|
|
|
|
|
|
|
|
|
|
|
|
资助项目
GST, P < 0.05) were exhibited by this species. The SAMOVA revealed seven diverging groups of related chlorotypes, six of them had distinct nonoverlapping geographical ranges: one in the northeast comprising 10 populations, a second with a southeast distribution comprising 22 populations, and the remaning four groups comprising 15 populations located in the west part of the species’ range along different river valleys. The genetic clustering of populations into three regions was also supported by analysis of molecular variance, which showed that most genetic variation (82.43%) was found among these three regions. Two clusters were distinguished by both phylogenetic analysis and genealogical analysis of chlorotypes, one consisting of chlorotypes from the western region and the second consisting of those from the eastern region. Significant genetic differences between the two regions might be attributed to vicariance and restricted gene flow, and this vicariance could be explained by the physical environmental heterogeneity on each side of the Tanaka-Kaiyong Line. Following the uplift of the Tibetan Plateau, the reorganization of the major river drainages was primarily caused by river separation and capture events. These historical events could change the distribution of S. davidii from fragmented to continuous (Upper/Lower Jinshajiang and Yalongjiang/Daduhe), and from continuous to fragmented (Nujiang and Jinshajiang/Honghe). However, spatial and temporal patterns of phylogeographic divergence are strongly associated with historical disjunction rather than modern drainage connections. Moreover, the following north-south split in the eastern region and effective isolation with their genetic diversity were essentially modelled by genetic drift. The higher chlorotype richness and genetic divergence for populations in western region compared with other two regions suggests that there were multipe refugia or in situ survival of S. davidii in the Himalayan-Hengduan Mountain region. Fixation of chlorotypes in the northeastern region and near fixation in the southeastern region suggest a recent colonization of these areas. We further found that this species underwent past range expansion around 37-303 thousand years ago (kya). The southeastern populations likely experienced a demographic expansion via unidirectional gene flow along rivers, while northeastern populations underwent a more northward expansion, both from initial populations (s) (21, 22, 23) preserved on eastern refugia (Jinshajiang). This process might have been accompanied with a series of founder effects or bottlenecks making populations genetically impoverished. 3. Phylogeographic analysisbased on nuclear sequence，We sequenced the nuclear (ncpGS) region in all populations sampled, recovering 23 nuclear haplotypes. Compared to cpDNA, both NST (0.470) and GST (0.338) were relatively lower, but NST was also significantly larger than GST. 37.10% of the total variation was distributed among regions which was much lower than that shown by chlorotypes. Thus, more extensive distribution of nuclear haplotypes was exhibited across the geographical range instead of the strong population subdivision observed in chlorotypes. Similarly to the chloroplast data, we found that genetic differentiation of nDNA was positively correlated with the geographical distance, but the increase in the geographical distance between populations did not increase the genetic differentiation of nDNA as rapidly as that of cpDNA. These contrasting levels between the chloroplast and nuclear genomes of S. davidii are likely due to limited gene flow of cpDNA by seeds vs. the extensive gene flow of nDNA by wind-mediated pollen in the population history. We also determined from nuclear markers that haplotype diversity was reduced in the southeastern and northeastern regions due to the loss of rare haplotypes in western region. This reduction of gene diversity is also a signature of founder events or recent bottleneck during post-glacial colonization. However, nuclear diversity within populations remains high. This provides evidence that regionally pollen flow might be sufficiently high to blur the genetic identity of founder populations over a reasonably large spatial scale.3. Relationships among three varieties，The phylogenetic analysis identified two phylogroups of chlorotypes, corresponding to S. davidii var. davidii and var. chuansinesis. The former was distinguished by the abscence of predonminant nuclear haplotype H1 of the latter. The monophyletic group of chlorotypes in var. davidii and var. liangshanesis showed their relatively close relationship. And their genetic divergence from the third variety appears to be relative to their slight morphological difference in leaf size and the divergent environmental niche spaces they occupy. Thus, the observed differences in morphological characters between var. chuansinesis and other two varieties can be explained by the seed dispersal limitation