Using plants as pesticides

Using plant material to control pests may alleviate the burden of heavy reliance on synthetic pesticides. In China, the rich tradition and knowledge of herbal medicine, combined with an organized but short-lived effort of using indigenous pesticidal plants, resulted in an accumulation of literature in the late 1950s. 267 pesticidal plants, compiled in a paper in Economic Botany, provide a glimpse of the Chinese experience.

The African soapberry plant Phytolacca dodecandra, traditionally cultivated in many parts of the continent as a laundry soap and shampoo, contains a molluscicide (snail-killing agent). The berries of the plant, known in Ethiopia as endod, are lethal to most species of snails. This discovery offers a potentially low-cost agent in the control of snail-borne diseases like schistosomiasis, or sleeping sickness (affecting 200 million people in Africa, Asia and Latin America and causing 200,000 deaths every year), liver-fluke in animals, onchocerciasis (river blindness) and guinea worm infections. Toxicological studies have proved the plant safe for humans and other animals and plants; WHO has approved extensive field trials.