a-type cytochromes at 605 mμ, and the Chytridiomycetes have a-type cytochromes at 606 mμ (Blastocladiales) or at 609 mμ (Monoblepharidales). Additional b-type cytochromes are found at 557 mμ in the Oomycetes and at approximately 560 mμ in the Chytridiomycetes. The data obtained from spectra at low temperature are consistent with these conclusions. Thus, the difference spectra reveal variation between the cytochrome systems of these two classes of aquatic fungi. PMID:5650068

  4. Speciation in fungi.

    PubMed

    Giraud, Tatiana; Refrégier, Guislaine; Le Gac, Mickaël; de Vienne, Damien M; Hood, Michael E

    2008-06-01

    In this review on fungal speciation, we first contrast the issues of species definition and species criteria and show that by distinguishing the two concepts the approaches to studying the speciation can be clarified. We then review recent developments in the understanding of modes of speciation in fungi. Allopatric speciation raises no theoretical problem and numerous fungal examples exist from nature. We explain the theoretical difficulties raised by sympatric speciation, review the most recent models, and provide some natural examples consistent with speciation in sympatry. We describe the nature of prezygotic and postzygotic reproductive isolation in fungi and examine their evolution as functions of temporal and of the geographical distributions. We then review the theory and evidence for roles of cospeciation, host shifts, hybridization, karyotypic rearrangement, and epigenetic mechanisms in fungal speciation. Finally, we review the available data on the genetics of speciation in fungi and address the issue of speciation in asexual species.

  5. Surface properties of beached plastic pellets.

    PubMed

    Fotopoulou, Kalliopi N; Karapanagioti, Hrissi K

    2012-10-01

    The presence of pollutants on plastic debris is an emerging environmental hot topic. Understanding the surface alteration of plastics while in the marine environment increases our understanding of the pollutant-plastic debris interaction. Plastic pellets are widely distributed throughout the world oceans. Eroded and virgin polyethylene (PE) and polypropylene (PP) pellets were studied for their surface properties to better understand the interaction between plastic and compounds in marine environment. Surface properties such as point of zero charge, surface area and pore volume, surface topography, functional groups and acid-base behavior are important factors which affect sorption. Virgin plastic pellets had homogeneous smooth surfaces that do not have any acid-base behavior. Eroded PE demonstrates an altered surface that at seawater pH acquires a negative charge due to ketone groups. The uneven surface and possible functional groups could have been formed from the erosion processes while floating at the sea surface and might explain the interaction of eroded plastics with microbes and metals. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. On the Ablation Models of Fuel Pellets

    SciTech Connect

    Rozhansky, V.A.; Senichenkov, I.Yu.

    2005-12-15

    The neutral gas shielding model and neutral-gas-plasma shielding model are analyzed qualitatively. The main physical processes that govern the formation of the shielding gas cloud and, consequently, the ablation rate are considered. For the neutral gas shielding model, simple formulas relating the ablation rate and cloud parameters to the parameters of the pellet and the background plasma are presented. The estimates of the efficiency of neutral gas shielding and plasma shielding are compared. It is shown that the main portion of the energy flux of the background electrons is released in the plasma cloud. Formulas for the ablation rate and plasma parameters are derived in the neutral-gas-plasma shielding model. The question is discussed as to why the neutral gas shielding model describes well the ablation rate of the pellet material, although it does not take into account the ionization effects and the effects associated with the interaction of ionized particles with the magnetic field. The reason is that the ablation rate depends weakly on the energy flux of hot electrons; as a result, the attenuation of this flux by the electrostatic shielding and plasma shielding has little effect on the ablation rate. This justifies the use of the neutral gas shielding model to estimate the ablation rate (to within a factor of about 2) over a wide range of parameters of the pellet and the background plasma.

  7. Fabrication of high exposure nuclear fuel pellets

    DOEpatents

    Frederickson, James R.

    1987-01-01

    A method is disclosed for making a fuel pellet for a nuclear reactor. A mixture is prepared of PuO.sub.2 and UO.sub.2 powders, where the mixture contains at least about 30% PuO.sub.2, and where at least about 12% of the Pu is the Pu.sup.240 isotope. To this mixture is added about 0.3 to about 5% of a binder having a melting point of at least about 250.degree. F. The mixture is pressed to form a slug and the slug is granulated. Up to about 4.7% of a lubricant having a melting point of at least about 330.degree. F. is added to the granulated slug. Both the binder and the lubricant are selected from a group consisting of polyvinyl carboxylate, polyvinyl alcohol, naturally occurring high molecular weight cellulosic polymers, chemically modified high molecular weight cellulosic polymers, and mixtures thereof. The mixture is pressed to form a pellet and the pellet is sintered.

  8. The plant pathogenic fungus Gaeumannomyces graminis var. tritici improves bacterial growth and triggers early gene regulations in the biocontrol strain Pseudomonas fluorescens Pf29Arp.

    PubMed

    Barret, M; Frey-Klett, P; Boutin, M; Guillerm-Erckelboudt, A-Y; Martin, F; Guillot, L; Sarniguet, A

    2009-01-01

    In soil, some antagonistic rhizobacteria contribute to reduce root diseases caused by phytopathogenic fungi. Direct modes of action of these bacteria have been largely explored; however, commensal interaction also takes place between these microorganisms and little is known about the influence of filamentous fungi on bacteria. An in vitro confrontation bioassay between the pathogenic fungus Gaeumannomyces graminis var. tritici (Ggt) and the biocontrol bacterial strain Pseudomonas fluorescens Pf29Arp was set up to analyse bacterial transcriptional changes induced by the fungal mycelium at three time-points of the interaction before cell contact and up until contact. For this, a Pf29Arp shotgun DNA microarray was constructed. Specifity of Ggt effect was assessed in comparison with one of two other filamentous fungi, Laccaria bicolor and Magnaporthe grisea. During a commensal interaction, Ggt increased the growth rate of Pf29Arp. Before contact, Ggt induced bacterial genes involved in mycelium colonization. At contact, genes encoding protein of stress response and a patatin-like protein were up-regulated. Among all the bacterial genes identified, xseB was specifically up-regulated at contact by Ggt but down-regulated by the other fungi. Data showed that the bacterium sensed the presence of the fungus early, but the main gene alteration occurred during bacterial-fungal cell contact.

  9. Fungi in Bioremediation

    NASA Astrophysics Data System (ADS)

    Gadd, G. M.

    2001-12-01

    Bioremediation research has concentrated on organic pollutants, although the range of substances that can be transformed or detoxified by microorganisms includes both natural and synthetic organic materials and inorganic pollutants. The majority of applications developed to date involve bacteria, with a distinct lack of appreciation of the potential roles and involvement of fungi in bioremediation, despite clear evidence of their metabolic and morphological versatility. This book highlights the potential of filamentous fungi, including mycorrhizas, in bioremediation and discusses the physiology and chemistry of pollutant transformations.

  10. Effects of pellet characteristics on L-lactic acid fermentation by R. oryzae: pellet morphology, diameter, density, and interior structure.

    PubMed

    Fu, Yong-Qian; Yin, Long-Fei; Zhu, Hua-Yue; Jiang, Ru; Li, Shuang; Xu, Qing

    2014-11-01

    The effects of pellet morphology, diameter, density, and interior structure on L-lactic acid fermentation by Rhizopus oryzae were characterized for different inoculum sizes and concentrations of peptone and CaCO3. Inoculum size was the most important factor determining pellet formation and diameter. The diameter decreased with increasing inoculum size, and larger pellets were observed for lower inoculum sizes. Peptone concentration had the greatest effect on pellet density, which increased with increasing peptone concentration. L-lactic acid production depended heavily on pellet density but not on pellet diameter. Low-density pellets formed easily under conditions of low peptone concentration and often had a relatively hollow structure, with a thin condensed layer surrounding the pellet and an extraordinarily loose biomass or hollow center. As expected, this structure greatly decreased production. The production of L-lactic acid increased until the density reached a certain level (50-60 kg/m(3)), in which the compact part was distributed homogeneously in the thick outer layer of the pellet and loose in the central layer. Homogeneously structured, denser pellets had limited mass transfer, causing a lower overall turnover rate. However, the interior structure remained nearly constant throughout all fermentation phases for pellets with the same density. CaCO3 concentration only had a slight influence on pellet diameter and density, probably because it increases spore germination and filamentous hypha extension. This work also provides a new analysis method to quantify the interior structure of pellets, thus giving insight into pellet structure and its relationship with productivity.

  11. Can Plant Microbiome Studies Lead to Effective Biocontrol of Plant Diseases?

    PubMed

    Ellis, Jeffrey G

    2017-03-01

    In this review, the wisdom and efficacy of studies seeking disease attenuating microbes and microbiomes only in healthy plant communities is questioned and an alternative view is posited, namely that success in biocontrol of crop diseases may also come from studies of microbiota, or at least individual species isolates, associated with diseased plants. In support of this view, I summarize the current extensive knowledge of the biology behind what is probably the most successful biocontrol of a plant disease, namely the biocontrol of crown gall of stone fruit using non-pathogenic Rhizobium rhizogenes K84, in which the biocontrol agent itself came from a diseased plant.

  12. Reduced germination of Orobanche cumana seeds in the presence of Arbuscular Mycorrhizal fungi or their exudates.

    PubMed

    Louarn, Johann; Carbonne, Francis; Delavault, Philippe; Bécard, Guillaume; Rochange, Soizic

    2012-01-01

    Broomrapes (Orobanche and Phelipanche spp) are parasitic plants responsible for important crop losses, and efficient procedures to control these pests are scarce. Biological control is one of the possible strategies to tackle these pests. Arbuscular Mycorrhizal (AM) fungi are widespread soil microorganisms that live symbiotically with the roots of most plant species, and they have already been tested on sorghum for their ability to reduce infestation by witchweeds, another kind of parasitic plants. In this work AM fungi were evaluated as potential biocontrol agents against Orobanche cumana, a broomrape species that specifically attacks sunflower. When inoculated simultaneously with O. cumana seeds, AM fungi could offer a moderate level of protection against the broomrape. Interestingly, this protection did not only rely on a reduced production of parasitic seed germination stimulants, as was proposed in previous studies. Rather, mycorrhizal root exudates had a negative impact on the germination of O. cumana induced by germination stimulants. A similar effect could be obtained with AM spore exudates, establishing the fungal origin of at least part of the active compounds. Together, our results demonstrate that AM fungi themselves can lead to a reduced rate of parasitic seed germination, in addition to possible effects mediated by the mycorrhizal plant. Combined with the other benefits of AM symbiosis, these effects make AM fungi an attractive option for biological control of O. cumana.

  13. Impact of plant species and site on rhizosphere-associated fungi antagonistic to Verticillium dahliae kleb.

    PubMed

    Berg, Gabriele; Zachow, Christin; Lottmann, Jana; Götz, Monika; Costa, Rodrigo; Smalla, Kornelia

    2005-08-01

    Fungi with antagonistic activity toward plant pathogens play an essential role in plant growth and health. To analyze the effects of the plant species and the site on the abundance and composition of fungi with antagonistic activity toward Verticillium dahliae, fungi were isolated from oilseed rape and strawberry rhizosphere and bulk soil from three different locations in Germany over two growing seasons. A total of 4,320 microfungi screened for in vitro antagonism toward Verticillium resulted in 911 active isolates. This high proportion of fungi antagonistic toward the pathogen V. dahliae was found for bulk and rhizosphere soil at all sites. A plant- and site-dependent specificity of the composition of antagonistic morphotypes and their genotypic diversity was found. The strawberry rhizosphere was characterized by preferential occurrence of Penicillium and Paecilomyces isolates and low numbers of morphotypes (n = 31) and species (n = 13), while Monographella isolates were most frequently obtained from the rhizosphere of oilseed rape, for which higher numbers of morphotypes (n = 41) and species (n = 17) were found. Trichoderma strains displayed high diversity in all soils, but a high degree of plant specificity was shown by BOX-PCR fingerprints. The diversity of rhizosphere-associated antagonists was lower than that of antagonists in bulk soil, suggesting that some fungi were specifically enriched in each rhizosphere. A broad spectrum of new Verticillium antagonists was identified, and the implications of the data for biocontrol applications are discussed.

  14. Perspectives on the potential of entomopathogenic fungi in biological control of ticks.

    PubMed

    Fernandes, Éverton K K; Bittencourt, Vânia R E P; Roberts, Donald W

    2012-03-01

    Ticks are serious health threats for humans, and both domestic and wild animals. Ticks are controlled mostly by application of chemical products; but these acaricides have several negative side effects, including toxicity to animals, environmental contamination, and induction of chemical resistance in some tick populations. Entomopathogenic fungi infect arthropods in nature and can occur at enzootic or epizootic levels in their host populations. Laboratory studies clearly demonstrate that these fungi can cause high mortality in all developmental stages of several tick species, and also reduce oviposition of infected engorged females. Tick mortality following application of fungi in the field, however, often is less than that suggested by laboratory tests. This is due to many negative biotic and climatic factors. To increase efficacy of fungal agents for biological control of ticks under natural conditions, several points need consideration: (1) select effective isolates (viz., high virulence; and tolerance to high temperature, ultraviolet radiation and desiccation); (2) understand the main factors that affect virulence of fungal isolates to their target arthropods including the role of toxic metabolites of the fungal isolates; and (3) define with more precision the immune response of ticks to infection by entomopathogenic fungi. The current study reviews recent literature on biological control of ticks, and comments on the relevance of these results to advancing the development of fungal biocontrol agents, including improving formulation of fungal spores for use in tick control, and using entomopathogenic fungi in integrated pest (tick) management programs. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Gene cloning, molecular modeling, and phylogenetics of serine protease P32 and serine carboxypeptidase SCP1 from nematophagous fungi Pochonia rubescens and Pochonia chlamydosporia.

    PubMed

    Larriba, Eduardo; Martín-Nieto, José; Lopez-Llorca, Luis Vicente

    2012-07-01

    The fungi Pochonia chlamydosporia and Pochonia rubescens are parasites of nematode eggs and thus are biocontrol agents of nematodes. Proteolytic enzymes such as the S8 proteases VCP1 and P32, secreted during the pathogenesis of nematode eggs, are major virulence factors in these fungi. Recently, expression of these enzymes and of SCP1, a new putative S10 carboxypeptidase, was detected during endophytic colonization of barley roots by these fungi. In our study, we cloned the genomic and mRNA sequences encoding P32 from P. rubescens and SCP1 from P. chlamydosporia. P32 showed a high homology with the serine proteases Pr1A from the entomopathogenic fungus Metarhizium anisopliae and VCP1 from P. chlamydosporia (86% and 76% identity, respectively). However, the catalytic pocket of P32 showed differences in the amino acids of the substrate-recognition sites compared with the catalytic pockets of Pr1A and VCP1 proteases. Phylogenetic analysis of P32 suggests a common ancestor with protease Pr1A. SCP1 displays the characteristic features of a member of the S10 family of serine proteases. Phylogenetic comparisons show that SCP1 and other carboxypeptidases from filamentous fungi have an origin different from that of yeast vacuolar serine carboxypeptidases. Understanding protease genes from nematophagous fungi is crucial for enhancing the biocontrol potential of these organisms.

  16. Improvement of Biocontrol of Damping-off and Root Rot/Wilt of Faba Bean by Salicylic Acid and Hydrogen Peroxide.

    PubMed

    Abdel-Monaim, Montaser Fawzy

    2013-03-01

    Rhizoctonia solani, Fusarium solani, F. oxysporum, and Macrophomina phaseolina were found to be associated with root rott and wilt symptoms of faba bean plants collected from different fieldes in New Valley governorate, Egypt. All the obtained isolates were able to attack faba bean plants (cv. Giza 40) causing damping-off and root rot/wilt diseases. R. solani isolates 2 and 5, F. solani isolate 8, F. oxysporum isolate 12 and M. phaseolina isolate 14 were the more virulent ones in the pathogenicity tests. Biocontrol agents (Trichoderma viride and Bacillus megaterium) and chemical inducers (salicylic acid [SA] and hydrogen peroxide) individually or in combination were examined for biological control of damping-off and root rot/wilt and growth promoting of faba bean plants in vitro and in vivo. Both antagonistic biocontrol agents and chemical inducers either individually or in combination inhibited growth of the tested pathogenic fungi. Biocontrol agents combined with chemical inducers recorded the highest inhibited growth especially in case SA + T. viride and SA + B. megaterium. Under green house and field conditions, all treatments significantly reduced damping-off and root rot/wilt severity and increased of survival plants. Also, these treatments increased fresh and weights of the survival plants in pots compared with control. The combination between biocontrol agents and chemical inducers were more effective than used of them individually and SA + T. viride was the best treatment in this respect. Also, under field conditions, all these treatments significantly increased growth parameters (plant height and number of branches per plant) and yield components (number of pods per plant and number of seeds per plant, weight of 100 seeds and total yield per feddan) and protein content in both seasons (2010~2011 and 2011~2012). Faba bean seeds soaked in SA + T. viride and SA + B. megaterium were recorded the highest growth parameters and yield components. Generally, the

  17. Improvement of Biocontrol of Damping-off and Root Rot/Wilt of Faba Bean by Salicylic Acid and Hydrogen Peroxide

    PubMed Central

    2013-01-01

    Rhizoctonia solani, Fusarium solani, F. oxysporum, and Macrophomina phaseolina were found to be associated with root rott and wilt symptoms of faba bean plants collected from different fieldes in New Valley governorate, Egypt. All the obtained isolates were able to attack faba bean plants (cv. Giza 40) causing damping-off and root rot/wilt diseases. R. solani isolates 2 and 5, F. solani isolate 8, F. oxysporum isolate 12 and M. phaseolina isolate 14 were the more virulent ones in the pathogenicity tests. Biocontrol agents (Trichoderma viride and Bacillus megaterium) and chemical inducers (salicylic acid [SA] and hydrogen peroxide) individually or in combination were examined for biological control of damping-off and root rot/wilt and growth promoting of faba bean plants in vitro and in vivo. Both antagonistic biocontrol agents and chemical inducers either individually or in combination inhibited growth of the tested pathogenic fungi. Biocontrol agents combined with chemical inducers recorded the highest inhibited growth especially in case SA + T. viride and SA + B. megaterium. Under green house and field conditions, all treatments significantly reduced damping-off and root rot/wilt severity and increased of survival plants. Also, these treatments increased fresh and weights of the survival plants in pots compared with control. The combination between biocontrol agents and chemical inducers were more effective than used of them individually and SA + T. viride was the best treatment in this respect. Also, under field conditions, all these treatments significantly increased growth parameters (plant height and number of branches per plant) and yield components (number of pods per plant and number of seeds per plant, weight of 100 seeds and total yield per feddan) and protein content in both seasons (2010~2011 and 2011~2012). Faba bean seeds soaked in SA + T. viride and SA + B. megaterium were recorded the highest growth parameters and yield components. Generally, the

  18. Permeability of wood pellets in the presence of fines.

    PubMed

    Yazdanpanah, F; Sokhansanj, S; Lau, A K; Lim, C J; Bi, X; Melin, S; Afzal, M

    2010-07-01

    Broken pellets and fines are produced when pellets are handled. The resistance to air flow was measured for clean pellets and for pellets mixed with 1-20% broken pellets (fines). A pellet diameter was 6mm. The lengths ranged from 6 to 12 mm. Clean pellets were defined as particles that remained on a 4mm screen. A typical sieve analysis showed 30% of the mass of particles that passed through the 4mm screen was smaller than 1mm. The airflow rates used in the experiment ranged from 0.004 to 0.357 ms(-1). The corresponding pressure drop ranged from 1.9 to 271 Pam(-1) for clean pellets, from 4.8 to 1100 Pam(-1) for 10% fines content, and from 7.9 to 1800 Pam(-1) for 20% fines content. Coefficients of Hukill and Ives' equation were estimated for clean pellets and a multiplier was defined to calculate pressure drop for pellets mixed with fines.

  19. Influences on particle shape in underwater pelletizing processes

    SciTech Connect

    Kast, O. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de; Musialek, M. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de; Geiger, K. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de; Bonten, C. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de

    2014-05-15

    Underwater pelletizing has gained high importance within the last years among the different pelletizing technologies, due to its advantages in terms of throughput, automation, pellet quality and applicability to a large variety of thermoplastics. The resulting shape and quality of pellets, however, differ widely, depending on material characteristics and effects not fully understood yet. In an experimental set-up, pellets of different volumes and shapes were produced and the medium pellet mass, the pellet surface and the bulk density were analyzed in order to identify the influence of material properties and process parameters. Additionally, the shaping kinetics at the die opening were watched with a specially developed camera system. It was found that rheological material properties correlate with process parameters and resulting particle form in a complex way. Higher cutting speeds were shown to have a deforming influence on the pellets, leading to less spherical s and lower bulk densities. More viscous materials, however, showed a better resistance against this. Generally, the viscous properties of polypropylene proofed to be dominant over the elastic ones in regard to their influence on pellet shape. It was also shown that the shapes filmed at the die opening and the actual form of the pellets after a cooling track do not always correlate, indicating a significant influence of thermodynamic properties during the cooling.

  20. Cryogenic pellet production developments for long-pulse plasma operation

    SciTech Connect

    Meitner, S. J.; Baylor, L. R.; Combs, S. K.; Fehling, D. T.; McGill, J. M.; Duckworth, R. C.; McGinnis, W. D.; Rasmussen, D. A.

    2014-01-29

    Long pulse plasma operation on large magnetic fusion devices require multiple forms of cryogenically formed pellets for plasma fueling, on-demand edge localized mode (ELM) triggering, radiative cooling of the divertor, and impurity transport studies. The solid deuterium fueling and ELM triggering pellets can be formed by extrusions created by helium cooled, twin-screw extruder based injection system that freezes deuterium in the screw section. A solenoid actuated cutter mechanism is activated to cut the pellets from the extrusion, inserting them into the barrel, and then fired by the pneumatic valve pulse of high pressure gas. Fuel pellets are injected at a rate up to 10 Hz, and ELM triggering pellets are injected at rates up to 20 Hz. The radiative cooling and impurity transport study pellets are produced by introducing impurity gas into a helium cooled section of a pipe gun where it deposits in-situ. A pneumatic valve is opened and propellant gas is released downstream where it encounters a passive punch which initially accelerates the pellet before the gas flow around the finishes the pellet acceleration. This paper discusses the various cryogenic pellet production techniques based on the twin-screw extruder, pipe gun, and pellet punch designs.

  1. A fuel pellet injector for the Microwave Tokamak Experiment (MTX)

    SciTech Connect

    Hibbs, S.M.; Allen, S.L.; Petersen, D.E.; Sewall, N.R.

    1990-09-01

    Unlike other fueling systems for magnetically confined fusion plasmas, a pellet injector can deliver many fuel gas particles to the core of the plasma, enhancing plasma confinement. We installed a new pellet injector on the MTX (formerly Alcator-O) to provide a plasma with a high core density for experiments both with and without ultrahigh-power microwave heating. Its four-barrel pellet generator is the first to be designed and built at LLNL. Based on pipe-gun'' technology originated at Oak Ridge National Laboratory (ORNL), it incorporates our structural and thermal engineering innovations and a unique control system. The pellet transport, differential vacuum-pumping stages, and fast-opening propellant valves are reused parts of the Impurity Study EXperiment (ISX) pellet injector built by ORNL. We tailored designs of all other systems and components to the MTX. Our injector launches pellets of frozen hydrogen or deuterium into the MTX, either singly or in timed bursts of up to four pellets at velocities of up to 1000 m/s. Pellet diameters range from 1.02 to 2.08 mm. A diagnostic stage measures pellet velocities and allows us to photograph the pellets in flight. We are striving to improve the injector's performance, but its operations is already very consistent and reliable.

  2. Putative use of a Bacillus subtilis L194 strain for biocontrol of Phoma medicaginis in Medicago truncatula seedlings.

    PubMed

    Ben Slimene, Imen; Tabbene, Olfa; Djebali, Naceur; Cosette, Pascal; Schmitter, Jean Marie; Jouenne, Thierry; Urdaci, Maria-Camino; Limam, Ferid

    2012-06-01

    An antagonist L194 strain against Phoma medicaginis pathogenic fungi was isolated from Tunisian soil (vicinity of Tunis) and identified as Bacillus subtilis based on biochemical characteristics and partial 16S rDNA sequence. When cells were grown in a minimal medium for 24 h, spore culture supernatant exhibited 2-fold higher antifungal activity than vegetative cells. MALDI-TOF mass spectrometry analysis showed that L194 spores produced mainly iturins, surfactins and fengycins with long-chain fatty acids, and other not yet identified compounds. Both vegetative cells and spores of L194 efficiently reduced germination of P. medicaginis conidia. As revealed by atomic force microscopy, L194 spores modified conidia morphology from a regular to a deflated shape. Data suggest that lipopeptides interacted with the cytoplasmic membrane, causing pore formation. In vivo, L194 spores were highly protective against P. medicaginis by reducing disease symptoms and alleviating growth disturbance of Medicago truncatula seedlings. As a whole, the lipopeptide-producing L194 strain may be successfully used in biocontrol of plant diseases induced by phytopathogenic fungi such as P. medicaginis.

  3. Physiological characteristics of the biocontrol yeast Pichia anomala J121.

    PubMed

    Fredlund, Elisabeth; Druvefors, Ulrika; Boysen, Marianne E; Lingsten, Karl-Johan; Schnürer, Johan

    2002-08-01

    The yeast Pichia anomala J121 prevents mold spoilage and enhances preservation of moist grain in malfunctioning storage systems. Development of P. anomala J121 as a biocontrol agent requires in-depth knowledge about its physiology. P. anomala J121 grew under strictly anaerobic conditions, at temperatures between 3 degrees C and 37 degrees C, at pH values between 2.0 and 12.4, and at a water activity of 0.92 (NaCl) and 0.85 (glycerol). It could assimilate a wide range of C- and N-sources and produce killer toxin. A selective medium containing starch, nitrate, acetic acid, and chloramphenicol was developed for P. anomala. P. anomala was equally sensitive as Candida albicans to common antifungal compounds. Growth ability at a range of environmental conditions contributes to the competitive ability of the biocontrol yeast P. anomala J121.

  4. Viral biocontrol: grand experiments in disease emergence and evolution.

    PubMed

    Di Giallonardo, Francesca; Holmes, Edward C

    2015-02-01

    Although viral emergence is commonly associated with cross-species transmission, the processes and determinants of viral evolution in a novel host environment are poorly understood. We address key questions in virus emergence and evolution using data generated from two unique natural experiments: the deliberate release of myxoma virus (MYXV) and rabbit hemorrhagic disease virus (RHDV) as biological control (biocontrol) agents against the European rabbit in Australia, and which have been of enormous benefit to Australia's ecosystem and agricultural industries. Notably, although virulence evolution in MYXV and RHDV followed different trajectories, a strongly parallel evolutionary process was observed in Australia and Europe. These biocontrol agents were also characterized by a lack of transmission to nontarget host species, suggesting that there are major barriers to successful emergence. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Viral biocontrol: grand experiments in disease emergence and evolution

    PubMed Central

    Di Giallonardo, Francesca; Holmes, Edward C.

    2014-01-01

    Although viral emergence is commonly associated with cross-species transmission, the processes and determinants of viral evolution in a novel host environment are poorly understood. We address key questions in virus emergence and evolution using data generated from two unique natural experiments: the deliberate release of myxoma virus (MYXV) and rabbit hemorrhagic disease virus (RHDV) as biological control (biocontrol) agents against the European rabbit in Australia, and which have been of enormous benefit to Australia’s ecosystem and agricultural industries. Notably, although virulence evolution in MYXV and RHDV followed different trajectories, a strongly parallel evolutionary process was observed in Australia and Europe. These biocontrol agents were also characterised by a lack of transmission to non-target host species, suggesting that there are major barriers to successful emergence. PMID:25455418

  6. Comparative efficacy and pathogenicity of keratinophilic soil fungi against Culex quinquefasciatus larvae.

    PubMed

    Mohanty, Suman Sundar; Prakash, Soam

    2010-09-01

    Out of seven fungal species belonging to four genera isolated from pond and wallow soils using feathers of Pavo cristatus as bait, four species viz., Aspergillus flavus, Aspergillus niger, Chrysosporium pseudomerdarium and Trichophyton ajelloi were most frequent. Chrysosporium and Trichophyton spp. were more pathogenic on Culex quinquefasciatus larvae than Aspergillus and Penicillium. The bioefficacy tests conducted as per the protocol of World Health Organization and the LC(50) values calculated by the Probit analysis showed that 3(rd)-instar C. quinquefasciatus were more susceptible to the conidia of above fungi. Highest mortality was observed in the larvae of C. quinquefasciatus when exposed to T. ajelloi. The density of fungal conidia was greatest on the ventral brush, palmate hair and anal region of the mosquito larvae after exposing for 72 hours. The potentiality of these fungi for use in the control of C. quinquefasciatus is discussed which can be exploited as a suitable biocontrol agent in the tropics.

  7. Novel-shaped catalyst pellets for packed-bed reactors

    SciTech Connect

    Punuru, A.R.

    1987-01-01

    The effect of the shape of a catalyst pellet, on the performance of a packed bed reactor, is determined by evaluating the effectiveness factor and dimensionless overall rates of the catalyst pellet. Depending upon the values of Thiele modulus and Prater number the use of Novel-shaped catalyst pellets, such as Lessing ring type pellets or partition ring type pellets or spoked wheel type pellets, which improve the overall rate of the pellet, were suggested. The novel-shaped pellets were sectioned into a hollow cylinder and slabs. The dimensionless rates and effectiveness factors were determined for hollow cylinders and slabs separately and the total dimensionless overall rate for the pellet is obtained by adding, the individual rates for slabs and hollow cylinder. The catalyst shape effects were studied on the steam-methane reformer. It was found that using traditional catalyst, a hollow cylindrical pellet with R/sub i//R/sub p/ ratio of 0.39, the dimensionless overall rate decreased from 0.75 at the top, to 0.27 at the bottom of the reformer. Upon using Lessing rings at the top, partition rings at the center, and spoked wheel pellets at the bottom of the reformer, the reaction rate can be improved to 0.9 at the top and to 0.73 at the bottom of the reformer. Though benzene-hydrogenation is exothermic reaction, use of solid cylindrical pellet was suggested, because of the low Thiele modulus. Two-dimensional pseudo homogeneous and heterogeneous reactor models were solved for a first order nonisothermal reaction, considering isothermal pellets. The inclusion of nonisothermal effectiveness factor that consider shape effects was left for future work.