illustrated above (as inferred by geographical separation) and by environmental heterogeneity (as inferred by precipitation or elevation) or by a combination of both. After all, the geological changes, drainage reorganization, and floristic differences following the Himalayan uplift have been suggested to affect the genetic structure of S. davidii. These results provide new insights into the phylogeographic pattern of plants in China. In addition, the unique population genetic structure found in S. davidii has provided important insights into the evolutionary history of this species. The genetic profile uncovered in this study is also critical for its conservation management. Our study has uncovered the existence of at least two ‘evolutionary significant units’ independent units within S. davidii, corresponding to var. davidii from eastern region and var. chuansinensis from western region. The conservation efforts should first focus on most western populations and on the southeastern ones exhibiting high levels of genetic diversity, while the genetically homogeneous northeastern populations located in the degraded Loess Plateau should require much greater conservation efforts.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=%25E6%2596%25B0%25E7%25BB%2584%25E5%2590%2588&&fq=dc.project.title_filter%3ASophora%5C+davidii%5C+%5C%28Franch.%5C%29%5C+Skeels%5C+is%5C+an%5C+endemic%5C+species%5C+to%5C+China%2C%5C+and%5C+widely%5C+distributed%5C+in%5C+the%5C+dry%5C+valleys%5C+of%5C+the%5C+Himalayan%5C-Hengduan%5C+Mountain%5C+Systems%2C%5C+the%5C+Yungui%5C+Plateau%2C%5C+the%5C+Qinling%5C+Mountain%2C%5C+the%5C+Loess%5C+Plateau%5C+and%5C+other%5C+places%5C+of%5C+China.%5C+Previous%5C+studies%5C+of%5C+plant%5C+phylogeography%5C+have%5C+focused%5C+mainly%5C+on%5C+some%5C+taxa%5C+from%5C+the%5C+mountainous%5C+areas%5C+of%5C+China%2C%5C+relatively%5C+few%5C+studies%5C+have%5C+been%5C+conducted%5C+on%5C+plant%5C+taxa%5C+from%5C+the%5C+river%5C+valleys.%5C+The%5C+population%5C+dynamics%5C+and%5C+evolutionary%5C+history%5C+of%5C+species%5C+in%5C+such%5C+habitat%5C+remain%5C+less%5C+unknown%2C%5C+including%5C+the%5C+factors%5C+affecting%5C+the%5C+population%5C+genetic%5C+structure%5C+and%5C+its%5C+potential%5C+refugia%5C+in%5C+glaciation.%5C+In%5C+this%5C+study%2C%5C+we%5C+first%5C+determine%5C+the%5C+chromosome%5C+number%2C%5C+ploidy%5C+and%5C+karyotype%5C+of%5C+most%5C+populations%5C+we%5C+sampled.%5C+Then%2C%5C+based%5C+on%5C+sequence%5C+data%5C+from%5C+two%5C+maternally%5C+inherited%5C+cpDNA%5C+and%5C+one%5C+biparentally%5C+inherited%5C+nuclear%5C+DNA%5C+fragments%2C%5C+our%5C+study%5C+revealed%5C+the%5C+genetic%5C+diversity%5C+and%5C+population%5C+genetic%5C+structure%5C+of%5C+S.%5C+davidii%5C+and%5C+factors%5C+affecting%5C+them.%5C+The%5C+demographic%5C+history%5C+and%5C+potential%5C+refugia%5C+of%5C+this%5C+speices%5C+were%5C+investigated%5C+and%5C+the%5C+genetic%5C+relationship%5C+among%5C+three%5C+varieties%5C+was%5C+also%5C+clarified.%5C+The%5C+main%5C+results%5C+are%5C+summarized%5C+as%5C+follows%5C%3A1.%5C+Cytogeography%EF%BC%8CThe%5C+chromosome%5C+number%5C+and%5C+karyotypes%5C+of%5C+14%5C+S.%5C+davidii%5C+populations%5C+have%5C+been%5C+studied.%5C+The%5C+results%5C+showed%5C+that%5C+the%5C+choromosome%5C+number%5C+of%5C+all%5C+the%5C+populations%5C+is%5C+2n%5C+%3D%5C+18.%5C+The%5C+interphase%5C+nuclei%5C+and%5C+prophase%5C+chromosomes%5C+of%5C+the%5C+species%5C+were%5C+found%5C+to%5C+be%5C+of%5C+the%5C+complex%5C+chromosome%5C+type%5C+and%5C+interstitial%5C+type.%5C+The%5C+results%5C+of%5C+karyotype%5C+analysis%5C+showed%5C+that%5C+7%5C+of%5C+14%5C+materials%5C+has%5C+satellites%2C%5C+and%5C+the%5C+number%5C+and%5C+position%5C+of%5C+satellites%5C+differ%5C+among%5C+populations%2C%5C+and%5C+thus%5C+revealed%5C+a%5C+series%5C+of%5C+diversified%5C+karyotypes.%5C+With%5C+most%5C+populations%5C+being%5C+of%5C+ploidy%2C%5C+cytogenetical%5C+divergence%5C+within%5C+the%5C+species%5C+lied%5C+mainly%5C+in%5C+chromosome%5C+size%5C+and%5C+structure.%5C+The%5C+fact%5C+that%5C+polyploidization%5C+did%5C+not%5C+occur%5C+very%5C+often%5C+for%5C+variations%5C+in%5C+Southwest%5C+China%5C+was%5C+against%5C+viewpoint%5C+that%5C+polyploidization%5C+level%5C+in%5C+this%5C+area%5C+is%5C+higher%5C+than%5C+that%5C+of%5C+other%5C+distribution%5C+areas%5C+due%5C+to%5C+the%5C+elevation%5C+of%5C+mountains%5C+and%5C+plateau.%5C+2.%5C+Phylogeographic%5C+analysisbased%5C+on%5C+chloroplast%5C+sequence%EF%BC%8CWe%5C+sequenced%5C+two%5C+cpDNA%5C+fragments%5C+rpl32%5C-trnL%5C%28UAG%5C%29intergenic%5C+spacer%5C+and%5C+trnH%5C-psbA%5C+spacer%5C+in%5C+40%5C+populations%5C+sampled%2C%5C+recovering%5C+22%5C+chlorotypes.%5C+The%5C+average%5C+with%5C-in%5C+population%5C+diversity%5C+%5C%28hS%5C+%3D%5C+0.171%5C%29%5C+was%5C+much%5C+lower%5C+than%5C+total%5C+genetic%5C+diversity%5C+%5C%28hT%5C+%3D%5C+0.857%5C%29.%5C+Population%5C+differentiation%5C+was%5C+high%5C+%5C%28NST%5C+%3D%5C+0.924%2C%5C+GST%5C+%3D%5C+0.801%5C%29%5C+indicating%5C+low%5C+levels%5C+of%5C+seed%5C-based%5C+gene%5C+flow%5C+and%5C+significant%5C+phylogeographical%5C+stucture%5C+%5C%28NST%5C+%3E%5C+GST%2C%5C+P%5C+%3C%5C+0.05%5C%29%5C+were%5C+exhibited%5C+by%5C+this%5C+species.