Data from: Evolutionary significance of the invasion of introduced populations into the native range of Meconopsis cambrica

The long history of the deliberate or accidental, human-mediated dispersal of flowering plants has led to the introduction of foreign genotypes of many species into areas of Europe hitherto occupied by potentially distinct native populations. Studies of the genetic and evolutionary consequences of such changes are handicapped by the difficulty of identifying the surviving native populations of many species in the absence of clear morphological differences. We investigated the relationship between putative native and introduced populations of the herbaceous perennial Meconopsis cambrica (Papaveraceae), as the isolated native populations of this species can be identified by historical and ecological evidence. In Britain the species is scarce and declining as a native but has become increasingly frequent in recent decades as a garden escape. Native populations from Spain and France were compared to native and introduced British populations using ITS and cpDNA sequences and AFLPs. Ten of the twelve British populations could be unambiguously assigned to native or introduced groups using cpDNA and AFLPs. The introduced plants appear to originate from the central and eastern Pyrenees rather than from native British sites. Two populations (including one previously considered native) cannot be classified unambiguously. There is unequivocal evidence for unidirectional gene-flow from native plants into two of the introduced populations and possible evidence for hybridization in three other sites (two native). The absence of biological barriers to hybridization suggests that the native and introduced gene pools of M. cambrica in Britain might eventually merge.

长期以来，人类有意或无意介导的显花植物传播历史，已导致诸多物种的外来基因型被引入至欧洲此前由潜在独特本土种群占据的区域。由于缺乏清晰的形态学差异，难以识别多数物种的现存本土种群，这一困境制约了对这类变化所带来的遗传与进化后果的研究。我们以多年生草本植物威尔士绿绒蒿（Meconopsis cambrica，罂粟科）为研究对象，探究其推定本土种群与引入种群之间的关联——该物种的孤立本土种群可通过历史与生态学证据加以识别。在英国，该物种作为本土种群数量稀少且呈下降趋势，但近几十年来作为园艺逸生种愈发常见。研究人员采用内转录间隔区（Internal Transcribed Spacer，ITS）、叶绿体DNA（chloroplast DNA，cpDNA）序列以及扩增片段长度多态性（Amplified Fragment Length Polymorphisms，AFLPs）技术，将来自西班牙与法国的本土种群，与英国的本土及引入种群进行对比分析。借助cpDNA与AFLPs数据，12个英国种群中的10个可被明确归类为本土种群或引入种群。引入种群的起源地似乎为比利牛斯山脉中部与东部，而非英国本土种群分布区。另有2个种群（包含1个此前被认定为本土种群的类群）无法被明确归类。有明确证据表明，存在从本土种群向2个引入种群的单向基因流；另有3个位点（其中2个为本土种群）存在杂交的潜在证据。杂交不存在生物学障碍，这意味着英国境内威尔士绿绒蒿的本土基因库与引入基因库最终可能发生融合。