ISSN:0027-5514    

DOI:10.1080/00275514.1980.12021262

出版商:Taylor&Francis    

年代:1980

数据来源: Taylor

摘要:

SUMMARYAmino acids produced in vitro by the ectomycorrhizal fungusPisolithus tinctoriuswere analyzed by gas-liquid chromatography. Glutamic acid was the major component (21%) of the amino acids in the total and bound pools during the exponential phase of growth. Alanine was the major component (35%) in the free pool during the acceleration phase and in the early days of the exponential phase (33%), but subsequently decreased rapidly. Arginine, an ornithine-cycle intermediate, was present in substantial amounts (~7) in the total and bound pools during the exponential phase, but decreased in the free pool during the exponential phase. Citrulline and ornithine, also ornithine-cycle intermediates, were present in all fractions. The pattern of free ammonia production suggested urease activity resulting from the reduction of arginine. The pattern of amino-acid synthesis exhibited byP. tinctoriussuggests that alanine as well as glutamic acid may be a route by which amino compounds are formed from inorganic nitrogen. The presence of arginine, citrulline, ornithine, and free ammonia in the free pool may be an indication that the ornithine cycle is operative in this fungus. It is not possible to conclude whether the presence of small or large concentrations of ornithine-cycle intermediates, especially arginine, in ectomycorrhizal fungi is critical for the enhancement of nitrogen uptake in ectomycorrhizae.

ISSN:0027-5514    

DOI:10.1080/00275514.1980.12021263

出版商:Taylor&Francis    

年代:1980

数据来源: Taylor

摘要:

SUMMARYFusarium moniliformewas isolated from between 43 and 68% of symptomless maize kernels stored for 10 to 15 mo (aged kernels) and from between 36 and 78% of freshly harvested kernels. The fungus was present in healthy seedlings grown from aged and fresh kernels in the field 40 da after planting. From these field-grown seedlingsF. moniliformewas readily isolated from the growing point, crown and root of 10-da-old seedlings grown from both aged and fresh kernels and from the crown and root of 20-da-old seedlings grown from aged kernels. At 40 da after planting the fungus was isolated mostly from the roots. The evidence obtained indicates thatF. moniliformecan survive in healthy maize kernels for up to 15 mo and can be isolated from healthy roots of 40-da-old plants. Maize roots could be one important source ofF. moniliformeinoculum for stalk-rot infection in mature plants late in the growing season.

ISSN:0027-5514    

DOI:10.1080/00275514.1980.12021264

出版商:Taylor&Francis    

年代:1980

数据来源: Taylor

摘要:

SUMMARYOospore morphology and germination were studied using 17 isolates representing three morphological forms (MF) ofPhytophthora palmivorafrom cacao. Oospore production was most abundant on carrot agar. The shapes of gametangia and oospores produced in crosses between different MF isolates were more variable than those produced when the mated isolates were of the same MF. Mating between the MFs produced oospores with varying capacities for germination. Germination of oospores increased with increasing age. Pretreatment for 1 wk at 12 and at 30 C stimulated germination two-fold over oospores pretreated at 21 C. F1progeny from various matings within and between MFs showed differences in colonial morphology, production and morphology of sporangia, and mating type. However, the lengths of the sporangial stalks of F1progeny from germinated oospores derived from either crosses within or between MFs were all similar to the parental types. Two modes of oospore germination were defined; in one mode, which has not been previously reported, oospores germinated within 24 h by producing many germ tubes, each with a germ-sporangium deciduous with a long stalk. In the other mode, more typical ofP. palmivora, one germ tube formed a single, papillate, nondeciduous sporangium.

ISSN:0027-5514    

DOI:10.1080/00275514.1980.12021265

出版商:Taylor&Francis    

年代:1980

数据来源: Taylor

摘要:

SUMMARYThree new species are described.Flagelloscypha tetraedrisporais very different from all known species because of tetrahedrical spores and urniform basidia. The similarities betweenF. oblongispora, F. flagellata, F. parasiticaandF. minutissimaas well as those betweenF. fusisporaandF. dextrinoideaare discussed.

