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1.
Summary A brief discussion has been given of various devices available for the determination of micro-organisms in air. In order to investigate the efficiency of some of these devices it proved desirable to work with artificially contaminated air. Hereto clouds of spores ofBacillus cereus were produced with the aid of a modified model of aDe Vilbiss 40 nebulizer.Comparative tests were made with theFolin-bubbler, theWheeler-bubbler, theMoulton-atomizer and the capillary impinger as used byRosebury for the determination of the spore concentration in the contaminated air. The latter device proved to be by far the most efficient, 99% or more of the spores being retained by this simple apparatus.  相似文献   

2.
The large, outdoor Islip Yard Waste Composting Facility on Long Island, New York was investigated as a source of airborne fungus spores. The Burkard-Hirst volumetric spore trap was used for the first extensive sampling of small mold spores for this application. Samplers were operated continuously from 21 August to 30 November 1992 in the facility and in a suburban community about 540 m from the facility. A control site approximately 10 000 m from the facility was also sampled to establish background levels of fungus spores. The facility site had higher average readings ofAspergillus fumigatus spores than did the community and both were higher than the control.A. fumigatus was the only fungus among 30 categories tracked that differed significantly between the facility and control sites. It was also isolated repeatedly from the compost. Higher average levels ofA. fumigatus were measured in the community when winds blew from the facility, and also during times when the compost was moved or mixed at the facility. No correlation was found between wind direction or work times andA. fumigatus conidia at the control site. The study shows that this compost facility can produce a measurable increase in the number of airborneA. fumigatus conidia both at the edge of the facility and at 540 m downwind. It also demonstrates that the Burkard spore trap can be used for monitoring small, airborne mold spores, but it is a difficult and labor intensive task.  相似文献   

3.
Cultures ofMetarhizium anisopliae (Metsch.) Sor.,Beauveria bassiana (Bals.) Vuill.,B. tenella (Delac.) Siem.,Aspergillus fumigatus Fres. andPaecilomyces farinosus (Dicks, exFr.) Brown & Smith were tested for pathogenicity toOryctes rhinoceros L. All the long spored cultures ofM. anisopliae isolated fromOryctes spp. were equally pathogenic toO. rhinoceros. Most of the 23 short spored cultures from other insects caused lesions onOryctes larvae but only 5 isolates were lethal. SomeBeauveria isolates caused brown lesions on larvae but generally these larvae developed into normal adults. One isolate ofB. bassiana fromCarpocapsa pomonella L. killed larvae at the time of pupation. Cultures ofA. fumigatus andP. farinosus were not pathogenic. A method for growingM. anisopliae on oats for large scale field use is described.
Résumé Des cultures deMetarhizium anisopliae, deBeauveria bassiana, deB. tenella, d'Aspergillus fumigatus et dePaecilomyces farinosus ont été examinées en fonction de leurs effets pathogènes surOryctes rhinoceros. Toutes les cultures à spores longues deM. anisopliae isolées desOryctes spp. ont été également pathogènes pourO. rhinoceros. La plupart des 23 cultures à spores courtes obtenues à partir d'autres insectes ont causé des lésions sur les larves d'Oryctes mais cinq seulement ont été mortelles. Certaines souches deBeauveria ont causé des lésions brunes sur les larves mais, en général, ces larves ont donné des adultes normaux. Une culture deB. bassiana isolée deCarpocapsa pomonella a tué les larves au moment de leur métamorphose en chrysalides. Les cultures d'A. fumigatus et deP. farinosus n'ont pas eu d'effet pathogène. Une méthode de culture deM. anisopliae sur avoine pour l'utiliser sur de grandes surfaces est décrite.
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4.
Intramammary inoculation of goats withAspergillus fumigatus spores resulted in the development of mastitis with characteristic gross and microscopic lesions. The mastitis and the lesions were restricted to the infected udder halves only and there was no dissemination of infection to other tissues of the body. The experiment was continued for 45 days. Gross changes in the infected udder were observed up to the 45th day post-infection. The lesions, in general, included variable sized abscesses in the first 15 days followed by development of varying sized greyish-white nodules in the infected udders. Microscopic changes consisted of granulomatous reaction with well developed granulomas in the infected udders. Hyphae and spores ofAspergillus fumigatus could be demonstrated in sections of the infected udders up to 45 days after infection. Reisolation of the fungus consistently was achieved up to 45 days. It is concluded that intramammary inoculation ofAspergillus fumigatus spores in goats leads to chronic granulomatous mastitis.  相似文献   

