Storer Nicholas P, Peck Steven L, Gould Fred, Van Duyn John W, Kennedy George G
Department of Entomology, College of Agriculture and Life Sciences, North Carolina State University, Raleigh, NC 27695, USA.
J Econ Entomol. 2003 Feb;96(1):173-87. doi: 10.1093/jee/96.1.173.
The sensitivities of a model simulating the evolution of resistance in Helicoverpa zea to Bt toxins in transgenic crops were investigated by examining effects of each of the model parameters on the frequency of resistance alleles after 8 yr. The functional dominance of resistance alleles and the initial frequency of those alleles had a major impact on resistance evolution. The survival of susceptible insects on the transgenic crops and the population dynamics of the insect, driven by winter survival and reproductive rates, were also important. In addition, agricultural practices including the proportion of the acreage planted to corn, and the larval threshold for spraying cotton fields affected the R-allele frequency. Many of these important parameters are inherently variable or cannot be measured with accuracy, so model output cannot be interpreted as being a forecast. However, this analysis is useful in focusing empirical research on those aspects of the insects' life system that have the largest effects on resistance development, and indicates ways in which to improve products and agricultural practices to increase the expected time to resistance. The model can thus be used as a scientific basis for devising a robust resistance management strategy for Bt crops.
通过研究模型的每个参数对8年后抗性等位基因频率的影响，对一个模拟棉铃虫对转基因作物中Bt毒素抗性进化的模型的敏感性进行了调查。抗性等位基因的功能显性和这些等位基因的初始频率对抗性进化有重大影响。敏感昆虫在转基因作物上的存活以及由冬季存活率和繁殖率驱动的昆虫种群动态也很重要。此外，包括玉米种植面积比例以及棉花田喷洒农药的幼虫阈值在内的农业实践也会影响抗性等位基因频率。这些重要参数中的许多本质上是可变的，或者无法准确测量，因此模型输出不能被解释为一种预测。然而，这种分析有助于将实证研究聚焦于昆虫生命系统中对抗性发展影响最大的那些方面，并指出改进产品和农业实践以延长预期抗性出现时间的方法。因此，该模型可作为制定稳健的Bt作物抗性管理策略的科学依据。