  8. Selection rhizosphere-competent microbes for development of microbial products as biocontrol agents

    NASA Astrophysics Data System (ADS)

    Mashinistova, A. V.; Elchin, A. A.; Gorbunova, N. V.; Muratov, V. S.; Kydralieva, K. A.; Khudaibergenova, B. M.; Shabaev, V. P.; Jorobekova, Sh. J.

    2009-04-01

    Rhizosphere-borne microorganisms reintroduced to the soil-root interface can establish without inducing permanent disturbance in the microbial balance and effectively colonise the rhizosphere due to carbon sources of plant root exudates. A challenge for future development of microbial products for use in agriculture will be selection of rhizosphere-competent microbes that both protect the plant from pathogens and improve crop establishment and persistence. In this study screening, collection, identification and expression of stable and technological microbial strains living in soils and in the rhizosphere of abundant weed - couch-grass Elytrigia repens L. Nevski were conducted. A total of 98 bacteria isolated from the rhizosphere were assessed for biocontrol activity in vitro against phytopathogenic fungi including Fusarium culmorum, Fusarium heterosporum, Fusarium oxysporum, Drechslera teres, Bipolaris sorokiniana, Piricularia oryzae, Botrytis cinerea, Colletothrichum atramentarium and Cladosporium sp., Stagonospora nodorum. Biocontrol activity were performed by the following methods: radial and parallel streaks, "host - pathogen" on the cuts of wheat leaves. A culture collection comprising 64 potential biocontrol agents (BCA) against wheat and barley root diseases has been established. Of these, the most effective were 8 isolates inhibitory to at least 4 out of 5 phytopathogenic fungi tested. The remaining isolates inhibited at least 1 of 5 fungi tested. Growth stimulating activity of proposed rhizobacteria-based preparations was estimated using seedling and vegetative pot techniques. Seeds-inoculation and the tests in laboratory and field conditions were conducted for different agricultural crops - wheat and barley. Intact cells, liquid culture filtrates and crude extracts of the four beneficial bacterial strains isolated from the rhizosphere of weed were studied to stimulate plant growth. As a result, four bacterial strains selected from rhizosphere of weed

  9. Effect of temperature and water activity on spore germination and mycelial growth of three fungal biocontrol agents against water hyacinth (Eichhornia crassipes).

    PubMed

    Dagno, K; Lahlali, R; Diourté, M; Jijakli, M H

    2011-02-01

    To determine the effect of water activity (a(w) =0·880-0·960) and temperature (15-35°C) on the percentage of viable conidia and mycelial growth of three biocontrol agents effective against water hyacinth in Mali: Alternaria sp. isolate Mlb684, Fusarium sacchari isolate Mln799 and Cadophora malorum isolate Mln715. The fungi were grown in vitro on plates containing potato dextrose agar medium at different a(w) values (glycerol being added to adjust the a(w)). The percentage of viable conidia and radial growth rate decreased with decreasing water activity. Statistical analysis showed a significant effect of a(w), temperature and the a(w) × temperature interaction on mycelial growth (P<0·0001). Water activity emerged as the factor exerting the greatest influence. Differences were observed between the fungi tested, the C. malorum appearing more tolerant to low a(w) and the F. sacchari more tolerant to high temperature (35°C). Growth models predicting the combined effect of a(w) and temperature were developed and response surfaces generated, showing fairly good agreement with the experimental values. Our results confirm the previous finding that a(w) has a greater influence than temperature on fungal growth. Under most conditions, variation of environmental factors has a detrimental influence on the percentage of viable conidia and mycelial growth rate of fungal isolates. The developed models may contribute to predicting the best environmental conditions for use of these fungi as effective biocontrol agents against water hyacinth. © 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.

  10. A critical review on fungi mediated plant responses with special emphasis to Piriformospora indica on improved production and protection of crops.

    PubMed

    Ansari, Mohammad Wahid; Trivedi, Dipesh Kumar; Sahoo, Ranjan Kumar; Gill, Sarvajeet Singh; Tuteja, Narendra

    2013-09-01

    The beneficial fungi are potentially useful in agriculture sector to avail several services to crop plants such as water status, nutrient enrichment, stress tolerance, protection, weed control and bio-control. Natural agro-ecosystem relies on fungi because of it takes part in soil organic matter decomposition, nutrient acquisition, organic matter recycling, nutrient recycling, antagonism against plant pests, and crop management. The crucial role of fungi in normalizing the toxic effects of phenols, HCN and ROS by β-CAS, ACC demainase and antioxidant enzymes in plants is well documented. Fungi also play a part in various physiological processes such as water uptake, stomatal movement, mineral uptake, photosynthesis and biosynthesis of lignan, auxins and ethylene to improve growth and enhance plant fitness to cope heat, cold, salinity, drought and heavy metal stress. Here, we highlighted the ethylene- and cyclophilin A (CypA)-mediated response of Piriformospora indica for sustainable crop production under adverse environmental conditions.

  11. Fungi that Infect Humans.

    PubMed

    Köhler, Julia R; Hube, Bernhard; Puccia, Rosana; Casadevall, Arturo; Perfect, John R

    2017-06-01

    Fungi must meet four criteria to infect humans: growth at human body temperatures, circumvention or penetration of surface barriers, lysis and absorption of tissue, and resistance to immune defenses, including elevated body temperatures. Morphogenesis between small round, detachable cells and long, connected cells is the mechanism by which fungi solve problems of locomotion around or through host barriers. Secretion of lytic enzymes, and uptake systems for the released nutrients, are necessary if a fungus is to nutritionally utilize human tissue. Last, the potent human immune system evolved in the interaction with potential fungal pathogens, so few fungi meet all four conditions for a healthy human host. Paradoxically, the advances of modern medicine have made millions of people newly susceptible to fungal infections by disrupting immune defenses. This article explores how different members of four fungal phyla use different strategies to fulfill the four criteria to infect humans: the Entomophthorales, the Mucorales, the Ascomycota, and the Basidiomycota. Unique traits confer human pathogenic potential on various important members of these phyla: pathogenic Onygenales comprising thermal dimorphs such as Histoplasma and Coccidioides; the Cryptococcus spp. that infect immunocompromised as well as healthy humans; and important pathogens of immunocompromised patients-Candida, Pneumocystis, and Aspergillus spp. Also discussed are agents of neglected tropical diseases important in global health such as mycetoma and paracoccidiomycosis and common pathogens rarely implicated in serious illness such as dermatophytes. Commensalism is considered, as well as parasitism, in shaping genomes and physiological systems of hosts and fungi during evolution.

  12. Fun with Fungi.

    ERIC Educational Resources Information Center

    McLure, John W.

    1993-01-01

    Describes hands-on activities with fungi that may provoke the curiosity of early adolescents and increase their enjoyment and understanding of a vast, important portion of botany. Some of the activities may be conducted during the winter months when most fieldwork ceases. (PR)

  13. Rust fungi on Panicum

    USDA-ARS?s Scientific Manuscript database

    Rusts are economically important diseases of switchgrass and other Panicum grasses. Phylogenetic analyses based on sequences of the rDNA internal transcribed spacer ITS2 region, the large subunit, and the intergenic spacer region (IGS) showed that species of rust fungi infecting switchgrass are clos...

  14. Adaptive Immunity to Fungi

    PubMed Central

    Verma, Akash; Wüthrich, Marcel; Deepe, George; Klein, Bruce

    2015-01-01

    Life-threatening fungal infections have risen sharply in recent years, owing to the advances and intensity of medical care that may blunt immunity in patients. This emerging crisis has created the growing need to clarify immune defense mechanisms against fungi with the ultimate goal of therapeutic intervention. We describe recent insights in understanding the mammalian immune defenses that are deployed against pathogenic fungi. We focus on adaptive immunity to the major medically important fungi and emphasize three elements that coordinate the response: (1) dendritic cells and subsets that are mobilized against fungi in various anatomical compartments; (2) fungal molecular patterns and their corresponding receptors that signal responses and shape the differentiation of T-cell subsets and B cells; and, ultimately (3) the effector and regulatory mechanisms that eliminate these invaders while constraining collateral damage to vital tissue. These insights create a foundation for the development of new, immune-based strategies for prevention or enhanced clearance of systemic fungal diseases. PMID:25377140

  15. Fun with Fungi.

    ERIC Educational Resources Information Center

    McLure, John W.

    1993-01-01

    Describes hands-on activities with fungi that may provoke the curiosity of early adolescents and increase their enjoyment and understanding of a vast, important portion of botany. Some of the activities may be conducted during the winter months when most fieldwork ceases. (PR)

  16. Responses of Yeast Biocontrol Agents to Environmental Stress

    PubMed Central

    Sui, Yuan; Wisniewski, Michael; Droby, Samir

    2015-01-01

    Biological control of postharvest diseases, utilizing wild species and strains of antagonistic yeast species, is a research topic that has received considerable attention in the literature over the past 30 years. In principle, it represents a promising alternative to chemical fungicides for the management of postharvest decay of fruits, vegetables, and grains. A yeast-based biocontrol system is composed of a tritrophic interaction between a host (commodity), a pathogen, and a yeast species, all of which are affected by environmental factors such as temperature, pH, and UV light as well as osmotic and oxidative stresses. Additionally, during the production process, biocontrol agents encounter various severe abiotic stresses that also impact their viability. Therefore, understanding the ecological fitness of the potential yeast biocontrol agents and developing strategies to enhance their stress tolerance are essential to their efficacy and commercial application. The current review provides an overview of the responses of antagonistic yeast species to various environmental stresses, the methods that can be used to improve stress tolerance and efficacy, and the related mechanisms associated with improved stress tolerance. PMID:25710368

  17. [Fungi and atopic dermatitis].

    PubMed

    Hiruma, M; Maeng, D J; Kobayashi, M; Suto, H; Ogawa, H

    1999-01-01

    Attention has recently been centered on fungi as aggravating factors of atopic dermatitis (AD) due to the frequent detection of IgE antibodies to fungi in patients with severe AD and to positive response of some cases of AD to antifungal therapy. Malassezia sp.: In AD patients with prominent symptoms in the head and neck, areas prone to colonization by Malassezia, the titers of specific anti-Malassezia IgE antibodies are high, which positively correlate with the total IgE value and the severity of AD. The patch test against Malassezia antigens is positive. The rate of isolation of Malassezia from the skin of AD patients is higher than that from the skin of healthy control subjects. Candida sp.: In patients with severe AD, the rate of positive skin prick tests for Candida is high, and a correlation exists between positive skin prick test results and the presence of Candida albicans in nasopharynx. However, the reactivity to Candida antigens in the patch tests is reduced, and a negative correlation is seen. There is no difference between the isolation rate of C. albicans from patients with adult-type AD and normal controls. However, AD patients give a significantly greater number of separate colonies. The range of efficacy rate of antifungal therapy of AD is reported to be 50-65 %. The efficacy rate of our own trial falls within this range. Following treatment, the rate of isolation of fungi decrease significantly, and the titers of specific antifungal IgE antibodies are not statistically significant. The clearance of fungi from the tissue following antifungal therapy probably results in the suppression of direct or indirect inflammatory reaction caused by the fungi. We therefore consider antifungal therapy as one of the second-line therapies to be administered in AD cases resistant to conventional basic therapy.

  18. A curious pellet from a great horned owl (Bubo virginianus)

    USGS Publications Warehouse

    Woodman, N.; Dove, C.J.; Peurach, S.C.

    2005-01-01

    One of the traditional methods of determining the dietary preferences of owls relies upon the identification of bony remains of prey contained in regurgitated pellets. Discovery of a pellet containing a large, complete primary feather from an adult, male Ring-necked Pheasant (Phasianus colchicus) prompted us to examine in detail a small sample of pellets from a Great Horned Owl (Bubo virginianus). Our analyses of feather and hair remains in these pellets documented the presence of three species of birds and two species of mammals, whereas bones in the pellets represented only mammals. This finding indicates an important bias that challenges the reliability of owl pellet studies making use of only osteological remains.

  19. Mechanical durability and combustion characteristics of pellets from biomass blends.

    PubMed

    Gil, M V; Oulego, P; Casal, M D; Pevida, C; Pis, J J; Rubiera, F

    2010-11-01

    Biofuel pellets were prepared from biomass (pine, chestnut and eucalyptus sawdust, cellulose residue, coffee husks and grape waste) and from blends of biomass with two coals (bituminous and semianthracite). Their mechanical properties and combustion behaviour were studied by means of an abrasion index and thermogravimetric analysis (TGA), respectively, in order to select the best raw materials available in the area of study for pellet production. Chestnut and pine sawdust pellets exhibited the highest durability, whereas grape waste and coffee husks pellets were the least durable. Blends of pine sawdust with 10-30% chestnut sawdust were the best for pellet production. Blends of cellulose residue and coals (<20%) with chestnut and pine sawdusts did not decrease pellet durability. The biomass/biomass blends presented combustion profiles similar to those of the individual raw materials. The addition of coal to the biomass in low amounts did not affect the thermal characteristics of the blends.

  20. Pellet injectors for the tokamak fusion test reactor

    SciTech Connect

    Combs, S.K.

    1986-01-01

    The repeating pneumatic injector is a device from the ORNL development program. A new eight-shot deuterium pellet injector has been designed and constructed specifically for the TFTR application and is scheduled to replace the repeating injector this year. The new device combines a cryogenic extruder and a cold wheel rotary mechanism to form and chamber eight pellets in a batch operation; the eight pellets can then be delivered in any time sequence. Another unique feature of the device is the variable pellet size with three pellets each of 3.0 and 3.5 mm diam and two each of 4.0 mm diam. The experience and technology that have been developed on previous injectors at ORNL have been utilized in the design of this latest pellet injection system.

  1. Manufacture of Regularly Shaped Sol-Gel Pellets

    NASA Technical Reports Server (NTRS)

    Leventis, Nicholas; Johnston, James C.; Kinder, James D.

    2006-01-01

    An extrusion batch process for manufacturing regularly shaped sol-gel pellets has been devised as an improved alternative to a spray process that yields irregularly shaped pellets. The aspect ratio of regularly shaped pellets can be controlled more easily, while regularly shaped pellets pack more efficiently. In the extrusion process, a wet gel is pushed out of a mold and chopped repetitively into short, cylindrical pieces as it emerges from the mold. The pieces are collected and can be either (1) dried at ambient pressure to xerogel, (2) solvent exchanged and dried under ambient pressure to ambigels, or (3) supercritically dried to aerogel. Advantageously, the extruded pellets can be dropped directly in a cross-linking bath, where they develop a conformal polymer coating around the skeletal framework of the wet gel via reaction with the cross linker. These pellets can be dried to mechanically robust X-Aerogel.

  2. Modeling of MOX Fuel Pellet-Clad Interaction Using ABAQUS

    SciTech Connect

    Ambrosek, Richard G.; Pedersen, Robert C.; Maple, Amanda

    2002-07-01

    Post-irradiation examination (PIE) has indicated an increase in the outer diameter of fuel pins being irradiated in the Advanced Test Reactor (ATR) for the MOX irradiation program. The diameter increase is the largest in the region between fuel pellets. The fuel pellet was modeled using PATRAN and the model was evaluated using ABAQUS, version 6.2. The results from the analysis indicate the non-uniform clad diameter is caused by interaction between the fuel pellet and the clad. The results also demonstrate that the interaction is not uniform over the pellet axial length, with the largest interaction occurring in the region of the pellet-pellet interface. Results were obtained for an axisymmetric model and for a 1/8 pie shaped segment, using the coupled temperature-displacement solution technique. (authors)

  3. Microstructure of bentonite in iron ore green pellets.

    PubMed

    Bhuiyan, Iftekhar U; Mouzon, Johanne; Schröppel, Birgit; Kaech, Andres; Dobryden, Illia; Forsmo, Seija P E; Hedlund, Jonas

    2014-02-01

    Sodium-activated calcium bentonite is used as a binder in iron ore pellets and is known to increase strength of both wet and dry iron ore green pellets. In this article, the microstructure of bentonite in magnetite pellets is revealed for the first time using scanning electron microscopy. The microstructure of bentonite in wet and dry iron ore pellets, as well as in distilled water, was imaged by various imaging techniques (e.g., imaging at low voltage with monochromatic and decelerated beam or low loss backscattered electrons) and cryogenic methods (i.e., high pressure freezing and plunge freezing in liquid ethane). In wet iron ore green pellets, clay tactoids (stacks of parallel primary clay platelets) were very well dispersed and formed a voluminous network occupying the space available between mineral particles. When the pellet was dried, bentonite was drawn to the contact points between the particles and formed solid bridges, which impart strength to the solid compact.

  4. Durable zinc ferrite sorbent pellets for hot coal gas desulfurization

    DOEpatents

    Jha, Mahesh C.; Blandon, Antonio E.; Hepworth, Malcolm T.

    1988-01-01

    Durable, porous sulfur sorbents useful in removing hydrogen sulfide from hot coal gas are prepared by water pelletizing a mixture of fine zinc oxide and fine iron oxide with inorganic and organic binders and small amounts of activators such as sodium carbonate and molybdenite; the pellets are dried and then indurated at a high temperature, e.g., 1800.degree. C., for a time sufficient to produce crush-resistant pellets.

  5. Pellet acceleration using an ablation-controlled electrothermal launcher

    SciTech Connect

    Kincaid, R.W.; Bourham, M.A.; Gilligan, J.G.

    1995-12-31

    The NCSU ablation-controlled electrothermal launcher SIRENS has been used to accelerate plastic (Lexan polycarbonate) pellets to investigate the possibility of using electrothermal launchers as frozen pellet injectors for tokamak fueling. Successful installation of such a device would include a protective shell (sabot) to shield the hydrogenic pellet from ablation and allow it to maintain its integrity throughout the acceleration. The SIRENS device has been modified to include specially designed barrel sections equipped with diagnostic ports.

  6. Use of porous aluminosilicate pellets for drug delivery.

    PubMed

    Byrne, R S; Deasy, P B

    2005-06-01

    Three pelletized porous aluminosilicate ceramics were obtained commercially and their potential to act as extended release drug delivery systems was assessed. The pellets were drug loaded using a vacuum impregnation technique. Factors such as the concentration of the loading solution and the porosity and bulk density of the ceramic influenced the drug loading. The release of drug from the pellets was extended as the drug was entrapped within their porous interior. The rate of release was influenced by the porous microstructure of the pellets and the physicochemical properties of the drug. Extrusion-spheronization was used to prepare pellets similar to the porous ceramics. The pellet formulations contained an aluminosilicate clay mineral (kaolin or halloysite), ethylcellulose 100 cps, ethanol and varying quantities of sucrose. The latter two components acted as pore forming agents. Diltiazem HCl was loaded into the pellets and its release was extended. The release rate could be modified by changing the quantity of sucrose included in the initial formulation, as this influenced the porous microstructure of the pellets. In halloysite-based products the release was further extended due to entrapment of the drug within the halloysite microtubules. Porous kaolin-based pellets were also prepared by cryopelletization. This involved freezing droplets of an aqueous suspension containing kaolin, sodium silicate solution and sodium lauryl sulphate. The resulting pellets were freeze-dried, which removed ice from them to leave pores behind. The pellets gave extended drug release with the release rate being influenced by the porous microstructure of the pellets and their microclimate pH.

  7. Researcher Examines Pellets for Micrometeorite Impact Studies

    NASA Image and Video Library

    1959-11-21

    A researcher at the NASA Lewis Research Center manipulates cartridge pellets and a strain gauge target as part of a study on the impact of micrometeorites striking space vehicles. Early in the space program NASA researchers were concerned that small micrometeorites would penetrate spacecraft, injure engines, or damage solar arrays. In response, researchers worked to develop stronger materials to withstand meteorite strikes and screens to block the objects. NASA launched a series of experimental spacecraft into orbit with foil shields that were used to determine the number of meteorite strikes. By the early 1960s the experiments and computer modelling efforts revealed that the micrometeoroid threat was lower than previously anticipated.

  8. A new centrifuge pellet injector for fusion experiments

    NASA Astrophysics Data System (ADS)

    Andelfinger, C.; Buchelt, E.; Cierpka, P.; Kollotzek, H.; Lang, P. T.; Lang, R. S.; Prausner, G.; Söldner, F. X.; Ulrich, M.; Weber, G.

    1993-04-01

    This paper reports on the new pellet injection system for refueling the ASDEX Upgrade tokamak with cubic H2 or D2 pellets having alternative side lengths of 1.5, 1.75, and 2.0 mm and optional Ne doping. The system delivers series of about 100 pellets at a maximum repetition rate of more than 40 Hz. The pellets are accelerated by means of a centrifuge with an optimized straight acceleration arm. This configuration minimizes the compulsive force acting on the pellet during the acceleration process. Since this also minimizes stresses inside the pellet, high velocities—a maximum of 1211 m/s being achieved—are possible without destroying the hydrogen cubes. A special pellet feed-in technique based on a static stop cylinder interrupting the acceleration path successfully reduced the horizontal scattering angle to values of less than ±4°; a high efficiency, with more than 90% of the pellets arriving within the acceptance angle, was thus achieved. The whole system was found to work very reliably and reproducibly during the whole test operation period, covering about 105 pellet shots, and is now being integrated into the ASDEX upgrade experiment.

  9. Impurity pellet injection experiments at TFTR. Final performance report

    SciTech Connect

    Marmar, E.S.

    1992-12-01

    Impurity (Li and C) pellet injection experiments on TFTR have produced a number of new and significant results. (1) We observe reproducible improvements of TFTR supershots after wall-conditioning by Li pellet injection (`lithiumization`). (2) We have made accurate measurements of the pitch angle profiles of the internal magnetic field using two novel techniques. The first measures the internal field pitch from the polarization angles of Li{sup +} line emission from the pellet ablation cloud, while the second measures the pitch angle profiles by observing the tilt of the cigar-shaped Li{sup +} emission region of the ablation cloud. (3) Extensive measurements of impurity pellet penetration into plasmas with central temperatures ranging from {approximately}0.3 to {approximately}7 keV have been made and compared with available theoretical models. Other aspects of pellet cloud physics have been investigated. (4) Using pellets as a well defined perturbation has allowed study of transport phenomena. In the case of small pellet perturbations, the characteristics of the background plasmas are probed, while with large pellets, pellet induced effects are clearly observed. These main results are discussed in more detail in this paper.

  10. New Pellet Injection Schemes on DIII-D

    SciTech Connect

    Anderson, P.M.; Baylor, L.R.; Combs, S.K.; Foust, C.R.; Jernigan, T.C.; Robinson, J.I.

    1999-11-13

    The pellet fueling system on DIII-D has been modified for injection of deuterium pellets from two vertical ports and two inner wall locations on the magnetic high-field side (HFS) of the tokamak. The HFS pellet injection technique was first employed on ASDEX-Upgrade with significant improvements reported in both pellet penetration and fueling efficiency. The new pellet injection schemes on DIII-D required the installation of new guide tubes. These lines are {approx_equal}12.5 m in total length and are made up of complex bends and turns (''roller coaster'' like) to route pellets from the injector to the plasma, including sections inside the torus. The pellet speed at which intact pellets can survive through the curved guide tubes is limited ({approx_equal}200-300 m/s for HFS injection schemes). Thus, one of the three gas guns on the injector was modified to provide pellets in a lower speed regime than the original guns (normal speed range {approx_equal}500 to 1000 m/s). The guide tube installations and gun modifications are described along with the injector operating parameters, and the latest test results are highlighted.

  11. Revealing accumulation zones of plastic pellets in sandy beaches.

    PubMed

    Moreira, Fabiana T; Balthazar-Silva, Danilo; Barbosa, Lucas; Turra, Alexander

    2016-11-01

    Microplastics such as pellets are reported worldwide on sandy beaches, and have possible direct and indirect impacts on the biota and physical characteristics of the habitats where they accumulate. Evaluations of their standing stock at different spatial scales generate data on levels of contamination. This information is needed to identify accumulation zones and the specific beach habitats and communities that are likely to be most affected. Standing stocks of plastic pellets were evaluated in 13 sandy beaches in São Paulo state, Brazil. The sampling strategy incorporated across-shore transects from coastal dunes and backshores, and vertical profiles of the accumulated pellets down to 1 m depth below the sediment surface. Accumulation zones were identified at regional (among beaches) and local (between compartments) scales. At the regional scale pellet density tended to increase at beaches on the central and southwestern coast, near ports and factories that produce and transport the largest amounts of pellets in the country. At the local scale coastal dunes showed larger accumulations of pellets than backshores. For both compartments pellets tended to occur deeper in areas where standing stocks were larger. Most of the pellets were concentrated from the surface down to 0.4 m depth, suggesting that organisms inhabiting this part of the sediment column are more exposed to the risks associated with the presence of pellets. Our findings shed light on the local and regional scales of spatial variability of microplastics and their consequences for assessment and monitoring schemes in coastal compartments.

  12. Fecal pellets: role in sedimentation of pelagic diatoms.

    PubMed

    Schrader, H J

    1971-10-01

    Membrane-enclosed fecal pellets of planktonic herbivores were sampled at several depths in the Baltic Sea (459 meters deep) and off Portugal (4000 meters deep) by means of a Simonsen multinet. Pellets contained mainly empty shells of planktonic diatoms and silicoflagellates. Two kinds of fecal pellets were found, those with the remains of one species (for example, Thalassiosira baltica) and those with the remains of several species (for example, Chaetoceros, Achnanthes, and Thalassiosira). Siliceous skeletons were protected from dissolution during settling by a membrane around the pellet.

  13. Pelletization studies of ultra-fine clean coal

    SciTech Connect

    Mehta, R.H.; Parekh, B.K.

    1995-10-01

    Handling of fine coal is an importance issue for coal as well as the utility industry. Reconstitution in the form of a pellet or briquette would be desirable if it could be done economically. This paper evaluates the effectiveness of three binders e.g., asphalt-emulsion, corn starch and Brewex, in forming pellets of ultra-fine clean coal. It was fond that asphalt emulsion and corn starch were not effective binders for ultra-fine clean coal, however, Brewex provided excellent quality of pellets, which exceeded all the minimum quality requirements of coal pellets.

  14. Pellet fueling development at Oak Ridge National Laboratory

    SciTech Connect

    Foster, C.A.; Milora, S.L.; Schuresko, D.D.; Combs, S.K.; Lunsford, R.V.

    1982-01-01

    A pellet injector development program has been under way at the Oak Ridge National Laboratory (ORNL) since 1976 with the goals of developing D/sub 2/, T/sub 2/ pellet fuel injectors capable of reliable repetitive fueling of reactors and of continued experimentation on contemporary plasma devices. The development has focused primarily on two types of injectors that show promise. One of these injectors is the centrifuge-type injector, which accelerates pellets in a high speed rotating track. The other is the gas or pneumatic gun, which accelerates pellets in a gun barrel using compressed helium of H/sub 2/ gas.

  15. Preparation of (U,Pu)O 2 pellets through sol-gel microsphere pelletization technique

    NASA Astrophysics Data System (ADS)

    Kumar, N.; Pai, Rajesh V.; Joshi, J. K.; Mukerjee, S. K.; Vaidya, V. N.; Venugopal, V.

    2006-12-01

    Mixed uranium-plutonium oxide microspheres were prepared by internal gelation process using feed solution of optimized composition. In the feed, total metal concentration was maintained at 1.5 M and hexamethylenetetramine (HMTA)-urea to metal mole ratio ( R) was kept at 1.0. The gel particles obtained from each batch were dried and heated at 250 °C in air and then calcined in O 2 at 800 °C followed by reduction in 8%H 2/92%N 2 at 600 °C for 1 h to obtain soft (U,Pu)O 2 microspheres containing 4 mol% Pu. The soft (U,Pu)O 2 microspheres were directly taken for the preparation of pellets. The microspheres were characterized with respect to surface area, tap density, crush strength and O/M ratio. X-ray diffraction analysis of the mixed oxide microspheres was carried out to identify the phases. The mixed oxide pellets were characterized for their density and micro-homogeneity. The sintering behaviour was studied by dilatometric investigations. The green pellets were sintered in 8%H 2/92%N 2 at 1600 °C for 2 h. The density of the sintered pellet was found to be 10.40 ± 0.05 g/cm 3 with grains in the size range of 3-6 μm with an excellent micro-homogeneity.

  16. Biocontrol activity and patulin-removal effects of Bacillus subtilis, Rhodobacter sphaeroides and Agrobacterium tumefaciens against Penicillium expansum.

    PubMed

    Wang, Y; Yuan, Y; Liu, B; Zhang, Z; Yue, T

    2016-11-01

    This study was conducted to evaluate the biocontrol potential of Bacillus subtilis CICC 10034, Rhodobacter sphaeroides CGMCC 1.2182 and Agrobacterium tumefaciens CGMCC 1.2554 against patulin (PAT)-producer Penicillium expansum and their ability to remove PAT. Bacillus subtilis effectively inhibited P. expansum both on apples and in in vitro experiments, which reduced the rot diameter on apples by 38% compared with the control. The reduction was followed by those induced by A. tumefaciens (27·63%) and R. sphaeroides (23·67%). None of the cell-free supernatant (CFS) was able to prevent pathogen growth. Three antagonists could suppress PAT production by P. expansum on apples by 98·5, 93·7 and 94·99% after treatment with B. subtilis, R. sphaeroides and A. tumefaciens respectively. In addition, the three strains led to a 0·56-1·47 log CFU g(-1) reduction in colony number of P. expansum on apples. Survival of antagonists on apple wounds revealed their tolerance to PAT. Furthermore, both live and autoclaved cells of three strains efficiently adsorbed artificially spiked PAT from medium. The selected antagonists could be applied before harvesting to control apple infection by PAT-producing fungi and also during processing to act as PAT detoxifiers. Since little information related to the capability of R. sphaeroides and A. tumefaciens to inhibit P. expansum is currently available, the results of this study provide some new perspectives to the biocontrol field. © 2016 The Society for Applied Microbiology.

