Potential effects of essential oil from Zanthoxylum limonella seeds against Tribolium castaneum (Coleoptera: Tenebrionidae)

Essential oils of plants with insecticidal properties have been considered as replacements for synthetic chemical pesticides to combat and control insect pests. The chemical composition of the essential oil from dried seeds of Zanthoxylum limonella Alston was determined by the Gas Chromatograph-Mass Spectrometry technique. Insecticidal activity was investigated on Tribolium castaneum Herbst using impregnated filter paper with six concentrations of essential oil at 0, 1, 2, 3, 4, and 5% for adults and larvae mortality tests, and 0, 2, 4, 6, 8 and 10% for egg mortality. All experiments were performed under completely randomized design (CRD) with four replications at 30±5°C and 70±5% relative humidity in 16:8 hours light/dark cycle. A total of 83 components were identified. The principal compounds in the essential oil of Z. limonella were beta-pinene (19.65%), 9-octadecanone (18.80%), D-limonene (9.76%), alpha-fenchene (8.48%), p-mentha-1,5,8-triene (7.16%), 1,8-cineole (6.88%), gamma-terpinene (5.46%), terpinen-4-ol (3.81%), linalool (2.73%), alpha-thujene (1.34%), decanal (1.32%), alpha-phellandrene (1.20%) and linalyl propionate (1.13%). Insecticidal activity presented that 5% of essential oil had the highest effect against T. castaneum at 120 h for adults and 48 h for larvae, while 10% of essential oil at 14 days obtained 100% mortality against eggs of T. castaneum. Results indicated that the essential oil of Z. limonella from dried seeds showed potential for use in the control of T. castaneum