摘要:

ABSTRACTA disjunctor is a spindle- or needle-like crystalline organelle unique to the majority ofMoniliniaspp. It develops through the pores of septal lamellae of adjacent maturing conidia. At each end of a disjunctor one or two telomeric knobs are observed. The disjunctors are variable in size (3–10×0.25-2.5μm) and ornamentation, depending upon the species. In many taxa ornamentation consists of more or less concentric ridges which represent coalesced individual warts, some of which remain attached to the corresponding discrete warts on the septal lamellae. The development of the disjunctor inMonilinia vaccinii-corymbosi, a pathogen of blueberries, is described in detail and compared with that of several otherMoniliniaspp. A list of the species with or without disjunctors is provided.

ISSN:0027-5514    

DOI:10.1080/00275514.1988.12025597

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

ABSTRACTBuffer-soluble mycelial proteins of six species ofPythiumwere compared by isoelectric focusing. Species studied includedP. aphanidermatum(P.a.),P. deliense(P.de.),P. myriotylum(P.m.),P. dissotocum(P.di.),P. violae(P.v.),P. ultimumvar.ultimum(P.u.u.) andP.u.var.sporangiferum(P.u.s.).Each species had one or more distinct bands, in addition to many common bands of protein, when focused between pH 4–8. A higher concentration of proteins focused in the acidic region of broad pH range gels. Major protein bands were detected with Coomassie stain. Silver staining increased detection of proteins in low concentration (minor bands) in acidic, neutral, and alkaline regions. Other distinct bands of protein were identified for each species when protein samples were further resolved by focusing in the acidic region (pH 3–6). Several isolates each ofP.a., P.u., andP.de., collected from various regions of North America, produced consistent protein banding patterns with minor variations. Although banding patterns ofP. aphanidermatumdiffered slightly when isolates were cultured on different media, protein patterns were still specifically identifiable. No differences in protein bands were observed betweenP.u.u.andP.u.s.The utility of isoelectric focusing for the differentiation of species ofPythiumis discussed.

ISSN:0027-5514    

DOI:10.1080/00275514.1988.12025598

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

ABSTRACTThe herbicide Sandoz 6706 (metflurazon) inhibits carotene biosynthesis and allows photobleaching of chlorophyll in light-grown green plants. To explore its effects in non-photosynthetic organisms, the influence of metflurazon on pigmentation of nine soil-inhabiting fungi, representing a broad taxonomic spectrum, was investigated. Metflurazon treatment reduced observable intensity of pigmentation in many of these fungi. In the yeastRhodotorula glutinis, herbicide treatment decreasedβ-carotene concentrations and increased the levels of phytoene, a colorless precursor ofβ-carotene. These results suggest that, in this yeast, metflurazon either inhibits a phytoene dehydrogenase or prevents end-product inhibition of phytoene production. Thus, one mechanism of action of the herbicide inR. glutinisis similar to that proposed for some photosynthetic organisms.

ISSN:0027-5514    

DOI:10.1080/00275514.1988.12025599

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

ABSTRACTA range of ascospore morphologies was observed in several collections of perithecia ofGibberella zeaeonZea mays.In general, the basic ascospore condition appeared to be a spore with four, approximately equal-sized uninucleate cells. Three-celled ascospores sometimes occurred, one cell of which was binucleate and tended to be about twice the size of the others. In two-celled ascospores, both cells tended to be binucleate, while single-celled ascospores were binucleate. Ascospores of all four classes germinated on water agar with no changes in septation. Germination of three- and four-celled ascospores was almost exclusively from one or both end cells, while two-celled spores germinated from one or both cells. Taxonomic and evolutionary implications of these findings are discussed.

ISSN:0027-5514    

DOI:10.1080/00275514.1988.12025600

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

ABSTRACTPistillaria johnsoniiis transferred to the anamorph genusAkanthomycesand redescribed and illustrated from herbarium specimens and cultures. The species produces white indeterminate synnemata with phialidic conidiogenous cells and catenate ameroconidia, and occurs on decaying leaves and herbaceous litter, often in association with species ofBotryosporium.

ISSN:0027-5514    

DOI:10.1080/00275514.1988.12025601

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

ABSTRACTIsozyme analysis of extracellular laccases (ECLs) ofAgaricusspp. on Polyacrylamide gels revealed patterns of activity which were dissimilar between species but largely invariant within species. In many species the various ECL electromorphs in the culture medium appeared and disappeared, or became more or less abundant, in a temporal sequence of several weeks duration. There is a tendency for some ECL bands to increase in mobility by 1–2 percent as cultures age. Electrophoretic comparison of ECLs appears to be a promising method contributing toward systematic resolution and phylogenetic reconstruction inAgaricus.

ISSN:0027-5514    

DOI:10.1080/00275514.1988.12025602

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

ABSTRACTThe generic nameDactuliochaetais established to accommodatePyrenochaeta glycines, the causal agent of red leaf blotch of soybeans and its synanamorphDactuliophora glycines.The fungus is redescribed and illustrated from isolates originating from sclerotia onNeonotonia wightiior soybean (Glycine max) leaves or that were sieved from soil in Zambia, Africa. The genus is characterized by setose sclerotia which germinate to form mycelium and then setose pycnidia and/or pycnidia and sclerotia on their surfaces. The inner pycnidial walls are lined with ampulliform to lageniform, phialidic conidiogenous cells that often are periclinally thickened at the conidiogenous locus and bear uninucleate, hyaline conidia.

ISSN:0027-5514    

DOI:10.1080/00275514.1988.12025603

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

ABSTRACTPatterns of calcium oxalate crystal development on sporangiophores and sporangia ofGilbertella persicariaare a consistent feature of this fungus when grown on a variety of standard mycological media. When grown on a liquid synthetic medium consisting of dextrose and salts, initial growth of the fungus and production of calcium oxalate crystals mimics growth on standard solid media. Soon, however, crystal production becomes aberrant, then ceases. Concomitant with the change in crystal morphology, growth of aerial portions of the colony increases dramatically. Normal colony morphology and crystal production are maintained when calcium salts are added to the synthetic medium. Significantly more fungal dry weight is produced on the synthetic medium when no calcium is added.Data gathered suggest that: 1) mineralized deposits may provide structural support; 2) early production of crystal-bearing sporangia lowers calcium concentrations in the medium sufficiently to alter and eventually stop calcium oxalate crystal production; 3) calcium may inhibit growth; 4) calcium oxalate crystal production inG. persicariamay regulate environmental calcium concentrations.

ISSN:0027-5514    

DOI:10.1080/00275514.1988.12025604

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

ABSTRACTTwo triazoles, cyproconazole and propiconazole, and the imidazole, prochloraz, all commercially available fungicides that inhibit 14α-demethylation during sterol synthesis, were applied to a cholesterol-producing fungus,Allomyces macrogynus, during growth phase. Concentrations of the above inhibitors 1/100-1/500 of the EC50concentrations needed for inhibition of vegetative growth, caused failure of sporangia to cleave normally and produce uniformly sized, uniflagellate zoospores. Instead, dependent upon the concentration of fungicide used, motile cells were uniflagellate, biflagellate, triflagellate or multiflagellate with the number of nuclei corresponding to the number of flagella. The fungicides were only effective if they were present during the growth phase and impairment of cleavage could not be overcome by adding cholesterol to the discharge medium. Observations were based on light and electron microscope observations. Multinucleate cells with more than one flagellum germinated to produce normal thalli when plated on agar lacking the fungicides. The basis of the interference with cleavage is discussed.

ISSN:0027-5514    

DOI:10.1080/00275514.1988.12025605

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1988.12025606

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor