Marburg, Universiẗat, Diss., 2000.

Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Thesis (Ph.D.)--Murdoch University, 2006. / Thesis submitted to the Division of Science and Engineering. Bibliography: leaves 183-201.

Halle, Universiẗat, Diss., 2001.

No description available.

Thesis (PhD)--Stellenbosch University, 1983. / ENGLISH ABSTRACT: No abstract available / AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar

No description available.

Microorganisms that cause plant disease have been isolated in recirculated irrigation water and increase the risks of disease incidence in horticultural operations. Ozone is an effective oxidizer used to disinfect drinking water supplies and treat industrial wastewater. The objective of this research was to investigate using ozone gas as part of a strategy to reduce the incidence of Phytophthora deBary in recirculated irrigation water. An isolate of Phytophthora capsici Leonian was cultured to induce sporulation. Spore dilutions were placed in aliquots of reverse osmosis water and bubbled with ozone gas (O3) to concentrations of 0 to 1.5 mg·L-1. Ozonated samples were plated and observed for colony forming units. Increasing ozone concentrations reduced the number of colony forming units to 0 at 1.5 mg· L-1 03. Turbidity effects on efficacy on Phytophthora capsici were tested using bentonite clay at 0 to 2.0 nephelometric turbidity units and ozone concentrations of 0 to 1.5 mg· L-1. Increasing bentonite did not affect the efficacy of increasing ozone concentrations on reducing colony formation to 0 at 1.5 mg·L-1 O3. Bioassays using Phytophthora capsici on Capsicum annuum L. seedlings confirmed apparent pathogenicity. Reverse osmosis water, containing a soluble fertilizer at 0 to 300 mg· L-1 N, was ozonated to concentrations of 0 to 1.5 mg·L-1 O3 and used to irrigate Chrysanthemum x morifolium T. de Romatuelle. Increasing ozone concentrations did not interact with increasing fertilizer levels to affect the final growth parameters. Chrysanthemum exposed to ozone gas concentrations of 0.5 to 1.5 mg·L-1 showed symptomatic ozone damage. Complete soluble fertilizer solutions with micronutrients were ozonated from 0 to 1.5 mg·L-1 O3 and analysed for nutrient content. Increasing ozone levels did not interact with fertilizers to affect macronutrients. Increasing ozone interacted with iron at a high fertilizer level. Ozone did not affect the efficacy of paclobutralzol in controlling growth in Viola x wittrockiana. Ozone was effective in controlling Phytophthora capsici in recirculated irrigation water with minimum impact on plant growth. Adjustments in fertility regiemes may be needed to counteract the oxidizing affect of ozone on micronutrients.

Thesis (M.S.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains viii, 56 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 52-56).

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.