Hostname: page-component-89b8bd64d-5bvrz Total loading time: 0 Render date: 2026-05-07T10:58:30.860Z Has data issue: false hasContentIssue false

A Rapid Bioassay for Selective Algicides

Published online by Cambridge University Press:  12 June 2017

Kevin K. Schrader
Affiliation:
Southern Regional Aquaculture Center, Delta Research and Extension Center, Stoneville, MS 38776
Marjan Q. De Regt
Affiliation:
Southern Regional Aquaculture Center, Delta Research and Extension Center, Stoneville, MS 38776
Craig S. Tucker
Affiliation:
Southern Regional Aquaculture Center, Delta Research and Extension Center, Stoneville, MS 38776
Stephen O. Duke
Affiliation:
USDA-ARS, Southern Weed Science Laboratory, P.O. Box 350, Stoneville, MS 38776

Abstract

Cyanobacteria (blue-green algae) are undesirable in ponds used to raise fish for human food. Management of cyanobacterial communities in aquaculture ponds has been hindered by the small number of herbicides approved for use in food-fish ponds and by the lack of selectivity toward cyanobacteria for those herbicides that are approved for that use. To facilitate development of additional management options, a rapid bioassay utilizing 96-well cell culture plates was developed for screening herbicides and other phytotoxins for selective toxicity toward cyanobacteria. Oscillatoria cf. chalybea and Selenastrum capricornutum were chosen as representatives of cyanobacteria (Cyanophyta) and green algae (Chlorophyta), respectively. In the bioassay, wells of the cell culture plates were inoculated with cyanobacterial or unialgal culture. One of five herbicides (atrazine, diuron, endothall, fluridone, or paraquat) was then added to the wells at various concentrations, and absorbance (650 nm) was measured at 24-h intervals. Growth of treated cultures relative to untreated cultures was used to determine relative toxicity of the herbicide to the two organisms. Paraquat was the most selective of the herbicides tested and was over 10-fold more toxic to O. cf. chalybea than to S. capricornutum. This method was demonstrated to be a rapid, effective, and highly reproducible bioassay to identify selective algicides.

Information

Type
Research
Copyright
Copyright © 1997 by the Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable