Anti-termitic activities of essential oils from coniferous trees against Coptotermes formosanus.
In this study, the anti-termitic activities of 11 essential oils from three species of coniferous tree against Coptotermes formosanus Shiraki were investigated using direct contact application. Results demonstrated that at the dosage of 10 mg/g, the heartwood and sapwood essential oils of Calocedrus macrolepis var. formosana and Cryptomeria japonica and the leaf essential oil of Chamaecyparis obtusa var. formosana had 100% mortality after 5 d of test. Among the tested essential oils, the heartwood essential oil of C. macrolepis var. formosana killed all termites after 1 d of test, with an LC(50) value of 2.6 mg/g, exhibiting the strongest termiticidal property. The termiticidal effect of heartwood essential oil was due to its toxicity and its repellent action.
Cheng
Sen-Sung
SS
School of Forestry and Resource Conservation, National Taiwan University, Taipei 106, Taiwan.
Chang
Hui-Ting
HT
Wu
Chi-Lin
CL
Chang
Shang-Tzen
ST
D000818:Animals; D029780:Chamaecyparis / Q000737:chemistry*; D032485:Cryptomeria / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D007306:Insecticides / Q000737:chemistry / Q000494:pharmacology; D020049:Isoptera / Q000187:drug effects*; D010938:Plant Oils / Q000737:chemistry / Q000494:pharmacology*; D013997:Time Factors; D014934:Wood / Q000737:chemistry
D007306:Insecticides; D010938:Plant Oils