92种野生和栽培植物或中草药的提取物杀灭钉螺筛选试验

PRELIMINARY SCREENING TESTS OF MOLLUSCICIDAL EFFECTS OF EXTRACTS FROM 92 SPECIES OF WILD OR CULTIVATED PLANTS AND CHINESE HERBS AGAINST ONCOMELANIA HUPENSIS

目的 评估某些野生或栽培植物与中草药提取物的杀螺效果 ,筛选植物源灭螺药。方法 样品的提取分别采用热水抽提、有机溶剂提取和水与有机溶剂混合相提取法。室内浸泡法进行提取物的杀螺效果初筛试验 ;菜籽饼提取物小规模现场试验采用浸泡法。结果 用浓度为 10 0 mg/L的源自油菜、知母、决明、鱼眼菊、土茯苓等 5种植物的提取物浸杀钉螺 48h(2 5℃ ) ,死亡率为 92 .8%-10 0 % ;土牛膝、川乌、醉鱼草、商陆等 40种植物的提取物 ,在浓度为 5 0 0 mg/L 或 10 0 0 mg/L、浸泡 48h(2 5℃ )条件下 ,钉螺死亡率为 5 0 % -10 0 % ;其余 47种植物的提取物在浓度为 5 0 0 mg/L 或10 0 0 mg/L、浸泡 48h(2 5℃ )条件下 ,钉螺死亡率均小于 49%。菜籽饼提取物粗品在浓度为 10 0 0mg/L下 ,小规模现场浸泡 2 4、48h和 72 h,钉螺死亡率分别为 18%、84%和 92 % ,同样试验条件下未出现试验鱼苗死亡。结论 获得了 5种具有较高杀螺效果的候选植物 。

Objective To evaluate the molluscicidal effects of extracts from some wild or cultivated plants and Chinese herbs against Oncomelania snail for screening of the plant molluscicides Methods Ninety two species of plant materials(roots, stems, leaves, fruits and flowers or seeds) were dried for 6 8 h at 70℃ and pulverized. Active ingredients of the samples were extracted using organic solvents or hot water by the water bath reflux method. Immersion method was adopted in the molluscicidal screening tests of both in laboratory and in small scale field. Results The laboratory test showed that the extracts from five species of plants killed 92 8%-100% of Oncomelania snails for 48 h exposure at a concentration of 100 mg/L; the extracts from 40 species had snail mortalities of 50%-100% for 48 h at concentrations of 500 mg/L or 1000 mg/L; the extracts from other 47 species had less than 49% mortalities of the snails for 48 h at the concentrations of 500 mg/L or 1000 mg/L. The small scale field trial indicated that extract from rapeseed cake killed 18%, 82% and 86% of the snails exposed for 24 h, 48 h and 72 h at a concentration of 1000 mg/L, respectively, but it did not kill young carp at the same exposure time and the same concentration. Conclusion Five species of plant as candidate molluscicides were screened out, of which rapeseed cake from Brassica napus could be a valuable resource for the development of plant molluscicides.