  17. Bacillus amyloliquefaciens GA1 as a source of potent antibiotics and other secondary metabolites for biocontrol of plant pathogens

    PubMed Central

    2009-01-01

    Background Phytopathogenic fungi affecting crop and post-harvested vegetables are a major threat to food production and food storage. To face these drawbacks, producers have become increasingly dependent on agrochemicals. However, intensive use of these compounds has led to the emergence of pathogen resistance and severe negative environmental impacts. There are also a number of plant diseases for which chemical solutions are ineffective or non-existent as well as an increasing demand by consumers for pesticide-free food. Thus, biological control through the use of natural antagonistic microorganisms has emerged as a promising alternative to chemical pesticides for more rational and safe crop management. Results The genome of the plant-associated B. amyloliquefaciens GA1 was sample sequenced. Several gene clusters involved in the synthesis of biocontrol agents were detected. Four gene clusters were shown to direct the synthesis of the cyclic lipopeptides surfactin, iturin A and fengycin as well as the iron-siderophore bacillibactin. Beside these non-ribosomaly synthetised peptides, three additional gene clusters directing the synthesis of the antibacterial polyketides macrolactin, bacillaene and difficidin were identified. Mass spectrometry analysis of culture supernatants led to the identification of these secondary metabolites, hence demonstrating that the corresponding biosynthetic gene clusters are functional in strain GA1. In addition, genes encoding enzymes involved in synthesis and export of the dipeptide antibiotic bacilysin were highlighted. However, only its chlorinated derivative, chlorotetaine, could be detected in culture supernatants. On the contrary, genes involved in ribosome-dependent synthesis of bacteriocin and other antibiotic peptides were not detected as compared to the reference strain B. amyloliquefaciens FZB42. Conclusion The production of all of these antibiotic compounds highlights B. amyloliquefaciens GA1 as a good candidate for the

  18. Discovery of secondary metabolites from Bacillus spp. biocontrol strains using genome mining and mass spectroscopy

    USDA-ARS?s Scientific Manuscript database

    Genome sequencing, data mining and mass spectrometry were used to identify secondary metabolites produced by several Bacillus spp. biocontrol strains. These biocontrol strains have shown promise in managing Fusarium head blight in wheat. Draft genomes were produced and screened in silico using genom...

  19. Characterization of Two ABC Transporters from Biocontrol and Phytopathogenic Fusarium oxysporus

    USDA-ARS?s Scientific Manuscript database

    ABC transporter genes from four strains of Fusarium oxysporum [two biocontrol and two phytopathogenic (f. sp. lycopersici Race 1) isolates] indicated that this gene is well conserved. However, sequences of promoter regions of FoABC1 differed between 8 phytopathogenic and 11 biocontrol strains of F....

  20. [Effect of agrochemicals and bio-control productions on soil nematode community dynamics].

    PubMed

    Zhang, Wanmin; Duan, Yuxi; Chen, Lijie; Liang, Chen

    2002-05-01

    Dynamics of soil nematode communities amended with agrochemicals and bio-control preparations were investigated in a soybean field. The results showed that the frequency of plant non-parasitic nematodes were obviously higher in soil amended with bio-control preparations (Doufeng 1) than with urea and herbicide, however, that of plant parasitic nematodes exhibited an inverse trend.

  1. Proactive Management of Fermentation and Formulation Interactions to Improve Biocontrol Product Performance

    USDA-ARS?s Scientific Manuscript database

    The key components of biocontrol product development—discovery, fermentation, and formulation—are interactively linked to each other and ultimately to product performance. To identify biocontrol agents suited for commercial development, our discovery programs utilize a cumulative ranking system tha...

  2. Yeast microflora of nectarines and their potential for biocontrol of brown rot

    USDA-ARS?s Scientific Manuscript database

    Resident fruit microflora has been the source of biocontrol agents for the control of postharvest decays of fruits and the active ingredient in commercialized biocontrol products. With the exception of grapes and apples, information on the resident microflora of other fruits is only fragmentary; ho...

  3. Cystofilobasidium infirmominiatum as a biocontrol agent of postharvest diseases of apple and citrus

    USDA-ARS?s Scientific Manuscript database

    Two psycrotrophic yeasts isolated from the surface of lemons have been selected as biocontrol agents of the most common postharvest diseases of apples and citrus that develops during cold storage. The biocontrol yeasts were identified as Cystofilobasidium infirmominiatum and Leucosporidium scottii....

  4. Sex in Fungi

    PubMed Central

    Ni, Min; Feretzaki, Marianna; Sun, Sheng; Wang, Xuying; Heitman, Joseph

    2012-01-01

    Sexual reproduction enables genetic exchange in eukaryotic organisms as diverse as fungi, animals, plants, and ciliates. Given its ubiquity, sex is thought to have evolved once, possibly concomitant with or shortly after the origin of eukaryotic organisms themselves. The basic principles of sex are conserved, including ploidy changes, the formation of gametes via meiosis, mate recognition, and cell-cell fusion leading to the production of a zygote. Although the basic tenants are shared, sex determination and sexual reproduction occur in myriad forms throughout nature, including outbreeding systems with more than two mating types or sexes, unisexual selfing, and even examples in which organisms switch mating type. As robust and diverse genetic models, fungi provide insights into the molecular nature of sex, sexual specification, and evolution to advance our understanding of sexual reproduction and its impact throughout the eukaryotic tree of life. PMID:21942368

  5. Phosphorus recovery using pelletized adsorptive materials ...

    EPA Pesticide Factsheets

    Phosphorous (P) is one of the essential nutrients for growth and is generally the most limiting nutrient since, it cannot be fixed from the atmosphere. Methods for recovering phosphorous from water systems already exist, but advances are being made to find a more economic, efficient, effective and easy to use method that can allow for reuse of the recovered P. One area of study is in adsorption, which involves finding the best material for adsorption of phosphorous from water and for releasing it back into the environment through desorption or leaching. The goal of this research was to first optimize the capacity for a pelletized adsorptive material that was synthesized with varying amounts of a binder material from 0-20 % and then to study recovering the phosphate for reuse. The pelletized materials were studied through kinetics experiments as well as isotherm experiments to gain insight into the adsorption capacity and mechanism. Following successful adsorption, a simple leaching study was conducted to see how much phosphate would be released back into water without any added desorption aid. Desorption was then studied by changing the pH of solution. Presenting my thesis work with a poster at ACS.

  6. Comparison of Ontology Reasoners: Racer, Pellet, Fact++

    NASA Astrophysics Data System (ADS)

    Huang, T.; Li, W.; Yang, C.

    2008-12-01

    In this paper, we examine some key aspects of three of the most popular and effective Semantic reasoning engines that have been developed: Pellet, RACER, and Fact++. While these reasonably advanced reasoners share some notable similarities, it is ultimately the creativity and unique nature of these reasoning engines that have resulted in the successes of each of these reasoners. Of the numerous dissimilarities, the most obvious example might be that while Pellet is written in Java, RACER employs the Lisp programming language and Fact++ was developed using C++. From this and many other distinctions in the system architecture, we can understand the benefits of each reasoner and potentially discover certain properties that may contribute to development of an optimal reasoner in the future. The objective of this paper is to establish a solid comparison of the reasoning engines based on their system architectures, features, and overall performances in real world application. In the end, we expect to produce a valid conclusion about the advantages and problems in each reasoner. While there may not be a decisive first place among the three reasoners, the evaluation will also provide some answers as to which of these current reasoning tools will be most effective in common, practical situations.

  7. The influence of polymeric subcoats and pellet formulation on the release of chlorpheniramine maleate from enteric coated pellets.

    PubMed

    Bruce, L Diane; Koleng, John J; McGinity, James W

    2003-09-01

    The influences of aqueous polymeric subcoats and pellet composition on the release properties of a highly water-soluble drug, chlorpheniramine maleate (CPM), from enteric coated pellets were investigated. Three different aqueous polymeric subcoats, Eudragit RD 100, Eudragit RS 30D, and Opadry AMB, were applied to 10% w/w CPM-loaded pellets that were then enteric coated with Eudragit L 30D-55. Observed drug release from the coated pellets in acidic media correlated with water vapor transmission rates derived for the subcoat films. The influence of pellet composition on retarding the release of CPM from enteric coated pellets in 0.1 N HCl was investigated. The rate of drug release was greatest for pellets prepared with lactose, microcrystalline cellulose, or dibasic calcium phosphate compared with pellets formulated with citric acid and microcrystalline cellulose. Citric acid reduced the pellet micro-environmental pH, decreasing the amount of drug leakage in 0.1 N HCL during the first 2 hr of dissolution. Polymer flocculation was observed when CPM was added to the Eudragit L 30D-55 dispersion. An adsorption isotherm was generated for mixtures of CPM and the polymer and the data were found to fit the Freundlich model for adsorption. Adsorption of CPM to the polymer decreased with the addition of citric acid to the drug-polymer mixtures.

  8. Analysis of Fungal Pellets by UV-Visible Spectrum Diffuse Reflectance Spectroscopy.

    PubMed

    Lestan, D; Podgornik, H; Perdih, A

    1993-12-01

    The application of the UV-visible spectrum diffuse reflectance spectroscopy for the determination of intracellular pH in vivo, for determination of cytochrome content, and for the noninvasive in vivo detection of the redox state of fungal mitochondrial cytochromes in filamentous fungi is introduced. The time course of the intracellular pH values, mitochondrial cytochromes, and CO-binding pigments content and the correlations between the actual redox state of cytochrome aa(3) and saturation of growth medium with oxygen in pellets of the basidiomycete Phanerochaete chrysosporium were determined. As the test microorganism, the yeast Saccharomyces cerevisiae was used. UV-visible spectrum diffuse reflectance spectroscopy proved to be a promising method for the quick and simple analysis of light-impermeable biological structures for which the classical transmittance spectrophotometric methods are difficult to implement.

  9. Tritium proof-of-principle pellet injector: Phase 2

    NASA Astrophysics Data System (ADS)

    Fisher, P. W.; Gouge, M. J.

    1995-03-01

    As part of the International Thermonuclear Engineering Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabricated a pellet injection system to test the mechanical and thermal properties of extruded tritium. This repeating, single-stage, pneumatic injector, called the Tritium-Proof-of-Principle Phase-2 (TPOP-2) Pellet Injector, has a piston-driven mechanical extruder and is designed to extrude hydrogenic pellets sized for the ITER device. The TPOP-II program has the following development goals: evaluate the feasibility of extruding tritium and DT mixtures for use in future pellet injection systems; determine the mechanical and thermal properties of tritium and DT extrusions; integrate, test and evaluate the extruder in a repeating, single-stage light gas gun sized for the ITER application (pellet diameter approximately 7-8 mm); evaluate options for recycling propellant and extruder exhaust gas; evaluate operability and reliability of ITER prototypical fueling systems in an environment of significant tritium inventory requiring secondary and room containment systems. In initial tests with deuterium feed at ORNL, up to thirteen pellets have been extruded at rates up to 1 Hz and accelerated to speeds of order 1.0-1.1 km/s using hydrogen propellant gas at a supply pressure of 65 bar. The pellets are typically 7.4 mm in diameter and up to 11 mm in length and are the largest cryogenic pellets produced by the fusion program to date. These pellets represent about a 11% density perturbation to ITER. Hydrogenic pellets will be used in ITER to sustain the fusion power in the plasma core and may be crucial in reducing first wall tritium inventories by a process called isotopic fueling where tritium-rich pellets fuel the burning plasma core and deuterium gas fuels the edge.

  10. Pathogenicity of Three Entomopathogenic Fungi to Matsucoccus matsumurae

    PubMed Central

    Liu, Weimin; Xie, Yingping; Dong, Jing; Xue, Jiaoliang; Zhang, Yanfeng; Lu, Yaobin; Wu, Jun

    2014-01-01

    Matsucoccus matsumurae (Kuwana) (Hemiptera: Coccoidea: Matsucoccidae) is an invasive alien species and a destructive pest of two native Chinese pines, Pinus tabulaeformis Carr. and P. massoniana Lamb., throughout the eastern regions of China. The pathogenicity of three entomopathogenic fungi, Lecanicillium lecanii strain V3.4504 and V3.4505, Fusarium incarnatum-equiseti strain HEB01 and Lecanicillium fungicola strain HEB02, against M. matsumurae was tested in four instars, to evaluate their potential as a biological control agent. The results showed that the four strains caused disease and death of the scale insect, among which the L. lecanii strains V3.4504 and V3.4505 displayed stronger virulence than the F. incarnatum-equiseti strains HEB01 and L. fungicola strain HEB02 to M. matsumurae in the 2nd-instar nymphs and the adult females. Furthermore, L. lecanii V3.4505 was most virulent to M. matsumurae. The adult females and the male 3rd-instar nymphs of M. matsumurae were susceptible to L. lecanii V3.4505; the adult females were more susceptible at LT50 = 1.96 than the 3rd-instar nymphs at LT50 = 5.67. The body surface structure, cuticle thickness and wax secretions of M. matsumurae impacted the fungal infection. L. lecanii is a promising biocontrol agent, and newly emerged male 3rd-instar nymphs and adult females are a crucial period of the insect’s life cycle for M. matsumurae biocontrol. PMID:25068397

  11. Effect of wheat roots infected with the pathogenic fungus Gaeumannomyces graminis var. tritici on gene expression of the biocontrol bacterium Pseudomonas fluorescens Pf29Arp.

    PubMed

    Barret, Matthieu; Frey-Klett, Pascale; Guillerm-Erckelboudt, Anne-Yvonne; Boutin, Morgane; Guernec, Gregory; Sarniguet, Alain

    2009-12-01

    Traits contributing to the competence of biocontrol bacteria to colonize plant roots are often induced in the rhizosphere in response to plant components. These interactions have been studied using the two partners in gnotobiotic systems. However, in nature, beneficial or pathogenic fungi often colonize roots. Influence of these plant-fungus interactions on bacterial behavior remains to be investigated. Here, we have examined the influence of colonization of wheat roots by the take-all fungus Gaeumannomyces graminis var. tritici on gene expression of the biocontrol bacterium Pseudomonas fluorescens Pf29Arp. Bacteria were inoculated onto healthy, early G. graminis var. tritici-colonized and necrotic roots and transcriptomes were compared by shotgun DNA microarray. Pf29Arp decreased disease severity when inoculated before the onset of necrosis. Necrotic roots exerted a broader effect on gene expression compared with early G. graminis var. tritici-colonized and healthy roots. A gene encoding a putative type VI secretion system effector was only induced in necrotic conditions. A common pool of Pf29Arp genes differentially expressed on G. graminis var. tritici-colonized roots was related to carbon metabolism and oxidative stress, with a highest fold-change with necrosis. Overall, the data showed that the association of the pathogenic fungus with the roots strongly altered Pf29Arp adaptation with differences between early and late G. graminis var. tritici infection steps.

  12. Entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana reduce the survival of Xenopsylla brasiliensis larvae (Siphonaptera: Pulicidae)

    PubMed Central

    2012-01-01

    Background Entomopathogenic fungi, particularly those belonging to the genera Metarhizium and Beauveria have shown great promise as arthropod vector control tools. These agents, however, have not been evaluated against flea vectors of plague. Findings A 3-h exposure to the fungi coated paper at a concentration of 2 × 108 conidia m-2 infected >90% of flea larvae cadavers in the treatment groups. The infection reduced the survival of larvae that had been exposed to fungus relative to controls. The daily risk of dying was four- and over three-fold greater in larvae exposed to M. anisopliae (HR = 4, p<0.001) and B. bassiana (HR = 3.5, p<0.001) respectively. Both fungi can successfully infect and kill larvae of X. brasiliensis with a pooled median survival time (MST±SE) of 2±0.31 days post-exposure. Conclusion These findings justify further research to investigate the bio-control potential of entomopathogenic fungi against fleas. PMID:22992264

  13. A new tritiated water measurement method with plastic scintillator pellets.

    PubMed

    Furuta, Etsuko; Iwasaki, Noriko; Kato, Yuka; Tomozoe, Yusuke

    2016-01-01

    A new tritiated water measurement method with plastic scintillator pellets (PS-pellets) by using a conventional liquid scintillation counter was developed. The PS-pellets used were 3 mm in both diameter and length. A low potassium glass vial was filled full with the pellets, and tritiated water was applied to the vial from 5 to 100 μl. Then, the sample solution was scattered in the interstices of the pellets in a vial. This method needs no liquid scintillator, so no liquid organic waste fluid is generated. The counting efficiency with the pellets was approximately 48 % when a 5 μl solution was used, which was higher than that of conventional measurement using liquid scintillator. The relationship between count rate and activity showed good linearity. The pellets were able to be used repeatedly, so few solid wastes are generated with this method. The PS-pellets are useful for tritiated water measurement; however, it is necessary to develop a new device which can be applied to a larger volume and measure low level concentration like an environmental application.

  14. 21 CFR 520.300b - Cambendazole pellets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Cambendazole pellets. 520.300b Section 520.300b Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.300b Cambendazole pellets....

  15. Unique neuro-ophthalmic presentation of gun pellet injury.

    PubMed

    Sharma, Reena; Sharma, Sanjay; Phuljhele, Swati; Saxena, Rohit

    2016-01-01

    We describe a unique case of orbital gunshot injury with isolated intraorbital pellets lodged symmetrically in the two apices, causing identical clinical presentation, and absence of any associated globe or cerebral injury. He developed bilateral complete third nerve palsy with bilateral traumatic optic neuropathy. The optic nerve strut prevented the pellets from going into the brain on both the sides.

  16. Unique neuro-ophthalmic presentation of gun pellet injury

    PubMed Central

    Sharma, Reena; Sharma, Sanjay; Phuljhele, Swati; Saxena, Rohit

    2016-01-01

    We describe a unique case of orbital gunshot injury with isolated intraorbital pellets lodged symmetrically in the two apices, causing identical clinical presentation, and absence of any associated globe or cerebral injury. He developed bilateral complete third nerve palsy with bilateral traumatic optic neuropathy. The optic nerve strut prevented the pellets from going into the brain on both the sides. PMID:27843239

  17. Co-pelletization of sewage sludge and agricultural wastes.

    PubMed

    Yilmaz, Ersel; Wzorek, Małgorzata; Akçay, Selin

    2017-09-21

    This paper concerns the process of production and properties of pellets based on biomass wastes. Co-pelletization was performed for sewage sludge from municipal wastewater treatment plant and other biomass material such as animal and olive wastes. The aim of the present study was to identify the key factors affecting on the sewage sludge and agricultural residues co-pelletization processes conditions. The impact of raw material type, pellet length, moisture content and particle size on the physical properties was investigated. The technic and technological aspects of co-pelletization were discussed in detail. The physical parameters of pellets, i.e.: drop strength, absorbability and water resistance were determined. Among others, also energy parameters: low and high heat value, content of ash and volatiles were presented. Results showed the range of raw materials moisture, which is necessary to obtain good quality biofuels and also ratio of sewage sludge in pelletizing materials. The analysis of the energetic properties has indicated that the pellet generated on the basis of the sewage sludge and another biomass materials can be applied in the processes of co-combustion with coal. Those biofuels are characterised with properties making them suitable for use in thermal processes and enabling their transport and storage. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Automatic control system for uniformly paving iron ore pellets

    NASA Astrophysics Data System (ADS)

    Wang, Bowen; Qian, Xiaolong

    2014-05-01

    In iron and steelmaking industry, iron ore pellet qualities are crucial to end-product properties, manufacturing costs and waste emissions. Uniform pellet pavements on the grate machine are a fundamental prerequisite to ensure even heat-transfer and pellet induration successively influences performance of the following metallurgical processes. This article presents an automatic control system for uniformly paving green pellets on the grate, via a mechanism mainly constituted of a mechanical linkage, a swinging belt, a conveyance belt and a grate. Mechanism analysis illustrates that uniform pellet pavements demand the frontend of the swinging belt oscillate at a constant angular velocity. Subsequently, kinetic models are formulated to relate oscillatory movements of the swinging belt's frontend to rotations of a crank link driven by a motor. On basis of kinetic analysis of the pellet feeding mechanism, a cubic B-spline model is built for numerically computing discrete frequencies to be modulated during a motor rotation. Subsequently, the pellet feeding control system is presented in terms of compositional hardware and software components, and their functional relationships. Finally, pellet feeding experiments are carried out to demonstrate that the control system is effective, reliable and superior to conventional methods.

  19. 21 CFR 520.300b - Cambendazole pellets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Cambendazole pellets. 520.300b Section 520.300b Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.300b Cambendazole pellets. (a...

  20. 21 CFR 520.300b - Cambendazole pellets.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Cambendazole pellets. 520.300b Section 520.300b Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.300b Cambendazole pellets. (a...

  1. 21 CFR 520.300b - Cambendazole pellets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Cambendazole pellets. 520.300b Section 520.300b Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.300b Cambendazole pellets. (a...

  2. Oxidizing Roasting Performances of Coke Fines Bearing Brazilian Specularite Pellets

    NASA Astrophysics Data System (ADS)

    Chun, Tiejun; Zhu, Deqing

    2016-06-01

    Oxidized pellets, consisting of Brazilian specularite fines and coke fines, were prepared by disc pelletizer using bentonite as binder. The roasting process of pellets includes preheating stage and firing stage. The compressive strength of preheated pellets and fired pellets reached the peak value at 1.5% coke fines dosage. During the initial stage of preheating, some original Fe2O3 was reduced to Fe3O4 because of partial reduction atmosphere in pellet. During the later stage of preheating and firing stage, coke fines were burnt out, and the secondary Fe2O3 (new generation Fe2O3) was generated due to the re-oxidization of Fe3O4, which improved the recrystallization of Fe2O3. Compared with the fired pellets without adding coke fines, fired pellets with 1.5% coke fines exhibited the comparable RSI (reduction swelling index) and RDI+3.15 mm (reduction degradation index), and slightly lower RI (reducibility index).

  3. Integrated management of foot rot of lentil using biocontrol agents under field condition.

    PubMed

    Hannan, M A; Hasan, M M; Hossain, I; Rahman, S M E; Ismail, Alhazmi Mohammed; Oh, Deog-Hwan

    2012-07-01

    The efficacy of cowdung, Bangladesh Institute of Nuclear Agriculture (BINA)-biofertilizer, and Bangladesh Agricultural University (BAU)-biofungicide, alone or in combination, was evaluated for controlling foot rot disease of lentil. The results exhibited that BINA-biofertilizer and BAUbiofungicide (peat soil-based Rhizobium leguminosarum and black gram bran-based Trichoderma harzianum) are compatible and have combined effects in controlling the pathogenic fungi Fusarium oxysporum and Sclerotium rolfsii, which cause the root rot of lentil. Cowdung mixing with soil (at 5 t/ha) during final land preparation and seed coating with BINA-biofertilizer and BAU-biofungicide (at 2.5% of seed weight) before sowing recorded 81.50% field emergence of lentil, which showed up to 19.85% higher field emergence over the control. Post-emergence deaths of plants due to foot rot disease were significantly reduced after combined seed treatment with BINA-biofertilizer and BAU-biofungicide. Among the treatments used, only BAU-biofungicide as the seed treating agent resulted in higher plant stand (84.82%). Use of BINA-biofertilizer and BAU-biofungicide as seed treating biocontrol agents and application of cowdung in the soil as an organic source of nutrient resulted in higher shoot and root lengths, and dry shoot and root weights of lentil. BINA-biofertilizer significantly increased the number of nodules per plant and nodules weight of lentil. Seeds treating with BAUbiofungicide and BINA-biofertilizer and soil amendment with cowdung increased the biomass production of lentil up to 75.56% over the control.

  4. Paraformaldehyde pellet not necessary in vacuum-pumped maple sap system

    Treesearch

    H. Clay Smith; Carter B. Gibbs

    1970-01-01

    In a study of sugar maple sap collection through a vacuum-pumped plastic tubing system, yields were compared between tapholes in which paraformaldehyde pellets were used and tapholes without pellets, Use of the pellets did not increase yield.

  5. Biocontrol in an impulsive predator-prey model.

    PubMed

    Terry, Alan J

    2014-10-01

    We study a model for biological pest control (or "biocontrol") in which a pest population is controlled by a program of periodic releases of a fixed yield of predators that prey on the pest. Releases are represented as impulsive increases in the predator population. Between releases, predator-pest dynamics evolve according to a predator-prey model with some fairly general properties: the pest population grows logistically in the absence of predation; the predator functional response is either of Beddington-DeAngelis type or Holling type II; the predator per capita birth rate is bounded above by a constant multiple of the predator functional response; and the predator per capita death rate is allowed to be decreasing in the predator functional response and increasing in the predator population, though the special case in which it is constant is permitted too. We prove that, when the predator functional response is of Beddington-DeAngelis type and the predators are not sufficiently voracious, then the biocontrol program will fail to reduce the pest population below a particular economic threshold, regardless of the frequency or yield of the releases. We prove also that our model possesses a pest-eradication solution, which is both locally and globally stable provided that predators are sufficiently voracious and that releases occur sufficiently often. We establish, curiously, that the pest-eradication solution can be locally stable whilst not being globally stable, the upshot of which is that, if we delay a biocontrol response to a new pest invasion, then this can change the outcome of the response from pest eradication to pest persistence. Finally, we state a number of specific examples for our model, and, for one of these examples, we corroborate parts of our analysis by numerical simulations.

  6. Plant biomass degradation by fungi.

    PubMed

    Mäkelä, Miia R; Donofrio, Nicole; de Vries, Ronald P

    2014-11-01

    Plant biomass degradation by fungi has implications for several fields of science. The enzyme systems employed by fungi for this are broadly used in various industrial sectors such as food & feed, pulp & paper, detergents, textile, wine, and more recently biofuels and biochemicals. In addition, the topic is highly relevant in the field of plant pathogenic fungi as they degrade plant biomass to either gain access to the plant or as carbon source, resulting in significant crop losses. Finally, fungi are the main degraders of plant biomass in nature and as such have an essential role in the global carbon cycle and ecology in general. In this review we provide a global view on the development of this research topic in saprobic ascomycetes and basidiomycetes and in plant pathogenic fungi and link this to the other papers of this special issue on plant biomass degradation by fungi. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Straw pellets as fuel in biomass combustion units

    SciTech Connect

    Andreasen, P.; Larsen, M.G.

    1996-12-31

    In order to estimate the suitability of straw pellets as fuel in small combustion units, the Danish Technological Institute accomplished a project including a number of combustion tests in the energy laboratory. The project was part of the effort to reduce the use of fuel oil. The aim of the project was primarily to test straw pellets in small combustion units, including the following: ash/slag conditions when burning straw pellets; emission conditions; other operational consequences; and necessary work performance when using straw pellets. Five types of straw and wood pellets made with different binders and antislag agents were tested as fuel in five different types of boilers in test firings at 50% and 100% nominal boiler output.

  8. ["Piggyback" shot: ballistic parameters of two simultaneously discharged airgun pellets].

    PubMed

    Frank, Matthias; Schönekess, Holger C; Grossjohann, Rico; Ekkernkamp, Axel; Bockholdt, Britta

    2014-01-01

    Green and Good reported an uncommon case of homicide committed with an air rifle in 1982 (Am. J. Forensic Med. Pathol. 3: 361-365). The fatal wound was unusual in that two airgun pellets were loaded in so-called "piggyback" fashion into a single shot air rifle. Lack of further information on the ballistic characteristics of two airgun pellets as opposed to one conventionally loaded projectile led to this investigation. The mean kinetic energy (E) of the two pellets discharged in "piggyback" fashion was E = 3.6 J and E = 3.4 J, respectively. In comparison, average kinetic energy values of E = 12.5 J were calculated for conventionally discharged single diabolo pellets. Test shots into ballistic soap confirmed the findings of a single entrance wound as reported by Green and Good. While the ballistic background of pellets discharged in "piggyback" fashion could be clarified, the reason behind this mode of shooting remains unclear.

  9. Studies on Pellet Fueling of ITER-Like Plasmas

    SciTech Connect

    Kamelander, Gerald; Weimann, Geert; Garzotti, Luca; Litaudon, Xavier; Moreau, Didier; Pegourie, Bernard

    2004-06-15

    The paper reports on simulation of pellet-fueled plasmas in a fusion reactor. The simulations have been performed by means of the ASTRA transport code. We have studied physical modeling of pellet injection as well as the numerical conditions to resolve pellet injection correctly. As a first step the essential mechanisms for density control have been studied based on simplified assumptions with a generic source of additional heating. The experience gained has been used to simulate advanced scenarios including internal transport barriers. It has been confirmed that it is possible to drive the plasma of a next-generation tokamak into a high-Q regime and to maintain it in a steady-state regime. Nevertheless, the pellet injection parameters required are rather demanding and imply a significant technological improvement of pellet injectors. Those investigations represent an improvement of simulations done earlier with a control of the central density at constant profile.

  10. Analysis of pellet properties with use of artificial neural networks.

    PubMed

    Mendyk, Aleksander; Kleinebudde, Peter; Thommes, Markus; Yoo, Angelina; Szlęk, Jakub; Jachowicz, Renata

    2010-11-20

    The objective was to prepare neural models identifying relationships between formulation characteristics and pellet properties based on algorithmic approach of crucial variables selection and neuro-fuzzy systems application. The database consisted of information about 227 pellet formulations prepared by extrusion/spheronization method, with various model drugs and excipients. Cheminformatic description of excipients and model drugs was employed for numerical description of pellet formulations. Initial numbers of neural model inputs were up to around 3000. The inputs reduction procedure based on sensitivity analysis allowed to obtain less than 40 inputs for each model. The reduced models were subjects of fuzzy logic implementation resulting in logical rules tables providing human-readable rule sets applicable in future development of pellet formulations. Neural modeling enhanced knowledge about pelletization process and provided means for future computer-guided search for the optimal formulation.