5.
Intratracheal inoculation of goats withAspergillus fumigatus spores resulted in the development of characteristic gross and microscopic lesions. The lesions were restricted to lungs and there was no dissemination of infection to other tissues of the body except liver in one goat 16 days after infection. The experiment was continued for 37 days. Gross changes in lungs were observed up to the 24th day post-infection. The lesions, in general, included congestion and oedema in the first 6 days followed by the development of varying greyish-white nodules in the lungs. Microscopic changes consisted of granulomatous reaction with well developed granulomas in lungs. Hyphae and conidiophores with fruiting bodies ofAspergillus fumigatus could be demonstrated in sections up to 24 days of infection. Reisolation of the fungus consistently was achieved up to 24 days. It is concluded that intratracheal inoculation ofAspergillus fumigatus spores in goats leads to pulmonary aspergillosis up to 24 days.  相似文献   

6.
Ten strains ofAspergillus fumigatus Fresenius, isolated from human or animal sources, were compared for cultural and serologic characteristics when grown on neopeptone dialysate medium. All strains grew well and antigenic similarities were noted among the strains. Best antigen production occurred after 6 weeks' incubation.  相似文献   

7.
Walter Herfs 《BioControl》1963,8(3):163-181
Zusammenfassung Es wird eine Methode der Wirksamkeitsbestimmung vonBacillus thuringiensis-Pr?paraten beschrieben und an Raupen vonPieris rapae (L.) undLymantria dispar (L.) erprobt. Hierzu wurde eine spezielle Dosierungs-Apparatur konstruiert, die es erm?glicht, bei bekannter Sporenzahl je ml in der Ausgangssuspension eine bestimmbare Sporenzahl je Fl?cheneinheit der behandelten Blattstücke zu erhalten, so dass man anhand der je Larve gefressenen Blattfl?che die je Larve aufgenommene Sporenzahl ermitteln kann. Zur einfacheren und schnelleren Messung der befressenen Blattstücke wurde ein photoelektrisches Frassmessger?t konstruiert. Die Methode erlaubt durch einen Vergleich von Sporenzahl je Larve, gefressener Blattfl?che und Mortalit?t, auch geringe Unterschiede in der Wirksamkeit verschiedenerB. thuringiensis-St?mme, —Variet?ten oder—Pr?parate festzustellen. Je ein Versuch mit 5 Konzentrationen verschiedener Variet?ten desB. thuringiensis (var.sotto, euxoae, alesti, dendrolimus, galleriae, thuringiensis) wurde anPieris rapae undLymantria dispar durchgeführt. Dabei ergab sich nicht nur eine sehr grosse Empfindlichkeit beiP. rapae und eine wesentlich geringere Anf?lligkeit beiL. dispar, sondern die Variet?ten waren auch bei beiden Lepidopteren unterschiedlich in der Reihenfolge ihrer Wirksamkeit. Beginnend beim wirksamsten der geprüften Sporen-” Endotoxin „-Pr?parate lautet die Reihenfolge fürP. rapae: var.galleriae, alesti, dendrolimus, thuringiensis, euxoae undsotto; fürL. dispar dagegen heisst sie: var.dendrolimus, galleriae, euxoae, thuringiensis, alesti undsotto. Anhand der erprobten Konzentrationen ergab sich, dass bei jüngeren Larvenstadien vonP. rapae (L3) wesentlich geringere Sporenzahlen (bzw. Anzahl Toxinkristalle) notwendig sind, um die Raupen abzut?ten, als in der Literatur für ?ltere Larvenstadien (L5) angegeben wird.
Summary For the determination of the effectiveness ofBacillus thuringiensis preparations an apparatus was built which permits to determine the number of spores falling on a particular area of a leaf, if the number of spores in the original suspension is known. Also an instrument is described for photoelectric measuring of leaf hole areas which determines the size of the rest of a leaf, eaten by lepidopterous larvae. Both apparatus were used for experiments to determine the effectiveness of different strains or preparations ofBacillus thuringiensis (var.sotto, euxoae, alesti, dendrolimus, galleriae andthuringiensis) against young larvae ofPieris rapae (L.) andLymantria dispar (L.). The varieties were tested in 5 concentrations. It was found that the susceptibility ofP. rapae against the bacillus is much higher than that ofL. dispar. Since it is possible to find out, by this method, how many spores per larva are necessary to cause a certain mortality, also it is possible to detect small differences in the effect of various bacterial varieties. In the case ofP. rapae it was observed that the number of spores (probably identical with that of toxin crystals) which is needed to kill one average larva, is much less than so far reported for elder instars. It is possible that a small number of spores is sufficient because a multiplication of the pathogen takes place in the larva. The order of effectiveness of the tested varieties was different in both lepidopterous species: forP. rapae it was beginning with the most effective strain, var.galleriae, alesti, dendrolimus, thuringiensis, euxoae andsotto. ForL. dispar the order was var.dendrolimus, galleriae, euxoae, thuringiensis, alesti andsotto.


