Used primarily as a natural pesticide and piscicide, rotenone is effective in controlling insect pests on crops and ornamental plants. It acts by inhibiting cellular respiration in mitochondria, making it toxic to insects, mites, and nematodes. In aquatic management, it is applied to eliminate invasive fish species from lakes and streams due to its ability to quickly impair fish respiration. It has also been used in small amounts in organic farming and in research settings to induce Parkinson's-like symptoms in animal models for neurological studies. Despite its natural origin, it requires careful handling due to toxicity to aquatic life and potential health risks.