ABSTRACT
Aquatic plant testing was later added, with an emphasis on eutrophication studies using growth of freshwater phytoplankton. Standardized test procedures using seaweeds, however, have only recently begun to receive attention. Sexual reproduction tests using green seaweeds have not been developed to date, as it is much more difficult to find a definitive reproductive end point with green algae; many gametes play a dual role as zoospores. Although sexual reproduction is the primary end point, notes on any necrotic tissue within any of the replicates can be useful in later interpretation of results. Females are added to the treatment chambers first, followed by the male plants, so that any reproduction must take place in the presence of the toxicant. The toxicity test procedure using C. parvula was originally developed as a 2-wk test to assess chronic effects of pollutants to marine seaweeds and was evaluated with heavy metals and cyanide.
