Ecological compatibility of GM crops and biological control

Abstract

Insect-resistant and herbicide-tolerant genetically modified (GM) crops pervade many modern cropping systems (especially field-cropping systems), and present challenges and opportunities for developing biologically based pest-management programs. Interactions between biological control agents (insect predators, parasitoids, and pathogens) and GM crops exceed simple toxicological relationships, a priority for assessing risk of GM crops to non-target species. To determine the compatibility of biological control and insect-resistant and herbicide-tolerant GM crop traits within integrated pest-management programs, this synthesis prioritizes understanding the bi-trophic and prey/host-mediated ecological pathways through which natural enemies interact within cropland communities, and how GM crops alter the agroecosystems in which natural enemies live. Insect-resistant crops can affect the quantity and quality of non-prey foods for natural enemies, as well as the availability and quality of both target and non-target pests that serve as prey/hosts. When they are used to locally eradicate weeds, herbicide-tolerant crops alter the agricultural landscape by reducing or changing the remaining vegetational diversity. This vegetational diversity is fundamental to biological control when it serves as a source of habitat and nutritional resources. Some inherent qualities of both biological control and GM crops provide opportunities to improve upon sustainable IPM systems. For example, biological control agents may delay the evolution of pest resistance to GM crops, and suppress outbreaks of secondary pests not targeted by GM plants, while herbicide-tolerant crops facilitate within-field management of vegetational diversity that can enhance the efficacy of biological control agents. By examining the ecological compatibility of biological control and GM crops, and employing them within an IPM framework, the sustainability and profitability of farming may be improved. RightsWorks produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted. b s t r a c tInsect-resistant and herbicide-tolerant genetically modified (GM) crops pervade many modern cropping systems (especially field-cropping systems), and present challenges and opportunities for developing biologically based pest-management programs. Interactions between biological control agents (insect predators, parasitoids, and pathogens) and GM crops exceed simple toxicological relationships, a priority for assessing risk of GM crops to non-target species. To determine the compatibility of biological control and insect-resistant and herbicide-tolerant GM crop traits within integrated pest-management programs, this synthesis prioritizes understanding the bi-trophic and prey/host-mediated ecological pathways through which natural enemies interact within cropland communities, and how GM crops alter the agroecosystems in which natural enemies live. Insect-resistant crops can...

Changes in Arthropod Fauna From Weed Management Practices in Genetically Modified Herbicide-Tolerant Maize

“…Arthropod-weed interactions have been dealt with in the review by Norris and Kogan (2000), the analysis of the compatibility of GMHT crops and biological control by Lundgren et al (2009) and the study of the influence of weed control and crop management practices on invertebrates by Smith et al (2008). However, little generalization has been provided in this field by plant and insect ecologists.…”

The effect of Cry1AB insecticidal protein on the incidence of entomopathogenic fungi infecting aphids on Bt maize

“…Some synergistic interactions between Cry toxin and entomopathogen fungi have also been found (Wraight, Ramos, 2005). Taken this latter knowledge into account, Lundgren et al (2009) pointed out that hypothesis about positive or negative effects of Bt plants on fungi should be validated by looking on specific entomopathogen species or community.…”

“…Because of the reflections above, and according to the results of our trials, we assume no effect of Bt maize on entomopathogens recorded on cereal aphids colonizing maize in the GM ecosystem. In the review form Lundgren et al (2009) stated that there is evidence for both positive and negative indirect effects of Cry toxin on entomopathogens. In the literature some effects of Bt toxins on fungi in soil were better examined.…”

Impactos do controle de plantas daninhas e da aplicação de herbicidas em inimigos naturais

“…Lower plant diversity can affect the abundance of natural enemies and harm the natural pest control in agricultural or forestry crops (Hawes et al, 2009;Lundgren, 2009). Therefore, practices aiming at maintaining plant diversity to a level that will not threaten the development of agricultural crops must be properly studied.…”