Impact Assessment of Genetically Engineered Trees: An Overview on Risk Assessment and Management

Although contentious, transformative biotechnologies such as genetic engineering, and more recently genome editing, are often heralded as the panacea for a wide range of global challenges facing agriculture and forestry. Genetically engineered or genome-edited (genetically modified; GM) trees are touted to provide several benefits such as increased yield, faster growth, shorter rotations, improved resistance to pests and diseases, reduced need for pesticides and fertilisers, and enhanced adaptability to changing environmental conditions. While these technologies have advanced significantly in recent years, there are a plethora of risks and concerns associated with the release of GM plants in natural environments, namely, erosion of genetic diversity, imbalances in natural ecosystem processes, the risk of spread of transgenes leading to herbicide-resistant plants (superweeds) and antibiotic-resistant microbes (superbugs), in addition to several other issues. Thus, release of GM trees into the natural environment raises several concerns, and an effective impact assessment must include the short-term and long-term impact on environment, ecology, ecosystem functioning; socio-economic aspects such as effects on ecosystem services, local communities; and impact on human, animal, and forest health. Moreover, public participation, transparency, and stringent regulatory oversight have to be ensured so that any release decision is based on a comprehensive and unbiased impact assessment. This will guarantee that the benefits of GM trees are realised while minimising risks to people and the environment. Although contemporary regulatory policies for GM agricultural crops are well-established, the introduction of GM trees into ecologically sensitive areas poses more complex risks and, hence, requires enhanced precaution and rigorous regulatory oversight. This chapter discusses the prospective benefits and risks associated with genetically engineered/edited trees for forest plantations, their potential ecological and socio-economic impact, and the methodologies and regulatory policies in place for their risk/impact assessment and management.