Insecticidal potential of cardamom and clove extracts on adult red palm weevil Rhynchophorus ferrugineus

Abstract

Toxicity of cardamom and clove seed powder and extracted compounds against the red palm weevil, Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae), was assessed in laboratory exposure experiments. The treatments comprised different amounts of seed powder of cardamom (0.8, 1, 3, and 5 mg) and clove (1, 3, 5, 7 mg), and extract concentrations (0.2, 0.4, 0.5, 0.6, 0.7, and 0.8) for both plants using ether petroleum or chloroform. Data showed that 5 mg of cardamom powdered seed resulted in 93% mortality after one day and 100% mortality after two days. Whereas after two days, lower amounts (0.8, 1, and 3 mg) resulted in 26%, 40%, 46%, respectively. A similar result was obtained for clove seed powder, where 7 mg caused 53% mortality after one day and 100% mortality after three days, other amounts (1, 3, and 5 mg) resulted in 33%, 73%, and 80%, mortality respectively, after three days. We found that all amounts of extract of both plants resulted in 100% mortality after three days. GC-MS analysis of the cardamom and clove extracts revealed the presence of a large number of terpenes of particular note was eugenol and two novel compounds Hydroxy-alpha-Terpenyl Acetate and Labda -8(17),13(E)- Diene- 15. The current work aims at the possibility of benefiting from natural plants pesticides as being safer as well as on the separation of volatile oils, which was known to be important in the control pests. Keywords: Cardamom, Clove, Rhynchophorus ferrugineus, Terpenes, Hydroxy-alpha-Terpenyl acetate, Labda-8(17), 13(E)-diene-15