Acute Toxicity of Three Pesticides to Juveniles Allogynogenetic Crucian Carp

The acute toxicity of abamectin-chlorpyrifos,pymetrozine and metaldehyde to Allogynogenetic crucian carp juveniles was determined with a static method by using death probability unit-log of concentration,and the acute toxicity of the three pesticides was evaluated.The result showed that the median-lethal concentrations of abamectin-chlorpyrifos to Alogynogenetic crucian carp juveniles in 24,48,72,96h were 4. 8 × 10- 3,2.5 ×10- 3,1.3 ×10- 3and 1. 2 × 10- 3mg /L,respectively,pymetrozine,445,428,403 and 387 mg /L,respectively,and metaldehyde,728,566,551 and 411 mg /L,respectively. The safe-concentrations of these three pesticides in 96 h were 1. 2 ×10- 4,38.7 and 41.1 mg/L,respectively,and the toxicity of these three pesticides was in order of abamectin-chlorpyrifos pymetrozine metaldehyde in turn.