Abstract: 【Aim】 In view of the scarcity of botanical pesticide products for controlling thrips pests, the aim of this study is to evaluate the insecticidal activity of plant materials against thrips so as to lay a foundation for the development of botanical pesticide products. 【Methods】 The fumigation activities of 126 plant essential oils or main components of essential oils against Anaphothrips obscurus were evaluated by triangle bottle fumigation method. 【Results】 Ten plant essential oils or main components of essential oils showed high fumigation activity against both the 2nd instar nymphs and adults of A. obscurus, with the fumigation toxicity in the descending order as follows: wintergreen oil, oregano oil, cinnamon oil, thyme oil, citral, sassafras oil, perilla leaf oil, garlic oil, dipentene, and terpineol. The LC₅₀ values of the wintergreen oil against the 2nd instar nymphs and adults were 0.97 and 2.56 μL/L, respectively, while those of the oregano oil were 1.47 and 3.27 μL/L, respectively. At the LC₉₅ dose, the LT₅₀ values of the 10 plant essential oils against A. obscurus adults in the ascending order were sassafras oil, citral, terpineol, dipentene, oregano oil, wintergreen oil, thyme oil, cinnamon oil, perilla leaf oil and garlic oil. The LT₅₀ value of the sassafras oil against A. obscurus adults was 17.31 min, with the fastest fumigation effect. 【Conclusion】 The wintergreen oil, oregano oil and sassafras oil exhibit high fumigation activity against A. obscurus, have the application potential and are worth further research.

Key words: Anaphothrips obscurus, essential oil, insecticidal activity, wintergreen oil, oregano oil, sassafras oil