%5C+The%5C+SAMOVA%5C+revealed%5C+seven%5C+diverging%5C+groups%5C+of%5C+related%5C+chlorotypes%2C%5C+six%5C+of%5C+them%5C+had%5C+distinct%5C+nonoverlapping%5C+geographical%5C+ranges%5C%3A%5C+one%5C+in%5C+the%5C+northeast%5C+comprising%5C+10%5C+populations%2C%5C+a%5C+second%5C+with%5C+a%5C+southeast%5C+distribution%5C+comprising%5C+22%5C+populations%2C%5C+and%5C+the%5C+remaning%5C+four%5C+groups%5C+comprising%5C+15%5C+populations%5C+located%5C+in%5C+the%5C+west%5C+part%5C+of%5C+the%5C+species%E2%80%99%5C+range%5C+along%5C+different%5C+river%5C+valleys.%5C+The%5C+genetic%5C+clustering%5C+of%5C+populations%5C+into%5C+three%5C+regions%5C+was%5C+also%5C+supported%5C+by%5C+analysis%5C+of%5C+molecular%5C+variance%2C%5C+which%5C+showed%5C+that%5C+most%5C+genetic%5C+variation%5C+%5C%2882.43%25%5C%29%5C+was%5C+found%5C+among%5C+these%5C+three%5C+regions.%5C+Two%5C+clusters%5C+were%5C+distinguished%5C+by%5C+both%5C+phylogenetic%5C+analysis%5C+and%5C+genealogical%5C+analysis%5C+of%5C+chlorotypes%2C%5C+one%5C+consisting%5C+of%5C+chlorotypes%5C+from%5C+the%5C+western%5C+region%5C+and%5C+the%5C+second%5C+consisting%5C+of%5C+those%5C+from%5C+the%5C+eastern%5C+region.%5C+Significant%5C+genetic%5C+differences%5C+between%5C+the%5C+two%5C+regions%5C+might%5C+be%5C+attributed%5C+to%5C+vicariance%5C+and%5C+restricted%5C+gene%5C+flow%2C%5C+and%5C+this%5C+vicariance%5C+could%5C+be%5C+explained%5C+by%5C+the%5C+physical%5C+environmental%5C+heterogeneity%5C+on%5C+each%5C+side%5C+of%5C+the%5C+Tanaka%5C-Kaiyong%5C+Line.%5C+Following%5C+the%5C+uplift%5C+of%5C+the%5C+Tibetan%5C+Plateau%2C%5C+the%5C+reorganization%5C+of%5C+the%5C+major%5C+river%5C+drainages%5C+was%5C+primarily%5C+caused%5C+by%5C+river%5C+separation%5C+and%5C+capture%5C+events.%5C+These%5C+historical%5C+events%5C+could%5C+change%5C+the%5C+distribution%5C+of%5C+S.%5C+davidii%5C+from%5C+fragmented%5C+to%5C+continuous%5C+%5C%28Upper%5C%2FLower%5C+Jinshajiang%5C+and%5C+Yalongjiang%5C%2FDaduhe%5C%29%2C%5C+and%5C+from%5C+continuous%5C+to%5C+fragmented%5C+%5C%28Nujiang%5C+and%5C+Jinshajiang%5C%2FHonghe%5C%29.%5C+However%2C%5C+spatial%5C+and%5C+temporal%5C+patterns%5C+of%5C+phylogeographic%5C+divergence%5C+are%5C+strongly%5C+associated%5C+with%5C+historical%5C+disjunction%5C+rather%5C+than%5C+modern%5C+drainage%5C+connections.%5C+Moreover%2C%5C+the%5C+following%5C+north%5C-south%5C+split%5C+in%5C+the%5C+eastern%5C+region%5C+and%5C+effective%5C+isolation%5C+with%5C+their%5C+genetic%5C+diversity%5C+were%5C+essentially%5C+modelled%5C+by%5C+genetic%5C+drift.%5C+The%5C+higher%5C+chlorotype%5C+richness%5C+and%5C+genetic%5C+divergence%5C+for%5C+populations%5C+in%5C+western%5C+region%5C+compared%5C+with%5C+other%5C+two%5C+regions%5C+suggests%5C+that%5C+there%5C+were%5C+multipe%5C+refugia%5C+or%5C+in%5C+situ%5C+survival%5C+of%5C+S.%5C+davidii%5C+in%5C+the%5C+Himalayan%5C-Hengduan%5C+Mountain%5C+region.%5C+Fixation%5C+of%5C+chlorotypes%5C+in%5C+the%5C+northeastern%5C+region%5C+and%5C+near%5C+fixation%5C+in%5C+the%5C+southeastern%5C+region%5C+suggest%5C+a%5C+recent%5C+colonization%5C+of%5C+these%5C+areas.%5C+We%5C+further%5C+found%5C+that%5C+this%5C+species%5C+underwent%5C+past%5C+range%5C+expansion%5C+around%5C+37%5C-303%5C+thousand%5C+years%5C+ago%5C+%5C%28kya%5C%29.%5C+The%5C+southeastern%5C+populations%5C+likely%5C+experienced%5C+a%5C+demographic%5C+expansion%5C+via%5C+unidirectional%5C+gene%5C+flow%5C+along%5C+rivers%2C%5C+while%5C+northeastern%5C+populations%5C+underwent%5C+a%5C+more%5C+northward%5C+expansion%2C%5C+both%5C+from%5C+initial%5C+populations%5C+%5C%28s%5C%29%5C+%5C%2821%2C%5C+22%2C%5C+23%5C%29%5C+preserved%5C+on%5C+eastern%5C+refugia%5C+%5C%28Jinshajiang%5C%29.%5C+This%5C+process%5C+might%5C+have%5C+been%5C+accompanied%5C+with%5C+a%5C+series%5C+of%5C+founder%5C+effects%5C+or%5C+bottlenecks%5C+making%5C+populations%5C+genetically%5C+impoverished.%5C+3.%5C+Phylogeographic%5C+analysisbased%5C+on%5C+nuclear%5C+sequence%EF%BC%8CWe%5C+sequenced%5C+the%5C+nuclear%5C+%5C%28ncpGS%5C%29%5C+region%5C+in%5C+all%5C+populations%5C+sampled%2C%5C+recovering%5C+23%5C+nuclear%5C+haplotypes.%5C+Compared%5C+to%5C+cpDNA%2C%5C+both%5C+NST%5C+%5C%280.470%5C%29%5C+and%5C+GST%5C+%5C%280.338%5C%29%5C+were%5C+relatively%5C+lower%2C%5C+but%5C+NST%5C+was%5C+also%5C+significantly%5C+larger%5C+than%5C+GST.%5C+37.10%25%5C+of%5C+the%5C+total%5C+variation%5C+was%5C+distributed%5C+among%5C+regions%5C+which%5C+was%5C+much%5C+lower%5C+than%5C+that%5C+shown%5C+by%5C+chlorotypes.%5C+Thus%2C%5C+more%5C+extensive%5C+distribution%5C+of%5C+nuclear%5C+haplotypes%5C+was%5C+exhibited%5C+across%5C+the%5C+geographical%5C+range%5C+instead%5C+of%5C+the%5C+strong%5C+population%5C+subdivision%5C+observed%5C+in%5C+chlorotypes.