Record Details
Field | Value |
---|---|
Title | The effects of CIPC vapors on dodder (Cuscuta spp.) seedlings |
Names |
Slater, Clarence Harold
(creator) Furtick, William R. (advisor) |
Date Issued | 1967-02-06 (iso8601) |
Note | Graduation date: 1967 |
Abstract | The use of CIPC (isopropyl N-(3-chlorophenyl) carbamate) to control dodder (Cuscuta spp.) in alfalfa is an established practice. A rate of six pounds per acre applied to moist soil has given good dodder control lasting from four to six weeks. The purpose of this study was to determine the effect of CIPC vapors on dodder seedlings. In order to obtain a relatively high percent germination of dodder seeds, the seeds were scarified with concentrated sulfuric acid and planted in sterile soil. Since dodder is a parasitic plant it was necessary to find a suitable host plant. Alfalfa and carrots were used in initial experiments and toothpicks were substituted for the host plants in later experiments. It was found that dodder seedlings would wrap around toothpicks and haustoria would develop. Control of dodder seedlings was measured by counting the number of wrapped or attached dodder seedlings on a suitable host. Dodder seedlings were exposed to CIPC vapors in a closed plastic vapor trap system. Twenty percent granular CIPC at six pounds per acre was applied to moist soil within the vapor trap. Exposure of dodder seedlings to CIPC vapors for 2, 4, 8, 16, 32, and 64 hours indicated that at least 16 hours exposure was necessary to prevent seedlings from wrapping. A similar experiment was carried out using CIPC at six pounds per acre on dry soil. Complete control of dodder seedlings was obtained in each experiment. Dodder seedlings were grown in 12 x 75 mm test tubes. They were then exposed to CIPC vapors released from CIPC granules in the open greenhouse. The test tubes provided assurance that all contact between CIPC and the dodder must have been as a vapor. In all cases the seedlings failed to wrap around the toothpicks. Data from a field experiment using the test tube method and alfalfa as a host showed positive dodder control as a result of CIPC vapor toxicity. An attempt was made to determine whether CIPC in the soil solution or CIPC vapors were most active in controlling dodder seedlings. In all cases seedlings were isolated from CIPC in soil solution. The vapors released did prevent wrapping of dodder seedlings on the toothpicks. A suitable method was not found which would assure only exposure of dodder seedlings to CIPC in the aqueous form. The evidence collected shows that CIPC vapors are important in the control of dodder seedlings. |
Genre | Thesis/Dissertation |
Topic | Herbicides |
Identifier | http://hdl.handle.net/1957/47208 |