Insecticidal activity of garlic essential oil and their constituents against the mealworm beetle, Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae)

Made available in DSpace on 2018-11-26T17:28:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-04-20 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) This study evaluated the insecticidal activity of garlic, Allium sativum Linnaeus (Amaryllidaceae) essential oil and their principal constituents on Tenebrio molitor. Garlic essential oil, diallyl disulfide, and diallyl sulfide oil were used to compare the lethal and repellent effects on larvae, pupae and adults of T. molitor. Six concentrations of garlic essential oil and their principal constituents were topically applied onto larvae, pupae and adults of this insect. Repellent effect and respiration rate of each constituent was evaluated. The chemical composition of garlic essential oil was also determined and primary compounds were dimethyl trisulfide (19.86%), diallyl disulfide (18.62%), diallyl sulfide (12.67%), diallyl tetrasulfide (11.34%), and 3-vinyl-[4H]-1,2-dithiin (10.11%). Garlic essential oil was toxic to T. molitor larva, followed by pupa and adult. In toxic compounds, diallyl disulfide was the most toxic than diallyl sulfide for pupa > larva > adult respectively and showing lethal effects at different time points. Garlic essential oil, diallyl disulfide and diallyl sulfide induced symptoms of intoxication and necrosis in larva, pupa, and adult of T. molitor between 20-40 h after exposure. Garlic essential oil and their compounds caused lethal and sublethal effects on T. molitor and, therefore, have the potential for pest control. Univ Fed Vicosa, Inst Ciencias Agr, BR-38810000 Rio Paranaiba, MG, Brazil Univ Fed Vicosa, Dept Entomol, BR-36570000 Vicosa, MG, Brazil Univ Fed Vicosa, Dept Quim, BR-36570000 Vicosa, MG, Brazil Univ Estadual Paulista, Dept Protecao Plantas, Escola Ciencias Agron, BR-18603970 Botucatu, SP, Brazil Univ Fed Vales Jequitinhonha & Mucuri, Dept Agron, BR-39100000 Diamantina, MG, Brazil Univ Fed Vicosa, Dept Biol Geral, BR-36570000 Vicosa, MG, Brazil Univ Estadual Paulista, Dept Protecao Plantas, Escola Ciencias Agron, BR-18603970 Botucatu, SP, Brazil