%5C+Similarly%5C+to%5C+the%5C+chloroplast%5C+data%2C%5C+we%5C+found%5C+that%5C+genetic%5C+differentiation%5C+of%5C+nDNA%5C+was%5C+positively%5C+correlated%5C+with%5C+the%5C+geographical%5C+distance%2C%5C+but%5C+the%5C+increase%5C+in%5C+the%5C+geographical%5C+distance%5C+between%5C+populations%5C+did%5C+not%5C+increase%5C+the%5C+genetic%5C+differentiation%5C+of%5C+nDNA%5C+as%5C+rapidly%5C+as%5C+that%5C+of%5C+cpDNA.%5C+These%5C+contrasting%5C+levels%5C+between%5C+the%5C+chloroplast%5C+and%5C+nuclear%5C+genomes%5C+of%5C+S.%5C+davidii%5C+are%5C+likely%5C+due%5C+to%5C+limited%5C+gene%5C+flow%5C+of%5C+cpDNA%5C+by%5C+seeds%5C+vs.%5C+the%5C+extensive%5C+gene%5C+flow%5C+of%5C+nDNA%5C+by%5C+wind%5C-mediated%5C+pollen%5C+in%5C+the%5C+population%5C+history.%5C+We%5C+also%5C+determined%5C+from%5C+nuclear%5C+markers%5C+that%5C+haplotype%5C+diversity%5C+was%5C+reduced%5C+in%5C+the%5C+southeastern%5C+and%5C+northeastern%5C+regions%5C+due%5C+to%5C+the%5C+loss%5C+of%5C+rare%5C+haplotypes%5C+in%5C+western%5C+region.%5C+This%5C+reduction%5C+of%5C+gene%5C+diversity%5C+is%5C+also%5C+a%5C+signature%5C+of%5C+founder%5C+events%5C+or%5C+recent%5C+bottleneck%5C+during%5C+post%5C-glacial%5C+colonization.%5C+However%2C%5C+nuclear%5C+diversity%5C+within%5C+populations%5C+remains%5C+high.%5C+This%5C+provides%5C+evidence%5C+that%5C+regionally%5C+pollen%5C+flow%5C+might%5C+be%5C+sufficiently%5C+high%5C+to%5C+blur%5C+the%5C+genetic%5C+identity%5C+of%5C+founder%5C+populations%5C+over%5C+a%5C+reasonably%5C+large%5C+spatial%5C+scale.3.%5C+Relationships%5C+among%5C+three%5C+varieties%EF%BC%8CThe%5C+phylogenetic%5C+analysis%5C+identified%5C+two%5C+phylogroups%5C+of%5C+chlorotypes%2C%5C+corresponding%5C+to%5C+S.%5C+davidii%5C+var.%5C+davidii%5C+and%5C+var.%5C+chuansinesis.%5C+The%5C+former%5C+was%5C+distinguished%5C+by%5C+the%5C+abscence%5C+of%5C+predonminant%5C+nuclear%5C+haplotype%5C+H1%5C+of%5C+the%5C+latter.%5C+The%5C+monophyletic%5C+group%5C+of%5C+chlorotypes%5C+in%5C+var.%5C+davidii%5C+and%5C+var.%5C+liangshanesis%5C+showed%5C+their%5C+relatively%5C+close%5C+relationship.%5C+And%5C+their%5C+genetic%5C+divergence%5C+from%5C+the%5C+third%5C+variety%5C+appears%5C+to%5C+be%5C+relative%5C+to%5C+their%5C+slight%5C+morphological%5C+difference%5C+in%5C+leaf%5C+size%5C+and%5C+the%5C+divergent%5C+environmental%5C+niche%5C+spaces%5C+they%5C+occupy.%5C+Thus%2C%5C+the%5C+observed%5C+differences%5C+in%5C+morphological%5C+characters%5C+between%5C+var.%5C+chuansinesis%5C+and%5C+other%5C+two%5C+varieties%5C+can%5C+be%5C+explained%5C+by%5C+the%5C+seed%5C+dispersal%5C+limitation%5C+illustrated%5C+above%5C+%5C%28as%5C+inferred%5C+by%5C+geographical%5C+separation%5C%29%5C+and%5C+by%5C+environmental%5C+heterogeneity%5C+%5C%28as%5C+inferred%5C+by%5C+precipitation%5C+or%5C+elevation%5C%29%5C+or%5C+by%5C+a%5C+combination%5C+of%5C+both.%5C+After%5C+all%2C%5C+the%5C+geological%5C+changes%2C%5C+drainage%5C+reorganization%2C%5C+and%5C+floristic%5C+differences%5C+following%5C+the%5C+Himalayan%5C+uplift%5C+have%5C+been%5C+suggested%5C+to%5C+affect%5C+the%5C+genetic%5C+structure%5C+of%5C+S.%5C+davidii.%5C+These%5C+results%5C+provide%5C+new%5C+insights%5C+into%5C+the%5C+phylogeographic%5C+pattern%5C+of%5C+plants%5C+in%5C+China.%5C+In%5C+addition%2C%5C+the%5C+unique%5C+population%5C+genetic%5C+structure%5C+found%5C+in%5C+S.%5C+davidii%5C+has%5C+provided%5C+important%5C+insights%5C+into%5C+the%5C+evolutionary%5C+history%5C+of%5C+this%5C+species.%5C+The%5C+genetic%5C+profile%5C+uncovered%5C+in%5C+this%5C+study%5C+is%5C+also%5C+critical%5C+for%5C+its%5C+conservation%5C+management.%5C+Our%5C+study%5C+has%5C+uncovered%5C+the%5C+existence%5C+of%5C+at%5C+least%5C+two%5C+%E2%80%98evolutionary%5C+significant%5C+units%E2%80%99%5C+independent%5C+units%5C+within%5C+S.%5C+davidii%2C%5C+corresponding%5C+to%5C+var.%5C+davidii%5C+from%5C+eastern%5C+region%5C+and%5C+var.%5C+chuansinensis%5C+from%5C+western%5C+region.%5C+The%5C+conservation%5C+efforts%5C+should%5C+first%5C+focus%5C+on%5C+most%5C+western%5C+populations%5C+and%5C+on%5C+the%5C+southeastern%5C+ones%5C+exhibiting%5C+high%5C+levels%5C+of%5C+genetic%5C+diversity%2C%5C+while%5C+the%5C+genetically%5C+homogeneous%5C+northeastern%5C+populations%5C+located%5C+in%5C+the%5C+degraded%5C+Loess%5C+Plateau%5C+should%5C+require%5C+much%5C+greater%5C+conservation%5C+efforts."},{"jsname":"The Taxus wallichiana complex represents an old relict conifer lineage that survived through the Tertiary. It is currently distributed in the mountain forests in South and Southwest China south of the Qinling Mountains. In the present study, we explored phylogeography of the complex by using two chloroplast DNA regions, one nuclear ribosomal DNA spacer region and eight microsatellite (SSR) loci. The main conclusions can be summarized as follows:1. Phylogeographic pattern based on chloroplast haplotypes，There were 11 cpDNA haplotypes identified in the T. wallichiana complex The complex showed a high level of genetic diversity and obvious genetic differentiation. The 44 sampled populations showed obvious genetic structure, which could be divided into five groups, namely the Huanan group, the Daba group, the Emei group, the Yunnan group and the Qinling group. There was extremely high genetic differentiation among groups, but not significant within group. The divergence times of the five lineages, estimated using average mutation rates of trnL-trnF, fell in the Pliocene. 