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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 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Saccharinae Kuntze belongs to the tribe Andropogoneae, subfamily Panicoideae, Poaceae. There are about 156 species in the world, with 66 species occurring in China. They are distributed throughout China, mostly in the Provinces of the south and southwest. They are especially abundant in the mid and lower reaches of the Changjiang and its tributaries. A few species extend to northern China. Saccharinae grasses are usually tall, with many species being cultivated as agricultural crop plants and others possessing commercial value. In many parts of the world, selected species are currently undergoing trials as potential target plants for the exploitation of new energy sources. However, there are many taxonomic problems remaining within Saccharinae and historic studies are both incomplete and inconclusive. Problems exist and opinions differ on the systematic positioning of several genera and species. Conclusions which led to this taxonomic revision utilized the following tools and methods: field works; literature research; the study of 7069 specimens and photos from 17 herbaria; leaf anatomical experiments; analysis of the morphological characters (using statistic methodology).Generic revisions:1. Pseudopogonatherum and Eulalia are quite different in their morphology, leaf epidermis and transverse characteristics. They should be treated as two separate genera. This is consistent with the earlier opinions of Bor and S. L. Chen.2. The leaf anatomical structures and morphological characteristics in Diandranthus, Miscanthus, Triarrhena and Rubimons are almost all the same except for a few differences which exist in Rubimons. According to the result, Diandranthus, Triarrhena and Rubimons should be included in to Miscanthus as described in The Flora of China, but the subgenus Miscanthus subgen. Rubimons (B. S. Sun) Y. C. Liu et H. Peng is usefully aligned to the distinct Rubimons taxa.3. The leaf anatomical structures of Saccharum, Erianthus and Narenga show significant similarity. We agree with Clayton’s suggestion that Erianthus and Narenga should be included into Saccharum.4. The study result of leaf anatomy and morphology in Eccoilopus and Spodiopogon indicate that Eccoilopus should be included with Spodiopogon which agrees with the taxonomic treatment in Genera Graminum, Flora Yunnanica and Flora of China.On Species:1. According to the statistical research and characteristics comparison, we conclude that Microstegium reticulatum should be treated as a synonym of Microstegium vimineum; Miscanthus purpurascence should be included with Miscanthus sinensis; Saccharum arundinaceum var. trichophyllum is simply an extreme variation of Saccharum arundinaceum, and should be treated as a synonym of the latter.2. Specimens labeled as Eulalia siamensis and Eulalia wightii in Chinese herbaria are actually specimens of Eulalia quadrinervis, and specimens labeled as Imperata cylindrica var. cylindrica are in fact specimens of Imperata cylindrica var. major, which means that Eulalia siamensis, Eulalia wightii and Imperata cylindrica var. cylindrica do not occur in China.3. The specimens of Microstegium fasciculatum in Chinese herbaria have long been identified as Microstegium ciliatum. And the descriptions in Flora illustralis Plantarum Primarium Sinicarum Poaceae, Flora Reipublicae Popularis Sinicae Tomus 10(2) and Flora Yunnanica Tomus 9 were wrong in some key details. The correct description of Microstegium ciliatum is available in Flora of China Vol. 22.4. Two new species are found: Miscanthus villosus Y. C. Liu et H. Peng Sp. Nov. and Microstegium butuoense Y. C. Liu et H. Peng Sp. Nov.