Du Shuhui, Hu Xiaoyan, Yang Xiuyun, Yu Wendong, Wang Zhaoshan
College of Forestry, Shanxi Key Laboratory of Cultivation and Development on Functional Oil Trees in the Northern China Shanxi Agricultural University Taigu Jinzhong China.
College of Horticulture and Plant Protection Yangzhou University Yangzhou China.
Ecol Evol. 2022 Jul 24;12(7):e9101. doi: 10.1002/ece3.9101. eCollection 2022 Jul.
Phylogeographic research concerning Central China has been rarely conducted. Population genetic and phylogeography of var. (also called sour jujube) were investigated to improve our understanding of plant phylogeographic patterns in Central China. Single-copy nuclear gene markers and complete chloroplast genome data were applied to 328 individuals collected from 21 natural populations of sour jujube in China. Nucleotide variation of sour jujube was relatively high ( = 0.00720, = 0.00925), which resulted from the mating system and complex population dynamics. Analysis of molecular variation analysis revealed that most of the total variation was attributed to variation within populations, and a high level of genetic differentiation among populations was detected ( = 0.197). Relatively low long-distance dispersal capability and vitality of pollen contributed to high genetic differentiation among populations. Differences in the environmental conditions and long distance among populations further restricted gene flow. Structure clustering analysis uncovered intraspecific divergence between central and marginal populations. Migrate analysis found a high level of gene flow between these two intraspecific groups. Bayesian skyline plot detected population expansion of these two intraspecific groups. Network and phylogeny analysis of chloroplast haplotypes also found intraspecific divergence, and the divergence time was estimated to occur at about 55.86 Ma. Haplotype native to the Loess Plateau was more ancient, and multiple glacial refugia of sour jujube were found to locate at the Loess Plateau, areas adjacent to the Qinling Mountains and Tianmu Mountains. Species distribution model analysis found a typical contraction-expansion model corresponding to the Quaternary climatic oscillations. In the future, the distribution of sour jujube may shift to high-latitude areas. This study provides new insights for phylogeographic research of temperate plant species distributed in Central China and sets a solid foundation for the application of the scientific management strategy of var. .
关于中国中部的系统发育地理学研究很少开展。对酸枣变种（也称为酸枣）进行了种群遗传学和系统发育地理学研究，以增进我们对中国中部植物系统发育地理格局的理解。将单拷贝核基因标记和完整叶绿体基因组数据应用于从中国21个酸枣自然种群收集的328个个体。酸枣的核苷酸变异相对较高（π = 0.00720，θ = 0.00925），这是由交配系统和复杂的种群动态导致的。分子变异分析表明，总变异的大部分归因于种群内变异，并且检测到种群间存在高水平的遗传分化（FST = 0.197）。相对较低的长距离扩散能力和花粉活力导致了种群间的高遗传分化。种群间环境条件的差异和远距离进一步限制了基因流动。结构聚类分析揭示了中部和边缘种群之间的种内分化。迁移分析发现这两个种内群体之间存在高水平的基因流动。贝叶斯天际线图检测到这两个种内群体的种群扩张。叶绿体单倍型的网络和系统发育分析也发现了种内分化，分化时间估计约为5586万年前。黄土高原原生的单倍型更为古老，并且发现酸枣的多个冰期避难所位于黄土高原、秦岭和天目山附近地区。物种分布模型分析发现了一个与第四纪气候振荡相对应的典型收缩 - 扩张模型。未来，酸枣的分布可能会向高纬度地区转移。本研究为分布于中国中部的温带植物物种的系统发育地理学研究提供了新见解，并为酸枣变种科学管理策略的应用奠定了坚实基础。
