Glacial Refugia of Ginkgo biloba and Human Impact on Its Genetic Diversity： Evidence from Chloroplast DNA

Variations in the trnK region of chloroplast DNA were investigated in the present study using polymerase chain reactionrestriction fragment length polymorphism to detect the genetic structure and to infer the possible glacial refugia of Ginkgo biloba L. in China. In total, 220 individuals from 12 populations in China and three populations outside China were analyzed, representing the largest number of populations studied by molecular markers to date. Nineteen haplotypes were produced and haplotype A was found in all populations. Populations in south-western China, including WC, JF, PX, and SP, contained 14 of the 19 haplotypes and their genetic diversity ranged from 0.771 4 to 0.867 6. The TM population from China also showed a high genetic diversity （H = 0.848 5）. Most of the genetic variation existed within populations and the differentiation among populations was low （GsT = 0.2）. According to haplotype distribution and the historical record, we suggest that populations of G. biloba have been subjected to extensive human impact, which has compounded our attempt to infer glacial refugia for Ginkgo. Nevertheless, the present results suggest that the center of genetic diversity of Ginkgo is mainly in south-western China and in situ conservation is needed to protect and preserve the genetic resources.     

Forest characteristics and population structure of Glyptostrobus pensilis,a globally endangered relict species of southeastern China

The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of G. pensilis in China have remained un-known up to now. We investigated six swamp forest stands and analyzed their forest community characteristics (i.e. vertical stratification, species composition, and diversity) and population structure, including the frequency distribution of DBH (diameter at breast height) and age-classes as found in Fujian Province, southeastern China. The vertical stratifications of all the forest stands were rather simple. The remaining wild specimens ranged from roughly 15 to some 357 years for an average of ca. 85 years, with only a few individuals less than 20 years old. Compared with the stands and populations of G. pensilis in Vietnam, the taxonomic compositions of the stands in the two regions were different, except for the dominant species-G. pensilis. The Shannon-Wiener index showed the overstory of each stand had much lower diversity (0.26 on average) in Fujian Province than that (1.97 on average) in Vietnam, whereas the diversity indices were about the same (around 2.41) for the understories in the two regions. Furthermore, we discovered 18 G. pensilis seedlings at the study sites in Fujian Province. This discovery demonstrates that G. pensilis regeneration is extremely poor and its populations are declining, although these populations are rela-tively healthier than those in Vietnam.     

Microsatellite analysis of genetic diversity and population structure of Chinese mitten crab （Eriocheir sinensis）

Chinese mitten crab (Eriocheir sinensis) has higher commercial value as food source than any other species of Eriocheir in China.To evaluate the germplasm resources and characterize the genetic diversity and population structure of the crabs in different water systems,two stocks and two farming populations were assessed with 25 polymorphic microsallite loci available in public GenBank.Basic statistics showed that the average observed heterozygosity (Ho) amongst populations ranged from 0.5789 to 0.6824.However,a remarkable presence of inbreeding and heterozygote deficiencies were observed.To analyze population structure,pairwise FST coefficients explained only ～10.3% variability from the subdivision of mitten crab populations,the remaining variability stems from the subdivision within subpopulations.Although the four populations had slight differentiation,different allelic frequencies resulted in distinct population structures.Two stocks and one farming population were clustered together to the phylogenetic branch of Yangtze crab,with an approximate membership of 95%.Whereas,another fanning population was clustered singly to the phylogenetic branch of the Liaohe crab,with a membership of 97.1%.The tests for individual admixture showed that Yangtze crab had probably been contaminated with individuals from other water systems.Genetic relationships between populations also supported the conclusion that Yangtze crab and Liaohe crab had different gene pools in spite of the origins of the same species.     

