Toxicity of some terpenoids of essential oils of Xylopia aethiopica from Cameroon against Sitophilus zeamais Motschulsky

Abstract

Abstract:The acute toxicity of essential oils from the whole fruit (EF) or from the fibres of the fruit (FF) of the local aromatic plants Xylopiα αethiopicα Dunal (Annonaceae) collected in north Cameroon was evaluated on Sitophilus zeαmαis adults. A concentration of 1 ml of essential oil per 100 g of maize seeds was tested to determine weevil mortality after 24 h of exposure. Under these conditions, the essential oil derived from both EF and FF of X. αethiopicα led to 100% mortality. In a second step, proportions of active compounds present in the oil of both EF and FF of X. αethiopicα were quantified. The toxicity of the four main compounds was tested against S. zeαmαis: α-pinene, β-pinene, ∆-3-carene and terpinen-4-ol according to their proportion in the essential oil of the concerned plant part. β-pinene and terpinen-4-ol were responsible for 50% of the mortality at the proportion found in EF and FF essential oils respectively. When mixed, a synergic effect of the compounds was observed that restored the mortality percentage observed for the crude oil. It appears that X. αethiopicα essential oil could be a potential source of natural and low-cost insecticide to control storage pests.

Bioactivity of Peumus boldus Molina, Laurelia sempervirens (Ruiz & Pav.) Tul. and Laureliopsis philippiana (Looser) Schodde (Monimiacea) essential oils against Sitophilus zeamais Motschulsky

“…Once in the laboratory, only mature and whole leaves were washed with distilled water and dehydrated at 40 °C in a stove (Memmert Gmbh, UNB 500, Schwabach, Germany). The essential oils were obtained by steam distillation during 4 h using distilled water in a Clevenger type apparatus (Kouninki et al, 2007). Subsequently, the oil was treated with sodium sulfate to eliminate water traces and stored in amber-colored glass containers at 4.5 °C.…”

“…The methodology of Kouninki et al (2007) was followed and consisted of 6-mL test tubes treated with 1 mL of a solution of essential oil in acetone, at the required concentration. Then, the tubes were shaken for 1 min to allow the oil to cover the inner surface.…”

Toxicidade por fumigação, contato e ingestão de óleos essenciais para Sitophilus zeamais Motschulsky, 1885 (Coleoptera: Curculionidae)

“…(Huang & Ho, 1998); folhas frescas de T. nocturnum, que apresentou CL 50 de 1321,6 ng/g de grãos de milho (Fazolin et al, 2007a); Vernonia amygdalina Del. (Compositae) e Xylopia aethiopica (Dunal) (Annonaceae), respectivamente (Asawalam & Hassanali, 2006;Kouninki et al, 2007).…”

État et perspectives de lutte contre <i>Sitotroga cerealella</i> (Olivier, 1789), déprédateur des céréales au Bénin : synthèse bibliographique.

“…Leur activité peut varier en fonction des stades du cycle de vie d'un insecte (RegnaultRoger, 2002). Les composés chimiques responsables des actions sur les ravageurs de stock sont principalement les monoterpènes (1-8 cinéole, l'eugenol, le camphor) à effet insecticide sur la survie de C. maculatus ou S. zeamais (Kouninki et al 2007 ;Noudogbessi et al 2009) ou des alcaloïdes à effet inhibiteur du développement larvaire des ravageurs comme T. castananeum (Ngamo et al 2001). Les recherches menées dans le but d'étudier l'effet insecticide, ovicide et larvicide de certaines plantes aromatiques sur Sitotroga cerealella, un des ravageurs les plus redoutables enregistrées des céréales dans le monde entier sont, à ce jour, peu nombreuses dans la littérature.…”