Effects of Sublethal Exposure of LC50 of 2,4-D on the Reproduction and Development of Earthworm Eutyphoeus waltoni Michaelsen (Oligochaeta:Octochaetidae)

Laboratory tests were conducted to observe the sub-lethal exposure (20% and 60%) of LC₅₀ of herbicide 2,4-D of different feed materials of buffalo dung with agro-wastes of different exposure periods. There was time and dose dependent effect of sub lethal 20% and 60% of LC₅₀ of different feed material of buffalo dung with agro-wastes of different exposure periods on the reproduction and development of earthworm Eutyphoeus waltoni. Sub-lethal (20% and 60%) of LC₅₀ of different exposure periods were observed after treatment of different combination of buffalo dung with agro-wastes. The maximum reduction in clitellum development (days) cocoon production/worm and hatchlings/cocoon as well as survival of hatchlings was observed in the treatment of 20% of 24h LC₅₀ (102.16mg/kg) of buffalo dung with wheat straw and gram bran (BD+Ws+Gb) 20% of 24h LC₅₀ (108.04 mg/kg) of buffalo dung with wheat straw (BD+Ws) and 20% of 24h LC₅₀ (108.08 mg/kg) of buffalo dung with gram bran (BD+Gb) as well as 20% of 24h LC₅₀ (110.02 mg/kg) of buffalo dung respectively on the clitellum development period, cocoon production/worm and hatchlings/cocoon as well as survival of hatchling of Eutyphoeus waltoni, respectively. There was no significant (P<0.05, t-test) difference between control and 20% of LC₅₀ of BD+Ws+Gb of all exposure periods shows that the vermicompost of feed material of this combination was more potential for use in agricultural fields because it enhance the tolerance power of earthworm Eutyphoeus waltoni against herbicide 2,4-D.