Heterobasidion annosum (Fr.) Bref., is a pathogenic hymenomycete which causes white-rot of coniferous trees throughout temperate regions of the Northern Hemisphere. The fungus can be divided into three intersterility groups (IS-groups) in Europe and two IS-groups in North America based on in vitro sexual compatibility and, loosely, on host tree preference. European P, S and F IS-groups prefer pine, spruce and fir respectively, and North American P and S groups prefer pine and fir respectively. This work describes the identification of discriminating characters which reflect underlying genetic differences accumulated between the IS-groups. Two genetic loci in the ribosomal DNA repeat and RFLPs in total genomic DNA were examined. Intraspecific divergence was found in the DNA sequence of PCR amplified internal transcribed spacer region (ITS) in ribosomal RNA repeat unit. It was found that various mutation detection techniques such as RFLP, single strand DNA conformation polymorphism (SSCP), heteroduplex DNA polymorphism and amplification refractory mutation system (ARMS) were applicable for the detection of base variations in the ITS region and therefore for the identification of IS-groups. However, since European S and F strains are genetically closely related to each other, these two were not unequivocally distinguishable. Intergenic spacer region (IGS) in the rRNA repeat unit in H. annosum was also amplified by PCR. The five IS-groups were distinguished by RFLP analysis of the IGS region, though there remained some European S and F group isolates which were also identical at this locus. RFLP in total genomic DNA was seen on ethidium bromide stained agarose gel after electrophoresis and found to be able to differentiate the European IS-groups unambiguously. RFLPs in total genomic DNA revealed with minisatellite probes were also found to be useful for IS-group identification.

Thesis (Ph. D.) in Biological Sciences--University of Maine, 2001. / Includes vita. Includes bibliographical references (leaves 148-166).

No description available.

Thesis (Ph. D. in Plant Pathology)--University of California, Davis, Jan. 1953. / Includes bibliographical references (leaves 65-69). Also available via the World Wide Web. (Restricted to UC campuses).

Thesis (M.S.)--Oregon State University, 1995. / Typescript (photocopy). Includes bibliographical references (leaves 66-74). Also available online.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1925. / Typescript. With this is bound: The influence of plant injury and the root rot diseases upon the physical and chemical composition of corn grain / By George H. Dungan. University of Illinois. Agricultural Experiment Station. Bulletin no. 284. Urbana, Ill., Dec. 1926. p. [253]-281. Bibliography: leaves 75-84.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. Description based on print version record. Includes bibliographical references.

Techn. Universiẗat, Diss., 2002--Braunschweig.

Syftet med denna undersökning är att analysera eventuella löne- och sysselsättningseffekter generade av återinförandet av ROT-avdraget 2008. Återinförandet sågs som en permanent åtgärd med målet att motverka så kallade svartarbeten och öka byggandet i Sverige. Vi vill med denna undersökning utvärdera vilka löne- och sysselsättningseffekter som ROT-avdraget bidragit till. En difference-in-difference metod kommer att användas för att analysera data insamlade från aktiebolag i Sverige, aggregerat till branschnivå. Aggregeringen görs för att våra resultat skall vara direkt jämförbara med tidigare studier, samt för att inte exkludera den effekt som orsakas av att nya företag i dessa branscher kan ha startats på grund av reformen. Difference-in-difference metoden går ut på att en behandlad grupp bestående av de byggbranscher som påverkats av ROT-avdragets införande jämförs med en kontrollgrupp bestående av övriga branscher före och efter reformen. Våra resultat visar att den genomsnittliga lönesumman per anställd inte påverkats av reformen, medan reformen givit en ökning i det genomsnittliga antalet anställda i ROT-branscherna. / The purpose of this paper is to analyze the possible wage and employment effects generated by the reintroduction of the ROT-deduction in 2008. The reintroduction was seen as a permanent measure, and the aim was to counteract undeclared work and to stimulate and increase the building in Sweden. With this paper, we want to evaluate the wage and employment effects that the ROT-deduction contributed to in Swedish construction companies, more specifically limited companies in the ROT industry. A difference-in-difference method will be used to analyze data collected from limited companies in Sweden, aggregated to industry level. Aggregation is made for our results to be directly comparable to previous studies, and to not exclude the effect caused by new companies in the ROT-industry that may have started due to the reform. The difference-in-difference method involves that a treated group consisting of the construction industries affected by the introduction of the ROT-deduction is compared to a control group consisting of other industries before and after the reform. Our results show that the average wage per employee is not affected by the reform, while the reform has increased the average number of employees in the ROT-industry.

No description available.