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资助项目
0.05) between wild (AR = 4.651), semi-cultivated (AR = 5.091) and cultivated (AR = 5.132) populations of C. taliensis, which suggested that the genetic background of long-lived woody plant was not easy to be changed, and there were moderate high gene flow between populations. However, there was a significant difference (P < 0.05) between wild (AR = 5.9) and cultivated (AR = 7.1) populations distributed in the same place in Yun county, Yunnan province, which may result from the hybridization and introgression of species in the tea garden and anthropogenic damages to the wild population. The hypothesis of hybrid origin of C. grandibracteata was tested by morphological and microsatellites analyses. Compared with other species, the locules in ovary of C. grandibracteata are variable, which showed a morphological intermediate and mosaic. Except one private allele, Ninety-nine percent alleles of C. grandibracteata were shared with these of C. taliensis and C. sinensis var. assamica. And C. grandibracteata was nested in the cluster of C. taliensis in the UPGMA tree. Conclusively, our results supported the hypothesis of hybrid origin of C. grandibracteata partly. The speciation of C. grandibracteata was derived from hybridization and asymmetrical introgression potentially. It is possible that C. taliensis was one of its parents, but it still needs more evidences to prove that C. sinensis var. assamica was another parent.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3ACamellia%5C+taliensis%5C+%5C%28W.%5C+W.%5C+Smith%5C%29%5C+Melchior%2C%5C+a%5C+member%5C+of%5C+Camellia%5C+sect.%5C+Thea%2C%5C+is%5C+an%5C+indigenous%5C+species%5C+in%5C+local%5C+natural%5C+forest%5C+and%5C+has%5C+a%5C+long%5C+cultivative%5C+history%5C+in%5C+western%5C+Yunnan%5C+and%5C+its%5C+neighborhood%2C%5C+where%5C+the%5C+domestications%5C+of%5C+this%5C+species%5C+in%5C+different%5C+historical%5C+periods%5C+and%5C+in%5C+different%5C+ways%5C+can%5C+be%5C+found.%5C+C.%5C+taliensis%5C+is%5C+an%5C+important%5C+contributor%5C+to%5C+the%5C+formations%5C+of%5C+tea%5C+landraces%5C+by%5C+hybridization%5C+and%5C+introgression.%5C+In%5C+the%5C+present%5C+study%2C%5C+14%5C+microsatellite%5C+loci%5C+screened%5C+from%5C+37%5C+loci%5C+were%5C+used%5C+to%5C+explore%5C+the%5C+genetic%5C+diversity%5C+about%5C+this%5C+species%5C+with%5C+579%5C+samples%5C+from%5C+25%5C+populations%5C+%5C%2816%5C+wild%5C+populations%2C%5C+4%5C+semi%5C-cultivated%5C+populations%5C+and%5C+5%5C+cultivated%5C+populations%5C%29.%5C+At%5C+the%5C+same%5C+time%2C%5C+the%5C+potential%5C+hybrid%5C+speciation%5C+of%5C+C.%5C+grandibracteata%2C%5C+was%5C+investigated%5C+using%5C+39%5C+individuals%5C+from%5C+2%5C+populations%2C%5C+along%5C+with%5C+C.%5C+taliensis%5C+and%5C+C.%5C+sinensis%5C+var.%5C+assamica%5C+%5C%2883%5C+individuals%5C+from%5C+4%5C+populations%5C%29%5C+by%5C+the%5C+same%5C+microsatellite%5C+markers.%5C+C.%5C+taliensis%5C+had%5C+a%5C+moderate%5C+high%5C+level%5C+of%5C+genetic%5C+diversity%5C+%5C%28A%5C+%3D%5C+14.3%2C%5C+Ne%3D%5C+5.7%2C%5C+HE%5C+%3D%5C+0.666%2C%5C+I%5C+%3D%5C+1.753%2C%5C+AR%5C+%3D%5C+7.2%2C%5C+PPB%5C+%3D%5C+100%25%5C%29.%5C+This%5C+may%5C+result%5C+from%5C+several%5C+factors%5C+including%5C+K%5C-strategy%2C%5C+genetic%5C+background%2C%5C+gene%5C+flow%5C+between%5C+populations%2C%5C+hybridization%5C+and%5C+introgression%5C+among%5C+species.%5C+Between%5C+wild%5C+populations%5C+of%5C+C.%5C+taliensis%2C%5C+the%5C+gene%5C+flow%5C+was%5C+moderate%5C+high%5C+%5C%28Nm%5C+%3D%5C+1.197%5C%29%2C%5C+and%5C+genetic%5C+variation%5C+was%5C+less%5C+than%5C+20%25%5C+%5C%28GST%5C+%3D%5C+0.147%2C%5C+FST%5C+%3D%5C+0.173%5C%29%2C%5C+which%5C+was%5C+similar%5C+to%5C+other%5C+research%5C+results%5C+of%5C+long%5C-lived%5C+woody%5C+plants%2C%5C+and%5C+reflected%5C+the%5C+genetic%5C+structure%5C+of%5C+its%5C+ancestry%5C+to%5C+same%5C+extent.