Transgenic-Bt potato plant resistance to the colorado potato beetle affect the aphid parasitoid Aphidius nigripes

Using the biotechnological plant resistance for herbivore control with less reliance on chemicals in integrated pest management (IPM) programs critically depends on predictable interactions with no-target organisms of various trophic levels. Plant resistance to insect pests based on recombinant Bacillus thuringiensis could interfere with natural enemies of non target pests. Performance of the potato aphid parasitoid Aphidius nigripes was studied on the 'Superior-BT line transgenic for the CryllIA toxin of B. thuringiensis, resistance to the Colorado potato beetle; and none transformed 'Superior' line which served as control. Parasitoid survival was significantly lower on the 'Superior-BT' line compared to control. Adult females were largest on 'Superior' and smallest on BT potatoes. This difference was reflected on parasitoid fecundity, which was lowest on 'Superior-BT', and highest on Superior. The results indicate that factor of potato resistance to the Colorado potato beetle affected the fitness of a parasitold of the aphid Macrosiphum euphorbiae, a secondary pest of potato. The effects on the parasitoid were complex but were generally interpretable in terms of host aphid quality variation among potato lines used as food by the aphids during parasitoid development.