甲氧虫酰肼对舞毒蛾幼虫保护酶活性的影响

摘要

测定甲氧虫酰肼(RH-2485)对舞毒蛾幼虫保护酶活性的影响.结果表明:舞毒蛾2龄、4龄、6龄幼虫经甲氧虫酰肼处理后,其体内的酚氧化酶(PO)、超氧化物歧化酶(SOD)的活性均先被诱导后被抑制.甲氧虫酰肼对舞毒蛾4龄、6龄幼虫体内过氧化物酶(POD)也表现为先诱导后抑制的作用,其中在处理24h时,对该酶的诱导作用最强,分别为同期对照的1.603,1.805倍;处理48h后,对该酶的抑制作用最强,分别为同期对照的0.858,0.608倍,差异均极显著(P＜0.01);但对2龄幼虫休内该酶具有明显的抑制作用,其中在处理24h后,对该酶的抑制作用最强,为同期对照的0.541倍,差异极显著(P＜0.01).甲氧虫酰肼对舞毒蛾幼虫体内几丁质酶也存在影响,其中对2龄幼虫体内该酶具有先诱导后抑制作用,对4龄、6龄幼虫体内该酶具有明显抑制作用.因此,甲氧虫酰肼能有效干扰舞毒蛾幼虫正常的生理代谢,从而起到毒杀作用.%In order to study the insecticidal activity and mechanism of methoxyfenozide ( RH-2485 ) , this paper measured effects of the chemical on the activities of protective enzymes in the larvals of Lymantria dispar. The results showed that the activities of phenoloxidase (PO) and superoxide dismutase( SOD) in the larvae treated with methoxyfenozide were first induced, and then inhibited. The activities of peroxidase ( POD) was different at different instar of larvals in response to treatment of methoxyfenozide. The activities of POD in the 4th and 6th instar larvals were first induced, and then inhibited too. The highest activities of POD in the 4th and 6th instar larvals occurred in 24 h,and were 1. 603 and 1. 805 times of CK in the same instar. The lowest activities of POD in the 4 th and 6th instar larvals occurred in 48 h after being treated with methoxyfenozide, and they were 0. 858 and 0. 608 times of CK in the same instar, these differences were significant (P <0. 01) . POD activities of 2nd instar larvaes were remarkably inhibited by methoxyfenozide treatment,and the lowest activities of POD arose in 24 h,with 0. 541 times of CK in the same instar, the difference was significant (P <0. 01 ). The activities of chitinase activities showed different with different instar after treatment with methoxyfenozide, and the chitinase activities in the 2nd instar larvaes were first induced, and then inhibited. But the chitinase activities in the 4th instar larvae and 6th instar larvae were inhibited obviously. Therefore, it was shown that methoxyfenozide disturbed the insect regular metabolism in the larvaes, by which the chemical could efficiently poison L. Dispar.