从线粒体基因探讨中国大头蛙群的分类及其属内地位

Partial sequences of the mitochondrial 12S rRNA and 16S rRNA gene were determined for 8 populations of three species of Chinese Limnonectes, and aligned with the published sequences of Limnonectes from other parts of the world. When Nanorana parker, Paa boulengeri, Fejervarya limnocharis and Hoplobatrachus rugulosus was used as outgroup taxa (Accession Nos. AY158705, AY313685, AF206111, AF206491, AY322311). The sequences of the 12S rRNA and 16S rRNA genes totaled 950 nueleotide positions with gaps including 510 variable sites. We reconstructed phylogenetie trees using Clustal X 1.8, Mega 2.1 and PHYLIP 3.5e software, and using the maximum parsimony and maximum likelihood methods, respectively. Our analyses suggest that these fanged frogs from China are another monophyletie group in addition to the four monophyletie groups identified by previous studies. The Chinese Limnonectes were grouped into three elades (BCL 55% ). The first elade contains one species (BCL 100% ), from a population of Limnoneetes fragilis from Hainan Province. The second contains four individuals (BCL 100% ), i. e. two populations of Limnonectes kuhlii from Yunnan Province. The third contains one species (BCL 100% ), i. e. five populations of Limnonectes fujianensis from Fujian Province and 1 from Taiwan Province. The resulted phylogenetie trees indicate L. fragilis is basal to L. kuhlii L. fujianensis 。     

Genetic structure of Pallas’s squirrel (Callosciurus erythraeus) populations from artificial forests in Hongya County, Sichuan, China

To understand levels of population differentiation in Pallas’s squirrel (Callosciurus erythraeus) in fragmented habitats, we collected 83 samples from three patches of artificial forest in Hongya County, Sichuan Province, China. Sample numbers from each patch were as follows: 16 from Hanwang (HW), 27 from Muchansi (MCS) and 40 from Yanyandong (YYD). The mitochondrial DNA control region was sequenced and 18 haplotypes were observed. Our results showed that haplotype diversities of the three C. erythraeus populations were similar (0.771, 0.791 and 0.733). Fixation indices (F_st) of pairwise populations were between 0.21 and 0.31, and the estimated gene flow (Nm) was between 1 and 2. Analysis of molecular variance (AMOVA) showed that most molecular variation occurred within populations (74.82%); variances among populations were small but there was significant genetic differentiation. In addition, the neighbour-joining (NJ) tree showed three clades in the phylogenetic tree for population genetic structure. This was confirmed by the median-joining haplotype network. Furthermore, analysis of isolation by distance (IBD) showed that genetic differentiation among the three populations was positively related to geographical distance. However, tests of neutrality and the observed mismatch distribution of pairwise differences between sequences indicated that C. erythraeus populations were relatively stable in the past.     

Analysis of the genetic diversity of Bemisia tabaci populations in Shanxi province, China☆

Five different primer combinations were used for the analysis of 152 B biotype Bemisia tabaci (Gennadius) individuals and five Trialeurodes vaporairiorum individuals collected from 19 counties and seven host plants in Shanxi province in China, respectively. The main objective of the present study was to use AFLP markers to determine the genetic diversity of B. tabaci populations collected from Shanxi Province. The use of these primer combinations allowed the identification of 127 polymorphic bands (52.26%) from 60 to 500 bp. The average number of polymorphic bands per primer was 25.4 while the range for the five primers was 20–32. The average degree of heterozygosity was 0.251, while the range for the five primers was 0.204–0.289. The results suggested definite genetic diversity among different B. tabaci populations. Cluster analysis showed that B. tabaci populations were firstly scattered to three genetic groups according to the regions, then every genetic group was scattered to several subgroups according to the host plants, which revealed the genetic variability of B biotype B. tabaci populations has been not only among different regions, but also among different host plants in Shanxi Province.     

Genetic structure of Pallas’s squirrel (Callosciurus erythraeus) populations from artificial forests in Hongya County, Sichuan, China

To understand levels of population differentiation in Pallas’s squirrel (Callosciurus erythraeus) in fragmented habitats, we collected 83 samples from three patches of artificial forest in Hongya County, Sichuan Province, China. Sample numbers from each patch were as follows: 16 from Hanwang (HW), 27 from Muchansi (MCS) and 40 from Yanyandong (YYD). The mitochondrial DNA control region was sequenced and 18 haplotypes were observed. Our results showed that haplotype diversities of the three C. erythraeus populations were similar (0.771, 0.791 and 0.733). Fixation indices (F_st) of pairwise populations were between 0.21 and 0.31, and the estimated gene flow (Nm) was between 1 and 2. Analysis of molecular variance (AMOVA) showed that most molecular variation occurred within populations (74.82%); variances among populations were small but there was significant genetic differentiation. In addition, the neighbour-joining (NJ) tree showed three clades in the phylogenetic tree for population genetic structure. This was confirmed by the median-joining haplotype network. Furthermore, analysis of isolation by distance (IBD) showed that genetic differentiation among the three populations was positively related to geographical distance. However, tests of neutrality and the observed mismatch distribution of pairwise differences between sequences indicated that C. erythraeus populations were relatively stable in the past.     

