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Sample records for pelletized biocontrol fungi

  1. 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

  2. Mycelial pellet formation by edible ascomycete filamentous fungi, Neurospora intermedia.

    PubMed

    Nair, Ramkumar B; Lennartsson, Patrik R; Taherzadeh, Mohammad J

    2016-12-01

    Pellet formation of filamentous fungi in submerged culture is an imperative topic of fermentation research. In this study, we report for the first time the growth of filamentous ascomycete fungus, Neurospora intermedia in its mycelial pellet form. In submerged culture, the growth morphology of the fungus was successfully manipulated into growing as pellets by modifying various cultivation conditions. Factors such as pH (2.0-10.0), agitation rate (100-150 rpm), carbon source (glucose, arabinose, sucrose, and galactose), the presence of additive agents (glycerol and calcium chloride) and trace metals were investigated for their effect on the pellet formation. Of the various factors screened, uniform pellets were formed only at pH range 3.0-4.0, signifying it as the most influential factor for N. intermedia pellet formation. The average pellet size ranged from 2.38 ± 0.12 to 2.86 ± 0.38 mm. The pellet formation remained unaffected by the inoculum type used and its size showed an inverse correlation with the agitation rate of the culture. Efficient glucose utilization was observed with fungal pellets, as opposed to the freely suspended mycelium, proving its viability for fast-fermentation processes. Scale up of the pelletization process was also carried out in bench-scale airlift and bubble column reactors (4.5 L).

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  4. 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. PMID:25281814

  5. Arbuscular mycorrhizal fungi: potential biocontrol agents against the damaging root hemiparasite Pedicularis kansuensis?

    PubMed

    Sui, Xiao-Lin; Li, Ai-Rong; Chen, Yan; Zhuo, Lu; Liu, Yan-Yan

    2014-04-01

    Spatial expansion of root hemiparasitic Pedicularis kansuensis in Bayanbulak Grassland of Xinjiang Uygur Autonomous Region (China) has caused great loss of herbage yield and has threatened the local livestock industry. Current management practices using manual eradication and chemical control have been proved problematic. Arbuscular mycorrhizal (AM) fungi have been suggested to be potential biocontrol agents against a number of plant pests, but experimental evidence is lacking against weedy P. kansuensis. In this study, we tested the hypothesis that inoculation with AM fungi will cause growth depression in P. kansuensis and reduce its damage to host plants. Based on the confirmation of AM status and host community of the hemiparasite in the field, a pot cultivation experiment was conducted to test the influence of an AM fungus (Glomus mosseae) on growth of P. kansuensis and the parasitized host (Elymus nutans). AM colonization was observed in roots of P. kansuensis, but the levels were much lower than those of its adjacent host species. A negative correlation between AM levels and the numbers of haustoria was detected for the field samples of the hemiparasite. Strong suppression of haustorium formation, a significant reduction in plant dry weight (DW), as well as marked reduction in the survival rate of P. kansuensis after inoculation with AM fungi was observed. In contrast, inoculation with G. mosseae increased root DW and whole plant DW of parasitized host plants. Our findings demonstrated significantly repressive effects of AM fungi on growth performance of P. kansuensis with and without the presence of a host. The potential of AM fungi as biocontrol agents against the damaging hemiparasite was confirmed.

  6. 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.

  7. 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. PMID:19204894

  8. 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

  9. 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

  10. 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. PMID:26635750

  11. 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

    2015-07-01

    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. PMID:25863340

  12. Identification of a new biocontrol gene in Trichoderma atroviride: the role of an ABC transporter membrane pump in the interaction with different plant-pathogenic fungi.

    PubMed

    Ruocco, Michelina; Lanzuise, Stefania; Vinale, Francesco; Marra, Roberta; Turrà, David; Woo, Sheridan Lois; Lorito, Matteo

    2009-03-01

    Successful biocontrol interactions often require that the beneficial microbes involved are resistant or tolerant to a variety of toxicants, including antibiotics produced by themselves or phytopathogens, plant antimicrobial compounds, and synthetic chemicals or contaminants. The ability of Trichoderma spp., the most widely applied biocontrol fungi, to withstand different chemical stresses, including those associated with mycoparasitism, is well known. In this work, we identified an ATP-binding cassette transporter cell membrane pump as an important component of the above indicated resistance mechanisms that appears to be supported by an extensive and powerful cell detoxification system. The encoding gene, named Taabc2, was cloned from a strain of Trichoderma atroviride and characterized. Its expression was found to be upregulated in the presence of pathogen-secreted metabolites, specific mycotoxins and some fungicides, and in conditions that stimulate the production in Trichoderma spp. of antagonism-related factors (toxins and enzymes). The key role of this gene in antagonism and biocontrol was demonstrated by the characterization of the obtained deletion mutants. They suffered an increased susceptibility to inhibitory compounds either secreted by pathogenic fungi or possibly produced by the biocontrol microbe itself and lost, partially or entirely, the ability to protect tomato plants from Pythium ultimum and Rhizoctonia solani attack.

  13. 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.

  14. 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. PMID:24813508

  15. 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

    2015-07-01

    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. PMID:26050784

  16. 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

    2015-07-01

    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.

  17. 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

  18. 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.

  19. 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

  20. 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

  1. Mycorrhizal fungi and Trichoderma harzianum as biocontrol agents for suppression of Rhizoctonia solani damping-off disease of tomato.

    PubMed

    Amer, M A; Abou-El-Seoud, I I

    2008-01-01

    The objective of the present work was to examine the interaction between arbuscular mycorrhizal fungus (AMF) Glomus intraradices and Trichoderma harzianum in soil. Soil application with T. harzianum or/and G. intraradices significantly reduced tomato seedlings damping-off incited by Rhizoctonia solani. Moreover, more pronounced disease suppression was obtained when both bioagents were applied together. Application of T. harzianum to healthy or inoculated seedlings significantly increased phosphorous supply, which resulted in higher yield, associated with the accumulation of high phosphorus levels in tissues of tomato plants (4.7- 6.5-fold), compared with low P supply. Inoculation with both bioagents in the presence or absence of the pathogen gave significant rise (2.1 - 2.2-fold), compared with low P levels. Root length of inoculated plants treated with T. harzianum or G. intraradices appeared longer than those of inoculated untreated plants at all P levels. Phosphorus uptake (mg P/plant) of tomato plant increased in all treatments with increasing of P levels with R. solani, T. harzianum or their combination and untreated plants have vigorous response to phosphorus fertilization. At low P levels, there was a significant difference between treatments, P uptake of tomato plants inoculated with AMF, T. harzianum or in combination, either in absence or in the presence of the tested pathogen showed highly significant increase, compared to untreated plant, infected plants with pathogen, T. harzianum, and their mixture. At high P levels, there was no significant difference between control and both AMF and T. harzianum, either individually in health plants or in combination with the pathogen. Eventually, results presented here substantiate other studies reporting enhanced biocontrol performance.

  2. 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.

  3. Fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  4. 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.

  5. 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.…

  6. 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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  8. 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)

  9. 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.

  10. Commercialization and implementation of biocontrol.

    PubMed

    Fravel, D R

    2005-01-01

    Although the number of biocontrol products is increasing, these products still represent only about 1% of agricultural chemical sales. Yet these are important contributions because biocontrol agents offer disease management alternatives with different mechanisms of action than chemical pesticides. Trends in research include the increased use of biorational screening processes to identify microorganisms with potential for biocontrol, increased testing under semicommercial and commercial production conditions, increased emphasis on combining biocontrol strains with each other and with other control methods, integrating biocontrol into an overall system.

  11. 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. PMID:27131325

  12. 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.

  13. 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. PMID:27688836

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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". PMID:27570260

  19. 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

  20. 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.

  1. Radation shielding pellets

    DOEpatents

    Coomes, Edmund P.; Luksic, Andrzej T.

    1988-01-01

    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.

  2. 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.

  3. 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.

  4. 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. PMID:23711366

  5. Induced systemic resistance and plant responses to fungal biocontrol agents.

    PubMed

    Shoresh, Michal; Harman, Gary E; Mastouri, Fatemeh

    2010-01-01

    Biocontrol fungi (BCF) are agents that control plant diseases. These include the well-known Trichoderma spp. and the recently described Sebacinales spp. They have the ability to control numerous foliar, root, and fruit pathogens and even invertebrates such as nematodes. However, this is only a subset of their abilities. We now know that they also have the ability to ameliorate a wide range of abiotic stresses, and some of them can also alleviate physiological stresses such as seed aging. They can also enhance nutrient uptake in plants and can substantially increase nitrogen use efficiency in crops. These abilities may be more important to agriculture than disease control. Some strains also have abilities to improve photosynthetic efficiency and probably respiratory activities of plants. All of these capabilities are a consequence of their abilities to reprogram plant gene expression, probably through activation of a limited number of general plant pathways.

  6. Elevated activity of dolichyl phosphate mannose synthase enhances biocontrol abilities of Trichoderma atroviride.

    PubMed

    Zembek, Patrycja; Perlinska-Lenart, Urszula; Brunner, Kurt; Reithner, Barbara; Palamarczyk, Grazyna; Mach, Robert L; Kruszewska, Joanna S

    2011-12-01

    Antagonism of Trichoderma spp. against phytopathogenic fungi is widely exploited for biocontrol of plant diseases. A crucial role in the biocontrol mechanism is attributed to cell-wall-degrading enzymes secreted by Trichoderma spp. Therefore, more efficient production and secretion of the enzymes should elevate the biocontrol abilities of Trichoderma spp. Because the majority of secretory hydrolases are glycoproteins, it has been postulated that the posttranslational modification of these proteins could constitute a bottleneck in their production and secretion. Our previous study showed that improvement of O-glycosylation elevated protein secretion by Trichoderma reesei. In this study, we enhanced the biocontrol abilities of T. atroviride P1 against plant pathogens by overexpressing the Saccharomyces cerevisiae DPM1 gene coding for dolichyl phosphate mannose (DPM) synthase, a key enzyme in the O-glycosylation pathway. The transformants we obtained showed doubled DPM synthase activity and, at the same time, significantly elevated cellulolytic activity. They also revealed an improved antifungal activity against the plant pathogen Pythium ultimum.

  7. 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.

  8. 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.

  9. 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. PMID:23435902

  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. Combining UV-C treatment with biocontrol yeast to control postharvest decay of melon.

    PubMed

    Huang, Ke; Zou, Yong; Luo, Jie; Liu, Yiqing

    2015-09-01

    Significant losses in harvested melon can be directly attributable to decay fungi. In the present study, the use of UV-C treatment combined with biocontrol yeast, Pichia cecembensis, was evaluated for their ability to control postharvest decay of melon fruits after they were artificially inoculated with Fusarium oxysporum and Alternaria alternata. Natural infection of fruit was also assessed. As a stand-alone treatment, UV-C or P. cecembensis significantly reduced Fusarium rot and Alternaria rot, and also the level of natural infection on melon fruit, relative to the untreated control. The combination of UV-C or P. cecembensis, however, provided a superior level of decay control on artificially inoculated and naturally infected fruit, compared to either treatment alone. None of the treatments impaired fruit quality. Integrating the use of UV-C treatment with biocontrol yeast has potential as an effective method to control postharvest decay of melon.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  13. 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.

  14. 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

  15. 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.

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

    PubMed

    Sun, Ming; Wang, Xiaoyan; Luo, Jianxun

    2012-08-01

    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.

  17. 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

  18. Gut fungi.

    PubMed

    Brent Heath, I

    1988-07-01

    Herbivores consume large quantities of cellulose and other plant cell wall (fibre) carbohydrates yet generally lack the enzymes to digest them. This has led to the evolution of specialized portions of the gut, such as the rumen and caecum, which contain large populations of digestive anaerobic microorganisms. Diverse bacteria and protists from this environment have been studied for over a hundred years but it is only recently that a significant population of highly specialized flagellate fungi have been identified. These fungi are important in fibre digestion. Their diversity, properties, activities, phylogeny and possible economic significance are the subjects of this review.

  19. 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.

  20. 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.

  1. 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.

  2. Pellet injector development at ORNL

    SciTech Connect

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

    1992-12-31

    Plasma fueling systems for magnetic confinement experiments are under development at Oak Ridge National Laboratory (ORNL). ORNL has recently provided a four-shot tritium pellet injector with up to 4-mm-diam capability for the Tokamak Fusion Test Reactor (TFTR). This injector, which is based on the in situ condensation technique for pellet formation, features three single-stage gas guns that have been qualified in deuterium at up to 1.7 km/s and a two-stage light gas gun driver that has been operated at 2.8-km/s pellet speeds for deep penetration in the high-temperature TFTR supershot regime. Performance improvements to the centrifugal pellet injector for the Tore Supra tokamak are being made by modifying the storage-type pellet feed system, which has been redesigned to improve the reliability of delivery of pellets and to extend operation to longer pulse durations (up to 400 pellets). Two-stage light gas guns and electron-beam (e-beam) rocket accelerators for speeds in the range from 2 to 10 km/s are also under development. A repeating, two-stage light gas gun that has been developed can accelerate low-density plastic pellets at a 1-Hz repetition rate to speeds of 3 km/s. In a collaboration with ENEA-Frascati, a test facility has been prepared to study repetitive operation of a two-stage gas gun driver equipped with an extrusion-type deuterium pellet source. Extensive testing of the e-beam accelerator has demonstrated a parametric dependence of propellant burn velocity and pellet speed, in accordance with a model derived from the neutral gas shielding theory for pellet ablation in a magnetized plasma.

  3. Pellet injector development at ORNL

    SciTech Connect

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

    1992-01-01

    Plasma fueling systems for magnetic confinement experiments are under development at Oak Ridge National Laboratory (ORNL). ORNL has recently provided a four-shot tritium pellet injector with up to 4-mm-diam capability for the Tokamak Fusion Test Reactor (TFTR). This injector, which is based on the in situ condensation technique for pellet formation, features three single-stage gas guns that have been qualified in deuterium at up to 1.7 km/s and a two-stage light gas gun driver that has been operated at 2.8-km/s pellet speeds for deep penetration in the high-temperature TFTR supershot regime. Performance improvements to the centrifugal pellet injector for the Tore Supra tokamak are being made by modifying the storage-type pellet feed system, which has been redesigned to improve the reliability of delivery of pellets and to extend operation to longer pulse durations (up to 400 pellets). Two-stage light gas guns and electron-beam (e-beam) rocket accelerators for speeds in the range from 2 to 10 km/s are also under development. A repeating, two-stage light gas gun that has been developed can accelerate low-density plastic pellets at a 1-Hz repetition rate to speeds of 3 km/s. In a collaboration with ENEA-Frascati, a test facility has been prepared to study repetitive operation of a two-stage gas gun driver equipped with an extrusion-type deuterium pellet source. Extensive testing of the e-beam accelerator has demonstrated a parametric dependence of propellant burn velocity and pellet speed, in accordance with a model derived from the neutral gas shielding theory for pellet ablation in a magnetized plasma.

  4. 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.…

  5. [Shotgun injury--multiple pellets].

    PubMed

    Hejna, P; Pleskot, J

    2009-01-01

    Both typical and less frequent features of gunshot wounds caused by shotguns are reported in the following article. The pattern of shotgun injury predominantly depends on gauge, choke, number and diameter of used pellets, muzzle-victim distance and on character of the afflicted area of the body. Characteristic ballistic properties of shotgun pellets, their wounding potential and significance in forensic patology are presented.

  6. 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.

  7. 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.

  8. 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. PMID:24530369

  9. The global regulator genes from biocontrol strain Serratia plymuthica IC1270: cloning, sequencing, and functional studies.

    PubMed

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

    2004-08-01

    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.

  10. 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. PMID:26880001

  11. 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.

  12. Commercialization of postharvest biocontrol: barriers and opportunities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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. ...

  13. Biocontrol of avocado dematophora root rot by antagonistic Pseudomonas fluorescens PCL1606 correlates with the production of 2-hexyl 5-propyl resorcinol.

    PubMed

    Cazorla, Francisco M; Duckett, Simon B; Bergström, Ed T; Noreen, Sadaf; Odijk, Roeland; Lugtenberg, Ben J J; Thomas-Oates, Jane E; Bloemberg, Guido V

    2006-04-01

    A collection of 905 bacterial isolates from the rhizospheres of healthy avocado trees was obtained and screened for antagonistic activity against Dematophora necatrix, the cause of avocado Dematophora root rot (also called white root rot). A set of eight strains was selected on the basis of growth inhibitory activity against D. necatrix and several other important soilborne phytopathogenic fungi. After typing of these strains, they were classified as belonging to Pseudomonas chlororaphis, Pseudomonas fluorescens, and Pseudomonas putida. The eight antagonistic Pseudomonas spp. were analyzed for their secretion of hydrogen cyanide, hydrolytic enzymes, and antifungal metabolites. P. chlororaphis strains produced the antibiotic phenazine-1-carboxylic acid and phenazine-1-carboxamide. Upon testing the biocontrol ability of these strains in a newly developed avocado-D. necatrix test system and in a tomato-F oxysporum test system, it became apparent that P. fluorescens PCL1606 exhibited the highest biocontrol ability. The major antifungal activity produced by strain P. fluorescens PCL1606 did not correspond to any of the major classes of antifungal antibiotics produced by Pseudomonas biocontrol strains. This compound was purified and subsequently identified as 2-hexyl 5-propyl resorcinol (HPR). To study the role of HPR in biocontrol activity, two Tn5 mutants of P. fluorescens PCL1606 impaired in antagonistic activity were selected. These mutants were shown to impair HRP production and showed a decrease in biocontrol activity. As far as we know, this is the first report of a Pseudomonas biocontrol strain that produces HPR in which the production of this compound correlates with its biocontrol activity.

  14. Pelletizing of sulfide molybdenite concentrates

    NASA Astrophysics Data System (ADS)

    Palant, A. A.

    2007-04-01

    The results of a pelletizing investigation using various binding components (water, syrup, sulfite-alcohol distillery grains, and bentonite) of the flotation sulfide molybdenite concentrate (˜84% MoS2) from the Mongolian deposit are discussed. The use of syrup provides rather high-strength pellets (>3 N/pellet or >300 g/pellet) of the required size (2 3 mm) for the consumption of 1 kg binder per 100 kg concentrate. The main advantage of the use of syrup instead of bentonite is that the molybdenum cinder produced by oxidizing roasting of raw ore materials is not impoverished due to complete burning out of the syrup. This fact exerts a positive effect on the subsequent hydrometallurgical process, decreasing molybdenum losses related to dump cakes.

  15. [Resistant fungi].

    PubMed

    Vehreschild, M J G T; Cornely, O A

    2015-11-01

    Particularly in the area of hematology/oncology and intensive care medicine, infections due to resistant fungi are to be expected. Emergence of resistance in fungi is a less dynamic process than in bacteria; it can, however, have an equally important impact on treatment strategies. In the following article, the most important resistance patterns of yeasts and molds (Candida albicans , Aspergillus fumigatus, the order Mucorales and the genus Fusarium) will be presented and discussed. Their diagnosis mostly being based on blood cultures, resistance testing for yeasts is usually readily available. Culture-based therapeutic adjustments in mold infections are, however, only rarely possible, as most antifungal therapies for these infections are initiated on an empirical basis after identification of typical infiltrates on a CT scan. Response to therapy is then evaluated on the basis of clinical signs and symptoms in combination with follow-up CT scans. In case of therapeutic failure or appearance of suspicious infiltrates under antifungal prophylaxis, an open or CT-guided biopsy is recommended to allow efficient adaptation of antifungal treatment. In individual cases, particularly in patients diagnosed with mucormycosis, resection of the focus of infection may be necessary to achieve a satisfactory treatment response.

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. Mechanisms Involved in Nematode Control by Endophytic Fungi.

    PubMed

    Schouten, Alexander

    2016-08-01

    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. PMID:27296146

  1. Mechanisms Involved in Nematode Control by Endophytic Fungi.

    PubMed

    Schouten, Alexander

    2016-08-01

    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.

  2. 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.

  3. Second jet workshop on pellet injection: pellet fueling program in the United States. Summary

    SciTech Connect

    Milora, S.L.

    1983-01-01

    S. Milora described the US programme on pellet injection. It has four parts: (1) a confinement experimental program; (2) pellet injector development; (3) theoretical support; and (4) tritium pellet study for TFTR.

  4. 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.

  5. Complete Genome Sequence of Biocontrol Strain Pseudomonas fluorescens LBUM 223

    PubMed Central

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

    2015-01-01

    Pseudomonas fluorescens LBUM 223 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 LBUM 223. PMID:25953163

  6. 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

  7. Role of gluconic acid production in the regulation of biocontrol traits of Pseudomonas fluorescens CHA0.

    PubMed

    de Werra, Patrice; Péchy-Tarr, Maria; Keel, Christoph; Maurhofer, Monika

    2009-06-01

    The rhizobacterium Pseudomonas fluorescens CHA0 promotes the growth of various crop plants and protects them against root diseases caused by pathogenic fungi. The main mechanism of disease suppression by this strain is the production of the antifungal compounds 2,4-diacetylphloroglucinol (DAPG) and pyoluteorin (PLT). Direct plant growth promotion can be achieved through solubilization of inorganic phosphates by the production of organic acids, mainly gluconic acid, which is one of the principal acids produced by Pseudomonas spp. The aim of this study was to elucidate the role of gluconic acid production in CHA0. Therefore, mutants were created with deletions in the genes encoding glucose dehydrogenase (gcd) and gluconate dehydrogenase (gad), required for the conversion of glucose to gluconic acid and gluconic acid to 2-ketogluconate, respectively. These enzymes should be of predominant importance for rhizosphere-colonizing biocontrol bacteria, as major carbon sources provided by plant root exudates are made up of glucose. Our results show that the ability of strain CHA0 to acidify its environment and to solubilize mineral phosphate is strongly dependent on its ability to produce gluconic acid. Moreover, we provide evidence that the formation of gluconic acid by CHA0 completely inhibits the production of PLT and partially inhibits that of DAPG. In the Deltagcd mutant, which does not produce gluconic acid, the enhanced production of antifungal compounds was associated with improved biocontrol activity against take-all disease of wheat, caused by Gaeumannomyces graminis var. tritici. This study provides new evidence for a close association of gluconic acid metabolism with antifungal compound production and biocontrol activity in P. fluorescens CHA0.

  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. 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.

  10. 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. PMID:25679537

  11. 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

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

    PubMed

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

    2015-09-01

    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.

  13. 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. PMID:27121573

  14. Biocontrol activity of Paenibacillus polymyxa AC-1 against Pseudomonas syringae and its interaction with Arabidopsis thaliana.

    PubMed

    Hong, Chi Eun; Kwon, Suk Yoon; Park, Jeong Mee

    2016-04-01

    Paenibacillus polymyxa AC-1 (AC-1) is a plant growth-promoting rhizobacterium (PGPR) that has been used as a soil inoculant for biocontrol of plant pathogenic fungi and to promote plant growth. In this study, we examine the effects of AC-1 on the bacterial phytopathogen Pseudomonas syringae and internal colonization of AC-1 by counting bacterial populations that colonize plants. AC-1 inhibited the growth of both P. syringae pv. tomato DC3000 (Pst) and P. syringae pv. tabaci (Pta) in a concentration-dependent manner in in vitro assays. Upon treatment of AC-1 dropping at root tip of axenically grown Arabidopsis, we found that most of the AC-1 was detected in interior of leaves of Arabidiopsis plants rather than roots after 5 days post infection, indicating systemic spreading of AC-1 occur. We examined further AC-1 colonization patterns in Arabidopsis mutants deficient in phytohormone signaling pathways. These results indicated that abscisic acid (ABA) and jasmonic acid (JA) signaling pathways positively and negatively contributed, respectively, to AC-1 colonization of leaves, whereas epiphytic accumulation of AC-1 around root tissues was not affected. This study shows that AC-1 is an effective biocontrol agent to suppress P. syringae growth, possibly owing to its colonization patterns as a leaf-inhabiting endophyte. The results showed in this work will help to expand our understanding of the mode of action of AC-1 as a biological control agent and consequently, its application in agriculture.

  15. Nonribosomal Peptides, Key Biocontrol Components for Pseudomonas fluorescens In5, Isolated from a Greenlandic Suppressive Soil

    PubMed Central

    Michelsen, Charlotte F.; Watrous, Jeramie; Glaring, Mikkel A.; Kersten, Roland; Koyama, Nobuhiro

    2015-01-01

    ABSTRACT 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. PMID:25784695

  16. Pellet fueling development at ORNL

    SciTech Connect

    Combs, S.K.; Milora, S.L.; Foster, C.A.; Schuresko, D.D.; Foust, C.R.; Simmons, D.W.; Beard, D.S.

    1986-09-01

    Advanced plasma fueling systems for magnetic confinement devices are being developed at the Oak Ridge National Laboratory (ORNL). The general approach is that of producing and accelerating frozen hydrogenic pellets at speeds in the range of 1-2 km/s and higher. Two specific concepts are under development: (1) high-speed pneumatic acceleration; and (2) mechanical (centrifugal) acceleration. Both approaches are being pursued to meet the projected pellet size and delivery rates for major near-term plasma confinement devices, such as the Tokamak Fusion Test Reactor (TFTR), Tore Supra, the Joint European Torus (JET), JT-60, and Doublet III-D (DIII-D), as well as future applications. In addition to these confinement physics related activities, ORNL is pursuing advanced technologies to achieve pellet velocities significantly in excess of the 2-km/s range already attained with pneumatic injectors and has embarked on a development program designed to explore the feasibility of fabricating and accelerating tritium pellets. This paper describes these ongoing activities.

  17. Isolation and identification of actinomycetes from a compost-amended soil with potential as biocontrol agents.

    PubMed

    Cuesta, Gonzalo; García-de-la-Fuente, Rosana; Abad, Manuel; Fornes, Fernando

    2012-03-01

    The search for new biocontrol strategies to inhibit the growth of phytopathogenic microorganisms has become widely widespread due to environmental concerns. Among actinomycetes, Streptomyces species have been extensively studied since they have been recognized as important sources of antibiotics. Actinomycete strains were isolated from a calcareous soil, 2 two-phase olive mill waste ('alperujo') composts, and the compost-amended soil by using selective media, and they were then co-cultured with 5 phytopathogenic fungi and 1 bacterium to perform an in vitro antagonism assay. Forty-nine actinomycete strains were isolated, 12 of them showing a great antagonistic activity towards the phytopathogenic microorganisms tested. Isolated strains were identified by 16S rDNA sequence analysis and phenotypic procedures. Eleven isolates concerned the genus Streptomyces and 1 actinomycete with chitinolytic activity belonged to the genus Lechevalieria. PMID:21190787

  18. Characterization of a new Pseudomonas aeruginosa strain NJ-15 as a potential biocontrol agent.

    PubMed

    Bano, Nazneen; Musarrat, Javed

    2003-05-01

    Phylogenetic characterization of soil isolate NJ-15, based on sequence homology of a partial 746-bp fragment of 16SrDNA amplicon, with the ribosomal database sequences (http://www.msu.edu/RDP/cgis/phylip.cgi), validated the strain as Pseudomonas aeruginosa. The strain NJ-15 produced a substantial amount of indole acetic acid (IAA) in tryptophan-supplemented medium. Besides, the strain also exhibited significant production of both the siderophore and hydrogen cyanide (HCN) on chrome azurol S and King's B media, respectively. The data revealed lower HCN production under iron-limiting conditions vis-à-vis higher HCN release with iron stimulation. Significant growth inhibition of phytopathogenic fungi occurred in the order as Fusarium oxysporum > Trichoderma herizum > Alternaria alternata > Macrophomina phasiolina upon incubation with strain NJ-15 cells. Thus, the secondary metabolites producing new Pseudomonas aeruginosa strain NJ-15 exhibited innate potential of plant growth promotion and biocontrol activities in vitro.

  19. 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.

  20. 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.

  1. 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. PMID:27141751

  2. 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.

  3. 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. PMID:26038303

  4. 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

  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. [Effect of pretreatment by solid-state fermentation of sawdust on the pelletization and pellet's properties].

    PubMed

    Guo, Jingjing; Yuan, Xingzhong; Li, Hui; Li, Changzhu; Xiao, Zhihong; Xiao, Zhihua; Jiang, Longbo; Zeng, Guangming

    2015-10-01

    We pretreated sawdust (Castanopsis fissa Rehd.et Wils) by solid state fermentation (SSF) with Phanerochaete chrysosporium, and then compressed it into pellets with the moisture content of 15% and the pressure of 98 MPa, to solve the problem of low density, low Meyer hardness, high water uptake, and short storage period of pellet in the woody pellet industry. We studied the effects of fermentation time on pelletization and pellets's characteristics (including energy consumption, density, Meyer hardness, and hydrophobicity). SSF affected the heating values of pellet. Compared with fresh sawdust, SSF consumed more energy at the maximal value by 6.98% but saved extrusion energy by 32.19% at the maximum. Meanwhile, SSF could improve the density, Meyer hardness and hydrophobicity of pellet. Pellet made of sawdust pretreated by SSF for 48 d had best quality, beneficial for long-term transportation and storage of pellets. PMID:26964334

  7. [Effect of pretreatment by solid-state fermentation of sawdust on the pelletization and pellet's properties].

    PubMed

    Guo, Jingjing; Yuan, Xingzhong; Li, Hui; Li, Changzhu; Xiao, Zhihong; Xiao, Zhihua; Jiang, Longbo; Zeng, Guangming

    2015-10-01

    We pretreated sawdust (Castanopsis fissa Rehd.et Wils) by solid state fermentation (SSF) with Phanerochaete chrysosporium, and then compressed it into pellets with the moisture content of 15% and the pressure of 98 MPa, to solve the problem of low density, low Meyer hardness, high water uptake, and short storage period of pellet in the woody pellet industry. We studied the effects of fermentation time on pelletization and pellets's characteristics (including energy consumption, density, Meyer hardness, and hydrophobicity). SSF affected the heating values of pellet. Compared with fresh sawdust, SSF consumed more energy at the maximal value by 6.98% but saved extrusion energy by 32.19% at the maximum. Meanwhile, SSF could improve the density, Meyer hardness and hydrophobicity of pellet. Pellet made of sawdust pretreated by SSF for 48 d had best quality, beneficial for long-term transportation and storage of pellets.

  8. 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. PMID:12733629

  9. Genomic Basis of Plant Pathogen Suppression by Biocontrol Pseudomonas Species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Various plant commensal bacterial species, which naturally colonize the plant rhizosphere, are able to suppress fungal, bacterial, viral and even insect plant pathogens. These biocontrol activities are elicited primarily through the production of secreted exoenzymes and secondary metabolites that ma...

  10. 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

  11. Pellet imaging techniques in the ASDEX tokamak

    SciTech Connect

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

    1990-11-01

    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 {ital in} {ital situ} velocity measurements of the pellet as it penetrates the plasma. With time resolution of typically 100 ns and exposures every 50 {mu}s, the evolution of each pellet in a multipellet 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 {ital D}{sub {alpha}}, {ital D}{sub {beta}}, and {ital 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 {ital 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 {ital q} surfaces, but instead are a result of dynamic, nonstationary, ablation process.

  12. 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

  13. 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).

  14. A putative role for fusaric acid in biocontrol of the parasitic angiosperm Orobanche ramosa.

    PubMed

    Bouizgarne, Brahim; El-Maarouf-Bouteau, Hayat; Madiona, Karine; Biligui, Bernadette; Monestiez, Michèle; Pennarun, Anne Marie; Amiar, Zahia; Rona, Jean Pierre; Ouhdouch, Yedir; El Hadrami, Ismaïl; Bouteau, François

    2006-05-01

    Fusarium spp. are ubiquitous fungi found in soil worldwide as both pathogenic and nonpathogenic strains. The signals leading to disease or the absence of disease are poorly understood. We recently showed that fusaric acid (FA), a nonspecific toxin produced by most Fusarium spp., could elicit various plant defense responses at 100 nM without toxic effect. In this study, we checked for the effect of FA on root and root hairs, probable first site of contact between the fungi and the host. Large FA concentrations reduce root and root-hair growth and induce a rapid transient membrane hyperpolarization, followed by a large depolarization, due to the inhibition of H(+)-ATPase currents. Nanomolar concentrations of FA induced only an early transient membrane hyperpolarization of root hairs compatible with the induction of a signal transduction pathway. FA at 10(-7) M failed to induce salicylic acid- and jasmonic acid/ethylene-dependent defense-related genes but inhibited the germination of the angiosperm parasite Orobanche ramosa in contact of FA-pretreated Arabidopsis thaliana seedlings. These data suggest that FA at nontoxic concentrations could activate signal transduction components necessary for plant-defense responses that could contribute to biocontrol activity of Fusarium spp.

  15. 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. PMID:25756527

  16. 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. PMID:27565489

  17. 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

  18. 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

  19. 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

  20. Pellet Injection into MST RFP Plasmas

    NASA Astrophysics Data System (ADS)

    Wyman, M. D.; Chapman, B. E.; Craig, D.; Ennis, D. A.; O'Connell, R.; Oliva, S. P.; Prager, S. C.; Reardon, J. C.; Sarff, J. S.; Combs, S. K.; Baylor, L. R.; Fehling, D. T.; Fisher, P. W.; Foust, C. R.; Rasmussen, D. A.; Wilgen, J. B.; Brower, D. L.; Ding, W. X.

    2002-11-01

    A four-barrel cryogenic pellet injector, designed and built by Oak Ridge National Laboratory, has been installed on MST. The injector is a pipe gun utilizing high-pressure hydrogen gas for acceleration of pellets. Presently, the two barrels in use accommodate deuterium pellets with diameters of 1.0 mm and 1.8 mm and lengths ranging from 1.5 mm to 2.7 mm which are injected radially into MST. Pellet speeds of 1300 m/s have been achieved in initial experiments, and many pellets cross the plasma diameter without completely ablating. The pellets rapidly increase the central density and peak the density profile, something not possible with gas puffing alone. Pellet injection into improved-confinement plasmas has allowed the achievement of line-averaged densities 10-20% larger than the usual limit, above which edge-resonant MHD instability is triggered, and confinement is degraded. Mechanical punches will soon be installed to allow slower pellet speeds. Work supported by U.S.D.O.E.

  1. SAF line pellet gaging. [Secure Automated Fabrication

    SciTech Connect

    Jedlovec, D.R.; Bowen W.W.; Brown, R.L.

    1983-10-01

    Automated and remotely controlled pellet inspection operations will be utilized in the Secure Automated Fabrication (SAF) line. A prototypic pellet gage was designed and tested to verify conformance to the functions and requirements for measurement of diameter, surface flaws and weight-per-unit length.

  2. [Controlled release of pseudoephedrine HCl from pellets].

    PubMed

    Vertommen, J

    1997-01-01

    This study describes the development work on a dosage form, which should release the drug pseudoephedrine HCl over twelve hours. Pellets were chosen as the dosage form. The pellets contained 20, respectively, 45 percent pseudoephedrine HCL and were produced using a high shear mixer-granulator. These pellets were coated in a fluidized bed and in a high shear mixer-granulator equipped with a microwave drying installation. The results of the experiments indicate that it is possible to produce pellets in a high shear mixer-granulator. Strong pellets with a narrow size distribution were obtained. A high shear mixer-granulator appears, therefore, to be a valuable alternative to the more commonly used pellet-forming technique of extrusion-sphere formation. The pellets could be coated as well in a fluidized bed as in a high shear mixer-granulator equipped with a microwave drying installation. A major advantage of the high shear mixer-granulator equipped with a microwave drying installation is the possibility to perform several unit operations such as mixing, pellet formation drying, and coating in one piece of equipment. With respect to the requirement of getting a release of pseudoephedrine HCl over twelve hours, the pellets containing 20 percent pseudoephedrine HCl fulfilled this requirement. For pellets containing 45 percent pseudoephedrine HCl it appears to be hard to obtain a sufficient delay in release using the commonly used coating formulations. This can be attributed to the very good solubility of pseudoephedrine HCl in water. Optimization of the coating formulation by changing the nature and concentration of the plasticizer may solve the problem. PMID:9543819

  3. 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.

  4. [Construction and function analysis of Bac operon mutants of bio-control strain Bacillus subtilis Bs-916].

    PubMed

    Luo, Chuping; Chen, Zhiyi; Liu, Yongfeng; Zhang, Jie; Liu, Youzhou; Wang, Xiaoyu; Nie, Yafeng

    2009-04-01

    Bacillus subtilis Bs-916 is an effective biocontrol agent in control rice sheath blight caused by Rhizoctonia solani. We identified and analyzed the operon Bac in Bs-916 responsible for synthesis of iturin-like lipopeptides. The research plays an important part in genetic engineered Bs-916 for further improving its bio-control activity. Taking advantage of homologous recombination method, the one mutant obtained by replacement of the Bac original promoter by a constitutive promoter P (repU) and designated BGG104; the other mutant was obtained by disruption of the Bac promoter by insertion and designated BGG105. The biological activities results showed the mutant BGG104 enhanced antagonistic activities against several pathogenic fungi and also clearly increased in hemolytic activities. However, the mutant BGG105 decreased clearly in both antagonistic activities and hemolytic activities. Crude lipopeptides were extracted with methanol from precipitates, which were obtained by adding 6 mol/L HCl to the cell-free culture broth. The results of reversed-phase high-performance liquid chromatography (HPLC) analysis of crude lipopeptides showed lipopeptides produced by Bs-916 have a different retention time compared to iturinA. The mutant BGG104 produced up to 3-fold more lipopeptides than Bs-916. However, the mutant BGG105 has not been detected countpart lipopeptides production. The molecular weights of the lipopeptides synthesized by Bac determined by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MS) were 1007.7 Da, 1021.7 Da and 1035.7 Da. They were presumed to belong to homologues differed by a structure of --CH2 and their molecular weights were not the same as the other iturin-like liopeptides', such as iturinA, mycosubtilin and bacillomycin, molecular weights. In conclusion, this paper showed the lipopeptides synthesized by Bac play crucial part in Bs-916 antifungal activities and the lipopeptides overproduction were able to enhance Bs

  5. Potential biocontrol agents for biofouling on artificial structures.

    PubMed

    Atalah, Javier; Newcombe, Emma M; Hopkins, Grant A; Forrest, Barrie M

    2014-09-01

    The accumulation of biofouling on coastal structures can lead to operational impacts and may harbour problematic organisms, including non-indigenous species. Benthic predators and grazers that can supress biofouling, and which are able to be artificially enhanced, have potential value as augmentative biocontrol agents. The ability of New Zealand native invertebrates to control biofouling on marina pontoons and wharf piles was tested. Caging experiments evaluated the ability of biocontrol to mitigate established biofouling, and to prevent fouling accumulation on defouled surfaces. On pontoons, the gastropods Haliotis iris and Cookia sulcata reduced established biofouling cover by >55% and largely prevented the accumulation of new biofouling over three months. On wharf piles C. sulcata removed 65% of biofouling biomass and reduced its cover by 73%. C. sulcata also had better retention and survival rates than other agents. Augmentative biocontrol has the potential to be an effective method to mitigate biofouling on marine structures.

  6. 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

  7. Genes from mycoparasitic fungi as a source for improving plant resistance to fungal pathogens.

    PubMed

    Lorito, M; Woo, S L; Garcia, I; Colucci, G; Harman, G E; Pintor-Toro, J A; Filippone, E; Muccifora, S; Lawrence, C B; Zoina, A; Tuzun, S; Scala, F; Fernandez, I G

    1998-07-01

    Disease resistance in transgenic plants has been improved, for the first time, by the insertion of a gene from a biocontrol fungus. The gene encoding a strongly antifungal endochitinase from the mycoparasitic fungus Trichoderma harzianum was transferred to tobacco and potato. High expression levels of the fungal gene were obtained in different plant tissues, which had no visible effect on plant growth and development. Substantial differences in endochitinase activity were detected among transformants. Selected transgenic lines were highly tolerant or completely resistant to the foliar pathogens Alternaria alternata, A. solani, Botrytis cinerea, and the soilborne pathogen Rhizoctonia solani. The high level and the broad spectrum of resistance obtained with a single chitinase gene from Trichoderma overcome the limited efficacy of transgenic expression in plants of chitinase genes from plants and bacteria. These results demonstrate a rich source of genes from biocontrol fungi that can be used to control diseases in plants.

  8. Tvbgn3, a β-1,6-Glucanase from the Biocontrol Fungus Trichoderma virens, Is Involved in Mycoparasitism and Control of Pythium ultimum▿

    PubMed Central

    Djonović, Slavica; Pozo, Maria J.; Kenerley, Charles M.

    2006-01-01

    Even though β-1,6-glucanases have been purified from several filamentous fungi, the physiological function has not been conclusively established for any species. In the present study, the role of Tvbgn3, a β-1,6-glucanase from Trichoderma virens, was examined by comparison of wild-type (WT) and transformant strains in which Tvbgn3 was disrupted (GKO) or constitutively overexpressed (GOE). Gene expression analysis revealed induction of Tvbgn3 in the presence of host fungal cell walls, indicating regulation during mycoparasitism. Indeed, while deletion or overexpression of Tvbgn3 had no evident effect on growth and development, GOE and GKO strains showed an enhanced or reduced ability, respectively, to inhibit the growth of the plant pathogen Pythium ultimum compared to results with the WT. The relevance of this activity in the biocontrol ability of T. virens was confirmed in plant bioassays. Deletion of the gene resulted in levels of disease protection that were significantly reduced from WT levels, while GOE strains showed a significantly increased biocontrol capability. These results demonstrate the involvement of β-1,6-glucanase in mycoparasitism and its relevance in the biocontrol activity of T. virens, opening a new avenue for biotechnological applications. PMID:16997978

  9. 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.

  10. 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. PMID:22222837

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  12. Improved biocontrol of fruit decay fungi with Pichia pastoris recombinant strains expressing Psd1 antifungal peptide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Future expansion of biological control of postharvest diseases will largely depend on improving its effectiveness under an increased range of conditions and expanding the spectrum of activity to new commodities and new diseases. Plasmid pGAPZaC/Psd1, a binary vector containing the cDNA encoding seq...

  13. 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.

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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. PMID:26026881

  19. 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.

  20. Identification of volatiles produced by Cladosporium cladosporioides CL-1, a fungal biocontrol agent that promotes plant growth.

    PubMed

    Paul, Diby; Park, Kyung Seok

    2013-10-16

    Certain microbial Volatile Organic Compounds (VOCs) have been reported to enhance the growth and development of plants. The biocontrol fungi, Cladosporium cladosporioides CL-1 significantly improved the growth of tobacco seedlings in vitro when they were co-cultivated without physical contact. SPME Quadrupole GC/MS/MS revealed that CL-1 emited the volatiles α-pinene, (-)-trans-caryophyllene, tetrahydro-2,2,5,5-tetramethylfuran, dehydroaromadendrene, and (+)-sativene. Potential roles of these volatiles in plant growth and development are discussed. Even though there were several fungal VOCs reported in the past that could influence plant growth, their exact mechanisms of action are not fully known. Fungal VOC-mediated plant growth promotion requires in-depth study in order for this technology to be used in large scale for crops, especially those grown under greenhouse conditions.

  1. 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. PMID:26466874

  2. 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. PMID:26725152

  3. 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.

  4. 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.

  5. 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. PMID:26214840

  6. 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).

  7. 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

  8. Population structure of Aspergillus flavus before and after biocontrol treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aspergillus flavus is a fungal pathogen of many important crops worldwide. We sampled A. flavus strains from a cornfield in Rocky Mount, North Carolina, over a period of two years. Plots were inoculated at tasselling with either AF36 or NRRL 21882 (=Afla-Guard) biocontrol strains, both of which are ...

  9. Challenges and opportunities for the commercialization of postharvest biocontrol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  10. 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.

  11. 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.

  12. Comment on Li pellet Conditioning in TFTR

    SciTech Connect

    R.V. Budny

    2011-05-23

    Li pellet conditioning in TFTR results in a reduction of the edge electron density which allows increased neutral beam penetration, central heating, and fueling. Consequently the temperature profiles became more peaked with higher central Ti, Te, and neutron emission rates.

  13. 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.

  14. 21 CFR 520.1628 - Oxfendazole powder and pellets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Oxfendazole powder and pellets. 520.1628 Section... Oxfendazole powder and pellets. (a) Specifications—(1) Powder for suspension. Each gram of powder contains 7.57 percent oxfendazole. (2) Pellets. Each gram of pellets contains 6.49 percent oxfendazole....

  15. 21 CFR 520.1628 - Oxfendazole powder and pellets.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Oxfendazole powder and pellets. 520.1628 Section... Oxfendazole powder and pellets. (a) Specifications—(1) Powder for suspension. Each gram of powder contains 7.57 percent oxfendazole. (2) Pellets. Each gram of pellets contains 6.49 percent oxfendazole....

  16. 21 CFR 520.1628 - Oxfendazole powder and pellets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Oxfendazole powder and pellets. 520.1628 Section... Oxfendazole powder and pellets. (a) Specifications—(1) Powder for suspension. Each gram of powder contains 7.57 percent oxfendazole. (2) Pellets. Each gram of pellets contains 6.49 percent oxfendazole....

  17. 21 CFR 520.1628 - Oxfendazole powder and pellets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Oxfendazole powder and pellets. 520.1628 Section... Oxfendazole powder and pellets. (a) Specifications—(1) Powder for suspension. Each gram of powder contains 7.57 percent oxfendazole. (2) Pellets. Each gram of pellets contains 6.49 percent oxfendazole....

  18. 21 CFR 520.1628 - Oxfendazole powder and pellets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxfendazole powder and pellets. 520.1628 Section... Oxfendazole powder and pellets. (a) Specifications—(1) Powder for suspension. Each gram of powder contains 7.57 percent oxfendazole. (2) Pellets. Each gram of pellets contains 6.49 percent oxfendazole....

  19. 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.

  20. Pellet-press-to-sintering-boat nuclear fuel pellet loading system

    SciTech Connect

    Bucher, G.D.

    1988-08-23

    This patent describes a system for loading nuclear fuel pellets into a sintering boat from a pellet press which ejects newly made the pellets from a pellet press die table surface. The system consists of: (a) a bowl having an inner surface, a longitudinal axis, an open and generally circular top of larger diameter, and an open and generally circular bottom of smaller diameter; (b) means for supporting the bowl in a generally upright position such that the bowl is rotatable about its longitudinal axis; (c) means for receiving the ejected pellets proximate the die table surface of the pellet press and for discharging the received pellets into the bowl at a location proximate the inner surface towards the top of the bowl with a pellet velocity having a horizontal component which is generally tangent to the inner surface of the bowl proximate the location; (d) means for rotating the bowl about the longitudinal axis such that the bowl proximate the location has a velocity generally equal, in magnitude and direction, to the horizontal component of the pellet velocity at the location; and (e) means for moving the sintering boat generally horizontally beneath and proximate the bottom of the bowl.

  1. In vitro and in vivo evaluation of floating riboflavin pellets developed using the melt pelletization process.

    PubMed

    Hamdani, J; Goole, J; Moës, A J; Amighi, K

    2006-10-12

    Floating pellets were prepared using the melt pelletization process in a Mi-Pro high shear mixer (Pro-C-epT, Belgium). Formulations were based on a mixture of Compritol and Precirol as meltable binders and on the use of sodium bicarbonate and tartaric acid as gas-generating agents. Good floating abilities were obtained by using the gas-generating agents in both the inner matrix and the outer coating layer of the pellets. In vitro evaluation of floating capability was performed both by using the resultant weight apparatus and by counting floating pellets at the surface of beakers containing 0.1N HCl solution, in vivo evaluation of floating pellets capabilities was also performed. Riboflavin-containing floating pellets (FRF) were administered orally to nine healthy volunteers versus non-floating pellets (NFRF). Volunteers were divided in two groups, fasted group (n=4) 729 kcal and fed group (n=5) 1634 kcal as the total calorie intake on the testing day. An increase of urinary excretion of riboflavin was observed when the volunteers were dosed with the floating pellets, especially after feeding. As riboflavin has a narrow window of absorption in the upper part of small intestine, this phenomenon could be attributable to the gastric retention of floating pellets. PMID:16815656

  2. 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.

  3. 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

  4. 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.

  5. Antibiotic release from impregnated pellets and beads.

    PubMed

    Bowyer, G W; Cumberland, N

    1994-03-01

    Antibiotic impregnated beads are being used increasingly in the initial treatment of open fracture wounds, producing high antibiotic levels locally, over the first few days. Pellets were prepared to assess the release of the following antibiotics: benzylpenicillin, flucloxacillin, amoxycillin, amoxycillin-clavulanate (Co-Amoxiclav), ciprofloxacin, imipenem, or gentamicin; the carrier material was either polymethylmethacrylate (PMMA) or plaster of Paris (PoP). Elution of antibiotic over 72 hours from the pellets in vitro was determined using an agar-diffusion microbiologic assay. The initial rapid release of antibiotic lasted 12-24 hours, with release from PoP pellets at least four-fold greater than that from corresponding PMMA pellets. A second phase consisted of a sustained but gradually diminishing elution. The release of antibiotics from PoP pellets compared favorably with that from the PMMA beads currently used. We conclude that PoP pellets may be particularly suitable for short-term applications such as infection prophylaxis in open fractures.

  6. Tritium proof-of-principle pellet injector

    SciTech Connect

    Fisher, P.W.

    1991-07-01

    The tritium proof-of-principle (TPOP) experiment was designed and built by Oak Ridge National Laboratory (ORNL) to demonstrate the formation and acceleration of the world's first tritium pellets for fueling of future fusion reactors. The experiment was first used to produce hydrogen and deuterium pellets at ORNL. It was then moved to the Tritium Systems Test Assembly at Los Alamos National Laboratory for the production of tritium pellets. The injector used in situ condensation to produce cylindrical pellets in a 1-m-long, 4-mm-ID barrel. A cryogenic {sup 3}He separator, which was an integral part of the gun assembly, was capable of lowering {sup 3}He levels in the feed gas to <0.005%. The experiment was housed to a glovebox for tritium containment. Nearly 1500 pellets were produced during the course of the experiment, and about a third of these were pure tritium or mixtures of deuterium and tritium. Over 100 kCi of tritium was processed through the experiment without incident. Tritium pellet velocities of 1400 m/s were achieved with high-pressure hydrogen propellant. The design, operation, and results of this experiment are summarized. 34 refs., 44 figs., 3 tabs.

  7. Tritium proof-of-principle pellet injector

    NASA Astrophysics Data System (ADS)

    Fisher, P. W.

    1991-07-01

    The tritium proof-of-principle (TPOP) experiment was designed and built by Oak Ridge National Laboratory (ORNL) to demonstrate the formation and acceleration of the world's first tritium pellets for fueling of future fusion reactors. The experiment was first used to produce hydrogen and deuterium pellets at ORNL. It was then moved to the Tritium Systems Test Assembly at Los Alamos National Laboratory for the production of tritium pellets. The injector used in situ condensation to produce cylindrical pellets in a 1-m-long, 4-mm-ID barrel. A cryogenic He-3 separator, which was an integral part of the gun assembly, was capable of lowering He-3 levels in the feed gas to less than 0.005 percent. The experiment was housed to a glovebox for tritium containment. Nearly 1500 pellets were produced during the course of the experiment, and about a third of these were pure tritium or mixtures of deuterium and tritium. Over 100 kCi of tritium was processed through the experiment without incident. Tritium pellet velocities of 1400 m/s were achieved with high-pressure hydrogen propellant. The design, operation, and results of this experiment are summarized.

  8. Gas adsorption capacity of wood pellets

    DOE PAGESBeta

    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 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

  9. Experiments with the Ignitor Pellet Injector (IPI)

    NASA Astrophysics Data System (ADS)

    Frattolillo, A.; Migliori, S.; Podda, S.; Bombarda, F.; Baylor, L. R.; Caughman, J. B. O.; Combs, S. K.; Foust, C.; Fehling, D.; McJill, J. M.; Meitner, S.; Roveta, G.

    2009-11-01

    The four barrel, two-stage pneumatic injector for the Ignitor experiment (IPI), built by ENEA and ORNL, has been tested in the course of three esperimental campaigns. The optimal shaping of the propellant pressure pulse to improve pellet acceleration is provided by specially designed Pulse Shaping Valves. These have been modified and tested on a new facility that allows operating pellet injector components in conditions close to those at which they will have to operate on the IPI. Fast closing (< 10 ms) valves drastically reduce the expansion volumes needed to remove the propellant gas at the end of the guiding tube. The four barrel (2.1, 2.2, 3.0 and 4.6 mm bores) pipe-gun cryostat is cooled down by a closed cycle refrigerator, and pellet diagnostics for measuring speed and mass of the pellets, as well as for capturing in-flight pictures of all four pellets were developed for this application. The final impact target is equipped with a shock accelerometer. The injector is designed to deliver pellets with velocities up to 4 km/s (2 km/s already achieved): the results of the latest experimental campaign will be reported.

  10. Adaptive immunity to fungi.

    PubMed

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

    2014-11-06

    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.

  11. Adaptive immunity to fungi.

    PubMed

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

    2012-01-01

    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.

  12. A new, pellet-forming fungal strain: its isolation, molecular identification, and performance for simultaneous sludge-solids reduction, flocculation, and dewatering.

    PubMed

    Subramanian, S Bala; Yan, Song; Tyagi, R D; Surampalli, R Y

    2008-09-01

    Filamentous and nonfilamentous microorganisms can cause bulking and foaming in wastewater sludge settling and dewatering. In this research, sludge degradation and bioflocculation was studied using pellet-forming filamentous fungi isolated from municipal wastewater sludge. To understand the role of filamentous fungi in sludge settling and dewatering, the isolated fungi was inoculated with both spores and pellets (beads) into sterilized and nonsterilized sludge having different suspended-solids concentrations. Biofloc formation, sludge settling, sludge degradation, change in pH of fungal-grown medium, zeta potential, and microscopic analysis of bioflocs were performed. The suspended-solids concentration was found to decrease over 5 d of incubation because of use and biodegradation by fungal biomass. The isolated fungal strain was well adapted to forming biofloc and to interacting with natural microbial flora and exhibited low capillary-suction time for sludge dewatering. PMID:18939607

  13. Invert emulsion: Method of preparation and application as proper formulation of entomopathogenic fungi

    PubMed Central

    Batta, Yacoub A.

    2016-01-01

    The present article describes the technique used for preparing the invert emulsion (water-in-oil type) then, selecting the most proper formulation of invert emulsion for being used as a carrier formulation of entomopathogenic fungi. It also describes the method used for testing the efficacy of the formulated fungi as biocontrol agents of targeted insects. Detailed examples demonstrating the efficacy of formulated strains of entomopathogenic fungi against certain species of insect pests were included in the present article. The techniques and methods described in this article are reproducible and helpful in enhancing the effectiveness of formulated fungi against wide range of targeted insects in comparison with the unformulated form of these fungi. Also, these techniques and methods can be used effectively in crop protection and in the integrated pest management programs. Finally, it is important to indicate that the ingredients used for preparation of the invert emulsion have no environmental side-effects or health risks since these ingredients are safe to use and can be used in manufacturing of cosmetics or as food additives.•Description of method used for preparation of invert emulsion (water-in-oil type) and selecting the most stable and non-viscous emulsion.•Description of technique used for introducing the entomopathogenic fungi into the selected stable and non-viscous invert emulsion.•Description of method for testing the efficacy of introduced entomopathogenic fungus into the selected invert emulsion against targeted insects with detailed examples on the efficacy testing. PMID:26981435

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. The toolbox of Trichoderma spp. in the biocontrol of Botrytis cinerea disease.

    PubMed

    Vos, Christine M F; De Cremer, Kaat; Cammue, Bruno P A; De Coninck, Barbara

    2015-05-01

    Botrytis cinerea is a necrotrophic fungal pathogen causing disease in many plant species, leading to economically important crop losses. So far, fungicides have been widely used to control this pathogen. However, in addition to their detrimental effects on the environment and potential risks for human health, increasing fungicide resistance has been observed in the B. cinerea population. Biological control, that is the application of microbial organisms to reduce disease, has gained importance as an alternative or complementary approach to fungicides. In this respect, the genus Trichoderma constitutes a promising pool of organisms with potential for B. cinerea control. In the first part of this article, we review the specific mechanisms involved in the direct interaction between the two fungi, including mycoparasitism, the production of antimicrobial compounds and enzymes (collectively called antagonism), and competition for nutrients and space. In addition, biocontrol has also been observed when Trichoderma is physically separated from the pathogen, thus implying an indirect systemic plant defence response. Therefore, in the second part, we describe the consecutive steps leading to induced systemic resistance (ISR), starting with the initial Trichoderma-plant interaction and followed by the activation of downstream signal transduction pathways and, ultimately, the defence response resulting in ISR (ISR-prime phase). Finally, we discuss the ISR-boost phase, representing the effect of ISR priming by Trichoderma spp. on plant responses after additional challenge with B. cinerea.

  20. 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.

  1. 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

  2. Three small RNAs jointly ensure secondary metabolism and biocontrol in Pseudomonas fluorescens CHA0.

    PubMed

    Kay, Elisabeth; Dubuis, Christophe; Haas, Dieter

    2005-11-22

    In many Gram-negative bacteria, the GacS/GacA two-component system positively controls the expression of extracellular products or storage compounds. In the plant-beneficial rhizosphere bacterium Pseudomonas fluorescens CHA0, the GacS/GacA system is essential for the production of antibiotic compounds and hence for biological control of root-pathogenic fungi. The small (119-nt) RNA RsmX discovered in this study, together with RsmY and RsmZ, forms a triad of GacA-dependent small RNAs, which sequester the RNA-binding proteins RsmA and RsmE and thereby antagonize translational repression exerted by these proteins in strain CHA0. This small RNA triad was found to be both necessary and sufficient for posttranscriptional derepression of biocontrol factors and for protection of cucumber from Pythium ultimum. The same three small RNAs also positively regulated swarming motility and the synthesis of a quorum-sensing signal, which is unrelated to N-acyl-homoserine lactones, and which autoinduces the Gac/Rsm cascade. Expression of RsmX and RsmY increased in parallel throughout cell growth, whereas RsmZ was produced during the late growth phase. This differential expression is assumed to facilitate fine tuning of GacS/A-controlled cell population density-dependent regulation in P. fluorescens.

  3. An investigation into pellet dispersion ballistics.

    PubMed

    Nag, N K; Sinha, P

    1992-08-01

    Existing works on pellet dispersion ballistics are confined to some data-based models derived from statistical analysis of observed patterns on targets but the underlying process causing the dispersion lacks due attention. The present article delves into the relatively unexplored areas of dispersion phenomena, and attempts to develop a theoretical model for general application. The radial velocity distribution of pellets has been worked out by probing into the physical process of dispersion based on transfer of momentum from undispersed shot mass to dispersed pellets. The ratio 2u/v0 (u = root mean square (r.m.s.) radial velocity and v0 = muzzle velocity of the pellets) is found to be fairly constant for a fixed gun-ammunition combination and has been suitably designated as 'Dispersion Index' (DI) characterising its dispersion capability. The present model adequately accounts for pellet distribution on targets and it appears that 'Effective Shot Dispersion' (ESD) as introduced by Mattoo and Nabar [ESD = [(4/N0)sigma Ri2]1/2, where N(0) is the total number of pellets and Ri is the radial distance of the i-th pellet from centre of pattern], gives a faithful numerical measure of overall dispersion at a given distance. A relationship between ESD and firing distance, incorporating the effects of air resistance and gravity has been worked out, which reveals that DI controls the dispersion at a given distance. For small distances (less than 20 m) the relation reduces to a linear one, as already observed empirically and looks like ESD = E0+DI x firing distance, E0 being a parameter dependent on gun and ammunition. The present model, unlike earlier ones, is versatile enough to explain the natures of the dependence of dispersion on firing distance as well as on gun-ammunition parameters, which are essential for a faithful reconstruction of a crime scene. The model has been tested with such experimental data as are available and reasonable agreement is observed. PMID:1398370

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Enhanced enzyme production with the pelleted form of D. squalens in laboratory bioreactors using added natural lignin inducer.

    PubMed

    Babič, Janja; Pavko, Aleksander

    2012-03-01

    White-rot fungi are extensively used in various submerged biotechnology processes to produce ligninolytic enzymes. Transfer of the process from the laboratory to the industrial level requires optimization of the cultivation conditions on the laboratory scale. An interesting area of optimization is pellet growth since this morphological form solves problems such as the decreased oxygen concentration, limited heat, and nutrient transport, which usually occur in dispersed mycelium cultures. Many submerged fermentations with basidiomycetes in pellet form were done with Phanerochaete, Trametes, and Bjerkandera species, among others. In our study, another promising basidiomycete, D. squalens, was used for ligninolytic enzyme production. With the addition of wood particles (sawdust) as a natural inducer and optimization of mixing and aeration conditions in laboratory stirred tank (STR) and bubble column (BCR) reactors on pellet growth and morphology, the secretion of laccase and the manganese-dependent peroxidase into the medium was substantially enhanced. The maximum mean pellet radius was achieved after 10 days in the BCR (5.1 mm) where pellets were fluffy and 5 days in the STR (3.5 mm) where they were round and smooth. The maximum Lac activity (1,882 U l(-1)) was obtained after 12 days in the STR, while maximum MnP activity (449.8 U l(-1)) occurred after 18 days in the BCR. The pellet size and morphology depended on the agitation and aeration conditions and consequently influenced a particular enzyme synthesis. The enzyme activities were high and comparable with the activities found for other investigations in reactors with basidiomycetes in the form of pellets. PMID:21922328

  9. 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. PMID:19121038

  10. 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. PMID:12702290

  11. Phages of Listeria offer novel tools for diagnostics and biocontrol

    PubMed Central

    Hagens, Steven; Loessner, Martin J.

    2014-01-01

    Historically, bacteriophages infecting their hosts have perhaps been best known and even notorious for being a nuisance in dairy-fermentation processes. However, with the rapid progress in molecular microbiology and microbial ecology, a new dawn has risen for phages. This review will provide an overview on possible uses and applications of Listeria phages, including phage-typing, reporter phage for bacterial diagnostics, and use of phage as biocontrol agents for food safety. The use of phage-encoded enzymes such as endolysins for the detection and as antimicrobial agent will also be addressed. Desirable properties of candidate phages for biocontrol will be discussed. While emphasizing the enormous future potential for applications, we will also consider some of the intrinsic limitations dictated by both phage and bacterial ecology. PMID:24782847

  12. 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

  13. Exploring antagonistic metabolites of established biocontrol agent of marine origin.

    PubMed

    Rane, Makarand Ramesh; Sarode, Prashant Diwakar; Chaudhari, Bhushan Liladhar; Chincholkar, Sudhir Bhaskarrao

    2008-12-01

    Biocontrol ability of Pseudomonas aeruginosa ID 4365, a biocontrol agent of groundnut phytopathogens from marine origin, was previously attributed to the production of pyoverdin type of siderophores. However, pyoverdin-rich supernatants of this organism showed better antifungal activity compared to equivalent amount of purified pyoverdin indicating presence of undetected metabolite(s) in pyoverdin rich supernatants. On the basis of observation that antagonistic activity was iron-dependent and iron-independent, an attempt was made to detect the presence of additional metabolites. In addition to pyoverdin, strain produced additional siderophores, viz. pyochelin and salicylic acid. Two broad spectrum antifungal compounds, viz. pyocyanin and phenazine-1-carboxylic acid, were detected, characterized, and activity against phytopathogens was demonstrated. Iron- and phosphate-dependent co-production of siderophores and phenazines was confirmed. Strain showed additional features like production of hydrogen cyanide, indol-3-acetic acid, and phosphate solubilization. PMID:18626581

  14. Air gun pellet: cardiac penetration and peripheral embolization.

    PubMed

    Işık, Onur; Engin, Çağatay; Daylan, Ahmet; Şahutoğlu, Cengiz

    2016-05-01

    Use of high-velocity air guns can to lead to serious injuries. Management options of cardiac pellet gun injuries are based on patient stability, and course and location of the pellet. Presently reported is the case of a boy who was shot with an air gun pellet. Following right ventricular entry, the pellet lodged in the left atrium and embolized to the right iliac and femoral artery. Following pellet localization, right ventricular injury was repaired, and the pellet was removed successfully. PMID:27598599

  15. Genome Sequence of the Biocontrol Strain Pseudomonas fluorescens F113

    PubMed Central

    Redondo-Nieto, Miguel; Barret, Matthieu; Morrisey, John P.; Germaine, Kieran; Martínez-Granero, Francisco; Barahona, Emma; Navazo, Ana; Sánchez-Contreras, María; Moynihan, Jennifer A.; Giddens, Stephen R.; Coppoolse, Eric R.; Muriel, Candela; Stiekema, Willem J.; Rainey, Paul B.; Dowling, David; O'Gara, Fergal; Martín, Marta

    2012-01-01

    Pseudomonas fluorescens F113 is a plant growth-promoting rhizobacterium (PGPR) that has biocontrol activity against fungal plant pathogens and is a model for rhizosphere colonization. Here, we present its complete genome sequence, which shows that besides a core genome very similar to those of other strains sequenced within this species, F113 possesses a wide array of genes encoding specialized functions for thriving in the rhizosphere and interacting with eukaryotic organisms. PMID:22328765

  16. 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.

  17. 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

  18. 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

  19. 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

  20. 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

  1. Responses of yeast biocontrol agents to environmental stress.

    PubMed

    Sui, Yuan; Wisniewski, Michael; Droby, Samir; Liu, Jia

    2015-05-01

    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.

  2. 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

  3. Development and optimization of solid dispersion containing pellets of itraconazole prepared by high shear pelletization.

    PubMed

    Ye, Guanhao; Wang, Siling; Heng, Paul Wan Sia; Chen, Ling; Wang, Chao

    2007-06-01

    This study investigated the solid dispersion containing pellets of itraconazole for enhanced drug dissolution rate. The influence of process parameters used during high shear pelletization on the pellet properties including pellet size and dissolution rate was also studied. Solid dispersions of itraconazole were prepared with Eudragit E100, a hydrophilic polymer, by a simple fusion method followed by powdered and characterized by differential scanning calorimetry and X-ray powder diffraction. Solid dispersions containing pellets were consequently prepared using a lab-scale high shear mixer. In order to improve the product quality, a central composite design was applied to optimize the critical process variables, such as impeller speed and kneading time, and the results were modeled statistically. Itraconazole was presented as an amorphous state in the solid dispersion prepared at a drug to polymer ratio of 1:2. Both studied parameters had great effect on the responses. Powdered solid dispersion and pellets prepared using the optimal parameter settings showed approximately 30- and 70-fold increases in dissolution rate over the pure drug, respectively. Solid dispersion prepared by simple fusion method could be an option for itraconazole solubility enhancement. Pelletization process in high shear mixer can be optimized effectively by central composite design. PMID:17241757

  4. 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.

  5. 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.

  6. Studies of cell pellets: I. Electrical properties and porosity.

    PubMed Central

    Abidor, I G; Li, L H; Hui, S W

    1994-01-01

    Cell pellets formed by centrifugation provided a good system to study the osmotic behavior, electroporation, and interaction between cells. Rabbit erythrocyte pellets were used in this study because they were simpler than nucleated cells to model analytically. Structurally, cell pellets possessed properties of porous solid bodies and gels. Electrically, cell pellets were shown to behave as a parallel set of resistance, Rp, and capacitance, Cp. Information on pellet structures was obtained from electric measurements. The pellet resistance reflected the intercellular conductivity (porosity and gap conductivity), whereas the pellet capacitance depended mostly on membrane capacitance. The pellet resistance was more sensitive to experimental conditions. The intercellular gap distance can be derived from pellet porosity measurements, providing the cell volume and surface area were known. Rp increased and relaxed exponentially with time when centrifugation started and stopped; the cycles were reversible. When supernatants were exchanged with solutions containing hypotonic electrolytes or macromolecules (such as PEG) after the pellets were formed, complicated responses to different colloidal osmotic effects were observed. A transient decrease followed by a large increase of Rp was observed after the application of a porating electric pulse, as expected from a momentary membrane breakdown, followed by a limited colloidal-osmotic swelling of pelleted cells. The equilibrium values of Rp, Cp, pellet porosity, and intercellular distances were measured and calculated as functions of cell number, centrifugation force, and ionic strength of the exchanged supernatant. Thus, the structure and properties of cell pellets can be completely characterized by electrical measurements. Images FIGURE 1 FIGURE 11 PMID:7919015

  7. 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)

  8. [Fungi at the beach].

    PubMed

    Szepetiuk, G; Piérard-Franchimont, C; Piérard, G E

    2010-01-01

    Fungi responsible for dermatomycoses survive in a resting phase inside diverse parts of the environment. Sand in the wet, partly wet and dry portions of the beaches frequently contains dermatophytes, yeasts and moulds. These microorganisms possibly infect skin and nails during summertime.

  9. 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.

  10. Characterization of biodegradable poly-3-hydroxybutyrate films and pellets loaded with the fungicide tebuconazole.

    PubMed

    Volova, Tatiana; Zhila, Natalia; Vinogradova, Olga; Shumilova, Anna; Prudnikova, Svetlana; Shishatskaya, Ekaterina

    2016-03-01

    Biodegradable polymer poly(3-hydroxybutyrate) (P3HB) has been used as a matrix to construct slow-release formulations of the fungicide tebuconazole (TEB). P3HB/TEB systems constructed as films and pellets have been studied using differential scanning calorimetry, X-ray structure analysis, and Fourier transform infrared spectroscopy. TEB release from the experimental formulations has been studied in aqueous and soil laboratory systems. In the soil with known composition of microbial community, polymer was degraded, and TEB release after 35 days reached 60 and 36 % from films and pellets, respectively. That was 1.23 and 1.8 times more than the amount released to the water after 60 days in a sterile aqueous system. Incubation of P3HB/TEB films and pellets in the soil stimulated development of P3HB-degrading microorganisms of the genera Pseudomonas, Stenotrophomonas, Variovorax, and Streptomyces. Experiments with phytopathogenic fungi F. moniliforme and F. solani showed that the experimental P3HB/TEB formulations had antifungal activity comparable with that of free TEB. PMID:26561327

  11. The Fast Pellet Injector Program for Ignitor

    NASA Astrophysics Data System (ADS)

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

    2003-10-01

    The characteristics of a fast pellet injector for the Ignitor ignition experiment have been identified. In order to produce sufficiently peaked density profiles during the initial phase of the current ramp and to sustain them along the flat top phase, a multiple injector capable of shooting pellets of variable sizes will be developed. The program involves the collaboration of the ENEA Laboratory at Frascati and the Fusion Technology Group of Oak Ridge. The initial activities will be devoted to the development of a 4 barrel, double stage gun able to reach speeds up to 4 km/s. The compact size of the Ignitor machine makes injection from the high field side unpractical, while it is unclear that a vertical injection close to the magnetic axis will be beneficial. Simulations performed with the PELLET code(W.A. Houlberg, et al., Nuclear Fusion) 28, 595 (1988), on the other hand, indicate that pellet speeds of 3-4 km/s would allow a sufficient particle penetration from the low field side, particularly during the initial current ramp up phase, when the plasma temperature is still relatively low and good control of the density profile is most desirable.

  12. Performance of the Ignitor Pellet Injector

    NASA Astrophysics Data System (ADS)

    Frattolillo, A.; Migliori, S.; Podda, S.; Bombarda, F.; Baylor, L. R.; Caughman, J. B. O.; Combs, S. K.; Foust, C.; Fehling, D.; McJill, J. M.; Meitner, S.; Roveta, G.

    2008-11-01

    ENEA and ORNL have built a four barrel, two-stage pneumatic injector for the Ignitor experiment featuring two innovative concepts: (i) an optimal shaping of the propellant pressure pulse to improve pellet acceleration, and (ii) the use of fast closing (< 10 ms) valves to drastically reduce the expansion volumes of the propellant gas removal system. The injector is designed to deliver pellets of different sizes with velocities up to 4 km/s, capable of penetrating near the center of the plasma column when injected from the low field side in Ignitor burning plasmas (n010^21 m-3, T011 keV). The ENEA sub-system, which includes the two-stage guns and pulse-shaping valves, the gas removal system, with associated controls and diagnostics, and the ORNL sub-system, consisting of the cryostat and pellet diagnostics, with related control and data acquisition system, have been assembled in Oak Ridge. Pellet speeds of 2 km/s have been achieved, despite the unfavorable configuration adopted in order to carry out some preliminary tests immediately after assembling the system, a very promising result. A second experimental campaign is planned for the 2008 Fall, when all four diagnostic channels should be complete.

  13. New Results with the Ignitor Pellet Injector

    NASA Astrophysics Data System (ADS)

    Frattolillo, A.; Migliori, S.; Podda, S.; Bombarda, F.; Baylor, L. R.; Combs, S. K.; Foust, C. R.; Meitner, S.; Fehling, D.; Roveta, G.

