PW07 Effects of Multiple Stressors on Marine Resources
Exhibit Hall
8:00 AM - Wednesday
(PW099) Potential use of duckweed for toxicity testing of contaminated aquatic environments.
Hamissou, Mijitaba1, 1 Jacksonville State University, Jacksonville, Alabama, USA
ABSTRACT- Environmental contamination is a frequent phenomenon of industrialized world. A lot of the pollutants released by industrial activities find their way into aquatic and terrestrial ecosystems. The phenomenon is almost always accompanied by a reduction in diversity index and community richness. In plants, environmental contaminants can hinder growth, development, and yield or can be metabolized and be incorporated into the food chain. Some plant species have evolved to sustain high level of contaminants by exuding them though glands or by altering their gene expression to tolerate the toxic effects. Continuous environmental monitoring is necessary to ensure the containment of pollutants. Duckweed, Lemna minor, is an aquatic free floating flowering plant that can be used for toxicity bioassay of contaminated aquatic environments. The objective this study is to investigate some selected physiological and metabolic activities of duckweed grown in liquid media supplemented with various potential environmental contaminants. All plants were screened in Petri dishes containing liquid media containing 50, 100, 150, and 200 micro molar AlCl3.6H2O, CdF2, and NaCLO4.H2O; and 50, 100, 150, 200 mM commercial anti-freeze, ethylene glycol. Three test endpoints, EC50, survivalship, and the activities of antioxidative enzymes were investigated. Preliminary data indicated that duckweed growth is inhibited by elevated concentrations of aluminum, cadmium, and ethylene glycol. Data also indicated a reduction in chloroplast activities followed by an increase in antioxidative enzymes.
Key words: Physiology, Lemna minor, Molecular, Toxicity