Die Arbeit erfolgte mit Unterstützung der Deutschen Forschungsgemeinschaft, die auch die Mittel für den Bau der Dosierungs-Apparatur zur Verfügung stellte. Die Untersuchungen wurden gemeinsam mit Herrn Dr.A. Krieg durchgeführt, wobei diesem die mikrobiologischen Arbeiten oblagen.  相似文献   

8.
The hihi (or stitchbird, Notiomystis cincta) is a New Zealand endemic nectivorous forest bird now restricted to one pristine island. Relocation to establish viable hihi populations on other islands has been the main conservation action since the early 1980s. To date, hihi reintroductions to young growth islands have had poor success despite the absence of mammalian predators. It was thought that past failures were due to food limitation, but research suggests that food limitation alone cannot account for their poor survivorship. Post-mortems of dead hihi has shown that aspergillosis caused by Aspergillus fumigatus is a major mortality factor and there is current concern regarding their susceptibility to this fungal disease. In this paper we develop and assess the hypothesis that A. fumigatus limits hihi population viability on modified islands, and suggest that A. fumigatus is a potential indicator species for habitat disturbance. We report that the prevalence of A. fumigatus spores in the soil is much higher in young growth forests and forest edge habitats. Results suggest that hihi mortality rates between islands are potentially due to differential exposure to A. fumigatus spores. We assess relationships between habitat disturbance, A. fumigatus contamination and hihi mortality rates by testing the following predictions: (1) that densities of A. fumigatus spores will be higher on modified islands, (2) that densities of A. fumigatus spores on islands will be correlated with hihi mortality rates and (3) that densities of A. fumigatus spores will be higher at the forest edge than in the interior. We test each of these predictions using soil samples, air samples and samples of nectar from plant species fed on by hihi.  相似文献   

9.
Summary The control by light of the spore germination ofOsmunda cinnamomea L. andO. claytoniana L. has been investigated.This light control is complex, and in order to investigate this control quantitatively the process of germination had to be divided into at least two stages. The first stage of germination leads to the rupture of the exospore, the second step is characterized by the outgrowth of a rhizoid. In a very few percent of our spore population the first stage can occur in total darkness, the second step however does not ever occur in darkness.In the present paper it has been demonstrated, usingO. cinnamomea spores, that the first step of germination is phytochrome controlled, whereas the second step is under photosynthetic control. This was observed withO. claytoniana by a rough action spectrum and in experiments with a CO2-less atmosphere.The germinating spores of these two species ofOsmunda show a very similar behaviour as the spores of the mossFunaria hygrometrica (L.) Sibth. (Bauer andMohr 1959). They behave very differently compared with spores of other ferns, e.g.Dryopteris filix-mas (L.) Schott, where the whole process of germination is exclusively phytochrome controlled (Mohr 1956).

Mit 10 Textabbildungen  相似文献   

10.
Summary This paper deals with four new fungi from the State of Rio Grande do Sul, Brazil.Phaeseptoria stenocalycis Batista, Upadhyay &Da Costa Netto, collected on leaves ofStenocalyx dasyblastus Bert. from Grammado,Phoma jasmino-macrospora Batista, Upadhyay &Da Costa Netto, collected on leaves ofJasminum flexicaule Vahl. from Pôrto Alegre,Melanconium argutidentis Batista, Upadhyay &Da Costa Netto, collected on leaves ofSebastiana argutidens Pex &K. Hoff from Grammado andCercospora caleifoleii Batista, Upadhyay &Da Costa Netto, collected on leaves ofCalea pinnatifida Banks from Pôrto Alegre are described here.Symptoms on the hosts and morphological characters of the fruitings and spores are described and illustrated.Publicação no 456 of IMUFP.  相似文献   

