摘要:

Volatiles emanating from fungi, bacteria, germinating or killed seeds, and nonsterile or sterile natural substrates (decaying wood, partially decayed oak duff, and garden soil) were tested for their effects onPyronema domesticum, a pyrophilous discomycete. Mycelial growth was strongly stimulated by volatiles fromSchizophyllum communeand inhibited by volatiles fromStreptomyces griseusbut otherwise was generally unaffected. Volatiles fromChaetomium globosum, a secondPyronema domesticumculture,Trichophea abundans, orTrichoderma viridehad little or no effect on numbers of apothecia produced. Fewer apothecia formed with volatiles fromBacillus subtilis,Cyathus stercoreus,Dipodascopsis uninucleatus,Poronia aedipus,Proteus vulgaris,Micrococcus luteus, andStreptomyces griseus. Volatiles from all bacteria andDipodascopsis uninucleatusimpaired development of the ascogenous system. Elongated asci without ascospores formed in the presence ofProteus vulgaris. Apothecia did not form in the presence of volatiles fromSordaria fimicola,Schizophyllum commune,Rhizopus nigricans, germinating seeds, nonsterile wood, or charred duff. Volatiles from autoclaved seeds, nonsterile or autoclaved soil or duff, wood ashes, and sterile wood are strongly inhibitory for apothecial development and permitted only a few apothecia to form.

ISSN:0008-4026    

DOI:10.1139/b88-031

出版商:NRC Research Press    

年代:1988

数据来源: NRC

摘要:

Leaves ofNicotiana tabacumL. cv. Xanthi-nc,Nicotiana clevelandiiGray,Nicotiana rusticaL., andChenopodium amaranticolorCoste & Reyn. were infected with the U1strain of tobacco mosaic virus and leaves ofNicotiana sylvestrisSpeg. & Comes andSolanum tuberosumL. cv. Kennebec were infected with the U2strain. After 10 days, pathogenesis-related (PR) proteins from intercellular fluid extracts were separated by nondenaturing polyacrylamide gel electrophoretic (PAGE) systems for acidic or basic proteins, sometimes followed by denaturating PAGE with lithium dodecyl sulfate. PR proteins were then transferred to nitrocellulose to determine serological relationships. Using an antiserum directed against native PR proteinb4from 'Xanthi-nc' tobacco, serologically reacting acidic PR proteins could be detected in all plant species. Except for potato, related basic PR proteins were also found in all species. Serological relationships were further studied between 'Xanthi-nc' tobacco and 'Kennebec' potato PR proteins separated in PAGE gels under native conditions. Potato basic PR proteins withRfs of 0.83, 0.85, and 1.00 were serologically related to tobacco acidic PR proteins of theb4group. Potato acidic PR proteins withRfs of 0.56, 0.58, 0.61, and 0.64 were related to tobacco acidic PR proteins of theb4group. Potato acidic PR proteins withRfs of 0.18 and 0.21 reacted with an antiserum against tobacco PR proteinb9. Three potato acidic peroxidases were also serologically related to tobacco peroxidasesb6aandb7a. Analysis with denaturing PAGE systems gave results difficult to interpret because bovine carbonic anhydrase, for example, cross-reacted with an antiserum against tobacco PR proteinb4. A similar relationship could not be detected in PAGE systems under native conditions.

ISSN:0008-4026    

DOI:10.1139/b88-032

出版商:NRC Research Press    

年代:1988

数据来源: NRC

摘要:

Streptomycin sulphate prevented infection of sunflower seedlings by three races of the downy mildew pathogenPlasmopara halstedii(Farl.) Berlese et de Toni. It inhibited emergence of zoospores from zoosporangia and at high concentrations (500 ppm) was phytotoxic. Affected seedlings were stunted and chlorotic. Penicillin had no observable effect on infection or on appearance of the seedlings.

ISSN:0008-4026    

DOI:10.1139/b88-033

出版商:NRC Research Press    

年代:1988

数据来源: NRC

摘要:

The plumule in rosette plants showing the phenomenon of "pseudomonocotyly" remains in a quiescent stage at the base of the cotyledonary tube, and this quiescent stage appears to be due to the inhibitory influence of the cotyledons. This correlative inhibition in which the development of the embryonic apical region is influenced by the cotyledon may be an important survival adaptation in alpine rosettes.

ISSN:0008-4026    

DOI:10.1139/b88-034

出版商:NRC Research Press    

年代:1988

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b88-036

出版商:NRC Research Press    

年代:1988

数据来源: NRC