    2011-10-01

    The Ignitor Pellet Injector (IPI) has been developed in collaboration between ENEA and ORNL to provide greater control over the density time evolution and the density peaking in plasmas produced by the Ignitor device. The four barrel, two stage injector has been designed to reach speeds up to 4 km/s, for effective low field side injection into ignited plasmas (Te ≅Ti ≅ 11 keV). The present arrangement accomodates both a two-stage gun and a standard propellant valve on each barrel, allowing seamless switching between standard and high speed operation on any or all gun barrels. The cryostat is actively cooled by a pulse tube refrigerator, equipped with supplemental cooling from a liquid He dewar. The injector has shown very good repeatability; however, intact pellets were not observed over 2 km/s, possibly due to a spinning effect on the pellets at higher speed. The cross sections of the guiding tubes have been increased and other design improvements have been implemented, aimed in particular at reducing leak rates and reducing the dispersion of the pellet trajectories, in preparation of the experimental campaign reported here. Sponsored in part by ENEA of Italy, and by the U.S. D.O.E.

  14. Ceramic fuel pellets for isotopic heat sources

    SciTech Connect

    Rankin, D.T.; Congdon, J.W.; Livingston, J.T.; Duncan, N.D.

    1980-01-01

    The General-Purpose Heat Source (GPHS) will supply power for future space missions. The GPHS fuel pellets are fabricated by hot pressing a blended mixture of /sup 238/PuO/sub 2/ granules prepared from calcined plutonium oxalate. Results of a test program which led to the development of the production process are described.

  15. Paleoparasitological analysis of a raptor pellet from southern Patagonia.

    PubMed

    Fugassa, M H; Sardella, N H; Denegri, G M

    2007-04-01

    Organic remains attributable to one regurgitated pellet were examined. The pellet, belonging to a bird of prey and collected from a cave of Southern Patagonia, was dated at 6,540 +/- 110 yr. With standard paleoparasitological procedures, eggs of Capillaria sp. and a mite, Demodex sp., were found. The parasites found in the pellet belong to a rodent ingested by the bird. The present report constitutes the first paleoparasitological study of a regurgitated pellet. PMID:17539429

  16. Paleoparasitological analysis of a raptor pellet from southern Patagonia.

    PubMed

    Fugassa, M H; Sardella, N H; Denegri, G M

    2007-04-01

    Organic remains attributable to one regurgitated pellet were examined. The pellet, belonging to a bird of prey and collected from a cave of Southern Patagonia, was dated at 6,540 +/- 110 yr. With standard paleoparasitological procedures, eggs of Capillaria sp. and a mite, Demodex sp., were found. The parasites found in the pellet belong to a rodent ingested by the bird. The present report constitutes the first paleoparasitological study of a regurgitated pellet.

  17. Particle confinement of pellet-fuelled tokamak plasma

    NASA Astrophysics Data System (ADS)

    Valovič, M.; Axon, K.; Garzotti, L.; Saarelma, S.; Thyagaraja, A.; Akers, R.; Gurl, C.; Kirk, A.; Lloyd, B.; Maddison, G. P.; Morris, A. W.; Patel, A.; Shibaev, S.; Scannell, R.; Taylor, D.; Walsh, M.; MAST Team

    2008-07-01

    This paper quantifies the particle confinement of pellet-fuelled plasmas as measured in the Mega Ampere Spherical Tokamak. The dataset is restricted mostly to neutral beam heated plasmas in H-mode and to shallow pellets launched from the high-field side. It is shown that the pellet deposition can be explained only by invoking the ∇B drift of the pellet ablatant. The pellet creates a zone with positive density gradient and increased temperature gradient. Simulations show that these changes could increase the level of micro-turbulence and thus enhance further the penetration of pellet-deposited particles towards the core. Post-pellet dynamics of the density profile is characterized by the pellet retention time τpel. It is shown that τpel correlates with the status of the edge transport barrier (L-mode or H-mode) and decreases rapidly for pellet deposition radius rpel approaching the plasma edge. For ELMy H-mode and pellet deposition radius of rpel ≈ 0.8a, the pellet retention time is about 20% of the energy confinement time. The fuelling requirement by the pellets for ITER and the Component Test Facility based on the spherical tokamak is discussed.

  18. 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)

  19. The relationship of biofilm production to biocontrol activity of Burkholderia pyrrocinia FP62

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foliar biocontrol agent (BCA) efficacy is often inconsistent due to poor colonization and survival on plant surfaces. Burkholderia pyrrocinia FP62, a superior leaf colonist and BCA of Botrytis cinerea, forms unsaturated biofilms on plant surfaces. To determine the relationship between biocontrol act...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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....

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. Tabletting behaviour of pellets of a series of porosities--a comparisonbetween pellets of two different compositions.

    PubMed

    Nicklasson, F; Johansson, B; Alderborn, G

    1999-04-01

    The tabletting behaviour of pellets prepared from a 4:1 mixture of dicalcium phosphate dihydrate (DCP) and microcrystalline cellulose (MCC) was studied and compared with the tabletting behaviour of pellets made solely from microcrystalline cellulose (results from an earlier study by Johansson et al.). A series of pellets with porosities in the range 26-55% were prepared and tabletted at applied pressures of 25-200 MPa. Tablets were also formed from lubricated pellets. The degree of compression during compaction was calculated, and the porosity and tensile strength of the tablets and their permeability to air flow were determined. The porosity of the pellets was found to significantly affect the tabletting behaviour of the DCP/MCC pellets. However, the relationship between pellet porosity and tablet data for the DCP/MCC pellets was different from that for the MCC pellets. The DCP/MCC pellets were generally less prone to a reduction in volume during tabletting, and the pore structure of the DCP/MCC tablets was more closed. It was concluded that the DCP/MCC pellets were more rigid and underwent a different mode of deformation during tabletting than the MCC pellets. This mode of deformation was characterised by a more limited bulk deformation and a more extensive surface deformation at the pellet surfaces. The DCP/MCC pellets tended to give tablets of a lower mechanical strength. They were also less sensitive to lubrication in terms of their compactability, which may be explained either by less surface coverage by the lubricant before compression or rupture of the lubricant film during compression caused by the more extensive surface deformation of DCP/MCC pellets.

  7. 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.

  8. Pilot plant processing of sodium bifluoride to sodium fluoride pellets

    SciTech Connect

    Leone, S.M.

    1985-01-25

    Sodium fluoride (NaF) traps in the PGDP purge cascade presently use NaF pellets to remove residual UF{sub 6} from the gas stream. These pellets are procured from ORGDP which converts sodium bifluoride pellets to NaF by thermal decomposition. Discussions of the possibility of no longer producing pellets at ORGDP, due to oven corrosion problems, led to a pilot plant test at PGDP. This test was designed to examine the feasibility of producing the NaF pellets at PGDP in the event that an alternative source of supply became necessary. Satisfactory pellets were produced without difficulty; however, it was determined that the conversion process could not be readily carried out in the existing NaF traps. Construction of a separate facility with provisions to handle the large quantities of hydrogen fluoride (HF) released during the process would be required to produce pellets at the rate needed. 1 fig., 2 tabs.

  9. Performance characterization of pneumatic single pellet injection system

    SciTech Connect

    Schuresko, D.D.; Milora, S.L.; Hogan, J.T.; Foster, C.A.; Combs, S.K.

    1982-01-01

    The Oak Ridge National Laboratory single-shot pellet injector, which has been used in plasma fueling experiments on ISX and PDX, has been upgraded and extensively instrumented in order to study the gas dynamics of pneumatic pellet injection. An improved pellet transport line was developed which utilizes a 0.3-cm-diam by 100-cm-long guide tube. Pellet gun performance was characterized by measurements of breech and muzzle dynamic pressures and by pellet velocity and mass determinations. Velocities up to 1.4 km/s were achieved for intact hydrogen pellets using hydrogen propellant at 5-MPa breech pressure. These data have been compared with new pellet acceleration calculations which include the effects of propellant friction, heat transfer, time-dependent boundary conditions, and finite gun geometry. These results provide a basis for the extrapolation of present-day pneumatic injection system performance to velocities in excess of 2 km/s.

  10. The glyoxylate cycle is involved in pleotropic phenotypes, antagonism and induction of plant defence responses in the fungal biocontrol agent Trichoderma atroviride.

    PubMed

    Dubey, Mukesh K; Broberg, Anders; Sooriyaarachchi, Sanjeewani; Ubhayasekera, Wimal; Jensen, Dan Funck; Karlsson, Magnus

    2013-01-01

    Isocitrate lyase (ICL), a signature enzyme of the glyoxylate cycle, is required for metabolism of non-fermentable carbon compounds like acetate or ethanol, and virulence in bacteria and fungi. In the present study, we investigate the role of the glyoxylate cycle in the fungal biocontrol agent Trichoderma atroviride by generating icl deletion and complementation mutants. Phenotypic analyses of the deletion mutant Δicl suggest that ICL is required for normal growth, conidial pigmentation and germination, and abiotic stress tolerance. The Δicl strain display reduced antagonism towards Botrytis cinerea in plate confrontation assays. Secretion and sandwich assays further show that secreted factors are partly responsible for the reduced antagonism. Furthermore, in vitro root colonization assays shows that the Δicl strain retains the ability to internally colonize Arabidopsis thaliana roots. However, the Δicl strain has a reduced ability to induce systemic defence in A. thaliana leaves that results in reduced protection against B. cinerea. These data shows that ICL and the glyoxylate cycle are important for biocontrol traits in T. atroviride, including direct antagonism and induction of defence responses in plants.

  11. 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)

  12. 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.

  13. Identification and Evaluation of Strain B37 of Bacillus subtilis Antagonistic to Sapstain Fungi on Poplar Wood

    PubMed Central

    Zhang, XiaoHua; Zhao, GuiHua; Li, DeWei; Li, ShunPeng; Hong, Qing

    2014-01-01

    Devaluation of poplar products by sapstain accounts for huge and unpredictable losses each year in China. We had isolated four poplar sapstain fungi, Ceratocystis adiposa Hz91, Lasiodiplodia theobromae YM0737, L. theobromae Fx46, and Fusarium sp. YM05, from five poplar varieties and 13 antagonistic bacteria from nine diverse varieties. After being experimented with agar plates, wood chips, and enzyme activities, strain B37 was identified as the best poplar sapstain biocontrol bacterium. The strain B37 was identified as Bacillus subtilis using sequences of the 16S rRNA gene, physiological biochemical, and morphological characteristics. PMID:25401124

  14. Identification and evaluation of strain B37 of Bacillus subtilis antagonistic to sapstain fungi on poplar wood.

    PubMed

    Zhang, XiaoHua; Zhao, GuiHua; Li, DeWei; Li, ShunPeng; Hong, Qing

    2014-01-01

    Devaluation of poplar products by sapstain accounts for huge and unpredictable losses each year in China. We had isolated four poplar sapstain fungi, Ceratocystis adiposa Hz91, Lasiodiplodia theobromae YM0737, L. theobromae Fx46, and Fusarium sp. YM05, from five poplar varieties and 13 antagonistic bacteria from nine diverse varieties. After being experimented with agar plates, wood chips, and enzyme activities, strain B37 was identified as the best poplar sapstain biocontrol bacterium. The strain B37 was identified as Bacillus subtilis using sequences of the 16S rRNA gene, physiological biochemical, and morphological characteristics. PMID:25401124

  15. Pellet stoves wood energy for all

    SciTech Connect

    1995-10-01

    While it`s true that specialized pellet stoves, capable of burning fuels as diverse as reprocessed paper waste and feed corn, are expensive and occasionally clunky, they also represent one of the best hopes for introducing clean burning, reliable renewable energy to those now heating with gas and oil. This article explores the benefits and operation of the stoves including discussions of the following: ecological benefits, combustion, stove venting, ashes, costs, fuels, and the future of wood heat. 1 tab.

  16. 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.

  17. 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.

  18. 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.

  19. 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. PMID:25192611

  20. 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.

  1. 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.

  2. How neutrophils kill fungi.

    PubMed

    Gazendam, Roel P; van de Geer, Annemarie; Roos, Dirk; van den Berg, Timo K; Kuijpers, Taco W

    2016-09-01

    Neutrophils play a critical role in the prevention of invasive fungal infections. Whereas mouse studies have demonstrated the role of various neutrophil pathogen recognition receptors (PRRs), signal transduction pathways, and cytotoxicity in the murine antifungal immune response, much less is known about the killing of fungi by human neutrophils. Recently, novel primary immunodeficiencies have been identified in patients with a susceptibility to fungal infections. These human 'knock-out' neutrophils expand our knowledge to understand the role of PRRs and signaling in human fungal killing. From the studies with these patients it is becoming clear that neutrophils employ fundamentally distinct mechanisms to kill Candida albicans or Aspergillus fumigatus. PMID:27558342

  3. Characteristics of an electron-beam rocket pellet accelerator

    SciTech Connect

    Tsai, C.C.; Foster, C.A.; Milora, S.L.; Schechter, D.E.

    1991-01-01

    A proof-of-principle (POP) electron-beam pellet accelerator has been developed and used for accelerating hydrogen and deuterium pellets. An intact hydrogen pellet was accelerated to a speed of 460 m/s by an electron beam of 13.5 keV. 0.3 A, and 2 ms. The maximum speed is limited by the acceleration path length (0.4 m) and pellet integrity. Experimental data have been collected for several hundred hydrogen pellets, which were accelerated by electron beams with parameters of voltage up to 16 kV, current up to 0.4 A, and pulse length up to 10 ms. Preliminary results reveal that the measured burn velocity increases roughly with the square of the beam voltage, as the theoretical model predicts. The final pellet velocity is proportional to the exhaust velocity, which increases with the beam power. To reach the high exhaust velocity needed for accelerating pellets to >1000 m/s, a new electron gun, with its cathode indirectly heated by a graphite heater and an electron beam, is being developed to increase beam current and power. A rocket casing or shell around the pellet has been designed and developed to increase pellet strength and improve the electron-rocket coupling efficiency. We present the characteristics of this pellet accelerator, including new improvements. 13 refs., 6 figs.

  4. Pellet imaging techniques in the ASDEX tokamak (abstract)

    SciTech Connect

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

    1990-10-01

    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 {ital in} {ital situ} velocity measurements of the pellet as it penetrates the plasma. With time resolution of typically 100 ns and exposures every 50 {mu}s, the evolution of each pellet in a multipellet 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 {ital D}{sub {alpha}}, {ital D}{sub {beta}}, and {ital 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 {ital 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 {ital q} surfaces, but instead are a result of dynamic, nonstationary, ablation process.

  5. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-01-01

    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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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. PMID:20605093

  12. 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. PMID:24397939

  13. 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.

  14. Molecular Systematics of Entomopathogenic Fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  15. 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.

  16. 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).

  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). PMID:24270074

  18. Characteristics of an electron-beam rocket pellet accelerator

    SciTech Connect

    Tsai, C.C.; Foster, C.A.; Schechter, D.E.

    1989-01-01

    An electron-beam rocket pellet accelerator has been designed, built, assembled, and tested as a proof-of-principle (POP) apparatus. The main goal of accelerators based on this concept is to use intense electron-beam heating and ablation of a hydrogen propellant stick to accelerate deuterium and/or tritium pellets to ultrahigh speeds (10 to 20 km/s) for plasma fueling of next-generation fusion devices such as the International Thermonuclear Engineering Reactor (ITER). The POP apparatus is described and initial results of pellet acceleration experiments are presented. Conceptual ultrahigh-speed pellet accelerators are discussed. 14 refs., 8 figs.

  19. Effects of pellet stove on recovery from mental fatigue

    PubMed Central

    Tanaka, Masaaki; Yamada, Hiromi; Nakamura, Takayuki; Watanabe, Yasuyoshi

    2012-01-01

    Summary Background Exposure to a warm environment has been reported to be effective for recovery from mental fatigue. However, there have been no reports examining the effects of a pellet stove on recovery from mental fatigue. The purpose of this study was to examine the effects of a pellet stove on recovery from mental fatigue. Material/Methods In this placebo-controlled, crossover experiment, 16 healthy volunteers were randomized into the pellet stove and control groups. After a 30-min fatigue-inducing mental task session, participants moved to a recovery room with (pellet stove condition) or without (control condition) a pellet stove to see the image of a pellet stove for 30 min. Results After the recovery session, the participants exposed to the pellet stove condition showed lower total error counts of a cognitive test, higher levels of subjective healing, comfort, and warmth, and sympathetic nerve activity and higher parasympathetic nerve activity as compared with the control condition. Conclusions These results provide evidence that improved cognitive function, subjective mental states, and balance of the autonomic nervous activities result from using a pellet stove during the recovery session. Hence, the pellet stove was effective for the recovery from mental fatigue. PMID:22367125

  20. Sintering of wax for controlling release from pellets.

    PubMed

    Singh, Reena; Poddar, S S; Chivate, Amit

    2007-09-14

    The purpose of the present study was to investigate incorporation of hydrophobic (ie, waxy) material into pellets using a thermal sintering technique and to evaluate the pellets in vitro for controlled release. Pellets prepared by extrusion-spheronization technology were formulated with a water-soluble drug, microcrystalline cellulose, and carnauba wax. Powdered carnauba wax (4%-20%) prepared by grinding or by emulsification was studied with an attempt to retard the drug release. The inclusion of ground or emulsified carnauba wax did not sustain the release of theophylline for more than 3 hours. Matrix pellets of theophylline prepared with various concentrations of carnauba wax were sintered thermally at various times and temperatures. In vitro drug release profiles indicated an increase in drug release retardation with increasing carnauba wax concentration. Pellets prepared with ground wax showed a higher standard deviation than did those prepared with emulsified wax. There was incomplete release at the end of 12 hours for pellets prepared with 20% ground or emulsified wax. The sintering temperature and duration were optimized to allow for a sustained release lasting at least 12 hours. The optimized temperature and duration were found to be 100 degrees C and 140 seconds, respectively. The sintered pellets had a higher hydrophobicity than did the unsintered pellets. Scanning electron micrographs indicated that the carnauba wax moved internally, thereby increasing the surface area of wax within the pellets.

  1. Development of Advanced Pellet Injector Systems for Plasma Fueling

    NASA Astrophysics Data System (ADS)

    Sakamoto, Ryuichi; Yamada, Hiroshi; LHD Experimental Group

    Two types of solid hydrogen pellet injection systems have been developed, and plasma refueling experiments have been performed using these pellet injectors. One is an in-situ pipe-gun type pellet injector, which has the simplest design of all pellet injectors. This in-situ pipe-gun injector has 10 injection barrels, each of which can independently inject cylindrical solid hydrogen pellets (3.4 and 3.8 mm in diameter and length, respectively) at velocities up to 1,200 m/s. The other is a repetitive pellet injector with a screw extruder, which can form a 3.0 mmφ solid hydrogen rod continuously at extrusion rates up to 55 mm/s. This extruder allows consecutive pellet injection up to 11 Hz without time limit. Both of these pellet injectors employ compact cryo-coolers to solidify hydrogen; therefore, they can be operated using only electrical input instead of a complicated liquid helium supply system. In particular, using a combination of the repetitive pellet injector with cryo-coolers provides a steady-state capability with minimum maintenance.

  2. 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.

  3. Risk assessment: progress of quarantine biocontrol research on Chinese Tallow, Melaleuca, and Downy Rose Myrtle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  4. Phyllostictines A-D, Oxazatricycloalkenones Produced by Phyllosticta cirsii, A Potential Mycoherbicide for Cirsium arvense Biocontrol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  5. 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

  6. Biological and molecular characterisation of potential biocontrol strains of Trichoderma.

    PubMed

    Turóczi, G; Fekete, C; Kerényi, Z; Nagy, R; Pomázi, A; Hornok, L

    1996-01-01

    Thirty-four strains of seven species of Trichoderma isolated from various fungal sources were compared for direct mycoparasitic activity (MPA), chitinase production and antibiotic activity (ANA) in order to choose the most appropriate partners for a strain-breeding programme. Within species genetic differences were also assesses in T. hamatum, T. harzianum and T. viride by means of random amplification of polymorphic DNA (RAPD). Endochitinase activities of the Trichoderma strains ranged between 20.4 and 1264.5 units/g dry weight of mycelium. The correlation between MPA and chitinase activity was not unambiguous and no correlation existed between MPA and ANA. The RAPD patterns of T. viride strains were highly variable, while isolates of T. harzianum proved to be more uniform; T. hamatum revealed remarkable intraspecific divergence. All these three comprised certain pairs of strains that are promising participants of a strain-improving programme, since their strong genetic affinities offer good changes for combining their contrasted biocontrol traits.

  7. 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.

  8. Adsorption of zinc on magnetite pellets

    SciTech Connect

    Cargnel, D.A.; Cole, C.A.

    1995-12-31

    Zinc is a common contaminant in wastewater electroplating, metal finishing, and many other industrial processes. This paper presents the results of work which is intended to be the first step in an evaluation of the use of concentrated and pelletized magnetite for the adsorption of metals from industrial wastewater. The magnetite used is a cold carbon bonded material which is formulated for the steel industry as a complete product ready for feed to the furnaces. The specific objective of this work was to determine the zinc adsorption capacity of the prepared magnetite pellets through batch tests that were designed to allow the development of an adsorption isotherm. Future work would explore the potential for use of the spent adsorbent in the steel making process, thereby allowing the recovered metals to be recycled into steel products, while avoiding spent adsorbent disposal costs. Although not evaluated in this study, an additional advantage of the use of magnetite as an adsorbent is that it can be magnetically separated from the wastewater.

  9. 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.

  10. 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.

  11. Genetic engineering of filamentous fungi.

    PubMed

    Timberlake, W E; Marshall, M A

    1989-06-16

    Filamentous fungi are important in medicine, industry, agriculture, and basic biological research. For example, some fungal species are pathogenic to humans, whereas others produce beta-lactam antibiotics (penicillin and cephalosporin). Industrial strains produce large amounts of enzymes, such as glucoamylase and proteases, and low molecular weight compounds, such as citric acid. The largest and most economically important group of plant pathogens are fungi. Several fungal species have biological properties and genetic systems that make them ideally suited for basic biological research. Recently developed techniques for genetic engineering of filamentous fungi make it possible to alter their detrimental and beneficial activities in novel ways.

  12. 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).

  13. Air gun pellet injuries: the safety of MR imaging.

    PubMed

    Oliver, C; Kabala, J

    1997-04-01

    The ferromagnetism, and therefore the safety in a magnetic resonance (MR) examination, of the most widely available air gun pellets has been tested. While many are made of lead and are not ferromagnetic, some contain steel and are deflected strongly in a magnetic field. There must therefore be careful consideration before undertaking MR examinations of patients with embedded air gun pellets.

  14. 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. PMID:26856930

  15. 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.

  16. Microstability analysis of pellet fuelled discharges in MAST

    NASA Astrophysics Data System (ADS)

    Garzotti, L.; Figueiredo, J.; Roach, C. M.; Valovič, M.; Dickinson, D.; Naylor, G.; Romanelli, M.; Scannell, R.; Szepesi, G.; the MAST Team

    2014-03-01

    Reactor grade plasmas are likely to be fuelled by pellet injection. This technique transiently perturbs the profiles, driving the density profile hollow and flattening the edge temperature profile. After the pellet perturbation, the density and temperature profiles relax towards their quasi-steady-state shape. Microinstabilities influence plasma confinement and will play a role in determining the evolution of the profiles in pellet fuelled plasmas. In this paper we present the microstability analysis of pellet fuelled H-mode MAST plasmas. Taking advantage of the unique capabilities of the MAST Thomson scattering system and the possibility of synchronizing the eight lasers with the pellet injection, we were able to measure the evolution of the post-pellet electron density and temperature profiles with high temporal and spatial resolution. These profiles, together with ion temperature profiles measured using a charge exchange diagnostic, were used to produce equilibria suitable for microstability analysis of the equilibrium changes induced by pellet injection. This analysis, carried out using the local gyrokinetic code GS2, reveals that the microstability properties are extremely sensitive to the rapid and large transient excursions of the density and temperature profiles, which also change collisionality and βe significantly in the region most strongly affected by the pellet ablation.

  17. Preparation and characterization of a self-emulsifying pellet formulation.

    PubMed

    Abdalla, Ahmed; Mäder, Karsten

    2007-05-01

    The purpose of the current study is to investigate the feasibility of producing solid self-emulsifying pellets using the extrusion/spheronization technique. Pellets were made from a mixture of C18 partial glycerides, Solutol HS15 and microcrystalline cellulose. Pellets with good physical properties (size, shape, friability) and self-emulsifying properties were produced. The pellets were, in contrast to pellets lacking Solutol, able to transfer a lipophilic dye and a spin probe into the aqueous media. The release kinetics and the microenvironment of the pellets during the release process were assessed using electron spin resonance (ESR) spectroscopy. The ESR results showed that the hydrophobic spin probe was localized mainly in the lipid environment all over the release time. Furthermore, the formulation was capable of accelerating the release of the drug diazepam and achieving a diazepam concentration above its saturation solubility. In conclusion, spherical pellets with low friability and self-emulsifying properties can be produced by the standard extrusion/spheronization technique. The pellets are capable of transfering lipophilic compounds into the aqueous phase and have a high potential to increase the bioavailability of lipophilic drugs.

  18. 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.

  19. 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.

  20. 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. PMID:26697226

  1. ["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. PMID:24855739

  2. In vivo evaluation of matrix pellets containing nanocrystalline ketoprofen.

    PubMed

    Vergote, G J; Vervaet, C; Van Driessche, I; Hoste, S; De Smedt, S; Demeester, J; Jain, R A; Ruddy, S; Remon, J P

    2002-06-20

    The aim of this study was to evaluate the in-vivo behaviour of matrix pellets formulated with nanocrystalline ketoprofen after oral administration to dogs. No significant differences in AUC-values were seen between pellet formulations containing nanocrystalline or microcrystalline ketoprofen and a commercial ketoprofen formulation (reference: Rofenid 200 Long Acting). C(max) of the formulations containing nano- or microcrystalline ketoprofen was significantly higher compared to reference, whereas t(max) was significantly lower. The in-vivo burst release observed for the spray dried nanocrystalline ketoprofen matrix pellets was reduced following compression of the pellets in combination with placebo wax/starch pellets. These matrix tablets sustained the ketoprofen plasma concentrations during 5.6 and 5.4 h for formulations containing nano- and microcrystalline ketoprofen, respectively.

  3. 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.

  4. 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)

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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. PMID:25746637

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  16. 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.

  17. LTR Retrotransposons in Fungi

    PubMed Central

    Muszewska, Anna; Hoffman-Sommer, Marta; Grynberg, Marcin

    2011-01-01

    Transposable elements with long terminal direct repeats (LTR TEs) are one of the best studied groups of mobile elements. They are ubiquitous elements present in almost all eukaryotic genomes. Their number and state of conservation can be a highlight of genome dynamics. We searched all published fungal genomes for LTR-containing retrotransposons, including both complete, functional elements and remnant copies. We identified a total of over 66,000 elements, all of which belong to the Ty1/Copia or Ty3/Gypsy superfamilies. Most of the detected Gypsy elements represent Chromoviridae, i.e. they carry a chromodomain in the pol ORF. We analyzed our data from a genome-ecology perspective, looking at the abundance of various types of LTR TEs in individual genomes and at the highest-copy element from each genome. The TE content is very variable among the analyzed genomes. Some genomes are very scarce in LTR TEs (<50 elements), others demonstrate huge expansions (>8000 elements). The data shows that transposon expansions in fungi usually involve an increase both in the copy number of individual elements and in the number of element types. The majority of the highest-copy TEs from all genomes are Ty3/Gypsy transposons. Phylogenetic analysis of these elements suggests that TE expansions have appeared independently of each other, in distant genomes and at different taxonomical levels. We also analyzed the evolutionary relationships between protein domains encoded by the transposon pol ORF and we found that the protease is the fastest evolving domain whereas reverse transcriptase and RNase H evolve much slower and in correlation with each other. PMID:22242120

  18. 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

  19. 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.

  20. 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. PMID:26644135

  1. 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.

  2. Dependency between removal characteristics and defined measurement categories of pellets

    NASA Astrophysics Data System (ADS)

    Vogt, C.; Rohrbacher, M.; Rascher, R.; Sinzinger, S.

    2015-09-01

    Optical surfaces are usually machined by grinding and polishing. To achieve short polishing times it is necessary to grind with best possible form accuracy and with low sub surface damages. This is possible by using very fine grained grinding tools for the finishing process. These however often show time dependent properties regarding cutting ability in conjunction with tool wear. Fine grinding tools in the optics are often pellet-tools. For a successful grinding process the tools must show a constant self-sharpening performance. A constant, at least predictable wear and cutting behavior is crucial for a deterministic machining. This work describes a method to determine the characteristics of pellet grinding tools by tests conducted with a single pellet. We investigate the determination of the effective material removal rate and the derivation of the G-ratio. Especially the change from the newly dressed via the quasi-stationary to the worn status of the tool is described. By recording the achieved roughness with the single pellet it is possible to derive the roughness expect from a series pellet tool made of pellets with the same specification. From the results of these tests the usability of a pellet grinding tool for a specific grinding task can be determined without testing a comparably expensive serial tool. The results are verified by a production test with a serial tool under series conditions. The collected data can be stored and used in an appropriate data base for tool characteristics and be combined with useful applications.

  3. Preparation and evaluation of sustained-release doxazosin mesylate pellets.

    PubMed

    Ha, Jung-Myung; Kim, Ju-Young; Oh, Tack-Oon; Rhee, Yun-Seok; Chi, Sang-Cheol; Kuk, Hyon; Park, Chun-Woong; Park, Eun-Seok

    2013-01-01

    Doxazosin mesylate (DXM) sustained release pellets were prepared by an extrusion-spheronization and fluid-bed coating technique. The core pellets containing DXM were prepared by extrusion-spheronization technique, and coated by a fluid-bed coater to control the release of DXM. The factors affecting to properties of pellets, such as diluent content, type and coating level of coating agents and plasticizers were studied in the present study. Polymethacrylate derivatives (Eudragit® RS PO and RL PO) were used for coating agents, and polyethylene glycol 6000 (PEG 6000), triethyl citrate (TEC) and castor oil were as plasticizers. To evaluate the properties of prepared pellets, the size of prepared pellets was investigated by sieve analysis technique and the morphology of pellets was evaluated by scanning electron microscopy. Through the dissolution test, factors that have an effect on the dissolution of the drug were evaluated. As the content ratio of microcrystalline cellulose (MCC) had increased, the dissolution was proportionally sustained. Eudragit® RS PO had more marked sustaining effect on the dissolution rate than Eudragit® RL PO, and the effect was more pronounced with the increased coating level. PEG 6000 was an appropriate plasticizer for DXM pellets, and increasing the content of PEG 6000, was also slightly decreasing the dissolution rate.

  4. 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.

  5. An oral controlled release matrix pellet formulation containing nanocrystalline ketoprofen.

    PubMed

    Vergote, G J; Vervaet, C; Van Driessche, I; Hoste, S; De Smedt, S; Demeester, J; Jain, R A; Ruddy, S; Remon, J P

    2001-05-21

    A controlled release pellet formulation using a NanoCrystal colloidal dispersion of ketoprofen was developed. In order to be able to process the aqueous NanoCrystal colloidal dispersion into a hydrophobic solid dosage form a spray drying procedure was used. The in vitro dissolution profiles of wax based pellets loaded with nanocrystalline ketoprofen are compared with the profiles of wax based pellets loaded with microcrystalline ketoprofen and of a commercial sustained release ketoprofen formulation. Pellets were produced using a melt pelletisation technique. All pellet formulations were composed of a mixture of microcrystalline wax and starch derivatives. The starch derivatives used were waxy maltodextrin and drum dried corn starch. Varying the concentration of drum dried corn starch increased the release rate of ketoprofen but the ketoprofen recovery remained problematic. To increase the dissolution yield surfactants were utilised. The surfactants were either added during the production process of the NanoCrystal colloidal dispersion (sodium laurylsulphate) or during the pellet manufacturing process (Cremophor RH 40). Both methods resulted in a sustained but complete release of nanocrystalline ketoprofen from the matrix pellet formulations.

  6. Influence of pellet size on rat's hoarding behavior.

    PubMed

    Charron, I; Cabanac, M

    2004-09-15

    The body weight threshold for hoarding behavior of rats is routinely used as a means to discern an animal's body weight regulation. We explored whether the size of food pellets would modify hoarding and the hoarding threshold. In Experiment 1, we offered the rats either large (ca. 5 g) or small (ca. 2 g) food pellets on alternate days while keeping their body weights within a narrow range when they were not in the hoarding sessions. The hoarding threshold was not influenced, by food size (312+/-32 g small and 298+/-13 g large pellets, N.S.). On the other hand, the relationship between hoarded food and body mass significantly differed between small and large pellets (ratio of 2.7). Because such a ratio was similar to that of the respective pellet weights, this suggests that the more the rat is deprived of food, the more willing it is, in a predetermined manner, to move about in search of food. Experiment 2 verified this hypothesis: instead of weighing the food hoarded, we counted the number of pellets hoarded. The slopes of the regression lines were similar in both cases, when the pellets were counted and when the hoarded food was weighed. Results showed no significant differences between these two approaches, suggesting that the weight of hoarded food is a good indicator of the number of trips from home to food in the hoarding experiment.

  7. Pellet injection in the RFP (Reversed Field Pinch)

    SciTech Connect

    Wurden, G.A.; Weber, P.G.; Munson, C.P.; Cayton, T.E.; Bunting, C.A.; Carolan, P.G.

    1988-01-01

    Observation of pellets injected into the ZT-40M Reversed Field Pinch has allowed a new twist on the usual tokamak ablation physics modeling. The RFP provides a strong ohmic heating regime with relatively high electron drift parameter (xi/sub drift/ /approximately/ 0.2), in the presence of a highly sheared magnetic field geometry. In situ photos of the pellet ablation cloud using a grated-intensified CCD camera, as well as two-view integrated photos of the pellet trajectory show substantial modification of the original pellet trajectory, in both direction and speed. Depending on the launch geometry, increases in the initial 500 m/s pellet speed by 50% have been observed, and a ski jump deflector plate in the launch port has been used to counteract strong poloidal curvature. In contrast to the tokamak, the D/sub ..cap alpha../ light signature is strongest near the edge, and weaker in the plasma center. Additional information on ion temperature response to pellet injection with 20 ..mu..sec time resolution has been obtained using a 5-channel neutral particle analyzer (NPA). The energy confinement is transiently degraded while the beta is largely unchanged. This may be indicative of pellet injection into a high-beta plasma operating at fixed beta. 10 refs., 6 figs.

  8. Mechanisms of phosphorus removal by cement-bound ochre pellets.

    PubMed

    Littler, James; Geroni, Jennifer N; Sapsford, Devin J; Coulton, Richard; Griffiths, Anthony J

    2013-01-01

    Hydrous ferric oxide (here termed 'ochre') sludge, an abundant waste product produced from the treatment of acid mine drainage (AMD), was used in this study for the removal of phosphorus (in the form of phosphate ions) from contaminated waters. The phosphorus uptake capacities of both raw and pelletized AMD solids were compared using batch and column tests. Addition of a cement binder to the AMD solids during pellet production led to significantly increased P-loading of the resultant solids compared to the raw sludge. Additionally, the pellets were found to continue to remove P in tests up to 7 d in duration whereas the unbound AMD sludge appeared to approach equilibrium with phosphate solution after approximately 60 min of contact time. In line with previous studies P uptake by the AMD solids was found to be primarily via adsorption. By contrast calcium phosphate precipitation was found to be the dominant removal mechanism for the cement-bound ochre pellets with a relatively small proportion of removal attributable to the AMD solids. SEM-EDX analysis of the surface of used pellets showed a Ca:P molar ratio close to that of hydroxyapatite (HAP). Continuous column tests on these pellets showed a rapid decrease in P removal capacity by the pellets over time, attributable to the formation of a passivating HAP surface layer. PMID:23041038

  9. Pyrolysis of ground pine chip and ground pellet particles

    DOE PAGESBeta

    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 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

  10. 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.

  11. Electron-beam rocket acceleration of hydrogen pellets

    NASA Astrophysics Data System (ADS)

    Tsai, C. C.; Foster, C. A.; Milora, S. L.; Schechter, D. E.; Whealton, J. H.

    A proof-of-principle device for characterizing electron-beam rocket pellet acceleration has been developed and operated during the last few years. Experimental data have been collected for thousands of accelerated hydrogen pellets under a variety of beam conditions. One intact hydrogen pellet was accelerated to a speed of 578 m/s by an electron beam of 10 kV, 0.8 A, and I ms. The collected data reveal the significant finding that the measured bum velocity of bare hydrogen pellets increases with the square of the beam voltage in a way that is qualitatively consistent with the theoretical prediction based on the neutral gas shielding (NGS) model. The measured bum velocity increases with the beam current or power and then saturates at values two to three times greater than that predicted by the NGS model. The discrepancy may result from low pellet strength and large beam-pellet interaction areas. Moreover, this feature may be the cause of the low measured exhaust velocity, which often exceeds the sonic velocity of the ablated gas. Consistent with the NGS model, the measured exhaust velocity increases in direct proportion to the beam current and in inverse proportion to the beam voltage. To alleviate the pellet strength problem, experiments have been performed with the hydrogen ice contained in a lightweight rocket casing or shell. Pellets in such sabots have the potential to withstand higher beam powers and achieve higher thrust-coupling efficiency. Some experimental results are reported and ways of accelerating pellets to higher velocity are discussed.