2. Phylogeographic patterns based on ITS sequences，These included 38 unique ‘haplotypes’ based on ITS data. Their analysis showed that the T. wallichiana complex possessed a high genetic diversity. These populations could be divided into four groups, namely the Huanan group, the Daba/Emei group, the Yunnan group and the Qinling group. Based on all results, it appears that the major lineages constituting the T. wallichiana complex have arisen before Quaternary glaciation cycles, and may have survived isolated in different refugia. During interglacial periods some lineages appear to have come in contact and hybridizedbut other lineages merged forming populations with mixed haplotypes without signs of hybridization. The present-day phylogeographical distribution pattern of the T. wallichiana complex might thus be the result of repeated expansion / contractions of populations during interglacial / glacial cycles.3. Population genetic analysis using microsatellite (SSR) markers，Eight SSR loci were used for population genetic analysis on the T. wallichiana complex. A lower level of genetic diversity at the population level and high genetic differentiation among population was detected. The results of structure analysis were similar to those on the ITS data, dividing the populations into four groups (lineages). According to the results here, it was deduced that each of the 4 lineages of the T. wallichiana complex may possessed respective glacial refugia, and some lineages (such as the Qinling and Huanan lineage) might have survived in multiple refugia in the Quaternay glaciations. The present distribution pattern of this complex was likely influenced by the uplift of the QTP and Quaternary glaciation.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=%25E6%2596%25B0%25E7%25BB%2584%25E5%2590%2588&&fq=dc.project.title_filter%3AThe%5C+Taxus%5C+wallichiana%5C+complex%5C+represents%5C+an%5C+old%5C+relict%5C+conifer%5C+lineage%5C+that%5C+survived%5C+through%5C+the%5C+Tertiary.%5C+It%5C+is%5C+currently%5C+distributed%5C+in%5C+the%5C+mountain%5C+forests%5C+in%5C+South%5C+and%5C+Southwest%5C+China%5C+south%5C+of%5C+the%5C+Qinling%5C+Mountains.%C2%A0In%5C+the%5C+present%5C+study%2C%5C+we%5C+explored%5C+phylogeography%5C+of%5C+the%5C+complex%5C+by%5C+using%5C+two%5C+chloroplast%5C+DNA%5C+regions%2C%5C+one%5C+nuclear%5C+ribosomal%5C+DNA%5C+spacer%5C+region%5C+and%5C+eight%5C+microsatellite%5C+%5C%28SSR%5C%29%5C+loci.%5C+The%5C+main%5C+conclusions%5C+can%5C+be%5C+summarized%5C+as%5C+follows%5C%3A1.%5C+Phylogeographic%5C+pattern%5C+based%5C+on%5C+chloroplast%5C+haplotypes%EF%BC%8CThere%5C+were%5C+11%5C+cpDNA%5C+haplotypes%5C+identified%5C+in%5C+the%5C+T.%5C+wallichiana%5C+complex%5C+The%5C+complex%5C+showed%5C+a%5C+high%5C+level%5C+of%5C+genetic%5C+diversity%5C+and%5C+obvious%5C+genetic%5C+differentiation.%5C+The%5C+44%5C+sampled%5C+populations%5C+showed%5C+obvious%5C+genetic%5C+structure%2C%5C+which%5C+could%5C+be%5C+divided%5C+into%5C+five%5C+groups%2C%5C+namely%5C+the%5C+Huanan%5C+group%2C%5C+the%5C+Daba%5C+group%2C%5C+the%5C+Emei%5C+group%2C%5C+the%5C+Yunnan%5C+group%5C+and%5C+the%5C+Qinling%5C+group.%5C+There%5C+was%5C+extremely%5C+high%5C+genetic%5C+differentiation%5C+among%5C+groups%2C%5C+but%5C+not%5C+significant%5C+within%5C+group.%5C+The%5C+divergence%5C+times%5C+of%5C+the%5C+five%5C+lineages%2C%5C+estimated%5C+using%5C+average%5C+mutation%5C+rates%5C+of%5C+trnL%5C-trnF%2C%5C+fell%5C+in%5C+the%5C+Pliocene.%C2%A02.%5C+Phylogeographic%5C+patterns%5C+based%5C+on%5C+ITS%5C+sequences%EF%BC%8CThese%5C+included%5C+38%5C+unique%5C+%E2%80%98haplotypes%E2%80%99%5C+based%5C+on%5C+ITS%5C+data.%5C+Their%5C+analysis%5C+showed%5C+that%5C+the%5C+T.%5C+wallichiana%5C+complex%5C+possessed%5C+a%5C+high%5C+genetic%5C+diversity.%C2%A0These%5C+populations%5C+could%5C+be%5C+divided%5C+into%5C+four%5C+groups%2C%5C+namely%5C+the%5C+Huanan%5C+group%2C%5C+the%5C+Daba%5C%2FEmei%5C+group%2C%5C+the%5C+Yunnan%5C+group%5C+and%5C+the%5C+Qinling%5C+group.%5C+Based%5C+on%5C+all%5C+results%2C%5C+it%5C+appears%5C+that%5C+the%5C+major%5C+lineages%5C+constituting%5C+the%5C+T.%5C+wallichiana%5C+complex%5C+have%5C+arisen%5C+before%5C+Quaternary%5C+glaciation%5C+cycles%2C%5C+and%5C+may%5C+have%5C+survived%5C+isolated%5C+in%5C+different%5C+refugia.%5C+During%5C+interglacial%5C+periods%5C+some%5C+lineages%5C+appear%5C+to%5C+have%5C+come%5C+in%5C+contact%5C+and%5C+hybridizedbut%5C+other%5C+lineages%5C+merged%5C+forming%5C+populations%5C+with%5C+mixed%5C+haplotypes%5C+without%5C+signs%5C+of%5C+hybridization.%5C+The%5C+present%5C-day%5C+phylogeographical%5C+distribution%5C+pattern%5C+of%5C+the%5C+T.%5C+wallichiana%5C+complex%5C+might%5C+thus%5C+be%5C+the%5C+result%5C+of%5C+repeated%5C+expansion%5C+%5C%2F%5C+contractions%5C+of%5C+populations%5C+during%5C+interglacial%5C+%5C%2F%5C+glacial%5C+cycles.3.