Although host plant resistance has long been an important insect management tactic, its wide-spread use has been constrained by the limited availability of elite cultivars possessing high levels of resistance to key pest species. The application of recombinant DNA technology to genetically engineer insect-resistant crop plants has provided a way to eliminate this constraint and make host plant resistance a prominent component of integrated pest management (IPM) in major cropping systems world-wide. It is within the framework of IPM, rather than as a stand-alone insect control measure, that insect-resistant GM crops have the greatest potential to contribute to the establishment of sustainable crop protection systems. This chapter reviews the defining elements of IPM and examines the attributes of insect-resistant GM crops as IPM tools. Insect-resistant GM crops available to date, like their counterparts developed through conventional plant breeding, are proving to be safe, effective and easy to use insect suppression tools that are compatible with other IPM tactics, including cultural and chemical controls and the conservation of natural enemies as important agents of biological control. Because of their high level of efficacy against the key pest species that they target, GM Bt cotton and Bt maize varieties expressing cry genes derived from Bacillus thuringiensis (Bt) have been widely adopted and have led to significant reductions in insecticide use. Experience in Bt cotton has revealed the potential for reductions in insecticide use to be accompanied by the emergence of secondary pests and the need to adjust the pest management systems to address these “new” pests. Emphasis on the importance of resistance management to mitigate selection for pest adaptation to Bt crops has elevated the role of resistance management to a position of fundamental importance in the implementation of IPM.

Integration of Insect-Resistant Genetically Modified Crops within IPM Programs

This paper provides recommendations on experimental design for early-tier laboratory studies used in risk assessments to evaluate potential adverse impacts of arthropod-resistant genetically engineered (GE) plants on non-target arthropods (NTAs). While we rely heavily on the currently used proteins from Bacillus thuringiensis (Bt) in this discussion, the concepts apply to other arthropod-active proteins. A risk may exist if the newly acquired trait of the GE plant has adverse effects on NTAs when they are exposed to the arthropod-active protein. Typically, the risk assessment follows a tiered approach that starts with laboratory studies under worst-case exposure conditions; such studies have a high ability to detect adverse effects on non-target species. Clear guidance on how such data are produced in laboratory studies assists the product developers and risk assessors. The studies should be reproducible and test clearly defined risk hypotheses. These properties contribute to the robustness of, and confidence in, environmental risk assessments for GE plants. Data from NTA studies, collected during the analysis phase of an environmental risk assessment, are critical to the outcome of the assessment and ultimately the decision taken by regulatory authorities on the release of a GE plant. Confidence in the results of early-tier laboratory studies is a precondition for the acceptance of data across regulatory jurisdictions and should encourage agencies to share useful information and thus avoid redundant testing.

https://link.springer.com/content/pdf/10.1007%2Fs11248-010-9446-x.pdf

Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants

This paper provides recommendations on experimental design for early-tier laboratory studies used in risk assessments to evaluate potential adverse impacts of arthropod-resistant genetically engineered (GE) plants on non-target arthropods (NTAs). While we rely heavily on the currently used proteins from Bacillus thuringiensis (Bt) in this discussion, the concepts apply to other arthropod-active proteins. A risk may exist if the newly acquired trait of the GE plant has adverse effects on NTAs when they are exposed to the arthropod-active protein. Typically, the risk assessment follows a tiered approach that starts with laboratory studies under worst-case expo- sure conditions; such studies have a high ability to detect adverse effects on non-target species. Clear guidance on how such data are produced in labora- tory studies assists the product developers and risk assessors. The studies should be reproducible and test clearly defined risk hypotheses. These properties

Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants Jorg RomeisRichard L. HellmichMarco P. CandolfiKeri Carstens • Adinda De SchrijverAngharad M. R. GatehouseRod A. Herman • Joseph E. HuesingMorven A. McLeanAlan RaybouldAnthony M. Shelton •

Problem formulation is the first step in environmental risk assessment (ERA) where policy goals, scope, assessment endpoints, and methodology are distilled to an explicitly stated problem and approach for analysis. The consistency and utility of ERAs for genetically modified (GM) plants can be improved through rigorous problem formulation (PF), producing an analysis plan that describes relevant exposure scenarios and the potential consequences of these scenarios. A properly executed PF assures the relevance of ERA outcomes for decision-making. Adopting a harmonized approach to problem formulation should bring about greater uniformity in the ERA process for GM plants among regulatory regimes globally. This paper is the product of an international expert group convened by the International Life Sciences Institute (ILSI) Research Foundation.

/pdf/problem-formulation-in-the-environmental-risk-assessment-for-2yqcreebc0.pdf

Problem formulation in the environmental risk assessment for genetically modified plants.

The main environmental concerns about genetically modified (GM) crops are the potential weediness or invasiveness in the crop itself or in its wild or weedy relatives as a result of transgene movement. Here we briefly review evidence for pollen- and seed-mediated gene flow from GM crops to non-GM or other GM crops and to wild relatives. The report focuses on the effect of abiotic and biotic stress-tolerance traits on plant fitness and their potential to increase weedy or invasive tendencies. An evaluation of weediness and invasive traits that contribute to the success of agricultural weeds and invasive plants was of limited value in predicting the effect of biotic and abiotic stress-tolerance GM traits, suggesting context-specific evaluation rather than generalizations. Fitness data on herbicide, insect, and disease resistance, as well as cold-, drought-, and salinity-tolerance traits, are reviewed. We describe useful ecological models predicting the effects of gene flow and altered fitness in GM crops and wild/weedy relatives, as well as suitable mitigation measures. A better understanding of factors controlling population size, dynamics, and range limits in weedy volunteer GM crop and related host or target weed populations is necessary before the effect of biotic and abiotic stress-tolerance GM traits can be fully assessed.

Gene Flow, Invasiveness, and Ecological Impact of Genetically Modified Crops

Representatives of the developers of modern agricultural biotechnology are proposing a tiered approach for conducting non-target organism risk assessment for genetically modified (GM) plants in Europe. The approach was developed by the Technical Advisory Group of the EuropaBio Plant Biotechnology Unit (http://www.europabio.org/TAG.htm) and complements other international activities to harmonize risk assessment. In the European Union (EU), the principles and methods to be followed in an environmental risk assessment for the placing on the market of GM plants are laid out in Annex II of Directive 2001/18/EC on the deliberate release into the environment of GMOs, Commission Decision 2002/623/EC and Regulation (EC) No. 1829/2003. Additional information is provided in the European Food Safety Authority guidance document of 2004. However, risk assessment for effects to non-target organisms could benefit from further clarification and remains the subject of much discussion in Europe. The industry-wide approach developed by EuropaBio is based on the fundamental steps of risk evaluation, namely hazard and exposure assessment. It follows a structured scheme including assessment planning, product characterization and assessment of hazard/exposure (Tier 0), single high dose and dose response testing (Tier 1), refined hazard characterization and exposure assessment (Tier 2) and further refined risk assessment experiments (Tier 3). An additional tier (Tier 4) was included to reflect the fact that post-market activities such as monitoring are required under Directive 2001/18/EC. The approach is compatible with conditions of commercial release in the EU and around the world.

https://www.ebr-journal.org/articles/ebr/pdf/2006/02/ebr0606.pdf

Erik Jacobs

Papers

A tiered system for assessing the risk of genetically modified plants to non-target organisms.