  11. Calculation of density profiles in tandem mirrors fueled by pellets

    SciTech Connect

    Campbell, R.B.; Gilmore, J.M.

    1983-12-02

    We have modified the LLNL radial transport code TMT to model reactor regime plasmas, fueled by pellets. The source profiles arising from pellet fueling are obtained from existing pellet ablation models. Because inward radial diffusion due to inverted profiles must compete with trapping of central cell ions in the transition region for tandem mirrors, pellets must penetrate fairly far into the plasma. In fact, based on our radial calculations, a pellet with a velocity of 10 km/sec cannot sustain the central flux tubes; a velocity more like 100 km/sec will be necessary. We also find that the central cell radial diffusion must exceed classical by about a factor of 100.

  12. Transport and MHD simulations of intrinsic and pellet induced ELMs

    NASA Astrophysics Data System (ADS)

    Kim, Ki Min; Na, Yong-Su; Yi, Sumin; Kim, Hyunseok; Kim, Jin Yong

    2010-11-01

    Verification of ELM mechanism and demonstration of ELM control are important issues in current fusion researches targeting ITER and DEMO. This work investigates the physics and operational characteristics of intrinsic and pellet induced ELMs throughout transport simulations using 1.5 D transport codes (C1.5/ASTRA) and MHD simulations using M3D code. Transport simulations are focused on prediction of the global parameters such as ELM energy loss in the type-I ELMy H-mode discharges with and without pellet pace making to examine an applicability of pellet injection for ELM mitigation in KSTAR and ITER. On the other hand, MHD simulations are conducted to explore the physics of intrinsic and pellet induced ELMs by applying the artificial free energy sources of velocity stream and density perturbations on the marginally stable equilibrium, respectively. Similarities and differences of triggering phenomena between intrinsic and pellet induced ELMs are discussed from the MHD approach.

  13. Fabrication of very high density fuel pellets of thorium dioxide

    NASA Astrophysics Data System (ADS)

    Shiratori, Tetsuo; Fukuda, Kosaku

    1993-06-01

    Very high density ThO 2 pellets were prepared without binders and lubricants from the ThO 2 powder originated by the thorium oxalate, which was aimed to simplify the fabrication process by skipping a preheat treatment. The as-received ThO 2 powder with a surface area of 4.56 m 2/g was ball-milled up to about 9 m 2/g in order to increase the green pellet density as high as possible. Both of the single-sided and the double-sided pressing were tested in the range from 2 to 5 t/cm 2 in the green pellet formation. Sintering temperature was such low as 1550°C. The pellet prepared in this experiment had a very high density in the range from about 96 to 98% TD without any cracks, in which a difference of the pellet density was not recognized in the single-sided pressing methods.

  14. Modulation of Human Immune Response by Fungal Biocontrol Agents

    PubMed Central

    Konstantinovas, Cibele; de Oliveira Mendes, Tiago A.; Vannier-Santos, Marcos A.; Lima-Santos, Jane

    2017-01-01

    Although the vast majority of biological control agents is generally regarded as safe for humans and environment, the increased exposure of agriculture workers, and consumer population to fungal substances may affect the immune system. Those compounds may be associated with both intense stimulation, resulting in IgE-mediated allergy and immune downmodulation induced by molecules such as cyclosporin A and mycotoxins. This review discusses the potential effects of biocontrol fungal components on human immune responses, possibly associated to infectious, inflammatory diseases, and defective defenses. PMID:28217107

  15. Modulation of Human Immune Response by Fungal Biocontrol Agents.

    PubMed

    Konstantinovas, Cibele; de Oliveira Mendes, Tiago A; Vannier-Santos, Marcos A; Lima-Santos, Jane

    2017-01-01

    Although the vast majority of biological control agents is generally regarded as safe for humans and environment, the increased exposure of agriculture workers, and consumer population to fungal substances may affect the immune system. Those compounds may be associated with both intense stimulation, resulting in IgE-mediated allergy and immune downmodulation induced by molecules such as cyclosporin A and mycotoxins. This review discusses the potential effects of biocontrol fungal components on human immune responses, possibly associated to infectious, inflammatory diseases, and defective defenses.

  16. A Foray into Fungal Ecology: Understanding Fungi and Their Functions Across Ecosystems

    NASA Astrophysics Data System (ADS)

    Francis, N.; Dunkirk, N. C.; Peay, K.

    2015-12-01

    Despite their incredible diversity and importance to terrestrial ecosystems, fungi are not included in a standard high school science curriculum. This past summer, however, my work for the Stanford EARTH High School Internship program introduced me to fungal ecology through experiments involving culturing, genomics and root dissections. The two fungal experiments I worked on had very different foci, both searching for answers to broad ecological questions of fungal function and physiology. The first, a symbiosis experiment, sought to determine if the partners of the nutrient exchange between pine trees and their fungal symbionts could choose one another. The second experiment, a dung fungal succession project, compared the genetic sequencing results of fungal extractions from dung versus fungal cultures from dung. My part in the symbiosis experiment involved dissection, weighing and encapsulation of root tissue samples characterized based on the root thickness and presence of ectomycorrhizal fungi. The dung fungi succession project required that I not only learn how to culture various genera of dung fungi but also learn how to extract DNA and RNA for sequencing from the fungal tissue. Although I primarily worked with dung fungi cultures and thereby learned about their unique physiologies, I also learned about the different types of genetic sequencing since the project compared sequences of cultured fungi versus Next Generation sequencing of all fungi present within a dung pellet. Through working on distinct fungal projects that reassess how information about fungi is known within the field of fungal ecology, I learned not only about the two experiments I worked on but also many past related experiments and inquiries through reading scientific papers. Thanks to my foray into fungal research, I now know not only the broader significance of fungi in ecological research but also how to design and conduct ecological experiments.

  17. Pelletizing/reslurrying as a means of distributing and firing clean coal

    SciTech Connect

    Not Available

    1992-06-09

    This volume contains appendices for: atomization test report; cost estimation model--pelletization material balance and equipment selection; cost estimation model--pelletization capital investment estimates; cost estimation--pelletization operating cost estimates; cost estimation model--pellet-CWF formulation material balance and equipment selection; cost estimation model--pellet-CWF capital investment estimates; cost estimation model--pellet-CWF operating cost estimates; and cost estimation model--direct CWF operating cost estimates.

  18. Tritium pellet injector for the Tokamak Fusion Test Reactor

    SciTech Connect

    Gouge, M.J.; Baylor, L.R.; Combs, S.K.; Fisher, P.W.; Foust, C.R.; Milora, S.L.

    1992-01-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) plasma phase. An existing deuterium pellet injector (DPI) was modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed for frozen pellets ranging in size from 3 to 4 mm in diameter in arbitrarily programmable firing sequences at tritium pellet speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller (PLC). The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were also made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed and the TPI was tested at ORNL with deuterium pellets. Results of the testing program at ORNL are described. The TPI has been installed and operated on TFTR in support of the CY-92 deuterium plasma run period. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and tritium gloveboxes and integrated into TFTR tritium processing systems to provide full tritium pellet capability.

  19. Tritium pellet injector for the Tokamak Fusion Test Reactor

    SciTech Connect

    Gouge, M.J.; Baylor, L.R.; Combs, S.K.; Fisher, P.W.; Foust, C.R.; Milora, S.L.

    1992-11-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) plasma phase. An existing deuterium pellet injector (DPI) was modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed for frozen pellets ranging in size from 3 to 4 mm in diameter in arbitrarily programmable firing sequences at tritium pellet speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller (PLC). The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were also made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed and the TPI was tested at ORNL with deuterium pellets. Results of the testing program at ORNL are described. The TPI has been installed and operated on TFTR in support of the CY-92 deuterium plasma run period. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and tritium gloveboxes and integrated into TFTR tritium processing systems to provide full tritium pellet capability.

  20. Solar drying of yam-flour pellets

    SciTech Connect

    Oladiran, M.T.

    1987-01-01

    An experimental investigation of the heat/mass transfer characteristics of a turbulent impinging jet in cross flow in a model of a chamber used for solar drying of yam flour pellets is presented. The variables studied were the nozzle inclination, ..cap alpha.. and the jet-to-cross flow velocity ratio, M. These parameters were varied from 30/sup 0/ to 135/sup 0/ and from 5.0 to 20.9 respectively. Superimposing a cross flow onto the jet reduced the heat transfer coefficients. At low cross flows, inclining the nozzle further reduced the heat transfer coefficients. However, at higher cross flows, inclining the nozzle could be beneficial. The thin film napthalene sublimation technique was employed for the mass transfer measurements.

  1. U.S. Pellet Industry Analysis

    SciTech Connect

    Corrie I. Nichol; Jacob J. Jacobsen; Richard D. Boardman

    2011-06-01

    This report is a survey of the U.S. Pellet Industry, its current capacity, economic drivers, and projected demand for biomass pellets to meet future energy consumption needs. Energy consumption in the US is projected to require an ever increasing portion of renewable energy sources including biofuels, among which are wood, and agrictulrual biomass. Goals set by federal agencies will drive an ever increasing demand for biomass. The EIA projections estimate that renewable energy produced by 2035 will be roughly 10% of all US energy consumption. Further analysis of the biofuels consumption in the US shows that of the renewable energy sources excluding biofuels, nearly 30% are wood or biomass waste. This equates to roughly 2% of the total energy consumption in the US coming from biomass in 2009, and the projections for 2035 show a strong increase in this amount. As of 2009, biomass energy production equates to roughly 2-2.5 quadrillion Btu. The EIA projections also show coal as providing 21% of energy consumed. If biomass is blended at 20% to co-fire coal plants, this will result in an additional 4 quadrillion Btu of biomass consumption. The EISA goals aim to produce 16 billion gal/year of cellulosic biofuels, and the US military has set goals for biofuels production. The Air Force has proposed to replace 50% of its domestic fuel requirements with alternative fuels from renewable sources by 2016. The Navy has likewise set a goal to provide 50% of its energy requirements from alternative sources. The Department of Energy has set similarly ambitious goals. The DOE goal is to replace 40% of 2004 gasoline use with biofuels. This equates to roughly 60 billion gal/year, of which, 45 billion gal/year would be produced from lignocellulosic resources. This would require 530 million dry tons of herbaceous and woody lignocellulosic biomass per year.

  2. Comparison of film-coated retarded release pellets manufactured by layering technique or by bed rotor pelletization.

    PubMed

    Priese, Florian; Frisch, Toni; Wolf, Bertram

    2015-06-01

    In order to investigate the influence of coatings for controlled active pharmaceutical ingredient (API) release, two types of pellets were used. Microcrystalline pellets were coated with a model API using the Wurster fluidized bed technique in laboratory scale (layered Cellets). Another type of pellets consisting of microcrystalline cellulose and model API was manufactured by fluidized bed rotor pelletization (matrix pellets (MP)). Both kinds of pellets were coated in a Wurster fluidized bed process with a polymer mixture of ethylcellulose to achieve retarded API release. With layered Cellets and an increased thickness of the ethylcellulose layer, the lag-time was increased and the release rate was decreased. In the case of MP, retardation was less pronounced probable due to inhomogeneous polymer film formation as a result of the porous particle surface. To reduce the surface roughness, the MP were coated with polyvinylpyrrolidone (PVP) as an intermediate smoothing layer, in a first trial step by step. In a second trial, pelletization and the coating steps were performed in an uninterrupted process. Intermediate PVP coating improved the ethylcellulose film formation and led to a more pronounced retardation of API release. The uninterrupted process of matrix pellet manufacturing and coating results in a product with only low retarded release.

  3. Development of Impregnated Agglomerate Pelletization (IAP) process for fabrication of (Th,U)O 2 mixed oxide pellets

    NASA Astrophysics Data System (ADS)

    Khot, P. M.; Nehete, Y. G.; Fulzele, A. K.; Baghra, Chetan; Mishra, A. K.; Afzal, Mohd.; Panakkal, J. P.; Kamath, H. S.

    2012-01-01

    Impregnated Agglomerate Pelletization (IAP) technique has been developed at Advanced Fuel Fabrication Facility (AFFF), BARC, Tarapur, for manufacturing (Th, 233U)O 2 mixed oxide fuel pellets, which are remotely fabricated in hot cell or shielded glove box facilities to reduce man-rem problem associated with 232U daughter radionuclides. This technique is being investigated to fabricate the fuel for Indian Advanced Heavy Water Reactor (AHWR). In the IAP process, ThO 2 is converted to free flowing spheroids by powder extrusion route in an unshielded facility which are then coated with uranyl nitrate solution in a shielded facility. The dried coated agglomerate is finally compacted and then sintered in oxidizing/reducing atmosphere to obtain high density (Th,U)O 2 pellets. In this study, fabrication of (Th,U)O 2 mixed oxide pellets containing 3-5 wt.% UO 2 was carried out by IAP process. The pellets obtained were characterized using optical microscopy, XRD and alpha autoradiography. The results obtained were compared with the results for the pellets fabricated by other routes such as Coated Agglomerate Pelletization (CAP) and Powder Oxide Pelletization (POP) route.

  4. Circular economy in drinking water treatment: reuse of ground pellets as seeding material in the pellet softening process.

    PubMed

    Schetters, M J A; van der Hoek, J P; Kramer, O J I; Kors, L J; Palmen, L J; Hofs, B; Koppers, H

    2015-01-01

    Calcium carbonate pellets are produced as a by-product in the pellet softening process. In the Netherlands, these pellets are applied as a raw material in several industrial and agricultural processes. The sand grain inside the pellet hinders the application in some high-potential market segments such as paper and glass. Substitution of the sand grain with a calcite grain (100% calcium carbonate) is in principle possible, and could significantly improve the pellet quality. In this study, the grinding and sieving of pellets, and the subsequent reuse as seeding material in pellet softening were tested with two pilot reactors in parallel. In one reactor, garnet sand was used as seeding material, in the other ground calcite. Garnet sand and ground calcite performed equally well. An economic comparison and a life-cycle assessment were made as well. The results show that the reuse of ground calcite as seeding material in pellet softening is technologically possible, reduces the operational costs by €38,000 (1%) and reduces the environmental impact by 5%. Therefore, at the drinking water facility, Weesperkarspel of Waternet, the transition from garnet sand to ground calcite will be made at full scale, based on this pilot plant research.

  5. Biology of gut anaerobic fungi.

    PubMed

    Bauchop, T

    1989-01-01

    The obligately anaerobic nature of the gut indigenous fungi distinguishes them from other fungi. They are distributed widely in large herbivores, both in the foregut of ruminant-like animals and in the hindgut of hindgut fermenters. Comparative studies indicate that a capacious organ of fermentative digestion is required for their development. These fungi have been assigned to the Neocallimasticaceae, within the chytridiomycete order Spizellomycetales. The anaerobic fungi of domestic ruminants have been studied most extensively. Plant material entering the rumen is rapidly colonized by zoospores that attach and develop into thalli. The anaerobic rumen fungi have been shown to produce active cellulases and xylanases and specifically colonise and grow on plant vascular tissues. Large populations of anaerobic fungi colonise plant fragment in the rumens of cattle and sheep on high-fibre diets. The fungi actively ferment cellulose which results in formation of a mixture of products including acetate, lactate, ethanol, formate, succinate, CO2 and H2. The properties of the anaerobic fungi together with the extent of their populations on plant fragments in animals on high-fibre diets indicates a significant role for the fungi in fibre digestion.

  6. Communication in Fungi

    PubMed Central

    Cottier, Fabien; Mühlschlegel, Fritz A.

    2012-01-01

    We will discuss fungal communication in the context of fundamental biological functions including mating, growth, morphogenesis, and the regulation of fungal virulence determinants. We will address intraspecies but also interkingdom signaling by systematically discussing the sender of the message, the molecular message, and receiver. Analyzing communication shows the close coevolution of fungi with organisms present in their environment giving insights into multispecies communication. A better understanding of the molecular mechanisms underlying microbial communication will promote our understanding of the “fungal communicome.” PMID:21961006

  7. Fusarium and other opportunistic hyaline fungi

    USDA-ARS?s Scientific Manuscript database

    This chapter focuses on those fungi that grow in tissue in the form of hyaline or lightly colored septate hyphae. These fungi include Fusarium and other hyaline fungi. Disease caused by hyaline fungi is referred to as hyalohyphomycosis. Hyaline fungi described in this chapter include the anamorphic,...

  8. Isolation of oxalic acid tolerating fungi and decipherization of its potential to control Sclerotinia sclerotiorum through oxalate oxidase like protein.

    PubMed

    Yadav, Shivani; Srivastava, Alok K; Singh, Dhanajay P; Arora, Dilip K

    2012-11-01

    Oxalic acid plays major role in the pathogenesis by Sclerotinia sclerotiorum; it lowers the pH of nearby environment and creates the favorable condition for the infection. In this study we examined the degradation of oxalic acid through oxalate oxidase and biocontrol of Sclerotinia sclerotiorum. A survey was conducted to collect the rhizospheric soil samples from Indo-Gangetic Plains of India to isolate the efficient fungal strains able to tolerate oxalic acid. A total of 120 fungal strains were isolated from root adhering soils of different vegetable crops. Out of 120 strains a total of 80 isolates were able to grow at 10 mM of oxalic acid whereas only 15 isolates were grow at 50 mM of oxalic acid concentration. Then we examined the antagonistic activity of the 15 isolates against Sclerotinia sclerotiorum. These strains potentially inhibit the growth of the test pathogen. A total of three potential strains and two standard cultures of fungi were tested for the oxalate oxidase activity. Strains S7 showed the maximum degradation of oxalic acid (23 %) after 60 min of incubation with fungal extract having oxalate oxidase activity. Microscopic observation and ITS (internally transcribed spacers) sequencing categorized the potential fungal strains into the Aspergillus, Fusarium and Trichoderma. Trichoderma sp. are well studied biocontrol agent and interestingly we also found the oxalate oxidase type activity in these strains which further strengthens the potentiality of these biocontrol agents.

  9. Suppression of the root-knot nematode [Meloidogyne incognita (Kofoid & White) Chitwood] on tomato by dual inoculation with arbuscular mycorrhizal fungi and plant growth-promoting rhizobacteria.

    PubMed

    Liu, Runjin; Dai, Mei; Wu, Xia; Li, Min; Liu, Xingzhong

    2012-05-01

    Arbuscular mycorrhizal (AM) fungi and plant growth-promoting rhizobacteria (PGPR) have potential for the biocontrol of soil-borne diseases. The objectives of this study were to quantify the interactions between AM fungi [Glomus versiforme (Karsten) Berch and Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe] and PGPR [Bacillus polymyxa (Prazmowski) Mace and Bacillus sp.] during colonization of roots and rhizosphere of tomato (Lycopersicon esculentum Mill) plants (cultivar Jinguan), and to determine their combined effects on the root-knot nematode, Meloidogyne incognita, and on tomato growth. Three greenhouse experiments were conducted. PGPR increased colonization of roots by AM fungi, and AM fungi increased numbers of PGPR in the rhizosphere. Dual inoculations of AM fungi plus PGPR provided greater control of M. incognita and greater promotion of plant growth than single inoculations, and the best combination was G. mosseae plus Bacillus sp. The results indicate that specific AM fungi and PGPR can stimulate each other and that specific combinations of AM fungi and PGPR can interact to suppress M. incognita and disease development.

  10. Biocontrol of postharvest Rhizopus decay of peaches with Pichia caribbica.

    PubMed

    Xu, Baitian; Zhang, Hongyin; Chen, Keping; Xu, Qin; Yao, Yao; Gao, Hui

    2013-08-01

    A new yeast antagonist, Pichia caribbica, isolated in our laboratory from the soil collected from unsprayed orchards, was evaluated for its biocontrol capability against Rhizopus stolonifer on peaches and the possible mechanisms involved. The decay incidence and lesion diameter of Rhizopus decay of peaches treated by P. caribbica were significantly reduced compared with the control fruits, and the higher the concentration of P. caribbica, the better the efficacy of the biocontrol. Rapid colonization of the yeast in peach wounds stored at 25 °C was observed. In peaches, the activities of peroxidase (POD), catalase (CAT), and phenylalanine ammonia-lyase (PAL) were significantly induced by P. caribbica treatment compared to those of the control fruits. All these results indicated that P. caribbica has a great potential for the development of commercial formulations to control postharvest Rhizopus decay of peaches. Its modes of action were based on competition for space and nutrients with pathogens, inducement of activities of defense-related enzymes such as POD, CAT, and PAL of peaches.

  11. Indigenous bacteria may interfere with the biocontrol of plant diseases

    NASA Astrophysics Data System (ADS)

    Someya, Nobutaka; Akutsu, Katsumi

    2009-06-01

    Prodigiosin is a reddish antibiotic pigment that plays an important role in the biocontrol of plant diseases by the bacterium Serratia marcescens. However, its activity is unstable under agricultural conditions; further, it can be degraded by various environmental factors. To examine the effect of epiphytic microbes on the stability of prodigiosin used for biological control processes, we collected a total of 1,280 bacterial isolates from the phylloplane of cyclamen and tomato plants. Approximately 72% of the bacterial strains isolated from the cyclamen plants and 66% of those isolated from the tomato plants grew on minimal agar medium containing 100 μg ml-1 prodigiosin. Certain isolates obtained from both plant species exhibited prodigiosin-degrading activity. We compared the 16S rRNA gene sequences derived from the isolates with sequences in a database. The comparison revealed that the sequences determined for the prodigiosin-degrading isolates were homologous to those of the genera Pseudomonas, Caulobacter, Rhizobium, Sphingomonas, Janthinobacterium, Novosphingobium, and Rathayibacter. These results indicate that indigenous epiphytic microorganisms may interfere with the interaction between plant pathogens and biocontrol agents by degrading the antibiotics produced by the agents.

  12. Pyrolysis of ground pine chip and ground pellet particles

    DOE PAGES

    Rezaei, Hamid; Yazdanpanah, Fahimeh; Lim, C. Jim; ...

    2016-08-04

    In addition to particle size, biomass density influences heat and mass transfer rates during the thermal treatment processes. In this research, thermal behaviour of ground pine chip particles and ground pine pellet particles in the range of 0.25–5 mm was investigated. A single particle from ground pellets was almost 3 to 4 times denser than a single particle from ground chips at a similar size and volume of particle. Temperature was ramped up from room temperature (~25 °C) to 600 °C with heating rates of 10, 20, 30, and 50 °C/min. Pellet particles took 25–88 % longer time to drymore » than the chip particles. Microscopic examination of 3 mm and larger chip particles showed cracks during drying. No cracks were observed for pellet particles. The mass loss due to treatment at temperatures higher than 200 °C was about 80% both for chip and pellet particles. It took 4 min for chip and pellet particles to lose roughly 63% of their dry mass at a heating rate of 50 °C/min. The SEM structural analysis showed enlarged pores and cracks in cell walls of the pyrolyzed wood chips. As a result, these pores were not observed in pyrolyzed pellet particles.« less

  13. Pyrolysis of ground pine chip and ground pellet particles

    SciTech Connect

    Rezaei, Hamid; Yazdanpanah, Fahimeh; Lim, C. Jim; Lau, Anthony; Sokhansanj, Shahab

    2016-08-04

    In addition to particle size, biomass density influences heat and mass transfer rates during the thermal treatment processes. In this research, thermal behaviour of ground pine chip particles and ground pine pellet particles in the range of 0.25–5 mm was investigated. A single particle from ground pellets was almost 3 to 4 times denser than a single particle from ground chips at a similar size and volume of particle. Temperature was ramped up from room temperature (~25 °C) to 600 °C with heating rates of 10, 20, 30, and 50 °C/min. Pellet particles took 25–88 % longer time to dry than the chip particles. Microscopic examination of 3 mm and larger chip particles showed cracks during drying. No cracks were observed for pellet particles. The mass loss due to treatment at temperatures higher than 200 °C was about 80% both for chip and pellet particles. It took 4 min for chip and pellet particles to lose roughly 63% of their dry mass at a heating rate of 50 °C/min. The SEM structural analysis showed enlarged pores and cracks in cell walls of the pyrolyzed wood chips. As a result, these pores were not observed in pyrolyzed pellet particles.

  14. Formulation of immediate release pellets containing famotidine solid dispersions

    PubMed Central

    Ibrahim, Mohamed Abbas; El-Badry, Mahmoud

    2013-01-01

    Famotidine (FM) is a potent H2-receptor antagonist used for the treatment of peptic ulcer. It has a low and variable bioavailability which is attributed to its low water solubility. In this study, the dissolution of the drug was enhanced by a preparation of solid dispersion using two hydrophilic carriers, namely Gelucire 50/13 and Pluronic F-127. The prepared solid dispersions were characterized by differential scanning calorimetry (DSC), which indicated that there were no signs of interaction of the drug with the carriers used in the case of solid dispersions containing higher polymeric contents (1:3 and 1:5). FM solid dispersions in the matrices of Gelucire 50/13 and Pluronic F-127 (1:3) were used to prepare pellets. The scanning electron microscope (SEM) images of pellets showed that the pellets have spherical shape and their size depends on the carrier used. The dissolution of the drug from either solid dispersion or pellets was performed. The dissolution study depicted that, the presence of the drug in solid dispersion enhanced its dissolution in comparison with the drug itself. Also, the drug release from the manufactured pellets was found to be improved in the case of solid dispersions (drug:carrier 1:3). A complete drug release occurred after 30 min from pellets containing solid dispersions, while only about 30% of the loaded FM was released from pellets containing untreated drug after 2 h. PMID:24648827

  15. Microplastic resin pellets on an urban tropical beach in Colombia.

    PubMed

    Acosta-Coley, Isabel; Olivero-Verbel, Jesus

    2015-07-01

    Microplastics are a problem in oceans worldwide. The current situation in Latin America is not well known. This paper reports, for the first time, the presence of microplastics on an urban Caribbean beach in Cartagena, Colombia. Pellet samples were collected from a tourist beach over a 5-month period covering both dry and rainy seasons. Pellets were classified by color and their surface analyzed by stereomicroscopy, and some were characterized by infrared spectroscopy. The most abundant pellets were white, presenting virgin surfaces, with few signs of oxidation. This is congruent with a short residence time in the marine environment and primary sources possibly located nearby. The frequency of white pellets did not change with sampling period. Surface features identified in the pellets included cracks, material loss, erosion, adhesion, granulation, color change, and glazed surfaces. Reticulated granular pellets exhibited the greatest degradation, easily generating submicroplastics. Sample composition was mostly polyethylene, followed by polypropylene. This pollution problem must be addressed by responsible authorities to avoid pellet deposition in oceans and on beaches around the world.

  16. Pyrolysis of ground pine chip and ground pellet particles

    SciTech Connect

    Rezaei, Hamid; Yazdanpanah, Fahimeh; Lim, C. Jim; Lau, Anthony; Sokhansanj, Shahab

    2016-08-04

    In addition to particle size, biomass density influences heat and mass transfer rates during the thermal treatment processes. In this research, thermal behaviour of ground pine chip particles and ground pine pellet particles in the range of 0.25–5 mm was investigated. A single particle from ground pellets was almost 3 to 4 times denser than a single particle from ground chips at a similar size and volume of particle. Temperature was ramped up from room temperature (~25 °C) to 600 °C with heating rates of 10, 20, 30, and 50 °C/min. Pellet particles took 25–88 % longer time to dry than the chip particles. Microscopic examination of 3 mm and larger chip particles showed cracks during drying. No cracks were observed for pellet particles. The mass loss due to treatment at temperatures higher than 200 °C was about 80% both for chip and pellet particles. It took 4 min for chip and pellet particles to lose roughly 63% of their dry mass at a heating rate of 50 °C/min. The SEM structural analysis showed enlarged pores and cracks in cell walls of the pyrolyzed wood chips. As a result, these pores were not observed in pyrolyzed pellet particles.

  17. Consolidated waste forms: glass marbles and ceramic pellets

    SciTech Connect

    Treat, R.L.; Rusin, J.M.

    1982-05-01

    Glass marbles and ceramic pellets have been developed at Pacific Northwest Laboratory as part of the multibarrier concept for immobilizing high-level radioactive waste. These consolidated waste forms served as substrates for the application of various inert coatings and as ideal-sized particles for encapsulation in protective matrices. Marble and pellet formulations were based on existing defense wastes at Savannah River Plant and proposed commercial wastes. To produce marbles, glass is poured from a melter in a continuous stream into a marble-making device. Marbles were produced at PNL on a vibratory marble machine at rates as high as 60 kg/h. Other marble-making concepts were also investigated. The marble process, including a lead-encapsulation step, was judged as one of the more feasible processes for immobilizing high-level wastes. To produce ceramic pellets, a series of processing steps are required, which include: spray calcining - to dry liquid wastes to a powder; disc pelletizing - to convert waste powders to spherical pellets; sintering - to densify pellets and cause desired crystal formation. These processing steps are quite complex, and thereby render the ceramic pellet process as one of the least feasible processes for immobilizing high-level wastes.

  18. Fecal Pellet Flux in the Mesopelagic Sargasso Sea

    NASA Astrophysics Data System (ADS)

    Koweek, D.; Shatova, O.; Conte, M. H.; Weber, J. C.

