Toxicities of Different Concentrations of Tea Saponins to Pomacea canaliculata
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.
NETL
NSTL
万方数据
