Data from: Cultivation shapes genetic novelty in a globally important invader

Acacia saligna is a species complex that has become invasive in a number of countries worldwide where it has caused substantial environmental and economic impacts. Understanding genetic and other factors contributing to its success may allow managers to limit future invasions of closely related species. We used three molecular markers to compare the introduced range (South Africa) to the native range (Western Australia). Nuclear markers showed that invasive populations are divergent from native populations and most closely related to a cultivated population in Western Australia. We also found incongruence between nuclear and chloroplast data that, together with the long history of cultivation of the species, suggest that introgressive hybridization (coupled with chloroplast capture) may have occurred within A. saligna. While we could not definitively prove introgression, the genetic distance between cultivated and native A. saligna populations was comparable to known interspecific divergences among other Acacia species. Therefore, cultivation, multiple large-scale introductions and possibly introgressive hybridization have rapidly given rise to the divergent genetic entity present in South Africa. This may explain the known global variation in invasiveness and inaccuracy of native bioclimatic models in predicting potential distributions.银叶金合欢（Acacia saligna）是一个物种复合群（species complex），已在全球多个国家沦为入侵物种，造成了显著的生态与经济影响。解析其成功入侵的遗传及其他驱动因素，可为管理者防控近缘物种的后续入侵提供理论支撑。本研究选用三种分子标记（molecular markers），对该物种的入侵分布区（南非）与原生分布区（西澳大利亚）开展对比分析。核基因标记（nuclear markers）结果表明，入侵种群与原生种群存在遗传分化，且与西澳大利亚地区的一个栽培种群亲缘关系最近。我们同时发现核基因与叶绿体（chloroplast）数据之间存在不一致性，结合该物种悠久的栽培历史，推测银叶金合欢种内可能发生了渐渗杂交（introgressive hybridization），伴随叶绿体捕获（chloroplast capture）。尽管本研究无法确凿证实渐渗事件的发生，但栽培种群与原生银叶金合欢种群之间的遗传距离（genetic distance），与其他金合欢属物种间已知的种间遗传分化程度相当。因此，栽培活动、多次大规模引种以及可能存在的渐渗杂交，共同快速塑造了南非地区现存的具有遗传分化的种群类群。该结果或可解释学界观测到的全球范围内银叶金合欢入侵性差异，以及生物气候模型（bioclimatic models）在基于原生分布区预测其潜在分布时出现的偏差。