39 resultados para Fire extension.
em Brock University, Canada
Resumo:
Fire blight is an economically important disease of apples and pears that is caused by the
bacterium Erwinia amylovora. Control of the disease depends on limiting primaly blosson1
infection in the spring, and rapidly removing infected tissue. The possibility of using phages to
control E.amylovora populations has been suggested, but previous studies have. failed to show
high treatment efficacies. This work describes the development of a phage-based biopesticide
that controls E. amylovora populations under field conditions, and significantly reduces the
incidence of fire blight.
This work reports the first use ofPantoea agglomerans, a non-pathogenic relative ofE.
amylovora, as a carrier for E. amylovora.phages. Its role is to support a replicating population of
these phages on blossom surfaces during the period when the flowers are most susceptible to
infection. Seven phages and one carrier isolate were selected for field trials from existing
collections of 56 E. amylovora phages and 249 epiphytic orchard bacteria. Selection of the .
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phages and carrier was based on characteristics relevant to the production and field perfonnance
of a biopesticide: host range, genetic diversity, growth under the conditions of large-scale
production, and the ability to prevent E. amylovora from infecting pear blossoms. In planta
assays showed that both the phages and the carrier make significant contributions to reducirig the
development of fire blight symptoms in pear blossoms.
Field-scale phage production and purification methods were developed based on the
growth characteristics of the phages and bacteria in liquid culture, and on the survival of phages
in various liquid media.
Six of twelve phage-carrier biopesticide treatments caused statistically signiflcant reductions in disease incidence during orchard trials. Multiplex real-time PCR was used to
simultaneously monitor the phage, carrier, and pathogen populations over the course of selected
treatments. In all cases. the observed population dynamics of the biocontrol agents and the
pathogen were consistent with the success or failure of each treatment to control disease
incidence. In treatments exhibiting a significantly reduced incidel1ce of fire blight, the average
blossom population ofE.amylovora had been reduced to pre-experiment epiphytic levels. In
successful treatments the phages grew on the P. agglomerans carrier for 2 to 3 d after treatment
application. The phages then grew preferentially on the pathogen, once it was introduced into this
blossom ecosystem. The efficacy of the successful phage-based treatnlents was statistically
similar to that of streptomycin, which is the most effective bactericide currently available for fire
blight prevention.
The in planta behaviour ofE. amylovora was compared to that ofErwinia pyrifoliae, a
closely related species that causes fire blight-like synlptoms on pears in southeast Asia. Duplex
real-time PCR was used to monitor the population dynamics of both species on single blossonls.
E. amylovora exhibited a greater competitive fitness on Bartlett pear blossoms than E. pyrifoliae.
The genome ofErwinia phage
Resumo:
An advertisement addressed to the "celebration committees" for May 24th and July 1st. William Hand details his services for fireworks and other lighting. Price ranges are included and reviews/comments quoted from several newspapers.
Resumo:
A fire insurance policy in the amount of one thousand dollars through Aetna Insurance Company of Utica, New York. The cost of twenty two dollars and twenty five cents would give them a one year insurance policy from August 1851 through August 1852.
Resumo:
This paper analyzes versions of the salvo model of missile combat where area fire is used by one or both sides in a battle. While these models share some properties with the area fire Lanchester model and the aimed fire salvo model, they also display some interesting differences, especially over the course of several salvos. Whereas the relative size of each force is important with aimed fire, with area fire it is the absolute size that matters. Similarly, while aimed fire exhibits square law behavior, area fire shows approximately linear behavior. When one side uses area and the other uses aimed fire, the model displays a mix of square and linear law behavior.
Resumo:
List of Employees to be involved in the extension of the Port Dalhousie and Thorold Railway (1 page, handwritten). This is signed by S.D. Woodruff, Nov. 25, 1856.
Resumo:
Letter of estimate sent to S.D. Woodruff for the total cost of construction and equipment of the extension of the line to Port Colborne [this is unsigned]. There is an envelope with this letter that suggests that it is from Mr. Shanly, Mar. 12, 1857.
Resumo:
Chart of estimate of cost of Port Dalhousie and Thorold Railway extension Line no. 1 signed by Mr. Shanly, Mar. 12, 1857.
Resumo:
Report sent to the President and Director of the Port Dalhousie and Thorold Railway stating that the location of the line extension of the railway is completed. The distance from Thorold Station to Port Colborne is 20 miles. The estimate provides for construction of a permanent structure across the Chippewa and Welland River. Estimates for building a first class road, culverts and bridges will be of permanent and durable masonry. This includes estimates for various station buildings such as a warehouse in Port Colborne and a warehouse in Port Dalhousie. Surveys and plans are ready and will be registered this week. This is signed by S.D. Woodruff (2 copies) [one appears to be a rough copy] (The rough copy is 5 pages, handwritten and the other copy is 6 pages, handwritten), Apr. 8, 1857.
Resumo:
Voucher #2 from the Engineer Department of Port Dalhousie and Thorold Railway Extension for surveys, paid to Daniel Plumsteel, Dec. 31, 1856.
Resumo:
Voucher #3 from the Engineer Department of Port Dalhousie and Thorold Railway Extension for sinking test pits, paid to Thomas Woods, Dec. 31, 1856.
Resumo:
Voucher #5 from the Engineer Department of Port Dalhousie and Thorold Railway Extension to George Forbes for surveys, Jan. 31, 1857.
Resumo:
Voucher #6 from the Engineer Department of Port Dalhousie and Thorold Railway Extension to Thomas Woods for surveys, Jan. 31, 1857.
Resumo:
Voucher #7 from the Engineer Department of Port Dalhousie and Thorold Railway Extension to W.G. Thompson accompanied by an abstract of vouchers and summaries of account paid by W.G. Thompson for surveys, Jan. 31, 1857.
Resumo:
Pay roll voucher #8 from the Engineer Department of Port Dalhousie and Thorold Railway Extension for surveys in the month of February, Feb. 28, 1857.
Resumo:
Voucher #9 from the Engineer Department of Port Dalhousie and Thorold Railway Extension to W. G. Thompson accompanied by an abstract of vouchers for surveys, Feb. 28, 1857