敌百虫对水丝蚓的毒害

采用急性毒性方法测定了被不同浓度敌百虫毒害的水丝蚓(Limnodilus hoffineisteri)半致死浓度(LC50),利用测定酶活性方法检测了水丝蚓超氧化物歧化酶(SOD)的变化及中毒后水丝蚓喂饲的强壮水螅(Hydra robusta)SOD的改变。(1)敌百虫对水丝蚓48 h LC50为3.29 mg/L。敌百虫对水丝蚓SOD活性影响显著(P<0.05):在低浓度1~4 mg/L时,SOD活性呈上升趋势,但随浓度增加至5 mg/L,SOD活性开始下降。(2)用1~8 mg/L中毒后的水丝蚓依次喂饲水螅,SOD活性呈上升趋势。实验结果表明,敌百虫作为重要的杀虫剂或作为防治鱼病的药物,对水丝蚓造成胁迫,并在一定浓度范围内直接或间接地影响以其为食的动物的生存,以至危害生命。

The Poisoning of Metriphonate to Limnodilus hoffineisteri

This article describes the poisoning of metriphonate to Limnodilus hoffineisteri.The LC_(50) of metriphonate to L.hoffineisteri was determined,and superoxide dismutase(SOD) changes in L.hoffineisteri and SOD changes in hydra feeding with poisoned L.hoffineisteri were measured.The LC_(50) of metriphonate to L.hoffineisteri was 3.29 mg/L.The SOD activity in L.hoffineisteri was significantly affected by metriphonate(P<0.05).Low concentration(1-4 mg/L) of metriphonate increased SOD activity,while high concentration (5 mg/L) of metriphonate decreased SOD activity.When hydras were fed with L.hoffineisteri which had been poisoned in 1-8 mg/L metriphonate,SOD activity was increased.It is proved that metriphonate,an important insecticide or a drug which is used to prevent fish diseases,threatens the survival of L.hoffineisteri and affects the predators of L.hoffineisteri indirectly.