%5C+Population%5C+genetic%5C+analysis%5C+using%5C+microsatellite%5C+%5C%28SSR%5C%29%5C+markers%EF%BC%8CEight%5C+SSR%5C+loci%5C+were%5C+used%5C+for%5C+population%5C+genetic%5C+analysis%5C+on%5C+the%5C+T.%5C+wallichiana%5C+complex.%5C+A%5C+lower%5C+level%5C+of%5C+genetic%5C+diversity%5C+at%5C+the%5C+population%5C+level%5C+and%5C+high%5C+genetic%5C+differentiation%5C+among%5C+population%5C+was%5C+detected.%5C+The%5C+results%5C+of%5C+structure%5C+analysis%5C+were%5C+similar%5C+to%5C+those%5C+on%5C+the%5C+ITS%5C+data%2C%5C+dividing%5C+the%5C+populations%5C+into%5C+four%5C+groups%5C+%5C%28lineages%5C%29.%C2%A0According%5C+to%5C+the%5C+results%5C+here%2C%5C+it%5C+was%5C+deduced%5C+that%5C+each%5C+of%5C+the%5C+4%5C+lineages%5C+of%5C+the%5C+T.%5C+wallichiana%5C+complex%5C+may%5C+possessed%5C+respective%5C+glacial%5C+refugia%2C%5C+and%5C+some%5C+lineages%5C+%5C%28such%5C+as%5C+the%5C+Qinling%5C+and%5C+Huanan%5C+lineage%5C%29%5C+might%5C+have%5C+survived%5C+in%5C+multiple%5C+refugia%5C+in%5C+the%5C+Quaternay%5C+glaciations.%5C+The%5C+present%5C+distribution%5C+pattern%5C+of%5C+this%5C+complex%5C+was%5C+likely%5C+influenced%5C+by%5C+the%5C+uplift%5C+of%5C+the%5C+QTP%5C+and%5C+Quaternary%5C+glaciation."},{"jsname":"The temperate woody bamboos are a morphologically diverse group with a complicated taxonomy. The Arundinaria group has an East Asia-North America disjunct distribution, which is one of those with complex taxonomy in the temperate woody bamboos. In this study, the phylogeny of the temperate woody bamboos was reconstructed based on eight non-coding regions of the chloroplast genome and nuclear gene GBSSI using large sample set (124 species in 24 genera) with an emphasis on the Arundinaria group. The monophyly of the temperate woody bamboos was resolved in all phylogenies. Ten major lineages were obtained in the chloroplast phylogeny with unresolved relationships among them; the recovered phylogeny is strongly incongruent with the classifications based on morphology at both subtribal and generic ranks; some subclades that are related to the geographic distribution were obtained in those lineages. Five lineages in the GBSSI gene phylogeny were recovered as the same in the chloroplast phylogeny, and the other lineages were incongruent with chloroplast phylogeny in some ways. The reticulate evolution caused by hybridization, introgression and lineage sorting may be an explanation for the molecular phylogenetic incongruence. Based on the facts of diverse morphology, broad distribution and molecular phylogeny, we inferred that the major clades and species within most of the clades of the temperate woody bamboos were originated during several rapid adaptive radiations. Ten putative hybrids were discussed based on molecular phylogenies, morphology and distribution. The micromorphology of the leaf epidermis under SEM (scanning electron microscope) was observed and divided into nine types; the micromorphology can provide some evidence for the bamboo taxonomy and inference of putative hybrids. Additionally, taxonomic revisions were presented for some species based on field observation and herbarium work.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=%25E6%2596%25B0%25E7%25BB%2584%25E5%2590%2588&&fq=dc.project.title_filter%3AThe%5C+temperate%5C+woody%5C+bamboos%5C+are%5C+a%5C+morphologically%5C+diverse%5C+group%5C+with%5C+a%5C+complicated%5C+taxonomy.%5C+The%5C+Arundinaria%5C+group%5C+has%5C+an%5C+East%5C+Asia%5C-North%5C+America%5C+disjunct%5C+distribution%2C%5C+which%5C+is%5C+one%5C+of%5C+those%5C+with%5C+complex%5C+taxonomy%5C+in%5C+the%5C+temperate%5C+woody%5C+bamboos.%5C+In%5C+this%5C+study%2C%5C+the%5C+phylogeny%5C+of%5C+the%5C+temperate%5C+woody%5C+bamboos%5C+was%5C+reconstructed%5C+based%5C+on%5C+eight%5C+non%5C-coding%5C+regions%5C+of%5C+the%5C+chloroplast%5C+genome%5C+and%5C+nuclear%5C+gene%5C+GBSSI%5C+using%5C+large%5C+sample%5C+set%5C+%5C%28124%5C+species%5C+in%5C+24%5C+genera%5C%29%5C+with%5C+an%5C+emphasis%5C+on%5C+the%5C+Arundinaria%5C+group.%5C+The%5C+monophyly%5C+of%5C+the%5C+temperate%5C+woody%5C+bamboos%5C+was%5C+resolved%5C+in%5C+all%5C+phylogenies.%5C+Ten%5C+major%5C+lineages%5C+were%5C+obtained%5C+in%5C+the%5C+chloroplast%5C+phylogeny%5C+with%5C+unresolved%5C+relationships%5C+among%5C+them%5C%3B%5C+the%5C+recovered%5C+phylogeny%5C+is%5C+strongly%5C+incongruent%5C+with%5C+the%5C+classifications%5C+based%5C+on%5C+morphology%5C+at%5C+both%5C+subtribal%5C+and%5C+generic%5C+ranks%5C%3B%5C+some%5C+subclades%5C+that%5C+are%5C+related%5C+to%5C+the%5C+geographic%5C+distribution%5C+were%5C+obtained%5C+in%5C+those%5C+lineages.%5C+Five%5C+lineages%5C+in%5C+the%5C+GBSSI%5C+gene%5C+phylogeny%5C+were%5C+recovered%5C+as%5C+the%5C+same%5C+in%5C+the%5C+chloroplast%5C+phylogeny%2C%5C+and%5C+the%5C+other%5C+lineages%5C+were%5C+incongruent%5C+with%5C+chloroplast%5C+phylogeny%5C+in%5C+some%5C+ways.%5C+The%5C+reticulate%5C+evolution%5C+caused%5C+by%5C+hybridization%2C%5C+introgression%5C+and%5C+lineage%5C+sorting%5C+may%5C+be%5C+an%5C+explanation%5C+for%5C+the%5C+molecular%5C+phylogenetic%5C+incongruence.