Effects of artificial diet containing GNA and GNA-expressing potatoes on the development of the aphid parasitoid Aphidius ervi Haliday (Hymenoptera :Aphidiidae)

Aphid parasitoids are important biological control agents. The possibility arises that whilst foraging on insect-resistant transgenic plants, they are themselves at risk from direct and indirect effects of the expression of a transgene used to control the pest species. A liquid artificial diet was s uccessfully used to deliver the snowdrop lectin (Galanthus nivalis agglutin in; GNA) to the peach-potato aphid, Myzus persicae. Bioassays utilising art ificial diet incorporating GNA, and excised leaves of the GNA-expressing tr ansgenic potato line, GNA2#28, were performed to assess the potential effec ts of GNA on the development of the aphid parasitoid Aphidius ervi. The res ults indicate that GNA delivered via artificial diet to the aphids can be t ransferred through the trophic levels and has a dose-dependent effect on pa rasitoid development. Parasitoid larvae excreted most of the ingested GNA i n the meconium but some of it was detected in the pupae. Although A. ervi d evelopment was not affected when developing within hosts feeding on transge nic potato leaves, this probably reflected sub-optimal expression of the to xin in the transgenic potato line used (C) 2001 Elsevier Science Ltd. All r ights reserved.