Several strategies involving refuge have been proposed for delaying insect resistance to Bt crops. The report was focused on the unstructured ‘natural’ refuges that contain plants naturally presented as part of the cropping system in the form of non-Bt plants that differ from Bt plant species, or wild host plants of the target pests. The cases of natural refuges applied in different countries were analyzed, and the factors that favor their success are discussed. The results indicate that the effectiveness of a natural refuge strategy depends on the biological characteristics of the target pest, the spatial and temporal distribution and abundance of the host plants in the agricultural system and the quality of the host plants for the pest species.

已经提出了几种涉及避难的策略来延迟昆虫对Bt作物的抗性。该报告的重点是含有自然而然地出现在非形式的种植系统的一部分植物的非结构化的“自然”庇护Bt基因，从不同的植物转Bt基因植物品种，或靶标害虫的野生寄主植物。分析了在不同国家使用的自然避难所案例，并讨论了其成功的因素。结果表明，自然保护区策略的有效性取决于目标害虫的生物学特性，宿主植物在农业系统中的时空分布和丰度以及害虫物种的宿主植物质量。