Submitted to: International Plant Propagators Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 1/15/2002
Publication Date: 9/10/2002
Citation: Copes, W.E., Chastagner, G.A. 2002. Potential Use of Chlorine Dioxide to Control Diseases in Ornamental Plant Production Systems. Combined Proc. Intl. Plant Propagators' Soc. 51:275-279. Interpretive Summary: Research is being done to evaluate uses of chlorine dioxide in ornamental plant production systems. Chlorine dioxide has been shown to control plant pathogens from contaminating daffodil bulbs during hot water treatment, from damaging rose flowers, and reducing spread of pathogens through recycled irrigation water used to water greenhouse and nusery produced plants. Research has shown that is is not likely that chlorine dioxide treated water will damage many plant species at rates required to kill plant pathogenic fungi. The information will help companies in developing disinfestant products, and extension agents and ornamental plant producers in evaluating use of disinfestants.
Technical Abstract: Research is being done to evaluate uses of chlorine dioxide in ornamental plant production systems. Chlorine dioxide has been shown to control spread of Fusarium oxysporum during the hot water treatment of daffodils and should provide replacement of formaldehyde which was used in the past. By dipping flowers of 'Double Delight' roses in chlorine dioxide, Botrytis gray mold was reduced from 32% severity to 1% severity. Chlorine dioxide is also being used to treat large gallons of irrigation water for the purpose of killing plant pathogens thus reducing their spread from water collection ponds. Rates as low as 1 ppm effective killed pathogens such as Fusarium oxysporum, Thielaviopsis basicola, and Botrytis cinerea. Higher rates of 5 ppm were required if water contained Mn and Fe in solution. Research has shown that is is not likely that chlorine dioxide treated water will damage many plant species at rates required to kill plant pathogenic fungi. If proven effective, some of these application technologies could provide the opportunity to use chlorine dioxide to prcontrol production and postharvest diseases of a number of horticultural crops.