Record Details
Field | Value |
---|---|
Title | Requirement for the growth and maintenance of Alphanizomenon flos-aquae in culture |
Names |
O'Flaherty, Larrance Michael
(creator) Phinney, Harry K. (advisor) |
Date Issued | 1966-04-08 (iso8601) |
Note | Graduation date: 1966 |
Abstract | Aphanizomenon flos-aquae from Upper Klamath Lake, Oregon was introduced into culture in a precipitate -free medium developed by modification of McLachlan's ASM medium. This medium ASMT No. 8 contained no organic substances other than ethylendiaminetetraacetate (EDTA) and Trishydroxymethylamino methane (Tris), and was developed by modifying the concentrations of certain elements, by adding sodium bicarbonate and a 1/25 dilution of Arnon's trace element solutions B and C. Cultures of Aphanizomenon in this medium have been maintained in combined daylight and supplemental fluorescent illumination at 15° C. The alga has shown good growth, and has retained the morphological integrity of the colonial flake for more than 14 months. The results of experiments to obtain a medium further improved for the culture of Aphanizomenon, by additional variation of the concentration of elements in ASMT No. 8 are also reported. Preliminary experiments utilizing ultra-violet irradiation and chlorine treatment for elimination of bacteria indicate that bacteria possibly may be removed from cultures of Aphanizomenon. These experiments have determined that exposures can be used that materially reduce bacterial numbers without apparent change in the morphology of the alga. Earlier experiments were made with the alga assumed to be in a unialgal condition as no other alga was demonstrated to be present in the stock cultures. Problems with a contaminating alga, Oscillatoria sp., have since appeared and have not been entirely solved. The complete elimination of Oscillatoria has not been achieved as filaments of this alga were found to grow between filaments of Aphanizomenon, both in the lake and in cultures. Attempts at removal by repeated washing were found to be ineffective. The suggested solution by re-isolation from stock cultures exhibiting, both microscopically and macroscopically, no contamination, has not yet been employed. |
Genre | Thesis/Dissertation |
Topic | Algae -- Cultures and culture media |
Identifier | http://hdl.handle.net/1957/47952 |