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&fq=location.comm.id%3A1&query1=Target%2BAnalysis&&fq=dc.project.title_filter%3ASubtrib.%5C+Saccharinae%5C+Kuntze%5C+belongs%5C+to%5C+the%5C+tribe%5C+Andropogoneae%2C%5C+subfamily%5C+Panicoideae%2C%5C+Poaceae.%5C+There%5C+are%5C+about%5C+156%5C+species%5C+in%5C+the%5C+world%2C%5C+with%5C+66%5C+species%5C+occurring%5C+in%5C+China.%5C+They%5C+are%5C+distributed%5C+throughout%5C+China%2C%5C+mostly%5C+in%5C+the%5C+Provinces%5C+of%5C+the%5C+south%5C+and%5C+southwest.%5C+They%5C+are%5C+especially%5C+abundant%5C+in%5C+the%5C+mid%5C+and%5C+lower%5C+reaches%5C+of%5C+the%5C+Changjiang%5C+and%5C+its%5C+tributaries.%5C+A%5C+few%5C+species%5C+extend%5C+to%5C+northern%5C+China.%5C+Saccharinae%5C+grasses%5C+are%5C+usually%5C+tall%2C%5C+with%5C+many%5C+species%5C+being%5C+cultivated%5C+as%5C+agricultural%5C+crop%5C+plants%5C+and%5C+others%5C+possessing%5C+commercial%5C+value.%5C+In%5C+many%5C+parts%5C+of%5C+the%5C+world%2C%5C+selected%5C+species%5C+are%5C+currently%5C+undergoing%5C+trials%5C+as%5C+potential%5C+target%5C+plants%5C+for%5C+the%5C+exploitation%5C+of%5C+new%5C+energy%5C+sources.%5C+However%2C%5C+there%5C+are%5C+many%5C+taxonomic%5C+problems%5C+remaining%5C+within%5C+Saccharinae%5C+and%5C+historic%5C+studies%5C+are%5C+both%5C+incomplete%5C+and%5C+inconclusive.%5C+Problems%5C+exist%5C+and%5C+opinions%5C+differ%5C+on%5C+the%5C+systematic%5C+positioning%5C+of%5C+several%5C+genera%5C+and%5C+species.%5C+Conclusions%5C+which%5C+led%5C+to%5C+this%5C+taxonomic%5C+revision%5C+utilized%5C+the%5C+following%5C+tools%5C+and%5C+methods%5C%3A%5C+field%5C+works%5C%3B%5C+literature%5C+research%5C%3B%5C+the%5C+study%5C+of%5C+7069%5C+specimens%5C+and%5C+photos%5C+from%5C+17%5C+herbaria%5C%3B%5C+leaf%5C+anatomical%5C+experiments%5C%3B%5C+analysis%5C+of%5C+the%5C+morphological%5C+characters%5C+%5C%28using%5C+statistic%5C+methodology%5C%29.Generic%5C+revisions%5C%3A1.%5C+Pseudopogonatherum%5C+and%5C+Eulalia%5C+are%5C+quite%5C+different%5C+in%5C+their%5C+morphology%2C%5C+leaf%5C+epidermis%5C+and%5C+transverse%5C+characteristics.%5C+They%5C+should%5C+be%5C+treated%5C+as%5C+two%5C+separate%5C+genera.%5C+This%5C+is%5C+consistent%5C+with%5C+the%5C+earlier%5C+opinions%5C+of%5C+Bor%5C+and%5C+S.%5C+L.%5C+Chen.2.%5C+The%5C+leaf%5C+anatomical%5C+structures%5C+and%5C+morphological%5C+characteristics%5C+in%5C+Diandranthus%2C%5C+Miscanthus%2C%5C+Triarrhena%5C+and%5C+Rubimons%5C+are%5C+almost%5C+all%5C+the%5C+same%5C+except%5C+for%5C+a%5C+few%5C+differences%5C+which%5C+exist%5C+in%5C+Rubimons.%5C+According%5C+to%5C+the%5C+result%2C%5C+Diandranthus%2C%5C+Triarrhena%5C+and%5C+Rubimons%5C+should%5C+be%5C+included%5C+in%5C+to%5C+Miscanthus%5C+as%5C+described%5C+in%5C+The%5C+Flora%5C+of%5C+China%2C%5C+but%5C+the%5C+subgenus%5C+Miscanthus%5C+subgen.%5C+Rubimons%5C+%5C%28B.%5C+S.%5C+Sun%5C%29%5C+Y.%5C+C.%5C+Liu%5C+et%5C+H.%5C+Peng%5C+is%5C+usefully%5C+aligned%5C+to%5C+the%5C+distinct%5C+Rubimons%5C+taxa.3.%5C+The%5C+leaf%5C+anatomical%5C+structures%5C+of%5C+Saccharum%2C%5C+Erianthus%5C+and%5C+Narenga%5C+show%5C+significant%5C+similarity.%5C+We%5C+agree%5C+with%5C+Clayton%E2%80%99s%5C+suggestion%5C+that%5C+Erianthus%5C+and%5C+Narenga%5C+should%5C+be%5C+included%5C+into%5C+Saccharum.4.