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Abstract：
The taxonomic classification of Picea meyeri and P. mongolica has long been controversial. To investigate the genetic relatedness, evolutionary history, and population history dynamics of these species, genotyping-by-sequencing (GBS) technology was utilized to acquire whole-genome single nucleotide polymorphism (SNP) markers, which were subsequently used to assess population structure, population dynamics, and adaptive differentiation. Phylogenetic and population structural analyses at the genomic level indicated that although the ancestor of P. mongolica was a hybrid of P. meyeri and P. koraiensis, P. mongolica is an independent Picea species. Additionally, P. mongolica is more closely related to P. meyeri than to P. koraiensis, which is consistent with its geographic distribution. There were up to eight instances of interspecific and intraspecific gene flow between P. meyeri and P. mongolica. The P. meyeri and P. mongolica effective population sizes generally decreased, and Maxent modeling revealed that from the Last Glacial Maximum (LGM) to the present, their habitat areas decreased initially and then increased. However, under future climate scenarios, the habitat areas of both species were projected to decrease, especially under high-emission scenarios, which would place P. mongolica at risk of extinction and in urgent need of protection. Local adaptation has promoted differentiation between P. meyeri and P. mongolica. Genotype‒environment association analysis revealed 96,543 SNPs associated with environmental factors, mainly related to plant adaptations to moisture and temperature. Selective sweeps revealed that the selected genes among P. meyeri, P. mongolica and P. koraiensis are primarily associated in vascular plants with flowering, fruit development, and stress resistance. This research enhances our understanding of Picea species classification and provides a basis for future genetic improvement and species conservation efforts.
摘要：
云杉和蒙古云杉的分类学分类长期以来一直存在争议。为了调查遗传相关性，进化史,和这些物种的种群历史动态，基因分型测序（GBS）技术用于获得全基因组单核苷酸多态性（SNP）标记，随后被用来评估人口结构，人口动态，和适应性分化。在基因组水平上的系统发育和种群结构分析表明，尽管蒙古假单胞菌的祖先是M.meyeri和M.koraiensis的杂种，蒙古云杉是一种独立的云杉物种。此外,蒙古P与P.meyeri的关系比与M.koraiensis的关系更密切，这与它的地理分布是一致的。在P.meyeri和P.mongolica之间有多达八个种间和种内基因流实例。P.meyeri和P.mongolica的有效种群规模普遍减少，Maxent模型显示，从最后一次冰川最大值(LGM)到现在，它们的栖息地面积最初减少，然后增加。然而,在未来的气候情景下，两种物种的栖息地面积预计都会减少，特别是在高排放的情况下，这将使蒙古假单胞菌面临灭绝的危险，迫切需要保护。局部适应促进了P.meyeri和P.mongolica之间的分化。基因型-环境关联分析揭示了96,543个与环境因素相关的SNP，主要与植物对水分和温度的适应有关。选择性扫描显示，在P.meyeri中选择的基因，蒙古假单胞菌和红单胞菌主要在维管植物中与开花有关，果实发育,和抗压力。这项研究增强了我们对云杉物种分类的理解，并为未来的遗传改良和物种保护工作提供了基础。
