Record Details
Field | Value |
---|---|
Title | The reproduction and mode of spread of sago pondweed (Potamogeton pectinatus L.) in irrigation system |
Names |
Ogg, Alex G.
(creator) Appleby, Arnold P. (advisor) |
Date Issued | 1966-05-13 (iso8601) |
Note | Graduation date: 1966 |
Abstract | Nine experiments were conducted during 1964 and 1965 to study the methods of reproduction and mode of spread of sago pondweed (Potamogeton pectinatus) in irrigation systems. Frequent treatments of sago pondweed foliage with aromatic solvent greatly reduced the number of tubers in the substratum of an irrigation canal. However, complete eradication of all tubers in one irrigation season was not obtained. Ecological investigations revealed that sago pondweed was capable of invading and becoming established in new irrigation channels in one season. The propagules responsible for the establishment of new infestations were tubers and plant fragments. Considerable numbers of sago pondweed seed were transported into the new channels by the water, but no seedlings were found. Sago pond-weed tubers survived freezing temperatures under field conditions. Subsequent studies in the laboratory showed that sago pondweed tubers could become somewhat hardened or conditioned to withstand freezing temperatures. Removal of the parent tuber did not affect the survival of emerged shoots nor did it prevent the growth of excised sprout tips. The main portion of the tuber appeared to have a function other than initiating growth. The study of shoot emergence from tubers indicated a relationship between the weight of the tuber and the depth from which the shoot would emerge. The main portion of the tuber, whose dry weight consists primarily of carbohydrates, may function as a food reserve enabling the shoot to emerge from a considerable depth in the soil. Sago pondweed seeds that had overwintered in a canal bottom gave 15 percent germination in a greenhouse aquarium after a 50-day period. Seeds that had passed through the digestive tracts of wild-ducks germinated abundantly. However, if the seeds were held in the digestive tract for more than three days, no germination occurred. The storage of sago pondweed seeds at different conditions of temperature and moisture for different periods of time resulted in significant differences in the percentages of germination. Storage of seed in water at 0.0 degrees C. for 12 days resulted in the highest percentage of germination. The seed germination studies indicated that the importance of seed in the spread of sago pondweed in irrigation systems may be underestimated. |
Genre | Thesis/Dissertation |
Topic | Helobiae |
Identifier | http://hdl.handle.net/1957/47933 |