The effects of insecticide carbofuran on survival and reproduction performance of freshwater cladoceran, Moina macrocopa

Abstract

The effects of carbofuran, a widely-used pesticide in rice fields, towards survival and reproduction performance of freshwater cladocerans, Moina macrocopa were assessed in the laboratory for this study. The 24-hour and 48-hour LC5 o values obtained from acute test were 0.4446 and 0.0730 μg L- 1 respectively, after exposure to carbofuran with concentration ranging from 10 to 0.0391 μg L- 1 ; while the NOEC value for 48-hour was l. lxl0-9 μg L- 1 • For chronic test, the average longevity obtained for 0, 2x10·9 and 2x10-4 μg L- 1 were 12.03, 11.00 and 5.40 days, respectively. The net reproductive rate obtained were 52.10, 11.13 and 5.53 for 0, 2x10·9 and 2x10-4 μg L- 1 respectively. The intrinsic rate obtained for 0, 2x10·9 and 2x10-4 μg L" 1 were 0.51, 0.37 and 0.30 individual per day, respectively. The result demonstrated that carbofuran is toxic to Moina macrocopa at 2x10-4 μg L- 1 and above causing rapid decrease in survival and reproduction performance.