%5C+The%5C+study%5C+result%5C+of%5C+leaf%5C+anatomy%5C+and%5C+morphology%5C+in%5C+Eccoilopus%5C+and%5C+Spodiopogon%5C+indicate%5C+that%5C+Eccoilopus%5C+should%5C+be%5C+included%5C+with%5C+Spodiopogon%5C+which%5C+agrees%5C+with%5C+the%5C+taxonomic%5C+treatment%5C+in%5C+Genera%5C+Graminum%2C%5C+Flora%5C+Yunnanica%5C+and%5C+Flora%5C+of%5C+China.On%5C+Species%5C%3A1.%5C+According%5C+to%5C+the%5C+statistical%5C+research%5C+and%5C+characteristics%5C+comparison%2C%5C+we%5C+conclude%5C+that%5C+Microstegium%5C+reticulatum%5C+should%5C+be%5C+treated%5C+as%5C+a%5C+synonym%5C+of%5C+Microstegium%5C+vimineum%5C%3B%5C+Miscanthus%5C+purpurascence%5C+should%5C+be%5C+included%5C+with%5C+Miscanthus%5C+sinensis%5C%3B%5C+Saccharum%5C+arundinaceum%5C+var.%5C+trichophyllum%5C+is%5C+simply%5C+an%5C+extreme%5C+variation%5C+of%5C+Saccharum%5C+arundinaceum%2C%5C+and%5C+should%5C+be%5C+treated%5C+as%5C+a%5C+synonym%5C+of%5C+the%5C+latter.2.%5C+Specimens%5C+labeled%5C+as%5C+Eulalia%5C+siamensis%5C+and%5C+Eulalia%5C+wightii%5C+in%5C+Chinese%5C+herbaria%5C+are%5C+actually%5C+specimens%5C+of%5C+Eulalia%5C+quadrinervis%2C%5C+and%5C+specimens%5C+labeled%5C+as%5C+Imperata%5C+cylindrica%5C+var.%5C+cylindrica%5C+are%5C+in%5C+fact%5C+specimens%5C+of%5C+Imperata%5C+cylindrica%5C+var.%5C+major%2C%5C+which%5C+means%5C+that%5C+Eulalia%5C+siamensis%2C%5C+Eulalia%5C+wightii%5C+and%5C+Imperata%5C+cylindrica%5C+var.%5C+cylindrica%5C+do%5C+not%5C+occur%5C+in%5C+China.3.%5C+The%5C+specimens%5C+of%5C+Microstegium%5C+fasciculatum%5C+in%5C+Chinese%5C+herbaria%5C+have%5C+long%5C+been%5C+identified%5C+as%5C+Microstegium%5C+ciliatum.%5C+And%5C+the%5C+descriptions%5C+in%5C+Flora%5C+illustralis%5C+Plantarum%5C+Primarium%5C+Sinicarum%5C+Poaceae%2C%5C+Flora%5C+Reipublicae%5C+Popularis%5C+Sinicae%5C+Tomus%5C+10%5C%282%5C%29%5C+and%5C+Flora%5C+Yunnanica%5C+Tomus%5C+9%5C+were%5C+wrong%5C+in%5C+some%5C+key%5C+details.%5C+The%5C+correct%5C+description%5C+of%5C+Microstegium%5C+ciliatum%5C+is%5C+available%5C+in%5C+Flora%5C+of%5C+China%5C+Vol.%5C+22.4.%5C+Two%5C+new%5C+species%5C+are%5C+found%5C%3A%5C+Miscanthus%5C+villosus%5C+Y.%5C+C.%5C+Liu%5C+et%5C+H.%5C+Peng%5C+Sp.%5C+Nov.%5C+and%5C+Microstegium%5C+butuoense%5C+Y.%5C+C.%5C+Liu%5C+et%5C+H.%5C+Peng%5C+Sp.%5C+Nov."},{"jsname":"The chemistry constitutes and their anti-tobacco mosic virus activity from two species of Simaroubeaceae, namely Brucea javanica (L) Merr. and Harrisonia perforata (Blanco) Merr have been investigated.. By variety of chromatographies over various materials, Eighty-seven compounds were isolated from the two plants and eighty of them were identified， of which twenty-two were new compounds and one of them was a novel nortriterpenoids with unprecedented skeleton and another showed the polymorphism. A series of C-20 quassinoids with potent anti-tobacco mosic virus (TMV) activity was found by the bioassay-guided isolation of the seed of Brucea javanica. The characteristic secondary metabolites of Simaroubeaceae--quassinoids were reviewed. Chapter 1, phytochemistry investigation on the seed of Brucea javanica (L) Merr. has led to isolation of 41 compounds, and 34 of them were identified, including 17 quassinoids with anti-TMV activity. Among them compounds 1 and 2 were new quassinoids. Others were alkaloids, ligands, sequiterpenoids, and so on. Chapter 2, tobacco mosic virus inhibiting activity of quassinoids from Brucea javanica (L) Merr. From bioassay-guide isolation 17 quassinoids with potent anti-TMV activities were isolated from the seeds of Brucea javanica (L) Merr. Based on the results of in vivo and in vitro experiments, it was showed that those compounds can both inhibit virus infection and multiplication