    2010-12-01

    The Oceanic Flux Program (OFP), located 75km SE of Bermuda, is the longest running sediment trap time-series of its kind, continually collecting deep sea particle flux since 1978. Recent application of digital microphotography to the size-fractionated OFP sediment trap material has generated a wealth of new quantitative visual information on particle flux composition, its changes with depth, and its temporal variability. We examined the fecal pellet flux at 1500m depth using image analysis of digital archives, in conjunction with data on the overlying surface ocean from the Bermuda Testbed Mooring (BTM) and the Bermuda Atlantic Time Series (BATS) programs, to investigate the role of mesoscale physical forcing on mesopelagic particle flux variability. During 2007, a productive cyclonic eddy, a mode water eddy and an anticyclonic eddy passed over the OFP site. Fecal pellet flux was enhanced during passage of both the cyclonic and mode water eddies. Total mass flux (TMF) was also enhanced during the productive cyclonic eddy, but was not influenced by the passage of the mode water eddy. No increase in fecal pellet flux or TMF was apparent during passage of the anticyclonic eddy despite indications of increased zooplankton abundance from ADCP backscatter intensity. Fecal pellet size frequency distributions indicate the presence of two, and sometimes three, distinct size classes. No seasonal trend in mean size of fecal pellets was observed for any size class, implying that the size distribution of the zooplankton populations producing the pellets is relatively constant throughout the year. We also investigated fecal pellet flux changes with depth at 500, 1500 and 3200m. Fecal pellet flux, and the fecal pellet contribution to TMF, were greatest at 500m and decreased with depth. The use of quantitative image analysis holds great potential as a powerful analytical tool in studies of marine particulate flux.

  19. Characterization of fly ash ceramic pellet for phosphorus removal.

    PubMed

    Li, Shiyang; Cooke, Richard A; Wang, Li; Ma, Fang; Bhattarai, Rabin

    2017-03-15

    Phosphorus has been recognized as a leading pollutant for surface water quality deterioration. In the Midwestern USA, subsurface drainage not only provides a pathway for excess water to leave the field but it also drains out nutrients like nitrogen (N) and phosphorus (P). Fly ash has been identified as one of the viable materials for phosphorus removal from contaminated waters. In this study, a ceramic pellet was manufactured using fly ash for P absorption. Three types of pellet with varying lime and clay proportions by weight (type 1: 10% lime + 30% clay, type 2: 20% lime + 20% clay, and type 3: 30% lime + 10% clay) were characterized and evaluated for absorption efficiency. The result showed that type 3 pellet (60% fly ash with 30% lime and 10% clay) had the highest porosity (14%) and absorption efficiency and saturated absorption capacity (1.98 mg P/g pellet) compared to type 1 and 2 pellets. The heavy metal leaching was the least (30 μg/L of chromium after 5 h) for type 3 pellet compared to other two. The microcosmic structure of pellet from scanning electron microscope showed the type 3 pellet had the better distribution of aluminum and iron oxide on the surface compared other two pellets. This result indicates that addition of lime and clay can improve P absorption capacity of fly ash while reducing the potential to reduce chromium leaching. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Molecular Systematics of Entomopathogenic Fungi

    USDA-ARS?s Scientific Manuscript database

    Insect parasitism has multiple and diverse origins within the Kingdom Fungi, with shifts to trophic specialization on insects having evolved one or more times in each of the four traditionally recognized phyla of fungi, the Ascomycota, Basidiomycota, Chytridiomycota, and Zygomycota. The rich legacy ...

  1. Metabolomics protocols for filamentous fungi.

    PubMed

    Gummer, Joel P A; Krill, Christian; Du Fall, Lauren; Waters, Ormonde D C; Trengove, Robert D; Oliver, Richard P; Solomon, Peter S

    2012-01-01

    Proteomics and transcriptomics are established functional genomics tools commonly used to study filamentous fungi. Metabolomics has recently emerged as another option to complement existing techniques and provide detailed information on metabolic regulation and secondary metabolism. Here, we describe broad generic protocols that can be used to undertake metabolomics studies in filamentous fungi.

  2. ECCENTRIC ROLLING OF POWDER AND BONDING AGENT INTO SPHERICAL PELLETS

    DOEpatents

    Patton, G. Jr.; Zirinsky, S.

    1961-06-01

    A machine is described for pelletizing powder and bonding agent into spherical pellets of high density and uniform size. In this device, the material to be compacted is added to a flat circular pan which is moved in a circular orbit in a horizontal plane about an axis displaced from that of the pan's central axis without rotating the pan about its central axis. This movement causes the material contained therein to roll around the outside wall of the container and build up pellets of uniform shape, size, and density.

  3. Fast imaging of intact and shattered cryogenic neon pellets.

    PubMed

    Wang, Zhehui; Combs, S K; Baylor, L R; Foust, C R; Lyttle, M S; Meitner, S J; Rasmussen, D A

    2014-11-01

    Compact condensed-matter injection technologies are increasingly used in magnetic fusion. One recent application is in disruption mitigation. An imaging system with less-than-100-µm- and sub-µs-resolution is described and used to characterize intact and shattered cryogenic neon pellets. Shattered pellets contain fine particles ranging from tens of µm to about 7 mm. Time-of-flight analyses indicate that pellets could slow down if hitting the wall of the guide tube. Fast high-resolution imaging systems are thus useful to neon and other condensed-matter injector development.

  4. Fast Imaging of Intact and Shattered Cryogenic Neon Pellets

    SciTech Connect

    Wang, Zhehui; Combs, Stephen Kirk; Baylor, Larry R; Foust, Charles R; Lyttle, Mark S; Meitner, Steven J; Rasmussen, David A

    2014-01-01

    Compact condensed-matter injection technologies are increasingly used in magnetic fusion. One recent application is in disruption mitigation. An imaging system with less-than-100- m- and sub- s-resolution is described and used to characterize intact and shattered cryogenic neon pellets. Shattered pellets contain fine particles ranging from tens of m to about 7 mm. Time-of-flight analyses indicate that pellets could slow down if hitting the wall of the guide tube. Fast high-resolution imaging systems are thus useful to neon and other condensed-matter injector development.

  5. Fast imaging of intact and shattered cryogenic neon pellets

    SciTech Connect

    Wang, Zhehui; Combs, S. K.; Baylor, L. R.; Foust, C. R.; Lyttle, M. S.; Meitner, S. J.; Rasmussen, D. A.

    2014-11-15

    Compact condensed-matter injection technologies are increasingly used in magnetic fusion. One recent application is in disruption mitigation. An imaging system with less-than-100-µm- and sub-µs-resolution is described and used to characterize intact and shattered cryogenic neon pellets. Shattered pellets contain fine particles ranging from tens of µm to about 7 mm. Time-of-flight analyses indicate that pellets could slow down if hitting the wall of the guide tube. Fast high-resolution imaging systems are thus useful to neon and other condensed-matter injector development.

  6. Cleaning By Blasting With Pellets Of Dry Ice

    NASA Technical Reports Server (NTRS)

    Fody, Jody

    1993-01-01

    Dry process strips protective surface coats from parts to be cleaned, without manual scrubbing. Does not involve use of flammable or toxic solvents. Used to remove coats from variety of materials, including plastics, ceramics, ferrous and nonferrous metals, and composites. Adds no chemical-pollution problem to problem of disposal of residue of coating material. Process consists of blasting solid carbon dioxide (dry ice) pellets at surface to be cleaned. Pellets sublime on impact and pass into atmosphere as carbon dioxide gas. Size, harness, velocity, and quantity of pellets adjusted to suit coating material and substrate.

  7. Sm1, a proteinaceous elicitor secreted by the biocontrol fungus Trichoderma virens induces plant defense responses and systemic resistance.

    PubMed

    Djonović, Slavica; Pozo, Maria J; Dangott, Lawrence J; Howell, Charles R; Kenerley, Charles M

    2006-08-01

    The soilborne filamentous fungus Trichoderma virens is a biocontrol agent with a well-known ability to produce antibiotics, parasitize pathogenic fungi, and induce systemic resistance in plants. Even though a plant-mediated response has been confirmed as a component of bioprotection by Trichoderma spp., the molecular mechanisms involved remain largely unknown. Here, we report the identification, purification, and characterization of an elicitor secreted by T. virens, a small protein designated Sm1 (small protein 1). Sm1 lacks toxic activity against plants and microbes. Instead, native, purified Sm1 triggers production of reactive oxygen species in monocot and dicot seedlings, rice, and cotton, and induces the expression of defense-related genes both locally and systemically in cotton. Gene expression analysis revealed that SM1 is expressed throughout fungal development under different nutrient conditions and in the presence of a host plant. Using an axenic hydroponic system, we show that SM1 expression and secretion of the protein is significantly higher in the presence of the plant. Pretreatment of cotton cotyledons with Sm1 provided high levels of protection to the foliar pathogen Colletotrichum sp. These results indicate that Sm1 is involved in the induction of resistance by Trichoderma spp. through the activation of plant defense mechanisms.

  8. Potential of Epicoccum purpurascens Strain 5615 AUMC as a Biocontrol Agent of Pythium irregulare Root Rot in Three Leguminous Plants

    PubMed Central

    Koutb, Mostafa

    2010-01-01

    Epicoccum purpurascens stain 5615 AUMC was investigated for its biocontrol activity against root rot disease caused by Pythium irregulare. E. purpurascens greenhouse pathogenicity tests using three leguminous plants indicated that the fungus was nonpathogenic under the test conditions. The germination rate of the three species of legume seeds treated with a E. purpurascens homogenate increased significantly compared with the seeds infested with P. irregulare. No root rot symptoms were observed on seeds treated with E. purpurascens, and seedlings appeared more vigorous when compared with the non-treated control. A significant increase in seedling growth parameters (seedling length and fresh and dry weights) was observed in seedlings treated with E. purpurascens compared to pathogen-treated seedlings. Pre-treating the seeds with the bioagent fungus was more efficient for protecting seeds against the root rot disease caused by P. irregulare than waiting for disease dispersal before intervention. To determine whether E. purpurascens produced known anti-fungal compounds, an acetone extract of the fungus was analyzed by gas chromatography mass spectrometry. The extract revealed a high percentage of the cinnamic acid derivative (trimethylsiloxy) cinnamic acid methyl ester. The E. purpurascens isolate grew more rapidly than the P. irregulare pathogen in a dual culture on potato dextrose agar nutrient medium, although the two fungi grew similarly when cultured separately. This result may indicate antagonism via antibiosis or competition. PMID:23956668

  9. Tomato progeny inherit resistance to the nematode Meloidogyne javanica linked to plant growth induced by the biocontrol fungus Trichoderma atroviride

    PubMed Central

    Medeiros, Hugo Agripino de; Araújo Filho, Jerônimo Vieira de; Freitas, Leandro Grassi de; Castillo, Pablo; Rubio, María Belén; Hermosa, Rosa; Monte, Enrique

    2017-01-01

    Root-knot nematodes (RKN) are major crop pathogens worldwide. Trichoderma genus fungi are recognized biocontrol agents and a direct activity of Trichoderma atroviride (Ta) against the RKN Meloidogyne javanica (Mj), in terms of 42% reduction of number of galls (NG), 60% of number of egg masses and 90% of number of adult nematodes inside the roots, has been observed in tomato grown under greenhouse conditions. An in vivo split-root designed experiment served to demonstrate that Ta induces systemic resistance towards Mj, without the need for the organisms to be in direct contact, and significantly reduces NG (20%) and adult nematodes inside tomato roots (87%). The first generation (F1) of Ta-primed tomato plants inherited resistance to RKN; although, the induction of defenses occurred through different mechanisms, and in varying degrees, depending on the Ta-Mj interaction. Plant growth promotion induced by Ta was inherited without compromising the level of resistance to Mj, as the progeny of Ta-primed plants displayed increased size and resistance to Mj without fitness costs. Gene expression results from the defense inductions in the offspring of Ta-primed plants, suggested that an auxin-induced reactive oxygen species production promoted by Ta may act as a major defense strategy during plant growth. PMID:28071749

  10. Biological control of sheep gastrointestinal nematodiasis in a tropical region of the southeast of Brazil with the nematode predatory fungi Duddingtonia flagrans and Monacrosporium thaumasium.

    PubMed

    Silva, Andre R; Araújo, Jackson V; Braga, Fabio R; Frassy, Luiza N; Tavela, Alexandre O; Carvalho, Rogerio O; Castejon, Fernanda V

    2009-11-01

    Formulations in matrix of sodium alginate (pellets) of the nematode predatory fungi Duddingtonia flagrans and Monacrosporium thaumasium were evaluated in the biological control of sheep gastrointestinal nematodiasis. Three groups (1, 2, and 3), each one with eight sheep of the Santa Inês breed, at the ages of 15-48 months, were placed in paddocks of Brachiaria decumbens for 5 months. In group 1, each animal received 1 g/10 kg of live weight (l.w.) of pellets of D. flagrans (0.2 g of fungus/10 kg l.w.). In group 2, each animal received 1 g/10 kg of l.w. of pellets of the fungus M. thaumasium (0.2 g of fungus/10 kg l.w.), twice a week, for 5 months. In group 3 (control), the animals received 1 g/10 kg of live weight of pellets without fungus. The monthly averages of the egg countings per gram of feces of the animals of groups 1 and 2 treated were 71.6% and 61.1% smaller, respectively, in comparison to the animals of group 3 (control). The treatment of sheep with pellets containing the nematophagous fungi D. flagrans and M. thaumasium may be used as an alternative for the control of sheep gastrointestinal nematodiasis.

  11. Liquid cultivation techniques for enhancing the effectiveness of yeast biocontrol agents

    USDA-ARS?s Scientific Manuscript database

    Biocontrol agents will gain broader acceptance into integrated pest management programs if products with enhanced efficacy and consistency of performance are developed. Though given comparatively little research attention, liquid cultivation environments and protocols can and should be optimized to...

  12. Proactive management of fermentation and formulation interactions to improve biocontrol product performance

    USDA-ARS?s Scientific Manuscript database

    The key components of biocontrol product development; discovery, fermentation, and formulation, are interactively linked to each other and ultimately, to product performance. The fermentation environment can be managed to maximize the quantity and quality of biomass and bioproducts produced which, ...

  13. Phyllostictines A-D, Oxazatricycloalkenones Produced by Phyllosticta cirsii, A Potential Mycoherbicide for Cirsium arvense Biocontrol

    USDA-ARS?s Scientific Manuscript database

    Phyllosticta cirsii, a fungal pathogen isolated from Cirsium arvense and proposed as biocontrol agent of this noxious perennial weed, produces in liquid cultures different phytotoxic metabolites with potential herbicidal activity. Four new oxazatricycloalkenones, named phyllostictines A-D, were isol...

  14. Risk assessment: progress of quarantine biocontrol research on Chinese Tallow, Melaleuca, and Downy Rose Myrtle

    USDA-ARS?s Scientific Manuscript database

    Risk assessments of two biocontrol candidates for Chinese tallow, Triadica sebifera (Euphoriales: Euphorbiaceae), and one for Melaleuca, Melaleuca quinquenervia (Myrtales: Myrtaceae), were conducted during 2009 and continuing into 2010 by USDA scientists located at the Florida Department of Agricul...

  15. Alternative Bioenergy: Small Scale Pellet Production from Forest Residues

    NASA Astrophysics Data System (ADS)

    Cochran, Audra S.

    Forests can readily supply feedstock for alternative bioenergy production. Feedstock removal has the potential to benefit forest health and provide ecosystem services, while also generating profit for landowners, contractors and forest managers. However, many landowners are faced with the challenge of managing forest residuals to meet slash compliances and fire regulations. Currently, most residuals are burned or left on site to decompose. Every year, the north-central Idaho region produces over 16 million dry tons of unutilized forest residues. In a time where alternative energy sources are growing in demand, new approaches to utilize these residuals for bioenergy production are being examined. One approach is a portable, small-scale wood pellet mill that can be taken directly to the logging site. Utilizing forest residues for pellet production reduces residue burning and its potential negative impacts on air quality. This presentation focuses on the quality of wood pellets manufactured by a portable wood pellet mill utilizing various forms of forest residuals.

  16. Solvent-free cleaning using a centrifugal cryogenic pellet accelerator

    SciTech Connect

    Haines, J.R.; Fisher, P.W.; Foster, C.A.

    1995-06-01

    An advanced centrifuge that accelerates frozen CO{sub 2} pellets to high speeds for surface cleaning and paint removal is being developed at the Oak Ridge National Laboratory. The centrifuge-based accelerator was designed, fabricated, and tested under a program sponsored by the Warner Robins Air Logistics Center, Robins Air Force Base, Georgia. In comparison to the more conventional compressed air ``sandblast`` pellet accelerators, the centrifugal accelerator system can achieve higher pellet speeds, has precise speed control, and is more than ten times as energy efficient. Furthermore, the use of frozen CO{sub 2} pellets instead of conventional metal, plastic, sand, or other abrasive materials that remain solid at room temperature, minimizes the waste stream. This apparatus has been used to demonstrate cleaning of various surfaces, including removal of paint, oxide coatings, metal coatings, organic coatings, and oil and grease coatings from a variety of surfaces. The design and operation of the apparatus is discussed.

  17. Effects of pelletized anticoagulant rodenticides on California quail

    USGS Publications Warehouse

    Blus, L.J.; Henny, C.J.; Grove, R.A.

    1985-01-01

    A moribund, emaciated California quail (Callipepla californica) that was found in an orchard in the state of Washington had an impacted crop and gizzard. Pellets containing the anticoagulant chlorophacinone (Rozol, RO) were in the crop; the gizzard contents consisted of a pink mass of paraffin that was selectively accumulated from the paraffinized pellets. The plasma prothrombin time of 28 sec was near that determined for control quail. The signs of RO intoxication seen in the moribund wild quail were duplicated in captive quail given ad libitum diets of either RO or another paraffinized chlorophacinone pellet (Mr. Rat Guard II, MRG). This left little doubt that paraffin impaction of the gizzard was the primary problem. All captive quail fed RO or MRG pellets showed no increases in prothrombin times compared to control values, died in an emaciated condition, and had gizzards impacted with paraffin.

  18. Smoothed Particle Hydrodynamic Simulation of Iron Ore Pellets Flow

    SciTech Connect

    Gustafsson, G.; Haeggblad, H.-A.; Oldenburg, M.

    2007-05-17

    In this work the Smoothed Particle Hydrodynamics (SPH) method is used to simulate iron ore pellets flow. A continuum material model describing the yield strength, elastic and plastic parameters for pellets as a granular material is used in the simulations. The most time consuming part in the SPH method is the contact search of neighboring nodes at each time step. In this study, a position code algorithm for the contact search is presented. The cost of contact searching for this algorithm is of the order of Nlog2N, where N is the number of nodes in the system. The SPH-model is used for simulation of iron ore pellets silo flow. A two dimensional axisymmetric model of the silo is used in the simulations. The simulation results are compared with data from an experimental cylindrical silo, where pellets are discharged from a concentric outlet. Primary the flow pattern is compared.

  19. Stability behaviour of molsidomine-containing pellet formulations.

    PubMed

    Laicher, A; Jünger, H; Klemm, F H

    1997-02-01

    Molsidomine in mixtures with different inactive ingredients has been subjected to a stability test. The fingerprint chromatogram obtained by HPLC with diode-array detection of mixtures of molsidomine with povidone 25 revealed decomposition products; the detection wavelength of 210 nm resulted in easy detection of the degradation products. Molsidomine-containing pellets were manufactured according to a compact procedure and by applying the active ingredient to placebo pellets. Compared with the nonpareil pellet formulations, compact pellets have a considerably higher water content and undergo decomposition of the active ingredient after storage for 50 months under different conditions. It is assumed that the decomposition of molsidomine is accelerated by the peroxide found in povidone.

  20. Feed Pellet and Corn Durability and Breakage During Repeated Elevator Handling

    USDA-ARS?s Scientific Manuscript database

    Pelleting of animal feeds is important for improved feeding efficiency and for convenience of handling. Pellet quality impacts the feeding benefits for the animals and pellet integrity during handling. To determine the effect of repeated handling on feed pellet breakage and durability, a 22.6-t (100...

  1. Cesium powder and pellets inner container decontamination method determination

    SciTech Connect

    Ferrell, P.C.

    1998-07-09

    The cesium powder and pellets inner container is to be performance tested per the criteria specified in Section 4.0 of HNF-2399, ``Design, Fabrication, and Assembly Criteria for Cesium Powder and Pellet Inner Container.`` The test criteria specifies that the inner container be water tight during decontamination of the exterior surface. Three prototypes will be immersed into a pool of water to simulate a water decontamination process.

  2. Nuclear fuel pellet quality control using artificial intelligence techniques

    NASA Astrophysics Data System (ADS)

    Song, Xiaolong

    Inspection of nuclear fuel pellets is a complex and time-consuming process. At present, quality control in the fuel fabrication field mainly relies on human manual inspection, which is essentially a judgement call. Considering the high quality requirement of fuel pellets in the nuclear industry, pellet inspection systems must have a high accuracy rate in addition to a high inspection speed. Furthermore, any inspection process should have a low rejection rate of good pellets from the manufacturer point of view. It is very difficult to use traditional techniques, such as simple image comparison, to adequately perform the inspection process of the nuclear fuel pellet. Knowledge-based inspection and a defect-recognition algorithm, which maps the human inspection knowledge, is more robust and effective. A novel method is introduced here for pellet image processing. Three artificial intelligence techniques are studied and applied for fuel pellet inspection in this research. They are an artificial neural network, fuzzy logic, and the decision tree method. A dynamic reference model is located on each input fuel pellet image. Then, those pixels that belong to the abnormal defect are enhanced with high speed and high accuracy. Next, the content-based features for the defect are extracted from those abno1mal pixels and used in the inspection algorithm. Finally, an automated inspection prototype system---Visual Inspection Studio---which combines machine vision and these three AI techniques, is developed and tested. The experimental results indicate a very successful system with a high potential for on-line automatic inspection process.

  3. QUALITY OF WOOD PELLETS PRODUCED IN BRITISH COLUMBIA FOR EXPORT

    SciTech Connect

    Tumuluru, J.S.; Sokhansanj, Shahabaddine; Lim, C. Jim; Bi, X.T.; Lau, A.K.; Melin, Staffan; Oveisi, E.; Sowlati, T.

    2010-11-01

    Wood pellet production and its use for heat and power production are increasing worldwide. The quality of export pellets has to consistently meet certain specifications as stipulated by the larger buyers, such as power utilities or as specified by the standards used for the non-industrial bag market. No specific data is available regarding the quality of export pellets to Europe. To develop a set of baseline data, wood pellets were sampled at an export terminal in Vancouver, British Columbia, Canada. The sampling period was 18 months in 2007-2008 when pellets were transferred from storage bins to the ocean vessels. The sampling frequency was once every 1.5 to 2 months for a total of 9 loading/shipping events. The physical properties of the wood pellets measured were moisture content in the range of 3.5% to 6.5%, bulk density from 728 to 808 kg/m3, durability from 97% to 99%, fines content from 0.03% to 0.87%, calorific value as is from 17 to almost 18 MJ/kg, and ash content from 0.26% to 0.93%.The diameter and length were in the range of 6.4 to 6.5 mm and 14.0 to 19.0 mm, respectively. All of these values met the published non-industrial European grades (CEN) and the grades specified by the Pellet Fuel Institute for the United States for the bag market. The measured values for wood pellet properties were consistent except the ash content values decreased over the test period.

  4. Quality of Wood Pellets Produced in British Columbia for Export

    SciTech Connect

    J. S. Tumuluru; S. Sokhansanj; C. J. Lim; T. Bi; A. Lau; S. Melin; T. Sowlati; E. Oveisi

    2010-11-01

    Wood pellet production and its use for heat and power production are increasing worldwide. The quality of export pellets has to consistently meet certain specifications as stipulated by the larger buyers, such as power utilities or as specified by the standards used for the non-industrial bag market. No specific data is available regarding the quality of export pellets to Europe. To develop a set of baseline data, wood pellets were sampled at an export terminal in Vancouver, British Columbia, Canada. The sampling period was 18 months in 2007-2008 when pellets were transferred from storage bins to the ocean vessels. The sampling frequency was once every 1.5 to 2 months for a total of 9 loading/shipping events. The physical properties of the wood pellets measured were moisture content in the range of 3.5% to 6.5%, bulk density from 728 to 808 kg/m3, durability from 97% to 99%, fines content from 0.03% to 0.87%, calorific value as is from 17 to almost 18 MJ/kg, and ash content from 0.26% to 0.93%.The diameter and length were in the range of 6.4 to 6.5 mm and 14.0 to 19.0 mm, respectively. All of these values met the published non-industrial European grades (CEN) and the grades specified by the Pellet Fuel Institute for the United States for the bag market. The measured values for wood pellet properties were consistent except the ash content values decreased over the test period.

  5. Measurement of persistent organic pollutants (POPs) in plastic resin pellets from remote islands: toward establishment of background concentrations for International Pellet Watch.

    PubMed

    Heskett, Marvin; Takada, Hideshige; Yamashita, Rei; Yuyama, Masaki; Ito, Maki; Geok, Yeo Bee; Ogata, Yuko; Kwan, Charita; Heckhausen, Angelika; Taylor, Heidi; Powell, Taj; Morishige, Carey; Young, Doug; Patterson, Hugh; Robertson, Bryson; Bailey, Elizabeth; Mermoz, Jorge

    2012-02-01

    Plastic resin pellets collected from remote islands in the Pacific, Atlantic, and Indian Oceans and the Caribbean Sea were analyzed for polychlorinated biphenyls (PCBs), dichloro-diphenyltrichloroethane and its degradation products (DDTs), and hexachlorocyclohexanes (HCHs). Concentrations of PCBs (sum of 13 congeners) in the pellets were 0.1-9.9 ng/g-pellet. These were 1-3 orders of magnitude smaller than those observed in pellets from industrialized coastal shores. Concentrations of DDTs in the pellets were 0.8-4.1 ng/g-pellet. HCH concentrations were 0.6-1.7 ng/g-pellet, except for 19.3 ng/g-pellet on St. Helena, where current use of lindane is likely influence. This study provides background levels of POPs (PCBs<10 ng/g-pellet, DDTs <4 ng/g-pellet, HCHs <2 ng/g-pellet) for International Pellet Watch. Sporadic large concentrations of POPs were found in some pellet samples from remote islands and should be considered in future assessments of pollutants on plastic debris.

  6. Pelletization of biomass waste with potato pulp content

    NASA Astrophysics Data System (ADS)

    Obidziński, Sławomir

    2014-03-01

    This paper presents the results of a research on the influence of potato pulp content in a mixture with oat bran on the power demand of the pelletization process and on the quality of the produced pellets, in the context of use thereof as a heating fuel. The tests of the densification of the pulp and bran mixture were carried out on a work stand whose main element was a P-300 pellet mill with the `flat matrix-densification rolls' system. 24 h after the pellets left the working system, their kinetic durability was established with the use of a Holmen tester. The research results obtained in this way allowed concluding that increasing the potato pulp content in a mixture with oat bran from 15 to 20% caused a reduction of the power demand of the pellet mill. It was also established that as the pulp content in a mixture with oat bran increases from 15 to 25%, the value of the kinetic durability of the pellets determined using Holmen and Pfost methods decreases.

  7. A Gyrotron-Powered Pellet Accelerator for Tokamak Fueling

    NASA Astrophysics Data System (ADS)

    Parks, P. B.; Perkins, F. W.

    2006-04-01

    A novel pellet acceleration concept [1] using microwave power from MW gyrotron sources has been developed that could pave the way for high-speed >3 km/s inner-wall pellet injection on ITER-class tokamaks. The concept is based on the principal of a gun, where a high-pressure propellant gas drives the projectile down the barrel. In the proposed concept, the high gas pressure is created by evaporative explosion of a composite ``pusher'' medium attached behind the DT fuel pellet. The pusher consists of micron-sized conducting particles, (Li, Be, C) embedded uniformly in a D2 ice slug with <5% volume concentration, thus facilitating microwave energy absorption by dissipation of eddy currents flowing within the conducting particles only. Microwave power is delivered to the pusher along a waveguide, which also serves as the pellet launch tube. A scaling law predicts that a pellet of mass M accelerated over a distance L reaches a velocity v (PL/M)^1/3, where P is the gyrotron power.pard[1] P. Parks & F. Perkins, US patent application ``Microwave-Powered Pellet Accelerator,'' No. 11/256/662, October 21, 2005.

  8. Results of hydrogen pellet injection into ISX-B

    SciTech Connect

    Milora, S.L.; Foster, C.A.; Thomas, C.E.

    1980-09-01

    High speed pellet fueling experiments have been performed on the ISX-B device in a new regime characterized by large global density rise in both ohmic and neutral beam heated discharges. Hydrogen pellets of 1 mm in diameter were injected in the plasma midplane at velocities exceeding 1 km/s. In low temperature ohmic discharges, pellets penetrate beyond the magnetic axis, and in such cases a sharp decrease in ablation is observed as the pellet passes the plasma center. Density increases of approx. 300% have been observed without degrading plasma stability or confinement. Energy confinement time increases in agreement with the empirical scaling tau/sub E/ approx. n/sub e/ and central ion temperature increases as a result of improved ion-electron coupling. Laser-Thomson scattering and radiometer measurements indicate that the pellet interaction with the plasma is adiabatic. Penetration to r/a approx. 0.15 is optimal, in which case large amplitude sawtooth oscillations are observed and the density remains elevated. Gross plasma stability is dependent roughly on the amount of pellet penetration and can be correlated with the expected temporal evolution of the current density profile.

  9. Modeling operation mode of pellet boilers for residential heating

    NASA Astrophysics Data System (ADS)

    Petrocelli, D.; Lezzi, A. M.

    2014-11-01

    In recent years the consumption of wood pellets as energy source for residential heating lias increased, not only as fuel for stoves, but also for small-scale residential boilers that, produce hot water used for both space heating and domestic hot water. Reduction of fuel consumption and pollutant emissions (CO, dust., HC) is an obvious target of wood pellet boiler manufacturers, however they are also quite interested in producing low- maintenance appliances. The need of frequent maintenance turns in higher operating costs and inconvenience for the user, and in lower boiler efficiency and higher emissions also. The aim of this paper is to present a theoretical model able to simulate the dynamic behavior of a pellet boiler. The model takes into account many features of real pellet boilers. Furthermore, with this model, it is possible to pay more attention to the influence of the boiler control strategy. Control strategy evaluation is based not only on pellet consumption and on total emissions, but also on critical operating conditions such as start-up and stop or prolonged operation at substantially reduced power level. Results are obtained for a residential heating system based on a wood pellet boiler coupled with a thermal energy storage. Results obtained so far show a weak dependence of performance in terms of fuel consumption and total emissions on control strategy, however some control strategies present some critical issues regarding maintenance frequency.

