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Sample records for duddingtonia flagrans chlamydospores

  1. Digestibility of Duddingtonia flagrans chlamydospores in ruminants: in vitro and in vivo studies

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    Mendoza-de-Gives Pedro

    2009-12-01

    Full Text Available Abstract Background The use of Duddingtonia flagrans as a tool for the biological control of gastrointestinal nematodes (GIN is a promising alternative to anthelmintics. The chlamydospores of D. flagrans are orally dosed and their thick cell wall gives them the capacity to resist digestion and pass through the gastrointestinal tract (GIT. Chlamydospores reaching the faeces are able to germinate and trap nematode larvae. The efficacy of this control method is based on reducing the numbers of infective larvae leaving the faeces. Techniques have recently been developed for quantifying the numbers of chlamydospores in faeces. As the number of non-digested spores could be relevant in the design and optimization of dosing programmes for the control of GIN infective larvae, the aim of the present study was to estimate the loss of D. flagrans chlamydospores during their passage through the ruminant gastrointestinal tract using in vitro and in vivo techniques. Results After in vitro rumen digestion, chlamydospore recovery was not different from the quantity originally incubated (undigested spores (P > 0.05. In vitro rumen+abomasum digestion caused nearly 36% loss of the chlamydospores originally incubated (P In vivo apparent chlamydospore digestibility in sheep showed a loss of 89.7% of the chlamydospores (P Conclusions The loss of chlamydospores was evident under in vitro and in vivo conditions. Negligible amounts of spores were lost during the in vitro rumen digestion. However, in vitro rumen+abomasum digestion resulted in a chlamydospore loss of approximately 36%. In vivo passage through the sheep GIT resulted in a total loss of 89.7% of the orally administered spores.

  2. Induction of traps by Ostertagia ostertagi larvae, chlamydospore production and growth rate in the nematode-trapping fungus Duddingtonia flagrans

    DEFF Research Database (Denmark)

    Grønvold, J.; Nansen, P.; Henriksen, S. A.;

    1996-01-01

    Biological control of parasitic nematodes of domestic animals can be achieved by feeding host animals chlamydospores of the nematode-trapping fungus Duddingtonia flagrans. In the host faeces, D. flagrans develop traps that may catch nematode larvae. In experiments on agar, D. flagrans had a growth...... rate between 15 and 60 mm/week at temperatures between 20 and 30 degrees C. The presence of nematodes induces the fungus to produce traps. The rate of trap formation in D. flagrans has an optimum at 30 degrees C, producing 700-800 traps/cm(2)/2 days, when induced by 20 nematodes/cm(2) on agar....... Approaching 10 and 35 degrees C the ability to produce traps is gradually reduced. The response of chlamydospore production on agar to changes in temperature is the same as that for trap formation. On agar, at 10, 20 and 30 degrees C D. flagrans loses its trap inducibility after 2-3 weeks. During the ageing...

  3. Duddingtonia flagrans chlamydospores in nutritional pellets: effect of storage time and conditions on the trapping ability against Haemonchus contortus larvae.

    Science.gov (United States)

    Fitz-Aranda, J A; Mendoza-de-Gives, P; Torres-Acosta, J F J; Liébano-Hernández, E; López-Arellano, M E; Sandoval-Castro, C A; Quiroz-Romero, H

    2015-01-01

    The study evaluated the effect of storage time and conditions of nutritional pellets (NP) containing Duddingtonia flagrans chlamydospores on its in vitro trapping ability against Haemonchus contortus L3 larvae. The treated batch (200 NP) contained 4 × 106 chlamydospores of the FTH0-8 strain, whereas the control batch (200 NP) was produced without spores. Both NP batches were exposed to four experimental storage conditions: (T1) shelves (indoors); (T2) refrigeration (4°C); (T3) outdoors under a roof; and (T4) 100% outdoors. Each group comprised 48 NP with spores and 48 NP without spores (control). The ability of D. flagrans spores to trap H. contortus L3 larvae was evaluated for 8 weeks for each storage condition. For that purpose, six randomly selected NP with spores were compared to their respective control NP. Each NP was individually crushed. The crushed material (1 g) was placed on the surface of a 2% water agar plate with 200 H. contortus L3 larvae. Plates were sealed and were incubated at room temperature for 8 days. The whole content of every plate was transferred to a Baermann apparatus to recover the remaining larvae. There was a clear larval reduction in the NP with spores, compared to the respective control NP in the four storage conditions (P< 0.05). The mean reductions ( ± SEM) of the storage conditions were 67 ± 4.9 (T2), 77 ± 6.1 (T1), 81.5 ± 3.8 (T4) and 82.1 ± 2.5 (T3). Larval reductions were similar at all times and were not affected by storage conditions or storage time (R 20.05). The long-term shelf-life of the chlamydospores in the NP suggests that this spore dosage technology is a viable option.

  4. Efficiency of feeding Duddingtonia flagrans chlamydospores to control nematode parasites of first-season grazing goats in France.

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    Paraud, C; Pors, I; Chartier, C

    2007-04-01

    A field trial, conducted over two consecutive years, was aimed at assessing the efficacy of the administration of spores of the nematophagous fungus Duddingtonia flagrans to young goats for the control of nematode parasite infections on a French commercial dairy goat flock. For both years, the first-year grazing kids were divided into two similarly managed groups (fungus and control groups): in 2003 a daily dose rate of 5 x 10(5) spores/kg body weight was given to the fungus-group animals, while in 2004 a daily dose rate of 10(6) spores/kg body weight was used; the other half of the kids, acting as control, did not receive the spores. Parameters measured every 3 weeks included nematode egg excretion, larval development in faecal cultures and pasture larval counts. Additionally, at the beginning, the middle and the end of each grazing season, the goats were weighed and blood samples for pepsinogen determination were collected. In 2003, similar results were recorded for all the measured parameters in the control and fungus groups. In contrast, in 2004, the kids receiving the spores showed lower faecal egg counts and pepsinogen levels at the end of the season and higher growth rate compared to kids of the control group.

  5. Duddingtonia flagrans in the control of gastrointestinal nematodes of horses.

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    Buzatti, Andréia; de Paula Santos, Clóvis; Fernandes, Maria Angela Machado; Yoshitani, Ursula Yaeko; Sprenger, Lew Kan; dos Santos, Carolina Dallagassa; Molento, Marcelo Beltrão

    2015-12-01

    Horses can harbor a large amount of parasites that may cause serious clinical signs even death. The aim of this study was to evaluate the predatory activity of the fungus Duddingtonia flagrans against infective larvae (L3) of gastrointestinal nematodes of horses in fecal culture. The experimental design was completely randomized with three treated groups (G1, G2 and G3) and one control (CG), using eight animals/group. The treated animals received G1: 1.5 × 10(5); G2: 3 × 10(5) and G3: 6 × 10(5) chlamydospores of D. flagrans/kg body weight during 21 days. The fungi preparation was given at every other three-day interval. Faecal samples were collected during 30 days, on the same interval, to perform the fecal egg counts (EPG) and fecal culture for each horse. All groups demonstrated similar results for the EPG (P > 0.05) counts. D. flagrans significantly reduced (P biological control with the predacious fungi D. flagrans is still a promising free-living parasite regulator alternative to be use in livestock.

  6. Efficacy of Clonostachys rosea and Duddingtonia flagrans in Reducing the Haemonchus contortus Infective Larvae

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    Manoel Eduardo da Silva

    2015-01-01

    Full Text Available The biocontrol is proven effective in reducing in vitro and in situ free-living stages of major gastrointestinal helminths, allowing progress in reducing losses by parasitism, maximizing production, and productivity. This study aimed at evaluating the predatory activity of fungal isolates of Duddingtonia flagrans and Clonostachys rosea species and its association on infective larvae (L3 of H. contortus in microplots formed by grasses and maintained in a protected environment. All groups were added with 10 mL of an aqueous suspension with 618 H. contortus L3 approximately. Group 1 was used as control and only received the infective larvae. Groups 2 and 3 received D. flagrans chlamydospores and C. rosea conidia at doses of 5 × 106. Group 4 received the combination of 5 × 106 D. flagrans chlamydospores + 5 × 106 C. rosea conidia. D. flagrans and C. rosea showed nematicidal effectiveness reducing by 91.5 and 88.9%, respectively, the population of H. contortus L3. However, when used in combination efficiency decreased to 74.5% predation of H. contortus L3. These results demonstrate the need for further studies to determine the existence of additive effects, synergistic or antagonistic, between these species.

  7. Efficacy of Clonostachys rosea and Duddingtonia flagrans in Reducing the Haemonchus contortus Infective Larvae

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    da Silva, Manoel Eduardo; Braga, Fabio Ribeiro; de Gives, Pedro Mendoza; Uriostegui, Miguel Angel Mercado; Reyes, Manuela; Soares, Filippe Elias de Freitas; de Carvalho, Lorendane Millena; Rodrigues, Francielle Bosi; de Araújo, Jackson Victor

    2015-01-01

    The biocontrol is proven effective in reducing in vitro and in situ free-living stages of major gastrointestinal helminths, allowing progress in reducing losses by parasitism, maximizing production, and productivity. This study aimed at evaluating the predatory activity of fungal isolates of Duddingtonia flagrans and Clonostachys rosea species and its association on infective larvae (L3) of H. contortus in microplots formed by grasses and maintained in a protected environment. All groups were added with 10 mL of an aqueous suspension with 618 H. contortus L3 approximately. Group 1 was used as control and only received the infective larvae. Groups 2 and 3 received D. flagrans chlamydospores and C. rosea conidia at doses of 5 × 106. Group 4 received the combination of 5 × 106 D. flagrans chlamydospores + 5 × 106 C. rosea conidia. D. flagrans and C. rosea showed nematicidal effectiveness reducing by 91.5 and 88.9%, respectively, the population of H. contortus L3. However, when used in combination efficiency decreased to 74.5% predation of H. contortus L3. These results demonstrate the need for further studies to determine the existence of additive effects, synergistic or antagonistic, between these species. PMID:26504809

  8. Biological control of gastrointestinal parasitic nematodes using Duddingtonia flagrans in sheep under natural conditions in Mexico.

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    Mendoza-De Gives, Pedro; Zapata Nieto, Claudia; Hernández, Enrique Liébano; Arellano, María Eugenia López; Rodríguez, David Herrera; Garduño, Roberto González

    2006-10-01

    This investigation was aimed to evaluate the use of an oral bio-preparation containing Duddingtonia flagrans chlamydospores for the control of sheep gastrointestinal parasitic nematodes under the Mexican cold high plateau conditions. Two groups of gastrointestinal parasitic nematode naturally infected sheep, were randomly selected and located into two free-gastrointestinal nematode larvae paddocks. Group 1 received once a week a supplement containing D. flagrans chlamydospores mixed with oats and molasses. Group 2 received a similar supplement without any fungal material. After 5 months grazing animals were discarded from the experiment and two groups of free-nematode "tracer" sheep were located into the same paddocks to collect larvae from the contaminated pastures. Animals were slaughtered and necropsied and the nematodes were obtained and counted. A screening of the number of gastrointestinal nematode larvae present on the grass was performed and compared between the two grazing areas. The results showed 56% reduction in the Ostertagia (Teladorsagia) circumcincta and 94% reduction in the Nematodirus sp. population of the "tracer" sheep who grazed on the D. flagrans-treated sheep area, compared to the nematode population in animals grazed on the non-treated area. The results of the number of larvae on the grazing pastures showed a 51.1% reduction for H. contortus, and 100% for Cooperia sp. in the area with fungi. In the case of Trichostrongylus sp. no reduction was observed, when compared to the control group.

  9. Efficacy of an energy block containing Duddingtonia flagrans in the control of gastrointestinal nematodes of sheep.

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    Sagüés, María F; Fusé, Luis A; Fernández, Alicia S; Iglesias, Lucía E; Moreno, Fabiana C; Saumell, Carlos A

    2011-09-01

    The efficacy of the nematode-trapping fungus Duddingtonia flagrans incorporated into an energy block was evaluated for the control of gastrointestinal nematodes in sheep. Four naturally parasitised sheep with average nematode egg counts of 2,470 eggs per gram grazed by pairs on two similar parasite-free paddocks for 30 days. During that period, one pair of sheep (treated animals, T1) received an energy block containing chlamydospores of D. flagrans at a dose of 200,000 chlamydopores/kg bw/day, while the second pair (control animals, C1) received a fungus-free energy block. The animals in both groups were taken off the paddocks after contaminating the pastures for a month with either nematode eggs plus fungal chlamydospores (T1) or nematode eggs alone (C1). Twelve parasite-free sheep were divided into two groups of six animals each, the treated group (T2) was placed on the paddock previously contaminated with parasites and fungus, while the control group (C2) was placed on the parasite-only paddock. These two groups grazed on their respective paddocks during 30 days and were then housed for 15 days, after which period they were slaughtered in order to determine the parasite burden present in each animal. Results showed that animals in group T2 harboured significantly less nematodes than their counterpart in group C2. The efficacy of D. flagrans was 92% against the total parasite burden, 100% against Haemonchus contortus and Teladorsagia circumcincta, 89.9% against Trichostrongylus colubriformis, 87.5% against Cooperia onchopora, and 90% against Trichostrongylus axei. No efficacy was detected against Nematodirus spathiger, Trichuris ovis and T. skrjabini.

  10. Effect of Duddingtonia flagrans against Ostertagia ostertagi in cattle grazing at different stocking rates

    DEFF Research Database (Denmark)

    Fernández, A.S.; Larsen, M.; Henningsen, E.

    1999-01-01

    The efficacy of an isolate of the nematophagous fungus Duddingtonia flagrans against gastrointestinal nematodes of cattle was examined at 2 dose levels on 2 permanent pastures, with high and low stocking rates, respectively. Thirty calves, experimentally infected with Ostertagia ostertagi, were...

  11. Isolation and Characterization of China Isolates of Duddingtonia flagrans, a Candidate of the Nematophagous Fungi for Biocontrol of Animal Parasitic Nematodes.

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    Wang, Bo-Bo; Liu, Wei; Chen, Ming-Yue; Li, Xuan; Han, Yuan; Xu, Qiang; Sun, Long-Jie; Xie, De-Qiong; Cai, Kui-Zheng; Liu, Yi-Zhong; Liu, Jun-Lin; Yi, Lin-Xin; Wang, Hui; Zhao, Ming-Wang; Li, Xiao-Shan; Wu, Jia-Yan; Yang, Jing; Wang, Yue-Ying

    2015-08-01

    The nematophagous fungus Duddingtonia flagrans has been investigated as a biological agent for the control of gastrointestinal nematodes infecting domestic animals in other countries. However, D. flagrans has not been detected in China. In this study 1,135 samples were examined from 2012 to 2014; 4 D. flagrans isolates (SDH 035, SDH 091, SFH 089, SFG 170) were obtained from the feces of domestic animals and dung compost. The 4 isolates were then characterized morphologically. The SDH 035 strain was characterized by sequencing the ITS1-5.8S rDNA-ITS2 region. A BLAST search showed that the SDH 035 strain (GenBank KP257593) was 100% identical to Arthrobotrys flagrans (AF106520) and was identified as D. flagrans. The morphological plasticity of the isolated strain and the interaction of this strain with the nematode targets were observed by subjecting the infected trichostrongylide L3 to scanning electron microscopy. At 6 and 8 hr after trichostrongylide L(3) was added, hyphal ramifications were observed and L(3) were captured, respectively. Scanning electron micrographs were obtained at 0, 6, 12, 18, 24, 30, 36, 42, and 48 hr, where 0 is the time when trichostrongylide L(3) were first captured by the fungus. The details of the capture process by the fungus are also described. Chlamydospores were observed in the body of L(3) in the late stage of digestion. A sticky substance and bacteria could be observed in contact areas between predation structures and nematode cuticle.

  12. Pemakaian Duddingtonia flagrans dan Saccharomyces cerevisiae dalam Mereduksi Larva Infektif Haemonchus contortus (THE STUDY OF DUDDINGTONIA FLAGRANS AND SACCHAROMYCES CEREVISIAE USE ON REDUCING OF INFECTIVE HAEMONCHUS CONTORTUS LARVAE

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    Riza Zainuddin Ahmad

    2014-04-01

    Full Text Available The use of Duddingtonia flagrans as the biological control of nomatode infections has been widelyreported. However, no report is available on the use of yeast Saccharomyces cerviciacae for such purpose.The aim of this study was to ivestigate the use of both fungi to reduce the number of Heamoncus contortusinfective larvae. Agar and fecal media containing the spore of the fungi was inoculated with infected H.contortus larvae (3rd stage. Fecal media containing the fungi was prepared by oral inoculation of sheepwith liquid containing 106, 107 spores of D. flagrans, and 106, 107 spores of D. flagrans, and 106, 1012 sporesof S. cerviciae. The number of larvae trapped in the fungi was counted. The result showed both fungi wereable to reduce the number of infective lave. However, for D. flagrans, beside it able to kill the larvae, it alsoable to trap the larva which did not occur in S. cerviceae. The combination of both fungi can be used to reduceof the number of invected H. contortus larvae.

  13. Duddingtonia flagrans: controle biológico de nematodeos de bovinos a campo Duddingtonia flagrans: biological control of cattle nematodes in the field

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    Marta Bañolas Jobim

    2008-11-01

    Full Text Available O controle biológico é um método para diminuir uma população pela utilização de antagonista natural. No presente estudo, testou-se a eficácia do fungo nematófago Duddingtonia flagrans no controle de nematódeos parasitos gastrintestinais de bovinos criados à campo no município de Júlio de Castilhos. Foram utilizados 20 bezerros, distribuídos igualmente em duas áreas formadas por pastagem nativa. O grupo A foi tratado com o fungo D. flagrans, cultivado em sorgo, numa concentração de 1x10(6clamidósporos kg-1 de peso animal, misturados em ração de manutenção, diariamente, durante oito meses. O grupo B serviu como controle e não recebeu fungo, apenas ração. Foram coletadas amostras para contagem de ovos por grama de fezes (OPG semanalmente. Mensalmente, foram realizadas coproculturas para identificar as espécies de larvas de nematódeos, a pesagem dos animais e a coleta de pasto para contagem das larvas na pastagem. Dados de temperatura e índice pluviométrico foram registrados diariamente. O OPG foi reduzido no grupo tratado, em média 56,8,% nos últimos três meses de experimento, variando entre 40,4 e 67,1% no grupo tratado (PBiological control is an alternative method to reduce parasite's population by the use of natural antagonist. In the present study, efficacy of nematophagous fungus Duddingtonia flagrans was tested to control gastrointestinal nematodes parasites of cattle livestock in the field. Twenty calves were used, distributed equally in two distinct plots formed by native pasture. Group A was treated with D. flagrans fungus, cultivated in sorghum (1x10(6 clamidospores kg-1 body weight mixed with maintenance ration, each day, during eight months. Group B served as a control and did not receive the fungus. Samples for faecal egg count (FEC, were collected each week. There were monthly counts in faecal cultures to identify the species of nematodes larvae, animals weight, blood collection to determine red cell

  14. The efficacy of two isolates of the nematode-trapping fungus Duddingtonia flagrans against Dictyocaulus viviparus larvae in faeces

    DEFF Research Database (Denmark)

    Fernandez, A.S.; Larsen, M.; Nansen, P.

    1999-01-01

    A series of experiments was carried out to examine the effects of two different isolates of the nematode-trapping fungus Duddingtonia flagrans to reduce the number of free-living larvae of the bovine lungworm, Dictyocaulus viviparus. A laboratory dose-titration assay showed that isolates CI3 and ...

  15. Lack of negative effects of the biological control agent Duddingtonia flagrans on soil nematodes and other nematophagous fungi.

    Science.gov (United States)

    Saumell, C A; Fernández, A S; Echevarria, F; Gonçalves, I; Iglesias, L; Sagües, M F; Rodríguez, E M

    2016-11-01

    The possible environmental effects of the massive use of Duddingtonia flagrans for controlling sheep nematodes were evaluated in two regions. Non-supplemented faeces and faeces from sheep supplemented with D. flagrans were deposited three times on pasture plots and samples were collected 7 and 14 days post-deposition. Samples were cultured in agar-water (2%) with Panagrellus spp. to recover D. flagrans and other nematophagous fungi, and soil nematodes were extracted using Baermann funnels and counted. No significant differences in the populations of soil nematodes and fungi colonizing sheep faeces (P > 0.05) were observed between supplemented and non-supplemented groups, except in one sample. The topsoil in contact with the faeces was sampled 1-4 months post-deposition, revealing that, with one exception, D. flagrans did not persist in soil beyond 2 months post-deposition. Duddingtonia flagrans does not affect faecal colonization by other fungi and soil nematodes and, once deployed on pasture, does not survive for long periods in the environment.

  16. Biological control of infective larvae of a gastro-intestinal nematode (Teladorsagia circumcincta) and a small lungworm (Muellerius capillaris) by Duddingtonia flagrans in goat faeces.

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    Paraud, C; Chartier, C

    2003-01-01

    The high prevalence of benzimidazole-resistant nematodes in French grazing dairy goat flocks led to a search for nematode-control schemes based on integrated approaches with non-chemical options, like vaccination, grazing management, or biological control using nematophagous fungi. The effect of the daily feeding of goats with spores of the nematophagous fungus Duddingtonia flagrans on third-stage larvae (L3) of Teladorsagia circumcincta was examined in faecal cultures. In addition, the effect of D. flagrans on the survival of first-stage larvae (L1) of Muellerius capillaris was tested. Twenty-two culled dairy goats previously raised in a zero-grazing system were twice infected at monthly intervals with 5,000 and then 7,500 T. circumcincta L3. Eight animals were infected with a benzimidazole-susceptible (BZs) strain while the remainder received a benzimidazole-resistant one (BZr). Six culled goats naturally infected with M. capillaris were purchased from private farms. All the goats were divided in two groups, one group receiving daily 5 x 10(5) chlamydospores of D. flagrans/kg body weight per goat for seven consecutive days in the food, the other group acting as control. For T. circumcincta-infected goats, individual egg counts and coprocultures (13 days, 25 degrees C) followed by L3 extraction with the Baermann method were performed. For M. capillaris-infected goats, extraction of L1 with the Baermann apparatus was individually performed on day 0 and after coprocultures on days 7, 10 and 14. Reductions in percentage development of T. circumcincta L3 in fungus groups compared with control groups ranged from 84% (BZs strain) to 90% (BZr strain). A decrease in M. capillaris L1 recovery was noted on days 7 and 10 (a reduction of 70% compared with day 0) and on day 14 (85%), but this pattern was similar in both groups, whether receiving the fungus or not. At the dosage of 5 x 10(5) spores/kg body weight, D. flagrans was highly effective in reducing the larval

  17. Biological control of sheep parasites using Duddingtonia flagrans: trials on commercial farms in Sweden.

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    Waller, P J; Ljungström, B L; Schwan, O; Martin, L Rudby; Morrison, D A; Rydzik, A

    2006-01-01

    Trials were conducted on 3 commercial sheep farms in Sweden to assess the effect of administering spores of the nematode trapping fungus, Duddingtonia flagrans, together with supplementary feed to lactating ewes for the first 6 weeks from turn-out on pastures in spring. Also control groups of ewes, receiving only feed supplement, were established on all 3 farms. Groups were monitored by intensive parasitological investigation. The ewes and their lambs were moved in late June to saved pastures for summer grazing, the lambs receiving an anthelmintic treatment at this time. After approximately 6 weeks on summer pasture the lambs were weaned, treated a second time with anthelmintic, and returned to their original lambing pastures for finishing. Decisions as to when lambs were to be marketed were entirely at the discretion of the farmer co-operators. No difference in lamb performance was found between the two treatments on all three farms. This was attributed to the high levels of nutrition initially of the ewes limiting their post-partum rise in nematode faecal egg counts in spring, which in turn resulted in low levels of nematode infection on pastures throughout the autumn period. Additionally, pastures were of good quality for the lambs during the finishing period, so they grew at optimal rates as far as the farmers were concerned.

  18. Effect of the nematode-trapping fungus Duddingtonia flagrans on the free-living stages of horse parasitic nematodes: a plot study

    DEFF Research Database (Denmark)

    Fernandez, A.S.; Larsen, M.; Nansen, P.

    1997-01-01

    A plot experiment was conducted to investigate the ability of the nematode-trapping fungus Duddingtonia flagrans to reduce the transmission of infective horse strongyle larvae from deposited dung onto surrounding herbage. At three different times during the summer 1995, three groups of horses...

  19. The ability of the nematode-trapping fungus Duddingtonia flagrans to reduce the transmission of infective Ostertagia ostertagi larvae from faeces to herbage

    DEFF Research Database (Denmark)

    Fernandez, A.S.; Larsen, M.; Nansen, P.

    1999-01-01

    The ability of two isolates of the nematode-trapping fungus Duddingtonia flagrans to reduce the numbers of gastrointestinal nematode larvae on herbage was tested in three plot studies. Artificially prepared cow pats containing Ostertagia ostertagi eggs, with and without fungal spores, were...

  20. The effect of the nematode-destroying fungus Duddingtonia flagrans against Oesophagostomum dentatum larvae in faeces from pigs fed different diets

    DEFF Research Database (Denmark)

    Petkevicius, S.; Larsen, M.; Knudsen, K.E.B.;

    1998-01-01

    This study examined the effects of the nematode-destroying fungus Duddingtonia flagrans on the development of Oesophagostomum dentatum infective, third stage (L-3) larvae in faecal cultures from pigs fed five and four different diets with different levels of undigested dietary fibre residues...... and dry matter. The results demonstrated that different isolates of the nematode-destroying fungus D. flagrans were equally able to significantly reduce the number of O. dentatum infective larvae in vitro. The recovery of larvae was apparently higher in faecal cultures established on faeces from pigs fed...

  1. Biological control of horse cyathostomin (Nematoda: Cyathostominae) using the nematophagous fungus Duddingtonia flagrans in tropical southeastern Brazil.

    Science.gov (United States)

    Braga, Fabio Ribeiro; Araújo, Jackson Victor; Silva, André Ricardo; Araujo, Juliana Milani; Carvalho, Rogério Oliva; Tavela, Alexandre Oliveira; Campos, Artur Kanadani; Carvalho, Giovanni Ribeiro

    2009-08-26

    The viability of a fungal formulation using the nematode-trapping fungus Duddingtonia flagrans was assessed for the biological control of horse cyathostomin. Two groups (fungus-treated and control without fungus treatment), consisting of eight crossbred mares (3-18 years of age) were fed on Cynodon sp. pasture naturally infected with equine cyathostome larvae. Each animal of the treated group received oral doses of sodium alginate mycelial pellets (1g/(10 kg live weight week)), during 6 months. Significant reduction (pcontrol group. There was difference (pcontrol group, during the experimental period (May-October). Difference of 82.5% (pcontrol group in the sampling distance (20-40 cm) from fecal pats. During the last 3 months of the experimental period (August, September and October), fungus-treated mares had significant weight gain (pcontrol group, an increment of 38 kg. The treatment with sodium alginate pellets containing the nematode-trapping fungus D. flagrans reduced cyathostomin in tropical southeastern Brazil and could be an effective tool for biological control of this parasitic nematode in horses.

  2. Biological control of trichostrongyles in beef cattle by the nematophagous fungus Duddingtonia flagrans in tropical southeastern Brazil.

    Science.gov (United States)

    Assis, R C L; Luns, F D; Araújo, J V; Braga, F R

    2012-11-01

    The efficacy of a fungal formulation based on the nematophagous fungus Duddingtonia flagrans was assessed in the control of cattle trichostrongyles. Twenty male Nellore calves, six-month-old, divided in two groups (fungus-treated and control without fungus) were fed on a pasture of Brachiaria decumbens naturally infected with larvae of bovine trichostrongyles. Animals of the treated group received doses of sodium alginate mycelial pellets orally (1 g/10 kg live weight, twice a week), for 12 months. Feces samples were collected for egg count (eggs per gram of feces-EPG) and coprocultures during 12 months. There was a significant reduction in EPG (56.7%) and infective larvae (L3) in coprocultures (60.5%) for animals of the treated group in relation to the control group at the end of the study. There was a significant reduction of L3 (64.5%) in herbage samples collected up to 0-20 cm from fecal pats and 73.2% in distant samples (20-40 cm) between the fungus-treated group and the control group. The treatment with sodium alginate pellets containing the nematode trapping fungus D. flagrans reduced trichostrongylid in tropical southeastern Brazil and could be an effective tool for biological control of this parasitic nematode in beef cattle.

  3. Kinetics of capture and infection of infective larvae of trichostrongylides and free-living nematodes Panagrellus sp. by Duddingtonia flagrans.

