摘要:

A chromatographic method for the qualitative and rough quantitative estimation of sugars and soluble phosphates in plants is described. Using this method, representatives of 27 families of Spermatophyta and 10 representatives of Algae have been examined. In Spermatophyta the total sugar content was found to be fairly high, with sucrose usually the main sugar, and glucose predominating over fructose. In Chlorophyta, the concentration and the nature of the sugars present were fairly similar to those in Spermatophyta. In Phaeo-phyta, Rhodophyta, and a diatom Nitzschia, the soluble sugar content was very low, with glucose usually being the main sugar. The distribution of sugars in aquatic Spermatophyta was similar to that of terrestrial Spermatophyta rather than that of Algae. When wheat leaves were detached and placed on water in darkness, subsequent metabolism of their sugars was found to be markedly affected by the conditions of illumination prior to leaf detachment. On illumination, detached wheat leaves accumulated large amounts of alcohol soluble fructosans, while attached leaves did not. In detached wheat leaves during prolonged starvation, soluble phosphates, both organic and inorganic began to accumulate after two days, indicating breakdown of some insoluble forms of phosphorus. By this time free sugars had completely disappeared, though sucrose reappeared in relatively large amounts on the third day and then declined again.

ISSN:0008-4026    

DOI:10.1139/b52-021

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

Spinach leaf carbonic anhydrase has been used as a tool in the Krebs-Roughton technique to determine whether several plant decarboxylase systems give rise to carbon dioxide or bicarbonate as the primary end product. The results show that in addition to the urease – urea and yeast carboxylase – pyruvic systems, the plant enzyme systems decarboxylating pyruvic, oxalacetic, glutamic, and α-ketoglutaric acids produce carbon dioxide and not bicarbonate as the primary end product.

ISSN:0008-4026    

DOI:10.1139/b52-022

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

Cultures from field collections ofSeptoria avenaeFrank produce "wild type" colonies of rather uniform appearance—a creamy-white mycelium, a brown substrate, and few, if any, pycnidia. Subculturing on potato sucrose agar usually leads to the production of a great variety of variants that fall into two broad classes: mycelial and pycnidial, the latter usually producing scant mycelium, many pycnidia, and a blue-green substrate pigment. In some cultures, staling, i.e., cessation of growth, occurs commonly but is generally followed, after an interval of time, by renewed growth. Cultures of the pycnidia! type show a marked tendency to produce mycelial type variants and, conversely, cultures of the mycelial type will give rise to pycnidial type variants. In certain cultures, strains have arisen that predominantly produce small pycnidia containing spermatium-like microspores, but which are still capable of producing macro-spores. Cultures from microspores show several distinct types including dark-pigmented cultures, albino cultures with dark pycnidia, albino cultures with colorless pycnidia, and cultures of purely mycelial type. Attempts to demonstrate that the microspores perform a function in the production of the perfect stage of the organism were unsuccessful.

ISSN:0008-4026    

DOI:10.1139/b52-023

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

The experimental results obtained in this study indicate that proteins or amino acids are not necessary for the production of high yields of the amylolytic enzymes, alpha-amylase, maltase, and limit dextrinase. However, in cultures which produce appreciable transient acids during the fermentation the use of a nitrogen source which is a potential alkali donor greatly increases the yield of alpha-amylase. Ammonium acetate fulfills this requirement, and under appropriate conditions it gives high yields of alpha-amylase, maltase, and limit dextrinase. The accumulation of maltase and limit dextrinase is inhibited when the pH of the medium rises above eight, whereas an acid pH as low as four is still suitable for their production.

ISSN:0008-4026    

DOI:10.1139/b52-024

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

Some notes are given concerning the structure and occurrence of phialides and phialospores and their relationship with spermatia. The genusPhialophorais not sharply delimited and with many transitional species gradually merges with several genera of the Fungi Imperfecti. A new speciesPhialophora radicicolaCain, is described from the roots of corn in Ontario.

ISSN:0008-4026    

DOI:10.1139/b52-025

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

During the summer of 1950,Phialophora radicicola, was found on corn roots in soil near Chatham, Ridgetown, and Harrow, Ont. Owing to its color and parasite-host relations, it may have been mistaken previously forRhizoctonia solanior aRhizophagusspecies. It can be isolated only when a piece of apparently healthy corn root tissue with the adhering mycelium is removed from an infected root and placed on agar media. After two or three months of culture on nutrient and on potato dextrose agar,P.radicicolalost its ability to sporulate, but this ability was revived when it was cultured on moist corn roots. No sexual stage of the organism has been found. The fungus may attack corn roots at any time throughout the season and its brown runner-hyphae or macrohyphae grow parallel to the roots. The finer infection hyphae or microhyphae penetrate the outer root tissue and their infection threads are surrounded by "wall tubules". The fungus is quite aggressive, but not very pathogenic, and apparently it is followed by numerous secondary organisms. The similarity of this organism toOphiobolus graminisis very noticeable.

ISSN:0008-4026    

DOI:10.1139/b52-026

出版商:NRC Research Press    

年代:1952

数据来源: NRC