地理因素对箭竹复合体遗传多样性与遗传分化的影响

地理因素对植物天然居群的物种分布和种内分化具有重要影响。该研究通过对箭竹复合体内39个居群的14对SSR数据进行深入分析,旨在揭示重要地理因素(如海拔、纬度、地理距离)对该复合体内遗传多样性和遗传分化式样的影响。结果表明:(1)糙花箭竹亚支系遗传多样性最高(H_e=0.50),而团竹亚支系的遗传多样性最低(H_e=0.33)。(2)遗传多样性与纬度、海拔在A、B两个支系水平呈显著正相关关系,但在亚支系水平,遗传多样性的变化趋势呈现出更为复杂的局面,部分支系表现为负相关关系,推测纬度和海拔对箭竹复合体内遗传多样性水平具有一定影响,但也需重视其他进化因素的作用。(3)Mantel检验显示,仅在团竹亚支系中检测出较弱的正相关关系,表明地理距离不是影响箭竹复合体内遗传分化的主导因素,后续需结合基因流检测推断杂交事件对其遗传分化的影响。

Effect of Geographic Factors on the Genetic Diversity and Divergence of Fargesia spathacea Complex

Geographic factors play an important role in the species distribution and divergence of natural populations in plants. Here we re analyzed 14 SSR markers data in 39 populations from Fargesia spathacea complex, aimed to reveal how geographic factors may influence the pattern of genetic diversity and divergence of F. spathacea complex. The results showed that: (1) we found that F. scabrida sub clade exhibited the highest genetic diversity (H_e=0.50), while F. obliqua sub clade exhibited the lowest one (H_e=0.33). (2) On the level of clade A and B, genetic diversity was proved to be significantly positive correlated to altitude and latitude; but on the level of sub clade, we detected negatively correlations between genetic diversity and altitude, latitude, which indicated that some other factors may have an impact on the genetic diversity within F. spathacea complex. (3) We carried out Mantel test and found that geographic distance may not be the driving force of the current genetic divergence pattern within F. spathacea complex. Clade B showed no significant correlation between genetic distance and geographic distance, and only one sub clade in clade A showed slightly significant correlation. Future studies of gene flow may help answer whether hybridization influenced the genetic differentiation within these species.