Department of Botany, Charles University, Prague, Czech Republic.
Czech Academy of Sciences, Institute of Botany, Průhonice, Czech Republic.
Plant J. 2023 Nov;116(3):773-785. doi: 10.1111/tpj.16408. Epub 2023 Aug 3.
Hybridization is a widespread phenomenon in the evolution of plants and exploring its role is crucial to understanding diversification processes of many taxonomic groups. Recently, more attention is focused on the role of ancient hybridization that has repeatedly been shown as triggers of evolutionary radiation, although in some cases, it can prevent further diversification. The causes, frequency, and consequences of ancient hybridization remain to be explored. Here, we present an account of several events of ancient hybridization in turmeric, the economically important plant genus Curcuma (Zingiberaceae), which harbors about 130 known species. We analyzed 1094 targeted low-copy genes and plastomes obtained by next-generation sequencing of 37 species of Curcuma, representing the known genetic diversity and spanning the geographical distribution of the genus. Using phylogenetic network analysis, we show that the entire genus Curcuma as well as its most speciose lineage arose via introgression from the genus Pyrgophyllum and one of the extinct lineages, respectively. We also document a single event of ancient hybridization, with C. vamana as a product, that represents an evolutionary dead end. We further discuss distinct circumstances of those hybridization events that deal mainly with (in)congruence in chromosome counts of the parental lineages.
杂交是植物进化中的一种广泛现象，探索其作用对于理解许多分类群的多样化过程至关重要。最近，人们越来越关注古老杂交的作用，它已被多次证明是进化辐射的触发因素，尽管在某些情况下，它可能会阻止进一步的多样化。古老杂交的原因、频率和后果仍有待探索。在这里，我们介绍了姜黄属（姜科）中几种古老杂交事件的情况，姜黄属是一种经济上重要的植物属，约有 130 个已知物种。我们分析了 37 种姜黄属植物的下一代测序获得的 1094 个靶向低拷贝基因和质体基因组，这些植物代表了已知的遗传多样性，并涵盖了该属的地理分布。通过系统发育网络分析，我们表明整个姜黄属及其最具多样性的谱系分别是通过与 Pyrgophyllum 属和一个已灭绝谱系的基因渗入而产生的。我们还记录了一个单一的古老杂交事件，其产物是 C. vamana，这代表了一个进化的死胡同。我们进一步讨论了这些杂交事件的不同情况，主要涉及亲本谱系的染色体数的（不）一致性。
