Relative Activity of a Tobacco Hybrid Expressing High Levels of a Tobacco Anionic Peroxidase and Maize Ribosome-Inactivating Protein against Helicoverpa zea and Lasioderma serricorne
Tobacco (Nicotiana tabacum) plants grown from seed obtained by crossing a tobacco line thatexpressed an activated maize ribosome-inactivating protein (RIP) with a line that overexpressedtobacco anionic peroxidase were tested for their effects on corn earworm Helicoverpa zea and cigarettebeetle Lasioderma serricorne larvae as compared to the wild-type plant cross. Significant feedingreductions were noted for transgenic plants expressing both resistance proteins as compared to wild-type plants for both H. zea and L. serricorne. Significant increases in mortality were also noted forthose insects fed on the transgenic cross as compared to wild-type plants in some cases. Levels ofboth peroxidase and maize RIP were significantly higher in transgenic as compared to wild-typeplants (which did not produce maize RIP). The degree of feeding was significantly negatively correlatedwith the level of RIP or peroxidase individually.Keywords: Helicoverpa; Lasioderma; peroxidase; ribosome-inactivating protein; insect resistance;transgenic