摘要:

Mitochondria within leaf cells of healthy broad bean had the normal appearance of plant mitochondria, while within cells infected with bean yellow mosaic virus they had matrices that were electron-opaque and cristae that were swollen and angular. However, upon isolation, mitochondria from healthy broad bean cells became indistinguishable from either mitochondriain situin virus-infected cells, or from mitochondria in vitro isolated from virus-infected cells. Cristae of the isolated mitochondria were greatly inflated, while the matrices were reduced to a thin network in which spherical substructural components, 130–140 A in diameter, were visible. These changes in isolated healthy mitochondria could not be prevented by the use of tannin inhibitors. No significant differences were found in the succinoxidase activities of the isolated healthy and infected mitochondria.

ISSN:0008-4026    

DOI:10.1139/b66-109

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Apices of etiolated decapitated Alaska pea seedlings were painted with aqueous lanolin + IAA ± various inhibitors of RNA or protein synthesis. A subapical segment from the epicotyl was removed for measurements of growth and the soluble protein content and cellulase activity of enzyme extracts.During the first 18 hours, the main growth response to IAA was an increase in segment diameter; elongation was inhibited. The amount of extractable cellulase activity per segment and the diameter increased at exactly the same rates relative to controls. In the next 2 days IAA induced rapid cell division and the formation of root primordia. Cellulase activity per segment, per unit fresh weight, and per unit soluble protein all increased markedly to levels many times higher than in controls. Chloramphenicol, azaguanine, puromycin, and actinomycin D all interfered with protein synthesis, the growth responses, and the development of cellulase activity. In the absence of IAA, cellulase activity decreased.It is concluded that cellulase is subject to turnover in this tissue and that the rate of its synthesis is controlled by auxin concentration. It is proposed that cellulase action on microfibrils in vivo plays an essential role in a variety of growth processes, particularly lateral cell expansion.

ISSN:0008-4026    

DOI:10.1139/b66-110

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

From December 1964 to April 1965 a survey of the marine algae of the Atlantic coast of Halifax County, Nova Scotia was carried out. Within this region 11 collecting stations were established, including sites from the exposed outer coast to the protected area of Halifax Harbour. One hundred and one species were identified: 24 from the Chlorophyceae, 36 from the Phaeophyceae, and 41 from the Rhodophyceae. Seventeen species are new records for Nova Scotia. During the winter months active vegetative and reproductive development was observed. These results have been compared with those obtained previously from this area as well as with results of similar studies made in Massachusetts and Newfoundland–Labrador.

ISSN:0008-4026    

DOI:10.1139/b66-111

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

A new species ofArachniotusis figured and described. This species,A.striatosporus, is characterized by having fusiform ascospores which appear striate in surface view because of the presence of five to nine more or less longitudinal ridges. The ascospores appear stellate in cross section. The species has a conidial state belonging to the form genusOidiodendron.

ISSN:0008-4026    

DOI:10.1139/b66-112

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Supplementation of compost at casing with various ground seeds caused greater increases in mushroom yield than their respective seed oil meals when supplemented and compared at equivalent rates of nitrogen addition.Supplementation with various refined and crude seed oils increased mushroom yield, particularly in the first break or flush of mushrooms. This constitutes evidence for a relationship between lipid metabolism and the initiation of fruiting in the cultivated mushroom,Agaricus bisporus(Lange) Sing.

ISSN:0008-4026    

DOI:10.1139/b66-113

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

A careful study of the floral development ofEragrostis tefindicates that the flowers do not open and that self-pollination is the rule. Observations of the development of the female gametophyte show that it is of the normal monosporic type common to most angiosperms. The three antipodals divide several times as is common in grasses. Study of many ovules before and after fertilization showed absence of any apomictic type of embryo formation. Fertilization was found to occur in the basal floret of a spikelet when that floret was at the base of the flag leaf blade.

ISSN:0008-4026    

DOI:10.1139/b66-114

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Conventional manometric procedures were used to measure oxygen uptake and carbon dioxide evolution by cells of a low-temperature basidiomycete. Total respiration was lowest and, relatively, endogenous respiration was highest in old cells. During starvation, endogenous respiration decreased but did so most rapidly in young cells. Maximum response to exogenous glucose was obtained from young cells after starvation. The respiratory quotient of endogenous respiration fell from 1.0 to approximately 0.7 during starvation, indicating a change in endogenous substrate. Conversely the respiratory quotient for exogenous respiration of added glucose increased with the starvation period. The level of oxidative assimilation of glucose was shown to be high (80-90%) and evidence was obtained that exogenous glucose did not suppress endogenous respiration.The optimum temperature for oxygen uptake was 25 °C, below which theQ10was approximately 2. At 30 °C the rate, while initially highest, decreased during the 6-hour incubation period.The fungus utilized various compounds as carbon sources, but not sucrose in short-term experiments. Glucose, but not xylose was fermented, although the ratio of carbon dioxide to ethanol was not 1:1. Inhibition by fluoride, arsenite, iodoacetate, fluoroacetate, and malonate suggested that both glucose and xylose are respired at least in part by the Embden-Meyerof pathway and the tricarboxylic acid cycle. Endogenous respiration was only slightly affected by these inhibitors.

ISSN:0008-4026    

DOI:10.1139/b66-115

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

A method of growing excised root cultures of leguminous plants was modified for the culture of excised roots ofPinus sylvestrisL. The inclusion of a portion of hypocotyl on the expiants from the seedlings was found essential to obtain sustained growth of the root. With such explants, typical ectotrophic mycor-rhizae were obtained upon inoculation withAmanita rubescens(Pers. ex Fr.) Quel.

ISSN:0008-4026    

DOI:10.1139/b66-116

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Chromosome numbers are presented for 97 taxa of western Canada. A total of 33 are reported for the first time, and of these, the chromosome numbers given forXerophyllum(Liliaceae),n =15,Menziesia(Ericaceae),n= 13, andPhysostegia(Labiatae),n= 19, are the first for these genera. A brief discussion is given for a few of the taxa.

ISSN:0008-4026    

DOI:10.1139/b66-117

出版商:NRC Research Press    

年代:1966

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b66-118

出版商:NRC Research Press    

年代:1966

数据来源: NRC