经基因工程改造的可表达来自苏云金芽孢杆菌（Bacillus thuringiensis）蛋白的农作物常常被称作Bt作物，这些作物可增加农作物的产量并同时降低虫害以及对其它杀虫剂的需求。 但是，据5月14日的《科学》杂志报道说，在中国北方对作物所做的一项为期10年的研究披露，Bt棉花的使用使得该地区害虫种群的平衡发生转变：蝽科虫子的种群过去在该地区仅是一种次要的害虫，但最近却有了急剧的增加。 Yanhui Lu及其同僚将其在野外工作的数据进行了编撰，并首次报告了这一栽种Bt棉花的非计划性后果的详尽调查。 这些研究人员提出，蝽科虫子种群在最近的爆炸式增长是因为在这一地区引进了这些基因改良的作物之后，传统农药的使用有所减少之故。 由于蝽科虫子会吃范围广泛的植物，Lu及其同僚说，这种害虫现在第一次成为对其它作物（其中包括葡萄、苹果、桃子和梨）的一种威胁。 这些发现证明，针对某一特别害虫的害虫控制政策的改变会导致其它非目标性害虫的扩散。他们强调了在贯彻大面积的病虫害治理策略之前分析这些可能性的重要性。

参阅文献：Published Online May 13, 2010,Science DOI: 10.1126/science.1187881

Mirid Bug Outbreaks in Multiple Crops Correlated with Wide-Scale Adoption of Bt Cotton in China

Long-term ecological effects of transgenic Bacillus thuringiensis (Bt) crops on non-target pests have received limited attention, more so in diverse smallholder-based cropping systems of the developing world. Field trials conducted over 10 years in northern China show that mirid bugs (Heteroptera: Miridae) have progressively increased population levels and acquired pest status in cotton and multiple other crops, in association with a regional increase in Bt cotton adoption. More specifically, our analyses show that Bt cotton has become a source of mirid bugs and that their population increases are related to drops in insecticide use in this crop. Hence, alterations of pest management regimes in Bt cotton could be responsible for the appearance and subsequent spread of non-target pests at an agro-landscape level.