Home banner
A-Z Index

Quick way to the find the information that you need...

More button
Register with FRAME

Although you do not need to register, any information you provide will be confidential and used only by FRAME to improve the website

Register button
Account Login
Forgot password?

The Journal


Alternatives to Laboratory Animals - ATLA

Download latest issue button Download back issues button Subscribe to ATLA
Contact Us

Tel icon

Tel: +44 (0)115 9584740

Tel icon

Fax: +44 (0)115 9503570

Make an Enquiry

Activities of Glutathione S-Transferase and Glutathione Peroxidases Related to Diet Quality in an Aphid Predator, the Seven-spot Ladybird, Coccinella septempunctata L. (Coleoptera: Coccinellidae)

Søren Achim Nielsen, Mikael S. Hauge, Frederik H. Nielsen and Søren Toft2

Larvae of Coccinella septempunctata were reared on three aphid diets, consisting of pure Rhopalosiphum padi, pure Metopolophium dirhodum, and an equal mix of these aphid species. In the pupal stage, the activities of three detoxifying enzyme systems — glutathione Stransferase (GST) with 1-chloro-2,4-dinitrobenzene as substrate, glutathione peroxidase with hydrogen peroxide as substrate (GSH-Px[H2O2]), and glutathione peroxidase with tert-butyl hydroperoxide as substrate (GSH-Px[TBH]) — were assayed. Growth rate, measured as the total protein content of the pupae, was significantly higher in the mixed-diet group than in the R. padi group, whereas that of the M. dirhodum group was intermediate. GST showed lower activity in larvae on a pure R. padi diet and a mixed aphid diet than on a pure M. dirhodum diet, whereas the variation in GSH-Px[TBH] was independent of diet. GSH-Px(H2O2) showed a significantly higher activity in the R. padi group than in the M. dirhodum group, whereas that of the mixed-diet group was intermediate. Thus, feeding on the low-quality aphid, R. padi, inhibited GST and activated GSH-Px(H2O2). The induction of GSH-Px[H2O2] indicated elevated oxidative stress. This may have been caused by toxic compounds in the R. padi.