%5C+Based%5C+on%5C+the%5C+facts%5C+of%5C+diverse%5C+morphology%2C%5C+broad%5C+distribution%5C+and%5C+molecular%5C+phylogeny%2C%5C+we%5C+inferred%5C+that%5C+the%5C+major%5C+clades%5C+and%5C+species%5C+within%5C+most%5C+of%5C+the%5C+clades%5C+of%5C+the%5C+temperate%5C+woody%5C+bamboos%5C+were%5C+originated%5C+during%5C+several%5C+rapid%5C+adaptive%5C+radiations.%5C+Ten%5C+putative%5C+hybrids%5C+were%5C+discussed%5C+based%5C+on%5C+molecular%5C+phylogenies%2C%5C+morphology%5C+and%5C+distribution.%5C+The%5C+micromorphology%5C+of%5C+the%5C+leaf%5C+epidermis%5C+under%5C+SEM%5C+%5C%28scanning%5C+electron%5C+microscope%5C%29%5C+was%5C+observed%5C+and%5C+divided%5C+into%5C+nine%5C+types%5C%3B%5C+the%5C+micromorphology%5C+can%5C+provide%5C+some%5C+evidence%5C+for%5C+the%5C+bamboo%5C+taxonomy%5C+and%5C+inference%5C+of%5C+putative%5C+hybrids.%5C+Additionally%2C%5C+taxonomic%5C+revisions%5C+were%5C+presented%5C+for%5C+some%5C+species%5C+based%5C+on%5C+field%5C+observation%5C+and%5C+herbarium%5C+work."},{"jsname":"This thesis deals with the research work on the chemical constituents of Camellia taliensis, Camellia pachyandra, Camellia oleifera, Metapanax delavayi , Pu-er tea (Camellia sinensis var. assamica) and one of the dominant microorganisms in the post-fermentation of Pu-er tea, Aspergillus japonicus var. japonicus through the systematic phytochemical methods. By the modern techniques of chromatography, spectroscopy along with chemical degradation methods, 107 compounds were isolated and identified by MS, 1D and 2D NMR spectra along with other spectroscopic method along with chemical degradation. The compounds include hydrolysable tannins, flavan-3ols, flavonoid glycosides, triterpene glycosides, simple phenolics and so on, most of which were evaluated by antioxidant or anti-viral activities. Meantime, the HPLC analytical methods were applied to compare the chemical constituents of C. taliensis and C. pachyandra with with those of the cultivated tea, C. sinensis var. assamica. Above all, the detection methods were established for the analysis of tea polyphenols, tea polysaccharides, caffeine and the main polyphenolic constituents in tea. And finally, the progress of the research work on Pu-er tea was reviewed.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=%25E6%2596%25B0%25E7%25BB%2584%25E5%2590%2588&&fq=dc.project.title_filter%3AThis%5C+thesis%5C+deals%5C+with%5C+the%5C+research%5C+work%5C+on%5C+the%5C+chemical%5C+constituents%5C+of%5C+Camellia%5C+taliensis%2C%5C+Camellia%5C+pachyandra%2C%5C+Camellia%5C+oleifera%2C%5C+Metapanax%5C+delavayi%5C+%2C%5C+Pu%5C-er%5C+tea%5C+%5C%28Camellia%5C+sinensis%5C+var.%5C+assamica%5C%29%5C+and%5C+one%5C+of%5C+the%5C+dominant%5C+microorganisms%5C+in%5C+the%5C+post%5C-fermentation%5C+of%5C+Pu%5C-er%5C+tea%2C%5C+Aspergillus%5C+japonicus%5C+var.%5C+japonicus%5C+through%5C+the%5C+systematic%5C+phytochemical%5C+methods.%5C+By%5C+the%5C+modern%5C+techniques%5C+of%5C+chromatography%2C%5C+spectroscopy%5C+along%5C+with%5C+chemical%5C+degradation%5C+methods%2C%5C+107%5C+compounds%5C+were%5C+isolated%5C+and%5C+identified%5C+by%5C+MS%2C%5C+1D%5C+and%5C+2D%5C+NMR%5C+spectra%5C+along%5C+with%5C+other%5C+spectroscopic%5C+method%5C+along%5C+with%5C+chemical%5C+degradation.%5C+The%5C+compounds%5C+include%5C+hydrolysable%5C+tannins%2C%5C+flavan%5C-3ols%2C%5C+flavonoid%5C+glycosides%2C%5C+triterpene%5C+glycosides%2C%5C+simple%5C+phenolics%5C+and%5C+so%5C+on%2C%5C+most%5C+of%5C+which%5C+were%5C+evaluated%5C+by%5C+antioxidant%5C+or%5C+anti%5C-viral%5C+activities.%5C+Meantime%2C%5C+the%5C+HPLC%5C+analytical%5C+methods%5C+were%5C+applied%5C+to%5C+compare%5C+the%5C+chemical%5C+constituents%5C+of%5C+C.%5C+taliensis%5C+and%5C+C.%5C+pachyandra%5C+with%5C+with%5C+those%5C+of%5C+the%5C+cultivated%5C+tea%2C%5C+C.%5C+sinensis%5C+var.%5C+assamica.%5C+Above%5C+all%2C%5C+the%5C+detection%5C+methods%5C+were%5C+established%5C+for%5C+the%5C+analysis%5C+of%5C+tea%5C+polyphenols%2C%5C+tea%5C+polysaccharides%2C%5C+caffeine%5C+and%5C+the%5C+main%5C+polyphenolic%5C+constituents%5C+in%5C+tea.%5C+And%5C+finally%2C%5C+the%5C+progress%5C+of%5C+the%5C+research%5C+work%5C+on%5C+Pu%5C-er%5C+tea%5C+was%5C+reviewed."},{"jsname":"the combination of Rodgersia, Astilboides, Darmera, Oresitrophe, Bergenia, and Mukdenia by Soltis with the name of Darmera group was supported. The key taxonomic traits of leave arrangement and pubescence were not suppoted by molecular result, especially for taxa from Hengduan Mountains and Himalayas. Multiple sampled Rodgersia aesculifolia was not monophyly, samples from Hengduan Mountains (R. henrici = R. aesculifolia var. henrici) were nested with R. pinnata and R. sambucifolia, while samples from southeast Tibet (R. henrici = R. aesculifolia var. henrici) form a clade sister to the former taxa. Samples of R. aesculifolia from Qingling and Daba mountains (R. aesculifolia var. aesculifolia = Triditional R. asculifolia) are distinct with all the above. R. aesculifolia var. henrici is