ISSN:0027-5514    

DOI:10.1080/00275514.1979.12020984

出版商:Taylor&Francis    

年代:1979

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1979.12020985

出版商:Taylor&Francis    

年代:1979

数据来源: Taylor

摘要:

SUMMARYInability to compete directly with other members of the carbonicolous community is examined as a factor contributing to the stratification of fungal sporocarp appearance in a heterotrophic succession following prairie burning. Evidence is presented that late successional species of carbonicolous ascomycetes from a prairie burn are uniformly antagonistic to species appearing earlier in the sere. Rapidly developing species such asGelasinospora calospora, Podospora curvicolla, P. glutinans, andSordaria fimicolawere inhibited by diffusable substance(s) produced byPodospora pilosa, a slower-growing and later-sporulating form. Rate of colony growth was not always related to the order of appearance of post-fire ascomycetes. The authors suggest that the evolutionary outcome of interference competition among post-fire-ascomycete populations is a pattern of competitive hierarchy in which late-successional species are increasingly capable of dominating earlier-appearing species.

ISSN:0027-5514    

DOI:10.1080/00275514.1979.12020986

出版商:Taylor&Francis    

年代:1979

数据来源: Taylor

摘要:

SUMMARYThe influence of temperature on the abundance, developmental sequence, morphology, and size ofPhytophthora cinnamomisexual structures was studied in a cross between isolates of A1and A2mating types, and in stimulation by avocado-root extract of homothallic oospore production in single cultures of an A2isolate. Gametangia were formed from 9 to 33 C, and oospores from 12 to 30 C. The optimum temperatures for oospore production were 15 to 21 C in the cross and 18 to 24 C for homothallic production in root extract. Temperature did not significantly influence size of sexual structures, but did affect the rate of development and abundance. Nutrition greatly influenced the sexual stage: significant differences in size and abundance of sexual structures were observed using the same cross on different media. Oogonia and oospores produced homothallically in root extract and those from the cross on a synthetic medium were larger than those from the cross on four natural media. Comparisons of sexual-structure measurements for taxonomic purposes should be made between structures produced on the same medium.

ISSN:0027-5514    

DOI:10.1080/00275514.1979.12020987

出版商:Taylor&Francis    

年代:1979

数据来源: Taylor

摘要:

SUMMARYPlasmodium formation by mating was studied in cultures containing equal numbers of mating-compatible amoebae. A period of amoebal multiplication always preceded Plasmodium formation. When the inoculum varied from a total of 3×103to 1.6×105cells per culture, Plasmodium formation commenced when the total number of cells reached about 5×105per culture. When the inoculum included an excess of a third strain of amoebae that is unable to mate with the first two, mating commenced when the total number of matable cells reached only 1×105per culture. This effect of the third strain of amoebae was not brought about by their consumption of the bacteria used as food, since directly limiting the number of food bacteria did not cause earlier mating. When amoebae of the third strain were separated from the mating cells by paired 0.2μm Nuclepore filters, premature mating still occurred. Thus, as is the case with asexual Plasmodium formation, one or more extracellular factors appear to influence the time of onset of mating.

ISSN:0027-5514    

DOI:10.1080/00275514.1979.12020988

出版商:Taylor&Francis    

年代:1979

数据来源: Taylor

摘要:

SUMMARYA key, descriptions, and illustrations are provided for the type and two other species inScytinostromella.Two new combinations,S. humifaciensandS. nannfeldtiiare proposed andS. subasperisporumis removed toGloeocystidiellum.

ISSN:0027-5514    

DOI:10.1080/00275514.1979.12020989

出版商:Taylor&Francis    

年代:1979

数据来源: Taylor

摘要:

SUMMARYPilidiella quercicola, a coelomycete isolated from strawberry (FragariaXananassoDuch.) fruit, was determined to be identical with the pycnidial state ofSchizoparme straminea.Morphology, cultural characteristics, and cytology have been studied.

ISSN:0027-5514    

DOI:10.1080/00275514.1979.12020990

出版商:Taylor&Francis    

年代:1979

数据来源: Taylor

摘要:

SUMMARYPantomycin is a new antibiotic isolated from a group of antibiotics produced in fermentation cultures ofStreptomyces hygroscopicus.Pantomycin is a triad composed of carbohydrate, lipid, and polypeptide moieties and is obtained by a series of extractions from homogenized cells with organic solvents. It is purified finally by selective elution from a Sephadex gel column with 48% ethanol. The purified antibiotic exhibits antifungal activity against one animal and 73 plant pathogens. It also displayed antibacterial activity against nine plant and seven human pathogens and one saprophyte. In addition, pantomycin inhibited Newcastle disease virus, vesicular stomatitis virus, and vaccinia virus.

ISSN:0027-5514    

DOI:10.1080/00275514.1979.12020991

出版商:Taylor&Francis    

年代:1979

数据来源: Taylor

摘要:

SUMMARYA smooth-spored species ofBadhamia, formerly included inB. ovispora, is formally described and given the nameB. semiannulata. Badhamia semiannulatais characterized by the presence of a columella, free spores that are ovoid with a partial ring along one side, and its apparent restriction to straw, decaying leaves, and dung of herbivorous animals.Badhamia semiannulatawas grown on dung-extract agar from spore to spore and single-spore isolates yielding a phaneroplasmodium.

ISSN:0027-5514    

DOI:10.1080/00275514.1979.12020992

出版商:Taylor&Francis    

年代:1979

数据来源: Taylor

摘要:

SUMMARYThe processes leading up to and including plasmogamy are described in the heterothallic euascomyceteNectria haematococcavar.Cucurbitae.When conidia are placed on a block of agar lying on a compatible mycelium bearing protoperithecia a series of interactions ensue that lead to the fusion of a cell(s) of the conidium with a trichogyne(s) emanating from the protoperithecium. These interactions are explainable in terms of diffusible substances that coordinate the respective behaviors of the two partners in the following sequence: (1) In response to a substance(s) produced by the recipient mycelium the conidium changes in both form and function, i.e. it becomes sexually“activated.”(2) Such“activated”conidia redistribute the protoplasm among their several cells, form papillae, and secrete a substance that attracts the trichogynes which then grow towards these conidia. (3) Plasmogamy then takes place between individual cells of a conidium and a trichogyne.Interactions in which one or both of the partners carried thecand/ormmutant genes, both of which interfere with the sexual reaction, were also examined. In mixed cultures neither mutant's function was restored by the proximity of its normal allele. In the case of the m mutant it was subsequently found that the block imposed by this allele occurred after plasmogamy and hence the intercellular complementation that the mixed cultures were designed to detect would not be expected to occur. A more intimate, intracellular action is now posited for this mutant.

ISSN:0027-5514    

DOI:10.1080/00275514.1979.12020993

出版商:Taylor&Francis    

年代:1979

数据来源: Taylor