    Science.gov (United States)

    da Cruz, Daniela Guedes; Araújo, Flávia Biasoli; Molento, Marcelo Beltrão; Damatta, Renato Augusto; de Paula Santos, Clóvis

    2011-10-01

    Duddingtonia flagrans, a nematode-trapping fungus, has been investigated as an agent for biological control against infective larvae of gastrointestinal nematode parasites of production animals. The initial process of nematode-trapping fungi infection is based on an interaction between the trap structure of the fungus and the surface of the nematode cuticle. This report investigates by light and scanning electron microscopy the kinetics of capture and infection during the interaction of D. flagrans with the infective larvae (L(3)) of trichostrongylides and the free-living nematode Panagrellus sp. D. flagrans was cultivated for 7 days in a Petri dish containing agar-water. L(3) and Panagrellus sp. were inoculated in the Petri dishes and the samples consisting of agar-L(3)-fungi and agar-Panagrellus sp.-fungi were collected after 10, 20, 30, 40, 50, 60, and 70 min and 3, 4, 5, 10, 15, 20, and 25 h of interaction. All samples were observed by light microscopy. The samples with 1, 5, 15, and 25 h of interaction were also analyzed by scanning electron microscopy. The interaction was monitored up to 25 h. An initial differentiation of predation structures was observed after 30 min of interaction. The presence of traps and of captured L(3) or Panagrellus sp. occurred after 70 min. The live captured nematodes were observed up to 3 h of interaction. However, after 4 h, all Panagrellus sp. were dead. It took 15 h of interaction for the fungus to invade the L(3), and the presence of hyphae inside the nematode near the region of penetration was evident. At this time, the hyphae had filled the whole body of Panagrellus sp. The complete occupation of the body of L(3) occurred at 20 h of interaction and with 25 h the nematode was completely damaged except for the cuticle. Although the double cuticle of L(3) slows the penetration of D. flagrans, it was possible to verify that the process of trap formation and capture occurs quickly when both nematodes were tested, suggesting that

  4. IN VITRO CONTROL OF INFECTIVE CYATHOSTOMES LARVAE (NEMATODE: CYATHOSTOMINAE FROM EQUINES USING PREDACIOUS FUNGUS Duddingtonia flagrans, Monacrosporium thaumasium e Arthrobotrys robusta CONTROLE IN VITRO DE LARVAS INFECTANTES DE CIATOSTOMÍNEOS (NEMATODA: CYATHOSTOMINAE DE EQUINOS UTILIZANDO OS FUNGOS PREDADORES Duddingtonia flagrans, Monacrosporium thaumasium e Arthrobotrys robusta

    Directory of Open Access Journals (Sweden)

    André Ricardo Silva

    2009-09-01

    Full Text Available The predatory capacity of three isolates of the nematodes predacious fungi Duddingtonia flagrans (AC001, Monacrosporium thaumasium and Arthrobotrys robusta on infective larvae of cyathostomes was evaluated in laboratorial conditions in medium water-agar 2% (WA 2%. The isolates AC001, NF34 and I31 had presented significant reduction (p<0.01 de 97.5%, 72.5% e 85% respectively in the average of infective larvae of ciathostomes recovered of the medium WA2% in the end of five days. The results of this assay evidence that these isolates could be used in the biological control of ciathostomes of equines.

    KEY WORDS:  Arthrobotrys robusta, Cyathostominae, equine, Duddingtonia flagrans, Monacrosporium thaumasium, Nematophagous fungi.

    A capacidade predatória de três isolados de fungos predadores de nematoides Duddingtonia flagrans (AC001, Monacrosporium thaumasium (NF34 e Arthrobotrys robusta (I31 sobre larvas infectantes de ciatostomíneos foi avaliada em condições laboratoriais em ensaio experimental em meio ágar-água 2% (AA 2%. Os isolados AC001, NF34 e I31 apresentaram redução significativa (p<0,01 de 97,5%, 72,5% e 85%, respectivamente, na média de larvas infectantes de ciatostomíneos recuperadas do meio AA2% ao final de sete dias. Os resultados deste ensaio evidenciam que esses isolados poderão ser utilizados no controle biológico de ciatostomíneos de equinos.
     
    PALAVRAS-CHAVES: Arthrobotrys robusta, ciatostomíneos, equinos, Duddingtonia flagrans, fungos nematófagos, Monacrosporium thaumasium.

  5. In vitro ovicidal activity of the nematophagous fungi Duddingtonia flagrans, Monacrosporium thaumasium and Pochonia chlamydosporia on Trichuris vulpis eggs.

    Science.gov (United States)

    Silva, A R; Araújo, J V; Braga, F R; Alves, C D F; Frassy, L N

    2010-08-27

    The in vitro effect of four isolates of the nematophagous fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34a) and Pochonia chlamydosporia (VC1 and VC4) on the eggs of Trichuris vulpis was evaluated. One thousand eggs of T. vulpis were plated on Petri dishes with 2% water-agar with the fungal isolates grown and without fungus as control. After 7, 14 and 21 days 100 eggs were removed from each plate and classified according to the following parameters: type 1, lytic effect without morphological damage to eggshell; type 2, lytic effect with morphological alteration of embryo and eggshell; and type 3, lytic effect with morphological alteration of embryo and eggshell, besides hyphal penetration and internal egg colonization. P. chlamydosporia demonstrated ovicidal activity (p<0.05) on the eggs of T. vulpis in the studied intervals presenting type 3 effect of 29.5% (VC1) and 36.5% (VC4), 59.5% (VC1) and 2.5% (VC4), 94.8% (VC1) and 2.95% (VC4) at 7, 14 and 21 days, respectively. The other fungi showed no type 3 effect. P. chlamydosporia should be a potential biological control agent of T. vulpis eggs.

  6. Comparative analysis of destruction of the infective forms of Trichuris trichiura and Haemonchus contortus by nematophagous fungi Pochonia chlamydosporia; Duddingtonia flagrans and Monacrosporium thaumasium by scanning electron microscopy.

    Science.gov (United States)

    Silva, A R; Araújo, J V; Braga, F R; Benjamim, L A; Souza, D L; Carvalho, R O

    2011-01-10

    The present study aimed to demonstrate by scanning electron microscopy (SEM) the in vitro predatory activity of nematophagous fungi Pochonia chlamydosporia (VC1 and VC4 isolates) Duddingtonia flagrans (AC001 isolate) and Monacrosporium thaumasium (NF34a isolate) on eggs of Trichuristrichiura and infective larvae (L3) of Haemonchus contortus. The work was divided into two experimental tests (A and B). In tests A and B, the predatory activity of nematophagous fungi P. chlamydosporia, D. flagrans and M. thaumasium on eggs of T. trichiura and H. contortus L3 was observed. After 6h, in test A, isolates P. chlamydosporia (VC1 and VC4) had a role in destroying eggs of T.trichiura. For fungi D. flagrans and M. thaumasium the ovicidal activity on T. trichiura eggs was not observed. Test B showed that D. flagrans (AC001) and M. thaumasium (NF34a) were capable of predating H. contortus L3, but no predation by the fungus P. chlamydosporia was seen. These fungi can offer potential for the biological control of nematodes.

  7. Biotic and abiotic factors influencing growth rate and production of traps by the nematode-trapping fungus Duddingtonia flagrans when induced by Cooperia oncophora larvae

    DEFF Research Database (Denmark)

    Grønvold, J.; Wolstrup, J.; Nansen, P.

    1999-01-01

    A series of experiments on corn meal agar was carried out to evaluate the efficacy of the nematode-trapping fungus Duddingtonia flagrans in different abiotic and biotic conditions which occur in cow pats. Above a concentration of 50 parasitic larvae (L-3) cm(-2) the fungus produced a maximum...... of between 500 and 600 nets cm(-2) at 20 degrees C in 2 days on the surface of corn meal agar. There were no differences in the trap-producing capacity of three strains of D. flagrans (CIII4, CI3 and Trol A). On agar at 30 degrees and 20 degrees C, the fungus responded to Coaperia oncophora L-3 very quickly...... will be ready to attack parasitic larvae, when the oxygen tension increases as a result of, for example the activity of the coprophilic fauna. Artificial light giving 3000-3400 Lux on the surface of the agar significantly depressed the growth rate and the production of trapping nets in D, flagrans (CI3...

  8. Atividade predatória dos fungos nematófagos Duddingtonia flagrans, Monacrosporium thaumasium e Artrobotrys robusta sobre larvas infectantes de Strongyloides stercoralis Predatory activity of the nematophagous fungi Duddingtonia flagrans, Monacrosporium thaumasium and Arthrobotrys robusta on Strongyloides stercoralis infective larvae

    Directory of Open Access Journals (Sweden)

    Fabio Ribeiro Braga

    2010-10-01

    Full Text Available INTRODUÇÃO: Strongyloides stercoralis é um nematoide que infecta grande parte da população mundial. MÉTODOS: O objetivo deste trabalho foi comparar a capacidade predatória dos fungos nematófagos Duddingtonia flagrans (AC001, Monacrosporium thaumasium (NF34 e Arthrobotrys robusta (I-31 sobre larvas infectantes (L3 de Strongyloides stercoralis em condições laboratoriais no meio ágar-água 2%. RESULTADOS: Ao final do experimento, os percentuais de redução de L3 de Strongyloides stercoralis observados foram de: 83,7% (AC001; 75,5% (NF34 e 73,2% (I-31. CONCLUSÕES: Os fungos nematófagos foram capazes de capturar e destruir in vitro as L3, podendo ser utilizados como controladores biológicos de Strongyloides stercoralis.INTRODUCTION: Strongyloides stercoralis is a nematode that infects much of the population worldwide. METHODS: This study aimed to compare the ability of predatory nematophagous fungi Duddingtonia flagrans (AC001, Monacrosporium thaumasium (NF34 and Arthrobotrys robusta (I-31 on infective larvae (L3 of Strongyloides stercoralis in laboratory conditions on 2% water-agar. RESULTS: At the end of the experiment, the percentage reductions in Strongyloides stercoralis L3 were 83.7% (AC001, 75.5% (NF34 and 73.2% (I-31. CONCLUSIONS: The nematophagous fungi were able to capture and destroy the L3 in vitro and may be used as biological controls of Strongyloides stercoralis.

  9. In vitro evaluation of the effect of the nematophagous fungi Duddingtonia flagrans, Monacrosporium sinense, and Pochonia chlamydosporia on Ascaris suum eggs.

    Science.gov (United States)

    Araújo, J V; Braga, F R; Silva, A R; Araujo, J M; Tavela, A O

    2008-03-01

    The in vitro effect of four isolates of the nematophagous fungi Duddingtonia flagrans (AC 001), Monacrosporium sinense (SF 53), and Pochonia chlamydosporia (VC 1 and VC 4) on eggs of Ascaris suum was evaluated. One hundred thousand A. suum eggs were plated on 2% water-agar with the grown isolates and control without fungus. After 7, 14, and 21 days, 100 eggs were removed and classified according to the following parameters: type 1, lytic effect without morphological damage to eggshell; type 2, lytic effect with morphological alteration of embryo and eggshell; and type 3, lytic effect with morphological alteration of embryo and eggshell, besides hyphal penetration and internal egg colonization. P. chlamydosporia showed ovicidal activity (p suum eggs in the studied intervals of 13.3% (isolate VC 1) and 17.3% (isolate VC 4), 13.9% (VC 1) and 17.7% (VC 4), and 19% (VC 1) and 20% (VC4), respectively, at 7, 14, and 21 days. The other fungi showed no type 3 effect. P. chlamydosporia is a potential biological control agent of A. suum eggs.

  10. Effects of varied cultures and inductors on production of proteins and toxicity to nematodes or insects in the broth filtrate of Duddingtonia flagrans%不同培养基及诱导物对捕食性真菌Duddingtonia flagrans发酵液中蛋白质的产生及杀虫作用的影响

    Institute of Scientific and Technical Information of China (English)

    赵晓慧; 王瑞; 杨晓野; 杨莲茹; 苏佳; 李军燕; 李文生

    2012-01-01

    To study the production of proteins and toxicity to nematodes or insects in the broth filtrate of the nematode-trapping fungus,different liquid media with varied nutritional ingredients and inductors were used to culture Duddingtonia flagrans.The fermentation broth filtrations were collected,and the protein content,protease activity,alkaline phosphatase activity and toxicity of the broth filtration to nematodes or insects were evaluated to determine the best medium and induction agent for producing exoproteins and toxic substance to nematodes or insects.The results showed that different media and induction agents could significantly influence the metabolic process of D.flagrans,and it led to vary the types,concentration,activity of proteins and the phosphatase activity.Moreover,we also found the fermentation broth of D.flagrans not only had nematicidal activity,but also had a role to kill the fly larvae.The results above provided an important information for further studying the mechanism of nematode-trapping fungus to killing its prey.%为研究捕食性真菌Duddingtonia flagrans发酵液中蛋白质的产生及杀虫作用,使用不同营养成分组成的液体培养基及诱导物,对Duddingtonia flagrans进行培养和诱导,测定其发酵液中的蛋白质含量、蛋白酶活性、磷酸酶活性和杀虫作用,进而确定Duddingtonia flagrans产生胞外蛋白质和杀虫作用最适的培养基与诱导物。结果显示,不同培养基及诱导物对Duddingtonia flagrans的代谢过程会产生明显影响,导致其分泌的蛋白质种类、浓度以及蛋白酶和磷酸酶的活性显著不同;Duddingtonia flagrans发酵液不仅具有杀线虫活性,而且有杀蝇蛆作用。上述结果为进一步研究捕食线虫性真菌的杀虫机理提供了重要参考依据。

  11. Evaluation of the effectiveness of Duddingtonia flagrans and Monacrosporium thaumasium in the biological control of gastrointestinal nematodes in female bovines bred in the semiarid region.

    Science.gov (United States)

    Silva, Manoel Eduardo da; Braga, Fabio Ribeiro; Borges, Luana Alcântara; Oliveira, Jair Mendes de; Lima, Walter dos Santos; Guimarães, Marcos Pezzi; Araújo, Jackson Victor de

    2014-06-01

    Brazil has a herd of 212 million cattle and 171 million hectares of pastures that produce approximately 96 % of Brazilian beef. The Brazilian production system enables animal infection by endoparasites, which are considered one of the main obstacles for the development of this industry and are responsible for considerable economic losses. The control of parasitic diseases is performed via the administration of antiparasitic drugs, but they leave residues of the products in the treated animal, affect non-target organisms and select resistant strains of the parasites. The species D. flagrans and M. thaumasium are promising and sustainable alternatives for controlling gastrointestinal helminths of ruminants and other herbivores. In this study, we evaluated the efficacy of isolates of these species, formulated in a sodium alginate matrix and administered twice a week, to reduce the number of environmental infective larvae of gastrointestinal nematodes that affect prepubescent zebu females. The treated animals presented fewer eggs and a lower number of infective larvae per gram of faeces (p  0.05) among the treated and control groups. The use of sodium alginate pellets as vehicle for delivery of the fungus mycelia D. flagrans (isolate AC001) and M. thaumasium (isolate NF34A) proved effective in controlling trichostrongylids in prepubescent cows bred in the semi-arid region, with an effective reduction in the number of infective larvae in the pastures.

  12. Germination of Phytophthora ramorum chlamydospores: a comparison of separation method and chlamydospore age

    Science.gov (United States)

    Justin P. Shaffer; Jennifer L. Parke

    2013-01-01

    Phytophthora ramorum characteristically produces large amounts of chlamydospores in vitro, but the role of these propagules in the disease cycle remains unclear. Germination is difficult to observe and quantify if chlamydospores are not free of mycelium, and the low frequency of germination commonly reported suggests that...

  13. Effect of Duddingtonia flagrans against Ostertagia ostertagi in cattle grazing at different stocking rates

    DEFF Research Database (Denmark)

    Fernández, A.S.; Larsen, M.; Henningsen, E.

    1999-01-01

    divided into 3 comparable groups and allocated to 3 similar paddocks in each of the 2 trials. Two of the 3 groups received fungal material once per day during the initial 2 months, either at high dose (10(6) fungal spores/kg body weight) or low dose (5 x 10(5) or 2.5 x 10(5) fungal spores/kg body weight...

  14. The maturation and germination of Phytophthora ramorum Chlamydospores

    Science.gov (United States)

    Aaron L. Smith; Everett M. Hansen

    2008-01-01

    Chlamydospores are a distinctive feature of Phytophthora ramorum. They are formed quickly in agar, and within colonized leaves. We followed their development and maturation in vitro and in vivo, and studied conditions affecting their germination. Cell walls of mature P. ramorum chlamydospores...

  15. Chlamydospore Induction from Conidia of Cylindrocarpon destructans Isolated from Ginseng in Korea.

    Science.gov (United States)

    Kang, Yunhee; Kim, Mi Ran; Kim, Ki Hong; Lee, Jungkwan; Lee, Seung-Ho

    2016-03-01

    Cylindrocarpon destructans causes root rot disease in ginseng and can survive for a long time, producing chlamydospores. We optimized conditions to induce chlamydospore production from the conidia of C. destructans, isolated from Korean ginseng. This will provide the basis for testing the efficacy of control agents targeting these chlamydospores.

  16. Purification and germination of Candida albicans and Candida dubliniensis chlamydospores cultured in liquid media.

    LENUS (Irish Health Repository)

    Citiulo, Francesco

    2009-10-01

    Candida albicans and Candida dubliniensis are the only Candida sp. that have been observed to produce chlamydospores. The function of these large, thick-walled cells is currently unknown. In this report, we describe the production and purification of chlamydospores from these species in defined liquid media. Staining with the fluorescent dye FUN-1 indicated that chlamydospores are metabolically active cells, but that metabolic activity is undetectable in chlamydospores that are >30 days old. However, 5-15-day-old chlamydospores could be induced to produce daughter chlamydospores, blastospores, pseudohyphae and true hyphae depending on the incubation conditions used. Chlamydospores that were preinduced to germinate were also observed to escape from murine macrophages following phagocytosis, suggesting that these structures may be viable in vivo. Mycelium-attached and purified chlamydospores rapidly lost their viability in water and when subjected to dry stress, suggesting that they are unlikely to act as long-term storage structures. Instead, our data suggest that chlamydospores represent an alternative specialized form of growth by C. albicans and C. dubliniensis.

  17. Global Transcriptome Sequencing Identifies Chlamydospore Specific Markers in Candida albicans and Candida dubliniensis

    LENUS (Irish Health Repository)

    Palige, Katja

    2013-04-15

    Candida albicans and Candida dubliniensis are pathogenic fungi that are highly related but differ in virulence and in some phenotypic traits. During in vitro growth on certain nutrient-poor media, C. albicans and C. dubliniensis are the only yeast species which are able to produce chlamydospores, large thick-walled cells of unknown function. Interestingly, only C. dubliniensis forms pseudohyphae with abundant chlamydospores when grown on Staib medium, while C. albicans grows exclusively as a budding yeast. In order to further our understanding of chlamydospore development and assembly, we compared the global transcriptional profile of both species during growth in liquid Staib medium by RNA sequencing. We also included a C. albicans mutant in our study which lacks the morphogenetic transcriptional repressor Nrg1. This strain, which is characterized by its constitutive pseudohyphal growth, specifically produces masses of chlamydospores in Staib medium, similar to C. dubliniensis. This comparative approach identified a set of putatively chlamydospore-related genes. Two of the homologous C. albicans and C. dubliniensis genes (CSP1 and CSP2) which were most strongly upregulated during chlamydospore development were analysed in more detail. By use of the green fluorescent protein as a reporter, the encoded putative cell wall related proteins were found to exclusively localize to C. albicans and C. dubliniensis chlamydospores. Our findings uncover the first chlamydospore specific markers in Candida species and provide novel insights in the complex morphogenetic development of these important fungal pathogens.

  18. Simple identification of Trichophyton tonsurans by chlamydospore-like structures produced in culture media.

    Science.gov (United States)

    Mochizuki, Takashi; Anzawa, Kazushi; Sakata, Yuichi; Fujihiro, Machiko

    2013-12-01

    Trichophyton tonsurans is known to be the causative agent of a worldwide epidemic of dermatophytoses among contact sports practitioners, and is spreading among the general population of Japan. Prompt and simple identification of T. tonsurans in diagnostic laboratories is crucial to control infection. The present study evaluated the availability of observation of chlamydospore-like structures grown in culture media as a characteristic for identification of T. tonsurans. Twenty-five strains of T. tonsurans and five strains each of Trichophyton verrucosum, Trichophyton rubrum and Trichophyton mentagrophytes were inoculated on Mycosel agar plates and inoculated Petri dishes were observed by light microscopy from the reverse side. Twenty-three of 25 T. tonsurans strains showed chlamydospore-like structures within 5 days, and all strains at day 8. The numbers of chlamydospore-like structures were very abundant in most strains. The majority of strains of other species showed no chlamydospore-like structures, or very few when present. Positive for chlamydospore-like structures among 15 strains other than T. tonsurans was one strain at day 5 and six strains at day 8. As for the identification of T. tonsurans, presence of chlamydospore-like structures showed 92.0% sensitivity (23/25) and 93.3% specificity (14/15) at day 5, and 100% sensitivity (25/25) and 60.0% specificity (9/15) at day 8. Electron microscopic findings suggest chlamydospore-like structures are not true chlamydospores but are produced by inflation of actively growing hyphae by developing vacuoles in cells. In conclusion, observation of development of chlamydospore-like structures in culture media is the simplest method for identification of T. tonsurans.

  19. Ovicidal activity of different concentrations of Pochonia chlamydosporia chlamydospores on Taenia taeniaeformis eggs.

    Science.gov (United States)

    Braga, F R; Silva, A R; Carvalho, R O; Araújo, J V; Pinto, P S A

    2011-03-01

    Three concentrations of chlamydospores of the nematophagous fungus Pochonia chlamydosporia (1000, 10,000 and 20,000 per Petri dish) were evaluated in vitro on Taenia taeniaeformis eggs. Chlamydospores at each concentration were cultured in two different media: 2% water-agar (2%WA) and 2% corn-meal-agar (2%CMA). Taenia taeniaeformis eggs were plated in each chlamydospore concentration in 2%WA and 2%CMA (treated groups) and without fungus (control group). Eggs were removed from each Petri dish at intervals of 7, 14 and 21 days and classified according to ovicidal activity (type 1, type 2 and type 3 effects). Plates containing 2%CMA showed the highest percentages for type 3 effect (81.3%) on the 21st day of observation. A difference (P taeniaeformis eggs and can be considered a potential biological control agent for this cestode.

  20. Predatory activity of chlamydospores of the fungusPochonia chlamydosporia on Toxocara caniseggs under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Juliana Milani Araujo

    Full Text Available The objective of this study was to use chlamydospores of the fungusPochonia chlamydosporia (isolates VC1 and VC4 against Toxocara canis eggs in a 15-day in vitro assay. One thousand T. canis eggs were placed in Petri dishes containing 2% water agar medium with different concentrations of chlamydospores (1,000, 10,000 or 100,000 of each fungal isolate of P. chlamydosporia (treated groups and 1,000 eggs in Petri dishes without fungus (control group. Egg counts were performed to determine the ovicidal activity, which was classified as three effect levels: type 1, type 2 and type 3. Significant differences (P < 0.01 in egg destruction were found in comparison with the control group. The highest percentage of egg destruction was found in plates containing 100,000 chlamydospores (68.5% for VC1 and 70.5% for VC4. Chlamydospores of P. chlamydosporiawere effective in destroying T. canis eggs and may contribute in the future towards combating the eggs of this parasite.

  1. The effect of temperature on germination of chlamydospores of Phytophthora ramorum.

    Science.gov (United States)

    Tooley, Paul W; Browning, Marsha; Leighty, Robert M

    2014-01-01

    Mycelium-free chlamydospores of 12 isolates of P. ramorum representing three clonal lineages were produced with a method involving incubation in nonsterile sand at 20 C in darkness for 30 d. Chlamydospores were incubated on selective agar medium at 5, 10, 15, 20, 25 and 30 C and germination assessed after 1, 2, 4, 6 and 8 d incubation. The optimal temperature for germination based on 8 d incubation was 20 C for all three clonal lineages tested (NA1, NA2, EU1). Mean germination rates were 2, 21, 44, 67, 32 and 0 percent at 5, 10, 15, 20, 25 and 30 C respectively for all isolates combined. The highest mean germination rate was scored by isolates of the EU1 clonal lineage at 20 C (85%) after 8 d incubation However, substantial variation was observed among isolates within each clonal lineage. Overall temperatures and days of incubation on which germination was assessed isolates of the NA1 clonal lineage had the lowest mean germination, even though one isolate had the highest germination of any isolate in any lineage. The results indicate that 20 C is the optimal germination temperature for P. ramorum chlamydospores and that a great disparity in germination percentage can exist within isolates, even within a single clonal lineage.

  2. Effects of 60 Cobalt ionizing radiation in morphology and metabolism of yeasts and Chlamydospore of Candida albicans

    Energy Technology Data Exchange (ETDEWEB)

    Grillo, Michel R.F.; Demicheli, Marina C.; Andrade Junior, Heitor F.; Galiesteo Junior, Andres A.J., E-mail: galisteo@usp.br [Universidade de Sao Paulo (IMTSP/USP), Sao Paulo, SP (Brazil). Instituto de Medicina Tropical. Lab. de Protozoologia; Takakura, Cleusa F.H. [Universidade de Sao Paulo (FM/USP), Sao Paulo, SP (Brazil). Departamento de Patologia de Molestias Transmissiveis. Lab. de Patologia; Negro, Gilda M.B. del [Universidade de Sao Paulo (HCFM/USP/IMTSP/LIM-53), Sao Paulo, SP (Brazil). Hospital das Clinicas. Lab. de Micologia; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Candida albicans is a fungus responsible for 80-90% of fungal infections, as the symptoms are similar to those of systemic bacterial infections there is a difficulty for immediate diagnosis. These difficulties can lead to delays of antifungal therapy, which contributes to the high mortality rates associated with this infection. Resistance structures referred to as chlamydospores are very common in the pathogen, representing different cell types that form in response to certain genetic or environmental conditions. Recently, various antifungal agents and new therapeutic strategies have come into use, allowing the fungus to acquire a resistance to the drugs. The use of ionizing radiation has been widely employed for the production of immunogens against various parasites. In this work, we evaluate the effects of gamma radiation ({sup 60}Co) in yeast and chlamydospore of C. albicans with doses ranging from 320 to 10.240 Gy with Cobalt 60. Subsequently the samples were plated and after seven days, the colony forming units (CFU) told. The viability of irradiated cells were evaluated using the Janus green dye. A dose of 6000 Gy was considered ideal for the mitigation of chlamydospore and yeast. The dimorphic change mechanisms of both fungal structures were not harmed. The viability of chlamydospores remained above 70% while the yeast viability remained above 85%. By transmission electron microscopy and fluorescence microscopy may be noted cytoplasmic changes, defects in the cell wall, mitochondria, and the presence of partially preserved vesicles of both morphological forms of C. albicans. Irradiation both chlamydospore as C. albicans yeast allows the suppression of their reproduction, opening the possibility of their use in future candidate immunogens. (author)

  3. [Nematophagous fungi used for the biological control of gastrointestinal nematodes in livestock and administration routes].

    Science.gov (United States)

    Sagüés, María Federica; Purslow, Peter; Fernández, Silvina; Fusé, Luis; Iglesias, Lucía; Saumell, Carlos

    2011-01-01

    The control of gastrointestinal nematodes relies at present mostly on antihelmintic treatments using synthetic molecules. This approach, however, has led to the appearance of resistance to some types of antihelmintics which, together with the need to cut down on the use of chemicals, has fostered the development of other control methods, such as biological control, which is the use of living organisms that are naturally antagonistic to an unwanted species. Among the natural enemies of nematode parasitic larvae is the microfungus Duddingtonia flagrans. Research has shown the ability of this fungus to reduce the number of nematode larvae in faeces, the ability of its chlamydospores to survive the passage through the gastrointestinal tract of livestock and, moreover, to keep its germinative ability, thus facilitating the development of formulations. The present review looks at the species currently used and the different ways of administering already tested nematophagous fungi.

