Abstract
An important concern with the use of genetically modified (GM) plants expressing Bacillus thuringiensis (Bt) insecticidal toxins is the deleterious effect on non–target organisms. The predatory stink bug Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae) is used in biological control programs and may be exposed to Bt toxins. This study evaluated the indirect effects of different Cry proteins on P. nigrispinus with the prey Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae), fed on simple or pyramided Bt maize genotypes. The experiment was carried out in a completely randomized design with three treatments: i) Isohybrid (not Bt), ii) Herculex® (transgenic maize encoding Cry1F protein) and iii) PowerCore® (pyramidal transgenic maize encoding the Cry1F, Cry1A.105, and Cry2Ab2 proteins), which were used to feed S. frugiperda for 48 h. The caterpillars were used as prey by P. nigrispinus females. We evaluated the presence of Cry proteins, consumed prey biomass (predation), oviposition period, number of postures, number of eggs, number of eggs per posture, number of nymphs, egg viability, embryonic period, female longevity and development, and survival rates of immature. The results show that different Cry proteins move through the food chain of P. nigrispinus and provide evidence that the ingestion of three different proteins does not lead to unexpected synergistic effects. However, Cry toxins promoted histopathological changes in midgut cells of P. nigrispinus.
Highlights
Modified (GM) crops that contain genes introduced by genetic engineering to control insects express pesticidal proteins (Cry) from the bacterium Bacillus thuringiensis (Bt) that may have insecticidal action on insects of the orders Lepidoptera, Coleoptera, Hymenoptera, and Diptera (Abbas, 2018)
This study evaluated the flow of different Cry proteins in P. nigrispinus fed on S. frugiperda previously fed on simple or pyramided Bt maize genotypes, as well as the developmental, predatory, and reproductive ability of the predator
The results of QuickStixTM strips with Herculex® and PowerCore® were positive for maize leaves, S. frugiperda fed on Bt maize, and samples with the predator P. nigrispinus that predated S. frugiperda
Summary
Modified (GM) crops that contain genes introduced by genetic engineering to control insects express pesticidal proteins (Cry) from the bacterium Bacillus thuringiensis (Bt) that may have insecticidal action on insects of the orders Lepidoptera, Coleoptera, Hymenoptera, and Diptera (Abbas, 2018). Because of their high control efficacy and ease use, Bt crops have increased rapidly (Huang, 2020). Different Cry proteins in stacked or pyramidal Bt plants may interact synergistically and lead to unexpected effects on non–target species (Hilbeck and Otto, 2015)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
