Piscicidal plants of Nepal: preliminary toxicity screening using grass carp (Ctenopharyngodon idella) fingerlings.

A survey of traditional fishermen in Chitwan District of Nepal identified the native names of 97 species of plants believed to possess piscicidal properties. Ninety-two were collected and identified. Eighty-two of these were tested for toxicity using grass carp (Ctenopharyngodon idella) fingerlings (2-3 cm total length) as test organisms. Thirty-six species that killed the fingerlings within 2 h at 1% (w/v) extract concentration or less were categorized as poisonous. Forty-six species did not kill fingerling even at 1% extract concentration within 2 h.