Plant invasions are rarely homogenous. Processes such as selection, drift, gene flow, and founding events can rapidly shape the genetic diversity and spatial population structure of an invasion. We investigated the diversity, origins and population structure of Verbascum thapsus (common mullein), an introduced plant in North America. Despite this species being facultatively outcrossing, we found the invasion dominated by a single genotype (61% of plants were identical amplified fragment length polymorphism [AFLP] genotypes in the western USA). Fifty percent of the invasion populations were monotypic, and we found 32 genotypes overall in the 431 plants sampled from the invasion. In contrast, populations were much more diverse in the native Eurasian range, with 394 genotypes found in 479 plants. Further, we found an exact genetic match between the common genotype 1 in the USA and plants from Belgium and Germany. The identification of the most common and diverse invasive genotypes of common mullein allows their use in tests of management tools and further studies of mechanisms of this invasion.

植物入侵很少是同质的。选择，漂移，基因流动和成立事件等过程可以迅速塑造入侵的遗传多样性和空间种群结构。我们调查了触须草的多样性，起源和种群结构（普通毛勒菌素），是北美的一种引进植物。尽管该物种在兼性上是异交的，但我们发现入侵是由单一基因型主导的（61％的植物是美国西部相同的扩增片段长度多态性[AFLP]基因型）。50％的入侵种群是单型的，我们在从入侵样本中抽取的431株植物中发现了32种基因型。相比之下，欧亚大陆范围内的种群更加多样化，在479种植物中发现了394个基因型。此外，我们发现美国常见基因型1与比利时和德国的植物之间存在精确的遗传匹配。鉴定普通毛蛋白的最常见和最广泛的侵入性基因型可将其用于管理工具的测试和这种侵入机制的进一步研究中。