Monitoring the acute and subacute toxicity effects of herbicide acetochlor by bacterivorous nematode

Much attentions is paid to the toxic side-effect of herbicides on non-target organisms and environmental safety. Nematodes have been considered as an important indicator and widely used in toxicity testing, due to requiring little space, having short life cycles, simple reproduction and being relatively easy manipulated and maintained in laboratory cultures. In our study, the herbicide acetochlor was evaluated for its toxicity effects on Acrobeloides nanus. Endpoints were chosen to compare the toxicity effects of acetochlor on lethality, reproduction capacity and growth of these nematodes. The lethality of the nematode exposed to acetochlor changed with an increasing in exposure time and the exposed concentrations. The LC50 values of A.nanus were 2498.45 mg/L for 24h exposure and 2170.55 mg/L for 48h exposure. This study showed that acetochlor had no long-term effects on nematode reproduction, growth and development at lower concentrations(from 2.5 to 20 mg·L-1 ), While the higher concentrations of acetochlor (from 40 to 160 mg/L) mostly revealed sublethal toxicity to A.nanus.