LAUSR

Abstract The present study evaluates the nematicidal, antifungal and insecticidal effects of extracts from different organs (leaves, stems and roots) of Artemisia halodendron Turcz. ex Bess. Correlative analysis revealed that polyacetylenes were the main contributors to biological activities. Furthermore, five extraction techniques were compared and evaluated based on the yield of polyacetylenes and their activities. It was found that microwave-assisted extraction (MAE) was the best extracting approach. Additionally, two new polyacetylenes (1–2) and four known polyacetylenes (3–6) were isolated from the MAE extract. All polyacetylenes showed remarkable nematicidal effect against Meloidogyne incognita (Kofoid & White) Chitwood (50 % lethal concentration, LC50, 0.21–9.46 mg/L) compared with abamectin (LC50, 9.98 mg/L). In particular, nematicidal activity of the new compound 1 was 48-times higher than that of abamectin. Also, these polyacetylenes exhibited antifungal effects against five fungi (minimum inhibitory concentration, MIC, 4–128 mg/L). Moreover, polyacetylenes 1–4 showed remarkable insecticidal activity against Bradysia odoriphaga Yang & Zhang (50 % lethal dose, LD50, 19.31–36.51 mg/L), stronger than the azadirachtin (LD50, 39.30 mg/L). Together, the results gained from this study suggest that A. halodendron and the isolated polyacetylenes have great potential application in nematicide, fungicide and insecticide agent industry.