  10. A Compact Flexible Pellet Injection System for Fueling Studies

    NASA Astrophysics Data System (ADS)

    Baylor, L. R.; Combs, S. K.; Fehling, D. T.; Fisher, P. W.; Foust, C. R.; Gouge, M. J.; Rasmussen, D. A.

    2000-10-01

    A compact pellet injection system is being designed and built at ORNL to provide a flexible pellet fueling system for studies in magnetic confinement fusion devices. The system known as a ``pellet injector in a suitcase (PIS)'' is a pipe gun device with four barrels that uses a cryocooler for in-situ hydrogenic pellet formation. The system is being built to provide a flexible, low-cost fueling system that can be used on a number of plasma confinement experiments with minimal installation and operation costs. components in the system. It will use both propellant gas and a mechanical punch to accelerate the 1 - 4 mm size pellets to 100-1500 m/s. With the mechanical punch alone a low speed pellet, useful for curved guide tube applications, can be produced with minimal gas load eliminating the need for a large ballast volume. can be independently fired. diagnose the injector. The PIS is a flexible tool for fueling alternative concept devices such as MST and NSTX and for specialized studies in mainline tokamak experiments such as DIII-D and JET. The small size makes installation on such devices more feasible. of the system design and the expected performance will be presented.

  11. Evaluating the ignition sensitivity of thermal battery heat pellets

    SciTech Connect

    Thomas, E.V.

    1993-09-01

    Thermal batteries are activated by the ignition of heat pellets. If the heat pellets are not sensitive enough to the ignition stimulus, the thermal battery will not activate, resulting in a dud. Thus, to assure reliable thermal batteries, it is important to demonstrate that the pellets have satisfactory ignition sensitivity by testing a number of specimens. There are a number of statistical methods for evaluating the sensitivity of a device to some stimulus. Generally, these methods are applicable to the situation in which a single test is destructive to the specimen being tested, independent of the outcome of the test. In the case of thermal battery heat pellets, however, tests that result in a nonresponse do not totally degrade the specimen. This peculiarity provides opportunities to efficiently evaluate the ignition sensitivity of heat pellets. In this paper, a simple strategy for evaluating heat pellet ignition sensitivity (including experimental design and data analysis) is described. The relatively good asymptotic and small-sample efficiencies of this strategy are demonstrated.

  12. Development and validation of a railgun hydrogen pellet injector model

    SciTech Connect

    King, T.L.; Zhang, J.; Kim, K.

    1995-12-31

    A railgun hydrogen pellet injector model is presented and its predictions are compared with the experimental data. High-speed hydrogenic ice injection is the dominant refueling method for magnetically confined plasmas used in controlled thermonuclear fusion research. As experimental devices approach the scale of power-producing fusion reactors, the fueling requirements become increasingly more difficult to meet since, due to the large size and the high electron densities and temperatures of the plasma, hypervelocity pellets of a substantial size will need to be injected into the plasma continuously and at high repetition rates. Advanced technologies, such as the railgun pellet injector, are being developed to address this demand. Despite the apparent potential of electromagnetic launchers to produce hypervelocity projectiles, physical effects that were neither anticipated nor well understood have made it difficult to realize this potential. Therefore, it is essential to understand not only the theory behind railgun operation, but the primary loss mechanisms, as well. Analytic tools have been used by many researchers to design and optimize railguns and analyze their performance. This has led to a greater understanding of railgun behavior and opened the door for further improvement. A railgun hydrogen pellet injector model has been developed. The model is based upon a pellet equation of motion that accounts for the dominant loss mechanisms, inertial and viscous drag. The model has been validated using railgun pellet injectors developed by the Fusion Technology Research Laboratory at the University of Illinois at Urbana-Champaign.

  13. Advanced turbine/CO{sub 2} pellet accelerator

    SciTech Connect

    Foster, C.A.; Fisher, P.W.

    1994-09-01

    An advanced turbine/CO{sub 2} pellet accelerator is being evaluated as a depaint technology at Oak Ridge National Laboratory. The program, sponsored by Warner Robins Air Logistics Center, Robins Air Force Base, Georgia, has developed a robot-compatible apparatus that efficiently accelerates pellets of dry ice with a high-speed rotating wheel. In comparison to the more conventional compressed air sandblast pellet accelerators, the turbine system can achieve higher pellet speeds, has precise speed control, and is more than ten times as efficient. A preliminary study of the apparatus as a depaint technology has been undertaken. Depaint rates of military epoxy/urethane paint systems on 2024 and 7075 aluminum panels as a function of pellet speed and throughput have been measured. In addition, methods of enhancing the strip rate by combining infra-red heat lamps with pellet blasting have also been studied. The design and operation of the apparatus will be discussed along with data obtained from the depaint studies. Applications include removal of epoxy-based points from aircraft and the cleaning of surfaces contaminated with toxic, hazardous, or radioactive substances. The lack of a secondary contaminated waste stream is of great benefit.

  14. Design of pellet surface grooves for fission gas plenum

    SciTech Connect

    Carter, T.J.; Jones, L.R.; Macici, N.; Miller, G.C.

    1986-01-01

    In the Canada deuterium uranium pressurized heavy water reactor, short (50-cm) Zircaloy-4 clad bundles are fueled on-power. Although internal void volume within the fuel rods is adequate for the present once-through natural uranium cycle, the authors have investigated methods for increasing the internal gas storage volume needed in high-power, high-burnup, experimental ceramic fuels. This present work sought to prove the methodology for design of gas storage volume within the fuel pellets - specifically the use of grooves pressed or machined into the relatively cool pellet/cladding interface. Preanalysis and design of pellet groove shape and volume was accomplished using the TRUMP heat transfer code. Postirradiation examination (PIE) was used to check the initial design and heat transfer assumptions. Fission gas release was found to be higher for the grooved pellet rods than for the comparison rods with hollow or unmodified pellets. This had been expected from the initial TRUMP thermal analyses. The ELESIM fuel modeling code was used to check in-reactor performance, but some modifications were necessary to accommodate the loss of heat transfer surface to the grooves. It was concluded that for plenum design purposes, circumferential pellet grooves could be adequately modeled by the codes TRUMP and ELESIM.

  15. Overview of Recent Developments in Pellet Injection for ITER

    SciTech Connect

    Combs, Stephen Kirk; Baylor, Larry R; Meitner, Steven J; Caughman, John B; Rasmussen, David A; Maruyama, So

    2012-01-01

    Pellet injection is the primary fueling technique planned for core fueling of ITER burning plasmas. Also, the injection of relatively small pellets to purposely trigger rapid small edge localized modes (ELMs) has been proposed as a possible solution to the heat flux damage from larger natural ELMs likely to be an issue on the ITER divertor surfaces. The ITER pellet injection system is designed to inject pellets into the plasma through both inner and outer wall guide tubes. The inner wall guide tubes will provide high throughput pellet fueling while the outerwall guide tubes will be used primarily to trigger ELMs at a high frequency (>15 Hz). The pellet fueling rate ofeach injector is to be up to 120 Pa-m3/s, which will require the formation of solid D-T at a volumetric rate of ~1500 mm3/s. Two injectors are to be provided for ITER at the startup with a provision for up to six injectorsduring the D-T phase. The required throughput of each injector is greater than that of any injector built to date, and a novel twin-screw continuous extrusion system is being developed to meet the challenging design parameters. Status of the development activities will be presented, highlighting recent progress.

  16. Arthroscopic Removal of Shotgun Pellet From Within the Medial Meniscus

    PubMed Central

    Lacy, Kyle; Cooke, Chris; Cooke, Pat; Tonnos, Frederick

    2016-01-01

    Arthroscopic techniques are effective for the removal of intra-articular bullet and metal fragments after gunshot wounds to the shoulder, hip, knee, and sacroiliac joints. Surgical removal of bullets retained within the synovial joints is indicated; lead is dissolved by synovial fluid over time, leading to proliferative synovitis, lead arthropathy, elevated serum lead levels, and lead toxicity. We present an arthroscopic technique for removal of a shotgun pellet retained within the medial meniscus. In this technique, diagnostic knee arthroscopy is initially performed, which allows for localization of the pellet within the medial meniscus. An up-biter is used to resect the inner rim of meniscus surrounding the pellet, and the pellet is removed with a grasper. This arthroscopic approach is advantageous because it allows for efficient visualization of the pellet within the meniscus, thorough visualization of all compartments of the knee, a reduction in blood loss, and a decrease in surgical morbidity to the surrounding cartilaginous, neurovascular, and soft-tissue structures. This technique may therefore be one option to address bullet fragments or shotgun pellets that are retained within the medial meniscus. PMID:27073774

  17. Novel Routes for Improving Biocontrol Activity of Bacillus Based Bioinoculants

    PubMed Central

    Wu, Liming; Wu, Hui-Jun; Qiao, Junqing; Gao, Xuewen; Borriss, Rainer

    2015-01-01

    Biocontrol (BC) formulations prepared from plant-growth-promoting bacteria are increasingly applied in sustainable agriculture. Especially inoculants prepared from endospore-forming Bacillus strains have been proven as efficient and environmental-friendly alternative to chemical pesticides due to their long shelf life, which is comparable with that of agrochemicals. However, these formulations of the first generation are sometimes hampered in their action and do not fulfill in each case the expectations of the appliers. In this review we use the well-known plant-associated Bacillus amyloliquefaciens type strain FZB42 as example for the successful application of different techniques offered today by comparative, evolutionary and functional genomics, site-directed mutagenesis and strain construction including marker removal, for paving the way for preparing a novel generation of BC agents. PMID:26696998

  18. Trichoderma harzianum might impact phosphorus transport by arbuscular mycorrhizal fungi.

    PubMed

    De Jaeger, Nathalie; de la Providencia, Ivan E; de Boulois, Hervé Dupré; Declerck, Stéphane

    2011-09-01

    Trichoderma sp. is a biocontrol agent active against plant pathogens via mechanisms such as mycoparasitism. Recently, it was demonstrated that Trichoderma harzianum was able to parasitize the mycelium of an arbuscular mycorrhizal (AM) fungus, thus affecting its viability. Here, we question whether this mycoparasitism may reduce the capacity of Glomus sp. to transport phosphorus ((33)P) to its host plant in an in vitro culture system. (33)P was measured in the plant and in the fungal mycelium in the presence/absence of T. harzianum. The viability and metabolic activity of the extraradical mycelium was measured via succinate dehydrogenase and alkaline phosphatase staining. Our study demonstrated an increased uptake of (33)P by the AM fungus in the presence of T. harzianum, possibly related to a stress reaction caused by mycoparasitism. In addition, the disruption of AM extraradical hyphae in the presence of T. harzianum affected the (33)P translocation within the AM fungal mycelium and consequently the transfer of (33)P to the host plant. The effects of T. harzianum on Glomus sp. may thus impact the growth and function of AM fungi and also indirectly plant performance by influencing the source-sink relationship between the two partners of the symbiosis.

  19. Simple, inexpensive media for mass production of three entomophthoralean fungi.

    PubMed

    Leite, Luis G; Alves, Sérgio B; Batista Filho, Antonio; Roberts, Donald W

    2005-03-01

    The entomophthoralean fungi Batkoa sp., Furia sp. and Neozygites floridana have been suggested for biocontrol of insect pests: the first two for control of spittlebug pests of pasture and sugarcane, and the third for mites of agricultural importance. To develop these agents as biopesticides and bioacaricides, it is important to have available culture media that maximize production at low cost. The research reported here evaluates, in different combinations and concentrations, the effect of four complex sources of nitrogen on production of mycelium or hyphal bodies in liquid media of all three species. Yeast extract allowed the highest production of Batkoa sp., with a concentration of 0.5% being the most suitable for vegetative (mycelial) growth. The combination of 0.33% each of yeast extract + beef extract + skim milk allowed the highest production of Furia sp. Mycelium. The combination of yeast extract + skim milk (0.5% of each) allowed the second highest production of Furia sp., and was the most suitable for mass production due to the lower cost. The combination of 1 %each of yeast extract + peptone + skim milk was the most suitable for production of N. floridana hyphal bodies.

  20. Arresting and supplying apparatus for increasing pellet impact drilling speed per run

    NASA Astrophysics Data System (ADS)

    Kovalyov, A. V.; Isaev, Ye D.; Veryevkin, A. V.; Gorbenko, V. M.; Ulyanova, O. S.

    2015-11-01

    The paper describes pellet impact drilling which might be used to increase the drilling rate and the penetration rate of hard and tough rock drilling. Pellet impact drilling implies rock destruction by metal pellets having high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are recirculated in the bottom of the bore hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The arresting and supplying apparatus is supposed to increase speed per run in pellet impact drilling, as it not only replenishes the pellets but also supplies and then picks up the pellets from the bottom hole. The paper presents the design of the pellet-supplying component which ensures a portion of pellets supply to the bottom hole.

  1. Biocontrol of fouling pests: Effect of diversity, identity and density of control agents.

    PubMed

    Atalah, Javier; Newcombe, Emma M; Zaiko, Anastasija

    2016-04-01

    Augmentative biocontrol, using native natural enemies, has been suggested as a promising tool to control marine biofouling pests on artificial structures. However, there are still important knowledge gaps to be addressed before biocontrol can be considered as a management tool. In a field experiment on floating marine structures we examined intra- and interspecific consumer interactions among biocontrol agents on different surface orientations. We tested the effect of identity, density and diversity of three invertebrates (the 11-arm seastar Coscinasterias muricata, the sea urchin Evechinus chloroticus and the gastropod Cook's turban Cookia sulcata) to reduce established biofouling and to prevent fouling growth on defouled surfaces. High densities of biocontrol agents were not more effective at fouling control (cover and biomass) than low densities. Nor did multi-species treatments function more effectively than mono-specific ones. However, biocontrol agent identity was important, with the 11-arm seastar and Cook's turban being the most effective at fouling reduction and prevention, respectively. Surface orientation had a strong effect on the effectiveness of control agents, with the best results obtained on vertical compared to diagonal and underside surfaces. This study confirmed the potential of biocontrol as a management tool for marine pest, indicating that identity is more important than richness and density of control agents. It also highlighted the limitations of this approach on diagonal and underside surfaces, where control agents have limited retention ability. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Biocontrol Activity of the Local Strain of Metschnikowia pulcherrima on Different Postharvest Pathogens.

    PubMed

    Türkel, Sezai; Korukluoğlu, Mihriban; Yavuz, Mümine

    2014-01-01

    The strains of the yeast Metschnikowia pulcherrima have strong biocontrol activity against various microorganisms. Biocontrol activity of M. pulcherrima largely depends on its iron immobilizing pigment pulcherrimin. Biocontrol activity of pulcherrimin producing strain, M. pulcherrima UMY15, isolated from local vineyards, was tested on different molds that cause food spoilage. M. pulcherrima UMY15 was a very effective biocontrol agent against Penicillium roqueforti, P. italicum, P. expansum, and Aspergillus oryzae in in-vitro plate tests. However, the inhibitory activity of M. pulcherrima UMY15 was less effective on Fusarium sp. and A. niger species in biocontrol assays. In addition, M. pulcherrima UMY15 strain completely inhibited the germination and mycelia growth of A. oryzae, A. parasiticus, and Fusarium sp. spores on artificial wounds of apples when they coinoculated with M. pulcherrima UMY15. Moreover, when coinoculated, M. pulcherrima UMY15 strain also inhibited the growth of P. roqueforti, P. italicum, P. expansum, A. oryzae, Fusarium sp., and Rhizopus sp. in grape juice, indicating that M. pulcherrima UMY15 can be used as a very effective biocontrol yeast against various species of postharvest pathogens, including Penicillium, Aspergillus, Fusarium, and Rhizopus.

  3. Biocontrol Activity of the Local Strain of Metschnikowia pulcherrima on Different Postharvest Pathogens

    PubMed Central

    Türkel, Sezai; Korukluoğlu, Mihriban; Yavuz, Mümine

    2014-01-01

    The strains of the yeast Metschnikowia pulcherrima have strong biocontrol activity against various microorganisms. Biocontrol activity of M. pulcherrima largely depends on its iron immobilizing pigment pulcherrimin. Biocontrol activity of pulcherrimin producing strain, M. pulcherrima UMY15, isolated from local vineyards, was tested on different molds that cause food spoilage. M. pulcherrima UMY15 was a very effective biocontrol agent against Penicillium roqueforti, P. italicum, P. expansum, and Aspergillus oryzae in in-vitro plate tests. However, the inhibitory activity of M. pulcherrima UMY15 was less effective on Fusarium sp. and A. niger species in biocontrol assays. In addition, M. pulcherrima UMY15 strain completely inhibited the germination and mycelia growth of A. oryzae, A. parasiticus, and Fusarium sp. spores on artificial wounds of apples when they coinoculated with M. pulcherrima UMY15. Moreover, when coinoculated, M. pulcherrima UMY15 strain also inhibited the growth of P. roqueforti, P. italicum, P. expansum, A. oryzae, Fusarium sp., and Rhizopus sp. in grape juice, indicating that M. pulcherrima UMY15 can be used as a very effective biocontrol yeast against various species of postharvest pathogens, including Penicillium, Aspergillus, Fusarium, and Rhizopus. PMID:24860671

  4. Testing phenanthrene distribution properties of virgin plastic pellets and plastic eroded pellets found on Lesvos island beaches (Greece).

    PubMed

    Karapanagioti, Hrissi K; Klontza, Irene

    2008-05-01

    Plastic pellets have been characterized as toxic pollutant carriers throughout the world oceans and coastal zones. However, their sorptive properties are not yet well understood. In the present study, virgin pellets and plastic eroded pellets (PEP) are used to elucidate their distribution characteristics through distribution kinetic studies. Distribution occurs through diffusion into the pellet for all materials (polyethylene, polyoxymethylene, and PEP) except polypropylene (PP). Although diffusion into the polymer happens with similar rates for both freshwater and saltwater external solutions, apparent diffusion is dependent on the solution salinity because it results in higher equilibrium distribution coefficients. Distribution coefficient into the PEP is higher and diffusion is slower than into the virgin materials. This is attributed to increased crystallinity of the PEP due to weathering. PP demonstrates diffusion rates that are increased by salinity and is apparently faster than into the other polymers suggesting a surface diffusion process.

  5. Development of a Tritium Extruder for ITER Pellet Injection

    SciTech Connect

    M.J. Gouge; P.W. Fisher

    1998-09-01

    As part of the International Thermonuclear Experimental Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabricated a pellet injection system to test the mechanical and thermal properties of extruded tritium. Hydrogenic pellets will be used in ITER to sustain the fusion power in the plasma core and may be crucial in reducing first-wall tritium inventories by a process of "isotopic fueling" in which tritium-rich pellets fuel the burning plasma core and deuterium gas fuels the edge. This repeating single-stage pneumatic pellet injector, called the Tritium-Proof-of-Principle Phase II (TPOP-II) Pellet Injector, has a piston-driven mechanical extruder and is designed to extrude and accelerate hydrogenic pellets sized for the ITER device. The TPOP-II program has the following development goals: evaluate the feasibility of extruding tritium and deuterium-tritium (D-T) mixtures for use in future pellet injection systems; determine the mechanical and thermal properties of tritium and D-T extrusions; integrate, test, and evaluate the extruder in a repeating, single-stage light gas gun that is sized for the ITER application (pellet diameter -7 to 8 mm); evaluate options for recycling propellant and extruder exhaust gas; and evaluate operability and reliability of ITER prototypical fueling systems in an environment of significant tritium inventory that requires secondary and room containment systems. In tests with deuterium feed at ORNL, up to 13 pellets per extrusion have been extruded at rates up to 1 Hz and accelerated to speeds of 1.0 to 1.1 km/s, using hydrogen propellant gas at a supply pressure of 65 bar. Initially, deuterium pellets 7.5 mm in diameter and 11 mm in length were produced-the largest cryogenic pellets produced by the fusion program to date. These pellets represent about a 10% density perturbation to ITER. Subsequently, the extruder nozzle was modified to produce pellets that are almost 7.5-mm right circular

  6. Plant Growth Promotion Activity of Keratinolytic Fungi Growing on a Recalcitrant Waste Known as "Hair Waste".

    PubMed

    Cavello, Ivana A; Crespo, Juan M; García, Sabrina S; Zapiola, José M; Luna, María F; Cavalitto, Sebastián F

    2015-01-01

    Purpureocillium lilacinum (Thom) Samsom is one of the most studied fungi in the control of plant parasitic nematodes. However, there is not specific information on its ability to inhibit some pathogenic bacteria, fungi, or yeast. This work reports the production of several antifungal hydrolytic enzymes by a strain of P. lilacinum when it is grown in a medium containing hair waste. The growth of several plant-pathogenic fungi, Alternaria alternata, Aspergillus niger, and Fusarium culmorum, was considerably affected by the presence of P. lilacinum's supernatant. Besides antifungal activity, P. lilacinum demonstrates the capability to produce indoleacetic acid and ammonia during time cultivation on hair waste medium. Plant growth-promoting activity by cell-free supernatant was evidenced through the increase of the percentage of tomato seed germination from 71 to 85% after 48 hours. A 21-day plant growth assay using tomato plants indicates that crude supernatant promotes the growth of the plants similar to a reference fertilizer (p > 0.05). These results suggest that both strain and the supernatant may have potential to be considered as a potent biocontrol agent with multiple plant growth-promoting properties. To our knowledge, this is the first report on the antifungal, IAA production and tomato growth enhancing compounds produced by P. lilacinum LPSC #876.

  7. Effect of certain entomopathogenic fungi on oxidative stress and mortality of Periplaneta americana.

    PubMed

    Chaurasia, Abhilasha; Lone, Yaqoob; Wani, Owais; Gupta, U S

    2016-02-01

    The present paper reports the effects of Metarhizium anisopliae, Isaria fumosoroseus and Hirsutella thompsonaii on Periplaneta americana. I. fumosoroseus and H. thompsonaii were cultured at 28±1°C on potato carrot agar and M. anisopliae was cultured at 28±1°C on potato dextrose agar for 14days. Conidial suspensions of fungi were given to cockroaches through different routes. M. anisopliae shows high virulence against adult cockroaches and mortality ranges from 38.65% to 78.36% after 48h. I. fumosoroseus and H. thompsonii show less virulence compared to M. anisopliae. We also investigated the effect of these three fungi on the activity of lactate dehydrogenase, lipid peroxidation and catalase in different tissues of the insect to gain an understanding of the different target site. The result suggested that the activity of lactate dehydrogenase, catalase and level of malondialdehyde varies in different organs and through different routes of exposure. Based on mortality percentages, all tested fungi had high potentials for biocontrol agents against P. americana. Our study reveals for the first time that I. fumosoroseus and H. thompsonaii fungal infections initiate oxidative stress in the midgut, fat body, whole body and hemolymph of cockroach thereby suggesting them to be the target organs for oxidative damage.

  8. Influence of pellet diameter and length on the quality of pellets and performance, nutrient utilisation and digestive tract development of broilers fed on wheat-based diets.

    PubMed

    Abdollahi, M R; Ravindran, V; Wester, T J; Ravindran, G; Thomas, D V

    2013-06-01

    1. The influence of pellet diameter and length on the quality of pellets and performance, nutrient utilisation and digestive tract development of broilers given wheat-based diets was examined from 10 to 42 d of age. The experimental design was a 2 × 2 factorial arrangement of treatments evaluating two pellet diameters (3 and 4.76 mm) and two pellet lengths (3 and 6 mm). From 0 to 9 d of age, all birds were offered a common starter diet pelleted with a 3-mm diameter die and 3-mm length. Broiler grower (d 10 to 21) and finisher (d 22 to 42) diets, based on wheat, were formulated and then subjected to the 4 different treatments. 2. In grower diets, increasing pellet diameter and pellet length reduced the gelatinised starch (GS) content of the diets. In finisher diets, GS content of 3-mm diameter pellets did not change with increasing pellet length but decreased in 4.76-mm diameter pellets. 3. In grower and finisher diets, increments in intact pellet weight, pellet durability index and pellet hardness with increasing pellet length were greater in 3-mm diameter pellets than those with 4.76-mm diameter. 4. Increasing pellet length from 3 to 6 mm increased apparent metabolisable energy values. Neither the interaction nor main effects were significant for the ileal digestibility of nitrogen and starch. 5. During the grower period (d 10 to 21), birds given pellets of 6-mm length had greater body-weight gain than those given 3-mm length pellets. Feeding 6-mm length pellets decreased feed per body-weight gain compared to 3-mm length pellets. During the finisher (d 22 to 42) and whole grow-out (d 10 to 42) periods, while different pellet lengths had no effect on feed per body-weight gain values at 3-mm pellet diameter, increasing the pellet length decreased feed per body-weight gain at 4.76-mm pellet diameter. 6. Increasing pellet diameter and pellet length reduced the relative length of duodenum. Birds given 3-mm diameter pellets had heavier proventriculus compared to

  9. Phylogenetic diversity of culturable endophytic fungi in Dongxiang wild rice (Oryza rufipogon Griff), detection of polyketide synthase gene and their antagonistic activity analysis.

    PubMed

    Wang, Ya; Gao, Bo Liang; Li, Xi Xi; Zhang, Zhi Bin; Yan, Ri Ming; Yang, Hui Lin; Zhu, Du

    2015-11-01

    The biodiversity of plant endophytic fungi is enormous, numerous competent endophytic fungi are capable of providing different forms of fitness benefits to host plants and also could produce a wide array of bioactive natural products, which make them a largely unexplored source of novel compounds with potential bioactivity. In this study, we provided a first insights into revealing the diversity of culturable endophytic fungi in Dongxiang wild rice (Oryza rufipogon Griff.) from China using rDNA-ITS phylogenetic analysis. Here, the potential of fungi in producing bioactive natural products was estimated based on the beta-ketosynthase detected in the polyketide synthase (PKS) gene cluster and on the bioassay of antagonistic activity against two rice phytopathogens Thanatephorus cucumeris and Xanthomonas oryzae. A total of 229 endophytic fungal strains were validated in 19 genera. Among the 24 representative strains, 13 strains displayedantagonistic activity against the phytopathogens. Furthermore, PKS genes were detected in 9 strains, indicating their potential for synthesising PKS compounds. Our study confirms the phylogenetic diversity of endophytic fungi in O. rufipogon G. and highlights that endophytic fungi are not only promising resources of biocontrol agents against phytopathogens of rice plants, but also of bioactive natural products and defensive secondary metabolites.

  10. Comparison of novel granulated pellet-containing tablets and traditional pellet-containing tablets by artificial neural networks.

    PubMed

    Huang, Ying; Yao, Qinghe; Zhu, Chune; Zhang, Xuan; Qin, Lingzhen; Wang, Qinruo; Pan, Xin; Wu, Chuanbin

    2015-01-01

    Novel granulated pellets technique was adopted to prepare granulated pellet-containing tablets (GPCT). GPCT and traditional pellet-containing tablets (PCT) were prepared according to 29 formulations devised by the Design Expert 7.0, with doxycycline hydrochloride as model drug, blends of Eudragit FS 30D and Eudragit L 30D-55 as coating materials, for the comparison study to confirm the superiority of GPCT during compaction. Eudragit FS 30D content, coating weight gain, tablet hardness and pellet size were chosen as influential factors to investigate the properties and drug release behavior of tablets. The correlation coefficients between the experimental values and the predicted values by artificial neural networks (ANNs) for PCT and GPCT were 0.9474 and 0.9843, respectively, indicating the excellent prediction of ANNs. The similarity factors (f2) for release profiles of GPCT and the corresponding original pellets were higher than those of PCT, suggesting that the excipient layer of granulated pellets absorbed the compressing force and protected the integrity of coating films during compaction.

  11. Fungi: Strongmen of the Underground.

    ERIC Educational Resources Information Center

    Morrell, Patricia D.; Morrell, Jeffrey J.

    1999-01-01

    Presents an activity that stresses the role of fungi and decomposers, highlights the rapidity by which they complete this process, and allows students to experiment with ways to control the rate of decomposition. (CCM)

  12. Fungi: Strongmen of the Underground.

    ERIC Educational Resources Information Center

    Morrell, Patricia D.; Morrell, Jeffrey J.

    1999-01-01

    Presents an activity that stresses the role of fungi and decomposers, highlights the rapidity by which they complete this process, and allows students to experiment with ways to control the rate of decomposition. (CCM)

  13. Mycoparasitism studies of Trichoderma species against three phytopathogenic fungi: evaluation of antagonism and hydrolytic enzyme production.

    PubMed

    Qualhato, Thiago Fernandes; Lopes, Fabyano Alvares Cardoso; Steindorff, Andrei Stecca; Brandão, Renata Silva; Jesuino, Rosália Santos Amorim; Ulhoa, Cirano José

    2013-09-01

    Trichoderma spp. are used for biocontrol of several plant pathogens. However, their efficient interaction with the host needs to be accompanied by production of secondary metabolites and cell wall-degrading enzymes. Three parameters were evaluated after interaction between four Trichoderma species and plant-pathogenic fungi: Fusarium solani, Rhizoctonia solani and Sclerotinia sclerotiorum. Trichoderma harzianum and T. asperellum were the most effective antagonists against the pathogens. Most of the Trichoderma species produced toxic volatile metabolites, having significant effects on growth and development of the plant pathogens. When these species were grown in liquid cultures with cell walls from these plant pathogens, they produced and secreted β-1,3-glucanase, NAGAse, chitinase, acid phosphatase, acid proteases and alginate lyase.

