摘要:

A virus disease of red raspberry that has been known in Oregon and Washington for several years was observed for the first time in British Columbia in 1961. The disease is characterized by chlorotic blotches, ringspot, or oak leaf markings, or a net-like chlorosis along the smaller veins of the leaves on the young canes. The virus nature of the disease was demonstrated by mechanical transmission from raspberry leaves to herbaceous plants. From physical properties and symptoms on a range of herbaceous hosts and peach seedlings, the virus was considered to be related to tomato ringspot virus. This relationship was confirmed by comparative host reactions and cross protection studies with known strains of tomato ringspot virus.

ISSN:0008-4026    

DOI:10.1139/b62-086

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

Some North American aphylloid species ofScirpusare discussed in detail with particular emphasis on Asiatic–American relationships. Beetle, in 1947, recognized 27 species in this group; 15 of his species examined in the present treatment are reduced to 8. The following new combinations are proposed:S. juncoidesvar.Williamsii, S. Smithiivar.leiocarpus, S. supinusvar.saximontanus, S. lacustrisssp.validus, S. lacustrisssp.validusvar.luxurians, S. subterminalisvar.cylindricus, S. subterminalisssp.nipponicus, andS. maritimusf.cymosus.

ISSN:0008-4026    

DOI:10.1139/b62-087

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

Plants were grown to the stage of anthesis at constant temperatures from 10 to 30 °C and under continuous illumination at intensities ranging from 200 to 2500 ft-c. The absolute growth rate was maximal at the time of ear emergence. The relative growth rate declined continuously with time; the rate of decline was greatest at the higher temperatures and light intensities. The optimal temperature for the mean absolute growth rate over the whole growth period was 20–25 °C. The optimum for the mean relative growth rate was 15–20 °C. This difference is attributed to the faster rate of floral development at high temperatures. Both absolute and relative growth rates increased with increasing light intensity up to 2500 ft-c.

ISSN:0008-4026    

DOI:10.1139/b62-088

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

A simple medium was found for the production of antibiotic P-9 used in experiments for the control of stem rust of wheat.A rust-infection bioassay method for the estimation of the potency of different production lots of filtrate was developed; potency was measured as the proportionate inhibition of stem rust (Puccinia graminisPers. f. sp.triticiErikss. & Henn. race 15B) infection on wheat seedlings in relation to log concentration of the material under test. The data from the bioassays took the form of a sigmoid curve when the concentrations were plotted arithmetically and of a straight line when they were plotted logarithmically. The slope of a weighted mean regression line based on 11 assays was regarded tentatively as characterizing pure antibiotic P-9.When the data of the 11 assays were adjusted for differences in potency between assays, the weighted mean regression line was statistically significant at the 1% point of probability. It is hoped that the slope of this line characterizes the pure antibiotic P-9 sufficiently well to be a useful tool in estimations of the relative purity of fractions obtained in the progressive purification of the antibiotic. Regression lines that differ from it substantially in slope may be suspected of influence from some extraneous factor.

ISSN:0008-4026    

DOI:10.1139/b62-089

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

A previously described photoresponse of lettuce seed germination to red and far-red light is shown to be paralleled by a response of phosphate metabolic activity: (1) When seeds were continuously irradiated, red light accelerated and far-red suppressed their phosphate uptake and esterification. (2) The influence of monochromatic light on phosphate metabolism of seeds, determined after 36 and 64 hours of germination, respectively, indicated maximum potentiation between 550 and 650 mμ, maximum suppression beyond 700 mμ, and partial suppression at 475 mμ. Stimulation was encountered at 400 mμ, but with shorter wavelengths of the ultraviolet spectrum, suppression appeared again. (3) Photoactivation of phosphate metabolism in response to each of the three loci (550, 600, and 650 mμ, i.e., green, orange, and red light, respectively) of the potentiating spectral band was reversed by far-red (750 mμ) light. These activations and inhibitions could be reversed several times in an alternating sequence. Complete reversibility depended entirely upon the magnitudes of the radiant flux for the two counteracting wavelengths, and this was characteristic for each pair of antagonistic wavelengths. In view of the association of phytochrome with the isolated mitochondria and of the specific manner in which their phosphorylation activity is influenced by light, it is suggested that a part of the energy flow required for cellular development may be channeled through the mitochondrial–phytochrome system.

