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Cypermethrin Effects on Detoxification Enzymes in Active and Hibernating Wolf Spiders (Pardosa amentata)
S. A. Nielsen, S. Toft and J. Clausen
Vol. 9, No. 2 (May, 1999), pp. 463-468
Stable URL: http://www.jstor.org/stable/2641135
Page Count: 6
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Spiders are among the most important predators of insect pests in all types of agricultural situations. The activity of three systems of detoxification enzymes, glutathione transferase (GST) and two glutathione peroxidases (GSH-Px), was measured in cypermethrin-treated wolf spiders (Pardosa amentata) collected at three different times in relation to hibernation. On each occasion separate groups of spiders had been treated by topical application with four doses of cypermethrin and compared to controls. The results indicate different responses of these enzymes with respect to life cycle variation and inducibility by cypermethrin. GST responded only slightly to cypermethrin, activity being reduced at high doses. It showed a remarkable seasonal variation, with winter season activity reduced to half that of active periods. GSH-Px(H2O2) and GSH-Px(TBH) had very low basal activity in autumn, but higher activity could be induced by cypermethrin. In winter, basal levels of these systems were high and cypermethrin reduced their activity. In spring GSH-Px(H2O2) returned to the autumn pattern. GSH-Px(TBH) maintained a high basal level that could be further induced. Our findings indicate that during hibernation spiders have several detoxification systems that are active, while during active phases they rely more on inducibility.
Ecological Applications © 1999 Wiley