of TMV. The anti-TMV structure activity relationships were also discussed. Chapter 3, phytochemistry investigation on the leaves and branches of H. perforata has lead to isolation of 32 compounds and 31 were identified, including 20 new limonoids. Among them 1 was a novel limonoids with unprecedented skeleton, and another showed the polymorphism. Besides, 14 compounds, including 8 limonoids along with some triterpenoids, ligands and flavonoids were isolated from the fruit of H. perforata. Among the 14 compounds 1-3 were novel limonoids which have been isolated from the leaves and branches of this species. The limonoids isolated from H. perforata showed structure similarity with those from the Ptaeroxylaceae and Cneoraceae. Furthermore, most of them were the key intermediates of the biogenetic pathway previously proposed by Dr. Xin Fang of our research group. Based on the biogenetic pathway and structure similarity of limonoids it was suggested that the genus of Harrisonia has a very close relationship with Ptaeroxylaceae and Cneoraceae. Chapter 4, reviewed the progress on the phytochemistry study of the quassinoids of Simaroubaceae. The bioactivities along with proposed biogenetic pathway involving quassinoids reported from the Simaroubeaceae were systemically.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&fq=location.comm.id%3A1&query1=Target%2BAnalysis&&fq=dc.project.title_filter%3AThe%5C+chemistry%5C+constitutes%5C+and%5C+their%5C+anti%5C-tobacco%5C+mosic%5C+virus%5C+activity%5C+from%5C+two%5C+species%5C+of%5C+Simaroubeaceae%2C%5C+namely%5C+Brucea%5C+javanica%5C+%5C%28L%5C%29%5C+Merr.%5C+and%5C+Harrisonia%5C+perforata%5C+%5C%28Blanco%5C%29%5C+Merr%5C+have%5C+been%5C+investigated..%5C+By%5C+variety%5C+of%5C+chromatographies%5C+over%5C+various%5C+materials%2C%5C+Eighty%5C-seven%5C+compounds%5C+were%5C+isolated%5C+from%5C+the%5C+two%5C+plants%5C+and%5C+eighty%5C+of%5C+them%5C+were%5C+identified%EF%BC%8C%5C+of%5C+which%5C+twenty%5C-two%5C+were%5C+new%5C+compounds%5C+and%5C+one%5C+of%5C+them%5C+was%5C+a%5C+novel%5C+nortriterpenoids%5C+with%5C+unprecedented%5C+skeleton%5C+and%5C+another%5C+showed%5C+the%5C+polymorphism.%5C+A%5C+series%5C+of%5C+C%5C-20%5C+quassinoids%5C+with%5C+potent%5C+anti%5C-tobacco%5C+mosic%5C+virus%5C+%5C%28TMV%5C%29%5C+activity%5C+was%5C+found%5C+by%5C+the%5C+bioassay%5C-guided%5C+isolation%5C+of%5C+the%5C+seed%5C+of%5C+Brucea%5C+javanica.%5C+The%5C+characteristic%5C+secondary%5C+metabolites%5C+of%5C+Simaroubeaceae%5C-%5C-quassinoids%5C+were%5C+reviewed.%5C+Chapter%5C+1%2C%5C+phytochemistry%5C+investigation%5C+on%5C+the%5C+seed%5C+of%5C+Brucea%5C+javanica%5C+%5C%28L%5C%29%5C+Merr.%5C+has%5C+led%5C+to%5C+isolation%5C+of%5C+41%5C+compounds%2C%5C+and%5C+34%5C+of%5C+them%5C+were%5C+identified%2C%5C+including%5C+17%5C+quassinoids%5C+with%5C+anti%5C-TMV%5C+activity.%5C+Among%5C+them%5C+compounds%5C+1%5C+and%5C+2%5C+were%5C+new%5C+quassinoids.%5C+Others%5C+were%5C+alkaloids%2C%5C+ligands%2C%5C+sequiterpenoids%2C%5C+and%5C+so%5C+on.%5C+Chapter%5C+2%2C%5C+tobacco%5C+mosic%5C+virus%5C+inhibiting%5C+activity%5C+of%5C+quassinoids%5C+from%5C+Brucea%5C+javanica%5C+%5C%28L%5C%29%5C+Merr.%5C+From%5C+bioassay%5C-guide%5C+isolation%5C+17%5C+quassinoids%5C+with%5C+potent%5C+anti%5C-TMV%5C+activities%5C+were%5C+isolated%5C+from%5C+the%5C+seeds%5C+of%5C+Brucea%5C+javanica%5C+%5C%28L%5C%29%5C+Merr.%5C+Based%5C+on%5C+the%5C+results%5C+of%5C+in%5C+vivo%5C+and%5C+in%5C+vitro%5C+experiments%2C%5C+it%5C+was%5C+showed%5C+that%5C+those%5C+compounds%5C+can%5C+both%5C+inhibit%5C+virus%5C+infection%5C+and%5C+multiplication%5C+of%5C+TMV.