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1.
Résumé Les auteurs ont découvert, dans le sol roumain, la large présence duMicrosporon nanumFuentes 1956. Ils font mention de certaines particularités des souches isolées du sol, à savoir la forme très variable des macroconidies dont la majorité sont dépourvues de septa, l'absence des microconidies, l'absence du pléomorphisme et le faible pouvoir pathogène envers l'homme et les animaux d'expérience. Toutefois ils ont réussi à inoculer le champignon, avec résultat positif, à l'homme et au cobaye. La disposition selon le type microsporique, du parasite dans le poils du cobaye atteint de mycose expérimentale, de même que la photoluminescence jaune-verdâtre, caractéristique de ses poils, ont permis aux auteurs de considérer leMicrosporon nanum comme un vraiMicrosporon, distinct duMicrosporon gypseum. La large présence dans le sol et le faible pouvoir pathogène prouve, selon les auteurs, que leM. nanum est un saprophyte du sol.
Summary The authors were able to recoverMicrosporon nanumFuentes 1956 from numerous roumanian soil samples. They pointed out some peculiarities of the soil isolates, viz. the very diverse forms of the macroconidia, the lack of pleomorphic change and the low degree of pathogenicity to man and the experiment animals. Nevertheless, they were able to inoculate, with positive result, one isolate in man and Guinea pig. The microsporical type of invasion, the parasite showed in the infected hairs of the Guinea pig, inoculated with one of the strains, so as their characteristic yellow-green fluorescence in the Wood's light, suggests thatMicrosporon nanum is a realMicrosporon, quite distinct fromMicrosporon gypseum. The ubiquitous presence in soil and the low degree of pathogenicity evidences, in the authors opinion, the geophilic and saprophytic nature ofMicrosporon nanum.


(Travail du Centre Dermato-Vénéréologique de Bucarest. Directeur:St. G. Nicolau, membre de l'Académie de la République Populaire Roumaine)  相似文献   

2.
Summary The growth ofMicrosporum Cookei, M. distortum, andM. nanum was compared on solid media containing 23 different carbon sources and 25 different nitrogen sources.M. nanum grew well only on media containing ribose, xylose, levulose, or erythritol as the carbon source.M. distortum andM. Cookei were found to utilize a far greater variety of carbon sources. Both grew well on dextrose, levulose, galactose, mannose, ribose, arabinose, rhamnose, sucrose, cellobiose, lactose, trehalose, melibiose, melezitose, raffinose, dextrin, and mannitol; in additionM. Cookei grew well on xylose, maltose, and erythritol. Aspartic acid, arginine, and citrulline were favorable sources of nitrogen for all three species. M. nanum also grew well on alanine, ornithine, histidine, and proline;M. distortum on glycine, serine, asparagine, glutamic acid, leucine, and cysteine; andM. Cookei on asparagine, tyrosine, ornithine, histidine, leucine, isoleucine, and proline.WithM. Cookei andM. distortum grown in liquid media in shake culture, mannitol was the best carbon source and tyrosine the best of the nitrogen sources tested. Nutritional differences exist among these three species,M. Audouini, M. canis, andM. gypseum.From a thesis, under the direction of Dr.Frederick T. Wolf, submitted in partial fulfillment of the requirements for the degree Master of Arts, August 1961.  相似文献   

3.
Plants flowering together may influence each other’s pollination and fecundity over a range of physical distances. Their effects on one another can be competitive, neutral, or facilitative. We manipulated the floral neighborhood of the high-alpine cushion plant Eritrichium nanum in the Swiss Alps and measured the effects of co-flowering neighbors on both the number of seeds produced and the degree of inbreeding and outbreeding in the offspring, as deduced from nuclear microsatellite markers. Seed set of E. nanum did not vary significantly with the presence or absence of two Saxifraga species growing as near neighbors, but it was higher in E. nanum cushions growing at low conspecific density than in those growing at high density. In addition, floral neighborhood had no detectable effect on the degree of selfing of E. nanum, but seeds from cushions growing at low conspecific density were more highly outbred than seeds from cushions at high density. Thus, there was no evidence of either competition or facilitation between E. nanum and Saxifraga spp. as mediated by pollinators at the spatial scale of our experimental manipulation. In contrast, the greater fecundity of E. nanum cushions at low density was consistent with reduced intraspecific competition for pollinators and might also represent a beneficial effect of highly outbred seeds as brought about by more long-distance pollinator flights under low-density conditions.  相似文献   

