Bt crops and food security in developing countries: realised benefits, sustainable use and lowering barriers to adoption

摘要

Transgenic crops producing insecticidal proteins from the bacterium Bacillus thuringiensis (Bt crops) have been cultivated commercially for over 15 years. Worldwide, Bt crops have provided effective control of target pests with fewer applications of insecticide, have increased yield and profitability for farmers, and have reduced risk to the environment and human health compared with non-Bt crops. Sustainable use of Bt crops requires risk management to limit the evolution of pest resistance and adverse effects of the Bt proteins to non-target organisms. Risks are managed by national regulatory authorities; however, the establishment of functional regulatory systems with the necessary scientific capacity is problematic in many developing countries, which hinders the wider deployment of Bt and other transgenic insect-resistant crops. Timely introduction of these crops may also be obstructed by inefficient implementation of international regulatory regimes, such as the Cartagena Protocol on Biosafety (CPB). Regulatory costs limit the number of insect-resistant crops that may be developed, and delay in the introduction of such crops may result in large opportunity costs. Implementing effective risk management while limiting these costs requires clear policy that defines the benefits and harms of cultivating transgenic crops and how those benefits and harms should be weighed in decision-making. Policy should lead to the development of regulatory frameworks that minimise the number of new data requirements and maximise the value of existing studies for risk assessment; costs will thereby be reduced, increasing the prospects for Bt crops, and transgenic insect-resistant crops generally, to improve food security in developing countries.