distinct from A. aesculifolia var. aesculifolia and is suggested be raised to spcies level again as Rosgersia henrici Franchet. Populations of R. henrici from western Yunnan are grouping with R. pinnata, natural hybridization are supposed to occur. Rodgersia podophylla from Korea and Japan is sister to Chinese Rodgersia. The furthermore study of infraspecific taxonomy of R. aesculifolia is suggested.The relict Rodgersia nepalensis from eastern Nepal branched first in the combined ITS and plastid tree, which is different from evidences of the traditional morphology and cytology. This might due to its narrow distribution disjuct from other species of Rodgersia, low level of gene flow and subsequent conserved genetic system. It may evolved by polyploidy, the spcecialized morphological character of R. nepalensis may be a strategy for ecological tolerance and self-protection. Our molecular phylogeny of Rodgersia is accordant with the former morphological and cytological evidences. Hybridization and polyploidy may play an important role in evolution and speciation in Rodgersia. Rodgersia may origin from northestern Asia and migrated into Hengduan mountains and Himalayas through Qingling and Daba mountains. Based on present molecular results, as well as original description papers and Type specimen, six species and two variaties were recognized in Rodgersia. Rodgersia henrici was recognized in our study, and was supported to be raised to species level again","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=%25E6%2596%25B0%25E7%25BB%2584%25E5%2590%2588&&fq=dc.project.title_filter%3Athe%5C+combination%5C+of%5C+Rodgersia%2C%5C+Astilboides%2C%5C+Darmera%2C%5C+Oresitrophe%2C%5C+Bergenia%2C%5C+and%5C+Mukdenia%5C+by%5C+Soltis%5C+with%5C+the%5C+name%5C+of%5C+Darmera%5C+group%5C+was%5C+supported.%5C+The%5C+key%5C+taxonomic%5C+traits%5C+of%5C+leave%5C+arrangement%5C+and%5C+pubescence%5C+were%5C+not%5C+suppoted%5C+by%5C+molecular%5C+result%2C%5C+especially%5C+for%5C+taxa%5C+from%5C+Hengduan%5C+Mountains%5C+and%5C+Himalayas.%5C+Multiple%5C+sampled%5C+Rodgersia%5C+aesculifolia%5C+was%5C+not%5C+monophyly%2C%5C+samples%5C+from%5C+Hengduan%5C+Mountains%5C+%5C%28R.%5C+henrici%5C+%3D%5C+R.%5C+aesculifolia%5C+var.%5C+henrici%5C%29%5C+were%5C+nested%5C+with%5C+R.%5C+pinnata%5C+and%5C+R.%5C+sambucifolia%2C%5C+while%5C+samples%5C+from%5C+southeast%5C+Tibet%5C+%5C%28R.%5C+henrici%5C+%3D%5C+R.%5C+aesculifolia%5C+var.%5C+henrici%5C%29%5C+form%5C+a%5C+clade%5C+sister%5C+to%5C+the%5C+former%5C+taxa.%5C+Samples%5C+of%5C+R.%5C+aesculifolia%5C+from%5C+Qingling%5C+and%5C+Daba%5C+mountains%5C+%5C%28R.%5C+aesculifolia%5C+var.%5C+aesculifolia%5C+%3D%5C+Triditional%5C+R.%5C+asculifolia%5C%29%5C+are%5C+distinct%5C+with%5C+all%5C+the%5C+above.%5C+R.%5C+aesculifolia%5C+var.%5C+henrici%5C+is%5C+distinct%5C+from%5C+A.%5C+aesculifolia%5C+var.%5C+aesculifolia%5C+and%5C+is%5C+suggested%5C+be%5C+raised%5C+to%5C+spcies%5C+level%5C+again%5C+as%5C+Rosgersia%5C+henrici%5C+Franchet.%5C+Populations%5C+of%5C+R.%5C+henrici%5C+from%5C+western%5C+Yunnan%5C+are%5C+grouping%5C+with%5C+R.%5C+pinnata%2C%5C+natural%5C+hybridization%5C+are%5C+supposed%5C+to%5C+occur.%5C+Rodgersia%5C+podophylla%5C+from%5C+Korea%5C+and%5C+Japan%5C+is%5C+sister%5C+to%5C+Chinese%5C+Rodgersia.%5C+The%5C+furthermore%5C+study%5C+of%5C+infraspecific%5C+taxonomy%5C+of%5C+R.%5C+aesculifolia%5C+is%5C+suggested.The%5C+relict%5C+Rodgersia%5C+nepalensis%5C+from%5C+eastern%5C+Nepal%5C+branched%5C+first%5C+in%5C+the%5C+combined%5C+ITS%5C+and%5C+plastid%5C+tree%2C%5C+which%5C+is%5C+different%5C+from%5C+evidences%5C+of%5C+the%5C+traditional%5C+morphology%5C+and%5C+cytology.%5C+This%5C+might%5C+due%5C+to%5C+its%5C+narrow%5C+distribution%5C+disjuct%5C+from%5C+other%5C+species%5C+of%5C+Rodgersia%2C%5C+low%5C+level%5C+of%5C+gene%5C+flow%5C+and%5C+subsequent%5C+conserved%5C+genetic%5C+system.%5C+It%5C+may%5C+evolved%5C+by%5C+polyploidy%2C%5C+the%5C+spcecialized%5C+morphological%5C+character%5C+of%5C+R.%5C+nepalensis%5C+may%5C+be%5C+a%5C+strategy%5C+for%5C+ecological%5C+tolerance%5C+and%5C+self%5C-protection.%5C+Our%5C+molecular%5C+phylogeny%5C+of%5C+Rodgersia%5C+is%5C+accordant%5C+with%5C+the%5C+former%5C+morphological%5C+and%5C+cytological%5C+evidences.%5C+Hybridization%5C+and%5C+polyploidy%5C+may%5C+play%5C+an%5C+important%5C+role%5C+in%5C+evolution%5C+and%5C+speciation%5C+in%5C+Rodgersia.%5C+Rodgersia%5C+may%5C+origin%5C+from%5C+northestern%5C+Asia%5C+and%5C+migrated%5C+into%5C+Hengduan%5C+mountains%5C+and%5C+Himalayas%5C+through%5C+Qingling%5C+and%5C+Daba%5C+mountains.%5C+Based%5C+on%5C+present%5C+molecular%5C+results%2C%5C+as%5C+well%5C+as%5C+original%5C+description%5C+papers%5C+and%5C+Type%5C+specimen%2C%5C+six%5C+species%5C+and%5C+two%5C+variaties%5C+were%5C+recognized%5C+in%5C+Rodgersia.%5C+Rodgersia%5C+henrici%5C+was%5C+recognized%5C+in%5C+our%5C+study%2C%5C+and%5C+was%5C+supported%5C+to%5C+be%5C+raised%5C+to%5C+species%5C+level%5C+again"},{"jsname":"lastIndexed","jscount":"2024-09-19"}],"资助项目","dc.project.title_filter")'>
|
|
|
|
|
