Wu Di, Meng Ying, Wen Jun, Nie Ze-Long
Key Laboratory of Plant Resources Conservation and Utilization, College of Biological Resources and Environmental Sciences, Jishou University, Jishou, Hunan, China.
Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC, United States.
Front Plant Sci. 2025 Jun 25;16:1521784. doi: 10.3389/fpls.2025.1521784. eCollection 2025.
Knowledge of historical distribution and postglacial phylogeographic evolution of plants is important for better understanding their current distribution, population structure and potential fate in the future. Surprisingly, little is known about the post-glacial recolonization history of lianas that are widely distributed in the deciduous or mixed deciduous-evergreen forests in North America. Here, we conducted a phylogeographic study on 47 populations with 398 individuals from the North American using both chloroplast and nuclear DNA sequences data. A high level of genetic diversity is observed among populations in North America, with 66.45% of cpDNA and 92.78% of nrDNA genetic variation present within populations. The North American is roughly grouped into three main lineages with a south to north trend of decline in genetic diversity, which may have been isolated and diverged due to climatic and geographic environmental influences since the late Miocene. Our results indicate that a wide range of gene flow and frequent hybridization are occurring among the populations and the Edwards Plateau, the southern Appalachian Mountains and the Atlantic coastal plains are their possible glacial refugia in eastern and southern North America. The results for represent the first phylogeographic analysis of a major lineage of temperate woodland climbers in North America and support the importance of long-distance dispersal events leading to extensive hybridization and gene flow during the post-glacial migration of this plant lineage.
了解植物的历史分布和冰期后系统发育地理学演化对于更好地理解它们当前的分布、种群结构以及未来的潜在命运至关重要。令人惊讶的是，对于广泛分布于北美落叶林或落叶常绿混交林的藤本植物的冰期后重新定殖历史，我们知之甚少。在此，我们利用叶绿体和核DNA序列数据，对来自北美的47个种群、398个个体进行了系统发育地理学研究。在北美种群中观察到了高水平的遗传多样性，66.45%的叶绿体DNA（cpDNA）和92.78%的核核糖体DNA（nrDNA）遗传变异存在于种群内部。北美种群大致分为三个主要谱系，遗传多样性呈现出自南向北下降的趋势，自中新世晚期以来，可能由于气候和地理环境的影响而被隔离并分化。我们的结果表明，该植物种群之间存在广泛的基因流动和频繁的杂交现象，爱德华兹高原、阿巴拉契亚山脉南部和大西洋沿岸平原可能是它们在北美东部和南部的冰期避难所。这些结果代表了对北美温带林地攀缘植物一个主要谱系的首次系统发育地理学分析，并支持了在该植物谱系冰期后迁移过程中长距离扩散事件导致广泛杂交和基因流动的重要性。