11.
O. F. Esuruoso 《Mycopathologia》1970,42(1-2):187-189
The fung isolated from mouldy processed sheet rubber in Western Nigeria wereAspergillus fumigatus Fres,Aspergillus flavus Link andAspergillus aculeatus Iisuka. When inoculated on sterilized, uninfected sheet rubber, bothA. fumigatus andA. flavus produced symptoms which were similar to those originally observed on mouldy processed sheet from the rubber estate.
Zusammenfassung Die folgenden Pilze sind vom verschimmelten, bearbeiteten Rubber isoliert worden:Aspergillus fumigatus Fres,A. flavus Link andA. aculeatus Iisuka. WennA. fumigatus undA. flavus an sterilisiertem, nicht infiziertem Rubber verimpft worden sind, haben sie identische Läsionen am sterilen Rubber verursacht.
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12.
Urediniospores ofCronartium ribicola J. C. Fisch. exRabenh. were observed within the petiole ofRibes petiolare L. These spores occurred internal to xylem tissues within the region of undifferentiated parenchyma cells (pith). Fungal tissues were sparse and fully differentiated sori were absent.Research Plant Pathologist and Biological Laboratory Technician, USDA Forest Serv., Intermountain Forest and Range Exp. Sta., Ogden, Utah, stationed in Moscow, Idaho83843, at Forestry Sciences Laboratory, maintained in cooperation with the University of Idaho.  相似文献   

13.
In recent yearsAspergillus flavus and aflatoxin production have been noted on several occasions in grain preserved with formic acid. Samples of mouldy barley treated with formic acid and stored in an open bin were investigated for the presence of fungi. In the lower part of the bin there was a clear dominance ofFusarium sporotrichioides, and deoxynivalenol and neosolaniol were detected.A. flavus andA. fumigatus were also present.Paecilomyces variotii occurred, almost as a pure culture, in the upper part of the bin, but no patulin was found. Cultivation of four fungal isolates from these genera on laboratory substrates containing formic acid showedP. variotii to be the most tolerant to formic acid, withstanding 150 mM, but still without patulin production.F. sporotrichioides andA. fumigatus tolerated only 6 mM formic acid. The growth ofA. flavus was reduced and atypical at 60 mM formic acid. Pretreatment ofA. flavus spores with formic acid increased aflatoxin production about 800 times.  相似文献   

14.
M. Melkonian 《Protoplasma》1981,108(3-4):341-355
Summary The flagellar apparatus of the quadriflagellate scaly green algaPyramimonas obovata has been studied in detail and the absolute configuration of the flagellar apparatus has been determined. The flagellar root system is cruciate (4-2-4-2-system). 18 major basal body associated fibrous structures connect the four basal bodies with each other. Each basal body is linked to an adjacent basal body by a unique set of connecting fibres, i.e., the flagellar apparatus does not exhibit 180° rotational symmetry. The flagellar apparatus ofPyramimonas obovata is compared with that of quadriflagellate motile cells of theChlorophyceae sensu Stewart andMattox and the phylogenetic relationships are discussed.  相似文献   

15.
High concentration of inorganic phosphate in the culture medium ofAspergillus fumigatus inhibited ergot alkaloid synthesis. Addition ofl-tryptophan but not mevalonate or 5-methyltryptophan to the above culture restored the alkaloid synthesis to the level found in normal cultures. The decrease in alkaloid synthesis in the fungus accompanies an increase in cell mass, cellular protein and sterol content. Aspartate aminotransferase and alanine aminotransferase activities were significantly increased in the high-phosphate culture. Part of the work was presented at the seminar on “Enzymatic Methods in Mycology” organised by the Czechoslovak Microbiological Society in Brno, Czechoslovakia, in June 1975.  相似文献   

16.
Summary Evans' tube and cellophane agar-disc techniques were used to evaluate the colonization capacity of the soil microbes and fungistasis, respectively. Spore germination ofAlternaria tenuis, Curvularia geniculata, Helminthosporium rostratum andPestalotia sp. was studied on a natural soil. Aspergillus fumigatus was the pioneer colonizer, followed in the order of decreasing colonizing capacity by,A. flavus, A. niger, A. terreus andPenicillium nigricans. Sensitivity of test spores to soil fungistasis declined in the order,C. geniculata → Pestalotia sp. →A. tenuis → H. rostratum. The fungistatic level of the soil samples decreased gradually from side arms 1 to 7 of the Evans tube, inoculated with unsterilized soil from one end. Studies conducted with an inoculum of four soil fungi (A. fumigatus, A. flavus, A. niger, andP. nigricans) as well as those involving fumigation of Evans tube by CS2 also proved the greater colonizing capacity ofA. fumigatus. The level of fungistasis followed closely the colonization pattern of this fungus. When added individually to the soil, all fungi were able to inhibit spore germination of test fungi to some degree or other.  相似文献   