  14. Centromeres of filamentous fungi

    PubMed Central

    Smith, Kristina M.; Galazka, Jonathan M.; Phatale, Pallavi A.; Connolly, Lanelle R.; Freitag, Michael

    2012-01-01

    How centromeres are assembled and maintained remains one of the fundamental questions in cell biology. Over the past 20 years the idea of centromeres as precise genetic loci has been replaced by the realization that it is predominantly the protein complement that defines centromere localization and function. Thus, placement and maintenance of centromeres are excellent examples of epigenetic phenomena in the strict sense. In contrast, the highly derived “point centromeres” of the budding yeast Saccharomyces cerevisiae and its close relatives are counterexamples for this general principle of centromere maintenance. While we have learned much in the past decade, it remains unclear if mechanisms for epigenetic centromere placement and maintenance are shared amongst various groups of organisms. For that reason it seems prudent to examine species from many different phylogenetic groups with the aim to extract comparative information that will yield a more complete picture of cell division in all eukaryotes. This review addresses what has been learned by studying the centromeres of filamentous fungi, a large, heterogeneous group of organisms that includes important plant, animal and human pathogens, saprobes and symbionts that fulfill essential roles in the biosphere, as well as a growing number of taxa that have become indispensable for industrial use. PMID:22752455

  15. Method to Produce Durable Pellets at Lower Energy Consumption Using High Moisture Corn Stover and a Corn Starch Binder in a Flat Die Pellet Mill

    PubMed Central

    Tumuluru, Jaya Shankar; Conner, Craig C.; Hoover, Amber N.

    2016-01-01

    A major challenge in the production of pellets is the high cost associated with drying biomass from 30 to 10% (w.b.) moisture content. At Idaho National Laboratory, a high-moisture pelleting process was developed to reduce the drying cost. In this process the biomass pellets are produced at higher feedstock moisture contents than conventional methods, and the high moisture pellets produced are further dried in energy efficient dryers. This process helps to reduce the feedstock moisture content by about 5-10% during pelleting, which is mainly due to frictional heat developed in the die. The objective of this research was to explore how binder addition influences the pellet quality and energy consumption of the high-moisture pelleting process in a flat die pellet mill. In the present study, raw corn stover was pelleted at moistures of 33, 36, and 39% (w.b.) by addition of 0, 2, and 4% pure corn starch. The partially dried pellets produced were further dried in a laboratory oven at 70 °C for 3-4 hr to lower the pellet moisture to less than 9% (w.b.). The high moisture and dried pellets were evaluated for their physical properties, such as bulk density and durability. The results indicated that increasing the binder percentage to 4% improved pellet durability and reduced the specific energy consumption by 20-40% compared to pellets with no binder. At higher binder addition (4%), the reduction in feedstock moisture during pelleting was <4%, whereas the reduction was about 7-8% without the binder. With 4% binder and 33% (w.b.) feedstock moisture content, the bulk density and durability values observed of the dried pellets were >510 kg/m3 and >98%, respectively, and the percent fine particles generated was reduced to <3%. PMID:27340875

  16. Method to Produce Durable Pellets at Lower Energy Consumption Using High Moisture Corn Stover and a Corn Starch Binder in a Flat Die Pellet Mill.

    PubMed

    Tumuluru, Jaya Shankar; Conner, Craig C; Hoover, Amber N

    2016-06-15

    A major challenge in the production of pellets is the high cost associated with drying biomass from 30 to 10% (w.b.) moisture content. At Idaho National Laboratory, a high-moisture pelleting process was developed to reduce the drying cost. In this process the biomass pellets are produced at higher feedstock moisture contents than conventional methods, and the high moisture pellets produced are further dried in energy efficient dryers. This process helps to reduce the feedstock moisture content by about 5-10% during pelleting, which is mainly due to frictional heat developed in the die. The objective of this research was to explore how binder addition influences the pellet quality and energy consumption of the high-moisture pelleting process in a flat die pellet mill. In the present study, raw corn stover was pelleted at moistures of 33, 36, and 39% (w.b.) by addition of 0, 2, and 4% pure corn starch. The partially dried pellets produced were further dried in a laboratory oven at 70 °C for 3-4 hr to lower the pellet moisture to less than 9% (w.b.). The high moisture and dried pellets were evaluated for their physical properties, such as bulk density and durability. The results indicated that increasing the binder percentage to 4% improved pellet durability and reduced the specific energy consumption by 20-40% compared to pellets with no binder. At higher binder addition (4%), the reduction in feedstock moisture during pelleting was <4%, whereas the reduction was about 7-8% without the binder. With 4% binder and 33% (w.b.) feedstock moisture content, the bulk density and durability values observed of the dried pellets were >510 kg/m(3) and >98%, respectively, and the percent fine particles generated was reduced to <3%.

  17. Fungi contamination of drinking water.

    PubMed

    Al-Gabr, Hamid Mohammad; Zheng, Tianling; Yu, Xin

    2014-01-01

    Aquatic fungi commonly infest various aqueous environments and play potentially crucial roles in nutrient and carbon cycling. Aquatic fungi also interact with other organisms to influence food web dynamics. In recent decades, numerous studies have been conducted to address the problem of microorganism contamination of water. The major concern has been potential effects on human health from exposure to certain bacteria, viruses, and protozoa that inhabit water and the microbial metabolites,pigments, and odors which are produced in the water, and their effects on human health and animals. Fungi are potentially important contaminants because they produce certain toxic metabolites that can cause severe health hazards to humans and animals. Despite the potential hazard posed by fungi, relatively few studies on them as contaminants have been reported for some countries.A wide variety of fungi species have been isolated from drinking water, and some of them are known to be strongly allergenic and to cause skin irritation, or immunosuppression in immunocompromised individuals (e.g., AIDS, cancer, or organ transplant patients). Mycotoxins are naturally produced as secondary metabolites by some fungi species, and exposure of humans or animals to them can cause health problems. Such exposure is likely to occur from dietary intake of either food,water or beverages made with water. However, mycotoxins, as residues in water,may be aerosolized when showering or when being sprayed for various purposes and then be subject to inhalation. Mycotoxins, or at least some of them, are regarded to be carcinogenic. There is also some concern that toxic mycotoxins or other secondary metabolites of fungi could be used by terrorists as a biochemical weapon by adding amounts of them to drinking water or non drinking water. Therefore, actions to prevent mycotoxin contaminated water from affecting either humans or animals are important and are needed. Water treatment plants may serve to partially

  18. Methyl Halide Production by Fungi

    NASA Astrophysics Data System (ADS)

    Dailey, G. D.; Varner, R. K.; Blanchard, R. O.; Sive, B. C.; Crill, P. M.

    2005-12-01

    Methyl chloride (CH3Cl), methyl bromide (CH3Br) and methyl iodide (CH3I) are methyl halide gases that contribute significant amounts of halogen radicals to the atmosphere. In an effort to better understand the global budget of methyl halides and their impact on the atmosphere, we need to identify the natural sources in addition to the known anthropogenic sources of these compounds. We are investigating the role of fungi in the production of methyl halides in the soils and wetlands in southern New Hampshire, USA. Previous research has shown that wood decay fungi and ectomycorrhizal fungi, which are within a group of fungi called basidiomycetes, emit methyl halides. In our study, measurements of headspace gas extracted from flasks containing fungi grown in culture demonstrate that a variety of fungi, including basidiomycetes and non-basidiomycetes, emit methyl halides. Our research sites include four ecosystems: an agricultural field, a temperate forest, a fresh water wetland, and coastal salt marshes. We have collected and isolated fungi at each site by culturing tissue samples of fruiting bodies and plant material, by using wood baits, and from the direct culture of soil. We compared the rates of methyl halide emissions from the fungi in the four ecosystems. In addition, we measured emissions from previously assayed fungal isolates after reintroducing them to sterilized soils that were collected from their original environments. Fungal biomass was determined by substrate-induced respiration (SIR). The emission rate by the fungus was determined by a linear regression of the concentration of methyl halide in the sample headspace over time divided by the fungal biomass.

  19. Aliphatic hydrocarbons of the fungi.

    NASA Technical Reports Server (NTRS)

    Weete, J. D.

    1972-01-01

    Review of studies of aliphatic hydrocarbons which have been recently detected in the spores of phytopathogenic fungi, and are found to be structurally very similar to the alkanes of higher plants. It appears that the hydrocarbon components of the few mycelial and yeast forms reported resemble the distribution found in bacteria. The occurence and distribution of these compounds in the fungi is discussed. Suggested functional roles of fungal spore alkanes are presented.

  20. [Fungi, pets and their owners].

    PubMed

    Noël, F; Piérard-Franchimont, C; Piérard, G E; Quatresooz, P

    2011-11-01

    Some parasitic or pathogen fungi for pet skin are possibly transmitted to humans in whom they are responsible for superficial mycozoonoses. Cats, dogs and some small rodents are commonly involved. The lesions correspond to glabrous skin dermatophytoses and to microsporic tinea of the scalp. These disorders represent the vast majority of the prevalent mycozoonoses in Wallonia. Microsporum canis and Trichophyton mentagrophytes are the two fungi that are commonly involved.

  1. Aliphatic hydrocarbons of the fungi.

    NASA Technical Reports Server (NTRS)

    Weete, J. D.

    1972-01-01

    Review of studies of aliphatic hydrocarbons which have been recently detected in the spores of phytopathogenic fungi, and are found to be structurally very similar to the alkanes of higher plants. It appears that the hydrocarbon components of the few mycelial and yeast forms reported resemble the distribution found in bacteria. The occurence and distribution of these compounds in the fungi is discussed. Suggested functional roles of fungal spore alkanes are presented.

  2. Potential Role of Exoglucanase Genes (WaEXG1 and WaEXG2) in the Biocontrol Activity of Wickerhamomyces anomalus.

    PubMed

    Parafati, Lucia; Cirvilleri, Gabriella; Restuccia, Cristina; Wisniewski, Michael

    2016-11-05

    The use of yeasts, including Wickerhamomyces anomalus, as biocontrol agents of fungi responsible for postharvest diseases of fruits and vegetables has been investigated for the past two decades. Among a variety of mechanisms, the production of glucanases coded by the "killer genes" WaEXG1 and WaEXG2 have been reported to play a role in the ability of yeast to inhibit other fungi. The objective of the present study was to determine the expression of these genes by RT-qPCR, utilizing gene-specific primers, when W. anomalus was grown on grape berries and oranges that were either non-inoculated or inoculated with Botrytis cinerea or Penicillium digitatum, or in minimal media supplemented with cell walls of various plant pathogens and different amounts of glucose. Results indicated that WaEXG2 was more responsive than WaEXG1 to the nutritional environment (including the addition of glucose to cell wall-amended media) in vitro and appeared to play a greater role in the cellular metabolism of W. anomalus. WaEXG2 expression also appeared to be more responsive to the presence of cell walls of P. digitatum and B. cinerea than other fungal species, whereas the same level of induction was not seen in vivo when the yeast was grown in wounded/pathogen-inoculated fruits.

  3. Apparatus and method for classifying fuel pellets for nuclear reactor

    DOEpatents

    Wilks, Robert S.; Sternheim, Eliezer; Breakey, Gerald A.; Sturges, Jr., Robert H.; Taleff, Alexander; Castner, Raymond P.

    1984-01-01

    Control for the operation of a mechanical handling and gauging system for nuclear fuel pellets. The pellets are inspected for diameters, lengths, surface flaws and weights in successive stations. The control includes, a computer for commanding the operation of the system and its electronics and for storing and processing the complex data derived at the required high rate. In measuring the diameter, the computer enables the measurement of a calibration pellet, stores that calibration data and computes and stores diameter-correction factors and their addresses along a pellet. To each diameter measurement a correction factor is applied at the appropriate address. The computer commands verification that all critical parts of the system and control are set for inspection and that each pellet is positioned for inspection. During each cycle of inspection, the measurement operation proceeds normally irrespective of whether or not a pellet is present in each station. If a pellet is not positioned in a station, a measurement is recorded, but the recorded measurement indicates maloperation. In measuring diameter and length a light pattern including successive shadows of slices transverse for diameter or longitudinal for length are projected on a photodiode array. The light pattern is scanned electronically by a train of pulses. The pulses are counted during the scan of the lighted diodes. For evaluation of diameter the maximum diameter count and the number of slices for which the diameter exceeds a predetermined minimum is determined. For acceptance, the maximum must be less than a maximum level and the minimum must exceed a set number. For evaluation of length, the maximum length is determined. For acceptance, the length must be within maximum and minimum limits.

  4. Hot-melt extrusion of sugar-starch-pellets.

    PubMed

    Yeung, Chi-Wah; Rein, Hubert

    2015-09-30

    Sugar-starch-pellets (syn. sugar spheres) are usually manufactured through fluidized bed granulation or wet extrusion techniques. This paper introduces hot-melt extrusion (HME) as an alternative method to manufacture sugar-starch-pellets. A twin-screw extruder coupled with a Leistritz Micro Pelletizer (LMP) cutting machine was utilized for the extrusion of different types (normal-, waxy-, and high-amlyose) of corn starch, blended with varying amounts of sucrose. Pellets were characterized for their physicochemical properties including crystallinity, particle size distribution, tensile strength, and swelling expansion. Furthermore, the influence of sugar content and humidity on the product was investigated. Both sucrose and water lowered the Tg of the starch system allowing a convenient extrusion process. Mechanical strength and swelling behavior could be associated with varying amylose and amylopectin. X-ray powder diffractometric (XRPD) peaks of increasing sucrose contents appeared above 30%. This signified the oversaturation of the extruded starch matrix system with sucrose. Otherwise, had the dissolved sucrose been embedded into the molten starch matrix, no crystalline peak could have been recognized. The replacement of starch with sucrose reduced the starch pellets' swelling effect, which resulted in less sectional expansion (SEI) and changed the surface appearance. Further, a nearly equal tensile strength could be detected for sugar spheres with more than 40% sucrose. This observation stands in good relation with the analyzed values of the commercial pellets. Both techniques (fluidized bed and HME) allowed a high yield of spherical pellets (less friability) for further layering processes. Thermal influence on the sugar-starch system is still an obstacle to be controlled.

  5. Hydrophobins are required for conidial hydrophobicity and plant root colonization in the fungal biocontrol agent Clonostachys rosea

    PubMed Central

    2014-01-01

    Background Filamentous fungi produce small cysteine rich surface active amphiphilic hydrophobins on the outer surface of cell walls that mediate interactions between the fungus and the environment. The role of hydrophobins in surface hydrophobicity, sporulation, fruit body formation, recognition and adhesion to host surface and virulence have been reported. The aim of the present study was to characterize the biological function of hydrophobins in the fungal biocontrol agent Clonostachys rosea in order to understand their potential roles in biocontrol mechanisms. Results Based on the presence of hydrophobin domains, cysteine spacing patterns and hydropathy plots, we identified three class II hydrophobin genes in C. rosea. Gene expression analysis showed basal expression of Hyd1, Hyd2 and Hyd3 in all conditions tested with the exception of induced Hyd1 expression in conidiating mycelium. Interestingly, up-regulation of Hyd1, Hyd2 and Hyd3 was found during C. rosea self interaction compared to interactions with the fungal plant pathogens Botrytis cinerea or Fusarium graminearum in dual culture assays. Phenotypic analysis of C. rosea deletion and complementation strains showed that Hyd1 and Hyd3 are jointly required for conidial hydrophobicity, although no difference in mycelia hydrophobicity was found between wild type (WT) and mutant strains. Interestingly, mutant strains showed increased growth rates, conidiation and enhanced tolerances of conidia to abiotic stresses. Antagonism tests using in vitro dual culture and detached leaf assays showed that the mutant strains were more aggressive towards B. cinerea, F. graminearum or Rhizoctonia solani, and that aggression was partly related to earlier conidial germination and enhanced tolerance of mutant strains to secreted fungal metabolites. Furthermore, in vitro Arabidopsis thaliana root colonization assays revealed reduced root colonization ability of the ΔHyd3 strain, but not for the ΔHyd1 strain. Furthermore

  6. Fungi producing significant mycotoxins.

    PubMed

    2012-01-01

    Mycotoxins are secondary metabolites of microfungi that are known to cause sickness or death in humans or animals. Although many such toxic metabolites are known, it is generally agreed that only a few are significant in causing disease: aflatoxins, fumonisins, ochratoxin A, deoxynivalenol, zearalenone, and ergot alkaloids. These toxins are produced by just a few species from the common genera Aspergillus, Penicillium, Fusarium, and Claviceps. All Aspergillus and Penicillium species either are commensals, growing in crops without obvious signs of pathogenicity, or invade crops after harvest and produce toxins during drying and storage. In contrast, the important Fusarium and Claviceps species infect crops before harvest. The most important Aspergillus species, occurring in warmer climates, are A. flavus and A. parasiticus, which produce aflatoxins in maize, groundnuts, tree nuts, and, less frequently, other commodities. The main ochratoxin A producers, A. ochraceus and A. carbonarius, commonly occur in grapes, dried vine fruits, wine, and coffee. Penicillium verrucosum also produces ochratoxin A but occurs only in cool temperate climates, where it infects small grains. F. verticillioides is ubiquitous in maize, with an endophytic nature, and produces fumonisins, which are generally more prevalent when crops are under drought stress or suffer excessive insect damage. It has recently been shown that Aspergillus niger also produces fumonisins, and several commodities may be affected. F. graminearum, which is the major producer of deoxynivalenol and zearalenone, is pathogenic on maize, wheat, and barley and produces these toxins whenever it infects these grains before harvest. Also included is a short section on Claviceps purpurea, which produces sclerotia among the seeds in grasses, including wheat, barley, and triticale. The main thrust of the chapter contains information on the identification of these fungi and their morphological characteristics, as well as factors

  7. An In vitro Study of Bio-Control and Plant Growth Promotion Potential of Salicaceae Endophytes.

    PubMed

    Kandel, Shyam L; Firrincieli, Andrea; Joubert, Pierre M; Okubara, Patricia A; Leston, Natalie D; McGeorge, Kendra M; Mugnozza, Giuseppe S; Harfouche, Antoine; Kim, Soo-Hyung; Doty, Sharon L

    2017-01-01

    Microbial communities in the endosphere of Salicaceae plants, poplar (Populus trichocarpa) and willow (Salix sitchensis), have been demonstrated to be important for plant growth promotion, protection from biotic and abiotic stresses, and degradation of toxic compounds. Our study aimed to investigate bio-control activities of Salicaceae endophytes against various soil borne plant pathogens including Rhizoctonia solani AG-8, Fusarium culmorum, Gaeumannomyces graminis var. tritici, and Pythium ultimum. Additionally, different plant growth promoting traits such as biological nitrogen fixation (BNF), indole-3-acetic acid (IAA) biosynthesis, phosphate solubilization, and siderophore production were assessed in all bio-control positive strains. Burkholderia, Rahnella, Pseudomonas, and Curtobacterium were major endophyte genera that showed bio-control activities in the in-vitro assays. The bio-control activities of Burkholderia strains were stronger across all tested plant pathogens as compared to other stains. Genomes of sequenced Burkholderia strains WP40 and WP42 were surveyed to identify the putative genes involved in the bio-control activities. The ocf and hcnABC gene clusters responsible for biosynthesis of the anti-fungal metabolites, occidiofungin and hydrogen cyanide, are present in the genomes of WP40 and WP42. Nearly all endophyte strains showing the bio-control activities produced IAA, solubilized tricalcium phosphate, and synthesized siderophores in the culture medium. Moreover, some strains reduced acetylene into ethylene in the acetylene reduction assay, a common assay used for BNF. Salicaceae endophytes could be useful for bio-control of various plant pathogens, and plant growth promotion possibly through the mechanisms of BNF, IAA production, and nutrient acquisition.

  8. An In vitro Study of Bio-Control and Plant Growth Promotion Potential of Salicaceae Endophytes

    PubMed Central

    Kandel, Shyam L.; Firrincieli, Andrea; Joubert, Pierre M.; Okubara, Patricia A.; Leston, Natalie D.; McGeorge, Kendra M.; Mugnozza, Giuseppe S.; Harfouche, Antoine; Kim, Soo-Hyung; Doty, Sharon L.

    2017-01-01

    Microbial communities in the endosphere of Salicaceae plants, poplar (Populus trichocarpa) and willow (Salix sitchensis), have been demonstrated to be important for plant growth promotion, protection from biotic and abiotic stresses, and degradation of toxic compounds. Our study aimed to investigate bio-control activities of Salicaceae endophytes against various soil borne plant pathogens including Rhizoctonia solani AG-8, Fusarium culmorum, Gaeumannomyces graminis var. tritici, and Pythium ultimum. Additionally, different plant growth promoting traits such as biological nitrogen fixation (BNF), indole-3-acetic acid (IAA) biosynthesis, phosphate solubilization, and siderophore production were assessed in all bio-control positive strains. Burkholderia, Rahnella, Pseudomonas, and Curtobacterium were major endophyte genera that showed bio-control activities in the in-vitro assays. The bio-control activities of Burkholderia strains were stronger across all tested plant pathogens as compared to other stains. Genomes of sequenced Burkholderia strains WP40 and WP42 were surveyed to identify the putative genes involved in the bio-control activities. The ocf and hcnABC gene clusters responsible for biosynthesis of the anti-fungal metabolites, occidiofungin and hydrogen cyanide, are present in the genomes of WP40 and WP42. Nearly all endophyte strains showing the bio-control activities produced IAA, solubilized tricalcium phosphate, and synthesized siderophores in the culture medium. Moreover, some strains reduced acetylene into ethylene in the acetylene reduction assay, a common assay used for BNF. Salicaceae endophytes could be useful for bio-control of various plant pathogens, and plant growth promotion possibly through the mechanisms of BNF, IAA production, and nutrient acquisition. PMID:28348550

  9. Biocontrol of verticillium wilt and colonization of cotton plants by an endophytic bacterial isolate.

    PubMed

    Li, C-H; Shi, L; Han, Q; Hu, H-L; Zhao, M-W; Tang, C-M; Li, S-P

    2012-09-01

    To explore biocontrol potential of 39 DAEB isolates (doubly antagonistic towards both Verticillium dahliae Kleb and Fusarium oxysporum) against verticillium wilt of cotton and to elucidate colonization and category characteristics of an endophytic bacterium with significant biocontrol activity. Thirty-nine antagonistic endophytic bacteria strains were tested for their ability to control verticillium wilt in cotton plants caused by a defoliating pathotype of V. dahliae 107 in cotton under controlled conditions. The biocontrol trial revealed that an endophytic bacterium, designated HA02, showed a significant biocontrol activity to V. dahliae 107. After cotton seedlings were inoculated with a gfp gene-tagged HA02 (HA02-gfp), HA02-gfp populations were higher in the root than in the stem; in addition, the HA02-gfp was distributed in the maturation zone of cotton root. Furthermore, HA02-gfp also colonized seedlings of maize, rape and soybean after the bacteria inoculation. Phylogenetic trees based on 16S rDNA sequences combined with morphological, physiological and identification showed that the bacterium belongs to the Enterobacter genus. Our results showed that only 1 of 39 DAEB isolates demonstrated more efficient biocontrol potential towards V. dahliae 107 in greenhouse and field trials. HA02-gfp mainly colonized cotton in roots. In addition, we quantitatively observed HA02 colonization in other hosts. HA02 belongs to the Enterobacter genus. This is the first study on biocontrol to defoliating pathotype of V. dahliae Kleb by endophytic bacteria. The HA02 showed effective biocontrol to V. dahliae 107 in greenhouse and field trials. Furthermore, we assessed the quantitative and qualitative colonization of HA02 in cotton seedlings. Our study provides basic information to further explore managing strategies to control this critical disease. © 2012 The Authors Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

  10. Indirect effects of biocontrol of an invasive riparian plant (Tamarix) alters habitat and reduces herpetofauna abundance

    USGS Publications Warehouse

    Bateman, H.L.; Merritt, D.M.; Glenn, E.P.; Nagler, P.L.

    2014-01-01

    The biological control agent (tamarisk leaf beetle, Diorhabda spp.) is actively being used to defoliate exotic saltcedar or tamarisk (Tamarix spp.) in riparian ecosystems in western USA. The Virgin River in Arizona and Nevada is a system where tamarisk leaf beetle populations are spreading. Saltcedar biocontrol, like other control methods, has the potential to affect non-target species. Because amphibians and reptiles respond to vegetation changes in habitat and forage in areas where beetles are active, herpetofauna are model taxa to investigate potential impacts of biocontrol defoliation. Our objectives related herpetofauna abundance to vegetation cover and indices (normalized difference vegetation index, NDVI; enhanced vegetation index, EVI) and timing of biocontrol defoliation. We captured herpetofauna and ground-dwelling arthropods in trap arrays and measured vegetation using remotely sensed images and on-the-ground measurements at 16–21 sites 2 years before (2009–2010) and 2 years following (2011–2012) biocontrol defoliation. Following defoliation, riparian stands (including stands mixed with native and exotic trees and stands of monotypic exotic saltcedar) had significantly lower NDVI and EVI values and fewer captures of marked lizards. Total captures of herpetofauna (toads, lizards, and snakes) were related to higher vegetation cover and sites with a lower proportion of saltcedar. Our results suggest that effects of biocontrol defoliation are likely to be site-specific and depend upon the proportion of native riparian trees established prior to biocontrol introduction and defoliation. The mechanisms by which habitat structure, microclimate, and ultimately vertebrate species are affected by exotic plant biocontrol riparian areas should be a focus of natural-resource managers.

  11. Production of trichodiene by Trichoderma harzianum alters the perception of this biocontrol strain by plants and antagonized fungi

    USDA-ARS?s Scientific Manuscript database

    Trichothecenes are phytotoxic sesquiterpenoid compounds of fungal origin which can act as virulence factors in plant diseases. Harzianum A (HA) is a non-phytotoxic trichothecene produced by Trichoderma arundinaceum. The first step in the biosynthesis of HA is the conversion of farnesyl diphosphate t...

  12. Fungi with multifunctional lifestyles: endophytic insect pathogenic fungi.

    PubMed

    Barelli, Larissa; Moonjely, Soumya; Behie, Scott W; Bidochka, Michael J

    2016-04-01

    This review examines the symbiotic, evolutionary, proteomic and genetic basis for a group of fungi that occupy a specialized niche as insect pathogens as well as endophytes. We focus primarily on species in the genera Metarhizium and Beauveria, traditionally recognized as insect pathogenic fungi but are also found as plant symbionts. Phylogenetic evidence suggests that these fungi are more closely related to grass endophytes and diverged from that lineage ca. 100 MYA. We explore how the dual life cycles of these fungi as insect pathogens and endophytes are coupled. We discuss the evolution of insect pathogenesis while maintaining an endophytic lifestyle and provide examples of genes that may be involved in the transition toward insect pathogenicity. That is, some genes for insect pathogenesis may have been co-opted from genes involved in endophytic colonization. Other genes may be multifunctional and serve in both lifestyle capacities. We suggest that their evolution as insect pathogens allowed them to effectively barter a specialized nitrogen source (i.e. insects) with host plants for photosynthate. These ubiquitous fungi may play an important role as plant growth promoters and have a potential reservoir of secondary metabolites.

  13. Particle transport in pellet fueled JET (Jet European Torus) plasmas

    SciTech Connect

    Baylor, L.R.

    1990-01-01

    Pellet fueling experiments have been carried out on the Joint European Torus (JET) tokamak with a multi-pellet injector. The pellets are injected at speeds approaching 1400 m/s and penetrate deep into the JET plasma. Highly peaked electron density profiles are achieved when penetration of the pellets approaches or goes beyond the magnetic axis, and these peaked profiles persist for more than two seconds in ohmic discharges and over one second in ICRF heated discharges. In this dissertation, analysis of electron particle transport in multi-pellet fueled JET limiter plasmas under a variety of heating conditions is described. The analysis is carried out with a one and one-half dimensional radial particle transport code to model the experimental density evolution with various particle transport coefficients. These analyses are carried out in plasmas with ohmic heating, ICRF heating, and neural beam heating, in limiter configurations. Peaked density profile cases are generally characterized by diffusion coefficients with a central (r/a < 0.5) diffusivity {approximately}0.1 m{sup 2}/s that increases rapidly to {approximately}0.3 m{sup 2}/s at r/a = 0.6 and then increases out to the plasma edge as (r/a){sup 2}. These discharges can be satisfactorily modeled without any anomalous convective (pinch) flux. 79 refs., 60 figs.

  14. Statistical analysis of deer and elk pellet-group data

    SciTech Connect

    White, G.C.; Eberhardt, L.E.

    1980-01-01

    Several authors have demonstrated empirically the fit of observed pellet-group data from mule deer, white-tailed deer, and elk to the negative binomial distribution. This distribution is described by 2 parameters: the mean, m, and the positive exponent, k. The parameter k is a measure of contagion. As over-dispersion increases, k ..-->.. 0; conversely, as the pellet groups approach a random distribution, k ..-->.. infinity. Past application of the negative binomial distribution to pellet-group data required a common value for the parameter k in order to test for differences in mean number of pellet groups for different populations. We developed a method of testing for differences in the means of pellet-group data for 2 or more populations that does not require a common k value. Interval and point estimators of k and m were obtained by the method of maximum likelihood for a series of models where either m or k can be assumed constant for all populations. A set of FORTRAN subroutines is available to analyze negative binomial data.

  15. Modifying ability of titanium-based pelleted master alloys

    NASA Astrophysics Data System (ADS)

    Bazhin, V. Yu.; Savchenkov, S. A.; Kosov, Ya. I.

    2017-05-01

    The problem of enhancing the quality of pressed titanium master alloys is discussed to increase the rate and degree of dissolution of their components and to ensure the formation of a fine-grained structure in aluminum alloys. A technology of producing a pelleted titanium master alloy for effective correction of the chemical composition of an aluminum alloy in casting is developed and tested. Incoming inspection of the component composition and the flux distribution in the volume of pressed pellets of various manufacturers is performed. The rate of dissolution of pressed powder master alloys in the aluminum melt is studied, and their modifying ability is estimated after studying the microstructures of cast blanks. Molasses is used as a binder in a pelleted master alloy. As a result, we achieved a uniform flux distribution over the pellet volume and the formation of uniform pores after annealing as compared pelleted master alloys of other manufacturers. The fabricated alloying briquettes have higher strength characteristics and their dissolution rate in the aluminum melt is higher than those of analogs by 15-20%.