%5C+The%5C+anti%5C-TMV%5C+structure%5C+activity%5C+relationships%5C+were%5C+also%5C+discussed.%5C+Chapter%5C+3%2C%5C+phytochemistry%5C+investigation%5C+on%5C+the%5C+leaves%5C+and%5C+branches%5C+of%5C+H.%5C+perforata%5C+has%5C+lead%5C+to%5C+isolation%5C+of%5C+32%5C+compounds%5C+and%5C+31%5C+were%5C+identified%2C%5C+including%5C+20%5C+new%5C+limonoids.%5C+Among%5C+them%5C+1%5C+was%5C+a%5C+novel%5C+limonoids%5C+with%5C+unprecedented%5C+skeleton%2C%5C+and%5C+another%5C+showed%5C+the%5C+polymorphism.%5C+Besides%2C%5C+14%5C+compounds%2C%5C+including%5C+8%5C+limonoids%5C+along%5C+with%5C+some%5C+triterpenoids%2C%5C+ligands%5C+and%5C+flavonoids%5C+were%5C+isolated%5C+from%5C+the%5C+fruit%5C+of%5C+H.%5C+perforata.%5C+Among%5C+the%5C+14%5C+compounds%5C+1%5C-3%5C+were%5C+novel%5C+limonoids%5C+which%5C+have%5C+been%5C+isolated%5C+from%5C+the%5C+leaves%5C+and%5C+branches%5C+of%5C+this%5C+species.%5C+The%5C+limonoids%5C+isolated%5C+from%5C+H.%5C+perforata%5C+showed%5C+structure%5C+similarity%5C+with%5C+those%5C+from%5C+the%5C+Ptaeroxylaceae%5C+and%5C+Cneoraceae.%5C+Furthermore%2C%5C+most%5C+of%5C+them%5C+were%5C+the%5C+key%5C+intermediates%5C+of%5C+the%5C+biogenetic%5C+pathway%5C+previously%5C+proposed%5C+by%5C+Dr.%5C+Xin%5C+Fang%5C+of%5C+our%5C+research%5C+group.%5C+Based%5C+on%5C+the%5C+biogenetic%5C+pathway%5C+and%5C+structure%5C+similarity%5C+of%5C+limonoids%5C+it%5C+was%5C+suggested%5C+that%5C+the%5C+genus%5C+of%5C+Harrisonia%5C+has%5C+a%5C+very%5C+close%5C+relationship%5C+with%5C+Ptaeroxylaceae%5C+and%5C+Cneoraceae.%5C+Chapter%5C+4%2C%5C+reviewed%5C+the%5C+progress%5C+on%5C+the%5C+phytochemistry%5C+study%5C+of%5C+the%5C+quassinoids%5C+of%5C+Simaroubaceae.%5C+The%5C+bioactivities%5C+along%5C+with%5C+proposed%5C+biogenetic%5C+pathway%5C+involving%5C+quassinoids%5C+reported%5C+from%5C+the%5C+Simaroubeaceae%5C+were%5C+systemically."},{"jsname":"The origin center and diversity center of the genus Ligularia were considered to be central China and Hengduan Mountains Region (HMR) of China, respectively. In this research, we studied the phylogeographic pattern of L. hodgsonii and L. tongolensis, which was distributed in the origin center and diversity center, respectively. We aimed to infer the evolutionary process of Ligularia species. 1. The phylogeography of L. hodgsonii，Here, we investigated the phylogeographic history of L. hodgsonii disjunctively distributed in China and Japan. Two hundred and eighty individuals were collected from 29 natural populations, 23 located in China and 6 in Japan. A total of 19 haplotypes were identified with the combination of three chloroplast DNA (cpDNA) sequences variations (trnQ-5’rps16, trnL-rpl32 and psbA-trnH). At the species level, a high level of haplotype diversity (Hd) and total genetic diversity (HT) was detected. However, the average intrapopulation diversity (HS) was very low. Consequently, the population differentiation(NST = 0.989, GST = 0.933 ) was pronounced with a significant phylogeographic structure (NST > GST, p < 0.01). At the regional level, Chinese and Japanese L. hodgsonii had a similar estimate of genetic diversity (China: Hd = 0.847, HT = 0.869; Japan: Hd = 0.766, HT = 0.867). Populations from China and Japan possess unique sets of haplotypes, and no haplotypes were shared between the regions. Furthermore, both the phyloegenetic and network analyses recovered the haplotypes of China and Japan as two distinct clades. Thus, we suggested the disjunct distribution of L. hodgsonii in China and Japan may present the climatic vicariant relicts