Toxicity of soil accumulated insecticides on the survival of Isotoma decorata (Brown, 1923) in laboratory

Abstract

Toxicity of 10 insecticides was tested against Isotoma decorata under laboratory conditions by incorporating field recommended doses (RDs) of insecticides along with three lower doses (1/2 × RD, 1/4 × RD, and 1/6 × RD) in the soil. The survival of I. decorata was observed every week for eight weeks. Results showed that endosulfan, chlorpyrifos, chlorfenapyr, imidacloprid, and acetamiprid were the most toxic insecticides at all tested doses with significantly less survived springtails. Comparatively, higher survival was observed after treatment with bifenthrin, pyriproxyfen, emamectin benzoate, and spinosad. In comparison, cypermethrin showed significantly less toxicity with the highest survival of I. decorata compared with all other tested insecticides. RDs of all these insecticides were found hazardous for the survival of I. decorata. At the RDs of chlorpyrifos and endosulfan survival of I. decorata was <1%. A decline in the survival rate of springtail was observed against these insecticides at all doses with an increased time of exposure during the eight weeks. Results showed the effects of insecticides on non-target soil springtails and implied the caution and possible mitigation measures using these insecticides.