  12. Impact of a Recombinant Biocontrol Bacterium, Pseudomonas fluorescens pc78, on Microbial Community in Tomato Rhizosphere.

    PubMed

    Kong, Hyun Gi; Kim, Nam Hee; Lee, Seung Yeup; Lee, Seon-Woo

    2016-04-01

    Pseudomonas fluorescens pc78 is an effective biocontrol agent for soil-borne fungal diseases. We previously constructed a P43-gfp tagged biocontrol bacteria P. fluorescens pc78-48 to investigate bacterial traits in natural ecosystem and the environmental risk of genetically modified biocontrol bacteria in tomato rhizosphere. Fluctuation of culturable bacteria profile, microbial community structure, and potential horizontal gene transfer was investigated over time after the bacteria treatment to the tomato rhizosphere. Tagged gene transfer to other organisms such as tomato plants and bacteria cultured on various media was examined by polymerase chain reaction, using gene specific primers. Transfer of chromosomally integrated P43-gfp from pc78 to other organisms was not apparent. Population and colony types of culturable bacteria were not significantly affected by the introduction of P. fluorescens pc78 or pc78-48 into tomato rhizosphere. Additionally, terminal restriction fragment length polymorphism profiles were investigated to estimate the influence on the microbial community structure in tomato rhizosphere between non-treated and pc78-48-treated samples. Interestingly, rhizosphere soil treated with strain pc78-48 exhibited a significantly different bacterial community structure compared to that of non-treated rhizosphere soil. Our results suggest that biocontrol bacteria treatment influences microbial community in tomato rhizosphere, while the chromosomally modified biocontrol bacteria may not pose any specific environmental risk in terms of gene transfer. PMID:27147933

  13. Impact of a Recombinant Biocontrol Bacterium, Pseudomonas fluorescens pc78, on Microbial Community in Tomato Rhizosphere.

    PubMed

    Kong, Hyun Gi; Kim, Nam Hee; Lee, Seung Yeup; Lee, Seon-Woo

    2016-04-01

    Pseudomonas fluorescens pc78 is an effective biocontrol agent for soil-borne fungal diseases. We previously constructed a P43-gfp tagged biocontrol bacteria P. fluorescens pc78-48 to investigate bacterial traits in natural ecosystem and the environmental risk of genetically modified biocontrol bacteria in tomato rhizosphere. Fluctuation of culturable bacteria profile, microbial community structure, and potential horizontal gene transfer was investigated over time after the bacteria treatment to the tomato rhizosphere. Tagged gene transfer to other organisms such as tomato plants and bacteria cultured on various media was examined by polymerase chain reaction, using gene specific primers. Transfer of chromosomally integrated P43-gfp from pc78 to other organisms was not apparent. Population and colony types of culturable bacteria were not significantly affected by the introduction of P. fluorescens pc78 or pc78-48 into tomato rhizosphere. Additionally, terminal restriction fragment length polymorphism profiles were investigated to estimate the influence on the microbial community structure in tomato rhizosphere between non-treated and pc78-48-treated samples. Interestingly, rhizosphere soil treated with strain pc78-48 exhibited a significantly different bacterial community structure compared to that of non-treated rhizosphere soil. Our results suggest that biocontrol bacteria treatment influences microbial community in tomato rhizosphere, while the chromosomally modified biocontrol bacteria may not pose any specific environmental risk in terms of gene transfer.

  14. Impact of a Recombinant Biocontrol Bacterium, Pseudomonas fluorescens pc78, on Microbial Community in Tomato Rhizosphere

    PubMed Central

    Kong, Hyun Gi; Kim, Nam Hee; Lee, Seung Yeup; Lee, Seon-Woo

    2016-01-01

    Pseudomonas fluorescens pc78 is an effective biocontrol agent for soil-borne fungal diseases. We previously constructed a P43-gfp tagged biocontrol bacteria P. fluorescens pc78-48 to investigate bacterial traits in natural ecosystem and the environmental risk of genetically modified biocontrol bacteria in tomato rhizosphere. Fluctuation of culturable bacteria profile, microbial community structure, and potential horizontal gene transfer was investigated over time after the bacteria treatment to the tomato rhizosphere. Tagged gene transfer to other organisms such as tomato plants and bacteria cultured on various media was examined by polymerase chain reaction, using gene specific primers. Transfer of chromosomally integrated P43-gfp from pc78 to other organisms was not apparent. Population and colony types of culturable bacteria were not significantly affected by the introduction of P. fluorescens pc78 or pc78-48 into tomato rhizosphere. Additionally, terminal restriction fragment length polymorphism profiles were investigated to estimate the influence on the microbial community structure in tomato rhizosphere between non-treated and pc78-48-treated samples. Interestingly, rhizosphere soil treated with strain pc78-48 exhibited a significantly different bacterial community structure compared to that of non-treated rhizosphere soil. Our results suggest that biocontrol bacteria treatment influences microbial community in tomato rhizosphere, while the chromosomally modified biocontrol bacteria may not pose any specific environmental risk in terms of gene transfer. PMID:27147933

  15. Biocontrol of the Potato Blackleg and Soft Rot Diseases Caused by Dickeya dianthicola

    PubMed Central

    Raoul des Essarts, Yannick; Cigna, Jérémy; Quêtu-Laurent, Angélique; Caron, Aline; Munier, Euphrasie; Beury-Cirou, Amélie

    2015-01-01

    Development of protection tools targeting Dickeya species is an important issue in the potato production. Here, we present the identification and the characterization of novel biocontrol agents. Successive screenings of 10,000 bacterial isolates led us to retain 58 strains that exhibited growth inhibition properties against several Dickeya sp. and/or Pectobacterium sp. pathogens. Most of them belonged to the Pseudomonas and Bacillus genera. In vitro assays revealed a fitness decrease of the tested Dickeya sp. and Pectobacterium sp. pathogens in the presence of the biocontrol agents. In addition, four independent greenhouse assays performed to evaluate the biocontrol bacteria effect on potato plants artificially contaminated with Dickeya dianthicola revealed that a mix of three biocontrol agents, namely, Pseudomonas putida PA14H7 and Pseudomonas fluorescens PA3G8 and PA4C2, repeatedly decreased the severity of blackleg symptoms as well as the transmission of D. dianthicola to the tuber progeny. This work highlights the use of a combination of biocontrol strains as a potential strategy to limit the soft rot and blackleg diseases caused by D. dianthicola on potato plants and tubers. PMID:26497457

  16. Regulation of morphogenesis and biocontrol properties in Trichoderma virens by a VELVET protein, Vel1.

    PubMed

    Mukherjee, Prasun K; Kenerley, Charles M

    2010-04-01

    Mycoparasitic strains of Trichoderma are applied as commercial biofungicides for control of soilborne plant pathogens. Although the majority of commercial biofungicides are Trichoderma based, chemical pesticides, which are ecological and environmental hazards, still dominate the market. This is because biofungicides are not as effective or consistent as chemical fungicides. Efforts to improve these products have been limited by a lack of understanding of the genetic regulation of biocontrol activities. In this study, using gene knockout and complementation, we identified the VELVET protein Vel1 as a key regulator of biocontrol, as well as morphogenetic traits, in Trichoderma virens, a commercial biocontrol agent. Mutants with mutations in vel1 were defective in secondary metabolism (antibiosis), mycoparasitism, and biocontrol efficacy. In nutrient-rich media they also lacked two types of spores important for survival and development of formulation products: conidia (on agar) and chlamydospores (in liquid shake cultures). These findings provide an opportunity for genetic enhancement of biocontrol and industrial strains of Trichoderma, since Vel1 is very highly conserved across three Trichoderma species.

  17. Surfactin triggers biofilm formation of Bacillus subtilis in melon phylloplane and contributes to the biocontrol activity.

    PubMed

    Zeriouh, Houda; de Vicente, Antonio; Pérez-García, Alejandro; Romero, Diego

    2014-07-01

    The biocontrol activity of many Bacillus species has been traditionally related to the direct antagonism of pathogens. In previous works, we reported that B. subtilis strain UMAF6614 was an efficient biocontrol agent that produced bacillomycin, fengycin and surfactin lipopeptides. Bacillomycins and fengycins were shown to have antagonistic activity towards fungal and bacterial pathogens of cucurbits; however, the functionality of surfactin remained unclear. In this study, the role of surfactin in the biocontrol activity of this strain was investigated. We observed that a deficiency in surfactin production led to a partial reduction of disease suppression by this biocontrol agent, which coincided with a defect in biofilm formation and the colonization of the melon phylloplane. These effects were due to a dramatic reduction in the production of exopolysaccharide and the TasA protein, which are the two major components of the extracellular matrix. We propose that the biocontrol activity of this strain is the result of the coordinated action of the three families of lipopeptides. B. subtilis UMAF6614 produces surfactin to trigger biofilm formation on melon phylloplane, which ensures the long-term persistence and the adequate secretion of suppressive lipopeptides, bacillomycins and fengycins, which efficiently target pathogens.

  18. Ochratoxin A management in vineyards by Lobesia botrana biocontrol.

    PubMed

    Cozzi, Giuseppe; Somma, Stefania; Haidukowski, Miriam; Logrieco, Antonio F

    2013-01-01

    Grape berries attacked by Lobesia botrana larvae are more easily infected by Aspergillus section Nigri (black aspergilli) ochratoxigenic species. Two-year field trials were carried out in Apulia (Italy) to evaluate a bioinsecticide control strategy against L. botrana and the indirect effect on reducing ochratoxin A (OTA) contamination in vineyards. A commercial Bacillus thuringiensis formulate and an experimental Beauveria bassiana (ITEM-1559) formulate were tested in two vineyards cultivated with the same grape variety, Negroamaro, but with two different training systems (espalier and little-arbor techniques). In both years and training systems the treatments by B. bassiana ITEM-1559 significantly controlled L. botrana larvae attacks with effectiveness similar to B. thuringensis (more than 20%). A significant reduction of OTA concentrations (up to 80% compared to untreated controls) was observed only in the first year in both training systems, when the metereological parameters prior to harvest were more favorable to the insect attack. Results of field trials showed that B. bassiana ITEM-1559 is a valid bioinsecticide against L. botrana and that grape moth biocontrol is a strategy to reduce OTA contamination in vineyard in seasons with heavy natural infestation.

  19. Ochratoxin A Management in Vineyards by Lobesia botrana Biocontrol

    PubMed Central

    Cozzi, Giuseppe; Somma, Stefania; Haidukowski, Miriam; Logrieco, Antonio F.

    2013-01-01

    Grape berries attacked by Lobesia botrana larvae are more easily infected by Aspergillus section Nigri (black aspergilli) ochratoxigenic species. Two-year field trials were carried out in Apulia (Italy) to evaluate a bioinsecticide control strategy against L. botrana and the indirect effect on reducing ochratoxin A (OTA) contamination in vineyards. A commercial Bacillus thuringiensis formulate and an experimental Beauveria bassiana (ITEM-1559) formulate were tested in two vineyards cultivated with the same grape variety, Negroamaro, but with two different training systems (espalier and little-arbor techniques). In both years and training systems the treatments by B. bassiana ITEM-1559 significantly controlled L. botrana larvae attacks with effectiveness similar to B. thuringensis (more than 20%). A significant reduction of OTA concentrations (up to 80% compared to untreated controls) was observed only in the first year in both training systems, when the metereological parameters prior to harvest were more favorable to the insect attack. Results of field trials showed that B. bassiana ITEM-1559 is a valid bioinsecticide against L. botrana and that grape moth biocontrol is a strategy to reduce OTA contamination in vineyard in seasons with heavy natural infestation. PMID:23282670

  20. The Pochonia chlamydosporia Serine Protease Gene vcp1 Is Subject to Regulation by Carbon, Nitrogen and pH: Implications for Nematode Biocontrol

    PubMed Central

    Ward, Elaine; Kerry, Brian R.; Manzanilla-López, Rosa H.; Mutua, Gerald; Devonshire, Jean; Kimenju, John; Hirsch, Penny R.

    2012-01-01

    The alkaline serine protease VCP1 of the fungus Pochonia chlamydosporia belongs to a family of subtilisin-like enzymes that are involved in infection of nematode and insect hosts. It is involved early in the infection process, removing the outer proteinaceous vitelline membrane of nematode eggs. Little is known about the regulation of this gene, even though an understanding of how nutrients and other factors affect its expression is critical for ensuring its efficacy as a biocontrol agent. This paper provides new information on the regulation of vcp1 expression. Sequence analysis of the upstream regulatory region of this gene in 30 isolates revealed that it was highly conserved and contained sequence motifs characteristic of genes that are subject to carbon, nitrogen and pH-regulation. Expression studies, monitoring enzyme activity and mRNA, confirmed that these factors affect VCP1 production. As expected, glucose reduced VCP1 expression and for a few hours so did ammonium chloride. Surprisingly, however, by 24 h VCP1 levels were increased in the presence of ammonium chloride for most isolates. Ambient pH also regulated VCP1 expression, with most isolates producing more VCP1 under alkaline conditions. There were some differences in the response of one isolate with a distinctive upstream sequence including a variant regulatory-motif profile. Cryo-scanning electron microscopy studies indicated that the presence of nematode eggs stimulates VCP1 production by P. chlamydosporia, but only where the two are in close contact. Overall, the results indicate that readily-metabolisable carbon sources and unfavourable pH in the rhizosphere/egg-mass environment may compromise nematode parasitism by P. chlamydosporia. However, contrary to previous indications using other nematophagous and entomopathogenic fungi, ammonium nitrate (e.g. from fertilizers) may enhance biocontrol potential in some circumstances. PMID:22558192

  1. 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.

  2. Methods of Nitrogen Oxide Reduction in Pellet Boilers

    NASA Astrophysics Data System (ADS)

    Zandeckis, Aivars; Blumberga, Dagnija; Rochas, Claudio; Veidenbergs, Ivars; Silins, Kaspars

    2010-01-01

    The main goal of this research was to create and test technical solutions that reduce nitrogen oxide emissions in low-capacity pellet boiler. During the research, wood pellets were incinerated in a pellet boiler produced in Latvia with a rated capacity of 15 kW. During the research two NOx emission reduction methods were tested: secondary air supply in the chamber and recirculation of flue gases. Results indicated a drop of NOx concentration only for flue gas recirculation methods. Maximum reduction of 21% was achieved.

  3. 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.

  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. 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. PMID:25430370

  7. 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.

  8. Viability of marine phytoplankton in zooplankton fecal pellets

    NASA Astrophysics Data System (ADS)

    Fowler, S. W.; Fisher, N. S.

    1983-09-01

    Zooplankton fecal pellets collected from sediment traps or freshly excreted by euphausiids grazing in situ at natural phytoplankton levels in the pelagic Mediterranean were incubated under laboratory conditions and always contained viable marine phytoplankton, usually diatoms. Fecal pellets excreted by euphausiids grazing in the laboratory on unialgal diets also contained living cells, indicating viable gut passage of some species. The rapid sinking of fecal pellets appears to be an effective mechanism for transporting living algae to depth and possibly in seeding marine waters and sediments with such cells.

  9. Draft Genome Sequence of Chryseobacterium sp. Strain GSE06, a Biocontrol Endophytic Bacterium Isolated from Cucumber (Cucumis sativus).

    PubMed

    Jeong, Jin-Ju; Park, Byeong Hyeok; Park, Hongjae; Choi, In-Geol; Kim, Ki Deok

    2016-06-16

    Chryseobacterium sp. strain GSE06 is a biocontrol endophytic bacterium against the destructive soilborne oomycete Phytophthora capsici, which causes Phytophthora blight of pepper. Here, we present its draft genome sequence, which contains genes related to biocontrol traits, such as colonization, antimicrobial activity, plant growth promotion, and abiotic or biotic stress adaptation.

  10. Draft Genome Sequence of Chryseobacterium sp. Strain GSE06, a Biocontrol Endophytic Bacterium Isolated from Cucumber (Cucumis sativus).

    PubMed

    Jeong, Jin-Ju; Park, Byeong Hyeok; Park, Hongjae; Choi, In-Geol; Kim, Ki Deok

    2016-01-01

    Chryseobacterium sp. strain GSE06 is a biocontrol endophytic bacterium against the destructive soilborne oomycete Phytophthora capsici, which causes Phytophthora blight of pepper. Here, we present its draft genome sequence, which contains genes related to biocontrol traits, such as colonization, antimicrobial activity, plant growth promotion, and abiotic or biotic stress adaptation. PMID:27313310

  11. Draft Genome Sequence of a Biocontrol Rhizobacterium, Chryseobacterium kwangjuense Strain KJ1R5, Isolated from Pepper (Capsicum annuum)

    PubMed Central

    Jeong, Jin-Ju; Park, Hongjae; Park, Byeong Hyeok; Mannaa, Mohamed; Sang, Mee Kyung

    2016-01-01

    Strain KJ1R5 of the rhizobacterium Chryseobacterium kwangjuense is an effective biocontrol agent against Phytophthora blight of pepper caused by a destructive soilborne oomycete, Phytophthora capsici. Here, we present the draft genome sequence of strain KJ1R5, which contains genes related to biocontrol, plant growth promotion, and environmental stress adaptation. PMID:27103726

  12. Draft Genome Sequence of Chryseobacterium sp. Strain GSE06, a Biocontrol Endophytic Bacterium Isolated from Cucumber (Cucumis sativus)

    PubMed Central

    Jeong, Jin-Ju; Park, Byeong Hyeok; Park, Hongjae

    2016-01-01

    Chryseobacterium sp. strain GSE06 is a biocontrol endophytic bacterium against the destructive soilborne oomycete Phytophthora capsici, which causes Phytophthora blight of pepper. Here, we present its draft genome sequence, which contains genes related to biocontrol traits, such as colonization, antimicrobial activity, plant growth promotion, and abiotic or biotic stress adaptation. PMID:27313310

  13. 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

  14. Proteome Studies of Filamentous Fungi

    SciTech Connect

    Baker, Scott E.; Panisko, Ellen A.

    2011-04-20

    The continued fast pace of fungal genome sequence generation has enabled proteomic analysis of a wide breadth of organisms that span the breadth of the Kingdom Fungi. There is some phylogenetic bias to the current catalog of fungi with reasonable DNA sequence databases (genomic or EST) that could be analyzed at a global proteomic level. However, the rapid development of next generation sequencing platforms has lowered the cost of genome sequencing such that in the near future, having a genome sequence will no longer be a time or cost bottleneck for downstream proteomic (and transcriptomic) analyses. High throughput, non-gel based proteomics offers a snapshot of proteins present in a given sample at a single point in time. There are a number of different variations on the general method and technologies for identifying peptides in a given sample. We present a method that can serve as a “baseline” for proteomic studies of fungi.

  15. 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.

  16. Gasification of pelletized biomass in a pilot scale downdraft gasifier.

    PubMed

    Simone, Marco; Barontini, Federica; Nicolella, Cristiano; Tognotti, Leonardo

    2012-07-01

    This work presents a pilot-scale investigation aimed at assessing the feasibility and reliability of biomass pellet gasification. Wood sawdust and sunflower seeds pellets were tested in a 200 kW downdraft gasifier operating with air as gasifying agent. The gasification of pelletized biomass led to rather high and unstable pressure drops, reducing the gasifier productivity and stability. Furthermore the generation of fine residues compromised the operation of wet ash removal systems. On the other hand, good syngas compositions (H(2) 17.2%, N(2) 46.0%, CH(4) 2.5%, CO 21.2%, CO(2) 12.6%, and C(2)H(4) 0.4%), specific gas production (2.2-2.4 N m(3) kg(-1)) and cold gas efficiency (67.7-70.0%) were achieved. For these reasons pelletized biomass should be considered only as complementary fuel in co-gasification with other feedstock. PMID:22537399

  17. Cell Electrofusion in Centrifuged Erythrocyte Pellets Assessed by Dielectric Spectroscopy.

    PubMed

    Asami, Koji

    2016-04-01

    We have characterized cell electrofusion in cell pellets by dielectric spectroscopy. Cell pellets were formed from horse erythrocyte suspensions by centrifugation and were subjected to intense AC pulses. The dielectric spectra of the pellets were measured over a frequency range of 10 Hz to 10 MHz. The application of AC pulses caused low-frequency (LF) dielectric relaxation below about 100 kHz. The LF dielectric relaxation was markedly affected not only by pretreatment of cells at 50 °C, which disrupts the spectrin network of erythrocytes, but also by the parameters of the AC pulses (frequency of the sine wave and repeat count of the pulses). The occurrence of the LF dielectric relaxation was qualitatively accounted for by modeling fusion products in the pellet by prolate spheroidal cells whose long axes run parallel to the applied electric field.

  18. 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.

  19. Energetic ion diagnostics using neutron flux measurements during pellet injection

    SciTech Connect

    Heidbrink, W.W.

    1986-01-01

    Neutron measurements during injection of deuterium pellets into deuterium plasmas on the Tokamak Fusion Test Reactor (TFTR) indicate that the fractional increase in neutron emission about 0.5 msec after pellet injection is proportional to the fraction of beam-plasma reactions to total fusion reactions in the unperturbed plasma. These observations suggest three diagnostic applications of neutron measurements during pellet injection: (1) measurement of the beam-plasma reaction rate in deuterium plasmas for use in determining the fusion Q in an equivalent deuterium-tritium plasma, (2) measurement of the radial profile of energetic beam ions by varying the pellet size and velocity, and (3) measurement of the ''temperature'' of ions accelerated during wave heating. 18 refs., 3 figs.

  20. Effects of pelletized anticoagulant rodenticides on California quail.

    PubMed

    Blus, L J; Henny, C J; Grove, R A

    1985-10-01

    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. PMID:4078974

  1. PCB metabolism by ectomycorrhizal fungi

    SciTech Connect

    Donnelly, P.K.; Fletcher, J.S.

    1995-04-01

    Since 1976 the use of polychlorinated biphenyls (PCBs) has been banned in the U.S. Prior to this, commercial mixtures (Aroclors) had been used extensively as an industrial lubricant because of their nonflammable, nonreactive properties. These same properties are responsible for their persistent in the environment where they bind to soil particles and resist biodegradation. Decontamination of PCB-laden soil is expensive with excavation followed by either storage or incineration as the primary means of remediation. The use of microorganisms for PCB bioremediation has been gaining popularity in the past few years. Bacteria and/or fungi isolated from environmental samples have been used to degrade PCBs under laboratory conditions, but in field trials they have not been as effective. The most common explanation for the poor performance of PCB-degrading organisms introduced at contaminated sites is that they do not compete well with the existing populations. Plant-ectomycorrhizal systems may overcome this problem. Introduction and cultivation of a known host plant at a contaminated site has the potential of providing a survival advantage for ectomycorrhizal fungi that normally colonize the roots of the introduced plant. Ectomycorrhizal fungi exist naturally in the soil and normally grow in association with the roots of a host plant in a mutualistic symbiotic relationship. Preliminary in vitro examination of this group of fungi for their ability to enzymatically degrade xenobiotics is very promising. In vivo studies have shown that some of these fungi have the ability to degrade chlorinated, aromatic compounds, such as 2,4-D and atrazine. The aspect of ectomycorrhizal metabolism was investigated further in the current study by determining the ability of 21 different fungi to metabolize 19 different PCB congeners with varying chlorine content and substitution patterns. 13 refs., 1 fig., 2 tabs.

  2. Antifungal Rhizosphere Bacteria Can increase as Response to the Presence of Saprotrophic Fungi.

    PubMed

    de Boer, Wietse; Hundscheid, Maria P J; Klein Gunnewiek, Paulien J A; de Ridder-Duine, Annelies S; Thion, Cecile; van Veen, Johannes A; van der Wal, Annemieke

    2015-01-01

    Knowledge on the factors that determine the composition of bacterial communities in the vicinity of roots (rhizosphere) is essential to understand plant-soil interactions. Plant species identity, plant growth stage and soil properties have been indicated as major determinants of rhizosphere bacterial community composition. Here we show that the presence of saprotrophic fungi can be an additional factor steering rhizosphere bacterial community composition and functioning. We studied the impact of presence of two common fungal rhizosphere inhabitants (Mucor hiemalis and Trichoderma harzianum) on the composition of cultivable bacterial communities developing in the rhizosphere of Carex arenaria (sand sedge) in sand microcosms. Identification and phenotypic characterization of bacterial isolates revealed clear shifts in the rhizosphere bacterial community composition by the presence of two fungal strains (M. hiemalis BHB1 and T. harzianum PvdG2), whereas another M. hiemalis strain did not show this effect. Presence of both M. hiemalis BHB1 and T. harzianum PvdG2 resulted in a significant increase of chitinolytic and (in vitro) antifungal bacteria. The latter was most pronounced for M. hiemalis BHB1, an isolate from Carex roots, which stimulated the development of the bacterial genera Achromobacter and Stenotrophomonas. In vitro tests showed that these genera were strongly antagonistic against M. hiemalis but also against the plant-pathogenic fungus Rhizoctonia solani. The most likely explanation for fungal-induced shifts in the composition of rhizosphere bacteria is that bacteria are being selected which are successful in competing with fungi for root exudates. Based on the results we propose that measures increasing saprotrophic fungi in agricultural soils should be explored as an alternative approach to enhance natural biocontrol against soil-borne plant-pathogenic fungi, namely by stimulating indigenous antifungal rhizosphere bacteria. PMID:26393509

  3. Antifungal Rhizosphere Bacteria Can increase as Response to the Presence of Saprotrophic Fungi.

    PubMed

    de Boer, Wietse; Hundscheid, Maria P J; Klein Gunnewiek, Paulien J A; de Ridder-Duine, Annelies S; Thion, Cecile; van Veen, Johannes A; van der Wal, Annemieke

    2015-01-01

    Knowledge on the factors that determine the composition of bacterial communities in the vicinity of roots (rhizosphere) is essential to understand plant-soil interactions. Plant species identity, plant growth stage and soil properties have been indicated as major determinants of rhizosphere bacterial community composition. Here we show that the presence of saprotrophic fungi can be an additional factor steering rhizosphere bacterial community composition and functioning. We studied the impact of presence of two common fungal rhizosphere inhabitants (Mucor hiemalis and Trichoderma harzianum) on the composition of cultivable bacterial communities developing in the rhizosphere of Carex arenaria (sand sedge) in sand microcosms. Identification and phenotypic characterization of bacterial isolates revealed clear shifts in the rhizosphere bacterial community composition by the presence of two fungal strains (M. hiemalis BHB1 and T. harzianum PvdG2), whereas another M. hiemalis strain did not show this effect. Presence of both M. hiemalis BHB1 and T. harzianum PvdG2 resulted in a significant increase of chitinolytic and (in vitro) antifungal bacteria. The latter was most pronounced for M. hiemalis BHB1, an isolate from Carex roots, which stimulated the development of the bacterial genera Achromobacter and Stenotrophomonas. In vitro tests showed that these genera were strongly antagonistic against M. hiemalis but also against the plant-pathogenic fungus Rhizoctonia solani. The most likely explanation for fungal-induced shifts in the composition of rhizosphere bacteria is that bacteria are being selected which are successful in competing with fungi for root exudates. Based on the results we propose that measures increasing saprotrophic fungi in agricultural soils should be explored as an alternative approach to enhance natural biocontrol against soil-borne plant-pathogenic fungi, namely by stimulating indigenous antifungal rhizosphere bacteria.

  4. Antifungal Rhizosphere Bacteria Can increase as Response to the Presence of Saprotrophic Fungi

    PubMed Central

    de Boer, Wietse; Hundscheid, Maria P. J.; Klein Gunnewiek, Paulien J. A.; de Ridder-Duine, Annelies S.; Thion, Cecile; van Veen, Johannes A.; van der Wal, Annemieke

    2015-01-01

    Knowledge on the factors that determine the composition of bacterial communities in the vicinity of roots (rhizosphere) is essential to understand plant-soil interactions. Plant species identity, plant growth stage and soil properties have been indicated as major determinants of rhizosphere bacterial community composition. Here we show that the presence of saprotrophic fungi can be an additional factor steering rhizosphere bacterial community composition and functioning. We studied the impact of presence of two common fungal rhizosphere inhabitants (Mucor hiemalis and Trichoderma harzianum) on the composition of cultivable bacterial communities developing in the rhizosphere of Carex arenaria (sand sedge) in sand microcosms. Identification and phenotypic characterization of bacterial isolates revealed clear shifts in the rhizosphere bacterial community composition by the presence of two fungal strains (M. hiemalis BHB1 and T. harzianum PvdG2), whereas another M. hiemalis strain did not show this effect. Presence of both M. hiemalis BHB1 and T. harzianum PvdG2 resulted in a significant increase of chitinolytic and (in vitro) antifungal bacteria. The latter was most pronounced for M. hiemalis BHB1, an isolate from Carex roots, which stimulated the development of the bacterial genera Achromobacter and Stenotrophomonas. In vitro tests showed that these genera were strongly antagonistic against M. hiemalis but also against the plant-pathogenic fungus Rhizoctonia solani. The most likely explanation for fungal-induced shifts in the composition of rhizosphere bacteria is that bacteria are being selected which are successful in competing with fungi for root exudates. Based on the results we propose that measures increasing saprotrophic fungi in agricultural soils should be explored as an alternative approach to enhance natural biocontrol against soil-borne plant-pathogenic fungi, namely by stimulating indigenous antifungal rhizosphere bacteria. PMID:26393509

  5. Radiation analysis of the ITER pellet injection system

    SciTech Connect

    Gouge, M.J. ); Gomes, I.C.; Gomes, L.T.; Stevens, P.N, )

    1991-03-01

    The results of neutronics calculations for the pellet injection system of the International Thermonuclear Experimental Reactor (ITER) are described. Hands-on maintenance of components in the pellet injection room results in a considerable simplification of maintenance support equipment and in greater system availability. The basic configuration of the pellet injection system includes small-diameter guide tubes with which the pellet may have several small-angle collisions before reaching the plasma. The pellet injector port through which the guide tubes pass will be shared with ITER plasma diagnostics, so the calculation takes into account penetrations to accommodate numerous channels for a neutron spectrometer and neutron and gamma-ray cameras. The conservative assumption of steady-state operation of ITER for 1000 days was taken as the baseline for calculating the activation of components in the pellet injection room. The plasma configuration is based on the current ITER guidelines, the first wall configuration is based on the most recently updated configuration, and the blanket configuration is based on the US proposal for the blanket. The plasma, coils, and blanket regions were analyzed with the Monte Carlo code MCNP. The transport of neutrons through the penetrations was also performed with MCNP. The pellet injection room was modeled with the two-dimensional discrete ordinates code DORT, which was also used for the transport of neutrons during operation and of gamma rays caused by activation. The activation calculations were carried out with the REBATE code. Results from this study indicate that restricted personnel access to the pellet injection room is possible, so limited hands-on maintenance can be performed on the majority of the components in the room.

  6. 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.

  7. 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.

  8. 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.

  9. Design of a tritium pellet injector for TFTR

    SciTech Connect

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

    1991-01-01

    The TFTR tritium pellet injector (TPI) is designed to provide a tritium pellet fueling capability with pellet speeds in the 1{minus} to 3 km/s-range for the TFTR D-T phase. The existing TFTR deuterium pellet injector is being modified at Oak Ridge National Laboratory to provide a fourshot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns a two -stage light gas gun driver. The pipe gun concept has been qualified for tritium operation by the tritium proof-of-principle injector experiments conducted on the Tritium Systems Test Assembly at Los Alamos National Laboratory. In these experiments, tritium and D-T pellets were accelerated to speeds near 1.5 km/s. The TPI is being designed for pellet sizes in the range from 3.43 to 4.0 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 will be controlled by a programmable logic controller. 7 refs., 4 figs.

  10. 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.

  11. Key Formulation Variables in Tableting of Coated Pellets

    PubMed Central

    Murthy Dwibhashyam, V. S. N.; Ratna, J. Vijaya

    2008-01-01

    Multiple unit controlled release dosage forms offer various advantages over their single unit counterparts. Most of these advantages are associated with the uniform distribution of multiparticulates throughout the gastrointestinal tract. Though coated pellets can be filled into hard gelatin capsules, tablet formulation is the preferred one because of various advantages associated with it. However, compression of coated pellets is a challenging task necessitating the optimization of various formulation and process variables. The key formulation variables include composition, porosity, size, shape and density of the pellets; type and amount of polymer coating; nature, size and amount of tableting excipients. The pellet core should be strong with some degree of plasticity. It should be highly porous, small, with an irregular shape. The critical density to achieve prolonged release was reported to lie between 2.4 and 2.8 g/cm3. Acrylic polymer films are more flexible and more suitable for the coating of pellets to be compressed into tablets. Thicker coatings offer better resistance to frictional forces. Solvent based coatings are more flexible and have a higher degree of mechanical stability than the aqueous based ones. The tableting excipients should have cushioning property. They should not be significantly different in size and density from those of the pellet cores in order to avoid segregation. Addition of 30%-60% of tableting excipients is necessary to avoid any damage to the polymer coat and to retain its functional property. PMID:21394249

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. In vitro biocontrol analysis of Alternaria alternata (Fr.) Keissler under different environmental conditions.

    PubMed

    Sempere, F; Santamarina, M P

    2007-03-01

    The species Trichoderma harzianum was analyzed as possible biocontrol agent of Alternaria alternata under different environmental conditions (water activity and temperature). The strains were analyzed macroscopically to obtain the Index of Dominance. The analysis was completed using two microscopic techniques. T. harzianum showed dominance on contact over A. alternata at all testing temperatures and water activities tested except at 0.95 a(w) and 15 degrees C, at which T. harzianum inhibited A. alternata at a distance. Biocontrol was governed by different mechanisms such as competition for space and nutrients, mycoparasitism, and possible antibiosis. Temperature and water activity significantly influenced fungal growth rate. PMID:17356789

  17. Fengycin produced by Bacillus subtilis NCD-2 plays a major role in biocontrol of cotton seedling damping-off disease.

    PubMed

    Guo, Qinggang; Dong, Weixin; Li, Shezeng; Lu, Xiuyun; Wang, Peipei; Zhang, Xiaoyun; Wang, Ye; Ma, Ping

    2014-01-01

    Bacillus subtilis strain NCD-2 is strongly antagonistic toward phytopathogenic fungi, and functions as an excellent biocontrol agent for cotton soil-borne diseases. The aims of this study were to characterize the main active antifungal compound from strain NCD-2 and clarify its role in suppressing cotton damping-off disease. Strain NCD-2 and lipopeptide extract prepared from an NCD-2 culture strongly inhibited the growth of Rhizoctonia solani in vitro. The lipopeptides of strain NCD-2 were separated by fast protein liquid chromatography (FPLC) and the antifungal compound was identified as a cluster of fengycin homologs analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. A fengycin-deficient mutant was obtained by in-frame deletion of the fengycin synthetase gene in B. subtilis NCD-2. Compared with the wild-type strain, this mutant showed decreased abilities to inhibit the growth of R. solani in vitro and to suppress cotton damping-off disease in vivo. Studies showed that the population of fengycin-deficient mutant was almost same as that of the wild-type NCD-2 strain in the cotton rhizosphere. However, the population of R. solani in the cotton rhizosphere colonized by the fengycin-deficient mutant was twice that in the cotton rhizosphere colonized by the NCD-2 wild-type strain. This study demonstrated that fengycin-type lipopeptides are the main antifungal active compounds produced by B. subtilis NCD-2. These compounds play a major role in restricting the population of R. solani in the cotton rhizosphere and in suppressing cotton damping-off disease.

  18. Biocontrol of collar rot disease of betelvine (Piper betle L.) caused by Sclerotium rolfsii by using rhizosphere-competent Pseudomonas fluorescens NBRI-N6 and P. fluorescens NBRI-N.

