3种植物次生代谢物质对舞毒蛾生长发育的影响

Effects of Three Plant Secondary Metabolites on Growth and Development of Lymantria dispar

通过生物测定、拒食活性测定和酶活测定试验,分析了3种植物次生代谢物质对舞毒蛾3龄幼虫的毒杀、拒食效果及其保护酶CAT、SOD活性的影响。试验结果表明:苦参碱、氧化苦参碱和山奈酚对舞毒蛾幼虫均具有良好的毒杀和拒食活性。其中,苦参碱杀虫效果最好,质量浓度为2.000 mg/mL的苦参碱对幼虫72 h死亡率达到71.67%,而山奈酚拒食效果最强,1.000 mg/mL时对幼虫72 h拒食率达到70.53%;离体酶活试验发现,苦参碱和氧化苦参碱对离体CAT、SOD活性均有较强的抑制作用;而低浓度的山奈酚则可以激活2种保护酶的活性;体内酶活试验显示,3种植物次生代谢物质对幼虫体内CAT、SOD活性的抑制作用会随着处理后时间的延长而减弱,其中苦参碱和氧化苦参碱处理组的2种保护酶活性均呈现先减小后增大的趋势,在处理后48 h活性达到最低并显著低于同时期对照组(P<0.05),而山奈酚处理组CAT活性则呈现出先增大后减小的趋势。

In this study, the effects of three plant secondary metabolites on two protective enzymes （ CAT and SOD） of Lymantria dispar were analyzed by bioassay, in vitro and in vivo enzyme activity assay and antifeedant activity assay. The results indicated that matrine, oxymatrine and kaempferol all possessed a highly insecticidal and antifeedant activity on 3rd instar larvae of L. dispar, among which matrine had the strongest insecticidal activity, and the insecticidal rate reached 71.67% at 2.000 mg/mL, while kaempferol had the strongest antifeedant activity, and the antifeedant rate reached 70.53% at 1.000 mg/mL. In vitro enzyme activity tests showed that activities of CAT and SOD were both inhibited by matrine and oxymatrine, while two protective enzymes were activated by kaempferol at a low concentration. In vivo enzyme activity assays indicated that with the increase of treatment time, the inhibition of three kinds of plant secondary metabolites to CAT and SOD activi-ties of larvae was weakened, protective enzyme activities of matrine and oxymatrine treatment groups both showed a first decreasing and then increasing tendency, moreover, the activities reached the lowest at 48 h after treatment and was significantly lower than that of the control group （P〈0.05） ; The activities of kaempferol treatment groups showed a first increasing and then decreasing tendency.