摘要:

SUMMARYEleven taxa with“muscae-type”conidia (broadly ellipsoidal with a papillate apex and flattened base) have been named and described in the genusEntomophthora.Only five (E. culicis, E. erupta, E. muscae, E. planchoniana, andE. weberi) are considered valid species and a key for their identification, based on their morphology and hosts is provided. The remaining six are considered to be synonyms of earlier described species:E. rimosawithE. culicis;E. pelliculosa, E. scatophagae, andE. syrphiwithE. muscae; andE. chromaphidisandE. ferrugineawithE. planchoniana.

ISSN:0027-5514    

DOI:10.1080/00275514.1976.12019881

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYA coiled, septate, multinucleate ascogonium or its parent hypha produces branches that enfold the ascogonium and produce a small ball of cells with the ascogonium in the center. The outer layers of cells differentiate into the perithecial wall. As the radius of the perithecium doubles, the number of wall cells increases two- to threefold per section and each cell expands sufficiently in volume to maintain the spherical shape of the perithecium. Plec- tenchyma cells of the centrum produce paraphyses which grow upward into a subapical cavity that is present before the paraphyses originate. Above the cavity a dome-shaped region of meristematic cells produces the neck, ostiole, and periphyses. The ascogonium does not increase in size when the perithecium enlarges. Ascogenous hyphae develop from the ascogonium after the neck and ostiole and paraphyses have begun to form. Terminal branches of ascogenous hyphae produce croziers, which in turn produce asci. Cytology of the ascus is much like that in other pyrenomycetes and includes a diffuse diplotene stage. Spores are initially uninucleate, later binucleate. The fungus is homothallic. The haploid chromosome number is seven.

ISSN:0027-5514    

DOI:10.1080/00275514.1976.12019882

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYAn isolate labelled K3-17 presenting the general features ofEmbellisia(Hyphomycetes, Dematiaceae) was obtained in 1972 from littoral sea water in Kotor Bay, South Adriatic. As in other species ofEmbellisia, K3-17 showed a marked tendency to form chlamydospores but it differed from them in the form of its conidia. In the fungus from the Adriatic 78–80% of the conidia were ovoid didymospores, 11.0×9.0μm, the nutrient media and the age of the cultures not contributing to any significant variation. Because of this feature the nameEmbellisia didymosporais proposed for the new taxon. The optimal temperature for growth was about 26 C.

ISSN:0027-5514    

DOI:10.1080/00275514.1976.12019883

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYThe first documented infection of a human being bySaksenaea vasiformisis described. Identification problems are discussed that stem from the failure of this zygomycete to sporulate on the primary isolation media used in medical mycology. The etiology of zygomycosis is critically reviewed and 10 species of zygomycetes classified in two orders and 6 genera are considered to be well authenticated as disease agents of humans.

ISSN:0027-5514    

DOI:10.1080/00275514.1976.12019884

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYMeasurement of voltages associated with sporulating maize leaf lesions revealed electrical charges that appeared to relate to violent liberation of conidia. Under precisely controlled conditions (relative humidity, temperature, light and air flow) maize leaf lesions became electrically charged in saturated air. Violent release of conidia triggered by either decreasing the relative humidity (RH), increasing the RH or exposing specimens to red- infrared radiation, was accompanied by significant voltage changes. Similar electrical changes were associated with healthy maize leaves growing under greenhouse conditions. On the basis of these experiments and other evidence, it is proposed that violent liberation of spores involves an exogenous surface electrical phenomenon whereby spores, sporophores and surrounding surfaces become charged (like charges) during periods of high humidity and this initiates an electrostatic repulsion between spore and sporophore. Lowering of the RH causes the charge to become static and also causes a weakening of the juncture between spore and sporophore. When the anatomical bond is sufficiently weakened the juncture breaks and the electrostatic force propels the spore into the air. Surface charges appear to originate mainly from the surface electrical phenomena associated with evaporation and condensation of water, and also under certain conditions from rain. An exogenous electrostatic mechanism should apply to all fungi having exposed nonmucilaginous spores (conidia, sporangia and basidiospores) borne on sporophores with a constriction between spore and sporophore, or between spores when in chains.

