title: Insecticidal Potential of Clove Essential Oil and Its Constituents on Cacopsylla chinensis (Hemiptera: Psyllidae) in Laboratory and Field.
abstract: Cacopsylla chinensis (Yang and Li) (Hemiptera: Psyllidae) is an important pest of pear in China. As an alternative to conventional chemical pesticides, botanicals including essential oils and their constituents could provide an eco-friendly and nonhazardous control method. In this study, the essential oil of clove buds (Syzygium aromaticum) was obtained by hydrodistillation. Five constituents, accounting for 99.89% of the oil, were identified by gas chromatography-mass spectrometry, and the major constituents were eugenol (88.61%) and eugenol acetate (8.89%), followed by β-caryophyllene (1.89%). In a laboratory bioassay, clove essential oil, commercial eugenol (99.00%) and β-caryophyllene (98.00%) exhibited strong contact toxicity against the summerform adults of C. chinensis with LD50 values of 0.730, 0.673, and 0.708 µg/adult, and against the nymphs with LD50 values of 1.795, 1.668, and 1.770 µg/nymph, respectively. In contrast, commercial eugenol acetate (98%) had LD50 values of 9.266 µg/adult and 9.942 µg/nymph. In a field trial, clove essential oil caused significant population reductions of 73.01% (4.80 mg/ml), 66.18% (2.40 mg/ml) and 46.56% (1.20 mg/ml), respectively. Our results demonstrated that clove essential oil and its constituents have potential as a source of natural insecticides.
authors.affiliation: Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, 100193, China.
authors.forename: Bao-Liang
authors.initials: BL
authors.lastname: Tian
authors.forename: Qi-Zhi
authors.initials: QZ
authors.lastname: Liu
authors.affiliation: Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, 100193, China.
authors.forename: Zhi-Long
authors.initials: ZL
authors.lastname: Liu
authors.affiliation: Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, 100193, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.affiliation: Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, 100193, China.
authors.forename: Jie-Wen
authors.initials: JW
authors.lastname: Wang
mesh_terms: D000818:Animals; D045783:Clove Oil; D006430:Hemiptera / Q000254:growth & development; D007306:Insecticides; D007928:Lethal Dose 50; D009758:Nymph / Q000254:growth & development
chemical_list: D045783:Clove Oil; D007306:Insecticides
keywords: Syzygium aromaticum; contact toxicity; eugenol; pear psylla