不同含量茶皂素对福寿螺的毒杀活性测定

Toxicities of Different Concentrations of Tea Saponins to Pomacea canaliculata

为了找到高效且对环境污染小的福寿螺防治药剂,利用不同来源60%、90%和98%的茶皂素原粉分别配制7种浓度剂液,采用浸杀法测定各剂液对福寿螺的室内毒杀活性。试验结果表明:3种不同来源茶皂素原粉配置的5.000、2.500、1.250、0.625、0.312、0.156、0.078 mg/L茶皂素剂液处理对福寿螺均具有不同程度的毒杀效果,福寿螺死亡率随着浓度的提高和浸杀时间的延长而增加;以5 mg/L茶皂素的效果最好,60%原粉配置的处理浸杀60 h福寿螺死亡率达到100%,而90%、98%原粉配置的处理要浸杀72 h福寿螺死亡率才达到100%;3组试验中,浸杀72 h,5 mg/L茶皂素的毒杀效果(福寿螺死亡率100%)均高于8 mg/L四聚乙醛处理(72.5%~77.5%),而2.5 mg/L茶皂素的毒杀效果(62.5%~67.5%)低于8 mg/L四聚乙醛处理;茶皂素处理剂量过低对福寿螺的室内毒杀效果不佳。通过对72 h处理的毒力回归分析,不同来源60%、90%和98%茶皂素原粉对福寿螺的LC50分别为1.27,1.21和1.37 mg/L。

This study aims to find efficient and environmentally friendly pesticides for the prevention and control of Pomacea canaliculata.The 60%,90%,and 98%raw powder of tea saponins from different sources was prepared into tea saponin agents at seven concentrations(5.000,2.500,1.250,0.625,0.312,0.156,and 0.078 mg/L).The indoor toxicity of each agent to P.canaliculata was determined with the immersion method.The results showed that all the tea saponin agents prepared in this study had toxic effects on P.canaliculata.The mortality rate of P.canaliculata increased with the increases in concentration and immersion time.The tea saponin agent at the concentration of 5 mg/L had the strongest toxicity.The tea saponin agent prepared with 60%raw powder led to a mortality rate of 100%for P.canaliculata after 60 h of immersion,and that prepared with 90%and 98%raw powder achieved a mortality rate of 100%after 72 h of immersion.After immersion for 72 h,5 mg/L tea saponin agent demonstrated higher toxicity(with a mortality rate of 100%)than 8 mg/L metaldehyde(with a mortality rate of 72.5%-77.5%),while 2.5 mg/L tea saponin agent(62.5%-67.5%)demonstrated lower toxicity than 8 mg/L metaldehyde.The tea saponins at low doses demonstrated poor indoor toxicity to P.canaliculata.The regression analysis showed that 60%,90%,and 98%tea saponin raw powder had the median lethal concentrations(LC50)of 1.27,1.21,and 1.37 mg/L,respectively,on P.canaliculata after 72 h of treatment.