UTTAR PRADESH JOURNAL OF ZOOLOGY

Earthworms constitute a significant portion of the biomass in soil. They serve as appropriate bioindicators for chemical pollution. The impact of chemicals on earthworms varies based on the substances used, but regardless of their nature, both the direct and indirect effects on soil organisms must be included in the ecological risk evaluation. Chlorantraniliprole (CAP) is widely used to control agricultural pests, but also affects non-target organisms like earthworms. The present laboratory study was conducted to observe whether the insecticide is toxic or not to earthworms by carrying out the following studies: Determination of LC₀, LC₅₀ and LC₁₀₀ values; observation of biomass L. mauritii after exposure to sublethal concentration of Chlorantraniliprole and enumeration of bacterial and fungal population in gut contents. For the acute toxicity study, mortality of L. mauritii was observed after 24, 48, 72, 96 and 120 h of CAP exposure.  Sub-lethal concentrations of CAP were selected from 96 hr LC50 value of 10.22 mlKg^-1 (5.11, 2.04, 1.46 and 1.022 mlKg^-1). Biomass of L. mauritii was observed once in 10 days up to 90 days. 10 a clitellate L. mauritii was introduced into each experiment (C, T1, T2, T3 and T4). Soil substrate without CAP served as control. The present study showed that CAP highly affected the biomass and gut microbial population of L. mauritii.  These findings proved that CAP application in the agricultural field highly inhibited earthworm population in soil so we could lost our soil fertility in future.