  4. Inoculation with chlamydospores of Trichoderma asperellum SM-12F1 accelerated arsenic volatilization and inlfuenced arsenic availability in soils

    Institute of Scientific and Technical Information of China (English)

    WANG Xiu-rong; SU Shi-ming; ZENG Xi-bai; BAI Ling-yu; LI Lian-fang; DUAN Ran; WANG Ya-nan; WU Cui-xia

    2015-01-01

    Fungi capable of arsenic (As) accumulation and volatilization are hoped to tackle As-contaminated environment in the future. However, little data is available regarding their performances in ifeld soils. In this study, the chlamydospores of Trichoderma asperel um SM-12F1 capable of As resistance, accumulation, and volatilization were inoculated into As-contaminated Chen-zhou (CZ) and Shimen (SM) soils, and subsequently As volatilization and availability were assessed. The results indicated that T. asperel um SM-12F1 could reproduce wel in As-contaminated soils. After cultivated for 42 days, the colony forming units (cfu) of T. asperel um SM-12F1 in CZ and SM soils reached 1010–1011 cfu g–1 fresh soil when inoculated at a rate of 5.0%. Inoculation with chlamydospores of T. asperel um SM-12F1 could signiifcantly accelerate As volatilization from soils. The contents of volatilized As from CZ and SM soils after being inoculated with chlamydospores at a rate of 5.0%for 42 days were 2.0 and 0.6μg kg–1, respectively, which were about 27.5 and 2.5 times higher than their corresponding controls of no inoculation (CZ, 0.1μg kg–1;SM, 0.3μg kg–1). Furthermore, the available As content in SM soils was decreased by 23.7%, and that in CZ soils increased by 3.3%compared with their corresponding controls. Further studies showed that soil pH values signiifcantly decreased as a function of cultivation time or the inoculation level of chlamydospores. The pH values in CZ and SM soils after being inoculated with 5.0%of chlamydospores for 42 days were 6.04 and 6.02, respectively, which were lowered by 0.34 and 1.21 compared with their corresponding controls (CZ, 6.38;SM, 7.23). The changes in soil pH and As-binding fractions after inoculation might be responsible for the changes in As availability. These observations could shed light on the future remediation of As-contaminated soils using fungi.

  5. Inoculating chlamydospores of Trichoderma asperellum SM-12F1 changes arsenic availability and enzyme activity in soils and improves water spinach growth.

    Science.gov (United States)

    Su, Shiming; Zeng, Xibai; Bai, Lingyu; Williams, Paul N; Wang, Yanan; Zhang, Lili; Wu, Cuixia

    2017-05-01

    Arsenic (As)-contaminated agricultural soils threaten crop yields and pose a human health risk. Augmentation of exogenous microorganisms exhibiting plant-growth promoting and As speciation changing shows potential to improve crop growth and change soil As availability. Trichoderma asperellum SM-12F1 exhibiting both traits was developed into chlamydospores to improve its persistence in contaminated soils. After inoculation, As availability and enzyme activity in two types of soils and the growth as well as As uptake of water spinach (Ipomoea aquatic Forsk.) were investigated. The results indicated that inoculation significantly improved water spinach growth in both soils. Inoculating chlamydospores at 5% significantly increased As concentration (139%), bioconcentration factor (150%), and translocation factor (150%) in water spinach grown in Chenzhou (CZ) soils, while no significant change for these in Shimen (SM) soils. Inoculating chlamydospores at 5% caused a significant increase (16%) of available As content in CZ soils, while a significant decrease (13%) in SM soils. Inoculation significantly caused As methylation in both soils, while significant As reduction merely observed in CZ soils. The differential changes in available As contents in both soils were attributed to the soil pH, As fractionations and speciation characteristics. Furthermore, Inoculating chlamydospores at 5% significantly improved the activities of β-glucosidase (155%), chitinase (211%), and phosphatase (108%) in SM soils, while significant decreases in β-glucosidase (81%), phosphatase (54%), aminopeptidase (60%), and catalase (67%) in CZ soils. Bioaugmentation and As availability change were responsible for this result. These observations will be helpful for the application of fungal chlamydospores in the future bioremediation. Copyright © 2017. Published by Elsevier Ltd.

  6. Removal of phenol in phenolic resin wastewater by a novel biomaterial: the Phanerochaete chrysosporium pellet containing chlamydospore-like cells.

    Science.gov (United States)

    Hailei, Wang; Ping, Li; Yu, Qin; Hui, Yang

    2016-06-01

    A novel biomaterial, the Phanerochaete chrysosporium pellet (CP) composed of chlamydospore-like cells (CLCs), was prepared and its potential in treating phenolic resin wastewater was evaluated. CP possesses higher phenol removal ability in contrast with mycelial pellets of P. chrysosporium, and CLC can be seen as the naturally immobilized enzymes. At shake-flask level, the ideal pH value, temperature, and inoculation quantity of CP for treatment of 1430 mg/l phenol wastewater were pH 4-6, 30 °C, and 5.0 g/l, respectively, and the maximum specific removal rate, 41.1 mg phenol/g CP/h, was obtained in fixed bed reactor (FBR) when the flow rate of wastewater was 3.4 l/h. During the treatment, FBR harbored amounts of bacteria (135 genera) and eukaryotes, as analyzed by metagenomic sequencing. Bacterial pollution not only decreased reactor performance but also had a negative impact on reusability of CP. Hot water treatment (80-85 °C) is effective to inhibit bacterial pollution, and heat resistance of CLC makes the repeated regrowing of CP be feasible. This work presents an innovative and low-cost biomaterial for phenol removal and will be helpful for the practical application of P. chrysosporium in wastewater treatment.

  7. [Effects of pesticides and plant bio-stimulants on the germination of chlamydospores and in vitro development of the nematophagous fungus Pochonia chlamydosporia].

    Science.gov (United States)

    Ceiro, Wilson G; Arévalo, Jersys; Hidalgo-Díaz, Leopoldo

    2015-01-01

    The effects of pesticides and plant bio-stimulants used in protected vegetable production systems on the fungus Pochonia chlamydosporia are unknown. The effectiveness of P. chlamydosporia against Meloidogyne spp. could be affected by products used in protected vegetable production systems. Two in vitro assays were carried out to evaluate any potential effect that pesticides and bio-stimulants often used in these systems could have on the fungus. The effect on chlamydospore germination was evaluated in a first assay, and mycelia growth and sporulation in a second. With these results, the compatibility of each product with the fungus was determined. Chlamydospores germination was over 50% with the control, FitoMas E, Biobras-16 and Amidor. Lower results were observed with other products, with some of them even inhibiting germination completely. Fungal growth was potentiated by Biobras-16 to 106.23%, promoted up to 50-100% by the control, FitoMas E and Cuproflow, and was below 50% with the rest of the products.Cipermetrina, Benomilo, Zineb, Mitigan, Karate, FitoMas E and Amidor promoted fungal sporulation, which was below 50% with Cuproflow and completely inhibited by the other products. Fifty-four percent of the products evaluated were compatible with P. chlamydosporia, while 8% were toxic and 38%, very toxic. Cipermetrina, Karate, Amidor, Benomilo, Zineb, Mitigan and FitoMas E were compatible with P. chlamydosporia. If it is necessary to use any of the other products for integrated pest management in protected vegetable production systems, it is recommended to avoid direct contact with P. chlamydosporia. Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  8. lnhibition of Chlamydospore Germination and Mycelial Growth of Trichoderma spp. by Chemical Fungicides%化学杀菌剂对木霉菌厚垣孢子萌发及菌丝生长的抑制作用

    Institute of Scientific and Technical Information of China (English)

    张林; 蒋细良; 杨晓燕; 李梅; 陈书华

    2015-01-01

    For exploring the influences of application and residue of chemical fungi-cides on chlamydospore preparations of Trichoderma spp., the effects of seven chemical fungicides on chlamydospore germination and mycelia growth of two bio-control fungi T. harzianum 610 and T. longibrachiatum 758 were studied. Carben-dazim, tebuconazole and difenoconazole showed strong toxicities, thiram and car-boxin showed moderate toxicities, pentachloronitrobenzene and metalaxyl showed weak toxicities to the tested two strains. Mycelia growth of the two strains was more sensitive to most tested fungicides than those of chlamydospore germination. Chlamydospore germination of 610 was more sensitive to tested fungicides than those of 758, and mycelia growth of 758 was more sensitive to most tested fungi-cides than those of 610. Among the seven fungicides, 98% carbendazim had the strongest effects (EC50 values were 1.64 and 0.05 μg/ml), and 70% pentachloroni-trobenzene had the weakest effects (EC50 values were 1.64 and 0.05 μg/ml) for chlamydospore germination and mycelia growth of 610. As for 758, 98% carbendaz-im had the strongest inhibitory effects and 95% metalaxyl had the weakest inhibitory for chlamydospore germination of 758 (EC50 values were 0.62 and 1 108.61 μg/ml respectively), whereas 96.2% tebuconazole showed the strongest inhibitory effects for mycelia growth of 758 (EC50 value was 0.32 μg/ml), and 95% metalaxyl was the weakest (EC50 value was 1 206.29 μg/ml). According to the applied concentration of different fungicides in practice, we concluded that chlamydospore preparations of 610 and 758 could not be combined with carbendazim, tebuconazole, thiram and carboxin for control ing plant diseases, and the pesticide residues to the biocontrol effects should be kept in mind. Chlamydospore preparations of 610 and 758 can be combined with pentachloronitrobenzene and difenoconazole for control ing plant dis-eases, 758 chlamydospore preparations and germinated chlamydospore of

  9. Evaluación de un método combinado de control de la hemoncosis ovina en condiciones controladas

    OpenAIRE

    Fabián Leonardo Arroyo Balán; Pedro Mendoza de Gives; Maria Eugenia López Arellano; Enrique Liébano Hernández; Víctor Vázquez Prats; Estefan Miranda Miranda; Ana Maria Ortiz de Montellano Nolasco

    2008-01-01

    Se evaluó un método antiparasitario combinado, mediante el uso de albendazol y del hongo Duddingtonia flagrans, en ovinos infectados con Haemonchus contortus. El experimento duró 90 días. Se formaron cuatro grupos de 10 corderos cada uno, infectados con H. contortus y recibieron los siguientes tratamientos: Grupo 1, albendazol (7.5 mg/kg), a los días 0, 30 y 60 del experimento; Grupo 2, recibió 1x106 clamidosporas de D. flagrans por kg, por vía oral; Grupo 3, recibió la combinación de ambos t...

  10. Predatory activity of chlamydospores of the fungus Pochonia chlamydosporia on Toxocara canis eggs under laboratory conditions Atividade predatória de clamidósporos do fungo Pochonia chlamydosporia sobre ovos de Toxocara canis em condições laboratoriais

    Directory of Open Access Journals (Sweden)

    Juliana Milani Araujo

    2013-03-01

    Full Text Available The objective of this study was to use chlamydospores of the fungus Pochonia chlamydosporia (isolates VC1 and VC4 against Toxocara canis eggs in a 15-day in vitro assay. One thousand T. canis eggs were placed in Petri dishes containing 2% water agar medium with different concentrations of chlamydospores (1,000, 10,000 or 100,000 of each fungal isolate of P. chlamydosporia (treated groups and 1,000 eggs in Petri dishes without fungus (control group. Egg counts were performed to determine the ovicidal activity, which was classified as three effect levels: type 1, type 2 and type 3. Significant differences (P O objetivo do trabalho foi utilizar clamidósporos do fungo Pochonia chlamydosporia (isolados VC1 e VC4 na destruição de ovos de Toxocara canis, num ensaio in vitro, realizado no intervalo de 15 dias. Em cada placa de Petri com ágar-água 2% foram vertidos 1.000 ovos de T. canis em 1.000, 10.000 ou 100.000 clamidósporos de cada isolado do fungo (grupos tratados. Foram realizadas as contagens para verificar a atividade ovicida, classificada em três níveis de efeito: tipo 1, tipo 2 e tipo 3. Os resultados demonstraram que houve diferença significativa (P < 0,01 na destruição dos ovos em relação aos ovos observados nas placas do grupo controle. O maior percentual de ovos destruídos foi observado nas placas contendo 100.000 clamidósporos (68,5% para VC1 e 70,5% para VC4. Clamidósporos do fungo P. chlamydosporia foram efetivos na destruição dos ovos de T. canis podendo contribuir no futuro para o combate aos ovos deste parasito.

  11. Fungal Antagonism Assessment of Predatory Species and Producers Metabolites and Their Effectiveness on Haemonchus contortus Infective Larvae

    Directory of Open Access Journals (Sweden)

    Manoel Eduardo Silva

    2015-01-01

    Full Text Available The objective of this study was to assess antagonism of nematophagous fungi and species producers metabolites and their effectiveness on Haemonchus contortus infective larvae (L3. Assay A assesses the synergistic, additive, or antagonistic effect on the production of spores of fungal isolates of the species Duddingtonia flagrans, Clonostachys rosea, Trichoderma esau, and Arthrobotrys musiformis; Assay B evaluates in vitro the effect of intercropping of these isolates grown in 2% water-agar (2% WA on L3 of H. contortus. D. flagrans (Assay A produced 5.3 × 106 spores and associated with T. esau, A. musiformis, or C. rosea reduced its production by 60.37, 45.28, and 49.05%, respectively. T. esau produced 7.9 × 107 conidia and associated with D. flagrans, A. musiformis, or C. rosea reduced its production by 39.24, 82.27, and 96.96%, respectively. A. musiformis produced 7.3 × 109 spores and associated with D. flagrans, T. esau, or C. rosea reduced its production by 99.98, 99.99, and 99.98%, respectively. C. rosea produced 7.3 × 108 conidia and associated with D. flagrans, T. esau, or A. musiformis reduced its production by 95.20, 96.84, and 93.56%, respectively. These results show evidence of antagonism in the production of spores between predators fungi.

  12. Fungal Antagonism Assessment of Predatory Species and Producers Metabolites and Their Effectiveness on Haemonchus contortus Infective Larvae.

    Science.gov (United States)

    Silva, Manoel Eduardo; Braga, Fabio Ribeiro; de Gives, Pedro Mendoza; Millán-Orozco, Jair; Uriostegui, Miguel Angel Mercado; Marcelino, Liliana Aguilar; Soares, Filippe Elias de Freitas; Araújo, Andréia Luiza; Vargas, Thainá Souza; Aguiar, Anderson Rocha; Senna, Thiago; Rodrigues, Maria Gorete; Froes, Frederico Vieira; de Araújo, Jackson Victor

    2015-01-01

    The objective of this study was to assess antagonism of nematophagous fungi and species producers metabolites and their effectiveness on Haemonchus contortus infective larvae (L3). Assay A assesses the synergistic, additive, or antagonistic effect on the production of spores of fungal isolates of the species Duddingtonia flagrans, Clonostachys rosea, Trichoderma esau, and Arthrobotrys musiformis; Assay B evaluates in vitro the effect of intercropping of these isolates grown in 2% water-agar (2% WA) on L3 of H. contortus. D. flagrans (Assay A) produced 5.3 × 10(6) spores and associated with T. esau, A. musiformis, or C. rosea reduced its production by 60.37, 45.28, and 49.05%, respectively. T. esau produced 7.9 × 10(7) conidia and associated with D. flagrans, A. musiformis, or C. rosea reduced its production by 39.24, 82.27, and 96.96%, respectively. A. musiformis produced 7.3 × 10(9) spores and associated with D. flagrans, T. esau, or C. rosea reduced its production by 99.98, 99.99, and 99.98%, respectively. C. rosea produced 7.3 × 10(8) conidia and associated with D. flagrans, T. esau, or A. musiformis reduced its production by 95.20, 96.84, and 93.56%, respectively. These results show evidence of antagonism in the production of spores between predators fungi.

  13. Control of infective larvae of gastrointestinal nematodes in heifers using different isolates of nematophagous fungi.

    Science.gov (United States)

    Silva, Manoel Eduardo da; Araújo, Jackson Victor de; Braga, Fabio Ribeiro; Freitas Soares, Filippe Elias de; Rodrigues, Daniel Sobreira

    2013-01-01

    The effect of different nematophagous fungi [Duddingtonia flagrans (AC001 and CG722) and Monacrosporium thaumasium (NF34)] with regard to controlling infective larvae (L3) of nematodes after gastrointestinal transit in female cattle (3/4 Holstein × Zebu) was evaluated. A total of 24 pubescent female cattle were used, weighing approximately 320 kg each one. There were three treatment groups, each contained six animals that received 150 g of pellets (0.2 g of mycelium), orally in a single dose, in a sodium alginate matrix containing mycelial mass of the fungus D. flagrans (AC001 or CG722) or M. thaumasium (NF34); and one control group (without fungi). Fecal samples were collected from the animals at intervals of 12, 15, 18, 21, 24, 48, and 72 hours. At the end of 17 days, the L3 not subjected to predation were recovered by means of the Baermann method. The fungal isolates tested were capable of destroying the L3 after gastrointestinal transit. It was observed that within 72 hours, the isolates AC001, CG722, and NF34 showed a higher predatory activity (81.2%, 97.3%, and 98.3%, respectively). The results justify the need for studies in the field, and over longer intervals, in order to observe the efficiency of the fungus D. flagrans, or even M. thaumasium, for environmental control over nematodes in naturally infected cattle.

  14. Predatory activity of Butlerius nematodes and nematophagous fungi against Haemonchus contortus infective larvae.

    Science.gov (United States)

    Silva, Manoel Eduardo da; Uriostegui, Miguel Angel Mercado; Millán-Orozco, Jair; Gives, Pedro Mendoza de; Hernández, Enrique Liébano; Braga, Fabio Ribeiro; Araújo, Jackson Victor de

    2017-01-01

    The purpose of this study was to evaluate the predatory activity of the nematode Butlerius spp. and fungal isolates of Duddingtonia flagrans, Clonostachys rosea, Arthrobotrys musiformis and Trichoderma esau against H. contortus infective larvae (L3) in grass pots. Forty-eight plastic gardening pots containing 140 g of sterile soil were used. Panicum spp. grass seeds (200 mg) were sown into each pot and individually watered with 10 mL of tap water. Twelve days after seeding, the pots were randomly divided into 6 groups (n=8). Two thousand H. contortus infective larvae (L3) were added to each group. Additionally, the following treatments were established: Group 1 - 2000 Butlerius spp. larvae; group 2 - A. musiformis (1x107 conidia); group 3 - T. esau (1x107 conidia); group 4 - C. rosea (1x107 conidia), group 5 - D. flagrans (1x107conidia) and Group 6 - no biological controller (control group). The larval population of H. contortus exposed to Butlerius spp. was reduced by 61.9%. Population reductions of 90.4, 66.7, 61.9 and 85.7% were recorded in the pots containing A. musiformis, T. esau, C. rosea and D. flagrans, respectively. The results of this study indicate that the predatory nematode Butlerius spp. and the assessed fungi display an important predatory activity can be considered suitable potential biological control agents.

  15. Predatory activity of Butlerius nematodes and nematophagous fungi against Haemonchus contortus infective larvae

    Directory of Open Access Journals (Sweden)

    Manoel Eduardo da Silva

    Full Text Available Abstract The purpose of this study was to evaluate the predatory activity of the nematode Butlerius spp. and fungal isolates of Duddingtonia flagrans, Clonostachys rosea, Arthrobotrys musiformis and Trichoderma esau against H. contortus infective larvae (L3 in grass pots. Forty-eight plastic gardening pots containing 140 g of sterile soil were used. Panicum spp. grass seeds (200 mg were sown into each pot and individually watered with 10 mL of tap water. Twelve days after seeding, the pots were randomly divided into 6 groups (n=8. Two thousand H. contortus infective larvae (L3 were added to each group. Additionally, the following treatments were established: Group 1 – 2000 Butlerius spp. larvae; group 2 – A. musiformis (1x107 conidia; group 3 – T. esau (1x107 conidia; group 4 – C. rosea (1x107 conidia, group 5 – D. flagrans (1x107conidia and Group 6 – no biological controller (control group. The larval population of H. contortus exposed to Butlerius spp. was reduced by 61.9%. Population reductions of 90.4, 66.7, 61.9 and 85.7% were recorded in the pots containing A. musiformis, T. esau, C. rosea and D. flagrans, respectively. The results of this study indicate that the predatory nematode Butlerius spp. and the assessed fungi display an important predatory activity can be considered suitable potential biological control agents.

  16. Mixed Production of Filamentous Fungal Spores for Preventing Soil-Transmitted Helminth Zoonoses: A Preliminary Analysis

    Directory of Open Access Journals (Sweden)

    M. S. Arias

    2013-01-01

    Full Text Available Helminth zoonoses are parasitic infections shared by humans and animals, being the soil-transmitted helminths (STHs mainly caused by roundworms (ascarids and hookworms. This study was aimed to assess the individual and/or mixed production of two helminth-antagonistic fungi, one ovicide (Mucor circinelloides and other predator (Duddingtonia flagrans. Fungi were grown both in Petri plates and in a submerged culture (composed by water, NaCl, Na2HPO4 · 12 H2O, and wheat (Triticum aestivum. A Fasciola hepatica recombinant protein (FhrAPS was incorporated to the cultures to improve fungal production. All the cultured plates showed fungal growth, without difference in the development of the fungi when grown alone or mixed. High counts of Mucor spores were produced in liquid media cultures, and no significant differences were achieved regarding single or mixed cultures, or the incorporation of the FhrAPS. A significantly higher production of Duddingtonia spores after the incorporation of the FhrAPS was observed. When analyzing the parasiticide efficacy of the fungal mixture, viability of T. canis eggs reduced to 51%, and the numbers of third stage cyathostomin larvae reduced to 4%. It is concluded, the capability of a fungal mixture containing an ovicide (Mucor and a predator species (Duddingtonia for growing together in a submerged medium containing the FhrAPS offers a very interesting tool for preventing STHs.

  17. Control of Strongyloides westeri by nematophagous fungi after passage through the gastrointestinal tract of donkeys Controle de Strongyloides westeri por fungos nematófagos após trânsito gastrintestinal em jumentas

    Directory of Open Access Journals (Sweden)

    Juliana Milani Araujo

    2012-06-01

    Full Text Available Strongyloides westeri is the most prevalent nematode among equines aged up to four months and causes gastrointestinal disorders. The objective of this study was to observe the control of infective S. westeri larvae (L3 by the nematophagous fungi Duddingtonia flagrans (AC001 and Monacrosporium thaumasium (NF34 after passage through the gastrointestinal tract of female donkeys. Twelve dewormed female donkeys that were kept in stables were used. Two treatment groups each comprising four animals received orally 100 g of pellets made of sodium alginate matrix containing a mycelial mass of either D. flagrans (AC001 or M. thaumasium (NF34. The control group consisted of four animals that received pellets without fungus. Feces samples were then collected from the animal groups at different times (after 12, 24, 48 and 72 hours. These feces were placed in Petri dishes containing 2% water-agar medium and 1000 L3 of S. westeri. AC001 and NF34 isolates showed the ability to destroy the L3, after gastrointestinal transit, thus demonstrating their viability and predatory activity.O Strongyloides westeri é o nematóide de maior prevalência entre equídeos com idade até quatro meses, causando distúrbios gastrintestinais. O objetivo do presente trabalho foi observar o controle de larvas infectantes (L3 de Strongyloides westeri pelos fungos nematófagos Duddingtonia flagrans (AC001 e Monacrosporium thaumasium (NF34 após trânsito gastrintestinal em jumentas. Foram utilizadas 12 jumentas, estabuladas e previamente vermifugadas. A seguir, dois grupos tratados, contendo cada um 4 animais receberam por via oral 100 g de péletes em matriz de alginato de sódio, contendo massa miceliana dos fungos D. flagrans (AC001 ou M. thaumasium (NF34. O grupo controle foi constituído de 4 animais que receberam péletes sem fungo. A seguir, amostras de fezes dos grupos de animais foram coletadas em distintos intervalos de horas (12, 24, 48 e 72. Essas fezes foram vertidas em

  18. Biological control of gastro-intestinal nematodes--facts, future, or fiction?

    Science.gov (United States)

    Larsen, M; Nansen, P; Grønvold, J; Wolstrup, J; Henriksen, S A

    1997-11-01

    The potential of using fungi to prevent nematodosis caused by parasites with free-living larval stages is well documented today. In this respect Duddingtonia flagrans, a net-trapping, nematode-destroying fungus, appears to be the most promising candidate. Laboratory experiments and in-vivo studies, where fungal spores have survived passage through the gastro-intestinal tract of cattle and horses, plus field studies with cattle, horses and pigs, demonstrate significant reduction in the number of infective larvae that develop in the faecal environment. In field trials this reduction subsequently leads to reduced infectivity of herbage and also reduced worm burdens in grazing animals. A status of the present situation, primarily based upon work performed in Denmark within the last 6-8 years, plus an outlook for practical implementation of an integrated control strategy including the use of nematode-destroying fungi in the future is discussed.

  19. Interaction and ovicidal activity of nematophagous fungus Pochonia chlamydosporia on Taenia saginata eggs.

    Science.gov (United States)

    Araújo, Juliana M; Araújo, Jackson V; Braga, Fabio R; Carvalho, Rogério O; Silva, André R; Campos, Artur K

    2009-04-01

    The ovicidal activity of the nematophagous fungi Pochonia chlamydosporia (isolates VC1 and VC4), Duddingtonia flagrans (isolate AC001) and Monacrosporium thaumasium (isolate NF34) on Taenia saginata eggs was evaluated under laboratory conditions. T. saginata eggs were plated on 2% water-agar with fungal isolates and controls without fungus and examined after 5, 10 and 15 days. At the end of the experiment P. chlamydosporia showed ovicidal activity against T. saginata eggs (p<0.05), mainly for internal egg colonization with results of 12.8% (VC1) and 2.2% (VC4); 18.1% (VC1) and 7.0% (VC4); 9.76% (VC1) and 8.0% (VC4) at 5, 10 and 15 days, respectively. The other fungi showed only lytic effect without morphological damage to the eggshell. Results demonstrated that P. chlamydosporia was effective in vitro against T. saginata eggs unlike the other fungi.

  20. Screening of different sample types associated with sheep and cattle for the presence of nematophagous fungi in China.

    Science.gov (United States)

    Cai, Kui-Zheng; Liu, Jun-Lin; Liu, Wei; Wang, Bo-Bo; Xu, Qiang; Sun, Long-Jie; Chen, Ming-Yue; Zhao, Ming-Wang; Wu, Jia-Yan; Li, Xiao-Shan; Yang, Jing; Wei, Shuan; Chen, Chun-Rong; Ma, Zhong-Ren; Xu, Chun-Lan; Wang, Feng; Hu, Qian-Lin; Fang, Wen-Xiu; Zheng, Tian-Hui; Wang, Yue-Ying; Zhu, Wen-Long; Li, Dan; Li, Qing; Zhang, Chao; Cai, Bing; Wang, Fan; Yang, Zai-Yun; Liu, Yan-Qiu

    2016-03-01

    A total of 1502 samples, including feces of sheep (793) and cattle (348), pasture soil (118), dung compost (147) and barn soil (96), were examined between October 2012 and August 2014 to discover potential strains of nematophagous fungi for the biological control of livestock-parasitic nematodes. These samples were collected from 87 sites located in 48 counties of 20 provinces (autonomous regions/municipalities) of China. Fungi were identified down to a species level. Four hundred and seventy-seven isolates, which were distributed in 8 genera and 28 taxa, were identified as nematophagous fungi. Nematode-trapping fungi included 17 species and one unidentified species of Arthrobotrys, two of Dactylella, Drechslerella dactyloides, and Duddingtonia flagrans. Five identified species and two unidentified species of endoparasitic fungi were isolated. The predominant species from all regions were Arthrobotrys oligospora, followed by Arthrobotrys musiformis, Arthrobotrys (Monacrosporium) thaumasiun, and Arthrobotrys (Monacrosporium) microscaphoides. Species with adhesive networks were the most frequently isolated. Among the endoparasitic fungi, Podocrella harposporifera (Harposporium anguillulae) was the most common species, followed by Harposporium lilliputanum and Harposporium arcuatum. Based on Shannon diversity index, the diversity levels of nematophagous fungi were relatively higher in samples associated with cattle, barn soil, and subtropical monsoon climate zone. Three species isolated from this study, namely, Duddingtonia flagrans, Arthrobotrys salina (Monacrosporium salinum), and Arthrobotrys oligospora var. sarmatica, are newly recorded in China, and 20 species (including one unidentified species) are newly recorded in sheep and cattle barn soils worldwide. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Control of infective larvae of gastrointestinal nematodes in heifers using different isolates of nematophagous fungi Controle de larvas infectantes de nematóides gastrintestinais de novilhas por diferentes isolados dos fungos nematófagos

    Directory of Open Access Journals (Sweden)

    Manoel Eduardo da Silva

    Full Text Available The effect of different nematophagous fungi [Duddingtonia flagrans (AC001 and CG722 and Monacrosporium thaumasium (NF34] with regard to controlling infective larvae (L3 of nematodes after gastrointestinal transit in female cattle (3/4 Holstein × Zebu was evaluated. A total of 24 pubescent female cattle were used, weighing approximately 320 kg each one. There were three treatment groups, each contained six animals that received 150 g of pellets (0.2 g of mycelium, orally in a single dose, in a sodium alginate matrix containing mycelial mass of the fungus D. flagrans (AC001 or CG722 or M. thaumasium (NF34; and one control group (without fungi. Fecal samples were collected from the animals at intervals of 12, 15, 18, 21, 24, 48, and 72 hours. At the end of 17 days, the L3 not subjected to predation were recovered by means of the Baermann method. The fungal isolates tested were capable of destroying the L3 after gastrointestinal transit. It was observed that within 72 hours, the isolates AC001, CG722, and NF34 showed a higher predatory activity (81.2%, 97.3%, and 98.3%, respectively. The results justify the need for studies in the field, and over longer intervals, in order to observe the efficiency of the fungus D. flagrans, or even M. thaumasium, for environmental control over nematodes in naturally infected cattle.No presente estudo, foi avaliado o efeito de diferentes fungos nematófagos [Duddingtonia flagrans (AC001 e CG722 e Monacrosporium thaumasium (NF34] no controle de larvas infectantes (L3 de nematóides após o trânsito gastrointestinal em fêmeas bovinas (3/4 Holandês x Zebu. Um total de 24 fêmeas bovinas pubescentes foram utilizadas, pesando aproximadamente 320 kg cada. Foram utilizados três grupos de tratamento; cada um contendo seis animais que receberam por via oral de 150 g de péletes (0,2 g de micélio, em dose única, em uma matriz de alginato de sódio contendo massa micelial dos fungos D. flagrans (AC001 ou

  2. In vitro susceptibility of nematophagous fungi to antiparasitic drugs: interactions and implications for biological control

    Directory of Open Access Journals (Sweden)

    J. N. Vieira

    Full Text Available Abstract The fast anthelmintic resistance development has shown a limited efficiency in the control of animal’s endoparasitosis and has promoted research using alternative control methods. The use of chemicals in animal anthelmintic treatment, in association with nematophagous fungi used for biological control, is a strategy that has proven to be effective in reducing the nematode population density in farm animals. This study aims to verify the in vitro susceptibility of the nematophagous fungi Arthrobotrys oligospora, Duddingtonia flagrans and Paecilomyces lilacinus against the antiparasitic drugs albendazole, thiabendazole, ivermectin, levamisole and closantel by using the Minimum Inhibitory Concentration (MIC. MICs ranged between 4.0 and 0.031 µg/mL for albendazole, thiabendazole and ivermectin, between 0.937 and 0.117 µg/mL for levamisole, and between 0.625 and 0.034 µg/mL for closantel. The results showed that all antiparasitic drugs had an in vitro inhibitory effect on nematophagous fungi, which could compromise their action as agents of biological control. D. flagrans was the most susceptible species to all drugs.

  3. Coadministration of nematophagous fungi for biological control over gastrointestinal helminths in sheep in the semiarid region of northeastern Brazil.

    Science.gov (United States)

    Vilela, Vinícius Longo Ribeiro; Feitosa, Thais Ferreira; Braga, Fabio Ribeiro; Araújo, Jackson Victor de; Santos, Antonielson dos; Morais, Dayana Firmino de; Souto, Diego Vagner de Oliveira; Athayde, Ana Célia Rodrigues

    2016-05-15

    This study aimed to evaluate coadministration of Duddingtonia flagrans and Monacrosporium thaumasium in a sodium alginate matrix for controlling gastrointestinal helminths in young and adult sheep in the semiarid region of northeastern Brazil. An area of 1ha was divided into two paddocks, in which two experimental groups (fungus and control) were formed, each consisting of six adult females and ten young males. In each group, two subgroups were formed in accordance with the animal category (adult or young). In the fungus group, each animal received 3g of pellets containing 0.6g of fungal mycelium, with 0.3g of D. flagrans and 0.3g of M. thaumasium for each 10 kg of body weight, in their feed twice a week, for six months. In the control group, each animal received 3g of pellets without fungus for each 10 kg of body weight, in their feed twice a week, for six months, serving as a witness group. Reductions in numbers of eggs per gram of feces of 76% among the adult sheep in the fungus group and 83% among the young sheep in the fungus group were observed, in comparison with their respective control subgroups. The groups that received these fungi needed less salvage deworming and presented better packed cell volume percentages, better weight gain and lower levels of L3/kg dry matter in their paddock than the control groups. Thus, it was concluded that coadministration of D. flagrans and M. thaumasium was effective in controlling gastrointestinal helminths of adults and young sheep in the semiarid region of northeastern Brazil.

  4. Anaerobic soil disinfestation reduces survival and infectivity of Phytophthora nicotianae chlamydospores in pepper

    Science.gov (United States)

    Phytophthora nicotianae is the principal causal agent of root and crown rot disease of pepper plants in Extremadura (western Spain), a spring-summer crop in this region. Preplant soil treatment by anaerobic soil disinfestation (ASD) may effectively control plant pathogens in many crop production sys...

  5. 食线虫真菌防治家畜胃肠道线虫研究进展%Progress on Nematophagous Fungi for Biological Control of Gastrointestinal Nematodes in Livestock

    Institute of Scientific and Technical Information of China (English)

    徐春兰; 白振京; 杨静; 吴佳炎; 黎晓珊; 魏栓; 李清; 刘伟; 秦鸽鸽; 王康英; 房少新; 蔡葵蒸; 孙龙杰; 陈明月; 赵明旺

    2014-01-01

    In nature,nematophagous fungi present themselves as natural enemies of gastrointestinal nema-todes.They can be found in all kinds of environments in the world.At present,preliminary achievement has been achieved in the biological control of using nematophagous fungi against parasitic nematodes in ani-mals.In this peper,progress on nematophagous fungi for biological control of gastrointestinal nematodes in livestock was reviewed.In particular,in vitro tests and in vivo tests,and field trial were introduced in bio-logical control of gastrointestinal nematodes in domestic animals.So far,many studies have showed that Duddingtonia flagrans ,with passing through the gastrointestinal tract,is the most potential strain in bi-ological control of animal nematode diseases.It is proposed that for bio-control preparations,some key technologies of large scale production will be broken through to apply the bio-control techniques to live-stock production as early as possible in future.%在自然界,食线虫真菌本身作为动物胃肠线虫的天敌而存在,它们在世界各地各种各样的环境中被发现。目前,利用食线虫真菌对动物寄生线虫的生物防治已取得初步成果,论文介绍了食线虫真菌在家畜胃肠道线虫生物防治方面的研究进展,重点阐述了捕食线虫性真菌对家畜寄生线虫的体内外杀虫试验和田间试验的现状。诸多研究表明,鞭式达丁屯氏菌(Duddingtonia flagrans )由于能通过动物的消化道,因而对控制家畜胃肠道线虫病最具应用潜力。建议今后在规模化生产生防制剂关键技术上取得突破,使其尽快用于畜牧业生产。

  6. Nematophagous fungi from decomposing cattle faeces in Argentina.

    Science.gov (United States)

    Saumell, Carlos Alfredo; Fernández, Alicia Silvina; Fusé, Luis Alberto; Rodríguez, Manuela; Sagüés, María Federica; Iglesias, Lucía Emilia

    2015-01-01

    Biological control of gastrointestinal nematodes of ruminants by use of nematophagous fungi would become part of any livestock parasite integral control system. Identifying autochthonous species that could then be selected for mass production is an important phase in the practical use of biological control. To search for nematophagous fungi with potential use as biological control agents against gastrointestinal nematodes in Argentina. Decomposing cattle faeces sampled in different locations were incubated in water agar 2% with Panagrellus sp. The developed nematophagous fungi were transferred to new water agar 2% plates and then to corn meal agar plates in order to carry out their identification. Fungal diversity and richness were also assessed. Seventeen species from nine genera of nematophagous fungi were found. Twelve species were nematode-trapping fungi and three species plus two fungi identified to genus level corresponded to endoparasitic fungi. Arthrobotrys conoides, Arthrobotrys oligospora, Duddingtonia flagrans, Monacrosporium doedycoides, Arthrobotrys robusta and Drechmeria coniospora were the most frequently isolated species overall in the whole study (6.6%, 5.7%, 5.7%, 5.7%, 4.7% and 4.7%, respectively) although other species were more frequently recorded at local levels such as Arthrobotrys pyriformis (18.8%). Only A. conoides has been previously isolated from ruminant faecal samples in Argentina. Five nematode-trapping fungal species are mentioned for the first time in the Americas D. flagrans and A. conoides, both identified in the present study, are among the most promising ones as biological control agents against gastrointestinal nematodes of ruminants. Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  7. RNA-Seq reveals the molecular mechanism of trapping and killing of root-knot nematodes by nematode-trapping fungi.

    Science.gov (United States)

    Pandit, Ramesh; Patel, Reena; Patel, Namrata; Bhatt, Vaibhav; Joshi, Chaitanya; Singh, Pawan Kumar; Kunjadia, Anju

    2017-04-01

    Nematode-trapping fungi are well known for their inherent potential to trap and kill nematodes using specialized trapping devices. However, the molecular mechanisms underlying the trapping and subsequent processes are still unclear. Therefore, in this study, we examined differential genes expression in two nematode-trapping fungi after baiting with nematode extracts. In Arthrobotrys conoides, 809 transcripts associated with diverse functions such as signal transduction, morphogenesis, stress response and peroxisomal proteins, proteases, chitinases and genes involved in the host-pathogen interaction showed differential expression with fold change (>±1.5 fold) in the presence of nematode extract with FDR (p-value < 0.001). G-proteins and mitogen activated protein kinases are considered crucial for signal transduction mechanism. Results of qRT-PCR of 20 genes further validated the sequencing data. Further, variations in gene expression among Duddingtonia flagrans and A. conoides showed septicity of nematode-trapping fungi for its host. The findings illustrate the molecular mechanism of fungal parasitism in A. conoides which may be helpful in developing a potential biocontrol agent against parasitic nematodes.

  8. Biological control of infective larvae of Ancylostoma spp. in beach sand.

    Science.gov (United States)

    De Mello, Ingrid Ney Kramer; Braga, Fabio R; Monteiro, Thalita S Avelar; Freitas, Leandro G; Araujo, Juliana M; Soares, Filippe E Freitas; Araújo, Jackson V

    2014-01-01

    Geohelminths are parasites that stand out for their prevalence and wide distribution, depending on the soil for their transmission. The aim of this work was to evaluate the predatory capacity of the fungal isolate of the genus Duddingtonia (CG768) on third stage larvae (L3) of Ancylostoma spp. in beach sand under laboratory conditions. In the assay A five treatment groups and 1 control group were formed. The treatment groups contained 5000, 10,000, 15,000, 20,000 or 25,000 chlamydospores of the fungal isolate and 1000 Ancylostoma spp. L3 in pots containing 30g of sand. The control group (without fungus) contained only 1000 Ancylostoma spp. L3 and distilled water in pots with 30g of sand. Evidence of predatory activity was observed at the end of 15 days, where we observed the following percentages of reduction of L3: Group 1 (4.5%); Group 2 (24.5%); Group 3 (59.2%); Group 4 (58.8%); Group 5 (63%). However, difference was noted (p<0.01) only at concentrations 15,000, 20,000 and 25,000 in relation to control group. In the assay B two groups were formed in Petri dishes of 9cm in diameter containing agar water 2% medium. In the treated group, each Petri dish contained 500 Ancylostoma spp. L3 and 5g of sand containing the isolate CG 768 at a concentration of 25,000 chlamydospores/g of sand, and the control group (without fungus) contained only 500 L3. At the end of 7 days the non-predation L3 of Petri dishes using the method of Baermann were recovered. Difference (p<0.01) between groups on reducing the average number of Ancylostoma spp. L3 (percent reduction of 84%) was observed. The results of this study confirm earlier work on the efficiency of the Duddingtonia genus in the control of Ancylostoma spp. infective larvae. Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  9. The Bio-degradation of Atrazine by Chlamydospore of Phanerochaete chrysosporium%黄孢原毛平革菌(Phanerochaete chrysosporium)厚垣孢子降解阿特拉津的探究

    Institute of Scientific and Technical Information of China (English)

    王莹; 秦雨; 李慧; 王海磊

    2016-01-01

    阿特拉津(atrazine)是一类普遍存在于环境中且难降解的污染物.本文探究了黄孢原毛平革菌(Phanerochaete chrysosporium)厚垣孢子对阿特拉津降解的最佳条件,包括温度、摇床转速、初始培养基pH及接种量.并在大田土壤盆栽实验中,研究P.chrysosporium厚垣孢子和土壤土著微生物对土壤中阿特拉津的降解情况.结果表明:P.chrysosporium厚垣孢子可以有效去除阿特拉津,在33℃、转速为180 r· min-1、pH值为7.0、接种量是4 g·L-1时,去除效果最好,去除率达90.77%.土壤盆栽实验结果表明:施用P.chrysosporium厚垣孢子28 d后,非灭菌土壤中阿特拉津去除率为97.8%,其中P.chrysosporium的降解贡献最为突出,去除能力为59.3%.而土著土壤微生物的去除率仅为20.7%,表明P.chrysosporium厚垣孢子对AT降解效果明显.

  10. A designated centre for people with disabilities operated by Brothers of Charity Services Galway, Galway

    LENUS (Irish Health Repository)

    Palige, Katja

    2013-04-15

    Candida albicans and Candida dubliniensis are pathogenic fungi that are highly related but differ in virulence and in some phenotypic traits. During in vitro growth on certain nutrient-poor media, C. albicans and C. dubliniensis are the only yeast species which are able to produce chlamydospores, large thick-walled cells of unknown function. Interestingly, only C. dubliniensis forms pseudohyphae with abundant chlamydospores when grown on Staib medium, while C. albicans grows exclusively as a budding yeast. In order to further our understanding of chlamydospore development and assembly, we compared the global transcriptional profile of both species during growth in liquid Staib medium by RNA sequencing. We also included a C. albicans mutant in our study which lacks the morphogenetic transcriptional repressor Nrg1. This strain, which is characterized by its constitutive pseudohyphal growth, specifically produces masses of chlamydospores in Staib medium, similar to C. dubliniensis. This comparative approach identified a set of putatively chlamydospore-related genes. Two of the homologous C. albicans and C. dubliniensis genes (CSP1 and CSP2) which were most strongly upregulated during chlamydospore development were analysed in more detail. By use of the green fluorescent protein as a reporter, the encoded putative cell wall related proteins were found to exclusively localize to C. albicans and C. dubliniensis chlamydospores. Our findings uncover the first chlamydospore specific markers in Candida species and provide novel insights in the complex morphogenetic development of these important fungal pathogens.

  11. Fungi from the Lower Carboniferous of central France

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, T.N.; Galtier, J.; Axsmith, B.J. (Ohio State University, Columbus, OH (United States). Dept. of Plant Biology)

    1994-09-01

    Chlamydospores and sporocarps (Roannaisia bivitilis gen. et sp. nov.) are described from late Visean permineralized plant material collected from the Roannais area of central France. Chlamydospores are slightly elongate and several show a short segment of the hyphal attachment. Each chlamydospore contains a thin-walled spore; mycoparasites appear to be present in some spores. Also present in the peat matrix are spherical sporocarps up to 600[mu]m in diameter. The wall is constructed of two layers of interwoven, non-septate, irregularly-branched hyphae. The sporocarp lumen contains a single, multilayered spore. The systematic affinities of both fungi are discussed.

  12. 绿色粘帚霉厚垣孢子产生条件及其对柑橘绿霉病的防治效果研究%Chlamydospore Production Conditions of Gliocladium virens and It's Control Effect on Penicillium digitatum

    Institute of Scientific and Technical Information of China (English)

    李勇; 文成敬

    2013-01-01

    [目的]以绿色粘帚霉菌株UV-44为对象,研究不同培养基、pH、培养时间和温度对厚垣孢子产量影响及其对柑橘绿霉病的室内防效.[方法]采用摇瓶震荡培养菌株,血球计数板计数厚垣孢子数;室内贮藏时浸果后单果独立包装,以清水和施宝克为对照,研究厚垣孢子悬液、分生孢子悬液和发酵原液对柑橘绿霉病的相对防效.[结果]UV-44厚垣孢子产量最高的培养基、pH、培养时间和温度分别是燕麦片液体培养基、pH 10、13 d和30℃,该条件下产生厚垣孢子浓度为1.52×1011个/L;室内贮藏30 d、60 d和90 d后,厚垣孢子相对防效随时间增加,分生孢子悬液和发酵原液低则逐渐降低.[结论]绿色粘帚霉厚垣孢子具有重要的生防价值.

  13. Three improved Citrullus lanatus var. citroides lines USVL246-FR2, USVL252-FR2, and USVL335-FR2, with resistance to Fusarium oxysporum f. sp. niveum race 2

    Science.gov (United States)

    Fusarium wilt (FW) is a major disease of watermelon in North America and around the world. Control of this disease is difficult because the soil-borne causal agent Fusarium oxysporum f. sp. niveum (Fon) produces chlamydospores that remain infectious in the soil for many years. Although, various le...

  14. Vesicular-arbuscular mycorrhizae established with Glomus fasciculatus spores isolated from the feces of cricetine mice

    Science.gov (United States)

    Frederick M. Rothwell; Coleman Holt

    1978-01-01

    Cricetine mice were trapped on two revegetated surface-mined areas - one with a freshly seeded grass-legume cover and one with an early successional grass-forb cover. Chlamydospores of Glomus fasciculatus isolated from the feces of these animals produced representative endomycorrhizae with corn under greenhouse conditions.

  15. PHYTOPHTHORA MEGAKARYA: A REVIEW ON ITS STATUS AS A ...

    African Journals Online (AJOL)

    ACSS

    2015-02-23

    Feb 23, 2015 ... Chlamydospores are the principal long-term survival structures of ...... Awuah, R. T. 1994. In vivo use of ... Bae, H., Bowers, J.H., Tooley, P.W. and Bailey,. B.A. 2005. ... Estados da Bahia e Espirito Santo, Brasil. Fitopatologia ...

  16. Polyphasic taxonomy of the heat resistant ascomycete genus Byssochlamys and its Paecilomyces anamorphs

    DEFF Research Database (Denmark)

    Samson, R.A.; Houbraken, J.; Varga, J.

    2009-01-01

    - and macromorphological characters are valuable for identification purposes, including the shape and size of conidia and ascospores, presence and ornamentation of chlamydospores, growth rates on MEA and CYA and acid production on CREA. A dichotomous key is provided for species identification based on phenotypical...

  17. Enhancement of Plant Establishment on Dredged Material Sites with Mycorrhizal Fungi and Clay Amendments

    Science.gov (United States)

    1989-10-01

    was added to ea,’h pot to deliver 1.5 x 104 chlamydospores/pot of each fungal species. Fig- ure I illustrates the placement of VAM inoculum for host...of Sotany, Vol 66, pp 14-18. Nicolson, T. H., and Johnston, C. 1979. "Mycorrhizae in the Gramineae, Ill. ;cmrus fuicuatus as the Endophyte of Pioneer

  18. Biotechnology of Aureobasidium pullulans: A phylogenetic perspective

    Science.gov (United States)

    Aureobasidium pullulans is a fungus historically included among the "black yeasts." Although many strains are predominantly yeast-like, the species is actually polymorphic, exhibiting complex forms ranging from blastic conidia and swollen cells to pseudophyphae, hyphae, and chlamydospores. A. pull...

  19. Cladobotryum-Konidienformen von Hypomyces-Arten

    NARCIS (Netherlands)

    Gams, W.; Hoozemans, A.C.M.

    1970-01-01

    The genus Cladobotryum Nees is characterized by mostly verticillately branched conidiophores with phialides, dry, one-celled or pluricellular conidia in heads or irregular chains, and pluricellular chlamydospores or sclerotia. Eight species are considered. In four of them the corresponding Hypomyces

  20. A comparative study of carrier state of Candida and its speciation in oral flora – Among healthy individuals, persons with DM and HIV sero positive individuals

    OpenAIRE

    M Bharathi; Anaparthy Usha Rani; Cautha Sandhya

    2012-01-01

    The aim was to determine colonization rate of candida in oral cavity of healthy individuals, diabetics and HIV seropositive individuals.Material and methods: Samples were collected from oral cavity of 50 HIV sero positive individuals, 50 diabetics and 50 healthy individuals by swabbing palatal mucosa, dorsum of tongue and buccal mucosa with a sterile swab. Samples were processed by inoculating on Hi Chrome Agar and speciation was done by growth on Hi Chrome agar, germ tube test, chlamydospore...

  1. Identification of Candida albicans by using different culture medias and its association in potentially malignant and malignant lesions

    Directory of Open Access Journals (Sweden)

    Sonal Saigal

    2011-01-01

    Full Text Available Background and Objective: The present study evaluates the association of Candida albicans with normal control group, potentially malignant and malignant lesions of oral cavity by using two different liquid culture media. Materials and Methods: Saliva was collected and biopsy was taken only from those clinically suspected potentially malignant and malignant lesions for histopathological diagnosis. Saliva samples were inoculated for fungal growth in Sabouraud′s dextrose agar and culture-positive samples had undergone for Germ tube test. Germ tube-positive samples were further taken for quantification of chlamydospore production in liquid media at 8 and 16 hours. Results: In normal control groups no fungus growth was found; however, potentially malignant and malignant cases showed fungus growth, positive germ tube test and chlamydospore formation. The result also showed rapid and quantitatively more chlamydospore formation in corn meal broth + 5% milk in comparison to serum milk culture media. Conclusion: The oral mucosa is compromised in potentially malignant lesions, it can be argued that this species may be involved in carcinogenesis by elaborating the nitrosamine compounds which either act directly on oral mucosa or interact with other chemical carcinogens to activate specific proto-oncogenes and thereby initiate oral neoplasia.

  2. Scytalidium parasiticum sp. nov., a New Species Parasitizing on Ganoderma boninense Isolated from Oil Palm in Peninsular Malaysia.

    Science.gov (United States)

    Goh, Yit Kheng; Goh, Teik Khiang; Marzuki, Nurul Fadhilah; Tung, Hun Jiat; Goh, You Keng; Goh, Kah Joo

    2015-06-01

    A mycoparasite, Scytalidium parasiticum sp. nov., isolated from the basidiomata of Ganoderma boninense causing basal stem rot of oil palm in Johor, Malaysia, is described and illustrated. It is distinct from other Scytalidium species in having smaller asci and ascospores (teleomorphic stage), longer arthroconidia (anamorphic stage), hyaline to yellowish chlamydospores, and producing a fluorescent pigment. The phylogenetic position of S. parasiticum was determined by sequence analyses of the internal transcribed spacers and the small-subunit ribosomal RNA gene regions. A key to identify Scytalidium species with teleomorphic stage is provided.

  3. Controle biológico de helmintos parasitos de animais: estágio atual e perspectivas futuras Biological control of helminth parasites of animals: current stage and future outlook

    Directory of Open Access Journals (Sweden)

    Marcelo de Andrade Mota

    2003-09-01

    Full Text Available O controle biológico é um método desenvolvido para diminuir uma população de parasitas pela utilização de antagonista natural. A administração de fungos nematófagos aos animais domésticos é considerada uma promissora alternativa na profilaxia das helmintíases gastrintestinais parasitárias. Os fungos nematófagos desenvolvem estruturas em forma de armadilhas, responsáveis pela captura e destruição dos estágios infectantes dos nematóides. Os fungos dos gêneros Arthrobotrys, Duddingtonia e Monacrosporium têm demonstrado eficácia em experimentos laboratoriais e no campo no controle de parasitos de bovinos, eqüinos, ovinos e suínos. Diversas formulações fúngicas têm sido avaliadas, no entanto, ainda não há nenhum produto comercial disponível. A associação dos grupos de pesquisa e o envolvimento das indústrias poderão colaborar para o sucesso na implementação desta forma de controle.Biological control is a non-chemical alternative method with its main goal to reduce the amount of parasite population using natural antagonists. The administration of nematophagous fungi to animals has been considered an alternative in gastrointestinal helminthiasis prophylaxis. The nematophagous fungi produce trap-shaped structures, which are responsible for capturing and destroying the free-living stages of nematodes. The genera Arthrobotrys, Duddingtonia and Monacrosporium has been shown efficacy in laboratory and field experiments against cattle, equine, ovine and swine parasites. Several fungi formulations have been evaluated, but there is so far no commercial product available. The association of research groups with industry could improve the successful implementation of this control method.

  4. Paleomycology of the Princeton Chert I. Fossil hyphomycetes associated with the early Eocene aquatic angiosperm, Eorhiza arnoldii.

    Science.gov (United States)

    Klymiuk, Ashley A; Taylor, Thomas N; Taylor, Edith L; Krings, Michael

    2013-01-01

    The Eocene (~ 48.7 Ma, Ypresian-Lutetian) Princeton Chert of British Columbia, Canada, has long been recognized as a significant paleobotanical locality, and a diverse assemblage of anatomically preserved fossil plants has been extensively documented. Co-occurring fossil fungi also have been observed, but the full scope of their diversity has yet to be comprehensively assessed. Here, we present the first of a series of investigations of fossilized fungi associated with the silicified plants of the Princeton Chert. This report focuses on saprotrophic, facultative-aquatic hyphomycetes observed in cortical aerenchyma tissue of an enigmatic angiosperm, Eorhiza arnoldii. Our use of paleontological thin sections provides the opportunity to observe and infer developmental features, making it possible to more accurately attribute two hyphomycetes that were observed in previous studies. These comprise multiseptate, holothallic, chlamydospore-like phragmoconidia most similar to extant Xylomyces giganteus and basipetal phragmospore-like chains of amerospores like those of extant Thielaviopsis basicola. We also describe a third hyphomycete that previously has not been recognized from this locality; biseptate, chlamydosporic phragmoconidia are distinguished by darkly melanized, inflated apical cells and are morphologically similar to Brachysporiella rhizoidea or Culcitalna achraspora.

  5. Production of gametangia by Phytophthora ramorum in vitro.

    Science.gov (United States)

    Brasier, Clive; Kirk, Susan

    2004-07-01

    Until now gametangia have not been obtained between paired European A1 and American A2 isolates of Phytopthora ramorum in vitro. Their production in artificial culture relies on interspecific pairings. Using P. drechsleri and P. cambivora testers, 51 of 110 P. ramorum isolates from across Europe were all shown to be A1s; while 32 of 38 American isolates from across California and southwest Oregon were shown to be A2s. However, these interspecific pairings are complex, unusually slow and unpredictable. A range of culture media and conditions are described that were tested, unsuccessfully, with a view to enhancing the efficiency of the interspecific pairings. In further tests, gametangia were obtained between A1 and A2 isolates of P. ramorum when juvenile, pre-chlamydospore producing mycelia were mixed together on carrot agar. The gametangia formed in 3-10 d, sparsely to frequently, initially only within the boundaries of the mixed inocula but subsequently in the extended mycelial growth. Chlamydospores were also produced. This inoculum-mixing method, though again sometimes unpredictable, should enhance efficiency of testing for compatibility types and facilitate further studies on whether the sexual outcrossing system of P. ramorum is functional. Differences between sexual reproduction of P. ramorum and that of other heterothallic Phytophthora species are discussed.

  6. Mutation of FVS1, encoding a protein with a sterile alpha motif domain, affects asexual reproduction in the fungal plant pathogen Fusarium oxysporum.

    Science.gov (United States)

    Iida, Yuichiro; Fujiwara, Kazuki; Yoshioka, Yosuke; Tsuge, Takashi

    2014-02-01

    Fusarium oxysporum produces three kinds of asexual spores: microconidia, macroconidia and chlamydospores. We previously analysed expressed sequence tags during vegetative growth and conidiation in F. oxysporum and found 42 genes that were markedly upregulated during conidiation compared to vegetative growth. One of the genes, FVS1, encodes a protein with a sterile alpha motif (SAM) domain, which functions in protein-protein interactions that are involved in transcriptional or post-transcriptional regulation and signal transduction. Here, we made FVS1-disrupted mutants from the melon wilt pathogen F. oxysporum f. sp. melonis. Although the mutants produced all three kinds of asexual spores with normal morphology, they formed markedly fewer microconidia and macroconidia than the wild type. The mutants appeared to have a defect in the development of the conidiogenesis cells, conidiophores and phialides, required for the formation of microconidia and macroconidia. In contrast, chlamydospore formation was dramatically promoted in the mutants. The growth rates of the mutants on media were slightly reduced, indicating that FVS1 is also involved in, but not essential for, vegetative growth. We also observed that mutation of FVS1 caused defects in conidial germination and virulence, suggesting that the Fvs1 has pleiotropic functions in F. oxysporum.

