Abstract: 【Aim】 This study aims to determine the insecticidal activity of the ethanol extract from Curcuma longa roots against Aphis craccivora adults, to identify the structure of the active compounds, and to evaluate the control effect of the active compound against this insect so as to establish basic data for its application in a botanical pesticide. 【Methods】 Insecticidal compounds were isolated and purified from the extract of C. longa roots with activity-guided fractionation by extraction, silica gel column chromatography, thin layer chromatography and Sephadex LH-20 column chromatography, and their structures were identified based on NMR (nuclear magnetic resonance) and MS (mass spectrometry) data. The insecticidal activities of the extract and the active compounds against apterous adults of A. craccivora were evaluated by dipping method and topical application, respectively. 【Results】 The 95% ethanol extract of C. longa roots had an contact activity against the apterous adults of A. craccivora, with the LC₅₀ value of 3 226.27 mg/L at 24 h after treatment. The active compound (+)-(S)-ar-turmerone isolated from the extract of C. longa roots exhibited good contact activity against the apterous adults of A. craccivora, with the LC₅₀ value of 706.10 mg/L at 24 h after treatment. 【Conclusion】 The 95% ethanol extract of C. longa roots has certain insecticidal activity against A. craccivora adults, and (+)-(S)-ar-turmerone is the main active compound.

Key words: Curcuma longa, root, Aphis craccivora, (+)-(S)-ar-turmerone, insecticidal compounds, insecticidal activity