Comparison of two reference toxicants and their effect upon the growth and development of myriophyllum sibiricum in axenic culture

摘要

A static, 14 day laboratory bioassay using axenic Myriophyllum shibiricum Komarov was develoepd and utilized to determine the effect sof two reference toxicants (zinc chloride (ZnCl_2) and phenol) upon the morphological and physiological development of this species. For ZnCl_2, the highest "no observable effect concentration" (NOEC) was 4.26 mg/L for root length. Based upon IC_(50) values, the most sensitive endpoint parameter for ZnCl_2 was root length (range = 8.2 - 17.8 mg/L), followed by fresh weight (range = 13.2 - 32.4 mg/L) and root number (range = 13.3 - 38.6 mg/L). For phenol, the NOEC was 11.76 mg/L for three endpoint parameters (root number, total root length and fresh weight). Based upon IC_(50) values for phenol, the most sensitive endpoint parameter was root length (32.6 - 40.0 mg/L0, followed by root number (45.8 - 57.0 mg/L) and fresh weight (48.2 - 75.9 mg/L). For both reference toxicants, the results were repeatable over time. As tested in this axenic culturing system, the ZnCl_2 was slightly more toxic to the M. Sibiricum than the phenol.