Polymorphic Alu insertions and their associations with MHC class I alleles and haplotypes in Han and Jinuo populations in Yunnan Province, southwest of China

The associations of polymorphic Alu insertions （POALINs） with major histocompatibility complex （MHC） class I genes enable us to better identify origins and evolution of MHC class I region haplotypes in different populations. For further studying origins and evolution of MHC class I region haplotypes in Han and Jinuo populations in Yunnan Province, we investigated frequencies of five POALINs, their associations with HLA-A and -B, the three-loci POALINs haplotype frequencies and HLA/POALIN four-loci haplotype frequencies within the alpha block of MHC class I region. We found that a strong positive association between AluHG and HLA-A＊02 is in Jinuo, but not in Yunnan Han. These results suggest that MHC class I region haplotypes of the two studied populations might derive from different progenitor haplotypes and MHC I-POALINs are informative genetic markers for investigating origins and evolution of MHC class I region haplotypes in different populations.     

Seasonal changes of resistance to fenvalerate and cypermethrin in the larval parasitoid Cotesia plutellae （Hymenoptera： Braconidae）

The seasonal changes of insecticide resistance and stability in hymenopteran Cotesia plutellae, collected from Jianxin, Fuzhou-City, and Shangjie, Minhou-County, Fujian, China, were assessed by using a dry residual film method. The resistance to two insecticides in the field populations of C. plutellae was not stable under insecticide-free conditions in the insectarium. Compared with susceptible F11 progeny of C. plutellae in the insectarium, the resistance ratios （RR） in F0 parents were 18.4 for fenvalerate and 11.4 for cypermethrin based on LC50 at 9 hours, and 32.8 for fenvalerate and 28.5 for cypermethrin based on LC50 at 24 hours when the parasitoids were left in contact with the insecticides for 1 hour and mortalities were recorded at 9 and 24 hours, respectively. However, the RR in a field population of C. plutellae were 9.2 for fenvalerate and 12.7 for cypermethrin, if the parasitoids were left in contact with the insecticides for 24 hours. The resistances to the two pyrethroids in other field populations collected from Jianxin and Shangjie from November 2000 and July 2004 were also determined. Significant seasonal variations of resistance to the two insecticides in the field populations of C. plutellae were found. The RR were 3.0-18.4 for fenvalerate and 4.8-20.6 for cypermethrin in Jianxin populations from November 2000 to April 2002 based on LC50 at 9 h, and 2.3-13.6 for fenvalerate and 3.6-16.0 for cypermethrin in Shangjie populations from May 2002 to July 2004 based on LC50 at 24 hours. The resistance levels were high in spring and autumn and decreased sharply in summer. In addition, significant recovery from the knocked-down caused by the insecticides was found in the F0 and field populations of C. plutellae which were resistant to fenvalerate and cypermethrin if the parasitoids were left in contact with the pyrethroids for 1 hour. However, no recovery was found in susceptible F11 progeny.     

Molecular Assessment and Taxonomic Status of the Rapid Racerunner （Eremias velox complex） with Particular Attention to the Populations in Northwestern China

The rapid racerunner,Eremias velox,is a widely distributed lizard from the northern Caucasus across entire Central Asia eastward to China.It is increasingly common to accept E.velox as a species complex in its entire range.To date,published morphological and molecular systematic hypotheses of this complex are only partially congruent,and its taxonomic status and evolutionary history are still far from clear.The mitochondrial cytochrome b gene and12S rRNA sequences were used to evaluate the taxonomy of this complex,with particular attention to the phylogenetic placement of populations in northwestern China.Examination of the phylogenetic analyses recovers seven distinct,biogeographically discrete,and well-supported clades,revealing genetically identifiable populations corresponding to some previously morphology-defined subspecies.Chinese E.v.roborowskii appears to have split from other Central Asian rapid racerunner lizards well before differentiation occurred among the latter taxa.Specifically,we corroborate that there are two subspecies occurring in China,i.e.,E.v.velox and E.v.roborowskii.We recommend a novel subspecific status for the phenotypically and genetically distinct populations in southern Aral Sea region of Uzbekistan previously assigned to E.v.velox.Finally,each of the three independently evolving lineages from Iranian Plateau should be recognized as three species new to science under the general lineage concept.     