  7. The Contents of Ustiloxins A and B along with Their Distribution in Rice False Smut Balls

    Science.gov (United States)

    Wang, Xiaohan; Fu, Xiaoxiang; Lin, Fengke; Sun, Weibo; Meng, Jiajia; Wang, Ali; Lai, Daowan; Zhou, Ligang; Liu, Yang

    2016-01-01

    Ustiloxins are cyclopeptide mycotoxins isolated from rice false smut balls (FSBs), the ball-like colonies transformed from the individual grains through the filament infection by the fungal pathogen Villosiclava virens. There were no obvious relations between ustiloxin content and any of the collection areas, collection times, or average weight of each FSB. The rice false smut balls at early, middle, and late maturity stages were respectively divided into different parts (glume, chlamydospores, mycelia, and pseudoparenchyma). The highest content of ustiloxins A and B of rice FSBs was found at the early maturity stage. Both ustiloxins A and B were mainly distributed in the middle layer containing mycelia and immature chlamydospores of the FSBs. When the rice FSBs were at the early maturity stage, the total yield of ustiloxins A and B in the middle layer of each ball was 48.3 µg, which was 3.20-fold of the yield (15.1 µg) of the inner part of the ball. The rice FSBs at the early maturity stage are the appropriate materials for the production of ustiloxins A and B. PMID:27608042

  8. Pochonia chlamydosporia promotes the growth of tomato and lettuce plants

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    Rosangela Dallemole-Giaretta

    2015-10-01

    Full Text Available The fungus Pochonia chlamydosporia is one of the most studied biological agents used to control plant-parasitic nematodes. This study found that the isolates Pc-3, Pc-10 and Pc-19 of this fungus promote the growth of tomato and lettuce seedlings. The isolate Pc-19 colonized the rhizoplane of tomato seedlings in only 15 days and produced a large quantity of chlamydospores. This isolate was able to use cellulose as a carbon source, in addition to glucose and sucrose. Scanning electron microscopy (SEM revealed that hyphae of the P. chlamydosporia isolate Pc-10 penetrated the epidermal cells of the tomato roots. These three P. chlamydosporia isolates promote the growth of tomato and lettuce.

  9. [A case of Tinea capitis caused by Trichophyton tonsurans].

    Science.gov (United States)

    Urano, Shoko; Shirai, Shigeko; Suzuki, Yoko; Sugaya, Keiko; Takigawa, Masahiro; Mochizuki, Takashi

    2003-01-01

    A 10-year-old Peruvian girl, living in Japan since 1996, visited our hospital in August 2000 complaining of alopecia which had been present on her scalp for one year. The bald areas appeared as multiple small, scattered, angular patches with indistinct margins. Follicular pustules, erythemic nodules and lymphadenopathy were also seen. In the culture of the affected hair, a tan surface with wiry undulations grew on Sabouraud's media. The colony reverse had reddish-brown central pigmentation. Slide cultured fungi produced great numbers of round and short club-shaped microconidia, hyphae and intercalary chlamydospores. These fungi showed the following characteristics: positive urease test, no pigment production on cornmeal agar and positive thiamine dependency. The restriction fragment length polymorphism pattern and the nucleotide sequences of ribosomal-DNA internal transcribed spacer region of the causative fungus was compatible with Trichophyton tonsurans. Daily administration of 125 mg of terbinafine resulted in a satisfactory response and the lesion healed almost completely.

  10. Morphological and Molecular Characterization of Exophiala polymorpha sp. nov. Isolated from Sporotrichoid Lymphocutaneous Lesions in a Patient with Myasthenia Gravis.

    Science.gov (United States)

    Yong, Lee K; Wiederhold, Nathan P; Sutton, Deanna A; Sandoval-Denis, Marcelo; Lindner, Jonathan R; Fan, Hongxin; Sanders, Carmita; Guarro, Josep

    2015-09-01

    Exophiala species are capable of causing cutaneous and subcutaneous infections in immunocompromised patients. An Exophiala isolate was cultured from a biopsy specimen of a lesion on the forearm of a patient with myasthenia gravis. The patient also had lesions on the palm and distal aspects of the hand, which were successfully treated with a long-term course of itraconazole. A detailed morphological and molecular characterization of the isolate was undertaken. Phylogenetic analysis of the internal transcribed spacer region and portions of the β-tubulin and translation elongation factor 1-alpha genes indicated that the isolate was a novel species closely related to but genetically distinct from species within the Exophiala spinifera clade; the name Exophiala polymorpha sp. nov. is proposed. Morphologically, E. polymorpha most closely resembles E. xenobiotica but it differs in possessing phialides bearing prominent, wide collarettes, and it does not produce chlamydospores.

  11. Hichrom candida agar for identification of candida species

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    Baradkar V

    2010-01-01

    Full Text Available Chromogenic media are frequently used in direct and rapid identification of yeasts because different Candida species produce unique colors on these media. We used 60 isolates of Candida species including 30 C. albicans, 10 C. parapsilosis, 11 C. glabrata, five C. tropicalis, and four C. dubliniensis, isolated from various clinical specimens, to evaluate the performance of HiChrome Candida agar. These strains had been identified by germ tube test, morphology on cornmeal agar, chlamydospore formation on tobacco agar and sugar assimilation tests. The sensitivity and specificity results were: C. albicans (96.55 and 96.42%; C. parapsilosis (80 and 98.03%, C. glabrata (90.90 and 88.23%, C. tropicalis (100 and 100% and C. dubliniensis (60 and 96.55% respectively. HiChrom Candida agaris medium has been useful and capable of presumptive, rapid identification of Candida species within 48 hours.

  12. [A case of black dot ringworm on the right forearm caused by Trichophyton tonsurans].

    Science.gov (United States)

    Fujita, Shigeru; Mochizuki, Takashi

    2007-01-01

    We report a case of black dot ringworm on the right forearm caused by Trichophyton (T.) tonsurans. A 16-year-old male high school Judo-wrestler visited our clinic on September 30, 2005, complaining of a round erythematosquamous eruption with a distinct margin on the right forearm. Black dots were observed in the lesion. KOH-Parker ink prepared direct microscopy revealed abundant large endotrix arthroconidia in the hair shaft. Culture yielded yellowish-brown colonies. The isolate produced numerous round, short club-shaped microconidia along the hyphae unstained with lactophenol cotton blue (resembling matchsticks) and chlamydospores. PCR-RFLP analysis of internal transcribed spacer regions of ribosomal DNA revealed a banding pattern compatible with T. tonsurans. The lesion was cured by daily administration of 125 mg of terbinafine for 13 weeks.

  13. Isolation and characterization of a new fungal genus and species, Aphanoascella galapagosensis, from carapace keratitis of a Galapagos tortoise (Chelonoidis nigra microphyes).

    Science.gov (United States)

    Sutton, D A; Marín, Y; Thompson, E H; Wickes, B L; Fu, J; García, D; Swinford, A; de Maar, T; Guarro, J

    2013-02-01

    A new fungal genus and species, Aphanoascella galapagosensis, recovered from carapace keratitis in a Galapagos tortoise residing in a south Texas zoological collection, is characterized and described. The presence of a pale peridium composed of textura epidermoidea surrounded by scarce Hülle cell-like chlamydospores, and the characteristic reticulate ascospores with an equatorial rim separates it from other genera within the Onygenales. The phylogenetic tree inferred from the analysis of D1/D2 sequences demonstrates that this fungus represents a new lineage within that order. As D1/D2 and ITS sequence data also shows a further separation of Aphanoascus spp. into two monophyletic groups, we propose to retain the generic name Keratinophyton for species whose ascospores are pitted and display a conspicuous equatorial rim, and thereby propose new combinations in this genus for four Aphanoascus species.

  14. Biocontrol potential of Pasteuria penetrans, Pochonia chlamydosporia, Paecilomyces lilacinus and Trichoderma harzianum against Meloidogyne incognita in

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    Tariq MUKHTAR

    2013-05-01

    Full Text Available The root-knot nematode, Meloidogyne incognita, is a sedentary endoparasitic plant pathogen with a very wide host range, which causes annual crop losses amounting to millions of dollars. The small number of available nematicides and restrictions on the use of non-fumigant nematicides due to high toxicity to humans and non-target organisms hinder effective nematode control. A possible alternative to chemical nematicides is the use of biological control agents for the management of this nematode. In the present study, the efficacy of four biocontrol agents was tested against M. incognita at different doses. The biocontrol agents Pasteuria penetrans, Pochonia chlamydosporia, Paecilomyces lilacinus and Trichoderma harzianum were mass produced and mixed with the formalin sterilized soil at the rates of 2 × 103, 4 × 103, 6 × 103, 8 × 103, and 1 × 104 endospores/chlamydospores/cfu per g of soil. Okra seeds (cv. Sabz Pari were sown in pots of soil amended with the different agents, and 10 d after emergence, the plants were inoculated with 2000 freshly hatched second stage juveniles of M. incognita. Data on plant growth parameters and nematode infestations were recorded 7 weeks after inoculation. The antagonists varied significantly in enhancing various growth parameters and reducing nematode infestations in a dose-responsive manner. Both P. penetrans and P. lilacinus were equally effective and caused maximum reductions in number of galls, egg masses, nematode fecundity and build up as compared with T. harzianum and P. chlamydosporia. Reductions in these parameters at the concentration of 8 × 103 were statistically similar with those caused at the concentration of 1 × 104 chlamydospores/ endospores/cfu. Our results indicate that application of antagonists can suppress galling and reproduction of M. incognita resulting in enhancement of plant growth.

  15. Differentiation of Candida dubliniensis on chrom agar and Pal′s agar

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    Raut S

    2009-01-01

    Full Text Available Difference in expression of putative virulence factors and in antifungal susceptibility among different Candida species has raised the need for species-level identification. The close relationship of Candida dubliniensis with C. albicans has led to misidentification of C. dubliniensis isolates as C. albicans . Phenotypic tests include ability to produce chlamydospore on casein agar, colony colour development on differential media CHROM agar Candida medium and ability to form hyphal fringe on Pal′s agar, have been used to differentiate these two Candida species. Fifty isolates of Candida species were recovered from various specimens (blood, urine, tissue and respiratory secretions from diabetic and cancer patients between April and July 2007. The isolates were tested for chlamydospore production on casein agar. These were also streaked simultaneously on CHROM agar, Pal′s agar and a combination of CHROM agar supplemented with Pal′s agar for identification and differentiation of C. dubliniensis from C. albicans . On CHROM agar, 19 isolates were identified as C. dubliniensis , nine as C. albicans , 10 as C. krusei , nine as C. tropicalis and two as C. glabrata . One was indeterminate and later identified as C. dubliniensis . Out of the 20 C. dubliniensis isolates, 19 isolates exhibited hyphal fringe on Pal′s agar. On CHROM agar supplemented with Pal′s agar, 16 out of the 19 fringe-positive isolates exhibited fringe surrounding the bluish green-coloured colonies of C. dubliniensis . Additional identification tests like growth at 45oC and ability to reduce 2,3,5-triphenyltetrazolium chloride were time efficient, inexpensive and easy-to-use methods for differentiation of C. dubliniensis and C. albicans isolates. CHROM agar when supplemented with Pal′s agar gave definitive identification between C. dubliniensis and C. albicans .

  16. 稻曲病菌厚垣孢子脂肪酸组成的研究%Research on the composition of the fatty acids in chalmydospores of Ustilagioidea virens

    Institute of Scientific and Technical Information of China (English)

    任佐华; 毛莹; 虞选杰; 李媛; 刘二明

    2012-01-01

    [Objective] In order to investigate the relationship between the fatty acid composition and content and cell stress resistance in intracellular and cell wall. [Methods] In this study, three methods had been used for extracting the fatty acid from walls of chalmydospores, which were acid-heat method, soxhlet extraction and organic solvent, respectively. The fatty acid composition and content were detected by GC afterwards. [Results] Acid-heat extraction presented the best performance, by which the relative contents of saturated fatty acids in yellow, yellowish green and black chlamydospore walls were 26,92%, 17.23%, 23.71%, respectively, while unsaturated ones were 60.46%, 61.52%, 70.64%, separately. Further determination with the above same method, the relative total contents of 3 types of chlamydospores saturated fatty acids (precipitating wall plus supernatant) were 28.87%, 21.00%, 24.04%, separately and unsaturated ones with 55.43%, 55.87%, 63.89%, respectively. The content of stearic acid in saturated fatty acids in chlamydospore wall were yellow > yellowish green > black; the content of cis-5,8,11,14,17 eicosapentaenoic acid (EPA) methyl ester in unsaturated fatty acids in chlamydospore wall: black > yellowish green > yellow. [Conclusion] In all three colors of chlamydospore, either the total content of unsaturated fatty acids in spore or spore wall, the black showed the highest, which indicated that improving the content of unsaturated fatty acids in chlamydospores contributes to their dormancy and overwintering.%[目的]为探明细胞壁和细胞内脂肪酸成分及含量与细胞抗逆性的关系,[方法]采用酸热法、索氏提取法、有机溶剂法对稻曲病菌的厚垣孢子壁进行脂肪酸提取,并采用气相色谱检测其脂肪酸的组成和含量.[结果]采用酸热法提取脂肪酸效果最好,以该方法提取测定稻曲病菌黄色、黄绿色、黑色厚垣孢子壁饱和脂肪酸相对含量分别为26.92%、17.23

  17. Comparison among tomato juice agar with other three media for differentiation of Candida dubliniensis from Candida albicans Comparação do ágar suco de tomate com outros três meios, na diferenciação entre C. albicans e C. dubliniensis

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    Sydney Hartz Alves

    2006-06-01

    Full Text Available The purpose of the present study is to compare the tomato juice agar, a well known medium employed to observe ascospore formation, with niger seed agar, casein agar and sunflower seed agar, applied to a differentiation between C. dubliniensis and C. albicans. After 48 hours of incubation at 30 ºC all 26 (100% C. dubliniensis isolates tested produced chlamydospores on tomato juice agar as well as in the other three media evaluated. However, when we inoculated all media with C. albicans, the absence of chlamydospores became resulting in the following percents: tomato juice agar (92.47%, niger seed agar (96.7%, casein agar (91.39%, and sunflower seed agar (96.7%. These results indicate that tomato juice agar is another medium which can also be used in the first phenotypic differentiation between C. dubliniensis and C. albicans.O presente estudo teve como objetivo comparar o ágar suco de tomate, um tradicional meio utilizado para observação de ascósporos em leveduras, com o ágar semente de niger, ágar caseína e ágar semente de girassol, na diferenciação fenotípica entre C. albicans e C. dubliniensis. Após 48 h de incubação a 30 ºC, os 26 isolados de C. dublinienis (100% evidenciaram a formação de clamidoconídios igualmente em todos os meios comparados. Entretanto, quando semeados com C. albicans, a formação de clamidoconídios foi raramente observada, resultando nos seguintes percentuais de ausência destas estruturas: ágar suco de tomate (92,47%, ágar niger (96,7%, ágar caseína (91,39%, ágar semente de girassol (96,7%. Estes resultados permitem-nos sugerir a utilização do ágar suco de tomate como mais um meio que, já no primo-isolamento, é capaz de, presuntivamente, diferenciar C. albicans de C. dubliniensis.

  18. Predatory Capacity in vitro of Native Nematophagous Fungi from Cundinamarca on Gastrointestinal Nematodes of Cattle

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    Dildo Márquez Lara

    2015-12-01

    Full Text Available Dependence and indiscriminate use of chemical anthelmintics as the sole method for controlling gastrointestinal nematodes (GIN of cattle causes problems in the environment, public health, and the productivity of cattle. It is important to develop non-chemical control strategies. Nematophagous fungi can be a viable and promising alternative for the control of these endoparasites. This study aimed to isolate, identify and evaluate in vitro the potential of nematophagous fungi from Cundinamarca on L3 larvae of gastrointestinal nematodes of cattle. 60 soil samples from cattle ranches were sown in Petri boxes containing agar-water for trapping fungi, and three strains of the fungus Arthrobotrys oligospora (L1, XVIII, and XXI and one of Arthrobotrys musiformis (XXIV were identified by morphometric keys. 1 x 106 conidia or chlamydospores of each fungi were used, which faced 100 nematode larvae. Isolate XXIV (A. musiformis showed greater predatory capacity (96.8% than isolates (A. oligospora XVIII, L1, and XXI (69.68, 71.1, and 87.62%, respectively. There were no statistically significant differences (p > 0.05 among the strains with more predatory capacity. This is the first record of in vitro identification and evaluation of the predatory capacity of A. oligospora and A. musiformis, native fungi from Cundinamarca. The results suggest that these fungi could be used as biocontrol agents of nematodes in cattle.

  19. Two new hyaline-ascospored species of Trichoderma and their phylogenetic positions.

    Science.gov (United States)

    Qin, W T; Zhuang, W Y

    2016-01-01

    Collections of hypocrealean fungi found on decaying wood in subtropical regions of China were examined. Two new species, Trichoderma confluens and T. hubeiense, were discovered and are described. Trichoderma confluens is characterized by its widely effuse to rarely pulvinate, yellow stromata with densely disposed yellowish brown ostioles, simple acremonium- to verticillium-like conidiophores, hyaline conidia and multiform chlamydospores. Trichoderma hubeiense has pulvinate, grayish yellow stromata with brownish ostioles, trichoderma- to verticillium-like conidiophores and hyaline conidia. The phylogenetic positions of the two fungi were investigated based on sequence analyses of RNA polymerase II subunit b and translation elongation factor 1-α genes. The results indicate that T. confluens belongs to the Hypocreanum clade and is associated with but clearly separated from T. applanatum and T. decipiens. Trichoderma hubeiense belongs to the Polysporum clade and related to T. bavaricum but obviously differs from other members of the clade in sequence data. Morphological distinctions between the new species and their close relatives are noted and discussed.

  20. CULTURE DESCRIPTION OF SOME SPONTANEOUS LIGNICOLOUS MACROMYCETES SPECIES

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    BALAEŞ TIBERIUS

    2012-12-01

    Full Text Available 24 species of lignicolous macromycetes from 4 taxonomic families and 2 orders, Class Agaricomycetes, Phyllum Basidiomycota, have been analyzed. The cultural characters of these isolates had been observed, some of them being little studied till now. The dikaryotic mycelium from the trama of the sporoms was used for the isolation purpose. The fungal isolates were cultivated onto malt extract-agar media (malt extract 20g l-1 and incubated at 25 °C, in the dark, for 6 weeks. The cultures were observed directly and using a Nikon stereomicroscope in order to measure the growth rhythm and to observe the changes of the colonies: edge, surface, reverse, shape, colour, smell, presence or absence of the exudates. After 6 weeks from the inoculation, microscopic slides were made in order to investigate the types of hyphae, the colour and the structure of the mycelium and to note the presence of particular elements: cuticle, chlamydospors, arthrospores, conidia, and basidia. We noticed that the analyzed species present similar characters but also significant differences between them.

  1. Communities of endophytic sebacinales associated with roots of herbaceous plants in agricultural and grassland ecosystems are dominated by Serendipita herbamans sp. nov.

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    Kai Riess

    Full Text Available Endophytic fungi are known to be commonly associated with herbaceous plants, however, there are few studies focusing on their occurrence and distribution in plant roots from ecosystems with different land uses. To explore the phylogenetic diversity and community structure of Sebacinales endophytes from agricultural and grassland habitats under different land uses, we analysed the roots of herbaceous plants using strain isolation, polymerase chain reaction (PCR, transmission electron microscopy (TEM and co-cultivation experiments. A new sebacinoid strain named Serendipita herbamans belonging to Sebacinales group B was isolated from the roots of Bistorta vivipara, which is characterized by colourless monilioid cells (chlamydospores that become yellow with age. This species was very common and widely distributed in association with a broad spectrum of herbaceous plant families in diverse habitats, independent of land use type. Ultrastructurally, the presence of S. herbamans was detected in the cortical cells of Plantago media, Potentilla anserina and Triticum aestivum. In addition, 13 few frequent molecular operational taxonomic units (MOTUs or species were found across agricultural and grassland habitats, which did not exhibit a distinctive phylogenetic structure. Laboratory-based assays indicate that S. herbamans has the ability to colonize fine roots and stimulate plant growth. Although endophytic Sebacinales are widely distributed across agricultural and grassland habitats, TEM and nested PCR analyses reinforce the observation that these microorganisms are present in low quantity in plant roots, with no evidence of host specificity.

  2. Influence of ozone and HCl gas on citrus and the vesicular-arbuscular mycorrhizal fungus Glomus fasciculatus

    Energy Technology Data Exchange (ETDEWEB)

    McCool, P.M.; Menge, J.A.; Taylor, O.C.

    1977-01-01

    One half of Troyer citrange (Poncirus trifoliata x Citrus sinensis) seedlings were grown from seed and inoculated during transplanting with Glomus fasciculatus. Inoculum consisted of soil and roots from sudangrass (Sorghum vulgare) containing hyphae, vesicles, arbuscles, and chlamydospores of G. fasciculatus. At 5, 12, and 16 weeks after inoculation, both inoculated and noninoculated seedlings were exposed to 110-140 mg/m/sup 3/ (73-92 ppm) HCl gas for 20 minutes or to 2 mg/m/sup 3/ (1 ppm) ozone for 4 hours. HCl produced moderate marginal leaf necrosis while ozone produced no visible symptoms. Control and HCl-exposed mycorrhizal seedlings were 28% and 36% taller, respectively, than corresponding nonmycorrhizal seedlings. Exposure to HCl reduced mycorrhizal seedling height by 24% compared to mycorrhizal controls. Ozone exposed mycorrhizal citrus were not significantly taller than non-mycorrhizal citrus but were 37% shorter than mycorrhizal controls. Total biomass of control and HCl-exposed mycorrhizal seedlings were greater than their nonmycorrhizal counterparts but the biomass was not significantly different between ozone-exposed seedlings. Spore production by G. fasciculatus was reduced 50% in ozone-exposed seedlings while spore populations of HCl-exposed seedlings were not statistically different from the controls.

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

    Science.gov (United States)

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

    2017-04-01

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

  4. The rhizosphere microbial community in a multiple parallel mineralization system suppresses the pathogenic fungus Fusarium oxysporum.

    Science.gov (United States)

    Fujiwara, Kazuki; Iida, Yuichiro; Iwai, Takashi; Aoyama, Chihiro; Inukai, Ryuya; Ando, Akinori; Ogawa, Jun; Ohnishi, Jun; Terami, Fumihiro; Takano, Masao; Shinohara, Makoto

    2013-12-01

    The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum. © 2013 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  5. Rapid Culture Method of Aerobic Granule and Its Kinetics%好氧颗粒污泥的快速驯化及其动力学研究

    Institute of Scientific and Technical Information of China (English)

    于广丽; 李平; 王海磊

    2011-01-01

    报到了1种好氧颗粒污泥的快速驯化方法,通过向序批式反应器中投加Phanerochaete sp.HSD的厚垣孢子,在合成废水处理过程中,7d内便可成功驯化出好氧颗粒污泥.好氧颗粒污泥基质降解动力学参数Ks为757(mg·L-1),Vmax为1.1 h-1;生长动力学参数Y为0.177 kgMLVSS/COD,Kd为0.029 7 d-1.%In the present paper, a rapid culture method of aerobic granule is presented. By seeding the chlamydospores of Phanerochaete sp. HSD to sequencing batch reactor, aerobic granules are cultivated successfully in a week. In addition, kinetics of substrate degradation and biomass growth are discussed, and the results show that the kinetic coefficients of Ks, Vmax, Y and Kd are 757 mg/L, 1.1h-1,0. 177 kg · MLVSS/COD, 0. 029 7 d-1 , respectively.

  6. Arabidopsis thaliana model system reveals a continuum of responses to root endophyte colonization.

    Science.gov (United States)

    Mandyam, Keerthi G; Roe, Judith; Jumpponen, Ari

    2013-04-01

    We surveyed the non-mycorrhizal model plant Arabidopsis thaliana microscopically for its ability to form dark septate endophyte (DSE) symbioses in field, greenhouse, and laboratory studies. The laboratory studies were also used to estimate host growth responses to 34 Periconia macrospinosa and four Microdochium sp. isolates. Consistent with broad host range observed in previous experiments, field-, greenhouse-, and laboratory-grown A. thaliana were colonized by melanized inter- and intracellular hyphae and microsclerotia or chlamydospores indicative of DSE symbiosis. Host responses to colonization were variable and depended on the host ecotype. On average, two A. thaliana accessions (Col-0 and Cvi-0) responded negatively, whereas one (Kin-1) was unresponsive, a conclusion consistent with our previous analyses with forbs native to the field site where the fungi originate. Despite the average negative responses, examples of positive responses were also observed, a conclusion also congruent with earlier studies. Our results suggest that A. thaliana has potential as a model for more detailed dissection of the DSE symbiosis. Furthermore, our data suggest that host responses are controlled by variability in the host and endophyte genotypes.

  7. Isolation and morphological and metabolic characterization of common endophytes in annually burned tallgrass prairie.

    Science.gov (United States)

    Mandyam, Keerthi; Loughin, Thomas; Jumpponen, Ari

    2010-01-01

    Dark septate endophytes (DSE) are common and abundant root-colonizing fungi in the native tallgrass prairie. To characterize DSE fungi were isolated from roots of mixed tallgrass prairie plant communities. Isolates were grouped according to morphology, and the grouping was refined by ITS-RFLP and/or sequencing of the ITS region. Sporulating species of Periconia, Fusarium, Microdochium and Aspergillus were isolated along with many sterile fungi. Leek resynthesis was used to quickly screen for DSE fungi among the isolates. Periconia macro-spinosa and Microdochium sp. formed typical DSE structures in the roots; Periconia produced melanized intracellular microsclerotia in host root cortex, whereas Microdochium produced abundant melanized inter- and intracellular chlamydospores. To further validate the results of the leek resynthesis growth responses of leek and a dominant prairie grass, Andropogon gerardii, were assessed in a laboratory resynthesis system. Leek growth mainly was unresponsive to the inoculation with Periconia or Microdochium, whereas Andropogon tended to respond positively. Select Periconia and Microdochium isolates were tested further for their enzymatic capabilities and for ability to use organic and inorganic nitrogen sources. These fungi tested positive for amylase, cellulase, polyphenol oxidases and gelatinase. Periconia isolates used both organic and inorganic nitrogen sources. Our study identified distinct endophytes in a tallgrass prairie ecosystem and indicated that these endo-phytes can use a variety of complex nutrient sources, suggesting facultative biotrophic and saprotrophic habits.

  8. Identification and characterization of nine atypical Candida dubliniensis clinical isolates.

    Science.gov (United States)

    Albaina, Olatz; Sahand, Ismail H; Brusca, María I; Sullivan, Derek J; Fernández de Larrinoa, Iñigo; Moragues, María D

    2015-02-01

    Candida dubliniensis is a pathogenic yeast of the genus Candida closely related to Candida albicans. The phenotypic similarity of these two species often leads to misidentification of C. dubliniensis isolates in clinical samples. DNA-based methods continue to be the most effective means of discriminating accurately between the two species. Here, we report on the identification of nine unusual Candida isolates that showed ambiguous identification patterns on the basis of their phenotypic and immunological traits. The isolates were categorized into two groups. Group I isolates were unable to produce germ tubes and chlamydospores, and to agglutinate commercial latex particles coated with a mAb highly specific for C. dubliniensis. Group II isolates grew as pink and white colonies on CHROMagar Candida and ChromID Candida, respectively. Carbohydrate assimilation profiles obtained with API/ID32C together with PCR amplification with specific primers and DNA sequencing allowed reliable identification of the nine unusual clinical isolates as C. dubliniensis. © 2015 The Authors.

  9. RESPONSE OF TWO SUNFLOWER (HELIANTHUS ANNUUS L. GENOTYPES TO VA-MYCORRHIZAL INOCULATION AND PHOSPHORUS LEVELS

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    C.P. CHANDRASHEKARA, V.C. PATIL

    1995-01-01

    Full Text Available The performance of two sunflower genotypes (Morden and MSFH-8 with and without VA-mycorrhizal fungi at three P levels (38, 56 and 75 kg P2O5 ha-1 in vertisol of Dharwad was studied to determine the effect of mycorrhizal inoculation on plant growth, yield and P uptake. The results showed that the VAM inoculation increased sunflower yield (14%, total biomass (16%, oil content (3.1% and P uptake (30.5% over uninoculated control. The percent root colonization and chlamydo-spore count decreased with increasing P levels. The total biomass production, seed yield and P uptake of mycorrhizal plants at 38 kg P2O5 ha-1 more than the non-mycorrhizal plants at 75 kg P2O5 ha-1. The biomass and seed yield of mycorrhizal plants at same P level were more than the non-mycorrhizal plants. Mycorrhizal plants of Morden at 38 kg P2O5 ha-1 and MSFH-8 at 56 kg P2O5 ha-1 produced higher seed yield, oil content and total biomass than non-mycorrhizal plants supplied with 75 kg P2O5 ha-1. The results indicated that, VA-mycorrhizal inoculation helps in saving 25 and 50 percent of recommended dose of phosphatic fertilizer (75 kg P2O5 ha-1 in MSFH-8 (single cross hybrid and Morden (open pollinated variety, respectively.