4.
 Flower development, pollination and breeding system of the high alpine cushion plant, Eritrichium nanum (Boraginaceae), were investigated in nine populations from the European Alps at altitudes of 2700 m–3200 m. Peak flowering period lasts longer than a month, from mid-June to the end of July. In contrast to statements in the literature that flowers are protogynous and nutlets remain in their calyx until spring we found a distinct protandry and nutlets being dispersed before mid-September. Various insects from 12 families, but mostly Diptera, frequently visited E. nanum flowers, with flies from the families Anthomyiidae and Muscidae being the predominant visitors. Under optimal conditions (max. solar radiation, min. wind force), visitation rates of 200 simultaneously observed flowers reached 32.5–46.7 insects per hour, i.e. 0.16–0.24 insects per flower per hour. However, the commonly observed Anthomyiidae and Muscidae clearly preferred the white-yellowish flowers of Saxifraga exarata and Saxifraga bryoides which are abundant at E. nanum sites and which are certainly also pollinated by species of these two fly families. The flowers of these Saxifraga species offer plenty of nectar and may compete for pollinators with E. nanum, when they are flowering in its proximity. However, various other insects like Pontia callidice and Psodos sp. (Lepidoptera) as well as Andrena sp. (Hymenoptera) and especially Eristalis tenax and closely related hoverflies showed a higher degree of flower constancy to E. nanum, often flying from a blue Eritrichium cushion to the next and hence causing outcrossing. The five fornices of E. nanum flowers which obstruct the tube containing stamens and nectar, are a feature which differs distinctly from the syndrome of fly-pollinated flowers with easily accessible nectar. Consequently pollination by flies in E. nanum seems to be caused mainly by the unfavorable ecological conditions at high altitudes, where flies are the most frequent insects. Bagging experiments showed that outcrossing and geitonogamy are the prevailing pollination modes, and autogamy, although possible, plays only a minor role. Received February 13, 2001 Accepted November 23, 2001  相似文献   

5.
Spectroscopy information (functional groups and semiquantitative data) by Fourier transform infrared (FTIR) spectroscopy of Spongiophyton Kräusel emend. Chaloner et al. is reported for the first time, in an attempt to identify spectroscopic patterns that would differentiate species of these taxa. A total of 33 specimens identified as S. lenticularis, S. nanum and S. minutissimum and preserved as compressions were analysed. They come from the same fossiliferous horizon of one outcrop situated in the uppermost Middle Devonian São Domingos Formation of the Paraná Basin in southern Brazil. The results reveal that functional groups in the 3000–2800 and 1800–700 cm?1 wavenumber regions are present in all specimens. Infrared‐derived ratios (CH2/CH3, Al/Ox, Ox1/Ox2, C=O cont., C=C cont., Al2 and Ar/Al) and types of kerogen led to a comparison of the morphological characteristics of the studied material and indicate that compressions of S. lenticularis, S. nanum and S. minutissimum contain different organic compounds. S. nanum and S. minutissimum show higher oxidation and lower aromaticity of its organic matter than S. lenticularis. Additionally, S. lenticularis shows low A‐factor values, suggesting a composition similar to type III kerogen, while S. nanum and S. minutissimum showed intermediate to high A‐factor values, suggesting a composition similar to type II kerogen. In conclusion, the chemical‐analytical techniques and statistical analysis (using PCA technique) reveal a closer taxonomic relationship between S. nanum and S. minutissimum than either has with S. lenticularis, supporting their taxonomic separation, previously proposed in the literature on the basis of morphological features. Lastly, the chemical signatures support the hypothesis that links these enigmatic fossils to a type of lichen or other early inland plant.  相似文献   