    PubMed

    Singh, Anand; Mehta, Sangeeta; Singh, Harikesh Bahadur; Nautiyal, Chandra Shekhar

    2003-08-01

    Collar rot disease of betelvine (Piper betle L.) caused by Sclerotium rolfsii is difficult to control by conventional means by use of chemicals; therefore, use of biocontrol agents is desirable. In the present study, 186 bacterial strains of different morphological types were screened for their biocontrol activity against S. rolfsii under in vitro conditions. Two strains, Pseudomonas fluorescens NBRI-N6 and P. fluorescens NBRI-N, were selected for further studies because of their ability to inhibit the mycelial growth of the pathogen significantly. Spontaneous rifampicin-resistant (Rif) derivatives of P. fluorescens NBRI-N6 and P. fluorescens NBRI-N showing growth rate and membrane protein composition comparable to the wild type were selected to facilitate their monitoring in the rhizosphere. Field trials demonstrated that strain P. fluorescens NBRI-N6 was better than P. fluorescens NBRI-N in increasing the yield of betelvine significantly, whereas a consortium of the two strains controlled the disease more than either of the strains. The screening method should prove useful in identifying rhizosphere bacteria with the greatest potential for controlling diseases caused by phytopathogenic fungi. PMID:14506865

  19. Tick control: trapping, biocontrol, host management and other alternative strategies

    USGS Publications Warehouse

    Ginsberg, Howard S.; Edited by Sonenshine, Daniel E.; Roe, R. Michael

    2014-01-01

    Biology of Ticks is the most comprehensive work on tick biology and tick-borne diseases. This second edition is a multi-authored work, featuring the research and analyses of renowned experts across the globe. Spanning two volumes, the book examines the systematics, biology, structure, ecological adaptations, evolution, genomics and the molecular processes that underpin the growth, development and survival of these important disease-transmitting parasites. Also discussed is the remarkable array of diseases transmitted (or caused) by ticks, as well as modern methods for their control. This book should serve as a modern reference for students, scientists, physicians, veterinarians and other specialists. Volume I covers the biology of the tick and features chapters on tick systematics, tick life cycles, external and internal anatomy, and others dedicated to specific organ systems, specifically, the tick integument, mouthparts and digestive system, salivary glands, waste removal, salivary glands, respiratory system, circulatory system and hemolymph, fat body, the nervous and sensory systems and reproductive systems. Volume II includes chapters on the ecology of non-nidicolous and nidicolous ticks, genetics and genomics (including the genome of the Lyme disease vector Ixodes scapularis) and immunity, including host immune responses to tick feeding and tick-host interactions, as well as the tick's innate immune system that prevents and/or controls microbial infections. Six chapters cover in depth the many diseases caused by the major tick-borne pathogens, including tick-borne protozoa, viruses, rickettsiae of all types, other types of bacteria (e.g., the Lyme disease agent) and diseases related to tick paralytic agents and toxins. The remaining chapters are devoted to tick control using vaccines, acaricides, repellents, biocontrol, and, finally, techniques for breeding ticks in order to develop tick colonies for scientific study.

  20. Bio-Control of Salmonella Enteritidis in Foods Using Bacteriophages

    PubMed Central

    Bao, Hongduo; Zhang, Pengyu; Zhang, Hui; Zhou, Yan; Zhang, Lili; Wang, Ran

    2015-01-01

    Two lytic phages, vB_SenM-PA13076 (PA13076) and vB_SenM-PC2184 (PC2184), were isolated from chicken sewage and characterized with host strains Salmonella Enteritidis (SE) ATCC13076 and CVCC2184, respectively. Transmission electron microscopy revealed that they belonged to the family Myoviridae. The lytic abilities of these two phages in liquid culture showed 104 multiplicity of infection (MOI) was the best in inhibiting bacteria, with PC2184 exhibiting more activity than PA13076. The two phages exhibited broad host range within the genus Salmonella. Phage PA13076 and PC2184 had a lytic effect on 222 (71.4%) and 298 (95.8%) of the 311 epidemic Salmonella isolates, respectively. We tested the effectiveness of phage PA13076 and PC2184 as well as a cocktail combination of both in three different foods (chicken breast, pasteurized whole milk and Chinese cabbage) contaminated with SE. Samples were spiked with 1 × 104 CFU individual SE or a mixture of strains (ATCC13076 and CVCC2184), then treated with 1 × 108 PFU individual phage or a two phage cocktail, and incubated at 4 °C or 25 °C for 5 h. In general, the inhibitory effect of phage and phage cocktail was better at 4 °C than that at 25 °C, whereas the opposite result was observed in Chinese cabbage, and phage cocktail was better than either single phage. A significant reduction in bacterial numbers (1.5–4 log CFU/sample, p < 0.05) was observed in all tested foods. The two phages on the three food samples were relatively stable, especially at 4 °C, with the phages exhibiting the greatest stability in milk. Our research shows that our phages have potential effectiveness as a bio-control agent of Salmonella in foods. PMID:26305252

  1. Bacteriophage cocktail for biocontrol of Salmonella in dried pet food.

    PubMed

    Heyse, Serena; Hanna, Leigh Farris; Woolston, Joelle; Sulakvelidze, Alexander; Charbonneau, Duane

    2015-01-01

    Human salmonellosis has been associated with contaminated pet foods and treats. Therefore, there is interest in identifying novel approaches for reducing the risk of Salmonella contamination within pet food manufacturing environments. The use of lytic bacteriophages shows promise as a safe and effective way to mitigate Salmonella contamination in various food products. Bacteriophages are safe, natural, highly targeted antibacterial agents that specifically kill bacteria and can be targeted to kill food pathogens without affecting other microbiota. In this study, we show that a cocktail containing six bacteriophages had a broadspectrum activity in vitro against a library of 930 Salmonella enterica strains representing 44 known serovars. The cocktail was effective against 95% of the strains in this tested library. In liquid culture dose-ranging experiments, bacteriophage cocktail concentrations of ≥10(8) PFU/ml inactivated more than 90% of the Salmonella population (10(1) to 10(3) CFU/ml). Dried pet food inoculated with a mixture containing equal proportions of Salmonella serovars Enteritidis (ATCC 4931), Montevideo (ATCC 8387), Senftenberg (ATCC 8400), and Typhimurium (ATCC 13311) and then surface treated with the six-bacteriophage cocktail (≥2.5 ± 1.5 × 10(6) PFU/g) achieved a greater than 1-log (P < 0.001) reduction compared with the phosphate-buffered saline-treated control in measured viable Salmonella within 60 min. Moreover, this bacteriophage cocktail reduced natural contamination in samples taken from an undistributed lot of commercial dried dog food that tested positive for Salmonella. Our results indicate that bacteriophage biocontrol of S. enterica in dried pet food is technically feasible.

  2. Bio-Control of Salmonella Enteritidis in Foods Using Bacteriophages.

    PubMed

    Bao, Hongduo; Zhang, Pengyu; Zhang, Hui; Zhou, Yan; Zhang, Lili; Wang, Ran

    2015-08-24

    Two lytic phages, vB_SenM-PA13076 (PA13076) and vB_SenM-PC2184 (PC2184), were isolated from chicken sewage and characterized with host strains Salmonella Enteritidis (SE) ATCC13076 and CVCC2184, respectively. Transmission electron microscopy revealed that they belonged to the family Myoviridae. The lytic abilities of these two phages in liquid culture showed 104 multiplicity of infection (MOI) was the best in inhibiting bacteria, with PC2184 exhibiting more activity than PA13076. The two phages exhibited broad host range within the genus Salmonella. Phage PA13076 and PC2184 had a lytic effect on 222 (71.4%) and 298 (95.8%) of the 311 epidemic Salmonella isolates, respectively. We tested the effectiveness of phage PA13076 and PC2184 as well as a cocktail combination of both in three different foods (chicken breast, pasteurized whole milk and Chinese cabbage) contaminated with SE. Samples were spiked with 1 × 10(4) CFU individual SE or a mixture of strains (ATCC13076 and CVCC2184), then treated with 1 × 10(8) PFU individual phage or a two phage cocktail, and incubated at 4 °C or 25 °C for 5 h. In general, the inhibitory effect of phage and phage cocktail was better at 4 °C than that at 25 °C, whereas the opposite result was observed in Chinese cabbage, and phage cocktail was better than either single phage. A significant reduction in bacterial numbers (1.5-4 log CFU/sample, p < 0.05) was observed in all tested foods. The two phages on the three food samples were relatively stable, especially at 4 ºC, with the phages exhibiting the greatest stability in milk. Our research shows that our phages have potential effectiveness as a bio-control agent of Salmonella in foods.

  3. Bio-Control of Salmonella Enteritidis in Foods Using Bacteriophages.

    PubMed

    Bao, Hongduo; Zhang, Pengyu; Zhang, Hui; Zhou, Yan; Zhang, Lili; Wang, Ran

    2015-08-01

    Two lytic phages, vB_SenM-PA13076 (PA13076) and vB_SenM-PC2184 (PC2184), were isolated from chicken sewage and characterized with host strains Salmonella Enteritidis (SE) ATCC13076 and CVCC2184, respectively. Transmission electron microscopy revealed that they belonged to the family Myoviridae. The lytic abilities of these two phages in liquid culture showed 104 multiplicity of infection (MOI) was the best in inhibiting bacteria, with PC2184 exhibiting more activity than PA13076. The two phages exhibited broad host range within the genus Salmonella. Phage PA13076 and PC2184 had a lytic effect on 222 (71.4%) and 298 (95.8%) of the 311 epidemic Salmonella isolates, respectively. We tested the effectiveness of phage PA13076 and PC2184 as well as a cocktail combination of both in three different foods (chicken breast, pasteurized whole milk and Chinese cabbage) contaminated with SE. Samples were spiked with 1 × 10(4) CFU individual SE or a mixture of strains (ATCC13076 and CVCC2184), then treated with 1 × 10(8) PFU individual phage or a two phage cocktail, and incubated at 4 °C or 25 °C for 5 h. In general, the inhibitory effect of phage and phage cocktail was better at 4 °C than that at 25 °C, whereas the opposite result was observed in Chinese cabbage, and phage cocktail was better than either single phage. A significant reduction in bacterial numbers (1.5-4 log CFU/sample, p < 0.05) was observed in all tested foods. The two phages on the three food samples were relatively stable, especially at 4 ºC, with the phages exhibiting the greatest stability in milk. Our research shows that our phages have potential effectiveness as a bio-control agent of Salmonella in foods. PMID:26305252

  4. 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

  5. Use of a non-homologous end-joining-deficient strain (delta-ku70) of the biocontrol fungus Trichoderma virens to investigate the function of the laccase gene lcc1 in sclerotia degradation

    PubMed Central

    Catalano, Valentina; Vergara, Mariarosaria; Hauzenberger, Jasmin R.; Seiboth, Bernhard; Sarrocco, Sabrina; Vannacci, Giovanni; Kubicek, Christian P.

    2010-01-01

    The aim of this study was to apply a generated Δtku70 strain with increased homologous recombination efficiency from the mycoparasitic fungus Trichoderma virens for studying the involvement of laccases in the degradation of sclerotia of plant pathogenic fungi. Inactivation of the non-homologous end-joining pathway has become a successful tool in filamentous fungi to overcome poor targeting efficiencies for genetic engineering. Here, we applied this principle to the biocontrol fungus T. virens, strain I10, by deleting its tku70 gene. This strain was subsequently used to delete the laccase gene lcc1, which we found to be expressed after interaction of T. virens with sclerotia of the plant pathogenic fungi Botrytis cinerea and Sclerotinia sclerotiorum. Lcc1 was strongly upregulated at early colonization of B. cinerea sclerotia and steadily induced during colonization of S. sclerotiorum sclerotia. The Δtku70Δlcc1 mutant was altered in its ability to degrade the sclerotia of B. cinerea and S. sclerotiorum. Interestingly, while the decaying ability for B. cinerea sclerotia was significantly decreased, that to degrade S. sclerotiorum sclerotia was even enhanced, suggesting the operation of different mechanisms in the mycoparasitism of these two types of sclerotia by the laccase LCC1. PMID:20872221

  6. Use of a non-homologous end-joining-deficient strain (delta-ku70) of the biocontrol fungus Trichoderma virens to investigate the function of the laccase gene lcc1 in sclerotia degradation.

    PubMed

    Catalano, Valentina; Vergara, Mariarosaria; Hauzenberger, Jasmin R; Seiboth, Bernhard; Sarrocco, Sabrina; Vannacci, Giovanni; Kubicek, Christian P; Seidl-Seiboth, Verena

    2011-02-01

    The aim of this study was to apply a generated Δtku70 strain with increased homologous recombination efficiency from the mycoparasitic fungus Trichoderma virens for studying the involvement of laccases in the degradation of sclerotia of plant pathogenic fungi. Inactivation of the non-homologous end-joining pathway has become a successful tool in filamentous fungi to overcome poor targeting efficiencies for genetic engineering. Here, we applied this principle to the biocontrol fungus T. virens, strain I10, by deleting its tku70 gene. This strain was subsequently used to delete the laccase gene lcc1, which we found to be expressed after interaction of T. virens with sclerotia of the plant pathogenic fungi Botrytis cinerea and Sclerotinia sclerotiorum. Lcc1 was strongly upregulated at early colonization of B. cinerea sclerotia and steadily induced during colonization of S. sclerotiorum sclerotia. The Δtku70Δlcc1 mutant was altered in its ability to degrade the sclerotia of B. cinerea and S. sclerotiorum. Interestingly, while the decaying ability for B. cinerea sclerotia was significantly decreased, that to degrade S. sclerotiorum sclerotia was even enhanced, suggesting the operation of different mechanisms in the mycoparasitism of these two types of sclerotia by the laccase LCC1. PMID:20872221

  7. Marine Fungi: Their Ecology and Molecular Diversity

    NASA Astrophysics Data System (ADS)

    Richards, Thomas A.; Jones, Meredith D. M.; Leonard, Guy; Bass, David

    2012-01-01

    Fungi appear to be rare in marine environments. There are relatively few marine isolates in culture, and fungal small subunit ribosomal DNA (SSU rDNA) sequences are rarely recovered in marine clone library experiments (i.e., culture-independent sequence surveys of eukaryotic microbial diversity from environmental DNA samples). To explore the diversity of marine fungi, we took a broad selection of SSU rDNA data sets and calculated a summary phylogeny. Bringing these data together identified a diverse collection of marine fungi, including sequences branching close to chytrids (flagellated fungi), filamentous hypha-forming fungi, and multicellular fungi. However, the majority of the sequences branched with ascomycete and basidiomycete yeasts. We discuss evidence for 36 novel marine lineages, the majority and most divergent of which branch with the chytrids. We then investigate what these data mean for the evolutionary history of the Fungi and specifically marine-terrestrial transitions. Finally, we discuss the roles of fungi in marine ecosystems.

  8. Wood-rotting fungi of North America

    SciTech Connect

    Gilbertson, R.L.

    1980-01-01

    The biology of wood-rotting fungi is reviewed. Discussions are presented in taxonomy, species diversity, North American distribution, developmental response to environmental factors, edibility and toxicity, medical uses, relationships of fungi with insects and birds, the role of fungi as mycorrhiza, pathological relationships with trees, role in wood decay, and ecology. Threats to the continuing existence of these fungi as a result of increased utilization of wood as fuel are also discussed. (ACR)

  9. [Alternative oxidase in industrial fungi].

    PubMed

    Gu, Shuai; Liu, Qiang; He, Hao; Li, Shuang

    2015-01-01

    Filamentous fungi have been used in industrial fermentation extensively. Based on non-phosphorylating electron transport process, alternative respiration pathway (ARP) acts as an energy overflow, which can balance carbon metabolism and electron transport, allow the continuance of tricarboxylic acid cycle without the formation of ATP, and permit the turnover of carbon skeletons. Alternative respiration pathway also plays an important role in the stress response of fungi and the physiological function of conditioned pathogen. Alternative oxidase (AOX) is the terminal oxidase responsible for the activity of alternative respiration pathway, which exists widely in higher plants, parts of fungi and algae. Owing to the property that alternative oxidase (AOX) is sensitive to salicylhydroxamic acid (SHAM) and insensitive to conventional inhibitors of cytochrome respiration, alternative respiration pathway by AOX is also named as cyanide-resistant respiration (CRR). In recent years, the study of the alternative respiration pathway and alternative oxidase has been a hot topic in the area involving cellular respiration metabolism. In this review we summarized the latest research advances about the functions of alternative respiration pathway and alternative oxidase in industrial fungi.

  10. Airborne fungi--a resurvey

    SciTech Connect

    Meyer, G.H.; Prince, H.E.; Raymer, W.J.

    1983-07-01

    A 15-month survey of airborne fungi at 14 geographical stations was conducted to determine the incidence of different fungal genera. Five of these stations were surveyed 25 years earlier. A comparison between previous studies and present surveys revealed similar organisms at each station with slight shifts in frequency of dominant genera.

  11. 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%.

  12. 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

  13. Cytokinin production by Pseudomonas fluorescens G20-18 determines biocontrol activity against Pseudomonas syringae in Arabidopsis

    PubMed Central

    Großkinsky, Dominik K.; Tafner, Richard; Moreno, María V.; Stenglein, Sebastian A.; García de Salamone, Inés E.; Nelson, Louise M.; Novák, Ondřej; Strnad, Miroslav; van der Graaff, Eric; Roitsch, Thomas

    2016-01-01

    Plant beneficial microbes mediate biocontrol of diseases by interfering with pathogens or via strengthening the host. Although phytohormones, including cytokinins, are known to regulate plant development and physiology as well as plant immunity, their production by microorganisms has not been considered as a biocontrol mechanism. Here we identify the ability of Pseudomonas fluorescens G20-18 to efficiently control P. syringae infection in Arabidopsis, allowing maintenance of tissue integrity and ultimately biomass yield. Microbial cytokinin production was identified as a key determinant for this biocontrol effect on the hemibiotrophic bacterial pathogen. While cytokinin-deficient loss-of-function mutants of G20-18 exhibit impaired biocontrol, functional complementation with cytokinin biosynthetic genes restores cytokinin-mediated biocontrol, which is correlated with differential cytokinin levels in planta. Arabidopsis mutant analyses revealed the necessity of functional plant cytokinin perception and salicylic acid-dependent defence signalling for this biocontrol mechanism. These results demonstrate microbial cytokinin production as a novel microbe-based, hormone-mediated concept of biocontrol. This mechanism provides a basis to potentially develop novel, integrated plant protection strategies combining promotion of growth, a favourable physiological status and activation of fine-tuned direct defence and abiotic stress resilience. PMID:26984671

  14. Cytokinin production by Pseudomonas fluorescens G20-18 determines biocontrol activity against Pseudomonas syringae in Arabidopsis.

    PubMed

    Großkinsky, Dominik K; Tafner, Richard; Moreno, María V; Stenglein, Sebastian A; García de Salamone, Inés E; Nelson, Louise M; Novák, Ondřej; Strnad, Miroslav; van der Graaff, Eric; Roitsch, Thomas

    2016-01-01

    Plant beneficial microbes mediate biocontrol of diseases by interfering with pathogens or via strengthening the host. Although phytohormones, including cytokinins, are known to regulate plant development and physiology as well as plant immunity, their production by microorganisms has not been considered as a biocontrol mechanism. Here we identify the ability of Pseudomonas fluorescens G20-18 to efficiently control P. syringae infection in Arabidopsis, allowing maintenance of tissue integrity and ultimately biomass yield. Microbial cytokinin production was identified as a key determinant for this biocontrol effect on the hemibiotrophic bacterial pathogen. While cytokinin-deficient loss-of-function mutants of G20-18 exhibit impaired biocontrol, functional complementation with cytokinin biosynthetic genes restores cytokinin-mediated biocontrol, which is correlated with differential cytokinin levels in planta. Arabidopsis mutant analyses revealed the necessity of functional plant cytokinin perception and salicylic acid-dependent defence signalling for this biocontrol mechanism. These results demonstrate microbial cytokinin production as a novel microbe-based, hormone-mediated concept of biocontrol. This mechanism provides a basis to potentially develop novel, integrated plant protection strategies combining promotion of growth, a favourable physiological status and activation of fine-tuned direct defence and abiotic stress resilience. PMID:26984671

  15. 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.

  16. 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.

  17. 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. PMID:26248144

  18. Pseudomonas fluorescens F113 mutant with enhanced competitive colonization ability and improved biocontrol activity against fungal root pathogens.

    PubMed

    Barahona, Emma; Navazo, Ana; Martínez-Granero, Francisco; Zea-Bonilla, Teresa; Pérez-Jiménez, Rosa María; Martín, Marta; Rivilla, Rafael

    2011-08-01

    Motility is one of the most important traits for efficient rhizosphere colonization by Pseudomonas fluorescens F113rif (F113). In this bacterium, motility is a polygenic trait that is repressed by at least three independent pathways, including the Gac posttranscriptional system, the Wsp chemotaxis-like pathway, and the SadB pathway. Here we show that the kinB gene, which encodes a signal transduction protein that together with AlgB has been implicated in alginate production, participates in swimming motility repression through the Gac pathway, acting downstream of the GacAS two-component system. Gac mutants are impaired in secondary metabolite production and are unsuitable as biocontrol agents. However, the kinB mutant and a triple mutant affected in kinB, sadB, and wspR (KSW) possess a wild-type phenotype for secondary metabolism. The KSW strain is hypermotile and more competitive for rhizosphere colonization than the wild-type strain. We have compared the biocontrol activity of KSW with those of the wild-type strain and a phenotypic variant (F113v35 [V35]) which is hypermotile and hypercompetitive but is affected in secondary metabolism since it harbors a gacS mutation. Biocontrol experiments in the Fusarium oxysporum f. sp. radicis-lycopersici/Lycopersicum esculentum (tomato) and Phytophthora cactorum/Fragaria vesca (strawberry) pathosystems have shown that the three strains possess biocontrol activity. Biocontrol activity was consistently lower for V35, indicating that the production of secondary metabolites was the most important trait for biocontrol. Strain KSW showed improved biocontrol compared with the wild-type strain, indicating that an increase in competitive colonization ability resulted in improved biocontrol and that the rational design of biocontrol agents by mutation is feasible. PMID:21685161

  19. Morphology of Filamentous Fungi: Linking Cellular Biology to Process Engineering Using Aspergillus niger

    NASA Astrophysics Data System (ADS)

    Krull, Rainer; Cordes, Christiana; Horn, Harald; Kampen, Ingo; Kwade, Arno; Neu, Thomas R.; Nörtemann, Bernd

    In various biotechnological processes, filamentous fungi, e.g. Aspergillus niger, are widely applied for the production of high value-added products due to their secretion efficiency. There is, however, a tangled relationship between the morphology of these microorganisms, the transport phenomena and the related productivity. The morphological characteristics vary between freely dispersed mycelia and distinct pellets of aggregated biomass. Hence, advantages and disadvantages for mycel or pellet cultivation have to be balanced out carefully. Due to this inadequate understanding of morphogenesis of filamentous microorganisms, fungal morphology, along with reproducibility of inocula of the same quality, is often a bottleneck of productivity in industrial production. To obtain an optimisation of the production process it is of great importance to gain a better understanding of the molecular and cell biology of these microorganisms as well as the approaches in biochemical engineering and particle technique, in particular to characterise the interactions between the growth conditions, cell morphology, spore-hyphae-interactions and product formation. Advances in particle and image analysis techniques as well as micromechanical devices and their applications to fungal cultivations have made available quantitative morphological data on filamentous cells. This chapter provides the ambitious aspects of this line of action, focussing on the control and characterisation of the morphology, the transport gradients and the approaches to understand the metabolism of filamentous fungi. Based on these data, bottlenecks in the morphogenesis of A. niger within the complex production pathways from gene to product should be identified and this may improve the production yield.

  20. Chemosensitization of plant pathogenic fungi to agricultural fungicides.

    PubMed

    Dzhavakhiya, Vitaly; Shcherbakova, Larisa; Semina, Yulia; Zhemchuzhina, Natalia; Campbell, Bruce

    2012-01-01

    A common consequence of using agricultural fungicides is the development of resistance by fungal pathogens, which undermines reliability of fungicidal effectiveness. A potentially new strategy to aid in overcoming or minimizing this problem is enhancement of pathogen sensitivity to fungicides, or "chemosensitization." Chemosensitization can be accomplished by combining a commercial fungicide with a certain non- or marginally fungicidal substance at levels where, alone, neither compound would be effective. Chemosensitization decreases the probability of the pathogen developing resistance, reduces the toxic impact on the environment by lowering effective dosage levels of toxic fungicides, and improves efficacy of antifungal agents. The present study shows that the antifungal activity of azole and strobilurin fungicides can be significantly enhanced through their co-application with certain natural or synthetic products against several economically important plant pathogenic fungi. Quadris (azoxystrobin) combined with thymol at a non-fungitoxic concentration produced much higher growth inhibition of Bipolaris sorokiniana, Phoma glomerata, Alternaria sp. and Stagonospora nodorum than the fungicide alone. The effect of Dividend (difenoconazole) applied with thymol significantly enhanced antifungal activity against B. sorokiniana and S. nodorum. Folicur (tebuconazole) combined with 4-hydroxybenzaldehyde (4-HBA), 2,3-dihydroxybenzaldehyde or thymol significantly inhibited growth of Alternaria alternata, at a much greater level than the fungicide alone. In addition, co-application of Folicur and 4-HBA resulted in a similar enhancement of antifungal activity against Fusarium culmorum. Lastly, we discovered that metabolites in the culture liquid of Fusarium sambucinum biocontrol isolate FS-94 also had chemosensitizing activity, increasing S. nodorum sensitivity to Folicur and Dividend. PMID:22408641

  1. Chemosensitization of Plant Pathogenic Fungi to Agricultural Fungicides

    PubMed Central

    Dzhavakhiya, Vitaly; Shcherbakova, Larisa; Semina, Yulia; Zhemchuzhina, Natalia; Campbell, Bruce

    2012-01-01

    A common consequence of using agricultural fungicides is the development of resistance by fungal pathogens, which undermines reliability of fungicidal effectiveness. A potentially new strategy to aid in overcoming or minimizing this problem is enhancement of pathogen sensitivity to fungicides, or “chemosensitization.” Chemosensitization can be accomplished by combining a commercial fungicide with a certain non- or marginally fungicidal substance at levels where, alone, neither compound would be effective. Chemosensitization decreases the probability of the pathogen developing resistance, reduces the toxic impact on the environment by lowering effective dosage levels of toxic fungicides, and improves efficacy of antifungal agents. The present study shows that the antifungal activity of azole and strobilurin fungicides can be significantly enhanced through their co-application with certain natural or synthetic products against several economically important plant pathogenic fungi. Quadris (azoxystrobin) combined with thymol at a non-fungitoxic concentration produced much higher growth inhibition of Bipolaris sorokiniana, Phoma glomerata, Alternaria sp. and Stagonospora nodorum than the fungicide alone. The effect of Dividend (difenoconazole) applied with thymol significantly enhanced antifungal activity against B. sorokiniana and S. nodorum. Folicur (tebuconazole) combined with 4-hydroxybenzaldehyde (4-HBA), 2,3-dihydroxybenzaldehyde or thymol significantly inhibited growth of Alternaria alternata, at a much greater level than the fungicide alone. In addition, co-application of Folicur and 4-HBA resulted in a similar enhancement of antifungal activity against Fusarium culmorum. Lastly, we discovered that metabolites in the culture liquid of Fusarium sambucinum biocontrol isolate FS-94 also had chemosensitizing activity, increasing S. nodorum sensitivity to Folicur and Dividend. PMID:22408641

  2. Chemosensitization of plant pathogenic fungi to agricultural fungicides.

    PubMed

    Dzhavakhiya, Vitaly; Shcherbakova, Larisa; Semina, Yulia; Zhemchuzhina, Natalia; Campbell, Bruce

    2012-01-01

    A common consequence of using agricultural fungicides is the development of resistance by fungal pathogens, which undermines reliability of fungicidal effectiveness. A potentially new strategy to aid in overcoming or minimizing this problem is enhancement of pathogen sensitivity to fungicides, or "chemosensitization." Chemosensitization can be accomplished by combining a commercial fungicide with a certain non- or marginally fungicidal substance at levels where, alone, neither compound would be effective. Chemosensitization decreases the probability of the pathogen developing resistance, reduces the toxic impact on the environment by lowering effective dosage levels of toxic fungicides, and improves efficacy of antifungal agents. The present study shows that the antifungal activity of azole and strobilurin fungicides can be significantly enhanced through their co-application with certain natural or synthetic products against several economically important plant pathogenic fungi. Quadris (azoxystrobin) combined with thymol at a non-fungitoxic concentration produced much higher growth inhibition of Bipolaris sorokiniana, Phoma glomerata, Alternaria sp. and Stagonospora nodorum than the fungicide alone. The effect of Dividend (difenoconazole) applied with thymol significantly enhanced antifungal activity against B. sorokiniana and S. nodorum. Folicur (tebuconazole) combined with 4-hydroxybenzaldehyde (4-HBA), 2,3-dihydroxybenzaldehyde or thymol significantly inhibited growth of Alternaria alternata, at a much greater level than the fungicide alone. In addition, co-application of Folicur and 4-HBA resulted in a similar enhancement of antifungal activity against Fusarium culmorum. Lastly, we discovered that metabolites in the culture liquid of Fusarium sambucinum biocontrol isolate FS-94 also had chemosensitizing activity, increasing S. nodorum sensitivity to Folicur and Dividend.

  3. [Correction of autonomic reactions parameters in organism of cosmonaut with adaptive biocontrol method

    NASA Technical Reports Server (NTRS)

    Kornilova, L. N.; Cowings, P. S.; Toscano, W. B.; Arlashchenko, N. I.; Korneev, D. Iu; Ponomarenko, A. V.; Salagovich, S. V.; Sarantseva, A. V.; Kozlovskaia, I. B.

    2000-01-01

    Presented are results of testing the method of adaptive biocontrol during preflight training of cosmonauts. Within the MIR-25 crew, a high level of controllability of the autonomous reactions was characteristic of Flight Commanders MIR-23 and MIR-25 and flight Engineer MIR-23, while Flight Engineer MIR-25 displayed a weak intricate dependence of these reactions on the depth of relaxation or strain.

  4. What magnitude are observed non-target impacts from weed biocontrol?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A systematic review focused by plant on non-target impacts from agents deliberately introduced for the biological control of weeds found significant non-target impacts to be rare. The magnitude of direct impact of 43 biocontrol agents on 140 non-target plants was retrospectively categorized using a ...

  5. Yeast Biocontrol of a Fungal Plant Disease: A Model for Studying Organism Interrelationships

    ERIC Educational Resources Information Center

    Chanchaichaovivat, Arun; Panijpan, Bhinyo; Ruenwongsa, Pintip

    2008-01-01

    An experiment on the action of the yeast, "Saccharomyces cerevisiae", against a fungal plant disease is proposed for secondary students (Grade 11) to support their study of organism interrelationship. This biocontrol experiment serves as the basis for discussing relationships among three organisms (red chilli fruit, "Saccharomyces cerevisiae," and…

  6. Draft Genome Sequence of the Commercial Biocontrol Strain Pantoea agglomerans P10c

    PubMed Central

    Rezzonico, Fabio; Blom, Jochen; Goesmann, Alexander; Abelli, Azzurra; Kron Morelli, Roberto; Vanneste, Joël L.; Duffy, Brion

    2015-01-01

    We report here the draft genome sequence of the biocontrol strain Pantoea agglomerans P10c, composed of a draft chromosome and two plasmids: the 559-kb large Pantoea plasmid 1 (pPag3) and a 182-kb plasmid (pPag1). A genomic island containing pantocin A biosynthesis genes was identified. PMID:26659685

  7. Draft Whole-Genome Sequence of the Biocontrol Agent Trichoderma harzianum T6776.

    PubMed

    Baroncelli, Riccardo; Piaggeschi, Giulia; Fiorini, Lisa; Bertolini, Edoardo; Zapparata, Antonio; Pè, Mario Enrico; Sarrocco, Sabrina; Vannacci, Giovanni

    2015-01-01

    Trichoderma harzianum T6776 is a promising beneficial isolate whose effects consist of growth promotion, positive response of photosynthetic activity, hormonal signaling, and carbon partitioning in tomato, coupled with biocontrol of plant pathogens. Here, we present the first genome assembly of T6776, providing a useful platform for the scientific community. PMID:26067977

  8. Stress tolerance and biocontrol performance of the yeast antagonist, Candida diversa, change with morphology transition.

    PubMed

    Li, Guangkun; Chi, Mengshan; Chen, Huizhen; Sui, Yuan; Li, Yan; Liu, Yongsheng; Zhang, Xiaojing; Sun, Zhiqiang; Liu, Guoqing; Wang, Qi; Liu, Jia

    2016-02-01

    As an eco-friendly management method, biological control of postharvest diseases, utilizing antagonistic yeasts, is a research topic receiving considerable attention. Detailed knowledge on the biology of yeast antagonists is crucial when considering their potential application and development as biocontrol products. Changes in the growth form, such as single-cell to pseudohyphae, have been associated with the mode of action in postharvest biocontrol yeasts. In this study, the antagonistic yeast, Candida diversa, reversibly shifted from a single-cell morphology on yeast peptone dextrose (YPD) medium with 2 % agar to a pseudohyphal morphology on YPD with 0.3 % agar. The tolerance of the pseudohyphal form to heat and oxidative stresses, as well as the biocontrol efficacy against Botrytis cinerea on apple and kiwifruit stored at 25 and 4 °C, was significantly higher as compared to the single-cell form. This study provides new information on the ability of C. diversa to change its morphology and the impact of the morphology shift on stress tolerance and biocontrol performance. PMID:26637302

  9. Agar composition affects in vitro screening of biocontrol activity of antagonistic microorganisms.

    PubMed

    Bosmans, L; De Bruijn, I; De Mot, R; Rediers, H; Lievens, B

    2016-08-01

    Agar-based screening assays are the method of choice when evaluating antagonistic potential of bacterial biocontrol-candidates against pathogens. We showed that when using the same medium, but different agar compositions, the activity of a bacterial antagonist against Agrobacterium was strongly affected. Consequently, results from in vitro screenings should be interpreted cautiously. PMID:27166668

  10. Testing the efficacy of eGFP-transformed Aspergillus flavus as biocontrol strains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current biological control methods to prevent pre-harvest aflatoxin contamination of corn, cottonseed, and ground and tree nuts involve field inoculation of non-aflatoxigenic Aspergillus flavus. To date, the efficacy of this approach requires annual reapplication of the biocontrol agent. The reason ...

  11. Identification of Biocontrol Agents to Control the Fungal Pathogen, Geomyces destructans, in Bats

    NASA Astrophysics Data System (ADS)

    Braunstein, S.; Cheng, T.

    2013-12-01

    The fungal pathogen Geomyces destructans (Gd) causes the disease White-nose Syndrome (WNS) in bats and is estimated to have killed millions of bats since its emergence in North America in 2006. Gd is predicted to cause the local extinction of at least three bat species if rates of decline continue unabated. Given the devastating impacts of Gd to bat populations, identifying a viable method for controlling the pathogen is pertinent for conservation of affected bat species. Our work focuses on identifying naturally-occurring skin bacteria on bats that are antagonistic to Gd that could potentially be used as a biocontrol. We cultured bacteria from skin swabs taken from wild bats (Myotis lucifugus, Eptesicus fuscus, Myotis sodalis, Perimyotis subflavus). We conducted challenge experiments to identify bacterial strains that inhibited Gd growth. Bacteria that exhibited antifungal properties were identified using 16S and gyrB markers. Our methods identified several bacteria in the Pseudomonas fluorescens complex as potential biocontrol agents. Future work will continue to test the viability of these bacteria as biocontrol agents via experimental treatments with live captive bats. The failure of previous non-biocontrol methods highlights the importance of developing these bacteria as a biologically-friendly method for controlling Gd. A bat infected with Geomyces destructans. Photo by West Virginia Division of Natural Resources Bacterial culture from the swab of a bat's wings

  12. Draft Whole-Genome Sequence of the Biocontrol Agent Trichoderma harzianum T6776.

    PubMed

    Baroncelli, Riccardo; Piaggeschi, Giulia; Fiorini, Lisa; Bertolini, Edoardo; Zapparata, Antonio; Pè, Mario Enrico; Sarrocco, Sabrina; Vannacci, Giovanni

    2015-06-11

    Trichoderma harzianum T6776 is a promising beneficial isolate whose effects consist of growth promotion, positive response of photosynthetic activity, hormonal signaling, and carbon partitioning in tomato, coupled with biocontrol of plant pathogens. Here, we present the first genome assembly of T6776, providing a useful platform for the scientific community.

