久效磷对细小色矛线虫胚胎发育和繁殖的影响

采用平板静态毒性实验方法,研究了久效磷对细小色矛线虫(Chromadorina germanica)的急性毒性及胚胎发育和繁殖的影响,并探讨了其毒性作用机制.结果表明,久效磷对C. germanica 的24,48,96h的LC50分别为66.42,36.94,16.03 μmol/L.对C. germanica繁殖具有显著的抑制作用:1.0μmol/L久效磷暴露组子一代的数量急剧减少,仅为对照组的52.9%,10μmol/L暴露组则完全抑制了产卵和子一代的产生.对C.germanica的胚胎毒性主要表现为胚胎发育时间的延迟:0.1,1.0,10.0μmol/L久效磷暴露组胚胎发育持续时间比对照组的17.05h分别延长了1.24,1.92,1.96h,呈剂量-效应关系,且10.0μmol/L久效磷完全抑制了卵的孵化.久效磷对C. germanica精巢和卵巢超微结构的损伤,导致了精子和卵子质量下降.因此,久效磷导致C.germanica的胚胎发育持续时间的延长和精子、卵子质量下降是其子一代数量急剧减少的主要原因之一.

Effect of monocrotophos on embryonic development and reproduction of a marine nematode Chromadorina germanica

Acute toxicity of monocrotophos on Chromadorina germanica was tested in static culture plate, and effects of monocrotophos on embryonic development and reproduction were also studied. LC50 of the 24, 48 and 96 h were 66.42, 36.94, 16.03 μmol/L,respectively. Monocrotophos significantly inhibited the reproduction of C. germanica. When exposed to 1.0 μmol/L monocrotophos, the number of offspring reduced to 52.9% compared with control, while exposed to 10 μmol/L monocrotophos, neither eggs nor offspring were observed. The sharp reduction of the number of offspring might relate to the interruption of embryo development and damage on testis and ovary. After exposure to 0.1, 1.0, 10.0 μmol/L monocrotophos, the development of embryo was delayed for 1.24, 1.92, 1.96 h, respectively, compared with 17.05 h of the control, showing a dose-effect relationship. Exposure to 10.0 μmol/L monocrotophos caused no hatch of embryo. Besides, the ultrastructure of testis and ovary showed great damage under exposure of 10.0 μmol/L monocrotophos. The sharp reduction of the number of offsproing under exposure of monocrotophos might relate to the interruption of embryo development and damage on testis and ovary.