中华稻蝗（Oxya chinensis）对重金属镉的累积及排泄

为了研究重金属镉(Cd)在植食性昆虫体内的累积和排泄规律,通过Cd慢性染毒的方法,用不同浓度Cd溶液培养的麦苗饲喂中华稻蝗(从4龄若虫至成虫),采用原子吸收法测定Cd在中华稻蝗(Oxyachinensis)整虫和中肠的蓄积及Cd在其粪便和蜕中的排泄量。研究结果表明,Cd在中华稻蝗整虫和中肠中的累积规律相似,即随着麦苗中Cd含量的增加,整虫和中肠中Cd的累积量明显升高,且各处理间存在显著差异(P<0.05)。部分Cd可以通过粪便的排泄和蜕皮过程而排出体外。用不同Cd浓度的麦苗饲喂中华稻蝗后,其粪便和蜕中的Cd排泄量与对照组相比显著升高(P<0.05),且各处理间差异显著(P<0.05)。中华稻蝗整虫、中肠、粪便和蜕中的Cd含量与食物(麦苗叶片)中的Cd含量存在显著的剂量-反应关系,其相关系数分别为:整虫0.977、中肠0.920、粪便0.967、蜕0.840。研究结果可为进一步研究Cd在中华稻蝗体内积累和排泄的动态变化规律提供理论和实验依据。

A(c)cumulation and Excretion of Cadmium in Oxya chinensis Fed on Treated Diets with Cadmium

In order to study the accumulation and excretion of heavy metal in insects,cadmium amounts in the whole body,midgut,feces,and exuviaes of Oxya chinensis fed on diets contaminated Cd were detected using an atomic absorption spectrometer.The results showed that the Cd accumulation characteristics in the whole body and midgut were similar.The accumulated Cd concentrations in the whole body and midgut rose with the increase of Cd content in the treated diets(wheat seedlings) and showed significant difference(P<0.05).Some of Cd in diets could be excreted through feces and exuviaes.The Cd excretion in the feces and exuviaes of O.chinensis fed on treated diets increased markedly comparing to the control treatment(P<0.05).There were statistically significant differences in Cd excretion between different treatments(P<0.05).There were significant dose-dependent relationships between Cd accumulated in the grasshopper,O.chinensis and Cd content in diets.The correlation coefficients were 0.977 for whole body,0.920 for midgut,0.967 for feces,and 0.840 for exuviaes,respectively.The results might provide insight into the dynamic variation of Cd accumulation and excretion in the grasshopper O.chinensis.