  13. Biocontrol potential of endophytes harbored in Radula marginata (liverwort) from the New Zealand ecosystem.

    PubMed

    Kusari, Parijat; Kusari, Souvik; Spiteller, Michael; Kayser, Oliver

    2014-10-01

    Radula marginata and Cannabis sativa L. are two phylogenetically unrelated plant species containing structurally similar secondary metabolites like cannabinoids. The major objective of our work was the isolation, identification, biocontrol efficacies, biofilm forming potential and anti-biofilm ability of endophytic microbial community of the liverwort R. marginata, as compared to bacterial endophytic isolates harbored in C. sativa plants. A total of 15 endophytic fungal and 4 endophytic bacterial isolates were identified, including the presence of a bacterial endosymbiont within an endophytic fungal isolate. The endosymbiont was visible only when the fungus containing it was challenged with two phytopathogens Botrytis cinerea and Trichothecium roseum, highlighting a tripartite microbe-microbe interaction and biocontrol potency of endophytes under biotic stress. We also observed sixteen types of endophytic fungal-pathogen and twelve types of endophytic bacterial-pathogen interactions coupled to varying degree of growth inhibitions of either the pathogen or endophyte or both. This showed the magnitude of biocontrol efficacies of endophytes in aiding plant fitness benefits under different media (environmental) conditions. Additionally, it was ecologically noteworthy to find the presence of similar endophytic bacterial genera in both Radula and Cannabis plants, which exhibited similar functional traits like biofilm formation and general anti-biofilm activities. Thus far, our work underlines the biocontrol potency and defensive functional traits (in terms of antagonism and biofilm formation) of endophytes harbored in liverwort R. marginata as compared to the endophytic community of phylogenetically unrelated but phytochemically similar plant C. sativa. PMID:25100187

  14. Antagonistic activity of Bacillus subtilis SB1 and its biocontrol effect on tomato bacterial wilt

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A potential biocontrol agent of bacterial wilt, Bacillus subtilis SB1, isolated from tomato roots, showed a broad-spectrum of antimicrobial activity in in vitro experiments. It inhibited the growth of many plant pathogens, including Ralstonia solanacearum, Xanthomonas oryzae pv. oryzae, Fusarium ox...

  15. Efficacy of water dispersible formulations of biocontrol strains of Aspergillus flavus for aflatoxin management in corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field experiments were conducted in 2011 and 2012 to evaluate the efficacy of water dispersible granule (WDG) formulations of biocontrol strains of Aspergillus flavus in controlling aflatoxin contamination of corn. In 2011, when aflatoxin was present at very high levels, no WDG treatment provided s...

  16. Stress tolerance and biocontrol performance of the yeast antagonist, Candida diversa, change with morphology transition.

    PubMed

    Li, Guangkun; Chi, Mengshan; Chen, Huizhen; Sui, Yuan; Li, Yan; Liu, Yongsheng; Zhang, Xiaojing; Sun, Zhiqiang; Liu, Guoqing; Wang, Qi; Liu, Jia

    2016-02-01

    As an eco-friendly management method, biological control of postharvest diseases, utilizing antagonistic yeasts, is a research topic receiving considerable attention. Detailed knowledge on the biology of yeast antagonists is crucial when considering their potential application and development as biocontrol products. Changes in the growth form, such as single-cell to pseudohyphae, have been associated with the mode of action in postharvest biocontrol yeasts. In this study, the antagonistic yeast, Candida diversa, reversibly shifted from a single-cell morphology on yeast peptone dextrose (YPD) medium with 2 % agar to a pseudohyphal morphology on YPD with 0.3 % agar. The tolerance of the pseudohyphal form to heat and oxidative stresses, as well as the biocontrol efficacy against Botrytis cinerea on apple and kiwifruit stored at 25 and 4 °C, was significantly higher as compared to the single-cell form. This study provides new information on the ability of C. diversa to change its morphology and the impact of the morphology shift on stress tolerance and biocontrol performance.

  17. Genomic Diversity of Biocontrol Strains of Pseudomonas spp. Isolated from Aerial or Root Surfaces of Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The striking ecological, metabolic, and biochemical diversity of Pseudomonas has intrigued microbiologists for many decades. To explore the genomic diversity of biocontrol strains of Pseudomonas spp., we derived high quality draft sequences of seven strains known to suppress plant disease. The str...

  18. Draft genome sequences of the Pseudomonas fluorescens biocontrol strains Wayne1R and Wood1R.

    PubMed

    Rong, Xiaoqing; Gurel, Fulya Baysal; Meulia, Tea; McSpadden Gardener, Brian B

    2012-02-01

    Pseudomonas fluorescens strains Wayne1R and Wood1R have proven capacities to improve plant health. Here we report the draft genome sequences and automatic annotations of both strains. Genome comparisons reveal similarities with P. fluorescens strain Pf-5, reveal the novelty of Wood1R, and indicate some genes that may be related to biocontrol.

  19. Pantoea applied genomics to understand and improve biocontrol activity against fire blight

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pantoea agglomerans and P. vagans (ex. Erwinia herbicola) are common epiphytes of pome fruit flowers and three strains (E325, P10c, C9-1) have been commercially developed as effective biocontrol products for managing fire blight (Erwinia amylovora). Antibiotics as a standard, reliable chemical optio...

  20. Heat shock improves stress tolerance and biocontrol performance of Rhodotorula mucilaginosa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biological control of postharvest diseases, utilizing wild species and strains of antagonistic yeasts, is a research topic and eco-friendly management approach that has received considerable attention. A few yeast-based biocontrol products are available in the market. Ecological fitness, stress to...

  1. Biocontrol attack exacerbates pollen-limitation in the invasive plant Centaurea solstitialis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pollen-limited seed set is rarely studied in invasive plants despite the fact that >50% of the most problematic invaders in North America are pollinator-dependent. Further, pollinators are rarely considered in the use biocontrol agents to manage invaders. The ecological literature shows that herbivo...

  2. Controlling filamentous fungi morphology with microparticles to enhanced β-mannanase production.

    PubMed

    Yatmaz, Ercan; Karahalil, Ercan; Germec, Mustafa; Ilgin, Merve; Turhan, İrfan

    2016-09-01

    β-mannanase was produced mainly by Aspergillus species and can degrade the β-1,4-mannose linkages of galactomannans. This study was undertaken to enhance mannanase production using talcum and aluminum oxide as the microparticles, which control cell morphology of recombinant Aspergillus sojae in glucose and carob extract medium. Both microparticles improved fungal growth in glucose and carob pod extract medium. Aluminum oxide (1 g/L) was the best agent for glucose medium which resulted in 514.0 U/ml. However, the highest mannanase activity was found as 568.7 U/ml with 5 g/L of talcum in carob extract medium. Increase in microparticle concentration resulted in decreasing the pellet size diameter. Furthermore, more than 10 g/L of talcum addition changed the filamentous fungi growth type from pellet to pellet/mycelium mixture. Results showed that right type and concentration of microparticle in fermentation media improved the mannanase activity and production rate by controlling the growth morphology. PMID:27129457

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

    SciTech Connect

    Jha, M.C.; Blandon, A.E.; Hepworth, M.T.

    1988-03-22

    A durable, pelletized and indurated sorbent for removing hydrogen sulfide from hot coal gas is described which consists essentially of zinc ferrite, has a surface area of about 0.5 to about 5 m./sup 2/gram, and is prepared by mixing fine iron oxide and fine zinc oxide, each having a particle size of less than about 1 micron in substantially equi-molar amounts with an inorganic binder in an amount greater than zero and up to about 15%, by weight, and an organic binder in an amount greater than zero and up to about 5%, by weight, up to about 5%, by weight, of manganese oxide, up to about 0.2%, by weight, of an alkali metal carbonate and up to about 0.2%, by weight, of molybdenite. The inorganic binder is capable of a strong bridging action between zinc ferrite particles during induration and the organic binder is capable of burning away during induration to form a porous structure, pelletizing the resulting mixture with water, drying the resulting pellets and indurating the dried pellets and a temperature of about 1600/sup 0/F to about 2000/sup 0/F to form strong, porous sorbent pellets having a crush strength of about 5 to about 20 lbs. Dead Weight Load.

  4. Pellet injector development at ORNL (Oak Ridge National Laboratory)

    SciTech Connect

    Gouge, M.J.; Argo, B.E.; Baylor, L.R.; Combs, S.K.; Fehling, D.T.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Milora, S.L.; Qualls, A.L.; Schechter, D.E.; Simmons, D.W.; Sparks, D.O.; Tsai, C.C.

    1990-01-01

    Advanced plasma fueling systems for magnetic confinement experiments are under development at Oak Ridge National Laboratory (ORNL). The general approach is that of producing and accelerating frozen hydrogenic pellets to speeds in the kilometer-per-second range by either pneumatic (light-gas gun) or mechanical (centrifugal force) techniques. ORNL has recently provided a centrifugal pellet injector for the Tore Supra tokamak and a new, simplified, eight-shot pneumatic injector for the Advanced Toroidal Facility stellarator at ORNL. Hundreds of tritium and DT pellets were accelerated at the Tritium Systems Test Assembly facility at Los Alamos in 1988--89. These experiments, done in a single-shot pipe-gun system, demonstrated the feasibility of forming and accelerating tritium pellets at low {sup 3}He levels. A new, tritium-compatible extruder mechanism is being designed for longer-pulse DT applications. Two-stage light-gas guns and electron beam rocket accelerators for speeds of the order of 2--10 km/s are also under development. Recently, a repeating, two-stage light-gas gun accelerated 10 surrogate pellets at a 1-Hz repetition rate to speeds in the range of 2--3 km/s; and the electron beam rocket accelerator completed initial feasibility and scaling experiments. ORNL has also developed conceptual designs of advanced plasma fueling systems for the Compact Ignition Tokamak and the International Thermonuclear Experimental Reactor.

  5. Massive Pellet and Rupture Disk Testing for Disruption Mitigation Applications

    SciTech Connect

    Combs, Stephen Kirk; Meitner, Steven J; Baylor, Larry R; Caughman, John B; Commaux, Nicolas JC; Fehling, Dan T; Foust, Charles R; Jernigan, Thomas C; McGill, James M; Parks, P. B.; Rasmussen, David A

    2009-01-01

    Injection of massive quantities of noble gases or D2 has proven to be effective at mitigating some of the deleterious effects of disruptions in tokamaks. Two alternative methods that might offer some advantages over the present technique for massive gas injection are shattering massive pellets and employing close-coupled rupture disks. Laboratory testing has been carried out to evaluate their feasibility. For the study of massive pellets, a pipe gun pellet injector cooled with a cryogenic refrigerator was fitted with a relatively large barrel (16.5 mm bore), and D2 and Ne pellets were made and were accelerated to speeds of ~600 and 300 m/s, respectively. Based on the successful proof-of-principle testing with the injector and a special double-impact target to shatter pellets, a similar system has been prepared and installed on DIII-D and should be ready for experiments later this year. To study the applicability of rupture disks for disruption mitigation, a simple test apparatus was assembled in the lab. Commercially available rupture disks of 1 in. nominal diameter were tested at conditions relevant for the application on tokamaks, including tests with Ar and He gases and rupture pressures of ~54 bar. Some technical and practical issues of implementing this technique on a tokamak are discussed.

  6. Progress with the High Speed Pellet Injector for Ignitor*

    NASA Astrophysics Data System (ADS)

    Frattolillo, A.; Migliori, S.; Podda, S.; Bombarda, F.; Baylor, L. R.; Combs, S. K.; Foust, C. R.; Meitner, S.; Fehling, D.; Coppi, B.; Roveta, G.

    2010-11-01

    The four barrel, two-stage Ignitor Pellet Injector (IPI) has been designed to reach speeds up to 4 km/s, for effective low field side injection into ignited plasmas (TeTi11 keV). The IPI has been developed in collaboration between ORNL and ENEA, who have built and tested two indipendent subsystems each. Previous experimental campaigns at ORNL verified that the equipments matched properly, while their respective control systems interfaced correctly. The injector performed outstandingly well, showing very good repeatability. However, the pellet diagnostics expressely developed for this device did not observe intact pellets over 2 km/s. Recently a new arrangement was successfully tested, accommodating both a two-stage gun and a standard propellant valve on each barrel, allowing seamless switching between standard and high speed operation on any or all gun barrels; the cryogenic system was also improved with supplemental cooling by liquid helium. Injection speeds up to 2.6 km/s were obtained, but pellets seldom remained intact above 2 km/s. Optimization of power levels of the upstream and downstream heaters, which up to date have been used sparingly, in the next campaign could help in attaining integral pellets at higher speeds. *Sponsored in part by ENEA and by the D.O.E.

  7. The New High Speed Pellet Injector for the Ignitor Experiment^*

    NASA Astrophysics Data System (ADS)

    Migliori, S.; Baylor, L. R.; Roveta, G.

    2005-10-01

    A four barrel, two-stage pellet injector for the Ignitor experiment is under construction in collaboration between the ENEA Laboratory at Frascati and Oak Ridge National Laboratory. The goal is to reach pellet velocities of about 4 km/s, capable of penetrating near the center of the plasma column when injected from the low field side, in order to control the density profile, especially during the crucial phase of the initial current ramp, and as a possible method to fuel the discharge or to provide fast burn control during the ignited phase. The innovative concepts at the basis of the injector design are the proper shaping of the propulsion gas pressure front and the use of fast valves to considerably reduce the requirements on the expansion volumes necessary to prevent the propulsion gas to reach the plasma chamber. The complete propelling and gas removal systems have been built and tested at CRIOTEC. ORNL is responsible for the design, construction, and testing of the pellet injector vacuum chamber, the cryogenic systems, the gun barrels, and pellet diagnostics. Integrated testing at high pellet speeds with a wide range of operating parameters explored is also going to be carried out at ORNL.

  8. 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.

  9. 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.

  10. 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.

  11. Plant Growth Promotion Activity of Keratinolytic Fungi Growing on a Recalcitrant Waste Known as “Hair Waste”

    PubMed Central

    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. PMID:26697226

  12. Attachment Capability of Antagonistic Yeast Rhodotorula glutinis to Botrytis cinerea Contributes to Biocontrol Efficacy

    PubMed Central

    Li, Boqiang; Peng, Huaimin; Tian, Shiping

    2016-01-01

    Rhodotorula glutinis as an antagonism show good biocontrol performance against various post-harvest diseases in fruits. In the present study, strong attachment capability of R. glutinis to spores and hyphae of Botrytis cinerea was observed. Further analysis showed that certain protein components on the yeast cell surface played critical role during the interaction between R. glutinis and B. cinerea. The components mainly distributed at the poles of yeast cells and might contain glycosylation modification, as tunicamycin treated yeast cells lost attachment capability to B. cinerea. To investigate contributions of attachment capability of R. glutinis to its biocontrol efficacy, yeast cells were mutagenized with 3% methane-sulfonic acid ethyl ester (EMS), and a mutant CE4 with stable non-attaching phenotype was obtained. No significant difference was found on colony, cell morphology, reproductive ability, and capsule formation between the mutant and wild-type. However, there was a distinct difference in India ink positive staining patterns between the two strains. Moreover, wild-type strain of R. glutinis showed better performance on inhibiting spore germination and mycelial growth of B. cinerea than CE4 strain when yeast cells and B. cinerea were co-cultured in vitro. In biocontrol assay, both wild-type and CE4 strains showed significant biocontrol efficacy against gray mold caused by B. cinerea in apple fruit, whereas, control effect of CE4 strain was lower than that of wild-type. Our findings provided new evidences that attachment capability of R. glutinis to B. cinerea contributed to its biocontrol efficacy. PMID:27199931

  13. Attachment Capability of Antagonistic Yeast Rhodotorula glutinis to Botrytis cinerea Contributes to Biocontrol Efficacy.

    PubMed

    Li, Boqiang; Peng, Huaimin; Tian, Shiping

    2016-01-01

    Rhodotorula glutinis as an antagonism show good biocontrol performance against various post-harvest diseases in fruits. In the present study, strong attachment capability of R. glutinis to spores and hyphae of Botrytis cinerea was observed. Further analysis showed that certain protein components on the yeast cell surface played critical role during the interaction between R. glutinis and B. cinerea. The components mainly distributed at the poles of yeast cells and might contain glycosylation modification, as tunicamycin treated yeast cells lost attachment capability to B. cinerea. To investigate contributions of attachment capability of R. glutinis to its biocontrol efficacy, yeast cells were mutagenized with 3% methane-sulfonic acid ethyl ester (EMS), and a mutant CE4 with stable non-attaching phenotype was obtained. No significant difference was found on colony, cell morphology, reproductive ability, and capsule formation between the mutant and wild-type. However, there was a distinct difference in India ink positive staining patterns between the two strains. Moreover, wild-type strain of R. glutinis showed better performance on inhibiting spore germination and mycelial growth of B. cinerea than CE4 strain when yeast cells and B. cinerea were co-cultured in vitro. In biocontrol assay, both wild-type and CE4 strains showed significant biocontrol efficacy against gray mold caused by B. cinerea in apple fruit, whereas, control effect of CE4 strain was lower than that of wild-type. Our findings provided new evidences that attachment capability of R. glutinis to B. cinerea contributed to its biocontrol efficacy. PMID:27199931

  14. Biocontrol potential of Trichoderma harzianum isolate T-aloe against Sclerotinia sclerotiorum in soybean.

    PubMed

    Zhang, Fuli; Ge, Honglian; Zhang, Fan; Guo, Ning; Wang, Yucheng; Chen, Long; Ji, Xiue; Li, Chengwei

    2016-03-01

    Sclerotinia stem rot, caused by Sclerotinia sclerotiorum (Lib.) de Bary is a major disease of soybean (Glycine max (L.) Merr.). At present, we revealed the three-way interaction between Trichoderma harzianum T-aloe, pathogen S. sclerotiorum and soybean plants in order to demonstrate biocontrol mechanism and evaluate biocontrol potential of T-aloe against S. sclerotiorum in soybean. In our experiments, T-aloe inhibited the growth of S. sclerotiorum with an efficiency of 56.3% in dual culture tests. T-aloe hyphae grew in parallel or intertwined with S. sclerotiorum hyphae and produced hooked contact branches, indicating mycoparasitism. Plate tests showed that T-aloe culture filtrate inhibited S. sclerotiorum growth with an inhibition efficiency of 51.2% and sclerotia production. T-aloe pretreatment showed growth-promoting effect on soybean plants. The activities of peroxidase, superoxide dismutase, and catalase increased, and the hydrogen peroxide (H2O2) as well as the superoxide radical (O2(-)) content in soybean leaves decreased after T-aloe pretreatment in response to S. sclerotiorum pathogen challenge. T-aloe treatment diminished damage caused by pathogen stress on soybean leaf cell membrane, and increased chlorophyll as well as total phenol contents. The defense-related genes PR1, PR2, and PR3 were expressed in the leaves of T-aloe-treated plants. In summary, T-aloe displayed biocontrol potential against S. sclerotiorum. This is the first report of unraveling biocontrol potential of Trichoderma Spp. to soybean sclerotinia stem rot from the three-way interaction between the biocontrol agent, pathogen S. sclerotiorum and soybean plants. PMID:26774866

  15. Analysis of Canadian and Irish forage, oats and commercially available equine concentrate feed for pathogenic fungi and mycotoxins

    PubMed Central

    2007-01-01

    Respiratory infections, recurrent airway obstruction (RAO) and exercise induced pulmonary haemorrhage (EIPH) are major causes of poor performance in horses. Fungi and mycotoxins are now recognised as a major cause of these conditions. The most notable fungi are Aspergillus and Fusarium. Fungal spores can originate from forage, bedding and feed and, in turn, these fungal spores can produce a series of mycotoxins as secondary metabolites. This study set out to ascertain the degree of fungal and mycotoxin contamination in feed and fodder used in Irish racing yards over a one-year period. Weather conditions in forage producing areas were sampled by Met Eireann and the Canadian Meteorological Service. Fifty per cent of Irish hay, 37% of haylage and 13% of Canadian hay contained pathogenic fungi. Of the mycotoxins, T2 and zearalenone were most prominent. Twenty-one per cent of Irish hay and 16% of pelleted feed contained zearalenone. Forty per cent of oats and 54% of pelleted feed contained T2 toxins. PMID:21851693

  16. Some coprophilous fungi from Kenya.

    PubMed

    Caretta, G; Piontelli, E; Savino, E; Bulgheroni, A

    1998-01-01

    The occurrence of coprophilous fungi on samples of antelope, buffalo, zebra and hippopotamus dung collected from the Marula Estates in Kenya was recorded. A hundred and seventy three fungal isolates representative of 40 genera and 59 species were identified. Among these species, 23 were Ascomycetes (39%), 30 Deuteromycetes (50.8%), 5 Zygomycetes (8.5%) and 1 Basidiomycete (1.7%). Ascobolus immersus, Coprotus niveus, Iodophanus carneus, Lasiobolus lasioboloides, Podospora anserina, P. australis and Sporormiella minima were the dominant species occurring in the dung of these animals. Notes on infrequent or interesting Ascomycetes include Kernia nitida, Saccobolus versicolor, Sordaria fimicola and others. The interdependence of the vegetation of this area with the fungi occurring on the dung of these animals is discussed. PMID:16284849

  17. Proteomics of Plant Pathogenic Fungi

    PubMed Central

    González-Fernández, Raquel; Prats, Elena; Jorrín-Novo, Jesús V.

    2010-01-01

    Plant pathogenic fungi cause important yield losses in crops. In order to develop efficient and environmental friendly crop protection strategies, molecular studies of the fungal biological cycle, virulence factors, and interaction with its host are necessary. For that reason, several approaches have been performed using both classical genetic, cell biology, and biochemistry and the modern, holistic, and high-throughput, omic techniques. This work briefly overviews the tools available for studying Plant Pathogenic Fungi and is amply focused on MS-based Proteomics analysis, based on original papers published up to December 2009. At a methodological level, different steps in a proteomic workflow experiment are discussed. Separate sections are devoted to fungal descriptive (intracellular, subcellular, extracellular) and differential expression proteomics and interactomics. From the work published we can conclude that Proteomics, in combination with other techniques, constitutes a powerful tool for providing important information about pathogenicity and virulence factors, thus opening up new possibilities for crop disease diagnosis and crop protection. PMID:20589070

  18. Ambrosia fungi in the insect-fungi symbiosis in relation to cork oak decline.

    PubMed

    Henriques, Joana; Inácio, Maria Lurdes; Sousa, Edmundo

    2006-09-01

    Ambrosia fungi live associated with beetles (Scolytidae and Platypodidae) in host trees and act as a food source for the insects. The symbiotic relation is important to the colonizing strategies of host trees by beetles. Ambrosia fungi are dimorphic: they grow as ambrosial form and as mycelium. The fungi are highly specialized, adapted to a specific beetle and to the biotope where they both live. In addition other fungi have been found such as tree pathogenic fungi that may play a role in insects host colonization success. Saprophytic fungi are also present in insects galleries. These may decompose cellulose and/or be antagonistic to other less beneficial fungi. This paper summarizes the importance of ambrosia fungi and the interaction with insects and hosts. The possibility of the transport of pathogenic fungi by Platypus cylindrus to cork oak thus contributing for its decline is discussed.

  19. 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.

  20. 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.

  1. Electromagnetic launch of mm-size pellets to great velocities

    SciTech Connect

    Drobyshevski, E.M.; Zhukov, B.G.; Kurakin, R.O.; Sakharov, V.A.; Studenkov, A.M.

    1994-11-01

    Small body launching that uses gas or plasma faces the fundamental problem caused by excess energy loss that is due to the great wall surface/volume ratio of the barrel. For example, the efficiency of the plasma armature (PA) rail-gun acceleration is maximum for 8-10 mm-size bodies and drops as their size decreases. That is why in the case of nuclear fusion applications, where 1-2 mm-size pellets at 5-10 km/s velocity are desirable, electromagnetic launchers have not yet demonstrated an advantage over light-gas guns and one is now forced to search for a compromise between the pellet size (increasing it up to 3-4 mm) and its velocity (decreasing it down to {approx}3 km/s). As a whole, the probability of attaining 5-10 km/s velocity for 1-2 mm pellets seems to be rather remote at the present.

  2. Vesicular transport systems in fungi

    PubMed Central

    Rodrigues, Marcio L; Nosanchuk, Joshua D; Schrank, Augusto; Vainstein, Marilene H; Casadevall, Arturo; Nimrichter, Leonardo

    2014-01-01

    Canonical and unconventional mechanisms of secretion in many eukaryotic cells are relatively well known. In contrast to the situation in animal cells, mechanisms of secretion in fungi must include the capacity for trans-cell wall passage of macromolecules to the extracellular space. Although these mechanisms remain somewhat elusive, several studies in recent years have suggested that vesicular transport is required for trans-cell wall secretion of large molecules. Several fungal molecules, including proteins, lipids, polysaccharides and pigments, are released to the extracellular space in vesicles. In pathogenic fungi, a number of these vesicular components are associated with fungal virulence. Indeed, extracellular vesicles produced by fungi can interfere with the immunomodulatory activity of host cells. Fungal vesicles share many functional aspects with mammalian exosomes and extracellular vesicles produced by bacteria, plants and protozoa, but their cellular origin remains unknown. Here, we discuss the involvement of vesicular transport systems in fungal physiology and pathogenesis, making parallels with the mammalian, bacterial, protozoan and plant cell literature. PMID:22082294

  3. Effector proteins of rust fungi.

    PubMed

    Petre, Benjamin; Joly, David L; Duplessis, Sébastien

    2014-01-01

    Rust fungi include many species that are devastating crop pathogens. To develop resistant plants, a better understanding of rust virulence factors, or effector proteins, is needed. Thus far, only six rust effector proteins have been described: AvrP123, AvrP4, AvrL567, AvrM, RTP1, and PGTAUSPE-10-1. Although some are well established model proteins used to investigate mechanisms of immune receptor activation (avirulence activities) or entry into plant cells, how they work inside host tissues to promote fungal growth remains unknown. The genome sequences of four rust fungi (two Melampsoraceae and two Pucciniaceae) have been analyzed so far. Genome-wide analyses of these species, as well as transcriptomics performed on a broader range of rust fungi, revealed hundreds of small secreted proteins considered as rust candidate secreted effector proteins (CSEPs). The rust community now needs high-throughput approaches (effectoromics) to accelerate effector discovery/characterization and to better understand how they function in planta. However, this task is challenging due to the non-amenability of rust pathosystems (obligate biotrophs infecting crop plants) to traditional molecular genetic approaches mainly due to difficulties in culturing these species in vitro. The use of heterologous approaches should be promoted in the future.

  4. Natural plasmids of filamentous fungi.

    PubMed Central

    Griffiths, A J

    1995-01-01

    Among eukaryotes, plasmids have been found in fungi and plants but not in animals. Most plasmids are mitochondrial. In filamentous fungi, plasmids are commonly encountered in isolates from natural populations. Individual populations may show a predominance of one type, but some plasmids have a global distribution, often crossing species boundaries. Surveys have shown that strains can contain more than one type of plasmid and that different types appear to be distributed independently. In crosses, plasmids are generally inherited maternally. Horizontal transmission is by cell contact. Circular plasmids are common only in Neurospora spp., but linear plasmids have been found in many fungi. Circular plasmids have one open reading frame (ORF) coding for a DNA polymerase or a reverse transcriptase. Linear plasmids generally have two ORFs, coding for presumptive DNA and RNA polymerases with amino acid motifs showing homology to viral polymerases. Plasmids often attain a high copy number, in excess of that of mitochondrial DNA. Linear plasmids have a protein attached to their 5' end, and this is presumed to act as a replication primer. Most plasmids are neutral passengers, but several linear plasmids integrate into mitochondrial DNA, causing death of the host culture. Inferred amino acid sequences of linear plasmid ORFs have been used to plot phylogenetic trees, which show a fair concordance with conventional trees. The circular Neurospora plasmids have replication systems that seem to be evolutionary intermediates between the RNA and the DNA worlds. PMID:8531891

  5. Transport Systems in Halophilic Fungi.

    PubMed

    Plemenitaš, Ana; Konte, Tilen; Gostinčar, Cene; Cimerman, Nina Gunde

    2016-01-01

    Fungi that tolerate very high environmental NaCl concentrations are good model systems to study mechanisms that enable them to endure osmotic and salinity stress. The whole genome sequences of six such fungal species have been analysed: Hortaea werneckii, Wallemia ichthyophaga and four Aureobasidium spp.: A. pullulans, A. subglaciale, A. melanogenum and A. namibiae. These fungi show different levels of halotolerance, with the presence of numerous membrane transport systems uncovered here that are believed to maintain physiological intracellular concentrations of alkali metal cations. Despite some differences, the intracellular cation contents of H. werneckii, A. pullulans and W. ichthyophaga remain low even under extreme extracellular salinities, which suggests that these species have efficient cation transport systems. We speculate that cation transporters prevent intracellular accumulation of Na(+), and thus avoid the toxic effects that such Na(+) accumulation would have, while also maintaining the high K(+)/Na(+) ratio that is required for the full functioning of the cell - another crucial task in high-Na(+) environments. This chapter primarily summarises the cation transport systems of these selected fungi, and it also describes other membrane transporters that might be involved in their mechanisms of halotolerance.

  6. Dye removal by immobilised fungi.

    PubMed

    Rodríguez Couto, Susana

    2009-01-01

    Dyes are widely used within the food, pharmaceutical, cosmetic, printing, textile and leather industries. This has resulted in the discharge of highly coloured effluents that affect water transparency and gas solubility in water bodies. Furthermore, they pose a problem because of their carcinogenicity and toxicity. Therefore, removal of such dyes before discharging them into natural water streams is essential. For this, appropriate treatment technologies are required. The treatment of recalcitrant and toxic dyes with traditional technologies is not always effective or may not be environmentally friendly. This has impelled the search for alternative technologies such as biodegradation with fungi. In particular, ligninolytic fungi and their non-specific oxidative enzymes have been reported to be responsible for the decolouration of different synthetic dyes. Thus, the use of such fungi is becoming a promising alternative to replace or complement the current technologies for dye removal. Processes using immobilised growing cells seem to be more promising than those with free cells, since the immobilisation allows using the microbial cells repeatedly and continuously. This paper reviews the application of fungal immobilisation to dye removal. PMID:19211032

  7. 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.

  8. 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.

  9. Role of Antagonistic Microorganisms and Organic Amendment in Stimulating the Defense System of Okra Against Root Rotting Fungi.

    PubMed

    Shafique, Hafiza Asma; Sultana, Viqar; Ara, Jehan; Ehteshamul-Haque, Syed; Athar, Mohammad

    2015-01-01

    Without application of chemical pesticides control of soilborne diseases is a great challenge. Stimulation of natural plant's defense is considered as one of the most promising alternative strategy for crop protection. Organic amendment of soil besides direct suppressing the pathogen, has been reported to have an influence on phytochemicals in plants. In the present study, Pseudomonas aeruginosa, a plant growth promoting rhizobacterium and Paecilomyces lilacinus, an egg parasite of root knot and cysts nematodes were examined individually and in combination in soil amended with cotton cake for suppressing the root rotting fungi and stimulating the synthesis of polyphenols and improving the antioxidant status in okra. Application of P. aeruginosa and P. lilacinus in soil amended with cotton cake significantly (P < 0.05) suppressed Macrophomina phaseolina, Fusarium oxysporum, and Fusarium solani with complete reduction of Rhizoctonia solani. Combine use of biocontrol agents in cotton cake amended soil showed maximum positive impact on plant growth, polyphenol concentration and antioxidant activity in okra.

  10. Role of Antagonistic Microorganisms and Organic Amendment in Stimulating the Defense System of Okra Against Root Rotting Fungi.

    PubMed

    Shafique, Hafiza Asma; Sultana, Viqar; Ara, Jehan; Ehteshamul-Haque, Syed; Athar, Mohammad

    2015-01-01

    Without application of chemical pesticides control of soilborne diseases is a great challenge. Stimulation of natural plant's defense is considered as one of the most promising alternative strategy for crop protection. Organic amendment of soil besides direct suppressing the pathogen, has been reported to have an influence on phytochemicals in plants. In the present study, Pseudomonas aeruginosa, a plant growth promoting rhizobacterium and Paecilomyces lilacinus, an egg parasite of root knot and cysts nematodes were examined individually and in combination in soil amended with cotton cake for suppressing the root rotting fungi and stimulating the synthesis of polyphenols and improving the antioxidant status in okra. Application of P. aeruginosa and P. lilacinus in soil amended with cotton cake significantly (P < 0.05) suppressed Macrophomina phaseolina, Fusarium oxysporum, and Fusarium solani with complete reduction of Rhizoctonia solani. Combine use of biocontrol agents in cotton cake amended soil showed maximum positive impact on plant growth, polyphenol concentration and antioxidant activity in okra. PMID:26373176

  11. Suppression of the biocontrol agent trichoderma harzianum by mycelium of the arbuscular mycorrhizal fungus glomus intraradices in root-free soil

    PubMed

    Green; Larsen; Olsson; Jensen; Jakobsen

    1999-04-01

    Trichoderma harzianum is an effective biocontrol agent against several fungal soilborne plant pathogens. However, possible adverse effects of this fungus on arbuscular mycorrhizal fungi might be a drawback in its use in plant protection. The objective of the present work was to examine the interaction between Glomus intraradices and T. harzianum in soil. The use of a compartmented growth system with root-free soil compartments enabled us to study fungal interactions without the interfering effects of roots. Growth of the fungi was monitored by measuring hyphal length and population densities, while specific fatty acid signatures were used as indicators of living fungal biomass. Hyphal 33P transport and beta-glucuronidase (GUS) activity were used to monitor activity of G. intraradices and a GUS-transformed strain of T. harzianum, respectively. As growth and metabolism of T. harzianum are requirements for antagonism, the impact of wheat bran, added as an organic nutrient source for T. harzianum, was investigated. The presence of T. harzianum in root-free soil reduced root colonization by G. intraradices. The external hyphal length density of G. intraradices was reduced by the presence of T. harzianum in combination with wheat bran, but the living hyphal biomass, measured as the content of a membrane fatty acid, was not reduced. Hyphal 33P transport by G. intraradices also was not affected by T. harzianum. This suggests that T. harzianum exploited the dead mycelium but not the living biomass of G. intraradices. The presence of external mycelium of G. intraradices suppressed T. harzianum population development and GUS activity. Stimulation of the hyphal biomass of G. intraradices by organic amendment suggests that nutrient competition is a likely means of interaction. In conclusion, it seemed that growth of and phosphorus uptake by the external mycelium of G. intraradices were not affected by the antagonistic fungus T. harzianum; in contrast, T. harzianum was adversely

  12. Response to Delibes-Mateos et al. : Pellet size matters

    NASA Astrophysics Data System (ADS)

    Rueda, Marta; Rebollo, Salvador; Gálvez-Bravo, Lucía

    2009-05-01

    In Rueda et al. [Rueda, M., Rebollo, S., Gálvez-Bravo, L., 2008. Age and season determine European rabbit habitat use in Mediterranean ecosystems. Acta Oecol. 34, 266-273] we used a threshold of 6 mm faecal pellet diameter to differentiate between adult and juvenile European rabbit ( Oryctolagus cuniculus) habitat use. Delibes-Mateos et al. designed a housing experiment with 12 adult rabbits and criticised the choice of 6 mm as a threshold to separate adult and juvenile rabbit pellets, claiming that adults can produce pellets both larger and smaller than 6 mm in similar proportions. In response to their criticism we argue the following. The selection of a 6 mm threshold has a bibliographic basis, it is not a new method developed by Rueda et al. and produces consistent results when applied in the field. Assuming that Delibes-Mateos et al. results are accurate, we should have found a greater number of <6 mm pellets than >6 mm, overall and seasonally, which is not the case. We believe that the use of commercial pelleted food, keeping animals isolated in small cages for over a year, and the use of adult rabbits only, makes the experimental design used by these authors not suitable to refute the usefulness of separating rabbit pellets smaller and larger than 6 mm diameter as indicators of changes in the relative abundance of juvenile and adult rabbits in the field. Finally, we agree with the authors that the use of indirect methods of animal aging would require case-specific validation studies; however, we believe these studies should be correctly designed.

  13. Formulation and evaluation of olanzapine matrix pellets for controlled release

    PubMed Central

    Vishal Gupta, N.; Balamuralidhara, V.; Mohammed Khan, S.

    2011-01-01

    Background and the purpose of the study Olanzapine is an antipsychotic used in treatment of schizophrenia. This research was carried out to design oral controlled release matrix pellets of water insoluble drug Olanzapine (OZ), using blend of Sodium Alginate (SA) and Glyceryl Palmito-Stearate (GPS) as matrix polymers, micro crystalline cellulose (MCC) as spheronizer enhancer and Sodium Lauryl Sulphate (SLS) as pore forming agent. Methods OZ formulations were developed by the pelletization technique by drug loaded pellets and characterized with regard to the drug content, size distribution, Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction study (XRD). Stability studies were carried out on the optimized formulation for a period of 90 days at 40±2 °C and 75±5% relative humidity. Results and major conclusion The drug content was in the range of 93.34–98.12%. The mean particle size of the drug loaded pellets was in the range 1024 to 1087µm. SEM photographs and calculated sphericity factor confirmed that the prepared formulations were spherical in nature. The compatibility between drug and polymers in the drug loaded pellets was confirmed by DSC and FTIR studies. Stability studies indicated that pellets are stable. XRD patterns revealed the crystalline nature of the pure OZ. Loose surface crystal study indicated that crystalline OZ is present in all formulations and more clear in formulation F5. Drug release was controlled for more than 24 hrs and mechanism of the drug release followed by Fickian diffusion. It may be concluded that F5 is an ideal formulation for once a day administration. PMID:22615665

  14. Hydro-mechanical behaviour of bentonite pellet mixtures

    NASA Astrophysics Data System (ADS)

    Hoffmann, C.; Alonso, E. E.; Romero, E.

    Granular mixtures made of high-density pellets of bentonite are being evaluated as an alternative buffer material for waste isolation. Ease of handling is an often-mentioned advantage. The paper described the experimental program performed to characterize the hydro-mechanical behaviour of compacted pellet’s mixtures used in the engineered barrier (EB) experiment. The material tested in the laboratory was based in the pellet’s mixtures actually used for the emplacement of the EB in situ experiment. Grain size distribution was adjusted to a maximum pellet size compatible with the specimen’s dimensions. Dry densities of statically compacted specimens varied in most of the cases in the range: 1.3-1.5 Mg/m 3. Pellets had a very high dry density, close to 2 Mg/m 3. The outstanding characteristic of these mixtures is its discontinuous porosity. Pore sizes of the compacted pellets vary around 10 nm. However the inter-pellet size of the pores is four to five orders of magnitude higher. This double porosity and the highly expansive nature of the pellets controlled all the hydraulic and mechanical properties of the mixture. Tests performed include infiltration tests using different water injection rates and mechanisms of water transfer (in liquid and vapour phases), suction controlled oedometer tests and swelling pressure tests. The interpretation of some of the tests performed required backanalysis procedures using a hydro-mechanical (HM) computer code. Material response was studied within the framework of the elastoplastic constitutive model proposed by Alonso et al. [Alonso, E.E., Gens, A., Josa, A., 1990. A constitutive model for partially saturated soils. Géotechnique 40 (3), 405-430] (Barcelona Basic Model, BBM). Parameters for the model were identified and also a set of hydraulic laws necessary to perform coupled HM analysis.

  15. Control System for the NSTX Lithium Pellet Injector

    SciTech Connect

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

    2003-10-27

    The Lithium Pellet Injector (LPI) is being developed for the National Spherical Torus Experiment (NSTX). The LPI will inject ''pellets'' of various composition into the plasma in order to study wall conditioning, edge impurity transport, liquid limiter simulations, and other areas of research. The control system for the NSTX LPI has incorporated widely used advanced technologies, such as LabVIEW and PCI bus I/O boards, to create a low-cost control system which is fully integrated into the NSTX computing environment. This paper will present the hardware and software design of the computer control system for the LPI.

  16. Shattered Pellet Disruption Mitigation Technology Development for ITER

    SciTech Connect

    Baylor, Larry R; Combs, Stephen Kirk; Jernigan, T. C.; Meitner, Steven J; Edgemon, Timothy D; Parks, P. B.; Commaux, Nicolas JC; Maruyama, S.; Caughman, John B; Rasmussen, David A

    2010-01-01

    The mitigation of first wall thermal and mechanical loads and damage from runaway electrons during disruptions are critical for successful long term operation of ITER. Disruption mitigation tools based on shattered pellet injection are being developed at Oak Ridge National Laboratory that can be employed on ITER to provide the necessary mitigation of thermal and mechanical loads from disruptions as well as provide collisional damping to inhibit the formation of runaway electrons . Here we present progress on the development of the technology to provide reliable disruption mitigation with large shattered cryogenic pellets. An example of how this concept can be employed on ITER is discussed.

  17. Tracer-encapsulated pellet injector for plasma diagnostics

    NASA Astrophysics Data System (ADS)

    Sudo, S.; Viniar, I.; Lukin, A.; Reznichenko, P.; Umov, A.

    2005-05-01

    An injector for making solid hydrogen pellets around impurity cores has been developed for plasma transport study in large helical device. A technique has been employed for automatic loading carbon or polystyrene cores of 0.2 mm diameter from a gun magazine to a light-gas gun barrel. The injector is equipped with a cryocooler and is able to form a 3.2 mm long and 3 mm diameter cylindrical solid hydrogen pellet at 7-8 K with an impurity core in its center within 6 min and to inject it in the light-gas gun up to 1 km/s.

  18. Hydrogen-encapsulated impurity pellet injector for plasma diagnostics

    NASA Astrophysics Data System (ADS)

    Viniar, I.; Reznichenko, P.; Lukin, A.; Umov, A.; Sudo, S.

    2001-06-01

    A novel technology is suggested for making solid hydrogen shells around impurity pellets to be injected into plasmas of fusion devices with a view to looking into its transport properties. In proof-of-principle tests, a 3 mm long and 3 mm diameter cylindrical solid hydrogen shell was formed around a 0.2 mm diameter globular pellet at a temperature of 8-11 K within 5 min and accelerated in a pipe-gun barrel up to 1 km/s.

  19. Role of the methylcitrate cycle in growth, antagonism and induction of systemic defence responses in the fungal biocontrol agent Trichoderma atroviride.

    PubMed

    Dubey, Mukesh K; Broberg, Anders; Jensen, Dan Funck; Karlsson, Magnus

    2013-12-01

    Methylisocitrate lyase (MCL), a signature enzyme of the methylcitrate cycle, which cleaves methylisocitrate to pyruvate and succinate, is required for propionate metabolism, for secondary metabolite production and for virulence in bacteria and fungi. Here we investigate the role of the methylcitrate cycle by generating an mcl deletion mutant in the fungal biocontrol agent Trichoderma atroviride. Gene expression analysis shows that a basal expression of mcl is observed in all growth conditions tested. Phenotypic analysis of an mcl deletion mutant suggests the requirement of MCL in propionate resistance, growth, conidial pigmentation and germination, and abiotic stress tolerance. A plate confrontation assay did not show a difference between the WT and the Δmcl strain in antagonism towards Botrytis cinerea. However, the Δmcl strain displays reduced antagonism towards B. cinerea based on a secretion assay. Furthermore, an in vitro root colonization assay shows that the Δmcl strain had reduced ability to colonize Arabidopsis thaliana roots, which results in reduced induction of systemic resistance towards B. cinerea. These data show that MCL is important not only for growth and development in T. atroviride but also in antagonism, root colonization and induction of defence responses in plants.

  20. Partial purification, characterization, and kinetic studies of a low-molecular-weight, alkali-tolerant chitinase enzyme from Bacillus subtilis JN032305, A potential biocontrol strain.

    PubMed

    Shivakumar, Srividya; Karmali, Anika Nayak; Ruhimbana, Charles

    2014-01-01

    A new alkalophilic low-molecular-mass chitinase of 14 kD from the potent biocontrol agent Bacillus subtilis JN032305 was partially purified and enzymology of the chitinase was studied. The enzyme showed optimal pH of 9.0 and temperature of 50°C. The enzyme was found stable during the 60-min incubation at 50 °C. The chitinase was inhibited by group specific agents like IAA, DAN, TLCK, and SDS and metal ions Mg(2+), Ca(2+), Fe(2+), Mn(2+), Ba(2+), and Hg(2+), whereas Zn(2+) did not show significant inhibitory effect against the chitinase. PMSF partially inhibited the enzyme. Substrates specificity tests indicated that the enzyme showed 75% of relative activity on glycol chitin, 58% on carboxymethylcellulose (CMC), 33% on chitin flakes, and 166% laminarin compared to that on colloidal chitin. The enzyme also hydrolyzed 4-methylumbelliferyl-N-acetyl-D-glucosaminide, indicating its chitobiase activity. The chitinase of this study has broad specificity, which could hydrolyze not only the glycosidic bond in GlcNAc-GlcNAc but also that of related carbohydrates with glycosidic linkages. The partially purified chitinase not only showed antifungal activity against Rhizoctonia solani and Colletotrichum gloeosporioides, two potent phytopathogens of chilli, but also increased the germination of chilli seeds when infected with the two potent phytopathogenic fungi. PMID:24499366

  1. Pichia angusta is an effective biocontrol yeast against postharvest decay of apple fruit caused by Botrytis cinerea and Monilia fructicola.

    PubMed

    Fiori, Stefano; Fadda, Angela; Giobbe, Sara; Berardi, Enrico; Migheli, Quirico

    2008-09-01

    The efficacy of eight isolates of Pichia angusta against three common postharvest pathogens of apple fruit was evaluated for the first time. All tested strains showed significant biocontrol activity against both Botrytis cinerea and Monilia fructicola, whereas efficacy against Penicillium expansum was poor. A leucine-auxotrophic mutant had no significant biocontrol activity against brown rot of apple, while the addition of 0.6-1.2 g L(-1) leucine in the fruit wound fully restored the biocontrol activity of this mutant against M. fructicola. Given the extremely well-developed classical and molecular genetics, the availability of genomic libraries, and its complete genomic sequence, this species can serve to elucidate the mechanisms related to biocontrol capacity.

  2. Evaluation of the sea anemone Anthothoe albocincta as an augmentative biocontrol agent for biofouling on artificial structures.

    PubMed

    Atalah, Javier; Bennett, Holly; Hopkins, Grant A; Forrest, Barrie M

    2013-01-01

    Augmentative biocontrol, defined as the use of indigenous natural enemies to control pest populations, has not been explored extensively in marine systems. This study tested the potential of the anemone Anthothoe albocincta as a biocontrol agent for biofouling on submerged artificial structures. Biofouling biomass was negatively related to anemone cover. Treatments with high anemone cover (>35%) led to significant changes in biofouling assemblages compared to controls. Taxa that contributed to these changes differed among sites, but included reductions in cover of problematic fouling organisms, such as solitary ascidians and bryozoans. In laboratory trials, A. albocincta substantially prevented the settlement of larvae of the bryozoan Bugula neritina when exposed to three levels of larval dose, suggesting predation as an important biocontrol mechanism, in addition to space pre-emption. This study demonstrated that augmentative biocontrol using anemones has the potential to reduce biofouling on marine artificial structures, although considerable further work is required to refine this tool before its application.

  3. Fuel pins with both target and fuel pellets in an isotope-production reactor

    DOEpatents

    Cawley, W.E.; Omberg, R.P.

    1982-08-19

    A method is described for producing tritium in a fast breeder reactor cooled with liquid metal. Lithium target pellets are placed in close contact with fissile fuel pellets in order to increase the tritium production rate.

  4. Study of Organic and Inorganic Binders on Strength of Iron Oxide Pellets

    NASA Astrophysics Data System (ADS)

    Srivastava, Urvashi; Kawatra, S. Komar; Eisele, Timothy C.

    2013-08-01

    Bentonite is a predominant binder used in iron ore pelletization. However, the presence of a high content of silica and alumina in bentonite is considered undesirable for ironmaking operations. The objective of this study was to identify the alternatives of bentonite for iron ore pelletization. To achieve this goal, different types of organic and inorganic binders were utilized to produce iron oxide pellets. The quality of these iron oxide pellets was compared with pellets made using bentonite. All pellets were tested for physical strength at different stages of pelletization to determine their ability to survive during shipping and handling. The results show that organic binders such as lactose monohydrate, hemicellulose, and sodium lignosulfonate can provide sufficient strength to indurated pellets.

  5. Techno-economic assessment of pellets produced from steam pretreated biomass feedstock

    DOE PAGESBeta

    Shahrukh, Hassan; Oyedun, Adetoyese Olajire; Kumar, Amit; Ghiasi, Bahman; Kumar, Linoj; Sokhansanj, Shahab

    2016-03-10

    Minimum production cost and optimum plant size are determined for pellet plants for three types of biomass feedstock e forest residue, agricultural residue, and energy crops. The life cycle cost from harvesting to the delivery of the pellets to the co-firing facility is evaluated. The cost varies from 95 to 105 t-1 for regular pellets and 146–156 t-1 for steam pretreated pellets. The difference in the cost of producing regular and steam pretreated pellets per unit energy is in the range of 2e3 GJ-1. The economic optimum plant size (i.e., the size at which pellet production cost is minimum) ismore » found to be 190 kt for regular pellet production and 250 kt for steam pretreated pellet. Furthermore, sensitivity and uncertainty analyses were carried out to identify sensitivity parameters and effects of model error.« less

  6. Durable regenerable sorbent pellets for removal of hydrogen sulfide from coal gas

    SciTech Connect

    Siriwardane, R.V.

    1995-12-31

    Pellets for removing hydrogen sulfide from a coal gasification stream at an elevated temperature are presented in durable form, usable over repeated cycles of absorption and regeneration. The pellets include a material reactive with hydrogen sulfide, in particular zinc oxide, a binder, and an inert material, in particular calcium sulfate (Drierite), having a particle size substantially larger than other components of the pellets. A second inert material and a promoter may also be included. Preparation of the pellets may be carried out by dry, solid-state mixing of components, moistening the mixture, and agglomerating it into pellets, followed by drying and calcining. Pellet size is selected, depending on the type of reaction bed for which the pellets are intended. The use of inert material with a large particle size provides a stable pellet structure with increased porosity, enabling effective gas contact and prolonged mechanical durability.

  7. Solubilization of insoluble phosphates by thermophilic fungi.

    PubMed

    Singh, C P; Mishra, M M; Yadav, K S

    1980-01-01

    The solubilization of tricalcium phosphate and rock phosphate and assimilation of solubilized P by thermophilic fungi isolated from compost were studied. The solubilization of tricalcium phosphate was greater than that of rock phosphate on inoculation with fungi in liquid medium, but growth of most of the fungi was greater in rock phosphate. Torula thermophila solubilized tricalcium phosphate maximally. There was solubilization of rock phosphate in semi-solid lignocellulose medium by Aspergillus fumigatus.

  8. LOW EMISSION AND HIGH EFFICIENCY RESIDENTIAL PELLET-FIRED HEATERS

    EPA Science Inventory

    The paper gives results of air emissions testing and efficiency testing on new commercially available under-feed and top-feed residential heaters burning hardwood- and softwood-based pellets. The results were compared with data from earlier models. Reductions in air emissions w...

  9. USE OF PELLETED LETTUCE SEEDS IN BIOABAILABILITY STUDIES

    EPA Science Inventory

    Lettuce (Latuca sativa L., cv. Buttercrunch) is one of the most common and sensitive test organisms, among plants, used in toxicology and bioavailability studies. Much of the available lettuce seeds in commercial channels are pelleted to allow for precision machine planting. Th...

  10. USE OF PELLETED LETTUCE SEEDS IN BIOAVAILABILITY STUDIES

    EPA Science Inventory

    Lettuce (Latuca sativa L., cv. Buttercrunch) is one of the most common and sensitive test organisms, among plants, used in toxicology and bioavailability studies. Much of the available lettuce seeds in commercial channels are pelleted to allow for precision machine planting. Th...

  11. Assessment of Biomass Pelletization Options for Greensburg, Kansas

    SciTech Connect

    Haase, S.

    2010-05-01

    This report provides an overview of a technical report on an assessment NREL conducted in Greensburg, Kansas, to identify potential opportunities to develop a biomass pelletization or briquetting plant in the region. See NREL/TP-7A2-45843 for the Executive Summary of this report.

  12. Method for producing pellets for use in a cryoblasting process

    DOEpatents

    Foster, Christopher A.; Fisher, Paul W.

    1997-01-01

    A cryoblasting process having a centrifugal accelerator for accelerating frozen pellets of argon or carbon dioxide toward a target area utilizes an accelerator throw wheel designed to induce, during operation, the creation of a low-friction gas bearing within internal passages of the wheel which would otherwise retard acceleration of the pellets as they move through the passages. An associated system and method for removing paint from a surface with cryoblasting techniques involves the treating, such as a preheating, of the painted surface to soften the paint prior to the impacting of frozen pellets thereagainst to increase the rate of paint removal. A system and method for producing large quantities of frozen pellets from a liquid material, such as liquid argon or carbon dioxide, for use in a cryoblasting process utilizes a chamber into which the liquid material is introduced in the form of a jet which disintegrates into droplets. A non-condensible gas, such as inert helium or air, is injected into the chamber at a controlled rate so that the droplets freeze into bodies of relatively high density.

  13. XPS analysis of nikki N111 catalyst pellets

    SciTech Connect

    Kelly, Dan

    2007-03-26

    X-ray photoelectron spectroscopy (XPS) was performed on several pellets of Nikki N111 catalyst to determine elemental composition. Of specific interest, the Nikki MSDS for this material cites a 20 wt. % contribution from the species "Others". XPS was employed to determine more precisely the chemical composition of the pellets and search for potential catalytic metal species not identified on the MSDS. Results are tabulated in Table 1 below. XPS analysis of the chemical composition of the catalyst pellets compares favorably to the N ikki MSDS, if the assumption is made that the nickel in the catalyst is oxidized to Ni2O3. Specifically, using a 100 g sample basis, the 49 grams of nickel metal specified in the MSDS would carry 20 grams of oxygen if it were oxidized to Ni2O3, potentially accounting for the 20 wt. %"Others". XPS was able to confirm the presence of copper and chromium in the pellets, each expected at less than 1 atomic percent and quantified at 1-3 atomic percent concentrations, but no metal species not identified by the MSDS were detected.

  14. Connect Them Bones! An Interdisciplinary Study of Owl Pellets.

    ERIC Educational Resources Information Center

    Zipko, Stephen J.

    1983-01-01

    Discusses a field/laboratory study of the barn owl in which students collect and dissect owl pellets. Interdisciplinary lessons focus on eco-politics, reconstruction of owl prey skeletons, studies of predator-prey relationships, and construction/installation of nest boxes for owls and other birds. The unit begins and ends with an attitude…

  15. Imprint Desorption Electrospray Ionization Mass Spectrometry Imaging for Monitoring Secondary Metabolites Production during Antagonistic Interaction of Fungi.

    PubMed

    Tata, Alessandra; Perez, Consuelo; Campos, Michel L; Bayfield, Mark A; Eberlin, Marcos N; Ifa, Demian R

    2015-12-15

    Direct analysis of microbial cocultures grown on agar media by desorption electrospray ionization mass spectrometry (DESI-MS) is quite challenging. Due to the high gas pressure upon impact with the surface, the desorption mechanism does not allow direct imaging of soft or irregular surfaces. The divots in the agar, created by the high-pressure gas and spray, dramatically change the geometry of the system decreasing the intensity of the signal. In order to overcome this limitation, an imprinting step, in which the chemicals are initially transferred to flat hard surfaces, was coupled to DESI-MS and applied for the first time to fungal cocultures. Note that fungal cocultures are often disadvantageous in direct imaging mass spectrometry. Agar plates of fungi present a complex topography due to the simultaneous presence of dynamic mycelia and spores. One of the most devastating diseases of cocoa trees is caused by fungal phytopathogen Moniliophthora roreri. Strategies for pest management include the application of endophytic fungi, such as Trichoderma harzianum, that act as biocontrol agents by antagonizing M. roreri. However, the complex chemical communication underlying the basis for this phytopathogen-dependent biocontrol is still unknown. In this study, we investigated the metabolic exchange that takes place during the antagonistic interaction between M. roreri and T. harzianum. Using imprint-DESI-MS imaging we annotated the secondary metabolites released when T. harzianum and M. roreri were cultured in isolation and compared these to those produced after 3 weeks of coculture. We identified and localized four phytopathogen-dependent secondary metabolites, including T39 butenolide, harzianolide, and sorbicillinol. In order to verify the reliability of the imprint-DESI-MS imaging data and evaluate the capability of tape imprints to extract fungal metabolites while maintaining their localization, six representative plugs along the entire M. roreri/T. harzianum

  16. An automatic pellet dispenser for precise control of feeding topography in granivorous birds

    PubMed Central

    Berkhoudt, H.; Van Der Reijden, D.; Heijmans, M.

    1987-01-01

    Design and construction of an automatic pellet dispenser for granivorous birds are described. The dispenser permits rapid pneumatic delivery of pellets (five pellets per second maximum) to one controlled position and does not interfere with simultaneous electrophysiological recording. In addition, the device continuously indicates presence or absence of a pellet in the delivery position. This automatic dispenser proved very effective in our studies of stereotyped topographies of feeding in granivorous birds, such as pigeons and chickens. PMID:16812503

  17. Characterization of Fe/KClO4 heat powders and pellets.

    SciTech Connect

    Reinhardt, Frederick William; Guidotti, Ronald Armand; Odinek, Judy Gail

    2005-04-01

    Pellets of Fe/KClO{sub 4} mixtures are used as a heat source for thermally activated ('thermal') batteries. They provide the energy necessary for melting the electrolyte and bringing the battery stack to operating temperature. The effects of morphology of the Fe and the heat-pellet density and composition on both the physical properties (flowability, pelletization, and pellet strength) and the pyrotechnic performance (burn rate and ignition sensitivity) were examined using several commercial sources of Fe.

  18. Pellet fabrication development using thermally denitrated UO sub 2 powder

    SciTech Connect

    Davis, N.C.; Griffin, C.W.

    1992-05-01

    Pacific Northwest Laboratory (PNL) has evaluted, on a laboratory scale, the characteristics and pellet fabrication properties of UO{sub 3} powder prepared by the thermal denitration process. Excellent quality, 96% TD (percent of theoretical density) pellets were produced from development lots of this powder. Apparently, the key to making this highly sinterable powder from uranyl nitrate is the addition of ammonium nitrate (NH{sub 4}NO{sub 3}) to the feed solution prior to thermal denitration. Powder lots were processed with and without the NH{sub 4}NO{sub 3} addition in the feed solution. The lots included samples from the ORNL laboratory rotary kiln and from a larger scale rotary kiln at National Lead of Ohio (NLO). In the PNL evaluation, samples of UO{sub 3} were calculated and reduced to UO{sub 2}, followed by conventional process procedures to compare the sinterability of the powder lots. The high density pellets made from the powder lots, which included the NH{sub 4}NO{sub 3} addition, were reduced to Fast Breeder Reactor (FBR) density range of 88 to 92% TD by the use of poreformers. The NH{sub 4}NO{sub 3} addition also improved the sinterability properties of uranium oxide powders that contain thorium and cerium. Thorium and cerium were used as stand-in'' for plutonium used in urania-plutonia FBR fuel pellets. A very preliminary examination of a single lot of thermally denitrated uranium-plutonium oxide powder was made. This powder lot was made with the NH{sub 3}NO{sub 3} addition and produced pellets just above the FBR density range.

  19. Lightning arrestor connector lead magnesium niobate qualification pellet test procedures.

    SciTech Connect

    Tuohig, W.; Mahoney, Patrick A.; Tuttle, Bruce Andrew; Wheeler, Jill Susanne

    2009-02-01

    Enhanced knowledge preservation for DOE DP technical component activities has recently received much attention. As part of this recent knowledge preservation effort, improved documentation of the sample preparation and electrical testing procedures for lead magnesium niobate--lead titanate (PMN/PT) qualification pellets was completed. The qualification pellets are fabricated from the same parent powders used to produce PMN/PT lightning arrestor connector (LAC) granules at HWF&T. In our report, the procedures for fired pellet surface preparation, electrode deposition, electrical testing and data recording are described. The dielectric measurements described in our report are an information only test. Technical reasons for selecting the electrode material, electrode size and geometry are presented. The electrical testing is based on measuring the dielectric constant and dissipation factor of the pellet during cooling from 280 C to 220 C. The most important data are the temperature for which the peak dielectric constant occurs (Curie Point temperature) and the peak dielectric constant magnitude. We determined that the peak dielectric constant for our procedure would be that measured at 1 kHz at the Curie Point. Both the peak dielectric constant and the Curie point parameters provide semi-quantitative information concerning the chemical and microstructural homogeneity of the parent material used for the production of PMN/PT granules for LACs. Finally, we have proposed flag limits for the dielectric data for the pellets. Specifically, if the temperature of the peak dielectric constant falls outside the range of 250 C {+-} 30 C we propose that a flag limit be imposed that will initiate communication between production agency and design agency personnel. If the peak dielectric constant measured falls outside the range 25,000 {+-} 10,000 we also propose that a flag limit be imposed.

  20. Intertrial Pellets Influence the Acquisition and Expression of Timed Appetitive Responding in Rats

    ERIC Educational Resources Information Center

    Williams, Douglas A.; Lussier, April L.

    2011-01-01

    Two experiments examined temporally based changes in the conditioned magazine-entries of rats when a target food pellet arrived at a fixed time before the termination of a conditioned stimulus. Both experiments found that increasing the rate of intertrial pellets systematically interfered with the rate of acquisition. When intertrial pellets were…

  1. Remote Visual Inspection Of Nuclear Fuel Pellets With Fiber Optics And Video Image Processing

    NASA Astrophysics Data System (ADS)

    Moore, Frank W.

    1985-12-01

    Westinghouse Hanford Company has designed and is constructing a nuclear fuel fabrication process line for the Department of Energy. This process line includes a pellet surface inspection system that remotely inspects the cylindrical surface of nuclear fuel pellets for surface spots, flaws, or discoloration. The pellets are inspected on a 100 percent basis after pellet sintering. A feeder will deliver the pellets directly to a fiber optic inspection head. The inspection head will view one pellet surface at a time. The surface image of the pellet will be imaged to a closed-circuit color television camera (CCTV). The output signal of the CCTV will be input to a digital imaging processor that stores approximately 25 pellet images at a time. A human operator will visually examine the images of the pellet surfaces on a high resolution monitor and accept or reject the pellets based on visual standards. The operator will use a digitizing tablet to record the location of rejected pellets, which will then be automatically removed from the product stream. The system is expandable to automated disposition of the pellet surface image.

  2. Efficacy and persistence of Altosid pellets against Culex species in catch basins in Michigan.

    PubMed

    McCarry, M J

    1996-03-01

    Larvae of Culex pipiens and Cx. restuans in catch basins were exposed to Altosid pellets (4% active ingredient, [S]-methoprene) applied at a rate of 11.3 kg/ha (7 g of pellets per catch basin). Under field conditions, the pellets yielded an average 82% emergence inhibition of adult mosquitoes over the 15-wk trial period.

  3. Role of prereduced pellets in the slag foaming in modern EAFs

    NASA Astrophysics Data System (ADS)

    Kozhukhov, A. A.

    2013-06-01

    The problems of electric arc furnace slags are considered, and the role of prereduced pellets in the slag foaming in electric arc furnaces is studied. The optimum rate of loading of prereduced pellets into a furnace that ensures effective steelmaking slag foaming is determined as a function of the degree of pellet prereduction.

  4. Reuse potential of low-calcium bottom ash as aggregate through pelletization.

    PubMed

    Geetha, S; Ramamurthy, K

    2010-01-01

    Coal combustion residues which include fly ash, bottom ash and boiler slag is one of the major pollutants as these residues require large land area for their disposal. Among these residues, utilization of bottom ash in the construction industry is very low. This paper explains the use of bottom ash through pelletization. Raw bottom ash could not be pelletized as such due to its coarseness. Though pulverized bottom ash could be pelletized, the pelletization efficiency was low, and the aggregates were too weak to withstand the handling stresses. To improve the pelletization efficiency, different clay and cementitious binders were used with bottom ash. The influence of different factors and their interaction effects were studied on the duration of pelletization process and the pelletization efficiency through fractional factorial design. Addition of binders facilitated conversion of low-calcium bottom ash into aggregates. To achieve maximum pelletization efficiency, the binder content and moisture requirements vary with type of binder. Addition of Ca(OH)(2) improved the (i) pelletization efficiency, (ii) reduced the duration of pelletization process from an average of 14-7 min, and (iii) reduced the binder dosage for a given pelletization efficiency. For aggregate with clay binders and cementitious binder, Ca(OH)(2) and binder dosage have significant effect in reducing the duration of pelletization process. PMID:20400282

  5. Particle confinement of pellet-fuelled H-mode plasmas in the Mega Ampere Spherical Tokamak

    NASA Astrophysics Data System (ADS)

    Valovič, M.; Axon, K.; Garzotti, L.; Saarelma, S.; Thyagaraja, A.; Akers, R.; Gurl, C.; Kirk, A.; Lloyd, B.; Maddison, G. P.; Patel, A.; Shibaev, S.; Scannell, R.; Taylor, D.; Walsh, M.; MAST Team

    2008-07-01

    This paper quantifies the particle confinement of pellet-fuelled plasmas in the Mega Ampere Spherical Tokamak (MAST). The dataset is restricted mostly to neutral beam heated plasmas and to shallow pellets launched from the high field side. It is shown that the pellet deposition can be explained only by invoking the ∇B drift of the pellet ablatant. The pellet creates a zone with positive density gradient and increased temperature gradient. Simulations show that these changes could increase the level of micro-turbulence and thus enhance further the penetration of pellet-deposited particles towards the core. Post-pellet dynamics of the density profile is characterised by the pellet retention time τpel. It is shown that τpel correlates with the status of the edge transport barrier (L-mode or H-mode) and decreases rapidly for pellet deposition radius rpel approaching the plasma edge. For ELMy H-mode and ITER-like pellets, rpel ≈ 0.8a, the pellet retention time is about 20% of the energy confinement time. The fuelling requirement by the pellets for ITER is discussed.

  6. Bio-prospecting of distillery yeasts as bio-control and bio-remediation agents.

    PubMed

    Ubeda, Juan F; Maldonado, María; Briones, Ana I; Francisco, J Fernández; González, Francisco J

    2014-05-01

    This work constitutes a preliminary study in which the capacity of non-Saccharomyces yeasts isolated from ancient distilleries as bio-control agents against moulds and in the treatment of waste waters contaminated by heavy metals-i.e. bio-remediation-is shown. In the first control assays, antagonist effect between non-Saccharomyces yeasts, their extracts and supernatants against some moulds, analysing the plausible (not exhaustive) involved factors were qualitatively verified. In addition, two enzymatic degrading properties of cell wall plant polymers, quitinolitic and pectinolitic, were screened. Finally, their use as agents of bio-remediation of three heavy metals (cadmium, chromium and lead) was analysed semi-quantitatively. The results showed that all isolates belonging to Pichia species effectively inhibited all moulds assayed. Moreover, P. kudriavzevii is a good candidate for both bio-control and bio-remediation because it inhibited moulds and accumulated the major proportion of the three tested metals. PMID:24370629

  7. Bio-prospecting of distillery yeasts as bio-control and bio-remediation agents.

    PubMed

    Ubeda, Juan F; Maldonado, María; Briones, Ana I; Francisco, J Fernández; González, Francisco J

    2014-05-01

    This work constitutes a preliminary study in which the capacity of non-Saccharomyces yeasts isolated from ancient distilleries as bio-control agents against moulds and in the treatment of waste waters contaminated by heavy metals-i.e. bio-remediation-is shown. In the first control assays, antagonist effect between non-Saccharomyces yeasts, their extracts and supernatants against some moulds, analysing the plausible (not exhaustive) involved factors were qualitatively verified. In addition, two enzymatic degrading properties of cell wall plant polymers, quitinolitic and pectinolitic, were screened. Finally, their use as agents of bio-remediation of three heavy metals (cadmium, chromium and lead) was analysed semi-quantitatively. The results showed that all isolates belonging to Pichia species effectively inhibited all moulds assayed. Moreover, P. kudriavzevii is a good candidate for both bio-control and bio-remediation because it inhibited moulds and accumulated the major proportion of the three tested metals.

  8. Measurement of Persistent Organic Pollutants (POPs) in plastic resin pellets from remote islands : Toward establishment of baseline level for International Pellet Watch

    NASA Astrophysics Data System (ADS)

    Takada, H.; Heskett, M.; Yamashita, R.; Yuyama, M.; Itoh, M.; Geok, Y. B.; Ogata, Y.

    2011-12-01

    Plastic resin pellets collected from remote islands in open oceans (Canary, St. Helena, Cocos, Hawaii, Maui Islands and Barbados) were sorted and yellowing polyethylene (PE) pellets were measured for polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and the degradation products (DDTs), and hexachlorocyclohexanes (HCHs) by gas chromatograph equipped with mass spectrometer (GC-MS) and with electron capture detector (GC-ECD). PCBs were detected from all the pellet samples, confirming the global dispersion of PCBs. Median concentrations of PCBs (sum of 13 congeners : CB-66, CB-101, CB-110, CB-118, CB-105, CB-149, CB-153, CB-138, CB-128, CB-187, CB-180, CB-170, CB-206) in the remote island pellets ranged from 0.1 to 10 ng/g-pellet. These were one to three orders of magnitude lower than those observed for pellets from industrialized coastal zones (hundreds ng/g in Los Angeles, Boston, Tokyo; Ogata et al., 2009). Because these remote islands are far (>100 km) from industrialized zones, these concentrations (i.e., 0.1 to 10 ng/g-pellet) can be regarded as global "baseline" level of PCB pollution. Concentrations of DDTs in the remote island pellets ranged from 0.2 to 5.5 ng/g-pellet. At some locations, DDT was dominant over the degradation products (DDE and DDD), suggesting current usage of the pesticides in the islands. HCHs concentrations were 0.4 - 1.8 ng/g-pellet and lower than PCBs and DDTs, except for St. Helena Island at 18.8 ng/g-pellet where the current usage of the pesticides are of concern. The analyses of pellets from the remote islands provided "baseline" level of POPs (PCBs < 10 ng/g-pellet, DDTs < 6 ng/g-pellet, HCHs < 2 ng/g-pellet). However, the present samples were from tropical and subtropical areas. To establish global baseline, especially to understand the effects of global distillation, pellet samples from remote islands in higher latitude regions are necessary. From the eco-toxicological point of view, the fact that sporadic high

  9. Complete Genome Sequence of the Endophytic Biocontrol Strain Bacillus velezensis CC09

    PubMed Central

    Cai, Xunchao; Kang, Xingxing; Xi, Huan

    2016-01-01

    Bacillus velezensis is a heterotypic synonym of B. methylotrophicus, B. amyloliquefaciens subsp. plantarum, and Bacillus oryzicola, and has been used to control plant fungal diseases. In order to fully understand the genetic basis of antimicrobial capacities, we did a complete genome sequencing of the endophytic B. velezensis strain CC09. Genes tightly associated with biocontrol ability, including nonribosomal peptide synthetases, polyketide synthetases, iron acquisition, colonization, and volatile organic compound synthesis were identified in the genome. PMID:27688342

  10. Complete Genome Sequence of the Endophytic Biocontrol Strain Bacillus velezensis CC09.

    PubMed

    Cai, Xunchao; Kang, Xingxing; Xi, Huan; Liu, Changhong; Xue, Yarong

    2016-01-01

    Bacillus velezensis is a heterotypic synonym of B. methylotrophicus, B. amyloliquefaciens subsp. plantarum, and Bacillus oryzicola, and has been used to control plant fungal diseases. In order to fully understand the genetic basis of antimicrobial capacities, we did a complete genome sequencing of the endophytic B. velezensis strain CC09. Genes tightly associated with biocontrol ability, including nonribosomal peptide synthetases, polyketide synthetases, iron acquisition, colonization, and volatile organic compound synthesis were identified in the genome. PMID:27688342

  11. Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes

    PubMed Central

    Landis, Douglas A.; Gardiner, Mary M.; van der Werf, Wopke; Swinton, Scott M.

    2008-01-01

    Increased demand for corn grain as an ethanol feedstock is altering U.S. agricultural landscapes and the ecosystem services they provide. From 2006 to 2007, corn acreage increased 19% nationally, resulting in reduced crop diversity in many areas. Biological control of insects is an ecosystem service that is strongly influenced by local landscape structure. Here, we estimate the value of natural biological control of the soybean aphid, a major pest in agricultural landscapes, and the economic impacts of reduced biocontrol caused by increased corn production in 4 U.S. states (Iowa, Michigan, Minnesota, and Wisconsin). For producers who use an integrated pest management strategy including insecticides as needed, natural suppression of soybean aphid in soybean is worth an average of $33 ha−1. At 2007–2008 prices these services are worth at least $239 million y−1 in these 4 states. Recent biofuel-driven growth in corn planting results in lower landscape diversity, altering the supply of aphid natural enemies to soybean fields and reducing biocontrol services by 24%. This loss of biocontrol services cost soybean producers in these states an estimated $58 million y−1 in reduced yield and increased pesticide use. For producers who rely solely on biological control, the value of lost services is much greater. These findings from a single pest in 1 crop suggest that the value of biocontrol services to the U.S. economy may be underestimated. Furthermore, we suggest that development of cellulosic ethanol production processes that use a variety of feedstocks could foster increased diversity in agricultural landscapes and enhance arthropod-mediated ecosystem services. PMID:19075234

  12. Rust fungi and global change.

    PubMed

    Helfer, Stephan

    2014-02-01

    Rust fungi are important components of ecological communities and in ecosystem function. Their unique life strategies as biotrophic pathogens with complicated life cycles could make them vulnerable to global environmental change. While there are gaps in our knowledge, especially in natural plant–rust systems, this review of the exposure of rust fungi to global change parameters revealed that some host–rust relationships would decline under predicted environmental change scenarios, whereas others would either remain unchanged or become more prevalent. Notably, some graminicolous rusts are negatively affected by higher temperatures and increased concentrations of atmospheric CO2. An increase of atmospheric O3 appears to favour rust diseases on trees but not those on grasses. Combined effects of CO2 and O3 are intermediary. The most important global drivers for the geographical and host plant range expansion and prevalence of rusts, however, are global plant trade, host plant genetic homogenization and the regular occurrence of conducive environmental conditions, especially the availability of moisture. However, while rusts thrive in high-humidity environments, they can also survive in desert habitats, and as a group their environmental tolerance is large, with no conclusive change in their overall prevalence predictable to date.