  16. Mechanisms controlling theophylline release from ethanol-resistant coated pellets.

    PubMed

    Rosiaux, Y; Velghe, C; Muschert, S; Chokshi, R; Leclercq, B; Siepmann, F; Siepmann, J

    2014-03-01

    To elucidate the mass transport mechanisms controlling drug release from recently proposed, ethanol-resistant, polymeric film coatings. Theophylline matrix pellets were coated with ethylcellulose: guar gum blends. Drug release from single pellets and ensembles of pellets was measured in various release media. Changes in the systems' morphology, composition and mechanical properties were monitored using SEM, gravimetrical analysis and a texture analyzer. Based on the obtained experimental results a mechanistically realistic mathematical model was identified and used to quantitatively predict drug release from coated pellets in ethanol-free and ethanol-containing bulk fluids. Drug diffusion though the intact polymeric film coatings is likely to be the dominant mass transport mechanism in the investigated systems, irrespective of the ethanol content in the surrounding environment. An appropriate solution of Fick's law could be used to quantitatively predict theophylline release from pellets coated with different ethylcellulose:guar gum blends at different coating levels. Importantly, independent experiments confirmed the theoretical predictions. In silico simulations can help facilitating the optimization of the novel ethanol-resistant polymeric film coatings, avoiding time-consuming and cost-intensive series of trial-and-error experiments. The presence/absence of ethanol does not affect the underlying drug release mechanisms.

  17. Nuclear fuel pellet sintering boat unloading apparatus and method

    SciTech Connect

    Huggins, T.B.; Widener, W.H.; Klapper, K.K.

    1990-05-22

    This patent describes a method for unloading nuclear fuel pellets from a sintering boat having an open top. It comprises: pivoting a transfer housing loaded with the boat filled with nuclear fuel pellets about a generally horizontal axis from an upright position remote from a pellet deposit surface to an inverted position adjacent to the deposit surface to move the boat from an upright to inverted orientation with the pellets retained within the boat by a latched lid in a closed condition on the housing; unlatching the lid of the housing as the housing reaches its inverted position but engaging the unlatched lid with the deposit surface to retain it in its closed condition; and reverse pivoting the housing from its inverted position back toward its upright position to permit the unlatched lid to pivot from the closed condition to an opened condition thereby allowing pellets to slide out of the open top of the inverted boat and down the opened lid of the housing to the deposit site.

  18. Unexpectedly high mercury level in pelleted commercial fish feed

    SciTech Connect

    Choi, M.H.; Cech, J.J. Jr.

    1998-10-01

    An unexpectedly high mercury (Hg) level was found in a pelleted commercial fish feed used to feed fish in laboratory and fish farm settings. Mean total Hg (T-Hg) concentration in the commercial fish pellets was 66 ppb. Mean total selenium (T-Se) concentration in the pellets was 1,120 ppb (ranging from 790 to 1,360 ppb). Total Hg and Se in the whole blood of Sacramento blackfish and in the fish feed were determined by inductively coupled plasma-mass spectrometry (ICP-MS). During a 10-week sampling period T-Hg in blood fluctuated between 35 and 56 ppb. A highly significant, positive correlation was found between T-Hg in the fish blood and in the fish feed through the sampling period. On the other hand, no correlation was found between T-Se in the fish feed and T-Hg or T-Se blood level. Researchers working with fish in Hg studies need to know that fish pellets may contain Hg and to consider the influence of these pellets in their results.

  19. Fertilizing value of broiler litter: effects of drying and pelletizing.

    PubMed

    López-Mosquera, M E; Cabaleiro, F; Sainz, M J; López-Fabal, A; Carral, E

    2008-09-01

    The effects of drying and pelletizing on the properties of broiler chicken litter, obtained from a farm in northwest Spain, were investigated. The drying and pelletizing process reduced among-batch variability in dry matter content, electrical conductivity, urea N, and K, S, Na, Fe, Cu and Cd contents, but increased among-batch variability in total N, ammonium N, nitrate N, total P and pH. N form contents in the pelletized product could be estimated with reasonable accuracy on the basis of dry matter content. Cr, Cu and Cd contents were all significantly lower in the dried pelletized product than in fresh litter, whereas Pb content was significantly higher. The dried pelletized product is of course clearly preferable to the fresh product as regards storage and handling, however, our results suggest a need to optimize the production process with the aim of reducing possible contamination during manufacture, and of minimizing variability in N form contents, P content and pH.

  20. Gyrokinetic simulations of particle transport in pellet fuelled JET discharges

    NASA Astrophysics Data System (ADS)

    Tegnered, D.; Oberparleiter, M.; Nordman, H.; Strand, P.; Garzotti, L.; Lupelli, I.; Roach, C. M.; Romanelli, M.; Valovič, M.; Contributors, JET

    2017-10-01

    Pellet injection is a likely fuelling method of reactor grade plasmas. When the pellet ablates, it will transiently perturb the density and temperature profiles of the plasma. This will in turn change dimensionless parameters such as a/{L}n,a/{L}T and plasma β. The microstability properties of the plasma then changes which influences the transport of heat and particles. In this paper, gyrokinetic simulations of a JET L-mode pellet fuelled discharge are performed. The ion temperature gradient/trapped electron mode turbulence is compared at the time point when the effect from the pellet is the most pronounced with a hollow density profile and when the profiles have relaxed again. Linear and nonlinear simulations are performed using the gyrokinetic code GENE including electromagnetic effects and collisions in a realistic geometry in local mode. Furthermore, global nonlinear simulations are performed in order to assess any nonlocal effects. It is found that the positive density gradient has a stabilizing effect that is partly counteracted by the increased temperature gradient in the this region. The effective diffusion coefficients are reduced in the positive density region region compared to the intra pellet time point. No major effect on the turbulent transport due to nonlocal effects are observed.

  1. Effects of thermal treatment on energy density and hardness of torrefied wood pellets

    SciTech Connect

    Peng, Jianghong; Wang, Jingsong; Bi, Xiaotao T.; Lim, C. Jim; Sokhansanj, Shahab; Peng, Hanchao; Jia, Dening

    2014-09-27

    Here, three types of wood pellets samples, including two types of commercial pellets and one type of lab-made control pellets were torrefied in a fixed bed unit to study the effect of thermal pretreatment on the quality of wood pellets. The quality of wood pellets was mainly characterized by the pellet density, bulk density, higher heating value, Meyer hardness, saturated moisture uptake, volumetric energy density, and energy yield. Results showed that torrefaction significantly decreased the pellet density, hardness, volumetric energy density, and energy yield. The higher heating value increased and the saturated moisture content decreased after torrefaction. In view of the lower density, lower hardness, lower volumetric energy density, and energy yield of torrefied pellets, it is recommended that biomass should be torrefied and then compressed to make strong pellets of high hydrophobicity and volumetric energy density.

  2. Effects of thermal treatment on energy density and hardness of torrefied wood pellets

    DOE PAGES

    Peng, Jianghong; Wang, Jingsong; Bi, Xiaotao T.; ...

    2014-09-27

    Here, three types of wood pellets samples, including two types of commercial pellets and one type of lab-made control pellets were torrefied in a fixed bed unit to study the effect of thermal pretreatment on the quality of wood pellets. The quality of wood pellets was mainly characterized by the pellet density, bulk density, higher heating value, Meyer hardness, saturated moisture uptake, volumetric energy density, and energy yield. Results showed that torrefaction significantly decreased the pellet density, hardness, volumetric energy density, and energy yield. The higher heating value increased and the saturated moisture content decreased after torrefaction. In view ofmore » the lower density, lower hardness, lower volumetric energy density, and energy yield of torrefied pellets, it is recommended that biomass should be torrefied and then compressed to make strong pellets of high hydrophobicity and volumetric energy density.« less

  3. Osteogenesis mechanism of chitosan-coated calcium sulfate pellets on the restoration of segmental bone defects.

    PubMed

    Cui, Xu; Zhao, Dewei; Zhang, Boxun; Gao, Yongliang

    2009-09-01

    A radial segmental defect model of a rabbit was used to study the restoration effect on defects treated with chitosan-coated pressed calcium sulfate pellets combined with recombinant human bone morphogenetic protein-2 (rhBMP-2), coated pressed calcium sulfate pellets, and uncoated pressed calcium sulfate pellets. Nothing was implanted in the control group. After 4, 8, and 12 weeks, the results indicated that coated pressed calcium sulfate pellets combined with rhBMP-2 and coated pressed calcium sulfate pellets facilitated new bone formation on defected bones and that, particularly, the coated pressed calcium sulfate pellets combined with rhBMP-2 was more effective than the coated pressed calcium sulfate pellet. Histologic and tetracycline fluorimetric findings showed that the osteogenesis mechanism of chitosan-coated pressed calcium sulfate pellets is membrane bone formation, and the pellets showed slightly slower resorption that closely coincides with the growth rate of new bone.

  4. Conjunctively screening of biocontrol agents (BCAs) against fusarium root rot and fusarium head blight caused by Fusarium graminearum.

    PubMed

    Wang, Lu-Yao; Xie, Yue-Shen; Cui, Yuan-Yu; Xu, Jianjun; He, Wei; Chen, Huai-Gu; Guo, Jian-Hua

    2015-08-01

    Fusarium root-rot and fusarium head blight are plant diseases caused by Fusarium sp. in different growth periods of wheat, bring heavy losses to crop production in China. This research is aiming to screen biocontrol agents conjunctively for controlling these two diseases at the same time, as well as evaluate our previous BCAs (Biological Control Agents) screening strategies in more complex situation, considering biocontrol is well concerned as an environmental-friendly plant disease controlling method. Totally 966 bacterial isolates were screened from different parts of wheat tissues, of which potential biocontrol values were detected according to their abilities in antagonism inhibition and secreting extracellular hydrolytic enzyme. Biocontrol tests against fusarium root rot and fusarium head blight were carried out on 37 bacterial isolates with potential biocontrol capacity after pre-selection through ARDRA- and BOX-PCR analysis on strains with high assessment points. We acquired 10 BCAs with obvious biocontrol efficacy (more than 40%) in greenhouse and field tests. Pseudomonas fluorescens LY1-8 performed well in both two tests (biocontrol efficacy: 44.62% and 58.31%), respectively. Overall, correlation coefficient is 0.720 between assessment values of 37 tested BCA strains and their biocontrol efficacy in trails against fusarium root rot; correlation coefficient is 0.806 between their assessment values and biocontrol efficacy in trails against fusarium head blight. We acquired 10 well-performed potential BCAs, especially P. fluorescens LY1-8 displayed good biocontrol capacity against two different diseases on wheat. Biocontrol efficacies results in both greenhouse and field tests showed high positive correlation with assessment values (0.720 and 0.806), suggesting that the BCAs screening and assessing strategy previously developed in our lab is also adaptable for conjunctively screening BCAs for controlling both root and shoot diseases on wheat caused by same

  5. Drug release, preclinical and clinical pharmacokinetics relationships of alginate pellets prepared by melt technology.

    PubMed

    Bose, Anirbandeep; Harjoh, Nurulaini; Pal, Tapan Kumar; Dan, Shubhasis; Wong, Tin Wui

    2016-01-01

    Alginate pellets prepared by the aqueous agglomeration technique experience fast drug dissolution due to the porous pre-formed calcium alginate microstructure. This study investigated in vitro drug release, preclinical and clinical pharmacokinetics relationships of intestinal-specific calcium acetate-alginate pellets against calcium-free and calcium carbonate-alginate pellets. Alginate pellets were prepared by solvent-free melt pelletization instead of aqueous agglomeration technique using chlorpheniramine maleate as model drug. A fast in situ calcium acetate dissolution in pellets resulted in rapid pellet breakup, soluble Ca(2+) crosslinking of alginate fragments and drug dissolution retardation at pH 1.2, which were not found in other pellet types. The preclinical drug absorption rate was lower with calcium acetate loaded than calcium-free alginate pellets. In human subjects, however, the extent and the rate of drug absorption were higher from calcium acetate-loaded pellets than calcium-free alginate pellets. The fine, dispersible and weakly gastric mucoadhesive calcium alginate pellets underwent fast human gastrointestinal transit. They released the drug at a greater rate than calcium-free pellets in the intestine, thereby promoting drug bioavailability. Calcium acetate was required as a disintegrant more than as a crosslinking agent clinically to promote pellet fragmentation, fast gastrointestinal transit and drug release in intestinal medium, and intestinal-specific drug bioavailability.

  6. Characterization of iron ore pellets with dextrin added organic binders under different time and temperature conditions

    NASA Astrophysics Data System (ADS)

    babu kotta, Anand; karak, Swapan kumar; Kumar, M.

    2017-02-01

    In the present work, Dextrin is used as a binder for iron ore pelletization, as it’s free from Silica and Alumina. Green pellets were prepared by mixing of iron ore particles (-75 μm) with varying binder percentage (1 wt. % bentonite, 0.5 and 1 wt. % of dextrin) separately. The green pellets were first dried in air for 24 h and then in an electric oven at 383 K for 4 h. The dried pellets were fired at varying temperatures (1173, 1273, 1373, and 1473 K) and indurated for 1 and 2 h. The samples were characterized for physical (pellet size) and mechanical (compressive strengths, porosity and hardness) properties. Good quality pellets were prepared with organic binder, and which increases the compressive strength of dry and fired pellets. Strength results are matching with the bentonite binder pellets and it is well above the industrially acceptable limit (250 kg/pellet). Porosity of the fired pellets decreases with increasing temperature and induration time. The hardness of the pellet varies from surface to core of the pellet. Moreover, the influence of wear mechanism (based on collisions) on pellets and its characteristics of generated particle size distribution (PSD) have been investigated. It was noticed that the material loss during wear test decreases with increasing strength of the pellet. From PSD analysis, the coarse particles were revealed that the collisions are dominating during wear.

  7. A feasibility study on pellet coating using a high-speed quasi-continuous coater.

    PubMed

    Cahyadi, Christine; Koh, Jackson Jie Sheng; Loh, Zhi Hui; Chan, Lai Wah; Heng, Paul Wan Sia

    2012-12-01

    Pellet coating is traditionally carried out using the Wurster coater. This study investigated the feasibility of pellet coating in a newly developed coater built with a unique airflow system, the Supercell™ coater (GEA Pharma Systems, UK). A full factorial design study was carried out to evaluate the influences of the spray rate of the coating dispersion, batch size of the pellet load, pellet size fraction and plenum pressure of the fluidizing air on the color coating of pellets in the Supercell™ coater. Results showed that pellets could be successfully coated using the Supercell™ coater. Higher plenum pressures and lower spray rates were found to minimize pellet agglomeration during coating. Although coating efficiencies were comparable amongst the different pellet size fractions, larger batch sizes of pellets were coated with higher efficiencies. Process optimization was carried out for each pellet size fraction and a large batch size (120 g) in combination with a high plenum pressure (1,500 mm WC) were deemed optimal. Optimal spray rates differed according to pellet size fraction and a lower spray rate was required for smaller pellets. Pellet flow patterns observed during coating were dependent on the pressure drop across the fluidized load. A 'swirling' pellet flow pattern was generally observed at coating conditions which led to optimal outcomes.

  8. Biocontrol of larval mosquitoes by Acilius sulcatus (Coleoptera: Dytiscidae)

    PubMed Central

    Chandra, Goutam; Mandal, Samir K; Ghosh, Arup K; Das, Dipanwita; Banerjee, Siddhartha S; Chakraborty, Sumanta

    2008-01-01

    Background Problems associated with resistant mosquitoes and the effects on non-target species by chemicals, evoke a reason to find alternative methods to control mosquitoes, like the use of natural predators. In this regard, aquatic coleopterans have been explored less compared to other insect predators. In the present study, an evaluation of the role of the larvae of Acilius sulcatus Linnaeus 1758 (Coleoptera: Dytiscidae) as predator of mosquito immatures was made in the laboratory. Its efficacy under field condition was also determined to emphasize its potential as bio-control agent of mosquitoes. Methods In the laboratory, the predation potential of the larvae of A. sulcatus was assessed using the larvae of Culex quinquefasciatus Say 1823 (Diptera: Culicidae) as prey at varying predator and prey densities and available space. Under field conditions, the effectiveness of the larvae of A. sulcatus was evaluated through augmentative release in ten cemented tanks hosting immatures of different mosquito species at varying density. The dip density changes in the mosquito immatures were used as indicator for the effectiveness of A. sulcatus larvae. Results A single larva of A. sulcatus consumed on an average 34 IV instar larvae of Cx. quinquefasciatus in a 24 h period. It was observed that feeding rate of A. sulcatus did not differ between the light-on (6 a.m. – 6 p.m.), and dark (6 p.m. – 6 a.m.) phases, but decreased with the volume of water i.e., space availability. The prey consumption of the larvae of A. sulcatus differed significantly (P < 0.05) with different prey, predator and volume combinations, revealed through univariate ANOVA. The field study revealed a significant decrease (p < 0.05) in larval density of different species of mosquitoes after 30 days from the introduction of A. sulcatus larvae, while with the withdrawal, a significant increase (p < 0.05) in larval density was noted indicating the efficacy of A. sulcatus in regulating mosquito

  9. Blood concentrations of chlortetracycline in macaws fed medicated pelleted feed.

    PubMed

    Flammer, K; Cassidy, D R; Landgraf, W W; Ross, P F

    1989-01-01

    A trial was conducted to determine the suitability of using a pelleted diet containing chlortetracycline (CTC) for treatment of chlamydiosis in macaws. Macaws, normally fed seed and fruit diets in captivity, are notoriously difficult to treat with CTC-medicated mash diets. Healthy macaws fed a pelleted diet containing 1% or 1.5% CTC for 30 or 45 days maintained adequate food intake and mean blood concentrations of 1-2 CTC micrograms/ml blood throughout the treatment period. There were no significant differences between blood concentrations induced by the different dietary CTC concentrations. Blood concentrations of 1 microgram/ml are considered therapeutic, so it is likely that 1% CTC-medicated pellets will be adequate for treating chlamydiosis in these species.

  10. The origin of pelletal lapilli in explosive kimberlite eruptions.

    PubMed

    Gernon, T M; Brown, R J; Tait, M A; Hincks, T K

    2012-05-15

    Kimberlites are volatile-rich magmas from mantle depths of ≥ 150  km and are the primary source of diamonds. Kimberlite volcanism involves the formation of diverging pipes or diatremes, which are the locus of high-intensity explosive eruptions. A conspicuous and previously enigmatic feature of diatreme fills are 'pelletal lapilli'--well-rounded clasts consisting of an inner 'seed' particle with a complex rim, thought to represent quenched juvenile melt. Here we show that these coincide with a transition from magmatic to pyroclastic behaviour, thus offering fundamental insights into eruption dynamics and constraints on vent conditions. We propose that pelletal lapilli are formed when fluid melts intrude into earlier volcaniclastic infill close to the diatreme root zone. Intensive degassing produces a gas jet in which locally scavenged particles are simultaneously fluidised and coated by a spray of low-viscosity melt. A similar origin may apply to pelletal lapilli in other alkaline volcanic rocks, including carbonatites, kamafugites and melilitites.

  11. Microwave measurement of the mass of frozen hydrogen pellets

    DOEpatents

    Talanker, Vera; Greenwald, Martin

    1990-01-01

    A nondestructive apparatus and method for measuring the mass of a moving object, based on the perturbation of the dielectric character of a resonant microwave cavity caused by the object passing through the cavity. An oscillator circuit is formed with a resonant cavity in a positive feedback loop of a microwave power amplifier. The moving object perturbs the resonant characteristics of the cavity causing a shift in the operating frequency of the oscillator proportional to the ratio of the pellet volume to the volume of the cavity. Signals from the cavity oscillation are mixed with a local oscillator. Then the IF frequency from the mixer is measured thereby providing a direct measurement of pellet mass based upon known physical properties and relationships. This apparatus and method is particularly adapted for the measurement of frozen hydrogen pellets.

  12. Behavior of Quartz and Carbon Black Pellets at Elevated Temperatures

    NASA Astrophysics Data System (ADS)

    Li, Fei; Tangstad, Merete

    This paper studies the quartz and carbon black pellets at elevated temperature with varying temperature and gas atmosphere. High-purity quartz and commercial ultra-pure carbon black was mixed (carbon content vet. 15%), and then pelletized into particles of l-3mm in diameter. The stoichiometric analysis of the pellet during heating is studied in thermogravimetric analysis (TGA) furnace at different temperature in CO and Ar atmosphere. The microstructure, phase changes and element content of sample before/after heating is characterized by X-ray diffraction, scanning electron microscope, X-ray fluorescence and LECO analyzer. The reaction process can be divided into two stages. Higher temperature and argon atmosphere are the positive parameters for SiC formation.

  13. Environmental factors affect the activity of biocontrol agents against ochratoxigenic Aspergillus carbonarius on wine grape.

    PubMed

    De Curtis, F; de Felice, D V; Ianiri, G; De Cicco, V; Castoria, R

    2012-09-17

    The influence of temperature and relative humidity (RH) on the activity of three biocontrol agents-the yeast Metschnikowia pulcherrima LS16 and two strains of the yeast-like fungus Aureobasidium pullulans LS30 and AU34-2-against infection by A. carbonarius and ochratoxin A (OTA) accumulation in wine grape berries was investigated in lab-scale experiments. The presence of wounds on grape skin dramatically favored infection of berries by A. carbonarius strain A1102, since unwounded berries showed very low levels of infection at all conditions of RH and temperature tested. Artificially wounded berries pre-treated with the biocontrol agents were inoculated with the ochratoxigenic A. carbonarius strain A1102 and were incubated for 5 days at two levels of RH (60% and 100%) and three different temperatures (20, 25 and 30 °C). The three biocontrol agents were able to prevent infections at 60% RH and 20 °C. At 60% RH and 25 °C only strain AU34-2 achieved some protection on day 5, whereas at 30 °C a limited biocontrol efficacy was evident only up to day 2. At 100% RH, LS16, LS30 and AU34-2 showed effective protection of grape berries at 20 °C until the 5th day of incubation. The three biocontrol agents achieved significant protection at higher temperatures only until the 2nd day after the beginning of the experiment: all three strains at 25 °C, and only strain LS16 at 30 °C. After 5 days, the three biocontrol agents were able to significantly reduce the level of OTA in berries at all the conditions tested. This occurred even when protection from infection was not significant, except at 30 °C and 100% of RH for all the three strains, and at 25 °C and 100% of RH for strain LS16. The biocontrol agents displayed a higher rate of colonization on grape berries at 20 and 25 °C than at 30 °C. The higher value of RH (100%) appeared to increase the rate of colonization, in particular at 20 and 25 °C. Taken together, our results emphasize the significant influence of

  14. Melanized fungi in human disease.

    PubMed

    Revankar, Sanjay G; Sutton, Deanna A

    2010-10-01

    Melanized or dematiaceous fungi are associated with a wide variety of infectious syndromes, including chromoblastomycosis, mycetoma, and phaeohyphomycosis. [corrected]. Many are soil organisms and are generally distributed worldwide, though certain species appear to have restricted geographic ranges. Though they are uncommon causes of disease, melanized fungi have been increasingly recognized as important pathogens, with most reports occurring in the past 20 years. The spectrum of diseases with which they are associated has also broadened and includes allergic disease, superficial and deep local infections, pneumonia, brain abscess, and disseminated infection. For some infections in immunocompetent individuals, such as allergic fungal sinusitis and brain abscess, they are among the most common etiologic fungi. Melanin is a likely virulence factor for these fungi. Diagnosis relies on careful microscopic and pathological examination, as well as clinical assessment of the patient, as these fungi are often considered contaminants. Therapy varies depending upon the clinical syndrome. Local infection may be cured with excision alone, while systemic disease is often refractory to therapy. Triazoles such as voriconazole, posaconazole, and itraconazole have the most consistent in vitro activity. Further studies are needed to better understand the pathogenesis and optimal treatment of these uncommon infections.

  15. Melanized Fungi in Human Disease

    PubMed Central

    Revankar, Sanjay G.; Sutton, Deanna A.

    2010-01-01

    Summary: Melanized or dematiaceous fungi are associated with a wide variety of infectious syndromes. Many are soil organisms and are generally distributed worldwide, though certain species appear to have restricted geographic ranges. Though they are uncommon causes of disease, melanized fungi have been increasingly recognized as important pathogens, with most reports occurring in the past 20 years. The spectrum of diseases with which they are associated has also broadened and includes allergic disease, superficial and deep local infections, pneumonia, brain abscess, and disseminated infection. For some infections in immunocompetent individuals, such as allergic fungal sinusitis and brain abscess, they are among the most common etiologic fungi. Melanin is a likely virulence factor for these fungi. Diagnosis relies on careful microscopic and pathological examination, as well as clinical assessment of the patient, as these fungi are often considered contaminants. Therapy varies depending upon the clinical syndrome. Local infection may be cured with excision alone, while systemic disease is often refractory to therapy. Triazoles such as voriconazole, posaconazole, and itraconazole have the most consistent in vitro activity. Further studies are needed to better understand the pathogenesis and optimal treatment of these uncommon infections. PMID:20930077

  16. What Defines the "Kingdom" Fungi?

    PubMed

    Richards, Thomas A; Leonard, Guy; Wideman, Jeremy G

    2017-06-01

    The application of environmental DNA techniques and increased genome sequencing of microbial diversity, combined with detailed study of cellular characters, has consistently led to the reexamination of our understanding of the tree of life. This has challenged many of the definitions of taxonomic groups, especially higher taxonomic ranks such as eukaryotic kingdoms. The Fungi is an example of a kingdom which, together with the features that define it and the taxa that are grouped within it, has been in a continual state of flux. In this article we aim to summarize multiple lines of data pertinent to understanding the early evolution and definition of the Fungi. These include ongoing cellular and genomic comparisons that, we will argue, have generally undermined all attempts to identify a synapomorphic trait that defines the Fungi. This article will also summarize ongoing work focusing on taxon discovery, combined with phylogenomic analysis, which has identified novel groups that lie proximate/adjacent to the fungal clade-wherever the boundary that defines the Fungi may be. Our hope is that, by summarizing these data in the form of a discussion, we can illustrate the ongoing efforts to understand what drove the evolutionary diversification of fungi.

  17. Lectins in human pathogenic fungi.

    PubMed

    Gallegos, Belém; Martínez, Ruth; Pérez, Laura; Del Socorro Pina, María; Perez, Eduardo; Hernández, Pedro

    2014-01-01

    Lectins are carbohydrate-binding proteins widely distributed in nature. They constitute a highly diverse group of proteins consisting of many different protein families that are, in general, structurally unrelated. In the last few years, mushroom and other fungal lectins have attracted wide attention due to their antitumour, antiproliferative and immunomodulatory activities. The present mini-review provides concise information about recent developments in understanding lectins from human pathogenic fungi. A bibliographic search was performed in the Science Direct and PubMed databases, using the following keywords "lectin", "fungi", "human" and "pathogenic". Lectins present in fungi have been classified; however, the role played by lectins derived from human pathogenic fungi in infectious processes remains uncertain; thus, this is a scientific field requiring more research. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  18. Formation of particulate matter monitoring during combustion of wood pellete with additives

    NASA Astrophysics Data System (ADS)

    Palacka, Matej; Holubčík, Michal; Vician, Peter; Jandačka, Jozef

    2016-06-01

    Application additives into the material for the production of wood pellets achieve an improvement in some properties such as pellets ash flow temperature and abrasion resistance. Additives their properties influence the course of combustion, and have an impact on the results of issuance. The experiment were selected additives corn starch and dolomite. Wood pellets were produced in the pelleting press and pelletizing with the additives. Selected samples were tested for the production of particulate matter (PM) during their direct burn. The paper analyzing a process of producing wood pellets and his effect on the final properties.

  19. Coaxial pellets for metallic impurity injection on the large helical device

    SciTech Connect

    Huang, X. L. Zhang, H. M.; Morita, S.; Oishi, T.; Goto, M.

    2014-11-15

    Two coaxial pellets with tungsten inserted into graphite carbon and polyethylene (PE) tubes are compared for tungsten spectroscopic study in the Large Helical Device. The tungsten pellet with carbon tube causes plasma collapse, while that with PE tube smoothly ablates without collapse. The deposition profile of the pellets is analyzed with a help of pellet ablation spectroscopy. It is found that the tungsten pellet with carbon tube can significantly penetrate into the core plasma and leads to the plasma collapse. A tungsten spectrum with radial profile is successfully observed when the tungsten pellet with PE tube is used.

  20. Use of green fluorescent protein-based reporters to monitor balanced production of antifungal compounds in the biocontrol agent Pseudomonas fluorescens CHA0.

    PubMed

    Baehler, E; Bottiglieri, M; Péchy-Tarr, M; Maurhofer, M; Keel, C

    2005-01-01

    To develop reporter constructs based on stable and unstable variants of the green fluorescent protein (GFP) for monitoring balanced production of antifungal compounds that are crucial for the capacity of the root-colonizing Pseudomonas fluorescens strain CHA0 to control plant diseases caused by soil-borne pathogenic fungi. Pseudomonas fluorescens CHA0 produces the three antifungal metabolites 2,4-diacetylphloroglucinol (DAPG), pyoluteorin (PLT) and pyrrolnitrin (PRN). The gfp[mut3] and gfp[AAV] reporter genes were fused to the promoter regions of the DAPG, PLT and PRN biosynthetic genes. The reporter fusions were then used to follow the kinetics of expression of the three antifungal metabolites in a microplate assay. DAPG and PLT were found to display an inverse relationship in which each metabolite activates its own biosynthesis while repressing the synthesis of the other metabolite. PRN appears not to be involved in this balance. However, the microbial and plant phenolic metabolite salicylate was found to interfere with the expression of both DAPG and PLT. The results obtained provide evidence that P. fluorescens CHA0 may keep the antifungal compounds DAPG and PLT at a fine-tuned balance that can be affected by certain microbial and plant phenolics. To our knowledge, the present study is the first to use stable and unstable GFP variants to study antibiotic gene expression in a biocontrol pseudomonad. The developed reporter fusions will be a highly valuable tool to study in situ expression of this bacterial biocontrol trait on plant roots, i.e. at the site of pathogen suppression.