ISSN:0027-5514    

DOI:10.1080/00275514.1976.12019885

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYCellulin, the unique chitin-glucan granules found in leptomitalean fungi, was investigated by cytochemical, interference contrast, ultraviolet fluorescence and electron microscopy. The concentric ring substructure, routinely observed by light microscopy observations of granules, was found to be present at the ultrastructural level. It was hypothesized that this concentricity was derived from alternating zones in which either chitin orβ-ghican was the predominant, but not necessarily exclusive, component. Electron microscopy demonstrated numerous cytoplasmic vesicles located on the granule perimeters or in close proximity. It was hypothesized that these vesicles deliver cellulin precursors and enzymes to the periphery of developing granules where the accretion of additional polysaccharide material occurs. No definitive observations were made demonstrating the nucleation of the granules.

ISSN:0027-5514    

DOI:10.1080/00275514.1976.12019886

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYPhialophora dermatitidiscells were grown at 37 C on Sabouraud-glucose agar for 1–35 da. At designated time intervals cell populations were characterized for endogenous respiration and fatty acid content. Young cells (1-da-old) were found to have a low level of endogenous respiration when starved in phosphate buffer. Older cell populations had increasingly higher levels of endogenous respiration. Using gas chromatography, fatty acid analysis of cells grown at 37 C for 1,5,14, and 35 da revealed little qualitative differences in major component fatty acids. The four most prominent fatty acids found were oleic acid (69–73%), palmitic acid (20–25%), palmitoleic acid (0.9-2.0%), and stearic acid (1.8-6.0%). Short chain fatty acids (C12, C14, C15) were detected. Acids greater than C18 appeared in increasing quantities in cells incubated at 37 C for 5 da or more. Quantitative measurements of major component fatty acids of 1-da-old cells were approximately 5.1% in comparison to 5-da-old cells (6.9%), 14-da-old cells (33.2%), and 35-da-old cells (31.1%). It is believed that these large quantities of fatty acids constitute the prominent lipid bodies observed in older cells and account for the higher levels of endogenous respiration ofP. dermatitidis.

ISSN:0027-5514    

DOI:10.1080/00275514.1976.12019887

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYGermination of spores ofGlomus mosseaeon agar media was inhibited by excess nutrient such as provided in standard Potato Dextrose or Nutrient Broth Agars, unless very low concentrations of the respective nutrients were supplied. Spores did not germinate well on relatively nutrient-free (leached) agar, or Noble agar. High levels of germination occurred on media containing 1 g/liter of nutrient broth or potato dextrose amended to BBL brand water agar (0.75%). Extracts made by dialysis of untreated agricultural soils and added to otherwise“nutrient-free”agar supported best germination, 85–100%. Apparently, the nutrients extractable or dialysable from 200 g of field soils per liter of medium are ideal for germination. Conversely, dialysates from air dried, autoclaved or chloropicrin-treated soil added to the water agar prevented germination. It is hypothesized that nutrients available subsequent to autoclaving, air-drying or fumigation are excessive and hence inhibitory. When an air-dried soil sample was moistened, incubated for five days, and then filtered, the nutrients extracted again supported excellent spore germination.

ISSN:0027-5514    

DOI:10.1080/00275514.1976.12019888

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYYeastlike cells ofPhialophora dermatitidiswere induced to form thick-walled, multicellular (sclerotic) bodies under very acidic culture conditions. Phase-contrast microscopy and conventional transmission electron microscopy of thin sections were used to demonstrate the development of these structures. Observations indicated that the multicellular bodies represented an intermediate vegetative growth form phenotypically arrested between the yeastlike and hyphal morphology. The suggestion is made that the acidic cultural conditions inhibited the event of bud emergence by the yeastlike cells without inhibiting the events of growth, nuclear division and cytokinesis.

ISSN:0027-5514    

DOI:10.1080/00275514.1976.12019889

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYAmylomycesis a monotypic genus containing the somewhat variable speciesA. rouxiiCalmette. Certain species ofChlamydomucorand Boedijn's speciesRhizopus chlamydosporusare synonyms. Strains vary from somewhat restricted sterile white colonies to light gray-brown colonies containing many abortive sporangia. All strains produce abundant chlamydo-spores. During growth in liquid media containing glucose as the carbon source, the glucose is exhausted during the first 3 da and lactic acid is formed that is used as a secondary carbon source after a short lag period. The pattern of utilization of sucrose, maltose, and glycerol by strains ofAmylomyces rouxiiandRhizopus oryzaesupports the morphological data that make these two genera distinct.

ISSN:0027-5514    

DOI:10.1080/00275514.1976.12019890

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor