Evaluation of the Bio-Insecticidal Effect of Ricinus communis (Malpighiales: Euphorbiaceae) on the Larvae of Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae)

Abstract

Since chemical insecticides favor the emergence of resistance and have disastrous consequences for the environment, we became interested in an alternative control method against Spodoptera frugiperda, more respectful for the environment. We therefore evaluated the effectiveness of the bio-insecticidal effects of plants extracts and oil of castor against the fall armyworm in the laboratory. The laboratory bioassays consisted of evaluating the toxicity of the castor plants extracts and oil by contact and ingestion on fourth instar larvae of Spodoptera frugiperda using a leaf dipping method. It emerges from this study that the mortality of the larvae treated with the bio-insecticide and the control solution varies significantly and that the mortality rate was 100% for dose 1; 85% for dose 2 and 70% for dose 3. The mortality rate for the control solution is 10%. These results testify to the good larvicidal activity of the organic insecticide based on oil, leaves and unripe seeds of castor bean on the fall armyworm.

Activity of Methanolic and Hydrolyzed Methanolic Extracts of Ricinus communis (Euphorbiaceae) and Kaempferol against Spodoptera frugiperda (Lepidoptera: Noctuidae)

“…R. communis is a plant which is native to Africa and distributed worldwide, from which various compounds have been isolated, including fatty acids, coumarins, alkaloids, terpenoids, and flavonoids [23,24]. Notably, ricin from the group of alkaloids and the compounds kaempferol-3-O-beta-Drutinoside and kaempferol-3-O-beta-D-xylopyranose from the group of flavonoids have been shown to possess insecticidal and insectistatic potential in a large number of insects, as in the case of S. frugiperda [25][26][27]. The insecticide activity of pesticides is mostly due to the inhibition of the acetylcholinesterase enzyme, causing an interruption in the transmission of nerve impulses which leads to muscle convulsions, paralysis, and poisoning by an acetylcholine excess [28,29].…”