Call Characteristic Network Reveal Geographical Patterns of Call Similarity:Applying Network Analysis to Frog’s Call Research

Individual’s phenotypic traits are the results of adaptation to ecological conditions.Therefore,different selection pressures caused by heterogeneous environments may result in phenotypic difference,especially for individuals in different geographical populations.Here,we illustrated for the first time to use social network analysis(SNA)for examining whether geographical proximity predicts the similarity patterns in call characteristics among populations of an anuran species.We recorded calls from 150 male dorsal-striped opposite-fingered treefrogs(Chiromantis doriae)at 11 populations in Hainan Province and one population in Guangdong Province in China's Mainland,and we measured eight acoustic variables for each male.Mantel test didn’t show a correlation between geographical proximity and the similarity in call characteristics among populations.In addition,we failed to find correlations between a population’s eigenvector centrality and the distance to its nearest neighbor,nor between the coefficient of variation of similarity in call characteristics of a population and the average distance to all other populations.Nevertheless,three acoustic clusters were identified by the Girvan-Newman algorithm,and clustering was partially associated with geography.Furthermore,the most central populations were included in the same cluster,but the top betweenness populations were located within different clusters,suggesting that centrality populations are not necessary bridging between clusters.These results demonstrate the potential usefulness of the SNA toolbox and indicate that SNA helps to uncover the patterns that often overlooked in other analytical methods.By using SNA in frog’s call studies,researchers could further uncover the potential relationship in call characteristics between geographical populations,further reveal the effects of ecological factors on call characteristics,and probably enhance our understanding of the adaptive evolution of acoustic signals.     

Karyotype and cytogeography of the genus Heracleum （Apiaceae） in the Hengduan Mountains

In the present study, the karyotypes of 34 populations belonging to 11 species and one variety of Heracleum from the Hengduan Mountains in China were examined. Chromosome numbers and the karyotypes of three species （H. souliei, H. la＇ngdoni, and H. wenchuanense） are reported for the first time, as are the karyotypes of H. moellendorffii and H. henryi （tetraploid）. Populations of H. candicans, H. franchetii, and H. kingdoni in the Hengduan Mountains were found to consist of a mixture of diploid and tetraploid plants. Except for four species of Heracleum, namely H. candicans, H. franchetii, H. henryi, and H.kingdoni, which have both diploid and tetraploid karyotypes, all other species of Heracleum are were found to be diploid. All karyotypes were found to belong to the 2A type of Stebbins, with the exception ofH. candicans var. obtusifolium, which belongs to 2B, and H. hemsleyanum and H. franchetii （Mt. Dujuan, Daocheng, Sichuan, China）, which belong to 1A. There was only a slight difference in the karyotype asymmetry index, which suggests a close kinship for species of Heracleum and that the entire phylogenetic development of Heracleum is relatively primitive. Species that exhibited advanced morphological features were also more advanced in karyotype structure, with the order ofkaryotype evolution being 1A→2A→2B. This phenomenon indicates that the species distributed in the Hengduan Mountains have not diverged completely and that the Hengduan Mountains are a relatively young and active area for the evolution of Heracleum. Polyploidization in Heracleum may be an important evolutionary mechanisms for some species, generating diversity. The biological attributes, distribution range, and the geological history of the genus have all played a part in accelerating the evolution through polyploidization or aneuploidization. It is known that as the distribution latitude of Heracleum decreases from north to south, the chromosome number, ploidy level, and asymmetry structure appear to increase. In the Hengd     

Phylogenetic Analysis of Brine Shrimp （Artemia） in China Using DNA Barcodinge

DNA barcoding is a powerful approach for characterizing species of organisms, especially those with almost identical morphological features, thereby helping to to establish phylogenetic relationships and reveal evolutionary histories. In this study, we chose a 648-bp segment of the mitochondrial gene, cytochrome c oxidase subunit 1 （COI）, as a standard barcode region to establish phylogenetic relationships among brine shrimp （Artemia） species from major habitats around the world and further focused on the biodiversity of Artemia species in China, especially in the Tibetan Plateau. Samples from five major salt lakes of the Tibetan Plateau located at altitudes over 4,000 m showed clear differences from other Artemia populations in China. We also observed two consistent amino acid changes, 153A/V and 183L/F, in the COI gene between the high and low altitude species in China. Moreover, indels in the COI sequence were identified in cyst and adult samples unique to the Co Qen population from the Tibetan Plateau, demonstrating the need for additional investigations of the mitochondrial genome among Tibetan Artemia populations.     

Molecular evolution of influenza A (H3N2) viruses circulated in Fujian Province, China during the 1996–2004 period

We studied the genetic and epidemic characteristics of influenza A (H3N2) viruses circulated in human in Fujian Province, south of China from 1996 to 2004. Phylogenetic analysis was carried out for genes encoding hemagglutinin1 (HA1) of influenza A virus (14 new and 11 previously reported reference se-quences). Our studies revealed that in the 8 flu seasons, the mutations of HA1 genes occurred from time to time, which were responsible for about four times of antigenic drift of influenza H3N2 viruses in Fujian, China. The data demonstrated that amino acid changes were limited to some key codons at or near antibody binding sites A through E on the HA1 molecule. The changes at the antibody binding site B or A or sialic acid receptor binding site 226 were critical for antigenic drift. But the antigenic sites might change and the key codons for antigenic drift might change as influenza viruses evolve. It seems important to monitor new H3 isolates for mutations in the positively selected codons of HA1 gene in south of Asia.     

Analysis of the genetic diversity of Bemisia tabaci populations in Shanxi province, China

Five different primer combinations were used for the analysis of 152 B biotype Bemisia tabaci (Gennadius) individuals and five Trialeurodes vaporairiorum individuals collected from 19 counties and seven host plants in Shanxi province in China, respectively. The main objective of the present study was to use AFLP markers to determine the genetic diversity of B. tabaci populations collected from Shanxi Province. The use of these primer combinations allowed the identification of 127 polymorphic bands (52.26%) from 60 to 500 bp. The average number of polymorphic bands per primer was 25.4 while the range for the five primers was 20–32. The average degree of heterozygosity was 0.251, while the range for the five primers was 0.204–0.289. The results suggested definite genetic diversity among different B. tabaci populations. Cluster analysis showed that B. tabaci populations were firstly scattered to three genetic groups according to the regions, then every genetic group was scattered to several subgroups according to the host plants, which revealed the genetic variability of B biotype B. tabaci populations has been not only among different regions, but also among different host plants in Shanxi Province.     

RAPD diversity of Stipa grandis populations and its relationship with some ecological factors

The genetic diversity of Stipa grandis P.Smirn and its relationship with the climatic variables were studied using the RAPD technique for 90 genes from five natural populations sampled in the Xilingol steppe, China. Sixteen oligonucleotides screened from 100 random primers were used to amplify 310 trackable RAPD loci, which were all polymorphic. By analyzing the RAPD data using POPGENE software, different geographic S. grandis populations were studied, which indicated a high level of genetic diversity, and the maximum variation was observed within the populations with a 28% variation observed among the populations. Using Pearson correlation analysis, significant (P < 0.05) or highly significant (P < 0.01) relationships were found between gene diversity indexes and temperature factors (≥10°C cumulative temperature in a year, annual mean temperature and mean temperature in January). Mantel's tests showed that there was no significant correlation between Nei's unbiased genetic distance and the geographic distance of S. grandis populations (r = 0.184, P = 0.261). However, there were significant or highly significant correlations between Nei's genetic distance and the several climatic divergences in pairwise S. grandis populations. All results indicated that natural selection resulting from variations in water and temperature was responsible for the adaptive eco-geographical differentiation indicated by the RAPD markers of different S. grandis populations, and that immigration and gene drift did not play an important role in affecting the differentiation of S. grandis populations.     

Toxicological and biochemical characterizations of malathion sensitivity in two field populations of Oxya chinensis （Orthoptera： Acridoidea）

We evaluate comparative toxicity of malathion in the two populations of the grasshopper Oxya chinensis, collected from Daixian and Fanshi of Shanxi province, China. General esterases and acetylcholinesterase （ACHE） from the two populations were characterized and compared. LD50 of the Daixian population （7.58 μg/g body weight） was 2.02-fold higher than that of the Fanshi population （3.75μg/g body weight）. General esterase-specific activities in the Daixian population were 1.91,130 and 1.85-fold higher than those in the Fanshi population, when α-NA, α-NB and β-NA were used as a substrate, respectively. Kinetic studies of general esterase showed that Vmax values of general esterases hydrolyzing α-NA,α-NB and β-NA in the Daixian population were 2.15-, 1.12-, and 1.47-fold, respectively, higher than those in the Fanshi population. The AChE activity of the Fanshi population was 1.54-fold higher than that of the Daixian population. Kinetic analysis of AChE showed that significant differences were presented between the two populations in the Km values; and the Vmax value in the Fanshi population was higher than that in the Daixian population. Inhibition studies of AChE indicated that AChE from the Daixian population was 2.56-, 2.80-, and 2.29-fold less sensitive to inhibition by paraoxon, chlorpyrifos-oxon, and demeton-S-methyl, respectively, than that from the Fanshi population. These biochemical characterizations of general esterases and AChE were consistent with malathion bioassay in the two populations. It is inferred that the reduced sensitivity of altered AChE and increased general esterase activities play an important role in the differences of insusceptibility of Oxya chinensis to malathion between the two populations.     

