Effects of Six Herbicides on Three Common Fresh Water Algae

Author

• Mridulika Virmani, Utah State University

Date of Award:

5-1972

Document Type:

Dissertation

Degree Name:

Doctor of Philosophy (PhD)

Department:

Plants, Soils, and Climate

Department name when degree awarded

Botany

Committee Chair(s)

Raymond Lynn

Committee

Raymond Lynn

Committee

J. O. Evans

Committee

Donald Porcella

Committee

Robert Gearheart

Abstract

Six herbicides (diuron, karbutilate, propham, chloropropham, atrazine and simazine) were tested for their effects on Chlorocuccum hypnosporum, Chlorella pyrenoidosa and Anabaena sp. Experiments were conducted to determine minimum lethal dosages, algicidal versus algistatic concentrations and the uptake of ¹⁴CO₂ fixation by diuron containing cultures, as well as the uptake of radioactive diuron.

All three investigated species have shown a high degree of sensitivity to diuron at or below 1 ppm. Karbutilate was found to inhibit the growth of Chlorella pyrenoidosa and Anabaena sp. at lower concentrations than were required in the case of Chlorococcum hypnosporum.

Chloropropham was found to be effective at lower concentrations than propham. Exposure to either of these herbicides resulted in cytological abnormalities of treated cells.

Inhibition of all three genera proved to be effected by exposure to atrazine and simazine at low concentrations. Simazine at 4 ppm was algicidal to Chlorella pyrenoidosa and Anabaena but this concentration was only sufficient to reduce growth of Chlorococcum hypnosporum.

Diuron at 0.5 ppm was shown to exhibit inhibitory effects on ¹⁴CO₂ fixation. Chlorococcum hypnosporum was shown to carry out active uptake of radioactive diuron, while uptake by Chlorella pyrenoidosa appeared to be passive.

Recommended Citation

Virmani, Mridulika, "Effects of Six Herbicides on Three Common Fresh Water Algae" (1972). All Graduate Theses and Dissertations, Spring 1920 to Summer 2023. 9104.
https://digitalcommons.usu.edu/etd/9104