6.
7.
Eritrichium nanum 《Flora》2004,199(5):398-408
In 14 permanent plots at four distant sites in the European Alps life tables, cohorts and recruitment of Eritrichium nanum were studied during a period of 5 resp. 6 years. The germination rates were tested in the Botanical Institute of the University of Basel and besides the life tables of the plots at natural habitats we followed the early stages of development in pot cultures at the University Botanical Garden in Basel. Most of the seedlings of E. nanum emerged in spring, in the pot cultures as well as under natural conditions, a behavior which confirms general findings. But the germination rates (0–30%) were markedly low. The pot cultures show that some seeds are after 4 or 5 years still viable. Premature flowering in the second summer is a rather common behavior of E. nanum seedlings, which happened in all the cohorts observed during five years, partly up to 20% of the total of living plants in the corresponding plots. It is evident that life expectancy of E. nanum plants increase rapidly with rising size, to such a degree that cushions of only 10–20 cm2 surface have a survival chance of more than 70%, those of 20–30 cm2 even of more than 95% during a period of 5 years. But it has to be mentioned that juvenile plants are not growing parallel to their lifetime, many of them persist during several years in the size categories I/II (0–5 cm2), while others suddenly arise from category I to III (–10 cm2) or even IV (–20 cm2), what is mostly caused by joining, a specific type of safe site strategy. Though not obligatory, juvenile plants growing close together, often add their sizes to form one larger cushion, which was found to be particularly advantageous for recruitment. This is obviously a primary strategy of E. nanum and favors, especially on bare ground, the survival of its descendants which was found higher than expected (average of 26% after 5 years’ growth at natural habitats). Focusing on the whole life cycle of E. nanum, the present studies show constraints in pollination, a small seed production and low germination rates to be well compensated by the high survivorship and successful recruitment of the seedlings.  相似文献   

8.
The first European case of swine infection byMicrosporum nanum is reported. The infected pig came from a farm in the Emilia-Romagna region of Italy. European records of human and lower animal infections by this fungus and soil isolation records are discussed.  相似文献   

9.
K. G. Mukerji 《Mycopathologia》1970,42(3-4):277-280
Three coprophilous ascomycetes have been reported for the first time from India. They arePreussia isomera Cain,Gelasinospora tetraspora Dowding andPodospora absimilis Cain.  相似文献   

10.
V. P. Sahni 《Mycopathologia》1965,27(3-4):342-356
Summary In the present paper twelve fungi belonging to the form class Deuteromycetes are described from Jabalpur (M.P.) India. Among these the new host records areMonochaetia carissae Munjal &Kapoor onCarissa spinarum L.,Pestalotia neglecta Thuem. onAtylosia scarabaeoides,Benth.,Pestalotia japonica Syd. onCelastrus paniculatus Willd.,Pestalotia theae Sawada var.minor Stey. onButea monosperma (Lam.)Kuntze,Pestalotia versicolor Speg. onBuchanania lanzan Spreng.,Colletotrichum dematium (Pers. exFr.)Grove onAmorphophallus sp.,Colletotrichum lindemuthianum (Sacc. &Mag.)Bri. &Cav. onCassia tora L.,Coniella diplodiella (Speg.)Petrak &Syd. on.Anogeissus latifolia Wall.,Hendersonula toruloidea Nattrass onPhilodendron bipinnatifidum Schott. andMyrothecium roridum Tode exFr. onCasearia tomentosa roxb. The above fungi include two species (Pestalotia neglecta Thuem. andPestalotia theae Sawada var.minor Stey.) which have been described for the first time from this country.Sphaeropsis tumefasciens Hedges onCitrus medica L. var.acida L. is a new record from this state; andExcipularia narsapurensis Subramanian, also a new record from the state, is reported for the first time on a named host.  相似文献   