of the ancient widely distributed populations. After divergence, this species within each region experienced independent evolutionary process. In China, L. hodgsonii was distributed around the Sichuan Basin. This distribution range can be divided into five regions. They were Jiajin Mountain region, E’mei Mountain region, Yunnan-Guizhou Plateau region, Wushan-Wuling Mountain region and Qinling Mountain region. Twelve haplotypes were indentified within these regions. Each region had its own specific haplotypes, which had different ancestry in the network. We deduced that Chinese L. hodgsonii might survive the LGM in multiple isolated refugia around the Sichuan Basin. In Japan, L. hodgsonii was disjunctively distributed in northern Honshu and Hokkaido. Seven haplotypes were identified within this region. However, the genetic diversity in Honshu (Hd = 0.821) was much higher than that in Hokkaido (Hd = 0.513). And all haplotypes in Hokkaido were derived from Honshu. This haplotype distribution suggested that the northern Honshu could have served as refuge in Japan. Nested clade analysis (NCA) indicated multiple forces including the vicariance and long-distance dispersal affected the disjunctive distribution among populations of L. hodgsonii in Japan.2. The phylogeography of L. tongolensis，Ligularia tongolensis was distributed along the Jinshajiang watershed, Yalongjiang watershed and Wumeng Mountain. In order to deduce the demographic history of this species, we sequenced two chloroplast DNA (cpDNA) intergenic spacers (trnQ-5’rps16, trnL-rpl32) in 140 individuals from 14 populations of three groups (Jinshajiang vs. Yalongjiang vs. Wumeng) within this species range. High levels of haplotype diversity (Hd = 0.814) and total genetic diversity (HT = 0.862) were detected at the species level, based on a total oftwelve haplotypes identified. However, the intrapopulation diversity (HS = 0.349) was low, which led to the high levels of genetic divergence (GST = 0.595, NST = 0.614, FST = 0.597). In consideration of the speciation of L. tongolensis resulting from the uplifts of the Qinghai-Tibetan Plateau (QTP), we thought the present genetic structure of L. tongolensis was shaped by the fragmentation of ancestral populations during the courses of QTP uplifts. This was further supported by the absence of IBD tests (r = –0.291, p = 0.964), which suggest that the differentiation had not occurred in accordance with the isolation by distance model. The genetic differentiation in L. tongolensis appears to be associated with historical events. Meanwhile, H2 and H5, the dominant haplotypes that located on internal nodes and deviated from extinct ancestral haplotype in the network, were detected to be shared between Jinshajiang and Yalongjiang groups. We deduced that ancestral populations of this species might have had a continuous distribution range, which was then fragmented and isolated by the following tectonic events. Finally, the ancestral polymorphism, H2 and H5, were randomly allocated in Jinshajiang watershed and Yalongjiang watershed. Meanwhile, H5 was the dominant haplotype in Jinshajiang watershed; H7 was the domiant haplotype in Yalongjiang watershed and Wumeng Mountain. This haplotype distribution pattern indicated that each group might have served as a refuge for L. tongolensis during the Quaternary Glaciation. Postglacial demographic expansion was supported by unimodal mismatch distribution and star-like phylogenies, with expansion ages of 274 ka B. P. for this 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