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1. |
EXPERIMENTS ON CHEMICAL CONTROL OF DAMPING-OFF INPINUS RESINOSAAIT. |
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Canadian Journal of Research,
Volume 20c,
Issue 12,
1942,
Page 559-571
L. P. V. Johnson,
G. M. Linton,
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摘要:
Results from a series of greenhouse and nursery experiments on the relative control of damping-off in red pine, afforded by a wide range of chemicals, brought out the following points: (1) Semesan solutions in concentrations of 1:100 to 1:150 applied as soil treatment gave consistently the best control in both greenhouse and nursery. (2) Red copper oxide suspension in concentrations of 1:250 to 1:500 applied as a soil treatment was also effective, particularly in the greenhouse. (3) Red copper oxide and zinc oxide dusts used as seed treatments gave effective control under greenhouse conditions. (4) In the greenhouse, combinations of seed and soil treatments failed to prove more effective than treatments applied separately, while under certain nursery conditions the combined treatments were significantly less effective. (5) Fungicides as a group generally proved more effective than acidifying agents such as sulphuric acid and aluminium sulphate. It appeared that the acidifying agents gave good control in seasons of normal rainfall, but were more or less ineffective in dry seasons, when relatively large quantities of slightly alkaline irrigation water were applied, or in wet seasons, when excessive percolation occurred. (6) Seedlings from two-year–old red pine seed of somewhat reduced vitality proved to be much more susceptible than those from one-year–old seed.White spruce was used in some of the preliminary experiments and proved to be much less susceptible than red pine, although very similar in response to the various treatments.
ISSN:1923-4287
DOI:10.1139/cjr42c-045
出版商:NRC Research Press
年代:1942
数据来源: NRC
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2. |
CONTRIBUTIONS TO A STUDY OF THE FUNGOUS FLORA OF NOVA SCOTIA: VI. PYRENOMYCETES |
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Canadian Journal of Research,
Volume 20c,
Issue 12,
1942,
Page 572-594
Lewis E. Wehmeyer,
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摘要:
The 170 species and two varieties of fungi listed from the province are distributed in 70 genera as follows: Perisporiales—seven species and one variety in five genera; Hypocreales—29 species in 12 genera; Sphaeriales—129 species and one variety in 49 genera; Dothideales—five species in four genera. The following species are described as new:Leptosphaeria anisomeres,Physalospora Laricis,Chaetosphaeria multiseptata,Massaria salilliformis,Cryptospora aurantiaca,Diaporthe quadruplex,Xylaria coprophila. The following new combinations are made:Bombardia(Sordaria)lutea(E. & E.),Pseudotrichia(Sphaeria)viridicoma(Cke. and Pk.),Pleospora(Teichospora)nitida(E. & E.),Apiognomonia(Gnomoniella)guttulata(Starb.),Gibberidea(Cucurbitaria)alnea(Pk.).
ISSN:1923-4287
DOI:10.1139/cjr42c-046
出版商:NRC Research Press
年代:1942
数据来源: NRC
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3. |
PROTOPLASMIC CONTINUITY IN THE POWDERY MILDEWERYSIPHE GRAMINISDC. |
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Canadian Journal of Research,
Volume 20c,
Issue 12,
1942,
Page 595-601
Harold J. Brodie,
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摘要:
The protoplasm in the mycelium and conidiophores of the barley mildew (Erysiphe graminisDC.) is continuous from cell to cell. Each transverse septum is provided with a minute central pore through which passes a delicate strand of cytoplasm 1–1.5 μ in width. The cytoplasmic strands and the septal pores have been readily demonstrated by means of a slight modification of Wahrlich's technique, and their presence recorded by means of photomicrographs and drawings. The cytoplasmic connections have also been seen in living unstained mycelium.Streaming of cytoplasm from cell to cell was not observed in the present study, possibly because of the slow rate of flow or because of the difficulty of examining the mycelium without disturbing it.
ISSN:1923-4287
DOI:10.1139/cjr42c-047
出版商:NRC Research Press
年代:1942
数据来源: NRC
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4. |
A STAINING TECHNIQUE FOR EVALUATING THE TOXICITY OF AN ANTIBIOTIC SUBSTANCE OF MICROBIOLOGICAL ORIGIN |
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Canadian Journal of Research,
Volume 20c,
Issue 12,
1942,
Page 602-608
H. Katznelson,
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摘要:
A method is described in which the absorption of neutral red by dead cells ofSchizosaccharomyces pombeis used as an index of the toxicity of an antibiotic agent produced by a bacillus.
ISSN:1923-4287
DOI:10.1139/cjr42c-048
出版商:NRC Research Press
年代:1942
数据来源: NRC
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