DISSERTATION RESEARCH: Evolutionary Genetics of Novel Herbicide Tolerance in the Common Morning Glory

采用化学方法根除害虫物种加强了农业生产，但代价是抗药性生物的快速进化。我们对除草剂除草剂农达的新耐性进化的观察。在普通的牵牛花中，紫花野芥菜提供了一个人类中介进化的极好例子。我们有来自温室初步研究的证据表明，紫花菜母系对除草剂的耐受性存在遗传变异。我们将通过研究除草剂耐受性的遗传控制和对其进化的潜在限制来进一步研究这一性状的进化。这些实验将通过进行温室杂交和随后的后代分析来检验耐受性是如何遗传的。在田间没有除草剂的情况下，通过比较耐除草剂个体和敏感个体的相对适合度来研究限制耐受性进化的可能性。这项研究对美国农业的更广泛影响是显而易见的。由于农达的使用正在显著增加，因此完成对其使用的演变分析至关重要。了解对这种除草剂耐受性的遗传基础和适应成本将具有广泛的重要性。

The introduction of chemical means of eradicating pest species intensified agricultural production, but at the cost of rapid evolution of resistant organisms. Our observation of the evolution of novel tolerance to the herbicide RoundUp. In the common morning glory, Ipomoea purpurea, provides an excellent example of human-mediated evolution. We have evidence from a preliminary greenhouse study that there is genetic variation among maternal lines of Ipomoea purpurea for tolerance to RoundUp. We will further investigate the evolution of this trait by studying the genetic control of herbicide tolerance and the potential constraints on its evolution. The experiments will examine how tolerance is inherited by performing greenhouse crosses and subsequent progeny analyses. The potential for constraints on the evolution of tolerance will be investigated by comparing relative fitness of herbicide tolerant and susceptible individuals in the absence of herbicide in the field. The broader impacts of this study are manifest to U.S. agriculture. Since use of RoundUp is increasing markedly, it is critical that evolutionary analyses of its use be completed. An understanding of the genetic basis and fitness costs of tolerance to this herbicide will be of broad importance.