ISSN:0008-4026    

DOI:10.1139/b62-090

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

Inorganic, organic, and various organic phosphate fractions were determined in uninfected and infected first seedling leaves of Little Club wheat at various stages between 6 to 18 days after incubation withPuccinia graminis triticiErikss. and Henn. (Race 15B). Inorganic (Pi), organic (Po), and total P per unit fresh weight increased as uninfected leaves aged and the levels of Pi were much more readily altered by changes in nutritional status and environmental conditions than the levels of Po. Infection increased total P and the highest concentrations occurred at the loci of rust pustules. Since the concentration of P was lower in uninfected portions of infected leaves than in comparable parts of uninfected leaves or in rust pustules, it appeared that P was transported into the pustules from uninfected parts of the leaf. Both Pi and Po were increased by infection, but the Pi/Po ratio was lowered. Acid-soluble bound P, easily hydrolyzable P, lipid P, RNA-P, and residual organic P were all increased by infection.When leaf pieces were infiltrated with and then floated on 10−4 M2,4-dinitrophenol for 24 hours, the levels of all organic phosphate fractions were lowered and Pi was increased, both in uninfected and infected leaves. Dinitrophenol raised the Pi/Po ratio about 30% in uninfected and about 100% in infected leaves.The results militate against the view that the increase in respiration rate caused by infection is due to the uncoupling of oxidative phosphorylation.

ISSN:0008-4026    

DOI:10.1139/b62-091

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

Genetical and morphological evidence supports the validity of three species of red polypores:Pycnoporus cinnabarinus(Jacq. ex Fr.) Karst., which occurs in the North Temperate zone;P. coccineus(Fr.) Bond. & Sing., which occurs in the South Temperate zone and in countries bordering on the Indian and Pacific Oceans; andP. sanguineus(L. ex Fr.) Murr. in tropical and subtropical regions of the Northern and Southern Hemispheres. Descriptions of carpophores and cultures are given for each species along with a revised description of the genusPycnoporusKarst.

ISSN:0008-4026    

DOI:10.1139/b62-092

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

The genusEuzoniaKylin is rejected because the species included in it form only part of an evolutionary series of closely related entities hitherto referred to the genusEuzoniellaFalkenberg. Furthermore, because of the additional confusion that has resulted from referring only a part of this series toDasycloniumJ. Ag. (sensu Kylin), and because an earlier proposal to conserveEuzoniellahas been rejected, it would seem best to refer all entities to the one genusDasycloniumJ. Ag. The morphological evidence resulting from a recent study of more extensive material and the types of additional species further supports this conclusion. Also supported is the opinion thatD. ocellatum(Yendo) Scagel andD. flaccidum(Harvey) Kylin are probably conspecific; and, furthermore, that these questionable species might, with justification, be reduced to synonymy withD. incisum(J. Ag.) Kylin; and thatD. adiantiformis(Decaisne) Scagel andD. cuneifolium(Montagne) Scagel may be merely extremes in a series of plants representative of one variable species (D. adiantiformis). These reductions to synonymy, however, should not be made until an ecological study has been undertaken to determine the limits of variability within the complex. A distinctive entity, based upon Laing's No. 40 from the Snares, New Zealand, and referred by him toEuzoniella flabellifera(J. Agardh) Laing, is described asDasyclonium bifurcatumsp. nov.

ISSN:0008-4026    

DOI:10.1139/b62-093

出版商:NRC Research Press    

年代:1962

数据来源: NRC