This study determined the sequences of chloro-plast DNA(cpDNA)trnL-F non-coding regions of indi-viduals of a tropical coniferous species,Dacrydium pectinatum,collected from 12 natural populations located in Hainan Pro...This study determined the sequences of chloro-plast DNA(cpDNA)trnL-F non-coding regions of indi-viduals of a tropical coniferous species,Dacrydium pectinatum,collected from 12 natural populations located in Hainan Province,southern China.Sequence length varied from 868 bp to 876 bp,indicating length polymorphism.Base com-position in the sequences was high in A+T content between 64.17%and 64.95%,and no recombination event occurred(Rm=0).Thirty haplotypes were identified based on statis-tical parsimony algorithm by running the TCS program.Populations of D.pectinatum in Hainan were lacking ge-netic differentiation.Such a deduction was supported by the observed FST values(0.00),AMOVA(24.17%of molecular variance attributed to difference among populations,P>0.05),high values of Nm(ranging from 1.92 to 2.50)and the branching structure in neighbor-joining(NJ)tree con-structed from haplotypes.A‘star-like’pattern was exhibited in the TCS network of trnL-F haplotypes,and majority of the haplotypes coalesced near the tips in NJ tree.Gene ge-nealogies of cpDNA haplotypes proposed a recent popula-tion expansion of D.pectinatum in Hainan,which was fur-ther supported by the results from Tajima’s D test and mis-match distribution analysis.Our data,in conjunction with geological and palynological evidences,showed that in the Holocene,due to global warming,refugee populations of D.pectinatum in Hainan might experience a range expan-sion.展开更多
针对热带树种陆均松Dacrydium pierrei de Laubenfels分布在海南的12个天然种群进行取样,测定了叶绿体DNA(cpDNA)trnL-F非编码区序列。序列长度介于868—876 bp.显示出长度多态性。碱基组成A+T含量较高,百分比值为64.17%-64.95%。通过...针对热带树种陆均松Dacrydium pierrei de Laubenfels分布在海南的12个天然种群进行取样,测定了叶绿体DNA(cpDNA)trnL-F非编码区序列。序列长度介于868—876 bp.显示出长度多态性。碱基组成A+T含量较高,百分比值为64.17%-64.95%。通过统计简约算法共鉴定出30个单倍型。根据种群间分化度FST(=0.00)、基因流Nm(介于1.92—2.50)、AMOVA(24.17%的遗传变异发生在种群间,P>0.05)以及邻接树中单倍型的分支式样,发现海南的陆均松种群尚未发生遗传分化。另一方面,依统计简约算法构建的单倍型网图具“星状”特征,而且邻接树中多数单倍型合并于树的顶端。这些基因谱系结果提示海南陆均松种群在近期历史上发生过种群扩张。Tajima的D检验和错配分析结果也支持这种推测。结合地质和古孢粉学证据,认为残存于“避难所”的陆均松种群在全新世时,伴随全球气候转暖,在海南岛内可能实行了扩张。展开更多
Random amplified polymorphic DNA (RAPD) markers were used to analyze genetic variation of Podocarpus imbricatus in Hainan Island and Mainland of China. Two populations of Dacrydium pierrei were used as comparison mate...Random amplified polymorphic DNA (RAPD) markers were used to analyze genetic variation of Podocarpus imbricatus in Hainan Island and Mainland of China. Two populations of Dacrydium pierrei were used as comparison materials. Both Podocarpus imbricatus and Dacrydium pierrei showed a low level of genetic diversity. However, Podocarpus imbricatus showed higher genetic diversity and higher population differentiation than Dacrydium pierrei. The geographic range may affect the genetic diversity of Podocarpus imbricatus and Dacrydium pierrei significantly. The UPGMA cluster tree showed that populations of Podocarpus imbricatus in Hainan Island and Guangxi Zhuang Autonomous Region were closer than those in Yunnan Province, indicating possible gene flow between Hainan Island and Guangxi Zhuang Autonomous Region. The young geological history of Hainan Island and the three times of unification and separation between Hainan Island and the Mainland may give the two species more possibilities of gene flow.展开更多
基金supported by the National Natural Science Foundation of China (Nos.30170789 and 30270153)the Natural Science Foundation of Guangdong Province,China (No.011125).
文摘This study determined the sequences of chloro-plast DNA(cpDNA)trnL-F non-coding regions of indi-viduals of a tropical coniferous species,Dacrydium pectinatum,collected from 12 natural populations located in Hainan Province,southern China.Sequence length varied from 868 bp to 876 bp,indicating length polymorphism.Base com-position in the sequences was high in A+T content between 64.17%and 64.95%,and no recombination event occurred(Rm=0).Thirty haplotypes were identified based on statis-tical parsimony algorithm by running the TCS program.Populations of D.pectinatum in Hainan were lacking ge-netic differentiation.Such a deduction was supported by the observed FST values(0.00),AMOVA(24.17%of molecular variance attributed to difference among populations,P>0.05),high values of Nm(ranging from 1.92 to 2.50)and the branching structure in neighbor-joining(NJ)tree con-structed from haplotypes.A‘star-like’pattern was exhibited in the TCS network of trnL-F haplotypes,and majority of the haplotypes coalesced near the tips in NJ tree.Gene ge-nealogies of cpDNA haplotypes proposed a recent popula-tion expansion of D.pectinatum in Hainan,which was fur-ther supported by the results from Tajima’s D test and mis-match distribution analysis.Our data,in conjunction with geological and palynological evidences,showed that in the Holocene,due to global warming,refugee populations of D.pectinatum in Hainan might experience a range expan-sion.
文摘针对热带树种陆均松Dacrydium pierrei de Laubenfels分布在海南的12个天然种群进行取样,测定了叶绿体DNA(cpDNA)trnL-F非编码区序列。序列长度介于868—876 bp.显示出长度多态性。碱基组成A+T含量较高,百分比值为64.17%-64.95%。通过统计简约算法共鉴定出30个单倍型。根据种群间分化度FST(=0.00)、基因流Nm(介于1.92—2.50)、AMOVA(24.17%的遗传变异发生在种群间,P>0.05)以及邻接树中单倍型的分支式样,发现海南的陆均松种群尚未发生遗传分化。另一方面,依统计简约算法构建的单倍型网图具“星状”特征,而且邻接树中多数单倍型合并于树的顶端。这些基因谱系结果提示海南陆均松种群在近期历史上发生过种群扩张。Tajima的D检验和错配分析结果也支持这种推测。结合地质和古孢粉学证据,认为残存于“避难所”的陆均松种群在全新世时,伴随全球气候转暖,在海南岛内可能实行了扩张。
基金the National Natural Science Foundation of China (Grant No.39830310)
文摘Random amplified polymorphic DNA (RAPD) markers were used to analyze genetic variation of Podocarpus imbricatus in Hainan Island and Mainland of China. Two populations of Dacrydium pierrei were used as comparison materials. Both Podocarpus imbricatus and Dacrydium pierrei showed a low level of genetic diversity. However, Podocarpus imbricatus showed higher genetic diversity and higher population differentiation than Dacrydium pierrei. The geographic range may affect the genetic diversity of Podocarpus imbricatus and Dacrydium pierrei significantly. The UPGMA cluster tree showed that populations of Podocarpus imbricatus in Hainan Island and Guangxi Zhuang Autonomous Region were closer than those in Yunnan Province, indicating possible gene flow between Hainan Island and Guangxi Zhuang Autonomous Region. The young geological history of Hainan Island and the three times of unification and separation between Hainan Island and the Mainland may give the two species more possibilities of gene flow.
