摘要:

Perithecia ofVenturia inaequaliswere produced in vitro on apple leaf discs which had been sterilized in propylene oxide and then placed on water agar, potato-dextrose agar, or potato-dextrose agar supplemented with apple leaf decoction. The discs were inoculated with a drop of a conidial suspension of two sexually compatible strains ofV. inaequalis, incubated at room temperature for 2 weeks, and then grown at 8 °C for 4 to 5 months.Perithecia were also produced on sterile leaf discs placed on perlite, vermiculite, sand, filter paper, or glass rings in screw-cap vials with distilled water added to supply moisture. Using perlite, perithecia were developed on discs of green and fallen apple leaves collected from the orchard at intervals during the summer and fall and on leaves at different stages of development from trees growing in the greenhouse. Few perithecia developed on newly unfolded leaves from the latter unless the leaves were leached before inoculation. Perithecia developed on sterile discs from green apple leaves of varieties with varying degrees of susceptibility toV. inaequalisand on green leaf discs of the pear variety Kieffer. Perithecia production was most abundant at 4 °C and no perithecia were produced at or above 15 °C.

ISSN:0008-4026    

DOI:10.1139/b62-059

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

A method for the inoculation of Douglas fir roots withPoria weiriiusing Douglas fir, alder, maple, and oak wood for preparing the inoculum is described. When the deciduous wood was used as the food base on which the fungus was grown, a higher percentage of infection was achieved than when either Douglas fir stem or roots were used. Six months was sufficient time for the fungus to become well established on the bark surface; penetration of healthy bark occurred in 12 months. Spread of the fungus to adjacent roots at points of root contact was noted. Growth of mycelium on the bark surface was usually well in advance of infection in the wood.Poriamycelium continued to grow vigorously during the fall and winter months of the study period.

ISSN:0008-4026    

DOI:10.1139/b62-060

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

Forty-nine cultural types ofMycosphaerella fragariae(Tul.) Lindau are placed in six groups according to their virulence on nine strawberry varieties varying in field resistance. It is suggested that each of the six virulence groups represents a physiologic race. It is also suggested that the variation in leaf spot resistance in different areas is due to the presence of these races, and that they must be considered when breeding for resistance.

ISSN:0008-4026    

DOI:10.1139/b62-061

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

A virus disease that occurs on red raspberry in the Okanagan Valley in British Columbia was identified as raspberry leaf curl. Under experimental conditions the virus was transmitted by the aphidAphis idaciV. d.G. Test plants included red raspberry,Rubus idaeusL.; black raspberry,Rubus occidentalisL.; wineberry,Rubus phoenicolasiusMaxim.;Rubus henryiHemsl. & Kuntse; and the Alpine strawberry,Fragaria vescaL. The virus did not infect black raspberry and caused only transitory symptoms on Alpine strawberry. Root cuttings of red raspberry, leaf-bud cuttings ofR. henryi, and seedlings of wineberry provided satisfactory indicator plants. Wineberry andR. henryiwere more readily inoculated by aphids than red raspberry. Non-viruliferous aphids required a feed of at least 1 day on the virus source to acquire an infective charge. When viruliferous aphids were transferred to a series of healthy indicator plants, some plants became infected after a test access time of 20 minutes, although transmissions were increased if the time was increased to 1 hour. The virus was found to persist in viruliferous aphids for at least 11 days. Leaf curl virus was not eliminated from infected plants held at an air temperature of 37 °C for periods up to 4 weeks.

ISSN:0008-4026    

DOI:10.1139/b62-062

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

Apical and radial growth, and the developmental anatomy of vegetative and reproductive buds ofPicea glauca, were investigated. Apical growth of the leader occurred from mid-May until mid-July, that of the side branches from mid-May until late June or early July. Total apical growth of the side branches, in general, diminished with their distance from the leader. Initiation of radial growth started in the main axis behind the terminal bud and moved basipetally along the trunk. Cessation of radial growth followed the same order.The apex of the vegetative bud developed in late July or early August includes a central zone, a peripheral zone with needle primordia, and a basal zone of thick-walled cells. Reproductive buds could be recognized by early August as oblong structures with globose appendages. By mid-August, these appendages had differentiated into either pollen sacs with pollen mother cells in the male buds, or into bracts and ovuliferous scales in the female ones. The female cone entered winter with little visible internal differentiation. The influence of temperature fluctuations on vegetative and reproductive growth is discussed.

ISSN:0008-4026    

DOI:10.1139/b62-063

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

Representatives of C14-labelled sugars, amino acids, and organic acids were placed on several different kinds of exchange resins and their absorption and elution from such resins was determined. From the data obtained, a combination of IR 120 in the H+form and IRA 400 in the formate form was selected for the initial separation of pine extracts into their sugar, amino acid, and organic acid fractions. These fractions were resolved further by two-dimensional paper chromatography.Two-year-oldPinus strobusseedlings were illuminated in C14O2for 8 hours either at 2500 or 250 ft-c. Then their shoots were extracted with 80% ethanol and the distribution of C14in various components of the photosynthate was determined, as described above.The results obtained were essentially the same for seedlings illuminated either with 2500 or 250 ft-c. Not more than 10% of the absorbed C14were found in the ethanol-insoluble residue. About 98% of the ethanol-soluble C14were found in the sugar fraction, with the remaining 2% being about equally divided between the amino and organic acids. Sucrose formed about 75% of the sugar fraction, with glucose and fructose making up additional 20%. Only small amounts of raffinose were found.

ISSN:0008-4026    

DOI:10.1139/b62-064

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

The phenolic acid pattern of 17 species ofImpatiensis presented. The presence of naphthoquinone derivatives in four new species is reported. A discussion of some prominent unidentified phenolic compounds on two-directional chromatograms is presented which includes discussion of possible forms in which naphthoquinones may exist in the living plant. The identification of scopoletin (6-hydroxy-7-methoxycoumarin) in several species studied marks the first report of this compound in the Balsaminaceae.

ISSN:0008-4026    

DOI:10.1139/b62-065

出版商:NRC Research Press    

年代:1962

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b62-066

出版商:NRC Research Press    

年代:1962

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b62-067

出版商:NRC Research Press    

年代:1962

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b62-068

出版商:NRC Research Press    

年代:1962

数据来源: NRC