Abbas Khani, Javad Asghari
Journal of Insect Science 12 (73), 1-10, (1 July 2012) https://doi.org/10.1673/031.012.7301
KEYWORDS: fumigant toxicity, gas chromatography-mass spectrometry, mono terpenoids
Essential oils extracted from the foliage of Mentha longifolia (L.) (Lamiales: Lamiaceae) and Pulicaria gnaphalodes Ventenat (Asterales: Asteraceae), and flowers of Achillea wilhelmsii C. Koch (Asterales: Asteraceae) were tested in the laboratory for volatile toxicity against two storedproduct insects, the flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) and the cowpea weevil, Callosobruchus maculatus F. (Coleoptera: Bruchidae). The chemical composition of the isolated oils was examined by gas chromatography-mass spectrometry. InM longifolia, the major compounds were piperitenon (43.9%), tripal (14.3%), oxathiane (9.3%), piperiton oxide (5.9%), and d-limonene (4.3%). In P. gnaphalodes, the major compounds were chrysanthenyl acetate (22.38%), 2L -4L-dihydroxy eicosane (18.5%), verbenol (16.59%), dehydroaromadendrene (12.54%), β-pinen (6.43%), and 1,8 cineol (5.6%). In A. wilhelmsii, the major compounds were 1,8 cineole (13.03%), caranol (8.26%), alpha pinene (6%), farnesyl acetate (6%), and p-cymene (6%). C maculatus was more susceptible to the tested plant products than T castaneum. The oils of the three plants displayed the same insecticidal activity against C. maculatus based on LC50 values (between 1.54µl/L air in P. gnaphalodes, and 2.65 µl/L air in A. wilhelmsii). While the oils of A. wilhelmsii and M. longifolia showed the same strong insecticidal activity against T. castaneum (LC50 = 10.02 and 13.05 µl/L air, respectively), the oil of P. gnaphalodes revealed poor activity against the insect (LC50 = 297.9 µl/L air). These results suggested that essential oils from the tested plants could be used as potential control agents for stored-product insects.