摘要:

An analysis of the monthly sequence of rainfall during the summer period April-September of the years 1890–1937, made by expressing each annual sequence as a fifth-degree polynomial function of time, indicates that despite marked annual variability the average monthly precipitation at all three stations exhibits a definite seasonal trend, with the maximum incidence of rain in June or July. At Winnipeg, the relative monthly distribution remains, on the average, essentially the same in both wet and dry years, but at Swift Current and Edmonton it is modified to some extent, the midseason maximum being relatively more pronounced in seasons of above-average total precipitation. At Swift Current, both the total amount and one of the coefficients specifying the monthly distribution of precipitation show some oscillatory variation with time; and at Edmonton, there has been a slight progressive change such that a smaller proportion than formerly of the total precipitation now falls in the second half of the season (July-September). No consistent increase or decrease in rainfall over the 48-year period has been recorded at any of the three stations.

ISSN:1923-4287    

DOI:10.1139/cjr41c-012

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

A solution for staining differentially the spores and vegetative cytoplasm of bacteria, yeasts, and certain fungi has been developed. The solution is a mixture of two phenyl methane dyes, malachite green and basic fuchsin; it can be used as a concentrated aqueous solution or as a dilute saline solution. It is not necessary to use heat, though heating is recommended for staining "ripe" spores of bacteria. Decolorization and counterstaining are not required. Bacterial and yeast spores are stained blue or greenish-blue, vegetative cytoplasm light violet or pink. Young bacterial cells stain a deep violet, older cells light violet; the solution can thus be used as a general stain. The acid-fast organismMycobacterium berolinensiswas stained greenish-blue with the granules violet. The saline solution is recommended as a differential stain with young colonies ofAspergillusandPenicillium; the terminal growing tips and young branches of hyphae are stained blue, older hyphae light violet, spores and conidiophores blue.

ISSN:1923-4287    

DOI:10.1139/cjr41c-013

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

Greenwood cuttings ofDeutzia Lemoinei,Symphoricarpus albus, andWeigela roseaand dormant cuttings ofLonicera tataricawere treated with a series of 32 talc dusts containing potassium acid phosphate at concentrations of 0, 0.1, 1.0, and 10%, in combination with 0 and 10% cane sugar, 0 and 50 p.p.m. ethyl mercuric bromide, and 0 and 1000 p.p.m. indolylacetic acid. The lower concentrations of phosphate tended to increase rooting and reduce mortality of two of the species of greenwood cuttings whereas the 10% concentration was ineffective or injurious. However, this concentration was favourable to the rooting of dormant cuttings. Indolylacetic acid treatment increased the number of rooted cuttings and the number and length of roots. Beneficial effects were indicated for organic mercury and cane sugar treatments. However, these were attributed largely to the combinations with phosphate and indolylacetic acid. The results indicate that the effectiveness of dusts containing indolylacetic acid in the treatment of plant stem cuttings may be increased by the addition of nutrient and disinfectant chemicals.

ISSN:1923-4287    

DOI:10.1139/cjr41c-014

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

The hydrolytic activity of 40 pure cultures of bacteria on triolein, as indicated by increased titratable acidity, has been recorded. Schiff and Kreis tests have been made on similar samples of triolein acted upon by pure cultures of bacteria, and the results of these tests are compared with the "oxidase reaction" of the individual cultures.The results indicate that most of the Gram-negative lipolytic organisms also oxidize the fat, and that there appears to be a definite relation between the "oxidase reaction" of a bacterial colony and the ability of the organisms to produce oxidative rancidity.

ISSN:1923-4287    

DOI:10.1139/cjr41c-015

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

A series of observations have been made on the action of 60 cultures of bacteria on globules of triolein in oil emulsion agar media. Lipolytic activity as indicated by the colour reactions of Nile blue sulphate and methylene blue and the blue soap formation with copper sulphate has been shown to coincide with that of the same organisms as measured by the titratable acidity they produced in larger samples of the oil. Other Eh indicators have been shown to colour the globules around lipolytic colonies.Other changes in the colour and texture of the globules have been shown to coincide with the oxidative activity of the bacteria as measured by Kreis and Schiff tests on larger samples as well as by the oxidase reaction of the bacterial colony. Preliminary hydrolysis appears to hasten and intensify the oxidative reactions as indicated by the globules.Other colour reactions in the globules and the formation of various types of crystals have been observed and their significance discussed.

ISSN:1923-4287    

DOI:10.1139/cjr41c-016

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

Studies were made of the effect of temperature and light on the reactions to leaf rust (Puccinia triticinaErikss.) of the differential varieties of wheat used for the identification of physiologic races of this rust. With a large number of races both temperature and light were found to exercise a marked influence. The reactions of all varieties were not, however, influenced in the same direction. With lower temperature, Malakof and Democrat became increasingly susceptible, while Carina, Brevit, and Hussar became increasingly resistant. Webster and Mediterranean did not react consistently in either direction, and Loros was but little influenced by temperature. All of the differential varieties showed a more or less marked tendency to become increasingly resistant under conditions of short day length and weak light. In general, more pronounced changes in reaction were produced by variation of temperature than of light.Surveys for the distribution of physiologic races of leaf rust in Canada were conducted annually since 1931 with the exception of the years 1932 and 1935. Forty-nine races were identified. Most of the prevailing physiologic races were found to be widely distributed throughout the country. Evidence was, however, secured that certain races were largely confined to certain areas. Races 1, 58, 76, and 81 were common for several years in Eastern Canada but were not encountered in the Prairie Provinces until 1940 when one collection of each of the three first-mentioned was made in that area. Races 11 and 53 were largely limited to British Columbia and the adjacent province of Alberta. Races of wheat leaf rust have undergone no marked change in respect to identity or relative prevalence in the last few years in Canada.

ISSN:1923-4287    

DOI:10.1139/cjr41c-017

出版商:NRC Research Press    

年代:1941

数据来源: NRC