ISSN:0027-5514    

DOI:10.1080/00275514.1980.12021266

出版商:Taylor&Francis    

年代:1980

数据来源: Taylor

摘要:

SUMMARYSerial thin sections through entire pachytene nuclei ofSorosphaera veronicaewere analyzed to determine the number of synaptonemal complexes (SCs) per nucleus. The haploid number of chromosomes revealed by this method is 33.

ISSN:0027-5514    

DOI:10.1080/00275514.1980.12021267

出版商:Taylor&Francis    

年代:1980

数据来源: Taylor

摘要:

SUMMARYAirborne basidiospores released from field-produced basidiocarps ofCryptoporus volvatuswere collected by placing a funnel, equipped with a collection vial, below each of seven developing basidiocarps. Spores collected in the vials were counted every 7 to 11 da until spore release ceased (average 71 da). Spores released per basidiocarp averaged 2.5×109(4.0×108/cm2of pore surface), comparable to spore production by other polypores whose spores are wind disseminated. Spore-release patterns were not affected by rainfall. The unique subtending volva, long considered an adaptation for insect dispersal, appears to be a xerophytic adaptation which protects the hymenophore from desiccation. The volva allows production of airborne spores during the periods of low rainfall and relative humidity often associated with bark-beetle flights in the areas of western North America where this fungus is most common.

ISSN:0027-5514    

DOI:10.1080/00275514.1980.12021268

出版商:Taylor&Francis    

年代:1980

数据来源: Taylor

摘要:

SUMMARYInvestigations on an isolate ofBipolarissp. demonstrate that this fungus displays autoinhibition of conidium germination. Filtrates from 3–7-da-old agitated liquid cultures permitted germination in less than 5% of the conidia tested. Addition of nutrients to 5-da filtrates failed to overcome inhibition completely. The inhibitory activity of filtrates was unchanged by freezing, autoclaving, or concentration. An inverted-culture bioassay showed that the time course for the production of inhibitory factors in agar cultures was similar to that seen in liquid cultures, and that comparable patterns were observed when different carbon and nitrogen sources were tested. The germination of conidia of six Deuteromycetes and the sporangiospores of one zygomycete was delayed or inhibited when incubated on inverted-agar cultures ofBipolaris. Bipolarisconidia incubated on the upper surface of an actively growing colony yielded 3–5% germination at the center of the colony and 95–99% germination over the colony margin and uncolonized medium. Conidia incubated at densities greater than 10×102spores/ml exhibited decreased germination percentages compared to more dilute suspensions. Growth of germ tubes was not as susceptible to the action of inhibitory filtrates as was conidium germination, and it was shown that conidia which had passed the latent period in germination were no longer susceptible to the inhibitor.

ISSN:0027-5514    

DOI:10.1080/00275514.1980.12021269

出版商:Taylor&Francis    

年代:1980

数据来源: Taylor

摘要:

SUMMARYThe taxonomy and morphology of the myxomycete genusEchinosteliumare presented, along with a key to the species. Members of this genus have minute, stipitate sporangia, and they are often encountered on the bark surface of living trees or dead plant materials in moist-chamber culture. Four new species,E. apitectum, E. brooksii, E. corynophorum, andE. paucifilumare described. Thirteen species are recognized, and detailed descriptions of each are provided. Illustrations of 12 of these species are included.

ISSN:0027-5514    

DOI:10.1080/00275514.1980.12021270

出版商:Taylor&Francis    

年代:1980

数据来源: Taylor

摘要:

SUMMARYBuffer-soluble, nonspecific protein and enzyme patterns from polyacryl-amide-disc-gel electrophoresis were compared for three morphological forms (MF) and one“other type”ofPhytophthora palmivorafrom cacao (Theobroma cacao) and for the type cultures ofP. capsiciandP. cinnamomi.Comparison of the total protein patterns indicated that each MF produced consistent major bands distinctly different from those of other MFs. Clear differences between MFs were also obtained in esterase patterns, but there were fewer differences in their peroxidase patterns. Protein and enzyme patterns from the type cultures ofP. capsiciandP. cinnamomiwere strikingly different from each other and from those of most of the cacao isolates; some similarities were noted between MF4 andP. capsici.These results and other morphological studies indicate that the three MFs ofP. palmivoraare sufficiently different to be classified as three distinct species.

ISSN:0027-5514    

DOI:10.1080/00275514.1980.12021271

出版商:Taylor&Francis    

年代:1980

数据来源: Taylor