  10. Ensaios de Mycologia Studies on Mycology

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    Octavio de Magalhães

    1928-01-01

    Full Text Available Morphologically the fungus reminds one of the Microsporum species of man. The microscopic elements are: the shape of the mycelia within the hairs, size and disposition of spores intercalar and terminal chlamydospores, simple clusters, hyphae, pectinate and denticulate elements. Of the 17 species of Microsporum described up to now, none can be identified with Microsporum circuluscentrum. The microsporum described is of the pure-by human type. (Culture fairly vivacious, almost total absence of spindles. Microscopically at first sight the culture might be taken for Microsporum fulvum URIBURU 1917 or for M. felineum. These are however from animals. The bean shaped culture on potatoes leaves a place apart for it among Microsporum fungi. The anomalous elements seen in the cultures are also found in other species of Microsporum. Besides the pseudo-perithecia described and interpreted I must mention that the pseudo-nodular organs are not an exception among these fungi, for Microsporum fulvum also shows what writers have described as nodular organs. The spiral elements are also not exclusive features of the trichophytes. Microsporum tardum also shows quite characteristic spiral forms.

  11. Clinical spectrum of exophiala infections and a novel Exophiala species, Exophiala hongkongensis.

    Science.gov (United States)

    Woo, Patrick C Y; Ngan, Antonio H Y; Tsang, Chris C C; Ling, Ian W H; Chan, Jasper F W; Leung, Shui-Yee; Yuen, Kwok-Yung; Lau, Susanna K P

    2013-01-01

    We characterized 12 Exophiala strains isolated from patients over a 15-year period to the species level using phenotypic tests and internal transcribed spacer (ITS) and Rpb1 sequencing and described the clinical spectrum of the 12 patients. Eight patients had nail or skin infections, two had invasive infections, and two had colonization of the gastrointestinal tract. ITS and Rpb1 sequencing showed that 11 of the 12 strains were known Exophiala species (E. oligosperma [n = 3], E. jeanselmei [n = 2], E. lecanii-corni [n = 2], E. bergeri [n = 1], E. cancerae [n = 1], E. dermatitidis [n = 1], and E. xenobiotica [n = 1]), which included the first reported cases of onychomycosis caused by E. bergeri and E. oligosperma. The 12th strain (HKU32(T)), isolated from the nail clipping of the right big toe of a 68-year-old female patient with onychomycosis, possessed unique morphological characteristics distinct from other Exophiala species. It grew very slowly and had a velvety colony texture after 28 days, short conidiophores of the same olivaceous color as the supporting hyphae, numerous spores, and no chlamydospore-like cells. ITS, Rpb1, β-tubulin, and β-actin gene sequencing unambiguously showed that HKU32(T) was clustered with but formed branches distinct from other Exophiala species in phylogenetic trees. We propose the new species Exophiala hongkongensis to describe this novel fungus.

  12. Issues in identifying germ tube positive yeasts by conventional methods.

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    Yazdanpanah, Atta; Khaithir, Tzar Mohd Nizam

    2014-01-01

    Candida speciation is vital for epidemiology and management of candidiasis. Nonmolecular conventional methods often fail to identify closely related germ tube positive yeasts from clinical specimens. The present study was conducted to identify these yeasts and to highlight issues in conventional versus molecular methods of identification. A total of 98 germ tube positive yeasts from high vaginal swabs were studied over a 12-month period. Isolates were examined with various methods including growth at 42 °C and 45 °C on Sabouraud dextrose agar (SDA), color development on CHROMagar Candida medium, chlamydospore production on corn meal agar at 25 °C, carbohydrate assimilation using ID 32C system, and polymerase chain reaction using a single pair of primers targeting the hyphal wall protein 1 (Hwp1) gene. Of all the isolates studied, 97 were molecularly confirmed as C. albicans and one isolate was identified as C. dubliniensis. No C. africana was detected in this study. The molecular method used in our study was an accurate and useful tool for discriminating C. albicans, C. dubliniensis, and C. africana. The conventional methods, however, were less accurate and riddled with many issues that will be discussed in further details.

  13. A high-temperature tolerant species in clade 9 of the genus Phytophthora: P. hydrogena sp. nov.

    Science.gov (United States)

    Yang, Xiao; Gallegly, Mannon E; Hong, Chuanxue

    2014-01-01

    A previously unknown Phytophthora species was isolated from irrigation water in Virginia, USA. This novel species produces abundant noncaducous and nonpapillate sporangia in soil water extract solution. It sometimes produces chlamydospores and hyphal swellings in aged cultures and in Petri's solution. This species has optimum vegetative growth at 30 C and grows well at 35 C. The lowest and highest temperatures for growth are 5 and 40 C. All isolates examined in this study are compatibility type A1 and produce mostly plerotic oospores when paired with an A2 mating-type tester of P. cinnamomi. Sequence analyses of the rDNA internal transcribed spacer (ITS) regions and the mitochondrially encoded cytochrome c oxidase 1 (cox 1) gene placed this species in clade 9 of the genus Phytophthora. These characteristics support the description of this taxon as a new species for which we propose the name P. hydrogena sp. nov. Further phylogenetic and physiological investigations of clade 9 species revealed a high-temperature tolerant cluster including P. hydrogena, P. aquimorbida, P. hydropathica, P. irrigata, P. chrysanthemi, P. insolita, P. polonica and P. parsiana. These species all grow well at 35 C. The monophyly of the species in this heat-tolerant cluster except P. insolita and P. polonica is highly supported by the maximum-likelihood analyses of the ITS and cox 1 sequences.

  14. Phytophthora ×stagnum nothosp. nov., a new hybrid from irrigation reservoirs at ornamental plant nurseries in Virginia.

    Science.gov (United States)

    Yang, Xiao; Richardson, Patricia A; Hong, Chuanxue

    2014-01-01

    A novel Phytophthora species was frequently recovered from irrigation reservoirs at several ornamental plant production facilities in eastern Virginia. Initial sequencing of the internal transcribed spacer (ITS) region of this species generated unreadable sequences due to continual polymorphic positions. Cloning and sequencing the ITS region as well as sequencing the mitochondrially encoded cytochrome c oxidase 1 and beta-tubulin genes revealed that it is a hybrid between P. taxon PgChlamydo as its paternal parent and an unknown species genetically close to P. mississippiae as its maternal parent. This hybrid has some diagnostic morphological features of P. taxon PgChlamydo and P. mississippiae. It produces catenulate hyphal swellings, characteristic of P. mississippiae, and chlamydospores, typical of P. taxon PgChlamydo. It also produces both ornamented and relatively smooth-walled oogonia. Ornamented oogonia are another important diagnostic character of P. mississippiae. The relatively smooth-walled oogonia may be indicative of oogonial character of P. taxon PgChlamydo. The new hybrid is described here as Phytophthora ×stagnum.

  15. Stromata, sporangiomata and chlamydosori of Phytophthora ramorum on inoculated Mediterranean woody plants.

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    Moralejo, Eduardo; Puig, Miquel; García, José A; Descals, Enrique

    2006-11-01

    Three types of multihyphal structures, stromata, sporangiomata and chlamydosori, are described for the plant pathogen Phytophthora ramorum. Their morphology, morphogenesis and position on the host organ were observed by dissecting, compound and scanning electron microscopy. Stromata were consistently formed one to two weeks after zoospore inoculation of detached leaves and fruits of an assortment of Mediterranean sclerophyll shrubs. Stroma initials appeared subcuticularly or subepidermally and developed as small hyphal aggregates by repeated branching, budding, swelling and interweaving, eventually forming a prosenchyma. They always emerged through the adaxial side of the leaf by rupture of the overlying host tissue. Occasionally sporangia and chlamydosori (packed clusters of chlamydospores) were formed on the stromata. Sporangiomata bore short sporangiophores and clusters of 20-100 sporangia and resembled sporodochia of the mitosporic fungi. The biological significance of these multihyphal structures is discussed. Some epidemiological aspects were also studied: several understorey species of the holm oak (Quercus ilex) woodland were susceptible to in vitro infection with three isolates of P. ramorum originally collected from different ornamental hosts. The risk of spread to this ecosystem is evaluated.

  16. Biocontrol of tomato plant diseases caused by Fusarium solani using a new isolated Aspergillus tubingensis CTM 507 glucose oxidase.

    Science.gov (United States)

    Kriaa, Mouna; Hammami, Inès; Sahnoun, Mouna; Azebou, Manel Cheffi; Triki, Mohamed Ali; Kammoun, Radhouane

    2015-10-01

    The present study focuses on the potential of glucose oxidase (GOD) as a promising biocontrol agent for fungal plant pathogens. In fact, a new GOD producing fungus was isolated and identified as an Aspergillus tubingensis. GOD (125 AU) has been found to inhibit Fusarium solani growth and spore production. Indeed, GOD caused the reduction of spores, the formation of chlamydospores, the induction of mycelial cords and the vacuolization of mycelium. In vivo assays, GOD acted as a curative treatment capable of protecting the tomato plants against F. solani diseases. In fact, the incidence was null in the curative treatment with GOD and it is around 45% for the preventive treatment. The optimization of media composition and culture conditions led to a 2.6-fold enhancement in enzyme activity, reaching 81.48U/mL. This study has demonstrated that GOD is a potent antifungal agent that could be used as a new biofungicide to protect plants from diseases. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  17. Melanization of Fusarium keratoplasticum (F. solani Species Complex) During Disseminated Fusariosis in a Patient with Acute Leukemia.

    Science.gov (United States)

    Chiewchanvit, Siri; Chongkae, Siriporn; Mahanupab, Pongsak; Nosanchuk, Joshua D; Pornsuwan, Soraya; Vanittanakom, Nongnuch; Youngchim, Sirida

    2017-06-14

    Fusarium spp. are recognized as the second most frequently filamentous fungi causing opportunistic infections and particularly important due to the increasing number of immunocompromised patients. F. keratoplasticum (a member of F. solani species complex) is one of the Fusarium species commonly associated with human infection, and therefore, studies on the virulence of this fungus are needed. This study aimed to confirm the presence of melanin in F. keratoplasticum from a patient with systemic fusariosis. Immunofluorescence labeling with anti-melanin monoclonal antibody (MAb) was used to examine an expression of melanin in F. keratoplasticum in vitro and during infection. Electron spin resonance identified the particles extracted from F. keratoplasticum as stable free radical consistent with melanin. Lesional skin from the sites with fusariosis contained hyphal structures that could be labeled by melanin-binding MAb, while digestion of the tissue yielded dark particles that were reactive. These findings suggest that F. keratoplasticum hyphae and chlamydospores can produce melanin in vitro and that hyphae can synthesize pigment in vivo. Given the potential role of melanin in virulence of other fungi, this pigment in F. keratoplasticum may play a role in the pathogenesis of fusariosis.

  18. Mapping of functional domains and characterization of the transcription factor Cph1 that mediate morphogenesis in Candida albicans.

    Science.gov (United States)

    Maiti, Protiti; Ghorai, Priyanka; Ghosh, Sumit; Kamthan, Mohan; Tyagi, Rakesh Kumar; Datta, Asis

    2015-10-01

    Cph1, a transcription factor of the Mitogen Activated Protein (MAP) kinase pathway, regulates morphogenesis in human fungal pathogen Candida albicans. Here, by following a systemic deletion approach, we have identified functional domains and motifs of Cph1 that are involved in transcription factor activity and cellular morphogenesis. We found that the N-terminal homeodomain is essential for the DNA binding activity; however, C-terminal domain and polyglutamine motif (PQ) are indispensable for the transcriptional activation function. Complementation analysis of the cph1Δ null mutant using various deletion derivatives revealed functional significance of the N- and C-terminal domains and PQ motif in filamentation process, chlamydospore formation and sensitivity to the cell wall interfering compounds. Genome-wide identification of the Cph1 binding site and quantitative RT-PCR transcript analysis in cph1Δ null mutant revealed that a number of genes which are associated with the filamentous growth, maintaining cell wall organization and mitochondrial function, and the genes of the pH response pathway are the transcriptional targets of Cph1. The data also suggest that Cph1 may function as a positive or negative regulator depending on the morphological state and physiological conditions. Moreover, differential expression of the upstream MAP kinase pathway genes in wild type and cph1Δ null mutant indicated the existence of a feedback regulation.

  19. A comparative study of carrier state of Candida and its speciation in oral flora – Among healthy individuals, persons with DM and HIV sero positive individuals

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    M. Bharathi

    2012-04-01

    Full Text Available The aim was to determine colonization rate of candida in oral cavity of healthy individuals, diabetics and HIV seropositive individuals.Material and methods: Samples were collected from oral cavity of 50 HIV sero positive individuals, 50 diabetics and 50 healthy individuals by swabbing palatal mucosa, dorsum of tongue and buccal mucosa with a sterile swab. Samples were processed by inoculating on Hi Chrome Agar and speciation was done by growth on Hi Chrome agar, germ tube test, chlamydospore formation on CMA, pellicle formation in SDA broth and growth at 45ºc.Results: 27 HIV sero positive individuals (54% carried candida in their oral cavities (single strain in 44% and combination of strains in 10%. Whereas it was 44% in diabetics (single species in 38% and a combination of species in 6% and 24% in healthy individuals (only single species. Candida albicans accounts for 41.66% in healthy individuals, 68% in diabetics and 42.42% in HIV seropositive persons. other species isolated were Candida tropicalis, Candida parapsilosis, Candida glabrata in all 3 groups in addition to Candida dubliniensis in healthy and HIV seropositive individuals and C.krusei in HIV seropositive persons only. P value- less than 0.05 between healthy persons & diabetics and between healthy persons & HIV seropositives (significant.Conclusion: candidal carriage was higher in diabetics and HIV seropositive individuals. Candida albicans was the commonest species in all three groups. Candida krusei was seen only in HIV positive persons.

  20. Fungal-Induced Deterioration of Mural Paintings: In Situ and Mock-Model Microscopy Analyses.

    Science.gov (United States)

    Unković, Nikola; Grbić, Milica Ljaljević; Stupar, Miloš; Savković, Željko; Jelikić, Aleksa; Stanojević, Dragan; Vukojević, Jelena

    2016-04-01

    Fungal deterioration of frescoes was studied in situ on a selected Serbian church, and on a laboratory model, utilizing standard and newly implemented microscopy techniques. Scanning electron microscopy (SEM) with energy-dispersive X-ray confirmed the limestone components of the plaster. Pigments used were identified as carbon black, green earth, iron oxide, ocher, and an ocher/cinnabar mixture. In situ microscopy, applied via a portable microscope ShuttlePix P-400R, proved very useful for detection of invisible micro-impairments and hidden, symptomless, microbial growth. SEM and optical microscopy established that observed deterioration symptoms, predominantly discoloration and pulverization of painted layers, were due to bacterial filaments and fungal hyphal penetration, and formation of a wide range of fungal structures (i.e., melanized hyphae, chlamydospores, microcolonial clusters, Cladosporium-like conidia, and Chaetomium perithecia and ascospores). The all year-round monitoring of spontaneous and induced fungal colonization of a "mock painting" in controlled laboratory conditions confirmed the decisive role of humidity level (70.18±6.91% RH) in efficient colonization of painted surfaces, as well as demonstrated increased bioreceptivity of painted surfaces to fungal colonization when plant-based adhesives (ilinocopie, murdent), compared with organic adhesives of animal origin (bone glue, egg white), are used for pigment sizing.

  1. The GRF10 homeobox gene regulates filamentous growth in the human fungal pathogen Candida albicans.

    Science.gov (United States)

    Ghosh, Anup K; Wangsanut, Tanaporn; Fonzi, William A; Rolfes, Ronda J

    2015-12-01

    Candida albicans is the most common human fungal pathogen and can cause life-threatening infections. Filamentous growth is critical in the pathogenicity of C. albicans, as the transition from yeast to hyphal forms is linked to virulence and is also a pivotal process in fungal biofilm development. Homeodomain-containing transcription factors have been linked to developmental processes in fungi and other eukaryotes. We report here on GRF10, a homeobox transcription factor-encoding gene that plays a role in C. albicans filamentation. Deletion of the GRF10 gene, in both C. albicans SN152 and BWP17 strain backgrounds, results in mutants with strongly decreased hyphal growth. The mutants are defective in chlamydospore and biofilm formation, as well as showing dramatically attenuated virulence in a mouse infection model. Expression of the GRF10 gene is highly induced during stationary phase and filamentation. In summary, our study emphasizes a new role for the homeodomain-containing transcription factor in morphogenesis and pathogenicity of C. albicans.

  2. Selection of potential antagonists against asparagus crown and root rot caused by Fusarium spp.

    Science.gov (United States)

    Rubio-Pérez, E; Molinero-Ruiz, M L; Melero-Vara, J M; Basallote-Ureba, M J

    2008-01-01

    Crown and root rot is one of the most important diseases of asparagus crop worldwide. Fusarium oxysporum f.sp. asparagi and F. proliferatum are the two species more frequently associated to this complex and their prevalence depends on the production area. The control of the disease on asparagus crop is difficult to achieve because its perennial condition and the long survival of the pathogen in the soil as chlamydospores or as mycelium in infected plant debris. Furthermore, Fusarium spp. are easily disseminated with asparagus propagation materials. Thus, control measures should aim at obtaining seedlings protection for longer than achieved with conventional pre-planting chemical treatments. The effectiveness of fungal antagonists on the control of diseases caused by soil borne fungi has been reported. The potential of Trichoderma spp. as a biological control agent against diseases caused by Fusarium spp. in tomato and asparagus has been studied . It has been suggested that microorganisms isolated from the root or rhizosphere of a specific crop may be better adapted to that crop and may provide better disease control than organisms originally isolated from other plant species. The objective of this work was the evaluation of the potential of fungal isolates from symptomless asparagus plants as biocontrol agents of Fusarium crown and root rot.

  3. Periglandula, a new fungal genus within the Clavicipitaceae and its association with Convolvulaceae.

    Science.gov (United States)

    Steiner, Ulrike; Leibner, Sarah; Schardl, Christopher Lewis; Leuchtmann, Adrian; Leistner, Eckhard

    2011-01-01

    We describe two newly discovered fungi living on the adaxial leaf surface of plants belonging to the Convolvulaceae, Ipomoea asarifolia and Turbina corymbosa. The fungi apparently are epibionts because hyphae were never observed to penetrate epidermal cells or stomata of their respective host plants, and most remarkably are intimately associated with secretory glands on the leaf surface. Hyphae and structures resembling chlamydospores and synnemata (but lacking conidia), formed by both fungal species are phenotypically nearly indistinguishable after in vitro growth or when examined in vivo on the leaf surface. Phylogenetic trees based on aligned DNA sequences from nuclear genes for β-tubulin (tubB) and RNA Polymerase II subunit 1 (rpbA), and the mitochondrial gene for ATP synthase F0 subunit A (atp6), grouped the fungal species in a clade within the Clavicipitaceae. Clavicipitaceous fungi isolated from the two different plant species could be distinguished by their atp6 and rpbA sequences, and nuclear genes for γ-actin (actG), translation elongation factor 1-α (tefA), and 4-(γ,γ-dimethylallyl)tryptophan synthase (dmaW), the determinant step in ergoline (i.e. ergot) alkaloid biosynthesis. Based on these findings we propose a new fungal genus, Periglandula, gen. nov., and describe two new species, Periglandula ipomoeae sp. nov., from host plant I. asarifolia, and Periglandula turbinae sp. nov., from T. corymbosa.

  4. In vitro: Response of plant growth regulators and antimalformins on conidia germination of Fusarium mangiferae and incidence of mango malformation.

    Science.gov (United States)

    Ansari, Mohammad Wahid; Tula, Suresh; Shukla, Alok; Pant, Ramesh Chandra; Tuteja, Narendra

    2013-11-01

    Mango malformation is the most important and threatening disease of recent times, primarily because of persistent lacuna in complete understanding of its nature. Diverse Fusarium spp, including F. mangiferae, were found to be associated with the disease. Here, F. mangiferae from mango cv Dashehri was morphologically characterized. Typically, oval-shaped microconidia without septum and crescent-shaped macroconidia with 3-septate were more often observed, whereas not a single chlamydospore was detected. The length and width of micro- and macro-conidia were 7.5, 55, 3.2, and 3.5, respectively. The plant growth regulators such as NAA, GA3, BAP and ethrel were found to induce in vitro germination of conidia of F. mangiferae after 12 h. In contrast, antimalformin silver nitrate (AgNO3) inhibits conidial germination in vitro and none of conidia was germinated beyond 500 ppm, however antimalformin glutathione was highly effective in stimulating conidial germination of F. mangiferae in vitro at > 1000 ppm after 24 h. We observed that the response of F. mangiferae to germinate the conidia in vitro under influence of plant growth regulators and antimalformins is not coincided with earlier findings of reduced disease incidence by exogenous application of these compounds. The present findings do not authenticate the involvement of F. mangiferae in the disease, however hormonal imbalance, most probably ethylene, might be responsible for deformed functional morphology of panicle. Further, a signal transduction mechanism of stress-stimulated ethylene imbalance causing physio-morphological changes in reproductive organs of mango flower and thereby failure of fertilization and fruit set, which needs to be investigated.

  5. SUSCEPTIBILITY OF CANDIDA SPECIES TO ANTIFUNGAL DRUGS IN WESTERN INDIA

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    Geeta M Vaghela

    2015-06-01

    Full Text Available Introduction: The increase in candidaemia is associated with high mortality. A shift has been observed in the relative frequency of each Candida spp. isolated from blood. Options of the antifungal drugs available for treatment of systemic and invasive candidiasis are restricted to polyenes, allylamines, azoles and recently developed echinocandin class of molecules. A rise in the incidence of antifungal resistance to Candida spp. has also been reported over the past decade. Studies on prevalence of infections and antifungal susceptibility testing are useful in deciding clinical strategies. Aims: To do species level identification and detect resistance, if any, among Indian clinical isolates of C. albicans. Methodology: From total 135 patients from a tertiary care hospital of Gujarat, Candida species were isolated from different clinical specimens. The growth of Candida on Sabouraud's dextrose agar was confirmed by Gram staining in which gram positive budding fungal cells were observed. Then its growth was examined for colony morphology on Sabouraud's dextrose agar and chlamydospore production on Corn meal tween 80 agar. Germ tube tests and other biochemical tests like sugar fermentation, sugar assimilation and urease test were performed to identify the species of Candida. Antifungal susceptibility testing was performed by NCCLS M44-A Disc diffusion method. Results: Out of total 135 samples, C. Albicans were isolated from 52 (38.5%. Among Non Albican Candid (NAC, Candida glabrata was 36 (26.7% followed by Candida tropicalis 25(18.5%. C. albicans was found resistant to Fluconazole, Itraconazole and Amphotericine B in 3.8%, 3.8% and 1.9% cases respectively. For NAC, resistance of Fluconazole, Itraconazole and Amphotericine B was found in 4.8%, 3.6% and 2.4% cases respectively. [Natl J Med Res 2015; 5(2.000: 122-126

  6. CONTROL OF SOIL-BORNE DISEASES BY DIFFERENT COMPOSTS IN POTTED VEGETABLE CROPS.

    Science.gov (United States)

    Pugliese, M; Benetti, A; Gilardi, G; Gullino, M L; Garibaldi, A

    2014-01-01

    The composting process and the type and nature of wastes and raw materials influence the maturity, quality and suppressiveness of composts. Variability in disease suppression also depends on the pathosystem, on soil or substrate type, on chemical-physical conditions, like pH and moisture, and on the microbial component of compost. The aim of the research was to evaluate the suppressiveness of composts, originated from green wastes and/or municipal biowastes, and produced by different composting plants located in Europe. The composts were tested against soil-borne pathogens in greenhouse on potted plants: Fusarium oxysporum f.sp. busilici/basil, Pythium ultimum/cucumber, Rhizoctonia solani/bean. Composts were blended with a peat substrate at different dosages (10, 20 and 50% vol./vol.) 14 days before seeding or transplanting. Pythium ultimum and Rhizoctonia solani were mixed into the substrate at 0.5 g of wheat kernels L(-1) 7 days before seeding, while, in the case of Fusarium oxysporum f.sp. basilici, chlamydospores were applied at 1 x 10(4) CFU/g. Seeds of basil, cucumber and bean were sown into 2 L pots in greenhouse. The number of alive plants was counted and above ground biomass was weighed 30 days after seeding. The number of infected cucumber and basil plants was significantly reduced by increasing dosages of composts, but municipal compost was phytotoxic when applied at high dosages compared to green compost. Moreover, municipal compost increased the disease caused by Rhizoctonia solani on bean. The use of compost in substrates can be a suitable strategy for controlling soil-borne diseases on vegetable crops, but results depend on type of composts, application rates and pathosystems.

  7. The genera of Hyphomycetes - 2011 update.

    Science.gov (United States)

    Seifert, K A; Gams, W

    2011-12-01

    This supplement to the taxonomic monograph The Genera of Hyphomycetes summarises information on 23 accepted new genera and c. 160 species described in 2011. These include three dematiaceous genera (Funbolia, Noosia, Pyrigemmula, all related to Dothideomycetes), a bulbil-producing genus, Spiroplana (Pleosporales), and two endophytic genera, the sterile Periglandula (Clavicipitaceae), and the hyaline, sympodial Micronematobotrys (Pyronemataceae). Slow-growing, morphologically-reduced, darkly pigmented fungi continue to be the source of new taxa, including the new genus Atramixtia (Dothioraceae). Eight new genera of darkly pigmented chlamydospore-like anamorphs were described from marine or subtidal environments (Glomerulispora, Halozoön, Hiogispora, Matsusporium, Moheitospora, Moleospora, Moromyces), mostly associated with subclades of the Lulworthiales. Several genera that are morphologically similar to but phylogenetically distinct from genera of the Capnodiales (Pseudopassalora, Scleroramularia) were introduced, as well as segregates from the classical concepts of Alternaria (Sinomyces), Chalara and Phialophora (Brachyalara, Infundichalara, Lasiadelphia), and Paecilomyces (Purpureocillium for the former Paecilomyces lilacinus complex). In addition, in anticipation of the new nomenclatural rules, newly configured formerly-teleomorph genera were proposed as segregates from classical hyphomycete genera in the Hypocreales, namely Acremonium (Cosmospora), Fusarium (Cyanonectria, Dialonectria, Geejayessia, Macroconia, Stylonectria), and Volutella (Pseudonectria) and the Trichocomaceae, Eurotiales, Penicillium (Talaromyces for the former Penicillium subg. Biverticillium). Standardized generic mini-diagnoses are provided for the accepted new genera, along with details of distribution, substrates, numbers of new species and phylogenetic affinities within the Dikarya. GenBank accession numbers for ITS DNA-barcodes are provided where available. New information on generic

  8. Septate endophyte colonization and host responses of grasses and forbs native to a tallgrass prairie.

    Science.gov (United States)

    Mandyam, Keerthi; Fox, Chad; Jumpponen, Ari

    2012-02-01

    Native tallgrass prairies support distinct dark septate endophyte (DSE) communities exemplified by Periconia macrospinosa and Microdochium sp. that were recently identified as common root symbionts in this system. Since these DSE fungi were repeatedly isolated from grasses and forbs, we aimed to test their abilities to colonize different hosts. One Microdochium and three Periconia strains were screened for colonization and growth responses using five native grasses and six forbs in an in vitro system. Previously published data for an additional grass (Andropogon gerardii) were included and reanalyzed. Presence of indicative inter- and intracellular structures (melanized hyphae, microsclerotia, and chlamydospores) demonstrated that all plant species were colonized by the DSE isolates albeit to varying degrees. Microscopic observations suggested that, compared to forbs, grasses were colonized to a greater degree in vitro. Host biomass responses varied among the host species. In broad comparisons, more grass species than forbs tended to respond positively to colonization, whereas more forb species tended to be non-responsive. Based on the suspected differences in the levels of colonization, we predicted that tallgrass prairie grasses would support greater DSE colonization than forbs in the field. A survey of field-collected roots from 15 native species supported this hypothesis. Our study supports the "broad host range" of DSE fungi, although the differences in the rates of colonization in the laboratory and in the field suggest a greater compatibility between grasses and DSE fungi. Furthermore, host responses to DSE range from mutualism to parasitism, suggesting a genotype-level interplay between the fungi and their hosts that determines the outcome of this symbiosis.

