PDF(Pubmed)
Abstract：
This study combined population genetics and parentage analysis to obtain foundational data for the conservation of Magnolia kwangsiensis. M. kwangsiensis is a Class I tree species that occurs in two disjunct regions in a biodiversity hotspot in southwest China. We assessed the genetic diversity and structure of this species across its distribution range to support its conservation management. Genetic diversity and population structure of 529 individuals sampled from 14 populations were investigated using seven nuclear simple sequence repeat (nSSR) markers and three chloroplast DNA (cpDNA) fragments. Parentage analysis was used to evaluate the pollen and seed dispersal distances. The nSSR marker analysis revealed a high genetic diversity in M. kwangsiensis, with an average observed (Ho) and expected heterozygosities (He) of 0.726 and 0.687, respectively. The mean and maximum pollen and seed dispersal distances were 66.4 and 95.7 m and 535.4 and 553.8 m, respectively. Our data revealed two distinct genetic groups, consistent with the disjunct geographical distribution of the M. kwangsiensis populations. Both pollen and seed dispersal movements help maintain genetic connectivity among M. kwangsiensis populations, contributing to high levels of genetic diversity. Both genetically differentiated groups corresponding to the two disjunct regions should be recognized as separate conservation units.
摘要：
本研究将群体遗传学和亲子关系分析相结合，以获得广玉兰保护的基础数据。广山是一类树种，分布在中国西南部生物多样性热点的两个不同地区。我们评估了该物种在其分布范围内的遗传多样性和结构，以支持其保护管理。使用七个核简单序列重复（nSSR）标记和三个叶绿体DNA（cpDNA）片段，研究了从14个种群中采样的529个个体的遗传多样性和种群结构。亲子关系分析用于评估花粉和种子的传播距离。nSSR标记分析揭示了广山的高遗传多样性，平均观察到的杂合度（Ho）和预期的杂合度（He）分别为0.726和0.687。花粉和种子的平均和最大传播距离分别为66.4和95.7m和535.4和553.8m，分别。我们的数据揭示了两个不同的遗传群体，与广山种群的分离地理分布一致。花粉和种子的传播运动都有助于维持广山种群之间的遗传连通性，有助于高水平的遗传多样性。与两个分离区域相对应的两个遗传分化组都应被视为单独的保存单元。
