铜、镉胁迫对舞毒蛾排毒代谢酶的影响

为了探讨重金属铜、镉污染胁迫下舞毒蛾体内排毒代谢酶活性的变化,本文以3种不同质量分数的铜(Cu,400、700、1 000 mg/kg)、镉(Cd, 1.0、3.0、6.0 mg/kg)处理土壤,用处理后的土壤盆栽1年生小黑杨扦插苗,研究舞毒蛾体内排毒代谢酶活性的变化趋势。结果发现,Cu、Cd不同浓度处理的杨树对舞毒蛾3龄、4龄幼虫体内排毒代谢酶活性有显著的干扰作用。与对照组相比,中、高质量分数Cu、Cd处理组3龄幼虫体内SOD、ACP和AKP酶活性显著降低(P0.05),低质量分数Cu、Cd处理组下降不显著(P0.05)。而POD和GSTs酶活性变化恰恰相反,中、高质量分数Cu、Cd处理组舞毒蛾3龄幼虫体内POD和GSTs酶活性显著升高(P0.05),低质量分数Cu、Cd处理升高不显著(P0.05)。中、高质量分数Cu、Cd处理下,4龄幼虫体内SOD、POD、ACP、AKP和GSTs酶活性和对照组相比显著降低(P0.05),低质量分数重金属处理和对照组相比下降不显著(P0.05)。以上结果显示,中、高质量分数Cu、Cd胁迫能显著干扰舞毒蛾幼虫的排毒代谢,且随着幼虫由3龄到4龄的发育,最终均表现为显著的抑制作用;低质量分数Cu、Cd胁迫对舞毒蛾幼虫排毒代谢干扰作用不显著。 

Effects of copper and cadmium stress on the activities of detoxifying metabolic enzymes in Lymantria dispar

In order to investigate the changes of detoxification metabolic activity in gypsy moth (Lymantria dispar) under the heavy metal pollution stress, we measured the detoxifying metabolism in gypsy moth body feeding on one-year potted seedlings of Populus simonii×P. nigra after treating the soil with three concentrations of copper (Cu, 400, 700, 1 000 mg/kg) and cadmium (Cd, 1.0, 3.0, 6.0 mg/kg). The results showed that Cu and Cd had a significant impact on the detoxification metabolic enzyme in the third and fourth instar larvae. The activities of SOD, ACP and AKP enzymes in vivo in the third instar larvae at medium and high concentrations of Cu and Cd were lower than the control group (P0.05),but at the low concentrations of Cu and Cd, the difference was not obvious (P0.05). The change of activities of POD and GSTs was just the opposite. The activities of POD and GSTs enzymes in the third instar larvae at medium and high concentrations of Cu and Cd increased significantly (P0.05), but not obvious (P0.05) at the low concentrations of Cu and Cd. The activities of SOD, POD, ACP, AKP and GSTs enzymes in the fourth instar larvae at medium and high concentrations of Cu and Cd decreased significantly (P0.05),but not obvious at the low concentrations of Cu and Cd treatment (P0.05). These results showed that the high levels of Cu and Cd stress could significantly interfere with the metabolic detoxification of gypsy moth larvae, and with the third instar larvae developing into the fourth instar, the heavy metal stress finally showed a significant inhibition to the development of larvae, while low levels of Cu and Cd stress had not significant interference with metabolic detoxification of the larvae.