摘要:

A new species ofCyathus, C. setosus, of the Nidulariaceae, is described from Jamaica. The large brown-black cups are beset with long, durable setae. The fruit bodies are unusually thin-walled and very broadly conical. The nearest related species appear to be Lloyd'sC. triplesandC. nigro-albus, from each of whichC. setosusis clearly separable.

ISSN:0008-4026    

DOI:10.1139/b67-001

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

The proteins of wheat grains were studied by the technique of acrylamide gel electrophoresis. This study provided the opportunity to show the effects, on the proteins resolved by these methods, of different factors and variables. These include some items of technique, effects due to the variety to which the grains belong and to the condition known as mottling, and some correlations with the morphology of the grain and with changes that accompany germination. Albumins and globulins were extracted from whole ungerminated mottled and unmottled wheat grains (var. Festival), from embryos of mottled and unmottled grain, and from the various parts of grain germinated for 2, 4, and 6 days under defined conditions. The extracted proteins were separated onacrylamide gels at pH 8.3. Glutens were extracted from the same materials and were separated onacrylamide gels at pH 5.0; some were separated at pH 4.5 also. The albumins and globulins and glutens of the whole ungerminated grain of three varieties of mottled and unmottled wheat are described and differences due to variety and mottling are discussed. The protein patterns of whole grain, dominated by endosperm, were remarkably constant though varietal effects were seen. Albumin and globulin and gluten fractions each had characteristic patterns but the observed differences between mottled and unmottled grain were quantitative, not qualitative. Proteins of embryos differed from those of endosperm and upon germination complementary changes in endosperm and embryo (roots and shoots) proteins could be observed.

ISSN:0008-4026    

DOI:10.1139/b67-002

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

The objectives of the study were to determine the general phytosociological structure of the native prairies, meadows, and marshes of Nelson County, North Dakota; to establish relationships between this structure and factors of the physical environment; and to evaluate the relationships between the vegetation of Nelson County and the True and Mixed prairies. Frequency values and environmental measurements on soil texture, salinity, pH, and an estimate of the drainage regime were obtained in 100 stands selected to represent the vegetational diversity within the County. The drainage regime proved to be the most important single environmental factor in determining the vegetation. A phytosociological drainage regime gradient was then established by assigning indicator values to selected species, and the behaviors of all species and environmental factors were displayed along this gradient. The vegetational display was then divided into six units: the uplands into high prairie, mid prairie, and low prairie and the lowlands into meadow, marsh, and cultivated depressions. Each vegetational unit is described. Comparisons are made between each unit and the related vegetation in surrounding areas. It is concluded that Nelson County should be considered to be within the geographical area of the True Prairie, although the frequent occurrence of western grassland types and western species suggests that the County is within the tension zone between the True and Mixed prairies.

ISSN:0008-4026    

DOI:10.1139/b67-003

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Tracer experiments with14C-labeled compounds showed that phenylalanine, phenyllactic acid, and polyporic acid were readily incorporated into both pulvinic dilactone and calycin. Pulse-labeling experiments with phenylalanine and polyporic acid showed pulvinic dilactone was labeled more quickly than calycin, although eventually calycin may become more heavily labeled. These results can be explained by postulating the following sequence of reactions: phenylalanine → phenylpyruvic acid→polyporic acid → pulvinic acid → pulvinic dilactone → calycin.

ISSN:0008-4026    

DOI:10.1139/b67-004

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

The effect of copper, iron, molybdenum, boron, manganese, and zinc on the growth, morphology, and fruiting of five species ofAspergillus nidulansgroup was examined under controlled conditions. The fungi wereA. nidulans(Eidam) Wint.,A. rugulosusThom and Raper,A. violaceusFennell and Raper,A. varie-color(Berk. & Br.) Thom and Raper, andA. quadrilineatusThom and Raper. Significantly less growth was noticed in all the fungi when all six trace elements were omitted from the culture medium. Also, marked morphological changes occurred in the mycelia and conidiophores of these fungi. The essentiality of manganese, iron, and zinc for growth and fruiting was established for all five fungi. In manganese-deficient cultures the mats were heavily wrinkled and several interesting changes and abnormalities were observed in the conidiophores. The reduction in growth in cultures deficient in copper, boron, and molybdenum varied with the species and their deficiency did not seem to reduce sporulation of these molds. Copper deficiency affected the pigmentation of these aspergilli.

ISSN:0008-4026    

DOI:10.1139/b67-005

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

The relationship has been investigated between stelar diameter, complexity, and the presence or absence of secondary growth in roots ofLinaria vulgaris. Diameter and complexity of the primary xylem body were used as parameters. The presence of secondary growth is considered to be a character of roots developing as long roots. The long roots are responsible for the vegetative propagation of the plant. The frequency of occurrence of secondary growth tends to increase both with stelar diameter and complexity, but secondary growth can occur in roots of any size and complexity. Any root appears to be capable of developing as a long root but the larger roots have a greater chance of so doing. It is thought that roots which are developing as long roots inhibit other roots from such development; probably the larger root apices in any given plant are more capable of escaping from or exerting such inhibition.

ISSN:0008-4026    

DOI:10.1139/b67-006

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

The aim of the series of three papers, of which this is the first, is to produce a rigorous quantitative analysis of variation in vegetation and to correlate the results of the analysis with environmental variation. A general account is given of the Steps Bridge area and of the vegetation studied. The collection of samples of contact between species in the saxicolous bryophyte vegetation is described. To compare the effects of different methods of data processing, four matrices were calculated: a correlation and a dispersion matrix based on the joint and total occurrences of pairs of species in the samples, and a correlation and a covariance matrix based on the occurrences of pairs of species with all the other species in the samples. Results of principal components analyses of the four matrices are presented and compared and the appropriate circumstances for the use of each type of matrix are indicated. The components analyses are analyses of the distributional relationships of the species and are based on rigorous statistical treatment throughout.

ISSN:0008-4026    

DOI:10.1139/b67-007

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Leaf area per plant, total number of leaves and tillers, and total plant dry weight increased with increasing daylength over the range 8 to 24 h. The increase in the net assimilation rate and relative growth rate with increasing daily total radiation was similar to that obtained by raising the intensity of light given to plants grown under continuous illumination.During the vegetative phase of growth, the leaf area ratio decreased with increasing daylength, mostly because of an increased leaf thickness, again dependent on the level of total daily radiation. During the later stages of growth, earlier floral initiation at long daylengths caused an early decline in the leaf area ratio because of the rapid growth of the stem associated with inflorescence formation. This was a photoperiodic effect independent of the level of total daily radiation, as shown by supplementing an 8-h daylength with 8 h of low-intensity illumination.

ISSN:0008-4026    

DOI:10.1139/b67-008

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

The incipient symptoms of needle blight of eastern white pine (Pinus strobusL.) appear only in semimature tissues of current year needles, and the orange-red lesions then spread acropetally throughout adjacent, more mature, tissues. Semimature tissue of white pine needles is characterized by the start of the suberization of the radial and transverse walls of the endodermal cells. The first cells to break down in blighted semimature tissue occur in the mesophyll region of one of the ventral faces of the needle. Mesophyll necrosis spreads laterally to the other ventral face and finally to the dorsal face of the needle, before proceeding distally through mature tissue. Anatomical differences exist between needles collected from susceptible and non-susceptible white pines.

ISSN:0008-4026    

DOI:10.1139/b67-009

出版商:NRC Research Press    

年代:1967

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b67-010

出版商:NRC Research Press    

年代:1967

数据来源: NRC