  9. Molecular Identification of Candida Albicans Isolated From the Oncology Patients at Four University Hospitals in Mazandaran Province (2005-6

    Directory of Open Access Journals (Sweden)

    H. Karami, M.D.

    2007-01-01

    Full Text Available AbstractBackground and Purpose: Early detection of Candida species in body site could improve the survival of the immunosuppressed patients by allowing the initiation of specific treatment while the fungal biomass is still low. The aim of this study was the identification of Candida albicans isolated from the oncology patients by molecular methods.Materials and Methods: Sixty two of Candida albicans isolated identified by phenotypic methods (color of colony on CHROMagar medium, germ-tube formation in horse serum, chlamydospore formation on Cornmeal agar with 1% Tween 80. DNA was extracted by using a glass bead/phenol- chloroform method. The oligonucleotide primer pairs (NL1/NL4 were used to amplify a 620-bp fragment of D1/D2 region of large submit (26s ribosomal DNA gene. PCR-products were electrophoresed in a 1.5% agarose gel. Eighteen PCR-amplified products sequenced and results were evaluated by online BLAST software. Multiple sequence alignment was performed by using online CLUSTAL-W (version 1.83 software.Results: The BLAST search revealed that all of products were Candida albicans. All sequences showed >99% similarity when compared with known reference sequences at the Gene-Bank. Four different strains were obtained of albicans species, including: AA 1622b (13 samples, 24698 (3 samples, TA 62 (1samples and 551 FC (1 sample. A total of 131 nucleotide exchange sites were revealed.Conclusion: The dominant species by phenotypic approaches was Candida albicans. In addition, identification of Candida albicans by (26S rDNA sequencing was 100% concordant to the results obtained by the phenotypic metho

  10. Analysis the Inspection Process ofCandida albicans in Food%食品中白色念珠菌的检测工艺

    Institute of Scientific and Technical Information of China (English)

    王愚; 李甜甜

    2016-01-01

    Candida albicans is a common fungal pathogen, which shows a big difference in colony characteristics with the other yeast when using different culture medium to culture. On the chromogenic strains ofCandida albicans is blue-green, and can produce chlamydospore and germ tubes, what more important is that it can produce acid and gas in glucose and maltose fermentation test, however there is only acid acid fermentation test in sucrose yield. Experimental data shows that put 10 albicans into 100 microliters of sample,Candida albicans can be detected by chromogenic medium.%白色念珠菌是一种常见的真菌病原体,用不同的培养基对白色念珠菌进行培养时,它所展现的菌落特征与其他酵母存在很大差别。在显色培养基上白色念珠菌菌株呈蓝绿色,并且能够产生后垣孢子与芽管,在葡萄糖与麦芽糖发酵试验中能产酸产气,在蔗糖发酵试验中只产酸不产气。实验数据表明,将10个左右的白色念珠菌放入到100μL样品中,白色念珠菌能够被显色培养基检测出来。

  11. Chitosan Increases Tomato Root Colonization by Pochonia chlamydosporia and Their Combination Reduces Root-Knot Nematode Damage

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    Nuria Escudero

    2017-09-01

    Full Text Available The use of biological control agents could be a non-chemical alternative for management of Meloidogyne spp. [root-knot nematodes (RKN], the most damaging plant-parasitic nematodes for horticultural crops worldwide. Pochonia chlamydosporia is a fungal parasite of RKN eggs that can colonize endophytically roots of several cultivated plant species, but in field applications the fungus shows a low persistence and efficiency in RKN management. The combined use of P. chlamydosporia with an enhancer could help its ability to develop in soil and colonize roots, thereby increasing its efficiency against nematodes. Previous work has shown that chitosan enhances P. chlamydosporia sporulation and production of extracellular enzymes, as well as nematode egg parasitism in laboratory bioassays. This work shows that chitosan at low concentrations (up to 0.1 mg ml-1 do not affect the viability and germination of P. chlamydosporia chlamydospores and improves mycelial growth respect to treatments without chitosan. Tomato plants irrigated with chitosan (same dose limit increased root weight and length after 30 days. Chitosan irrigation increased dry shoot and fresh root weight of tomato plants inoculated with Meloidogyne javanica, root length when they were inoculated with P. chlamydosporia, and dry shoot weight of plants inoculated with both P. chlamydosporia and M. javanica. Chitosan irrigation significantly enhanced root colonization by P. chlamydosporia, but neither nematode infection per plant nor fungal egg parasitism was affected. Tomato plants cultivated in a mid-suppressive (29.3 ± 4.7% RKN egg infection non-sterilized clay loam soil and irrigated with chitosan had enhanced shoot growth, reduced RKN multiplication, and disease severity. Chitosan irrigation in a highly suppressive (73.7 ± 2.6% RKN egg infection sterilized-sandy loam soil reduced RKN multiplication in tomato. However, chitosan did not affect disease severity or plant growth irrespective of

  12. Prevalance and risk factors for yeast colonization in adult diabetic patients.

    Science.gov (United States)

    Sahin, Idris; Oksuz, Sukru; Sencan, Irfan; Gulcan, Aynur; Karabay, Oguz; Gulcan, Erim; Yildiz, Ozcan

    2005-04-01

    The aim of this study is to describe the associations between various host characteristics and yeast colonization; biofilm and phospholipase production in diabetic patients. The study was conducted between January 2003 and June 2003 in Abant Izzet Baysal University, Duzce, Turkey. One hundred and fourty five diabetic patients were included to the study. All oral and faecal specimens were placed on Sabourand dextrose agar with chloramphenicol and gentamicin. All isolates were identified with classic methods and carbohydrate assimilation patterns using API 20 CAUX. C. dubliniensis isolates were identified by CHROM agar Candida and chlamydospore formation according to the referral to the literature. Biofilm and phospholipase production was assessed by using previously described methods. The most common colonized species were C. albicans in oral and faecal cultures. C. dubliniensis was isolated in four oral cultures of the patients. Dental prosthesis, tooth brushing, older age, antibiotic use in the previous two weeks were found to be the significant factors for the oral yeast colonization. Younger age, smoking, shorter duration of diabetes, hospitalization in the last year and antibiotic use in the previous two weeks were found to be the significant factors for the faecal yeast colonization. Biofilm production was found to be positive in nine cases of oral and seven of faecal isolates. Phospholipase production was determined to be positive in 18 cases oral and 14 of faecal isolates. In conclusion, glycaemia control and other diabetic factors are not effective for yeast colonlizing. There was not any significant correlation between biofilm and phospholipase production and host characteristics in yeast colonization. Oral hygiene may be an effetive for decreasing the oral colonization in diabetic patients.

  13. Fusarium foetens, a new species pathogenic to begonia elatior hybrids (Begonia x hiemalis) and the sister taxon of the Fusarium oxysporum species complex.

    Science.gov (United States)

    Schroers, H-J; Baayen, R P; Meffert, J P; de Gruyter, J; Hooftman, M; O'Donnell, K

    2004-01-01

    A new disease recently was discovered in begonia elatior hybrid (Begonia × hiemalis) nurseries in The Netherlands. Diseased plants showed a combination of basal rot, vein yellowing and wilting and the base of collapsing plants was covered by unusually large masses of Fusarium macroconidia. A species of Fusarium was isolated consistently from the discolored veins of leaves and stems. It differed morphologically from F. begoniae, a known agent of begonia flower, leaf and stem blight. The Fusarium species resembled members of the F. oxysporum species complex in producing short monophialides on the aerial mycelium and abundant chlamydospores. Other phenotypic characters such as polyphialides formed occasionally in at least some strains, relatively long monophialides intermingled with the short monophialides formed on the aerial mycelium, distinct sporodochial conidiomata, and distinct pungent colony odor distinguished it from the F. oxysporum species complex. Phylogenetic analyses of partial sequences of the mitochondrial small subunit of the ribosomal DNA (mtSSU rDNA), nuclear translation elongation factor 1α (EF-1α) and β-tubulin gene exons and introns indicate that the Fusarium species represents a sister group of the F. oxysporum species complex. Begonia × hiemalis cultivars Bazan, Bellona and Netja Dark proved to be highly susceptible to the new species. Inoculated plants developed tracheomycosis within 4 wk, and most died within 8 wk. The new taxon was not pathogenic to Euphorbia pulcherrima, Impatiens walleriana and Saintpaulia ionantha that commonly are grown in nurseries along with B. × hiemalis. Inoculated plants of Cyclamen persicum did not develop the disease but had discolored vessels from which the inoculated fungus was isolated. Given that the newly discovered begonia pathogen is distinct in pathogenicity, morphology and phylogeny from other fusaria, it is described here as a new species, Fusarium foetens.

  14. IDENTIFICATION OF CANDIDA SPECIES FROM CLINICAL SAMPLES AND THEIR ANTIFUNGAL SUSCEPTIBILITY PATTERNS

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    Bhaskar

    2015-09-01

    Full Text Available OBJECTIVE AND BACKGROUND : The incidence of Candida infections has increased dramatically over the past few decades due to increase in the number of population susceptible to fungal infections. With multiple antifungal ag ents that are available and recovery of clinical isolates that exhibit inherent or developed resistance to commonly used antifungal agents, it has become imperative to do susceptibility testing routinely. The study was done to determine the predisposing fa ctors, species incidence and susceptibility pattern of Candida isolates to commonly use d antifungal agents. METHODS: A total of 108 Candida species were recovered from symptomatic clinical cases. Candida isolates were speciated by germ tube test, chlamydospore formation on corn meal agar and color produced on chromogenic media. Antifungal susceptibility test was done by disk diffusion method for nystatin, fluconazole, itraconazole, voriconazole and amphotericin - B. RESULTS: Candida albicans is the m ost frequently isolated species. However, non - albicans Candida species, taken as a group has predominated in clinical samples. Chromogenic agar medium showed good correlation in species identification in comparison with conventional germ tube test and chla mydospore formation on corn meal agar. C. albicans (41, C. tropicalis (33, C. krusei (30 and C. glabrata (04 were isolated. Candida species showed 95.4% susceptibility to amphotericin - B, 77.8% to voriconazol e, 69.4% to nystatin, 64.1% to f luconazole an d 63.9% to itraconazole. CONCLUSION : Increasing incidence of non - albicans species infection. Chromogenic medium can be used for species identification. Increasing resistance of Candida species to commonly used antifungal agents.

  15. [Candida dubliniensis studies and isolation of Candida types in oropharyngeal specimens from oncologic patients].

    Science.gov (United States)

    Tekeli, Alper; Dolapçi, Iştar; Cesur, Salih; Tekeli, Emin; Içli, Fikri

    2002-01-01

    Fungal opportunistic infections, and in particular those caused by the various Candida species, have gained considerable significance as a cause of morbidity and, often, mortality. Although Candida albicans remains to be the most frequently isolated fungal species as an opportunistic oral pathogen, other yeast species are often identified in immunocompromised patients. C. dubliniensis, the recently described species, has been recovered primarily from oropharyngeal candidasis in Human Immunodeficiency Virus (HIV)-infected patients. C. dubliniensis shares many phenotypic characteristics with, and is phylogenetically closely related to, C. albicans. The aim of the present study was to investigate the colonization rates of fungal species, and especially C. dubliniensis, in the oropharyngeal samples from cancer patients. The oropharyngeal swabs of 543 patients were collected during their visits to oncology clinic in 9 months period, and a total of 209 Candida species have been isolated. Of them, 147 isolates were found to be positive for germ tube and chlamydospore formation, and they were tested for the growth inability at 42 degrees C and 45 degrees C, colony morphology in Staib agar and the intracellular beta-glucosidase activity, in order to identify C. dubliniensis. The results of these tests and carbohydrate assimilation tests by API 20C AUX yeast identification system, yielded that all these 147 (70.3%) isolates were C. albicans. The other isolates were identified as follows; 16 C. parapsilosis (7.6%), 13 C. tropicalis (6.2%), 10 C. glabrata (4.7%), 5 C. guilliermondii (2.3%), 4 C. krusei (1.9%), 3 C. keyfr (1.4%), 3 C. famata (1.4%), 2 S. cerevisiae (0.9%), 2 C. pelliculosa (0.9%), 1 C. utiles (0.4%), 1 C. neoformans (0.4%) and 1 Hansenula polymorpha (0.4%), while no C. dubliniensis was isolated.

  16. First-time isolation of Candida dubliniensis from plaque and carious dentine of primary teeth.

    Science.gov (United States)

    Kneist, S; Borutta, A; Sigusch, B W; Nietzsche, S; Küpper, H; Kostrzewa, M; Callaway, A

    2015-08-01

    To determine those organisms of the genus Candida associated with dental caries by investigating samples from active carious lesions. Within the genus Candida, the species Candida albicans and Candida dubliniensis are capable of forming chlamydospores and germ tubes. Until it became possible in 1995 to differentiate between the two species taxonomically, C. dubliniensis was falsely identified as C. albicans. Whilst the importance of C. albicans for rapidly progressing early childhood caries (ECC) has been recognised, so far there have been only reports about C. dubliniensis in connection with children/mothers who have been infected with HIV or already developed AIDS. In the present study, C. dubliniensis was for the first time isolated from plaque and carious dentine of a healthy five-year-old boy. As part of the investigation, a number of samples were collected from individual children affected by active dental caries. Amongst the samples, one in particular indicated that Candida species might be involved. The patient was a five-year-old boy with ECC of the primary dentition, scheduled for restorative treatment under general anaesthesia. Before treatment, a salivary, plaque (region of 54/55) and soft carious dentine sample from the tooth 51 was taken before extraction. The counts of yeasts, lactobacilli (LB) and mutans streptococci were determined in the samples. The boy's dmft was 11, which was dominated by the d component. In the saliva of the boy, LB and mutans streptococci (MS) were detected. In plaque and carious dentine, MS and most interestingly C. dubliniensis were present. The yeasts were visualised in carious dentine by means of scanning electron micrographs. Plaque and carious dentine may be a further habitat of C. dubliniensis.

  17. Fungicidal activity of Eucalyptus tereticornis essential oil on the pathogenic fungus Fusarium oxysporum Actividad antimicótica del aceite esencial a partir de Eucalyptus tereticornis sobre el hongo patógeno Fusarium oxysporum

    Directory of Open Access Journals (Sweden)

    Walter Murillo Arango

    2011-06-01

    Full Text Available The objective of present paper was to determine the antifungal activity of the Eucalyptus tereticornis (Myrtaceae essential oil and two fractions on the Fusarium oxysporum mushroom, a pathogen with clinical and agricultural significance. The total citronelal (44.8 % and geraniol (9.78 % essential oil had a fungicidal effect at a 3 g/L concentration and a fungicidal activity at small concentrations. The A and B fractions composed most of p-mentane-3,8-diol (18.95 % and geraniol acetate (24.34 %, respectively were more active than the total extract. The observations at microscopic level showed damages and changes in hyphae and chlamydospores, as well as a decrease in the number of conidia. The observed fungicidal activity and the morphologic damages were dependent on the concentration.El objetivo de este trabajo fue determinar la actividad antifúngica del aceite esencial de Eucalyptus tereticornis (Myrtaceae y 2 fracciones sobre el hongo Fusarium oxysporum, patógeno de importancia tanto clínica como agrícola. El aceite esencial total, compuesto principalmente por citronelal (44,8 %, citronelol (9,78 % presentó un efecto fungicida a una concentración de 3 g/L y actividad fungistática a concentraciones menores. La fracciones A y B compuestas en su mayoría por p-mentano-3,8-diol (18,95 % y acetato de citronelol (24,34 % respectivamente fueron más activas que el extracto total. Las observaciones a nivel microscópico mostraron daños y cambios en hifas y clamidosporas, así como disminución en el número de conidias. La actividad fungistática observada y los daños morfológicos fueron dependientes de la concentración.

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

    Science.gov (United States)

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

    2005-01-01

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

  19. 山东烟区土壤VA菌根真菌的分离鉴定%Isolation and Identification of Vesicular Arbuscular Mycorrhizal Fungi in Tobacco Culture Area in Shandong Province

    Institute of Scientific and Technical Information of China (English)

    刘延荣; 方宇澄; 黄镇

    2001-01-01

    从山东烟区的不同类型的植烟土壤中,采集烟草根际土,经湿筛倾倒蔗糖浮选分离VA菌根真菌孢子,单孢接种烟苗在水培条件下,选出在烟草上能形成VA菌根的菌株进行分类研究。鉴定出烟草VA菌根真菌2个属11个种。属于球囊霉属Glomus的种:苏格兰球囊霉G.cale donium( Nicol.& Gerd.)Gerd.& Trappe,近明球囊霉 G.claroideum Schenck & Smith,缩球囊霉 G .constrictum Trappe,德里球囊霉 G.delhiense Mukerji, Bhattacharjee & T ewari,透光球囊霉 G.diaphanum Morton & Walker,幼套球囊霉 G.etunicatum Becker & Gerdmann, 聚集球囊霉G.glomerulatum Sieverding, 根内球囊霉G.intraradices Schenck & Smith,摩西球囊霉 G.mosseae (Nicol. & Gerd.) Gerd. & Trappe, 网状球囊霉G.retic ulatum Bhatta charjee & Mukerji;属于无梗孢囊霉属 Acaulospora的种:詹氏无梗孢囊霉 A.ger demanni i Schenck & Nicolson。其中德里球囊霉、聚集球囊霉、网状球囊霉和詹氏无梗孢囊霉4 个种为我国新纪录种。对各个种的形态特征进行了详细描述。%Chlamydospores and azygospores of vesicular arbuscular mycorr hizal fungi(VAMF) were isolated by wet sieving and decanting method from rhizosp herical soils of tobacco. Tobacco seedlings at four leaf stage were inoculated w ith single spores of fungal isolates and transferred into sterilized sand in bla ck plastic tubes and then cultured in solution with low level of nutrients. VAM on tobacco were reisolated and 11 species in 2 genera were indentified, includin g G. caledoniu, G.claroideum, G.constrictum, G.delhiense, G.diaphanum, G .etunicatum, G.glomerulatum, G.intraradices, G.mosseae and G.reticulat um i n genus Glomus, and A.gerdemannii in genus Acaulospora. Of which, G .delhiense ,G.glome-rulatum, G.reticulatum and A.gerdemannii were first recorded in China.

  20. [Epidemiology of otomycoses at the University Hospital of Yopougon (Abidjan-Ivory Coast)].

    Science.gov (United States)

    Adoubryn, K D; N'Gattia, V K; Kouadio-Yapo, G C; Nigué, L; Zika, D K; Ouhon, J

    2014-06-01

    Otomycosis is a fungal infection, which leads to a damage of the external auditory meatus. The disease is worldwide in distribution but is said to be more common in tropical countries. Though otomycosis presumably occurs frequently in Africa, reports on its incidence and etiology are rare from Côte d'Ivoire. The objective of this study was to evaluate the prevalence of the disease and to identify aetiological agents as well as the risk factors. A cross-sectional study was carried out in the Otorhinolaryngology Department of the University Teaching Hospital of Yopougon from September 2007 to February 2008. For laboratory investigation, specimens were collected by means of a sterile swab. Samples were inoculated on Sabouraud's Dextrose Agar with and without antibiotics and incubated at 30°C for a period of 1 to 2 weeks. Identification was performed by direct microscopic examination on Cotton Blue Mount preparation and slide culture examination was used for differentiation of morphology. Biotyping was performed using Carbohydrate Fermentation tests, Carbohydrate Assimilation Tests (galerie Api 20 CAux TM - Sanofi Pasteur), Germ tube Test, detection of chlamydospore formation on corn meal agar. A total of 110 patients (sex-ratio=1.2) with suspected cases of otomycosis were investigated. Itching, otalgia, and hypoacusis were the symptoms reported by the patients and the apparent signs were debris in the ear, scabs and inflammation of the external auditory meatus. Of these, 88 cases (80%) were confirmed specifically of mycotic etiology on the basis of positive culture with 92 isolates consisting of yeasts (65.2%) and moulds (34.8%). The predominant etiological agents were Aspergillus flavus (28.4%), Candida guilliermondii (19.3%) and Candida parapsilosis (18.2%). The predisposing factors included previous otological pathology (P=0.010), frequent scratching of the external ear canal and use of ear drops (RR=3.47; IC 95%=1.3-9.27). This study revealed the great

  1. Mechanisms of Action and Dose-Response Relationships Governing Biological Control of Fusarium Wilt of Tomato by Nonpathogenic Fusarium spp.

    Science.gov (United States)

    Larkin, R P; Fravel, D R

    1999-12-01

    ABSTRACT Three isolates of nonpathogenic Fusarium spp. (CS-1, CS-20, and Fo47), previously shown to reduce the incidence of Fusarium wilt diseases of multiple crops, were evaluated to determine their mechanisms of action and antagonist-pathogen inoculum density relationships. Competition for nutrients, as represented by a reduction in pathogen saprophytic growth in the presence of the biocontrol isolates, was observed to be an important mechanism of action for isolate Fo47, but not for isolates CS-1 and CS-20. All three biocontrol isolates demonstrated some degree of induced systemic resistance in tomato (Lycopersicon esculentum) and watermelon (Citrullus lanatus) plants, as determined by split-root tests, but varied in their relative abilities to reduce disease. Isolate CS-20 provided the most effective control (39 to 53% disease reduction), while Fo47 provided the least effective control (23 to 25% reduction) in split-root tests. Dose-response relationships also differed considerably among the three biocon-trol isolates, with CS-20 significantly reducing disease incidence at antagonist doses as low as 100 chlamydospores per g of soil (cgs) and at pathogen densities up to 10(5) cgs. Isolate CS-1 also was generally effective at antagonist densities of 100 to 5,000 cgs, but only when pathogen densities were below 10(4) cgs. Isolate Fo47 was effective only at antagonist densities of 10(4) to 10(5) cgs, regardless of pathogen density. Epidemiological dose-response models (described by linear, negative exponential, hyperbolic saturation [HS], and logistic [LG] functions) fit to the observed data were used to quantify differences among the biocontrol isolates and establish biocontrol characteristics. Each isolate required a different model to best describe its dose-response characteristics, with the HS/HS, LG/HS, and LG/LG models (pathogen/biocontrol components) providing the best fit for isolates CS-1, CS-20, and Fo47, respectively. Model parameters (defining effective

  2. Transmission of Phytophthora ramorum in Mixed-Evergreen Forest in California.

    Science.gov (United States)

    Davidson, Jennifer M; Wickland, Allison C; Patterson, Heather A; Falk, Kristen R; Rizzo, David M

    2005-05-01

    ABSTRACT During 2001 to 2003, the transmission biology of Phytophthora ramorum, the causal agent of sudden oak death, was studied in mixedevergreen forest, a common forest type in northern, coastal California. Investigation of the sources of spore production focused on coast live oak (Quercus agrifolia) and bay laurel (Umbellularia californica), dominant hosts that comprised 39.7 and 46.2% of the individuals at the study site, respectively. All tests for inoculum production from the surface of infected coast live oak bark or exudates from cankers were negative. In contrast, sporangia and chlamydospores were produced on the surface of infected bay laurel leaves. Mean number of zoospores produced from infected bay laurel leaves under natural field conditions during rainstorms was 1,173.0 +/- SE 301.48, and ranged as high as 5,200 spores/leaf. P. ramorum was recovered from rainwater, soil, litter, and streamwater during the mid- to late rainy season in all 3 years of the study. P. ramorum was not recovered from sporadic summer rains or soil and litter during the hot, dry summer months. Concentrations of inoculum in rainwater varied significantly from year to year and increased as the rainy season progressed for the two complete seasons that were studied. Potential dispersal distances were investigated for rainwater, soil, and streamwater. In rainwater, inoculum moved 5 and 10 m from the inoculum source. For soil, transmission of inoculum was demonstrated from infested soil to bay laurel green leaf litter, and from bay laurel green leaf litter to aerial leaves of bay laurel seedlings. One-third to one-half of the hikers tested at the study site during the rainy season also were carrying infested soil on their shoes. In streamwater, P. ramorum was recovered from an unforested site in pasture 1 km downstream of forest with inoculum sources. In total, these studies provide details on the production and spread of P. ramorum inoculum in mixed-evergreen forest to aid

  3. Drug resistance of yeasts isolated from oropharyngeal candidiasis in aids patients Resistência à drogas de leveduras isoladas de candidíase orofaríngea em pacientes com Aids

    Directory of Open Access Journals (Sweden)

    Maria do Rosário Rodrigues Silva

    1998-10-01

    Full Text Available Candida spp was isolated from 59 (68.60% out of eighty six samples of oral mucosa of AIDS patients. The identification, based or the production of a germ tube and chlamydospores, and on the assimilation and fermentation of carbohydrates, revealed 52 strains (88.13% of C. albicans, 4 (6.77% of C. tropicalis and 3 (5.08% of C. krusei. The susceptibility of these strains to amphotericin B, flucytosine, itraconazole, fluconazole and ketoconazole was determined using the agar dilution method. Comparing the minimum inhibitory concentration values found in the susceptibility test with the serum levels achieved by these drugs, only 8.47% and 5.08% of the yeasts strains proved to be resistant to amphotericin B and flucitosyne, respectively. A high frequency of strains resistant to azole derivatives (25.42%, to itraconazole, 45.76%, to ketoconazole and 66.10% to fluconazole was observed.Entre oitenta e seis amostras da mucosa oral de pacientes com AIDS, 59 (68,60% foram positivas para leveduras do gênero Candida. A identificação, feita pela produção de tubo germinativo e clamidósporos e através de assimilação e fermentação de hidratos de carbono, revelou 52 cepas (88,13% de C.albicans, 4 (6,77% de C. tropicalis e 3 (5,08% de C.krusei. Avaliação destas leveduras para susceptibilidade in vitro frente a anfotericina B, flucitosina, itraconazol, fluconazol e cetoconazol, foi realizada pelo método de diluição em ágar. Comparando-se os valores de concentração inibitória mínima encontrados com os níveis séricos alcançados por estes antifúngicos verificou-se que apenas 8,47% e 5,08% das 59 leveduras foram resistentes a anfotericina B e flucitosina, respectivamente. Foi registrada uma percentagem de cepas resistentes aos derivados azólicos, sendo 25,42% ao itraconazol, 45,76% ao cetoconazol e 66,10% ao fluconazol.

  4. [Molecular epidemiology and antifungal susceptibility of Candida species isolated from urine samples of patients in intensive care unit].