17.
The ability of Aspergillus fumigatus l-amino acid oxidase (l-aao) to cause the resolution of racemic mixtures of dl-amino acids was investigated with dl-alanine, dl-phenylalanine, dl-tyrosine, and dl-aspartic acid. A chiral column, Crownpak CR+ was used for the analysis of the amino acids. The enzyme was able to cause the resolution of the three dl-amino acids resulting in the production of optically pure d-alanine (100% resolution), d-phenylalanine (80.2%), and d-tyrosine (84.1%), respectively. The optically pure d-amino acids have many uses and thus can be exploited industrially. This is the first report of the use of A. fumigatus l-amino acid oxidase for racemic resolution of dl-amino acids.  相似文献   

18.
T. Raghunath 《Mycopathologia》1966,30(3-4):209-215
Summary 1. A new species ofAlternaria isolated from the diseased plants ofCarum copticum L.Peucedanum graveolens Benth. &Hook f. andFoeniculum vulgare Mill. is described and compared with other species affecting Umbelliferae.2. TheCoriandrum isolate described by the writer asAlternaria poonensis Raghunath is a shy sporulator in artificial culture with long beaked muriform spores formed singly at the end of comparatively short conidiophores.3. The isolate from the other three host plantsCarum copticum L.,Peucedanum graveolens Benth. &Hook f. andFoeniculum vulgare Mill. is named asAlternaria umbellifericola sp. nov. and is a profusely sporulating species, forming long chains of spores with rudimentary beak.4. TheCoriandrum isolate (Alternaria poonensis) has a narrower temperature range (25–30° C) than theCarum isolate (20–35° C) for optimum sporulation.5. TheCoriandrum isolate is pathogenic toCarum but not toDaucus carota L.6. TheCarum isolate is pathogenic toDaucus carota but does not infectCoriandrum sativum L.7. TheCoriandrum isolate has a wider host range among the Umbelliferae than theCarum isolate.Part of the M.Sc. thesis submitted to the Poona University, 1964.  相似文献   

19.
E. Biliotti 《BioControl》1956,1(1):45-53
Summary Without discussing the problem of the particular role of Epizootics in natural populations, the author examines the different types of relations existing between entomophagous insects and diseases of their hosts. The consequence for parasites and predators of a possible use of pathogenes as a method of Biological Control of pests is examined with more detail in the case ofP. brassicae L. submitted to sprays with a suspension of spores ofB. thuringiensis Berliner. It is shown that two hymenopterous parasites (Apanteles glomeratus L. Anilastus ebeninus Grav). can survive the death of their host, under certain circumstances. The survival ofA. glomeralus is conditionned by its being in the last larval instar on the day of treatment. The consequence of the disease of the host caterpillar is a shortening of the endoparasitic life of the Braconid. A similar effect can be observed whenP. brassicae caterpillars are treated with a contact insecticide, but in this case,Apanteles larvae are killed by residues on their emergence from the host. There is no direct effect of spore suspensions on the larvae of the parasite. It seems thus possible to adopt bacterial control measures preserving a part of the entomophagous populations.

I.N.R.A., Laboratoire de lutte biologique de La Minière.  相似文献   

20.
Yan X  Gai Y  Liang L  Liu G  Tan H 《Archives of microbiology》2007,187(5):371-378
Alanine racemase is a major component of the exosporium of Bacillus cereus spores. A gene homologous to that of alanine racemase (alrA) was cloned from Bacillus thuringiensis subsp. kurstaki, and RT-PCR showed that alrA was transcribed only in the sporulating cells. Disruption of alrA did not affect the growth and sporulation of B. thuringiensis, but promoted l-alanine-induced spore germination. When the spore germination rate was measured by monitoring DPA release, complementation of the alrA disruptant reduced the rate of l-alanine-induced spore germination below that of even wild-type spores. As previously reported for spores of other Bacillus species, d-alanine was an effective and competitive inhibitor of l-alanine-induced germination of B. thuringiensis spores. d-cycloserine alone stimulated inosine-induced germination of B. thuringiensis spores in addition to increasing l-alanine-induced germination by inhibiting alanine racemase. d-Alanine also increased the rate of inosine-induced germination of wild-type spores. However, d-alanine inhibited inosine-induced germination of the alrA disruptant spores. It is possible that AlrA converted d-alanine to l-alanine, and this in turn, stimulated spore germination in B. thuringiensis. These results suggest that alrA plays a crucial role in moderating the germination rate of B. thuringiensis spores.  相似文献   

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