Two genetically distinct units of Sinomanglietia glauca （Magnoliaceae） detected by chloroplast PCR-SSCP

Sinomanglietia glauca is a critically endangered species described from Jiangxi Province in the 1990s. Recently two populations were discovered from Yongshun County of west Hunan Province, about 450 km away from those in Jiangxi. Because of the new findings and the poor reproducibility inherent to RAPD and ISSR markers of previous studies, the population structure of this rare species was reanalyzed with chloroplast PCR-SSCP （single-stranded conformation polymorphism）, including all of four recorded populations. The results showed that two distinct haplotypes characterized Jiangxi and Hunan populations separately, with no genetic variation occurring within regions. We postulated that this surprising pattern might result from habitat fragmenta- tion and demographic bottlenecks during and/or after the Quaternary glaciation. On the basis of the pronounced genetic structure, two evolutionarily significant units （ESUs） were recommended for effective conservation of S. glauca.     

A study on population genetic structure of Oryza meyeriana (Zoll. et Mor. ex Steud.) Baill. from Yunnan and its in situ conservation significance

In order to determine genetic diversity of Oryza meyeriana (Zoll. et Mor. ex Steud. ) Baill., 12 enzyme systems encoded by 17 loci were electrophoretically analyzed in 164 individuals of seven populations from Simao Prefecture, Yunnan Province, China. In comparison with those seed plants with the same life history and breeding systems, as well as the other species in the genus Oryza, the species shows rather low levels of genetic diversity (A = 1.1, P = 8.0%, Ho = 0.004 and He = 0. 015) within populations and high genetic differentiation among populations. FST was up to 0. 649, suggesting that 64. 9% of total genetic variability exists among populations. Considering high genetic differentiation among populations from a limited geographic region, most of the populations of the species are worth being protected, and therefore, great natural protection regions should theoretically be established in which a great deal of populations should be involved for developing in situ conservation management. Meanwhile     

Molecular phylogeography and evolutionary history of Picea likiangensis in the Qinghai-Tibetan Plateau inferred from mitochondrial and chloroplast DNA sequence variation

The aim of the present study was to examine the phylogeographic and evolutionary history of Picea likiangensis,a dominant species of the conifer forests in the eastern declivity of the Qinghai-Tibetan Plateau. We collected 422 individuals from 42 natural populations of three major varieties classified under this species.In conifers,mitochondrial(mt) DNA and chloroplast(cp) DNA dispersed by seeds or pollen experience very different levels of gene flow.To this end,we examined the sequence variation of two mtDNA fragments(nad5 intron 1 and nad1 intron b/c) and three cpDNA fragments(trnL-trnF,trnS-trnG and nadhK/C).We found that cpDNA probably introgressed from P.purpurea into remote populations of P.likiangensis through long-distance dispersal. Multiple refugia seem to have been maintained for P.likiangensis during the Last Glacial Maximum because the cpDNA and mtDNA haplotypes recovered were fixed in the different regions.Postglacial expansions were only detected at the distributional edges of this species where a single cpDNA or mtDNA haplotype was fixed in adjacent populations.However,genetic imprints of postglacial expansions from these two sets of markers were different in the western and southeastern regions,which may result from the long-distance dispersal of the cpDNA,as well as its fast lineage sorting during intraspecific divergences.Analysis of molecular variance further suggested that genetic differentiation between the three varieties is higher at cpDNA markers than at mtDNA markers,which supports the previous viewpoint that cpDNA markers with a high rate of gene flow may be more effective in delimitating closely related taxa.Together,the results of the present study highlight the evolutionary complexity of a widely distributed species owing to interactions among local and edge expansion,long-distance dispersal,and intraspecific divergences at two sets of DNA genomes with different rates of gene flow.