11.
In a survey of the genusHybanthus in Brazil, it was found thatIonidium nanum A. St.-Hil. should be considered distinct fromHybanthus albus (A. St.-Hil.) Baill., based on characteristics of indument, habit and nectariferous appendages, and also habitat and geographical distribution. A new combination ofI. nanum withinHybanthus is therefore proposed.  相似文献   

12.
Summary Two species of fungi,Tryblidiella rufula (Spreng.)Sacc. andTrabutia butleri Theiss &Syd. have been figured and described for the first time from Orissa. The former was found growing on dead twigs ofCitrus aurantifolia (Christm.)Swingle and onCitrus sp. and the latter on living leaves ofFicus religiosa L.  相似文献   

13.
Summary Several forest fungi, primarily species that occur in Mississippi, are discussed, and three species are described as new. These includeBotryobasidium (subgenusBrevibasidium)croceum Lentz,Tharoopama mississippiensis Lentz, andHarpographium zonatum Lentz.Dactylium leptosporum (Sacc.)Lentz is recognized as a distinct species, rather than as a subspecies ofD. dendroides Fr. Allescheriella crocea (Mont.)Hughes,D. leptosporum andMelanographium cookei M. B. Ellis are reported from Mississippi for the first time. Attention is called to the fact thatM. citri (Fragoso &Ciferri)M. B. Ellis apparently has not previously been reported from the United States, although a specimen from Florida is in the National Fungus Collections.B. croceum evidently represents the basidiophorous stage ofA. crocea.  相似文献   

14.
V. P. Sahni 《Mycopathologia》1964,23(4):328-338
Summary The present paper describes nine ectoparasitic foliicolous fungi from Jabalpur (M.P.) India. These include four new species viz.Asterina woodfordiae Sahni onWoodfordia fruticosa (L.)Kurz.,Schiffnerula fici Sahni, onFicus infectoria Roxb.,Sarcihella fumosus Sahni onAegle marmelos Corr. andSarcinella odinae Sahni onOdina wodier Roxb.,Acremoniella sarcinellae Pat. &Har.,Fumago vagans Pers.,Stigmella palawanensis Syd. andSchiffnerula cassiae are new fungus records for this country.Mitteriella zizyphina Syd. has been recorded onZizyphus xylopyra Willd., for the first time from this state.Z. xylopyra is a new host record forM. zizyphina.  相似文献   

15.
16.
Recently, we reported on the construction of a whole-cell biotransformation system in Escherichia coli for the production of d-mannitol from d-fructose (Kaup B, Bringer-Meyer S, Sahm H (2004) Metabolic engineering of Escherichia coli: construction of an efficient biocatalyst for d-mannitol formation in a whole-cell biotransformation. Appl Microbiol Biotechnol 64:333–339). Supplementation of this strain with extracellular glucose isomerase resulted in the formation of 800 mM d-mannitol from 1,000 mM d-glucose. Co-expression of the xylA gene of E. coli in the biotransformation strain resulted in a d-mannitol concentration of 420 mM from 1,000 mM d-glucose. This is the first example of conversion of d-glucose to d-mannitol with direct coupling of a glucose isomerase to the biotransformation system.  相似文献   

17.
Chromosome numbers are reported for 15 taxa ofHieracium sect.Alpina (Griseb.)Gremli from Central and eastern Europe (Austria, the Czech Republic, Poland, Romania, Slovakia, Ukraine). The mode of reproduction was also studied for some of the taxa. For the first time the chromosome counts of 5 taxa from theHieracium rohacsense group are given:H. rohacsense Kit. (the West Carpathians),H. ratezaticum (Nyár. etZahn)Mráz (the South Carpathians) and a still unnamed taxon of theH. rohacsense group from Mt. Pop Ivan (the East Carpathians) are tetraploid (2n=36);H. rauzense Murr (the Eastern Alps) andH. borsanum Mráz (the East Carpathians) are triploid (2n=27).H. krivanense (Woł. etZahn)Schljakov (the West Carpathians) is tetraploid,H. brevipiliferum Mráz (the South Carpathians) is triploid; these are the first karyological reports of both taxa belonging to theH. fritzei group. The tetraploid chromosome number was revealed for the first time in an unnamed taxon of theH. nigrescens group from the West Carpathians, and inH. nigrescens subsp.koprovanum Rech. f. etZahn. InH. alpinum L. s.str. triploid (2n=27) populations from the West Carpathians and diploid populations (2n=18) from the East Carpathians were confirmed. ForH. halleri Vill. (theH. alpinum group, the West Carpathians) andH. nigrescens Willd. (the West Sudeten), the numbers 2n=27 and 2n=36, respectively were found, which is in accordance with previous data. The triploid level (2n=27) forH. pinetophilum (theH. fritzei group) and the tetraploid level (2n=36) forH. stygium Uechtr. (theH. chlorocephalum group) both from the West Carpathians were confirmed. One new species, onenomen novum and one new combination at the level of species are published in this paper.  相似文献   

18.
Duan J  Zhang Q  Zhao H  Du J  Bai F  Bai G 《Biotechnology letters》2012,34(6):1101-1106
An isolate of a Pseudomonas sp. uses the l-NCC (N-carbamoyl-l-cysteine) pathway to convert dl-2-amino-Δ2-thiazoline-4-carboxylic acid (dl-ATC) to l-cysteine. Genes encoding ATC racemase (AtcA), l-ATC hydrolase (AtcB) and l-NCC amidohydrolase (AtcC), involved in this pathway, were cloned from the Pseudomonas sp. and expressed in Escherichia coli BL21 via pET-28a(+). The resulting enzymes were purified, their functions identified, and their biochemical properties are described. In vitro catalysis experiments, using these enzymes, revealed that the bioconversion rate of l-cysteine from dl-ATC in the presence of AtcA was more efficient than in the absence of AtcA. This is the first report describing simultaneous cloning and expression of atcA, atcB and atcC and characterization of their enzymes for l-cysteine production from dl-ATC via the l-NCC pathway, enabling the complete l-NCC pathway to be elucidated.  相似文献   

19.
A taxonomic reevaluation of two little-knownBrimeura taxa,B. fontqueri (Pau)Speta andB. duvigneaudii (L. Llorens)Rosselló et al., has been made.Brimeura fontqueri, described from the Iberian peninsula, has been put into synonymy ofB. amethystina (L.)Salisb., since it could not be distinguished on morphological, anatomical or cytogenetic grounds.Brimeura duvigneaudii, from the Balearic Islands, is closely related toB. amethystina and has 2n=28 chromosomes. It differs from the latter by its naked bulbs lacking dark cataphylls, and its narrower leaves and whitish corollas. Accessory chromosomes are reported for the first time in the genus. Karyological instability (with chromosome numbers ranging from 2n=28 to 42) is reported for a population ofB. fastigiata (Viv.)Chouard. A key to the recognized taxa ofBrimeura is provided.  相似文献   

20.
Two sequences of about 10.5 m originating from a peat bog in Romania were analysed for pollen (202 and 127 pollen spectra). The vegetation history, supported by 24 14C dates is described since the Late Glacial. At the onset of the Holocene Ulmus first appears, together with Betula. Among the main components of the Quercetum mixtum (Quercus, Fraxinus, Tilia, Corylus) that became established almost simultaneously by around 9000 B.P., Quercus frequencies rarely exceed 10%. The local establishment of Carpinus is about 6000 b.p. Its maximum occurred between 4500 and 3000 b.p. Fagus pollen is regularly recorded since 8000 b.p. Its absolute dominance tooks place at about 3000 b.p. Picea pollen is present since the Late Glacial. The first indications of human activities appear at around 6500 b.p.  相似文献   

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