中文摘要：

以群落学方法和谱系地理学方法,分析广东省南昆山与大岭山珍稀孑遗植物伯乐树种群之间的关系,揭示它们的遗传结构并比较所处群落的异质性。群落分析发现,南昆山和大岭山伯乐树所在群落无论在区系成分上还是在物种组成上均表现出极大相似性,同时也稍有差异：大岭山伯乐树所在群落的物种多样性不及南昆山;两群落内伯乐树种群龄级结构均不完整,而南昆山伯乐树种群相对表现出更强的生活力。谱系地理分析发现,南昆山和大岭山伯乐树种群的单倍型多样性（hd）分别为0.682和0,核苷酸多样性（π）分别为0.181×10-3和0,两种群间的遗传分化系数GST=0.167,基因交流系数Nm=2.49。研究表明,南昆山和大岭山伯乐树种群为复合种群,南昆山伯乐树种群起源可能更为古老。南昆山伯乐树种群单倍型多样性和核苷酸多样性较之大岭山伯乐树种群为高,更具保护价值。

英文摘要：

Chloroplast DNA（cpDNA）markers and community analysis methods were used to determine the relation-ship between populations of rare and relic plant Bretschneidera sinensis in Nankun Mountain and Daling Mountain and to identify the genetic structure and community feature differences. Community analysis revealed a strong similarity between the two populations in both floristic elements and species compositions, while also implied differences in species diversity, which was much greater in Nankun Mountain. The age structures of B. sinensis in the two communities were incomplete, and the population in Nankun Mountain showed greater vital force. Phylogeographical analyses indi-cated that the haplotype diversity（hal）of populations in Nankun and Daling Mountains was 0. 682 and 0 respectively, and the nucleotide diversity（n）was 0. 181×10^-3 and 0 respectively. Gsrand Nm between the two populations were 0. 167 and 2.49 respectively. The study indicated that the two populations represented a metapopulation, and the origin of the B. sinensis population in Nankun Mountain might be more primitive. Both haplotype diversity and nucleotide diversity of B. sinensis were much higher in Nankun Mountain than in Daling Mountain; therefore, the conservation of B. sinensis in Nankun Mountain should be of higher significance.