    Science.gov (United States)

    Yüksekkaya, Serife; Fındık, Duygu; Arslan, Uğur

    2011-01-01

    The aims of this study were to analyse the amphotericin B and fluconazole susceptibility and molecular epidemiology of Candida strains (Candida albicans, Candida tropicalis and Candida glabrata) isolated from the urine samples of patients hospitalized in the intensive care unit. Identification of the isolates was done according to microscopic morphology (chlamydospor, blastospor, pseudohyphae and true hyphae) on cornmeal agar, germ tube formation and carbohydrate assimilation patterns (API ID 32C bioMérieux, France). Antifungal susceptibilities of the isolates were determined by in vitro broth microdilution method recommended by Clinical and Laboratory Standards Institute (CLSI). To investigate the clonal relationship of the isolates, randomly amplified polymorphic DNA (RAPD) analysis was performed by using Cnd3 primer. Of the 56 Candida isolates minimum inhibitory concentration (MIC) ranges, MIC50 and MIC90 values for amphotericin B were 0.125-1 µg/ml, 0.125 and 0.5 µg/ml for C.albicans, 0.125-1 µg/ml, 0.25 and 1 µg/ml for C.tropicalis and 0.125-1 µg/ml, 0.25 and 1 µg/ml for C.glabrata, respectively. Fluconazole MIC ranges, MIC50 and MIC90 values were 0.25-4 µg/ml, 0.25 and 0.5 µg/ml for C.albicans, 0.25-16 µg/ml, 0.5 and 1 µg/ml for C.tropicalis and 0.5-64 µg/ml, 8 and 16 µg/ml for C.glabrata, respectively. For amphotericin B, none of the isolates had high MIC values (MIC > 1 µg/ml). While one of the C.glabrata isolates was resistant to fluconazole (MIC ≥ 64 µg/ml), one C.tropicalis and two C.glabrata isolates were dose-dependent susceptible (MIC: 16-32 µg/ml). The results of RAPD analysis indicated an exogenous spread from two clones for C.albicans, one clone for C.glabrata and one clone for C.tropicalis. This study underlines the importance of molecular epidemiological analysis of clinical samples together with hospital environmental samples in terms of Candida spp. To determine the exogenous origin for the related strains and to prevent

  5. Ocorrência de Fusarium solani f. sp. piperis em Piper nigrum no estado de Alagoas Report of Fusariom solani f. sp. piperis in Piper nigrum in the state of Alagoas

    Directory of Open Access Journals (Sweden)

    Juliana Paiva Carnaúba

    2007-03-01

    Full Text Available A pimenta-do-reino (Piper nigrum L. é uma planta trepadeira, pertencente à família Piperaceae. Ela é originária do Sudeste Asiático, sendo a mais comum e importante das especiarias. A fusariose, também conhecida por podridão do pé e podridão das raízes é a principal doença da cultura, de ocorrência restrita ao Brasil. Um isolado de Fusarium sp., encontrado infectando plantas de pimenta-do-reino cv. bragantina no município de União dos Palmares em Alagoas, foi caracterizado morfologicamente e teve sua patogenicidade confirmada em mudas deste hospedeiro. Os macroconídios apresentaram-se falcados, hialinos com três a cinco septos, com dimensões de 30,5 - 26,5 x 6,3 - 4,9 ìm, enquanto os microconídios apresentaram-se hialinos, unicelulares, elípticos ou alantóides medindo 16,6 - 4,9 x 6,5 - 3,3 ìm. Os clamidósporos foram abundantes em meio batata-dextrose-ágar. O isolado foi identificado como Fusarium solani f. sp. piperis Alb. tratando-se do primeiro relato deste patógeno em pimenta-do-reino no estado de Alagoas.The pepper-of the-kingdom (Piper nigrum L. it is a climbing plant, pertaining plant to the Piperaceae family. It is originary the southeastern Asian, being most common and important of the spices. Seedling death, also known for rottenness of the foot and rottenness of the root is the main illness of the culture, restricted occurrence to Brazil. Isolated of Fusarium sp., found contamined plants of bragantina pepper-do-kingdom cv. in the city of União dos Palmares in Alagoas, was characterized morphologycament and had its pathogenicity confirmed in changes of this host. The macroconidia slightly curved, typically canoe-shaped, hyaline with three the five septate, measuring 30,5 - 26,5 x 6,3 - 4,9 ìm. Microconidia hyaline, unicellulars, ellipticals or allantoises measuring 16,6 - 4,9 x 6,5 - 3,3 ìm. The chlamydospores had been abundant in half potato-dextrose-agar. The isolated one was identified as to Fusarium

  6. 高分辨熔解曲线技术检测阴道念珠菌分型的研究%Identification of Common Vaginal Candida Species by High Resolution Melting Curve Analysis

    Institute of Scientific and Technical Information of China (English)

    葛玮; 骆志成; 魏玉平; 韩赛楠; 周雅丽

    2013-01-01

    Objective To study the feasibility of identifing common pathogenic Candida clinically isolated from patients with vulvovaginal candidasis by high-resolution melting curve analysis ( HRM) method. Methods Germ tube test, chlamydospore test, CHROMagar Candida and API20 kit system were applied to separate non-C. albicans strains from C. albicans. HRM was used to amplify internal transcribed spacer regions of ribosomal DNA from 5 type strains of 5 pathogenic Candida spp. and 80 clinical Candida isolates. Results Five types of graphic were obtainted after amplifycation from 5 Candida spp. by high-resolution melting curve a-nalysis. Conclusion Candida albicans is the most common pathogenic yeast in the vulvovaginal candidiasis (77.50% ). HRM is able to differentiate clinical Candida species and resulted in being specific, and stable, which can be a good addition to traditional diagnostic approach.%目的 探讨采用高分辨熔解曲线方法鉴定常见致病性念珠菌的可行性,为外阴阴道念珠菌病的分子流行病学及病原学研究奠定基础.方法 用芽管试验、厚壁孢子试验、科玛嘉(CHROMagar)显色培养基及API20C AUX酵母菌鉴定系统对临床致病性念珠菌进行鉴定,然后对5株标准株和80株临床分离株的基因组DNA内转录间隔区进行聚合酶链反应,对扩增产物进行高分辨熔解曲线分型.结果 5株念珠菌标准株和80株临床株聚合酶链反应扩增后,通过熔解曲线技术分析产生5种不同的峰图,即得到念珠菌5种分型.结论 外阴阴道念珠菌的主要致病菌是白念珠菌(77.50%),高分辨熔解曲线方法鉴定常见的致病性念珠菌特异性强、稳定性好,是传统鉴别方法的有益补充.

  7. In-vitro predatory activity of nematophagous fungi from Costa Rica with potential use for controlling sheep and goat parasitic nematodes

    Directory of Open Access Journals (Sweden)

    Natalia Soto-Barrientos

    2011-03-01

    Full Text Available In tropical and subtropical regions of the world, parasitic diseases are a main cause of losses in livestock productivity. The increased acquired resistence to anthelmintics by gastrointestinal nematodes, requires biological control be considered as a potential feasible and effective alternative. The most effective natural soil enemies of nematodes are nematophagous fungi. In order to collect and identify predator nematophagous fungi (PNF, samples were obtained from 51 farms distributed throughout the seven provinces of Costa Rica. The origin samples included: soil from different crops (potatoes, tomatoes, bananas, ornamental plants, squash and coffee; animal feces (cattle, sheep, goat and horse; soil and fallen leaves from forest; and plants with signs of nematode infection. Each sample was processed using three techniques for the extraction of fungi from soil: sprinkling technique, soil dilution and humidity chamber. Twenty four strains of nematophagous fungi were found in 19 farms; 83.3% of the fungi were isolated by sprinkling technique. The following fungi were idenified: Arthrobotrys oligospora (n=13; Candelabrella musiformis (n=9; and for the first time there was isolation of A. conoides (n=1 and A. dactyloides (n=1 in the country. Moreover, 16 strains from Trichoderma (n=13, Beauveria (n=1, Clonostachys (n=1 and Lecanicillium (n=1 were obtained. In addition, pH of each possible fungal isolation source was measured, and it varied from 5.2 to 9.9, however PNF isolates fell within the range of 5.6 to 7.5. The PNF strains were cultivated in four different media for the production of chhlamydospores: potato dextrose agar (PDA; corn meal agar (CMA; malt extract agar (MEA and potato carrot agar (PCA. Out of these cultures, 95.8% of the strains formed chlamydospores primarily in the PCA. Of these strains, the profilic spore producers were subjected to ruminant artificial gastrointestinal conditions. A total of 14 fungi were tested, out of which

  8. In-vitro predatory activity of nematophagous fungi from Costa Rica with potential use for controlling sheep and goat parasitic nematodes.

    Science.gov (United States)

    Soto-Barrientos, Natalia; de Oliveira, Jaqueline; Vega-Obando, Rommel; Montero-Caballero, Danilo; Vargas, Bernardo; Hernández-Gamboa, Jorge; Orozco-Solano, Claudio

    2011-03-01

    In tropical and subtropical regions of the world, parasitic diseases are a main cause of losses in livestock productivity. The increased acquired resistence to anthelmintics by gastrointestinal nematodes, requires biological control be considered as a potential feasible and effective alternative. The most effective natural soil enemies of nematodes are nematophagous fungi. In order to collect and identify predator nematophagous fungi (PNF), samples were obtained from 51 farms distributed throughout the seven provinces of Costa Rica. The origin samples included: soil from different crops (potatoes, tomatoes, bananas, ornamental plants, squash and coffee); animal feces (cattle, sheep, goat and horse); soil and fallen leaves from forest; and plants with signs of nematode infection. Each sample was processed using three techniques for the extraction of fungi from soil: sprinkling technique, soil dilution and humidity chamber. Twenty four strains of nematophagous fungi were found in 19 farms; 83.3% of the fungi were isolated by sprinkling technique. The following fungi were identified: Arthrobotrys oligospora (n = 13); Candelabrella musiformis (n = 9); and for the first time there was isolation of A. conoides (n = 1) and A. dactyloides (n = 1) in the country. Moreover, 16 strains from Trichoderma (n=13), Beauveria (n = 1), Clonostachys (n = 1) and Lecanicillium (n = 1) were obtained. In addition, pH of each possible fungal isolation source was measured, and it varied from 5.2 to 9.9, however PNF isolates fell within the range of 5.6 to 7.5. The PNF strains were cultivated in four different media for the production of chhlamydospores: potato dextrose agar (PDA); corn meal agar (CMA); malt extract agar (MEA) and potato carrot agar (PCA). Out of these cultures, 95.8% of the strains formed chlamydospores primarily in the PCA. Of these strains, the profilic spore producers were subjected to ruminant artificial gastrointestinal conditions. A total of 14 fungi were tested, out

  9. The pathogen causing mango malformation in Jinsha River Dry-hot Valley, China%金沙江干热河谷地区芒果畸形病的病原菌

    Institute of Scientific and Technical Information of China (English)

    杨顺锦; 詹儒林; 柳凤; 赵艳龙; 常金梅; 何衍彪

    2011-01-01

    从金沙江干热河谷地区采集芒果畸形病组织,运用柯赫氏法则证实分离物MG6为该病的致病菌.菌株MG6在马铃薯蔗糖琼脂培养基(PSA)上菌丝白色,无色素产生,米饭培养基浅粉红色;在康乃馨叶片培养基(CLA)上以单瓶梗或复瓶梗假头状产孢,不产生链状孢子;小型分生孢子卵形或长椭圆形,具0-1个分隔,3.1-10.2×1.5-2.2μm;大型分生孢子呈镰刀形,通常3个分隔,18-38×1.8-2.4μm.EF-Iα测序结果在Fusarium数据库中进行同源性分析显示,菌株MG6与F.mangiferae的同源性最高,达99.68%.综合培养性状、形态学特征和EF-Iα序列分析,将菌株MG6鉴定为Fusarium mangiferae.%Mango tissue samples infected by malformation disease were collected from Jinsha River Dry-hot Valley and the fungal strains were isolated after surface sterilization. Isolate MG6 was confirmed to be the pathogen of this disease through Koch's rules.Based on morphological characteristics and EF-1α sequencing, isolate MG6 was identified as Fusarium mangiferae. The colony of the strain was white and pigment was not formed on Potato Sugar Agar (PSA). Pigmentation on rice medium was pink. On Carnation Leaf Agar (CLA) medium, microconidia formed false head on branched monophialides or polyphialidas, and conidia in chains were not observed. Microconidia are ovate to long-oval, 0-1-septate, 3.1-10.2× 1.5-2.2μm. Macroconidia are falculate, 3-5-septate,18-38× 1.8-2.4μm. Chlamydospores are absent. The EF-1α region of the pathogen was amplified and sequenced. A BLAST search through the Fusarium database (http://isolate.fusariumdb.org) showed that the identity of EF-1α sequence of isolate MG6 to that of Fusarium mangiferae NRRL 25226, the closest match was 99.68%, confirming the morphological identification of the isolate.

  10. Phylogenetic Analysis and Detection on the Major Ligninolytic Enzymes of Hericium erinaceum Strain CB1%猴头菌菌株CB1的系统发育分析与木质素降解酶的检测

    Institute of Scientific and Technical Information of China (English)

    尹立伟; 池玉杰

    2013-01-01

    首先对猴头菌菌株CBI进行培养特性观察,表明菌株能产生较多的厚垣孢子;对其ITS序列进行扩增(GenBank登录号为GU584100),并与猴头菌属5个种的17个不同地域菌株进行基于ITS序列的系统发育分析,结果表明菌株CB1与猴头菌同种其他菌株遗传距离较近并聚类在一起.明确该菌株的分类地位后,对其进行木质素降解酶系统的检测,结果表明猴头菌可产生锰过氧化物酶(MnP)和漆酶(laccase),但不产生木质素过氧化物酶(LiP).MnP和漆酶的酶活性变化是有规律的,Mn2是猴头菌产生MnP的必要因子,而漆酶的产生则不受该条件的制约.在含Mn2+的LNAS培养基中加入木屑为底物的条件下,猴头菌MnP最大酶活性为45.56 U·L-1,漆酶最大酶活性为61.85 U·L-1.%Researches on ligninolytic enzymes of white-rot fungi could lay a foundation for exploring their degrading mechanism and expression and regulation mechanism of genes encoding for them.The study firstly observed and described the cultural characteristic of Hericium erinaceum strain CB1,result showed that CB1could produce some chlamydospores.Then,its ITS sequence was amplified (GenBank accession number:GU584100),and phylogenetic analyses was made based on the ITS sequences for 5 species including 17 different regional strains from Hericium,results showed that H.erinaceum strain CB1 and other strains from H.erinaceum were nearer in genetic distance and clustered together with them.After the classification status of H.erinaceum strain CB1 was fixed,its major ligninolytic enzymes were detected.The results indicated that H.erinaceum could produce MnP and laccase simultaneously,but no LiP excreted.The activities of MnP and laccase are regular.Mn2 + was proved to be the essential factor for H.erinaceum to produce MnP,but not for laccase.The highest MnP and laccase activity were reached when sawdust was added to LNAS culture solution with Mn2+ substrate which were 45.56 U·L-1 and 61

  11. An Analysis of Biological Characteristics of the Parasitic Fusarium fungi on Tibetan Cordyceps sinensis%西藏冬虫夏草寄生镰孢属真菌生物学特性分析

    Institute of Scientific and Technical Information of China (English)

    许鹏辉; 邢顺林; 段双全; 张正果

    2012-01-01

    [Objective]This study aimed to analyze the biological characteristics of parasitic Fusarium fungi on Tibetan Cordyceps sinensis.[Method]Fusarium fungi was isolated from fresh Tibetan Cordyceps sinensis as the experimental material, to observe the strain and spore mor phology.[Result]The isolated Fusarium fungus strain grew lushly on rice medium, with white and villiform mycelium, and the villous stroma appeared in colors from beige to pink. After cultivated for two weeks at (18 ?)t, the Fusarium fungus strain produced milky white protru sions containing pale yellow chlamydospores, which were divided into microconidium and macroconidium based on the sizes. According to Ain-sworth' s classification system, the isolated Fusarium strain was identified as a fungus of genus Fusarium in order Tuberculariales of class Hy-phomycetes. Further observation identified three types of macrocondium, and two of them showed distinct morphology, which was not de scribed in Ainsworth's classification system.[Conclusion]The structure of the strain isolated from Tibetan Cordyceps sinensis is significantly different from that of Fusarium fungi recorded in relevant literatures, which requires further investigation.%[目的]对西藏冬虫夏草寄生镰孢属真菌进行生物学特性分析.[方法]以从新鲜冬虫夏草体上分离得到了镰刀菌菌株为材料,对其进行菌株和孢子形态观察.[结果]此种菌株在大米培养基上生长茂盛,菌丝呈白色绒毛状,基质呈米黄色到粉红色;菌株在(18±4)℃条件下培养2周后,产生乳白色突起,里面有淡黄色的厚垣孢子,分大小2种孢子;通过安斯沃斯分类系统查阅分离到的菌株属于丝孢纲瘤座孢目镰孢属的一种;对菌株的大孢子观察发现有3种类型大孢子,而其中2种的形态比较特别,在安斯沃斯分类系统中未有描述.[结论]此次从西藏冬虫夏草上分离到的菌株,与查阅相关资料记载的镰孢属真菌结构有很大区别,有待于做进一步研究.

  12. Investigation of Biological Characteristics of Parasitic Fusarium Fungi from Tibetan Cordyceps sinensis%西藏冬虫夏草寄生镰孢属真菌生物学特性分析

    Institute of Scientific and Technical Information of China (English)

    许鹏辉; 邢顺林; 段双全; 张正果

    2012-01-01

    [Objective] This study aimed to investigate the biological characteristics of parasitic Fusarium fungi from tibetan Cordyceps sinensis. [Method] A Fusarium strain was isolated from fresh tibetan Cordyceps sinensis as the experimental material, to observe the morphologies of Fusarium mycelium and spores. [Result] The isolated Fusarium fungus strain grew lushly on rice medium, with white and villiform myceliurn, and the villous stroma appeared in colors from beige to pink. After cultivated at (18 ± 4) ℃ for 14 d, the Fusarium strain produced milky white protrusions containing pale yellow chlamydospores, which can be divided into microconidiums and macroconidiums based on the different sizes. According to Ainsworth's classification system, the isolated strain belongs to Fusarium, Tuberculariales, Hyphomycetes, adelomycete subphylum. Further observation identified three types of macroconidium, and two of them showed distinct morphology, which was not described in Ainsworth's classification system. [Conclusion] The structure of the strain isolated from tibetan Cordyceps sinensis is significantly different from that of Fusariurn fungi recorded in relevant literatures, which requires further investigation.%[目的]对西藏冬虫夏草寄生镰孢属真菌进行生物学特性分析。[方法]以从新鲜冬虫夏草体上分离得到了镰刀菌菌株为材料,对其进行菌株和孢子形态观察。[结果]此种菌株在大米培养基上生长茂盛,菌丝呈白色绒毛状,基质呈米黄色到粉红色;菌株在(18±4)℃条件下培养2周后,产生乳白色突起,里面有淡黄色的厚垣孢子,分大小2种孢子;通过安斯沃斯分类系统查阅分离到的菌株属于丝孢纲瘤座孢目镰孢属的一种;对菌株的大孢子观察发现有3种类型大孢子,而其中2种的形态比较特别,在安斯沃斯分类系统中未有描述。[结论]此次从两藏冬虫夏草上分离到的菌株,与查阅相关资

  13. First interception of Verticillium albo-atrum in Fangchenggang of Guangxi%广西防城港首次截获苜蓿黄萎病菌

    Institute of Scientific and Technical Information of China (English)

    黄胜光; 卢兆山; 邱世明; 奚国华; 陆道; 钟恒禄

    2012-01-01

    从一批进境的美国苜蓿草样品中保湿分离得到了3株与苜蓿黄萎病菌(Verticillium albo-atrum)相似的目标菌VA1、VA2、VA3.该目标菌在PDA上生长迅速,菌丝生长0.8~1.0 mm/d,2~3 d即可生成肉眼可见的菌落斑点;菌落为白色圆形,边缘规则呈圆形,菌丝较致密,气生菌丝较少,菌落中心乳白色奶冻状;培养4~5 d即后产生气生典型轮枝状分生孢子梗,7~8 d后菌落中央表面因产生休眠菌丝开始变成黑褐色至黑色,20 d后菌落的表面和背面大部分均变黑色,仍不产生微菌核和厚垣孢子.该目标菌的纯培养用V.albo-atrum特异引物Vaa1/Vaa2进行检测,PCR 扩增后得到预期330 bp的产物片段,产物序列与V.albo-atrum相应序列的相似性为100%.从而鉴定确认该目标菌为苜蓿黄萎病菌V.albo-atrum.%Three strains of the fungus, namely VA1, VA2 and VA3, were isolated from a batch of alfalfa samples, which were imported from USA and incubated under moist conditions, demonstrating the characters similar to V. Albo-atrum. The strains grew rapidly on the PDA, with the colony growing at 0.8 - 1. Omm/d. After 2-3 days, the spot colony could be seen on the PDA. In addition, the colony had a regular and rounded margin with white compact mycelium and fewer aerial mycelia. The target fungus produced typical round aerial branched co-nidiophores after 4-5 days, and then became dark brown to black along with production of resting hyphae at the centre of the colony after 7-8 days, and the color of the surface and most of the back of the colony changed to black 20 days later, but still could not produce micro-sclerotia and chlamydospores. The pure cultures of the target germ were detected by the specific primers Vaal/Vaa2. As expected, a 330 bp fragment was obtained by PCR amplification. The similarity between the product and corresponding sequence in V. Albo-atrum was 100%. Therefore, it was confirmed that the target germ was V. Albo-atrum.

  14. 荧光假单胞菌拮抗菌株对烟草疫霉的抑菌机制及控病效果%Antagonistic mechanism of Pseudomonas fluorescens strains against Phytophthora nicotianae and biocontrol effect on tobacco black shank

    Institute of Scientific and Technical Information of China (English)

    董国菊; 马冠华; 肖崇刚

    2012-01-01

    To explore the antagonistic mechanism of rhizospheric bacteria against Phytophthora nicotianae van Breda de Haan,five antagonistic Pseudomonas fluorescens strains were isolated from rhizospheric soils of tobacco fields in Chongqing.Efficient antagonistic strain against P.nicotianae was screened using dual culture technique and metabolites inhibitory test.Among these strains,P-72-10 showed the highest suppressive effect;it produced an inhibition zone of 13.0mm(radius) and an inhibitory rate at 68.57%.Furthermore,the growth of pathogen's hypha was also suppressed by the extracellular metabolites of strain P-72-10 from 25.39% to 46.03%.P.nicotianae was observed microscopically excessive branching of mycelia and malformation of mycelia tips;thick-walled cells with concentrated plasmas and chlamydospore-like cells.When tested on the tobacco plants grown in greenhouse,strain P-72-10 got a good biocontrol effect on tobacco black shank infection and effects on the resistant and susceptible varieties of tobacco were 53.57% and 66.37% respectively.%为探讨烟草根际生防细菌对烟草疫霉Phytophthora nicotianae的抑菌机制,从重庆地区连作烟田健康烟株根际土壤分离获得5株荧光假单胞菌Pseudomonas fluorescens拮抗菌株。通过平板对峙及代谢产物抑菌试验筛选对烟草疫霉具有高效拮抗作用的菌株,其中,P-72-10菌株抑菌效果最强,抑菌带半径达13.0 mm,相对抑制率为68.57%,且该菌株代谢产物对烟草疫霉菌丝生长有明显的抑制作用,相对抑制率达25.39%~46.03%;显微观察发现该菌株可引起烟草疫霉菌丝的分支增多,菌丝顶端膨大呈畸形,多数菌丝中间或顶端细胞的细胞壁加厚、原生质浓缩和产生类似厚壁孢子的细胞。在温室盆栽条件下P-72-10菌株对烟草黑胫病也表现出良好的控病效果,对抗病和感病品种的相对防效分别为53.57%和66.37%。

  15. 辣木果荚腐病病原菌分离及鉴定%Isolation and identification of pathogens causing pod rot of Moringa oleifera

    Institute of Scientific and Technical Information of China (English)

    蔡志英; 曾艳华; 熊斌; 刘一贤; 杨焱; 龙继明; 殷振华; 郭涵; 李海泉

    2016-01-01

    【目的】明确辣木果荚腐病病原菌种类及其分类地位,为辣木果荚腐病防治提供理论依据。【方法】对云南省西双版纳州辣木种植基地感病、带黑色颗粒物病残体的辣木果荚进行症状观察、病原菌分离培养、致病性测定、显微形态特征观察、ITS和β-tubulin基因序列分析。【结果】辣木果荚腐病病原菌的分生孢子不分隔、透明,孢子顶端呈尖锥形弯曲,基部平截,具油滴,大小为15.7~22.1μm×2.5~4.3μm;厚垣孢子壁厚,呈黑褐色,簇生或成链状。该菌株ITS和β-tubulin基因的序列与Colletotrichum chlorophyti菌株IMI103806的同源性高达99%(ITS登录号:GU227894;TUB2登录号:GU228188)。多基因联合系统发育分析结果表明,供试菌株与兰生炭疽菌(C. chlorophyti)具有很近的遗传关系。【结论】兰生炭疽菌(C. chlorophyti)能侵染辣木引起果荚腐病,是为害辣木果荚的致病菌。%[Objective]In order to provide theory basis for controlling pod rot of Moringa oleifera, the pathogen was i-dentified, and its taxonomic status was studied. [Method]The infected M. oleifera pods with black particles were collected from M. oleifera planting base in Xishuangbanna, Yunnan province. Based on disease symptom observation, morphological characteristics of pathogen, pathogenicity, rDNA-ITS and β-tubulin gene sequence analysis, the pathogen causing pod rot of M. oleifera was identified. [Result]The conidia of pathogen were aseptate, hyaline, smooth, curved with tapered ends and a truncated base, and ranged from 15.7-22.1 μm×2.5-4.3 μm in size. Chlamydospores were dark brown, thick-walled, and fascicled or catenulate. The gene sequences of ITS and TUB2 gene showed 99% homology with Colletotrichum chlorophyti strain IMI103806 (ITS accession number: GU227894; TUB2 accession number: GU228188). Multi-gene phylogenetic analysis showed that the tested strain had the closest genetic

  16. In-vitro predatory activity of nematophagous fungi from Costa Rica with potential use for controlling sheep and goat parasitic nematodes

    Directory of Open Access Journals (Sweden)

    Natalia Soto-Barrientos

    2011-03-01

    Full Text Available In tropical and subtropical regions of the world, parasitic diseases are a main cause of losses in livestock productivity. The increased acquired resistence to anthelmintics by gastrointestinal nematodes, requires biological control be considered as a potential feasible and effective alternative. The most effective natural soil enemies of nematodes are nematophagous fungi. In order to collect and identify predator nematophagous fungi (PNF, samples were obtained from 51 farms distributed throughout the seven provinces of Costa Rica. The origin samples included: soil from different crops (potatoes, tomatoes, bananas, ornamental plants, squash and coffee; animal feces (cattle, sheep, goat and horse; soil and fallen leaves from forest; and plants with signs of nematode infection. Each sample was processed using three techniques for the extraction of fungi from soil: sprinkling technique, soil dilution and humidity chamber. Twenty four strains of nematophagous fungi were found in 19 farms; 83.3% of the fungi were isolated by sprinkling technique. The following fungi were idenified: Arthrobotrys oligospora (n=13; Candelabrella musiformis (n=9; and for the first time there was isolation of A. conoides (n=1 and A. dactyloides (n=1 in the country. Moreover, 16 strains from Trichoderma (n=13, Beauveria (n=1, Clonostachys (n=1 and Lecanicillium (n=1 were obtained. In addition, pH of each possible fungal isolation source was measured, and it varied from 5.2 to 9.9, however PNF isolates fell within the range of 5.6 to 7.5. The PNF strains were cultivated in four different media for the production of chhlamydospores: potato dextrose agar (PDA; corn meal agar (CMA; malt extract agar (MEA and potato carrot agar (PCA. Out of these cultures, 95.8% of the strains formed chlamydospores primarily in the PCA. Of these strains, the profilic spore producers were subjected to ruminant artificial gastrointestinal conditions. A total of 14 fungi were tested, out of which

  17. Nail and skin lesions caused by scytalidium dimidiatum in Medellín (Colombia, 1990-1999: report of 128 cases and review of the name of the agent Lesiones ungueales y cutáneas por Scytalidium dimidiatum en Medellín (Colombia, 1990-1999. Presentación de 128 casos y revisión del problema del nombre del agente

    Directory of Open Access Journals (Sweden)

    Jaime Carmona Fonseca

    2000-03-01

    hyphae alone or with chlamydospores (21% and yeast cells alone or with pseudohyphae (5%. There was no significant difference between the results of nail and skin Objetivo:Revisar el problema de la denominación del agente y presentar los rasgos epidemiológicos de 128 casos de lesiones en uñas o en piel por Scytalidium dimidiatum. Diseño: Estudio descriptivo, en parte retrospectivo (1990-1996 y en parte prospectivo (1997-1999. Marco de referencia: hasta hace poco tiempo hubo problemas con la nomenclatura del agente, pero ahora existen los argumentos para despejar las dificultades y ese es el primer objetivo del trabajo: presentar esos argumentos e indicar la manera de usar bien uno u otro nombre. Por otra parte, la importancia del S. dimidiatum como causa de lesiones en humanos aumenta cada día. Este informe, restringido a lesiones en uñas y piel, recoge una cifra muy alta de pacientes (128 casos, correspondientes al lapso 1990-1999. Métodos: los autores revisaron cada uno de los registros de laboratorio y, aplicando criterios de consenso, resolvieron las dudas. Se utilizaron criterios estándar de identificación micológica. El análisis estadístico de los datos se hizo con el programa EpiInfo versión 6.04. y consistió, principalmente, en evaluar la asociación de variables con la chi cuadrada y en comparar posiciones de datos continuos y ordenados según su magnitud con la prueba H de Kruskal-Wallis. Resultados: los diferentes nombres del agente (Nattrassia mangiferae, Scytalidium dimidiatum, Scytalidium hialinum, Scytalidium lignicola, Hendersonula toruloidea deben usarse en situaciones precisas, que se describen aquí. Se estudiaron 128 muestras de las cuales se aisló por cultivo Scytalidium dimidiatum: 102 en uñas (92% en pies y 26 en lesiones extraungueales (73% interdigitales en pies. Las características epidemiológicas de un caso típico de lesión ungueal por S. dimidiatum indican que en el 41% de las veces es una mujer, de 21 a 49 años, que usa