钟全福

摘要：【目的】明確苦参碱对罗非鱼三代虫的杀灭效果，并分析药物浓度、作用时间及苦参碱与敌百虫配伍对罗非鱼三代虫的联合毒力，为苦参碱在水产养殖中的推广应用提供参考依据。【方法】以浸浴试验测定2.0%苦参碱和90%敌百虫对罗非鱼三代虫的毒力，计算半数致死浓度（LC50）;在此基础上采用交互测定法进行苦参碱与敌百虫配比筛选，通过毒效比和共毒系数（CTC）测定苦参碱与敌百虫配伍对罗非鱼三代虫的联合毒力，并利用安全浓度（SC）和药物毒性蓄积程度系数（MAC）评价苦参碱—敌百虫复合制剂对罗非鱼苗种的安全性。【结果】2.0%苦参碱对罗非鱼三代虫有较强的杀灭能力，对应的24、48、72 h的LC50分别为1.305、0.843和0.562 mg/L;2.0%苦参碱与90%敌百虫按质量比7∶5配伍时毒效比最高（1.54），其对罗非鱼三代虫24、48、72 h的LC50分别为0.433、0.353和0.232 mg/L，对应的CTC分别为294.12、207.02和206.22。苦参碱—敌百虫复合制剂（质量比7∶5）对罗非鱼苗种24、48、72 和96 h的LC50分别为28.410、24.494、19.982和17.265 mg/L，SC为1.727 mg/L;MAC在24～72 h期间随浸浴时间的延长而升高，且在48～72 h期间出现最大值（40.485%），在72～96 h期间下降较明显，但均大于0，即苦参碱—敌百虫复合制剂（质量比7∶5）属于低毒级药物制剂。【结论】植物源杀虫剂苦参碱对鱼类三代虫有良好的杀虫活性及较低的鱼类毒性，尤其与敌百虫配伍表现出明显的协同增效作用，既提高药效，又降低驱虫药物的使用剂量和用药成本，且能克服单剂药物易产生抗药性的问题，可在水产养殖生产上推广应用。

关键词： 苦参碱;三代虫;罗非鱼;杀虫效果;共毒系数（CTC）;药物毒性蓄积程度系数（MAC）

Abstract：【Objective】The antiscolic effect of matrine against Gyrodactylus of tilapia was definited， and the drug concentration， action time and combined toxicity of matrine and trichlorfon to Gyrodactylus of tilapia were analyzed， so as to provide reference for the promotion and application of matrine in aquaculture. 【Method】The virulence of 2.0% matrine and 90% dipterex to Gyrodactylus of tilapia was determined by immersion bath test， and the median lethal concentration （LC50） was calculated. On this basis， the synergistic ratio of matrine and dipterex was screened by interactive assay， and the joint virulence of matrine and dipterex against Gyrodactylus of tilapia was determined by effect ratio and co-toxicity coefficient（CTC）， and the safe concentration（SC） and the toxicity accumulation coefficient（MAC） were used to evalua-te the safety of matrine-dipterex compound against tilapia fry. 【Result】The results showed that，2.0% matrine had high antiscolic effect on Gyrodactylus of tilapia， the LC50 of 2.0% matrine on 24， 48 and 72 h were 1.305， 0.843 and 0.562 mg/L， respectively. The toxicity-efficacy ratio was the highest（1.54）， when the mass ratio of 2.0% matrine and 90% dipterex was 7∶5， and the LC50 of the mixed formulation on Gyrodactylus of tilapia at 24， 48 and 72 h were 0.433， 0.353 and 0.232 mg/L， at the same time， the corresponding CTC were 294.12， 207.02 and 206.22. The LC50 of the matrine-dipterex compound on juvenile tilapia at 24， 48， 72 and 96 h were 28.410， 24.494， 19.982 and 17.265 mg/L respectively， and the SC was 1.727 mg/L. MAC increased with the prolongation of immersion time from 24 to 72 h， and reached the maximum va-lue （40.485%） during 48-72 h， and decreased greatly during 72-96 h， but both were greater than 0. That was， the matrine-dipterex compound（mass ratio 7∶5） belonged to low toxic substances. 【Conclusion】The botanical pesticide matrine has high insecticidal efficacy and low toxicity to Gyrodactylus of fish， especially it shows a synergistic effect between matrine and dipterex to control Gyrodactylus. It can not only improve the efficacy， but also reduce the dosage and cost of anthelmintic agent， and overcome the problem of single drug resistance. Therefore， matrine can be widely used in aquaculture.

Key words： matrine; Gyrodactylus; tilapia; antiscolic effect; co-toxicity index（CTC）; toxicity accumulation coe-fficient（MAC）

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