Record Details
Fungitoxicity of silver salts
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Fungitoxicity of silver salts |
| Names |
Guilford, Roger Kirby
(creator) Corden, Malcolm E. (advisor) |
| Date Issued | 1963-05-13 (iso8601) |
| Note | Graduation date: 1963 |
| Abstract | The demand for new fungicides to control plant diseases has led to experimentation with both previously used and newly developed fungicides. Silver, an older but little used fungicide, was selected for evaluation because of its high toxicity to microorganisms. Silver nitrate and a silver electrolytic cell were tested as potential sources of silver ions. The cell discharged 0.17 ppm silver ions into 750 ml of distilled water during a ten-minute period. A bioassay was used to detect silver ion concentrations. Approximately 1.5 ppm silver ion per 100 ml of cell effluent was lost from the electrode under constant flow conditions. The cost of producing 1000 gallons containing 1 ppm of silver with the silver electrolytic cell was $1.11 vs. $0.20 for silver nitrate. The effluent from the electrolytic cell remained fungitoxic for at least five days after preparation, after which time toxicity gradually diminished. Ionic silver was not phytotoxic to sword-fern fronds or potato tubers at concentrations much greater than the level required to control dry rots of fern and potato. The concentration of silver nitrate necessary to effectively control the spread of dry rot of fern stored at 34° F was 1.0 ppm. This disease is caused by a complex of a Fusarium sp. and a Pseudomonas sp. and is particularly severe at elevated temperatures. The most effective method of applying silver to fronds was by dip treatment of frond bundles. Undiluted silver effluent (0.17 ppm) effectively controlled dry rot of potatoes caused by the fungus, Fusarium roseum. However, ionic silver discharged from the silver electrolytic cell was not effective as a pre-harvest treatment for the control of apple scab and peach leaf curl diseases. |
| Genre | Thesis/Dissertation |
| Topic | Fungicides |
| Identifier | http://hdl.handle.net/1957/49135 |