  13. Bioprospecting--fuels from fungi.

    PubMed

    Strobel, Gary Allan

    2015-05-01

    The world has a continuing demand and utility for liquid fuels to power its societies. The utilization of crude oil based fuels is leading to a dramatic increase in the CO2 content of the atmosphere which is being related to a dangerously warming earth. Having liquid fuels that are derived from biological sources is one solution to this growing problem since the carbon being utilized is only from recycled sources. Presently, the microbes, having the greatest impact on the world's economies, producing liquid fuel are various yeasts producing ethanol. Other microbial sources need to be sought since ethanol is not the most desirable fuel and yeasts require simple sugars to carry out the fermentation processes. Recently, several endophytic fungi have been described that make hydrocarbons with fuel potential (Mycodiesel). Among others the compounds found in the volatile phases of these cultures include alkanes, branched alkanes, cyclohexanes, cyclopentanes, and alkyl alcohols/ketones, benzenes and polyaromatic hydrocarbons. Most importantly, generally these organisms make hydrocarbons while utilizing complex carbohydrates found in all plant-based agricultural wastes. Also discussed in this review is a rationale for finding hydrocarbon producing endophytes as well as examples of other promising hydrocarbon producers-Nodulisporium spp. which make 1,8-cineole and families of other hydrocarbons. Extremely favorable results of engine and fuel testing experiments recently completed on cineole and other products of Nodulisporium sp. are also presented. Finally, there is a brief discussion on the main limiting steps in the domestication of these fungi.

  14. Fungi: the neglected allergenic sources.

    PubMed

    Crameri, R; Garbani, M; Rhyner, C; Huitema, C

    2014-02-01

    Allergic diseases are considered the epidemics of the twentieth century estimated to affect more than 30% of the population in industrialized countries with a still increasing incidence. During the past two decades, the application of molecular biology allowed cloning, production and characterization of hundreds of recombinant allergens. In turn, knowledge about molecular, chemical and biologically relevant allergens contributed to increase our understanding of the mechanisms underlying IgE-mediated type I hypersensitivity reactions. It has been largely demonstrated that fungi are potent sources of allergenic molecules covering a vast variety of molecular structures including enzymes, toxins, cell wall components and phylogenetically highly conserved cross-reactive proteins. Despite the large knowledge accumulated and the compelling evidence for an involvement of fungal allergens in the pathophysiology of allergic diseases, fungi as a prominent source of allergens are still largely neglected in basic research as well as in clinical practice. This review aims to highlight the impact of fungal allergens with focus on asthma and atopic dermatitis.

  15. Toxigenic fungi: which are important?

    PubMed

    Pitt, J I

    2000-01-01

    Growth of commonly occurring filamentous fungi in foods may result in production of mycotoxins, which can cause a variety of ill effects in humans, from allergic responses to immunosuppression and cancer. According to experts, five kinds of mycotoxins are important in human health around the world: aflatoxins, ochratoxin A, fumonisins, certain trichothecenes, and zearalenone. These toxins are produced by only a few species of fungi, in a limited range of commodities. Aflatoxins are potent carcinogens, produced by Aspergillus flavus and A. parasiticus in peanuts, maize and some other nuts and oilseeds. Ochratoxin A is a kidney toxin and probable carcinogen. It is produced by Penicillium verrucosum in cereal grains in cold climates, by A. carbonarius in grapes, wines and vine fruits, and by A. ochraceus sometimes in coffee beans. Fumonisins, which may cause oesophageal cancer, are formed by Fusarium moniliforme and F. proliferatum, but only in maize. Trichothecenes are highly immunosuppressive and zearalenone causes oestrogenic effects; both are produced by F. graminearum and related species. Current reporting probably underestimates the effect of mycotoxins as a cause of human mortality. PMID:11204142

  16. Fungi, Water Supply and Biofilms.

    PubMed

    Kauffmann-Lacroix, Catherine; Costa, Damien; Imbert, Christine

    2016-01-01

    Even though it has been studied for many years, water-related infectious risk still exists in both care and community environments due to the possible presence of numerous microorganisms such as bacteria, fungi and protists. People can be exposed directly to these microorganisms either through aerosols and water, after ingestion, inhalation, skin contact and entry through mucosal membranes, or indirectly usually due to pre-treatment of some medical devices. Species belonging to genera such as Aspergillus, Penicillium, Pseudallesheria, Fusarium, Cuninghamella, Mucor and in some particular cases Candida have been isolated in water from health facilities and their presence is particularly related to the unavoidable formation of a polymicrobial biofilm in waterlines. Fungi isolation methods are based on water filtration combined with conventional microbiology cultures and/or molecular approaches; unfortunately, these are still poorly standardized. Moreover, due to inappropriate culture media and inadequate sampling volumes, the current standardized methods used for bacterial research are not suitable for fungal search. In order to prevent water-related fungal risk, health facilities have implemented measures such as ultraviolet radiation to treat the input network, continuous chemical treatment, chemical or thermal shock treatments, or microfiltration at points of use. This article aims to provide an overview of fungal colonization of water (especially in hospitals), involvement of biofilms that develop in waterlines and application of preventive strategies. PMID:27167410

  17. Fungi, Water Supply and Biofilms.

    PubMed

    Kauffmann-Lacroix, Catherine; Costa, Damien; Imbert, Christine

    2016-01-01

    Even though it has been studied for many years, water-related infectious risk still exists in both care and community environments due to the possible presence of numerous microorganisms such as bacteria, fungi and protists. People can be exposed directly to these microorganisms either through aerosols and water, after ingestion, inhalation, skin contact and entry through mucosal membranes, or indirectly usually due to pre-treatment of some medical devices. Species belonging to genera such as Aspergillus, Penicillium, Pseudallesheria, Fusarium, Cuninghamella, Mucor and in some particular cases Candida have been isolated in water from health facilities and their presence is particularly related to the unavoidable formation of a polymicrobial biofilm in waterlines. Fungi isolation methods are based on water filtration combined with conventional microbiology cultures and/or molecular approaches; unfortunately, these are still poorly standardized. Moreover, due to inappropriate culture media and inadequate sampling volumes, the current standardized methods used for bacterial research are not suitable for fungal search. In order to prevent water-related fungal risk, health facilities have implemented measures such as ultraviolet radiation to treat the input network, continuous chemical treatment, chemical or thermal shock treatments, or microfiltration at points of use. This article aims to provide an overview of fungal colonization of water (especially in hospitals), involvement of biofilms that develop in waterlines and application of preventive strategies.

  18. Oxidative stress in industrial fungi.

    PubMed

    Li, Qiang; Harvey, Linda M; McNeil, Brian

    2009-01-01

    Fungi are amongst the most industrially important microorganisms in current use within the biotechnology industry. Most such fungal cultures are highly aerobic in nature, a character that has been frequently referred to in both reactor design and fungal physiology. The most fundamentally significant outcome of the highly aerobic growth environment in fermenter vessels is the need for the fungal culture to effectively combat in the intracellular environment the negative consequences of high oxygen transfer rates. The use of oxygen as the respiratory substrate is frequently reported to lead to the development of oxidative stress, mainly due to oxygen-derived free radicals, which are collectively termed as reactive oxygen species (ROS). Recently, there has been extensive research on the occurrence, extent, and consequences of oxidative stress in microorganisms, and the underlying mechanisms through which cells prevent and repair the damage caused by ROS. In the present study, we critically review the current understanding of oxidative stress events in industrially relevant fungi. The review first describes the current state of knowledge of ROS concisely, and then the various antioxidant strategies employed by fungal cells to counteract the deleterious effects, together with their implications in fungal bioprocessing are also discussed. Finally, some recommendations for further research are made. PMID:19514862

  19. Statistical media optimization for the biomass production of postharvest biocontrol yeast Rhodosporidium paludigenum.

    PubMed

    Wang, Peng; Liu, Xia; Wang, Yifei; Ruan, Hui; Zheng, XiaoDong

    2011-01-01

    A cane molasses-based medium for the biomass production of biocontrol agent Rhodosporidium paludigenum was statistically optimized. Molasses concentration (after pretreatment), yeast extract, and initial pH were identified by the Plackett-Burman design to show significant influence on the biomass production. The three factors were further optimized by central composite design and response-surface methodology. The statistical analysis indicated the optimum values of the variables were 89.98 g/L for cane molasses, 2.35 g/L for yeast extract and an initial pH of 8.48. The biomass yield at the optimal culture achieved 15.89 g/L in flask fermentation, which was 2.1 times higher than that at the initial NYDB medium. In a 10-L fermenter, 18.97 g/L of biomass was obtained after 36 hr of cultivation. Moreover, the biocontrol efficacy of the yeast was investigated after culture optimization. The results showed the yeast harvested in the optimal medium maintained its initial biocontrol properties by reducing the percentage of decayed apples to below 20%.

  20. Mechanism of H₂O₂-induced oxidative stress regulating viability and biocontrol ability of Rhodotorula glutinis.

    PubMed

    Chen, Jian; Li, Boqiang; Qin, Guozheng; Tian, Shiping

    2015-01-16

    The use of antagonistic yeasts to control postharvest pathogens is a promising alternative to fungicides. The effectiveness of the antagonists against fungal pathogens is greatly dependent on their viability, which is usually mediated by reactive oxygen species (ROS). Here, we investigated the effects of H₂O₂-induced oxidative stress on the viability and biocontrol efficacy of Rhodotorula glutinis and, using flow cytometric analysis, observed the changes of ROS accumulation and apoptosis in the yeast cells with or without H₂O₂ treatment. We found that the viability of R. glutinis decreased in a time- and dose-dependent manner under H₂O₂-induced oxidative stress. Compared to the control, yeast cells exposed to oxidative stress exhibited more accumulation of ROS and higher levels of protein oxidative damage, but showed lower efficacy for biocontrol of Penicillium expansum causing blue mold rot on peach fruit. The results indicate that apoptosis is a main cause of the cell viability loss in R. glutinis, which is attributed to ROS accumulation under oxidative stress. These findings offer a plausible explanation that oxidative stress affects biocontrol efficacy of R. glutinis via regulating its viability and cell apoptosis.

  1. Isolation of Dickeya dadantii strains from potato disease and biocontrol by their bacteriophages

    PubMed Central

    Soleimani-Delfan, Abbas; Etemadifar, Zahra; Emtiazi, Giti; Bouzari, Majid

    2015-01-01

    One of the most economically important bacterial pathogens of plants and plant products is Dickeya dadantii. This bacterium causes soft rot disease in tubers and other parts of the potato and other plants of the Solanaceae family. The application of restricted host range bacteriophages as biocontrol agents has recently gained widespread interest. This study purposed to isolate the infectious agent of the potato and evaluate its biocontrol by bacteriophages. Two phytopathogenic strains were isolated from infected potatoes, identified based on biochemical and 16S rRNA gene sequencing, and submitted to GenBank as D. dadantii strain pis3 (accession no. HQ423668) and D. dadantii strain sip4 (accession no. HQ423669). Their bacteriophages were isolated from Caspian Sea water by enriching the water filtrate with D. dadantii strains as hosts using spot or overlay methods. On the basis of morphotypes, the isolated bacteriophages were identified as members of the Myoviridae and Siphoviridae families and could inhibit the growth of antibiotic resistant D. dadantii strains in culture medium. Moreover, in Dickeya infected plants treated with bacteriophage, no disease progression was detected. No significant difference was seen between phage-treated and control plants. Thus, isolated bacteriophages can be suggested for the biocontrol of plant disease caused by Dickeya strains. PMID:26413062

  2. Isolation of Dickeya dadantii strains from potato disease and biocontrol by their bacteriophages.

    PubMed

    Soleimani-Delfan, Abbas; Etemadifar, Zahra; Emtiazi, Giti; Bouzari, Majid

    2015-01-01

    One of the most economically important bacterial pathogens of plants and plant products is Dickeya dadantii. This bacterium causes soft rot disease in tubers and other parts of the potato and other plants of the Solanaceae family. The application of restricted host range bacteriophages as biocontrol agents has recently gained widespread interest. This study purposed to isolate the infectious agent of the potato and evaluate its biocontrol by bacteriophages. Two phytopathogenic strains were isolated from infected potatoes, identified based on biochemical and 16S rRNA gene sequencing, and submitted to GenBank as D. dadantii strain pis3 (accession no. HQ423668) and D. dadantii strain sip4 (accession no. HQ423669). Their bacteriophages were isolated from Caspian Sea water by enriching the water filtrate with D. dadantii strains as hosts using spot or overlay methods. On the basis of morphotypes, the isolated bacteriophages were identified as members of the Myoviridae and Siphoviridae families and could inhibit the growth of antibiotic resistant D. dadantii strains in culture medium. Moreover, in Dickeya infected plants treated with bacteriophage, no disease progression was detected. No significant difference was seen between phage-treated and control plants. Thus, isolated bacteriophages can be suggested for the biocontrol of plant disease caused by Dickeya strains.

  3. Potential of Pseudomonas chlororaphis subsp. aurantiaca Strain Pcho10 as a Biocontrol Agent Against Fusarium graminearum.

    PubMed

    Hu, Weiqun; Gao, Qixun; Hamada, Mohamed Sobhy; Dawood, Dawood Hosni; Zheng, Jingwu; Chen, Yun; Ma, Zhonghua

    2014-12-01

    To develop an effective biocontrol strategy for management of Fusarium head blight on wheat caused by Fusarium graminearum, the bacterial biocontrol agent Pcho10 was selected from more than 1,476 wheat-head-associated bacterial strains according to its antagonistic activity in vitro. This strain was subsequently characterized as Pseudomonas chlororaphis subsp. aurantiaca based on 16S ribosomal DNA sequence analysis, assays of the BIOLOG microbial identification system, and unique pigment production. The major antifungal metabolite produced by Pcho10 was further identified as phenazine-1-carboxamide (PCN) on the basis of nuclear magnetic resonance data. The core PCN biosynthesis gene cluster in Pcho10 was cloned and sequenced. PCN showed strong inhibitory activity against F. graminearum conidial germination, mycelial growth, and deoxynivalenol production. Tests both under growth chamber conditions and in field trials showed that Pcho10 well colonized on the wheat head and effectively controlled the disease caused by F. graminearum. Results of this study indicate that P. chlororaphis subsp. aurantiaca Pcho10 has high potential to be developed as a biocontrol agent against F. graminearum. To our knowledge, this is the first report of the use of P. chlororaphis for the management of Fusarium head blight.

  4. Combined use of biocontrol agents to manage plant diseases in theory and practice.

    PubMed

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

    2011-09-01

    Effective use of biological control agents (BCAs) is a potentially important component of sustainable agriculture. Recently, there has been an increasing interest among researchers in using combinations of BCAs to exploit potential synergistic effects among them. The methodology for investigating such synergistic effects was reviewed first and published results were then assessed for available evidence for synergy. Correct formulation of hypotheses based on the theoretical definition of independence (Bliss independence or Loewe additivity) and the subsequent and statistical testing for the independence-synergistic-antagonistic interactions have rarely been carried out thus far in studies on biocontrol of plant diseases. Thus, caution must be taken when interpreting reported "synergistic" effects without assessing the original publications. Recent theoretical modeling work suggested that disease suppression from combined use of two BCAs was, in general, very similar to that achieved by the more efficacious one, indicating no synergistic but more likely antagonistic interactions. Only in 2% of the total 465 published treatments was there evidence for synergistic effects among BCAs. In the majority of the cases, antagonistic interactions among BCAs were indicated. Thus, both theoretical and experimental studies suggest that, in combined use of BCAs, antagonistic interactions among BCAs are more likely to occur than synergistic interactions. Several research strategies, including formulation of synergy hypotheses in relation to biocontrol mechanisms, are outlined to exploit microbial mixtures for uses in biocontrol of plant diseases.

  5. Use of mixed cultures of biocontrol agents to control sheep nematodes.

    PubMed

    Baloyi, M A; Laing, M D; Yobo, K S

    2012-03-23

    Biological control is a promising non-chemical approach for the control of gastrointestinal nematodes of sheep. Use of combinations of biocontrol agents have been reported to be an effective method to increase the efficacy of biological control effects. In this study, combinations of either two Bacillus thuringiensis (Bt) or Clonostachys rosea (C. rosea) isolates and Bt+C. rosea isolates were evaluated in vitro in microtitre plates for their biocontrol activity on sheep nematodes. The Baermann technique was used to extract the surviving L3 larval stages of intestinal nematodes and counted under a dissecting microscope to determine the larval counts. Results indicate that there was a significant reduction of nematode counts due to combination of biocontrol agents (P<0.001). Combinations of Bt isolates reduced nematodes counts by 72.8%, 64% and 29.8%. The results revealed a control level of 57% when C. rosea isolates P3+P8 were combined. Combination of Bt and C. rosea isolates B10+P8 caused the greatest mortality of 76.7%. Most combinations were antagonistic, with only a few combinations showing an additive effect. None were synergistic. The isolate combinations were more effective than when isolates were used alone.

  6. Potential of Pseudomonas chlororaphis subsp. aurantiaca Strain Pcho10 as a Biocontrol Agent Against Fusarium graminearum.

    PubMed

    Hu, Weiqun; Gao, Qixun; Hamada, Mohamed Sobhy; Dawood, Dawood Hosni; Zheng, Jingwu; Chen, Yun; Ma, Zhonghua

    2014-12-01

    To develop an effective biocontrol strategy for management of Fusarium head blight on wheat caused by Fusarium graminearum, the bacterial biocontrol agent Pcho10 was selected from more than 1,476 wheat-head-associated bacterial strains according to its antagonistic activity in vitro. This strain was subsequently characterized as Pseudomonas chlororaphis subsp. aurantiaca based on 16S ribosomal DNA sequence analysis, assays of the BIOLOG microbial identification system, and unique pigment production. The major antifungal metabolite produced by Pcho10 was further identified as phenazine-1-carboxamide (PCN) on the basis of nuclear magnetic resonance data. The core PCN biosynthesis gene cluster in Pcho10 was cloned and sequenced. PCN showed strong inhibitory activity against F. graminearum conidial germination, mycelial growth, and deoxynivalenol production. Tests both under growth chamber conditions and in field trials showed that Pcho10 well colonized on the wheat head and effectively controlled the disease caused by F. graminearum. Results of this study indicate that P. chlororaphis subsp. aurantiaca Pcho10 has high potential to be developed as a biocontrol agent against F. graminearum. To our knowledge, this is the first report of the use of P. chlororaphis for the management of Fusarium head blight. PMID:24941327

  7. Statistical media optimization for the biomass production of postharvest biocontrol yeast Rhodosporidium paludigenum.

    PubMed

    Wang, Peng; Liu, Xia; Wang, Yifei; Ruan, Hui; Zheng, XiaoDong

    2011-01-01

    A cane molasses-based medium for the biomass production of biocontrol agent Rhodosporidium paludigenum was statistically optimized. Molasses concentration (after pretreatment), yeast extract, and initial pH were identified by the Plackett-Burman design to show significant influence on the biomass production. The three factors were further optimized by central composite design and response-surface methodology. The statistical analysis indicated the optimum values of the variables were 89.98 g/L for cane molasses, 2.35 g/L for yeast extract and an initial pH of 8.48. The biomass yield at the optimal culture achieved 15.89 g/L in flask fermentation, which was 2.1 times higher than that at the initial NYDB medium. In a 10-L fermenter, 18.97 g/L of biomass was obtained after 36 hr of cultivation. Moreover, the biocontrol efficacy of the yeast was investigated after culture optimization. The results showed the yeast harvested in the optimal medium maintained its initial biocontrol properties by reducing the percentage of decayed apples to below 20%. PMID:21967338

  8. Wonder world of phages: potential biocontrol agents safeguarding biosphere and health of animals and humans- current scenario and perspectives.

    PubMed

    Tiwari, Ruchi; Chakraborty, Sandip; Dhama, Kuldeep; Wani, Mohd Yaqoob; Kumar, Amit; Kapoor, Sanjay

    2014-02-01

    Darwin's theory of natural selection and concept of survival of fittest of Wallace is a universal truth which derives the force of life among all live entities on this biosphere. Issues regarding food safety along with increased drug resistance and emerging zoonotic infections have proved that multidisciplinary efforts are in demand for human and animal welfare. This has led to development of various novel therapies the list of which remains incomplete without mentioning about phages. Homologous and non-homologous recombination along with point mutation and addition of new genes play role in their evolution. The rapid emergence of the antibiotic resistant strains of bacteria have created keen interest in finding necessary alternatives to check microbial infections and there comes the importance of phages. Phages kill the bacteria either by lysis or by releasing holins. Bacteriophages; the viruses that live on bacteria are nowadays considered as the best biocontrol agents. They are used as replacers of antibiotics; food industry promoter; guard of aquatic life as well as of plants; pre-slaughter treatment agents; Generally Recognized As Safe (GRAS) food additives; Typing agent of bacteria; active tool of super bug therapy; in post harvest crops and food and during post infection and also to combat intracellular pathogens viz. Mycobacteria and Mycoplasma. Cyanophages/phycophages are particularly useful in controlling blooms produced by various genera of algae and cyanobacteria. By performing centrifugation studies and based on electron microscopy certain virus like particles containing ds RNA have been confirmed as mycophages. They are well proven as threat to pathogenic fungi (both fungal hyphae and yeast). Those that infect yeasts are called zymophages. Virophages have exquisite specificity for their viral host, hence can extensively be used for genetic studies and can also act as evolutionary link. After the discovery of very first virophage till now, a total of 3

  9. Wonder world of phages: potential biocontrol agents safeguarding biosphere and health of animals and humans- current scenario and perspectives.

    PubMed

    Tiwari, Ruchi; Chakraborty, Sandip; Dhama, Kuldeep; Wani, Mohd Yaqoob; Kumar, Amit; Kapoor, Sanjay

    2014-02-01

    Darwin's theory of natural selection and concept of survival of fittest of Wallace is a universal truth which derives the force of life among all live entities on this biosphere. Issues regarding food safety along with increased drug resistance and emerging zoonotic infections have proved that multidisciplinary efforts are in demand for human and animal welfare. This has led to development of various novel therapies the list of which remains incomplete without mentioning about phages. Homologous and non-homologous recombination along with point mutation and addition of new genes play role in their evolution. The rapid emergence of the antibiotic resistant strains of bacteria have created keen interest in finding necessary alternatives to check microbial infections and there comes the importance of phages. Phages kill the bacteria either by lysis or by releasing holins. Bacteriophages; the viruses that live on bacteria are nowadays considered as the best biocontrol agents. They are used as replacers of antibiotics; food industry promoter; guard of aquatic life as well as of plants; pre-slaughter treatment agents; Generally Recognized As Safe (GRAS) food additives; Typing agent of bacteria; active tool of super bug therapy; in post harvest crops and food and during post infection and also to combat intracellular pathogens viz. Mycobacteria and Mycoplasma. Cyanophages/phycophages are particularly useful in controlling blooms produced by various genera of algae and cyanobacteria. By performing centrifugation studies and based on electron microscopy certain virus like particles containing ds RNA have been confirmed as mycophages. They are well proven as threat to pathogenic fungi (both fungal hyphae and yeast). Those that infect yeasts are called zymophages. Virophages have exquisite specificity for their viral host, hence can extensively be used for genetic studies and can also act as evolutionary link. After the discovery of very first virophage till now, a total of 3

  10. Effect of pelleting process variables on physical properties and sugar yields of ammonia fiber expansion pretreated corn stover

    SciTech Connect

    Amber N. Hoover; Jaya Shankar Tumuluru; Farzaneh Teymouri; Garold L. Gresham; Janette Moore

    2014-07-01

    Pelletization process variables including grind size (4, 6 mm), die speed (40, 50, 60 Hz), and preheating (none, 70 degrees C) were evaluated to understand their effect on pellet quality attributes and sugar yields of ammonia fiber expansion (AFEX) pretreated biomass. The bulk density of the pelletized AFEX corn stover was three to six times greater compared to untreated and AFEX-treated corn stover. Also the durability of the pelletized AFEX corn stover was >97.5% for all pelletization conditions studied except for preheated pellets. Die speed had no effect on enzymatic hydrolysis sugar yields of pellets. Pellets produced with preheating or a larger grind size (6 mm) had similar or lower sugar yields. Pellets generated with 4 mm AFEX-treated corn stover, a 60 Hz die speed, and no preheating resulted in pellets with similar or greater density, durability, and sugar yields compared to other pelletization conditions.

  11. Effect of pelleting process variables on physical properties and sugar yields of ammonia fiber expansion pretreated corn stover.

    PubMed

    Hoover, Amber N; Tumuluru, Jaya Shankar; Teymouri, Farzaneh; Moore, Janette; Gresham, Garold

    2014-07-01

    Pelletization process variables, including grind size (4, 6mm), die speed (40, 50, 60 Hz), and preheating (none, 70°C), were evaluated to understand their effect on pellet quality attributes and sugar yields of ammonia fiber expansion (AFEX) pretreated biomass. The bulk density of the pelletized AFEX corn stover was three to six times greater compared to untreated and AFEX-treated corn stover. Also, the durability of the pelletized AFEX corn stover was>97.5% for all pelletization conditions studied except for preheated pellets. Die speed had no effect on enzymatic hydrolysis sugar yields of pellets. Pellets produced with preheating or a larger grind size (6mm) had similar or lower sugar yields. Pellets generated with 4mm AFEX-treated corn stover, a 60Hz die speed, and no preheating resulted in pellets with similar or greater density, durability, and sugar yields compared to other pelletization conditions.

  12. Differences between pellets from biomass made in manufactory and in domestic conditions

    NASA Astrophysics Data System (ADS)

    Holubcik, Michal; Jachniak, Ewa; Smatanová, Helena

    2014-08-01

    Pellets from biomass are more and more used. As input material can be used various types of biomass, like wood, straw, grass or different organic materials. A lot of people want to produce pellets from biomass in domestic condition. But qualities of these pellets don't achieve quality of pellets made in manufacture. In this work are compared energetic and qualitative parameters of pellets made from spruce wood and wheat straw in domestic condition and in manufacture. There are results from moisture content, total heating value, mechanical durability, amount of fines and disintegration time in water test.

  13. Design considerations for single-stage and two-stage pneumatic pellet injectors

    SciTech Connect

    Gouge, M.J.; Combs, S.K.; Fisher, P.W.; Milora, S.L.

    1988-09-01

    Performance of single-stage pneumatic pellet injectors is compared with several models for one-dimensional, compressible fluid flow. Agreement is quite good for models that reflect actual breech chamber geometry and incorporate nonideal effects such as gas friction. Several methods of improving the performance of single-stage pneumatic pellet injectors in the near term are outlined. The design and performance of two-stage pneumatic pellet injectors are discussed, and initial data from the two-stage pneumatic pellet injector test facility at Oak Ridge National Laboratory are presented. Finally, a concept for a repeating two-stage pneumatic pellet injector is described. 27 refs., 8 figs., 3 tabs.

  14. Burn-rate studies with iron/potassium perchlorate heat pellets

    SciTech Connect

    Reed, J.W.; Walters, R.R. ); Guidotti, R.A.; Jacobson, A.K. )

    1991-01-01

    A detailed study was conducted on factors which could possibly influence the burn rate of Fe/KC10{sub 4} heat pellets. The burning process was monitored with a high-speed (1000 frames per second) video analysis system. The substrate and pellet thickness had little effect upon the burn rate of heat pellets. The pellet density, composition, and Fe particle size, however, affected the burn rates significantly. By proper adjustment of these parameters, the burn rate of heat pellets can be affected. This, in turn, can be used to influence the rise times of thermal batteries that use this type of pyrotechnic heat source.

  15. Burn-rate studies with iron/potassium perchlorate heat pellets

    SciTech Connect

    Reed, J.W.; Walters, R.R.; Guidotti, R.A.; Jacobson, A.K.

    1991-12-31

    A detailed study was conducted on factors which could possibly influence the burn rate of Fe/KC10{sub 4} heat pellets. The burning process was monitored with a high-speed (1000 frames per second) video analysis system. The substrate and pellet thickness had little effect upon the burn rate of heat pellets. The pellet density, composition, and Fe particle size, however, affected the burn rates significantly. By proper adjustment of these parameters, the burn rate of heat pellets can be affected. This, in turn, can be used to influence the rise times of thermal batteries that use this type of pyrotechnic heat source.

  16. Thermophilic Fungi: Their Physiology and Enzymes†

    PubMed Central

    Maheshwari, Ramesh; Bharadwaj, Girish; Bhat, Mahalingeshwara K.

    2000-01-01

    Thermophilic fungi are a small assemblage in mycota that have a minimum temperature of growth at or above 20°C and a maximum temperature of growth extending up to 60 to 62°C. As the only representatives of eukaryotic organisms that can grow at temperatures above 45°C, the thermophilic fungi are valuable experimental systems for investigations of mechanisms that allow growth at moderately high temperature yet limit their growth beyond 60 to 62°C. Although widespread in terrestrial habitats, they have remained underexplored compared to thermophilic species of eubacteria and archaea. However, thermophilic fungi are potential sources of enzymes with scientific and commercial interests. This review, for the first time, compiles information on the physiology and enzymes of thermophilic fungi. Thermophilic fungi can be grown in minimal media with metabolic rates and growth yields comparable to those of mesophilic fungi. Studies of their growth kinetics, respiration, mixed-substrate utilization, nutrient uptake, and protein breakdown rate have provided some basic information not only on thermophilic fungi but also on filamentous fungi in general. Some species have the ability to grow at ambient temperatures if cultures are initiated with germinated spores or mycelial inoculum or if a nutritionally rich medium is used. Thermophilic fungi have a powerful ability to degrade polysaccharide constituents of biomass. The properties of their enzymes show differences not only among species but also among strains of the same species. Their extracellular enzymes display temperature optima for activity that are close to or above the optimum temperature for the growth of organism and, in general, are more heat stable than those of the mesophilic fungi. Some extracellular enzymes from thermophilic fungi are being produced commercially, and a few others have commercial prospects. Genes of thermophilic fungi encoding lipase, protease, xylanase, and cellulase have been cloned and

  17. Striga Biocontrol on a Toothpick: A Readily Deployable and Inexpensive Method for Smallholder Farmers.

    PubMed

    Nzioki, Henry S; Oyosi, Florence; Morris, Cindy E; Kaya, Eylul; Pilgeram, Alice L; Baker, Claire S; Sands, David C

    2016-01-01

    Striga hermonthica (witchweed) is a parasitic weed that attacks and significantly reduces the yields of maize, sorghum, millet, and sugarcane throughout sub-Saharan Africa. Low cost management methods such as hand weeding, short crop rotations, trap cropping, or conventional biocontrol have not been effective. Likewise, Striga-tolerant or herbicide-resistant maize cultivars are higher yielding, but are often beyond the economic means of sustenance farmers. The fungal pathogen, Fusarium oxysporum f.sp. strigae, has been the object of numerous studies to develop Striga biocontrol. Under experimental conditions this pathogen can reduce the incidence of Striga infestation but field use is not extensive, perhaps because it has not been sufficiently effective in restoring crop yield and reducing the soil Striga seed bank. Here we brought together Kenyan and US crop scientists with smallholder farmers to develop and validate an effective biocontrol strategy for management of Striga on smallholder farms. Key components of this research project were the following: (1) Development of a two-step method of fungal delivery, including laboratory coating of primary inoculum on toothpicks, followed by on-farm production of secondary field inoculum in boiled rice enabling delivery of vigorous, fresh inoculum directly to the seedbed; (2) Training of smallholder farmers (85% women), to produce the biocontrol agent and incorporate it into their maize plantings in Striga-infested soils and collect agronomic data. The field tests expanded from 30 smallholder farmers to a two-season, 500-farmer plot trial including paired plus and minus biocontrol plots with fertilizer and hybrid seed in both plots and; (3) Concerted selection of variants of the pathogen identified for enhanced virulence, as has been demonstrated in other host parasite systems were employed here on Striga via pathogen excretion of the amino acids L-leucine and L-tyrosine that are toxic to Striga but innocuous to maize

  18. Striga Biocontrol on a Toothpick: A Readily Deployable and Inexpensive Method for Smallholder Farmers

    PubMed Central

    Nzioki, Henry S.; Oyosi, Florence; Morris, Cindy E.; Kaya, Eylul; Pilgeram, Alice L.; Baker, Claire S.; Sands, David C.

    2016-01-01

    Striga hermonthica (witchweed) is a parasitic weed that attacks and significantly reduces the yields of maize, sorghum, millet, and sugarcane throughout sub-Saharan Africa. Low cost management methods such as hand weeding, short crop rotations, trap cropping, or conventional biocontrol have not been effective. Likewise, Striga-tolerant or herbicide-resistant maize cultivars are higher yielding, but are often beyond the economic means of sustenance farmers. The fungal pathogen, Fusarium oxysporum f.sp. strigae, has been the object of numerous studies to develop Striga biocontrol. Under experimental conditions this pathogen can reduce the incidence of Striga infestation but field use is not extensive, perhaps because it has not been sufficiently effective in restoring crop yield and reducing the soil Striga seed bank. Here we brought together Kenyan and US crop scientists with smallholder farmers to develop and validate an effective biocontrol strategy for management of Striga on smallholder farms. Key components of this research project were the following: (1) Development of a two-step method of fungal delivery, including laboratory coating of primary inoculum on toothpicks, followed by on-farm production of secondary field inoculum in boiled rice enabling delivery of vigorous, fresh inoculum directly to the seedbed; (2) Training of smallholder farmers (85% women), to produce the biocontrol agent and incorporate it into their maize plantings in Striga-infested soils and collect agronomic data. The field tests expanded from 30 smallholder farmers to a two-season, 500-farmer plot trial including paired plus and minus biocontrol plots with fertilizer and hybrid seed in both plots and; (3) Concerted selection of variants of the pathogen identified for enhanced virulence, as has been demonstrated in other host parasite systems were employed here on Striga via pathogen excretion of the amino acids L-leucine and L-tyrosine that are toxic to Striga but innocuous to maize

  19. Dry Bag Isostatic Pressing for Improved Green Strength of Nuclear Fuel Pellets

    SciTech Connect

    G. W. Egeland; L. D. Zuck; W. R. Cannon; P. A. Lessing; P. G. Medvedev

    2010-11-01

    Dry bag isostatic pressing is proposed for mass production of nuclear fuel pellets. Dry bag isostatically pressed rods of a fuel surrogate (95% CeO2-5% HfO2) 200 mm long by 8 mm diameter were cut into pellets using a wire saw. Four different binder and two different CeO2 powder sources were investigated. The strength of the isostatically pressed pellets for all binder systems measured by diametral compression was about 50% higher than pellets produced by uniaxial dry pressing at the same pressure. It was proposed that the less uniform density of uniaxially pressed pellets accounted for the lower strength. The strength of pellets containing CeO2 powder with significantly higher moisture content was five times higher than pellets containing CeO2 powder with a low moisture content. Capillary pressure of the moisture was thought to supply the added binding strength.

  20. Porous desulfurization sorbent pellets containing a reactive metal oxide and an inert zirconium compound

    SciTech Connect

    Gardner, Todd H.; Gasper-Galvin, Lee D.

    1996-12-01

    Sorbent pellets for removing hydrogen sulfide from coal gas are prepared by combining a reactive oxide, in particular zinc oxide, with a zirconium compound such as an oxide, silicate, or aluminate of zirconium, and an inorganic binder and pelletizing and calcining the mixture. Alternately, the zinc oxide may be replaced by copper oxide or a combination of copper, molybdenum, and manganese oxides. The pellet components may be mixed in dry form, moistened to produce a paste, and converted to pellets by forming an aqueous slurry of the components and spray drying the slurry, or the reactive oxide may be formed on existing zirconium-containing catalyst-carrier pellets by infusing a solution of a salt of the active metal onto the existing pellets and firing at a high temperature to produce the oxide. Pellets made according to this invention show a high reactivity with hydrogen sulfide and durability such as to be useful over repeated cycles of sorption and regeneration.