Two alkaloids from the aerial parts of Anisodus tanguticus were isolated by elution through series of gel columns.The alkaloid chemical structures were determined by MS and NMR and the alkaloids were identi-fied as hyoscyamine and scopolamine .Contact toxicities of the two alkaloids on nine species of aphids including Brevicoryne brassicae and Myzus persicae ,and four species of mites including Tetranychus cinnabarinus and T.urticae were measured by topical application and slide dip methods.The results showed that hyoscyamine had higher contact toxicity than scopolamine on Rhopalosiphum padi ,Hyalopterus arundimis ,Aphis crac-civora and A.citricola with LC50 values of 257.863 ,275.459,344.645 and 344.717 mg/L,respectively. However,scopolamine was more effective in controlling A.craccivora and R.padi with LC50 values of311.585 and 392.309 mg/L,respectively.The control pesticide rotenone was most toxic to B .brassicae and Aphis gossypii with LC50 values of 399.542 and 436.124 mg/L,respectively.Contact toxicities of hyoscyamine on the nine species of aphids including B .brassicae were higher than or similar to scopolamine.Compared to rotenone,hyoscyamine and scopolamine were more effective against A.craccivora and R.padi.However,ro-tenone was more effective against B .brassicae ,M.persicae and A.gossypii.For the four species of mites tested (T.truncates ,T.viennensis ,T.urticae and T.cinnabarinus),hyoscyamine and scopolamine had simi-lar effects,which included higher contact toxicities on T.urticae and T.cinnabarinus (LC50 :201.027 -224.172 mg/L)than on T.truncates and T.viennensis (LC50 :257.014-332.698 mg/L).Rotenone was more effective than the two alkaloids against T.truncates and T.viennensis with LC50 values of 196.847 and 224.592 mg/L,respectively.%研究唐古特莨菪中生物碱对农业害虫（螨）的生物活性，可为利用该植物研制新型植物源杀虫（螨）剂提供理论依据。本文采用柱色谱分离法从唐古特莨菪地上部分分离得到2个生物碱类化合物，通过 MS、NMR 确定了其化学结构，分别为莨菪碱、东莨菪碱。采用微量点滴法和玻片浸渍法测定了莨菪碱、东莨菪碱对甘蓝蚜、桃蚜等9种蚜虫和朱砂叶螨、二斑叶螨等4种叶螨的触杀活性。结果表明，莨菪碱对禾谷缢管蚜、桃粉蚜、豆蚜和绣线菊蚜具有较强的触杀作用，LC50值分别为257．863，275．459，344．645和344．717 mg／L。东莨菪碱对豆蚜和禾谷缢管蚜具有较强的触杀作用，LC50值分别为311．585和392．309 mg／L。对照药剂鱼藤酮对甘蓝蚜和棉蚜具有较强的触杀作用，LC50值分别为399．542和436．124 mg／L。对甘蓝蚜等9种蚜虫的触杀作用，莨菪碱强于或与东莨菪碱相当；对豆蚜、禾谷缢管蚜的触杀作用，莨菪碱和东莨菪碱均强于鱼藤酮；对甘蓝蚜、桃蚜和棉蚜的触杀作用，莨菪碱和东莨菪碱均弱于鱼藤酮。莨菪碱和东莨菪碱对截形叶螨、山楂叶螨、二斑叶螨和朱砂叶螨具有较强的触杀作用。2种生物碱对4种叶螨的毒力相当，对二斑叶螨和朱砂叶螨的毒力（201．027～224．172 mg／L）均高于截形叶螨和山楂叶螨（257．014～332．698 mg／L）。对照药剂鱼藤酮对截形叶螨、山楂叶螨的 LC50值分别为196．847和224．592 mg／L，其毒力高于莨菪碱和东莨菪碱。
展开▼
