Acute toxicity of Amanranthus viridus extract on guppies, Poecilia reticulata.

Many Thai plant species shows the responsible for controlling insects from the host plants. To avoid potential toxic pollutant contaminating aquatic ecosystems, this present study was investigated for acute toxicity from Amaranthus viridis to Guppy fish (Poecilia reticulata) were selected for the bioassay experiments. The experiments were repeated 5 times and the 1-, 3- and 24-h LC50 was determined for the guppies. The acute toxicity experiments were carried out by static method and behavioral changes in guppies were determined for Amaranthus viridis concentration extract which extracted by Soxhlet's extraction method with ethanol as solvent. Water temperature was regulated at 20 +/- 1 degrees C. Data obtained from the acute toxicity tests were evaluated using the Probit analysis statistical method. The 24-h LC50 value for guppy was estimated as ca. 947 mg L(-1) (r2 = 0.95). However, in this concentration, no mortality was observed at higher concentration for 30 second.