Molluscicidal and Piscicidal Activities of Extracts of Castor (Ricinus communis) Bean for Aquaculture Management

Abstract

The study assessed the molluscicidal and piscicidal activities of castor plant Ricinus communis using its fruit (dried and fresh) against large and small golden apple Snails (GAS) and mosquito fish. We focused on the laboratory determination of lethal concentrations LC50 and LC100 through a static bioassay test. Separate experiments were performed for GAS and mosquito fish and ten experimental animals where stocked in each experimental unit. Based on a 24-hour lethal concentration (LC100), the toxicity for large GAS was 96.21 ml/L for fresh fruits, 124.02 ml/L for dried beans. For small GAS, the toxic concentrations were 91.75 ml/L for dried beans, and 105.89 ml/L for fresh fruits. For the 24-h LC50, the toxicity to large GAS of the two extracts were 47.05 ml/L for dried beans, and 39.28 ml/L for fresh fruits, and for small GAS they were 44.87 ml/L for dried beans, and 51.17 ml/L for fresh fruit. The lethal concentration LC100 for mosquito fish (Gambusia affinis Baird and Gerard) was 2.08 ml/L for fresh extract and 1.71 ml/L for dried extract, while LC50 on the 24-hour basis was 0.88 ml/L for fresh extract, and 0.35 ml/L for dried extract.