%5C+There%5C+was%5C+a%5C+high%5C+significant%5C+correlation%5C+between%5C+geographic%5C+distance%5C+and%5C+Nei%E2%80%99s%5C+genetic%5C+distance%5C+%5C%28r%5C+%3D%5C+0.372%2C%5C+P%5C+%3D%5C+0.001%5C%29%5C+of%5C+populations%2C%5C+which%5C+accorded%5C+with%5C+isolation%5C+by%5C+distance%5C+model.%5C+Inferring%5C+from%5C+Bayesian%5C+clustering%5C+of%5C+genotypes%2C%5C+all%5C+individuals%5C+of%5C+C.%5C+taliensis%5C+were%5C+divided%5C+into%5C+two%5C+groups%2C%5C+conflicting%5C+with%5C+the%5C+result%5C+based%5C+on%5C+Nei%E2%80%99s%5C+genetic%5C+distance%5C+and%5C+real%5C+geographic%5C+distribution%2C%5C+which%5C+suggested%5C+there%5C+were%5C+heavy%5C+and%5C+non%5C-random%5C+influences%5C+by%5C+human%5C+practices.%5C+According%5C+to%5C+allelic%5C+richness%2C%5C+there%5C+were%5C+no%5C+significant%5C+differences%5C+%5C%28P%5C+%3E%5C+0.05%5C%29%5C+between%5C+wild%5C+%5C%28AR%5C+%3D%5C+4.651%5C%29%2C%5C+semi%5C-cultivated%5C+%5C%28AR%5C+%3D%5C+5.091%5C%29%5C+and%5C+cultivated%5C+%5C%28AR%5C+%3D%5C+5.132%5C%29%5C+populations%5C+of%5C+C.%5C+taliensis%2C%5C+which%5C+suggested%5C+that%5C+the%5C+genetic%5C+background%5C+of%5C+long%5C-lived%5C+woody%5C+plant%5C+was%5C+not%5C+easy%5C+to%5C+be%5C+changed%2C%5C+and%5C+there%5C+were%5C+moderate%5C+high%5C+gene%5C+flow%5C+between%5C+populations.%5C+However%2C%5C+there%5C+was%5C+a%5C+significant%5C+difference%5C+%5C%28P%5C+%3C%5C+0.05%5C%29%5C+between%5C+wild%5C+%5C%28AR%5C+%3D%5C+5.9%5C%29%5C+and%5C+cultivated%5C+%5C%28AR%5C+%3D%5C+7.1%5C%29%5C+populations%5C+distributed%5C+in%5C+the%5C+same%5C+place%5C+in%5C+Yun%5C+county%2C%5C+Yunnan%5C+province%2C%5C+which%5C+may%5C+result%5C+from%5C+the%5C+hybridization%5C+and%5C+introgression%5C+of%5C+species%5C+in%5C+the%5C+tea%5C+garden%5C+and%5C+anthropogenic%5C+damages%5C+to%5C+the%5C+wild%5C+population.%5C+The%5C+hypothesis%5C+of%5C+hybrid%5C+origin%5C+of%5C+C.%5C+grandibracteata%5C+was%5C+tested%5C+by%5C+morphological%5C+and%5C+microsatellites%5C+analyses.%5C+Compared%5C+with%5C+other%5C+species%2C%5C+the%5C+locules%5C+in%5C+ovary%5C+of%5C+C.%5C+grandibracteata%5C+are%5C+variable%2C%5C+which%5C+showed%5C+a%5C+morphological%5C+intermediate%5C+and%5C+mosaic.%5C+Except%5C+one%5C+private%5C+allele%2C%5C+Ninety%5C-nine%5C+percent%5C+alleles%5C+of%5C+C.%5C+grandibracteata%5C+were%5C+shared%5C+with%5C+these%5C+of%5C+C.%5C+taliensis%5C+and%5C+C.%5C+sinensis%5C+var.%5C+assamica.%5C+And%5C+C.%5C+grandibracteata%5C+was%5C+nested%5C+in%5C+the%5C+cluster%5C+of%5C+C.%5C+taliensis%5C+in%5C+the%5C+UPGMA%5C+tree.%5C+Conclusively%2C%5C+our%5C+results%5C+supported%5C+the%5C+hypothesis%5C+of%5C+hybrid%5C+origin%5C+of%5C+C.%5C+grandibracteata%5C+partly.%5C+The%5C+speciation%5C+of%5C+C.%5C+grandibracteata%5C+was%5C+derived%5C+from%5C+hybridization%5C+and%5C+asymmetrical%5C+introgression%5C+potentially.%5C+It%5C+is%5C+possible%5C+that%5C+C.%5C+taliensis%5C+was%5C+one%5C+of%5C+its%5C+parents%2C%5C+but%5C+it%5C+still%5C+needs%5C+more%5C+evidences%5C+to%5C+prove%5C+that%5C+C.%5C+sinensis%5C+var.%5C+assamica%5C+was%5C+another%5C+parent."},{"jsname":"Chiang Mai University","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AChiang%5C+Mai%5C+University"},{"jsname":"Chinese Academy of Sciences[2013T2S0030]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AChinese%5C+Academy%5C+of%5C+Sciences%5C%5B2013T2S0030%5C%5D"},{"jsname":"Cyatheaceae species, usually called tree ferns, are considered as relicts of a time when dinosaurs were common. In recent several decades, the number of Cyatheaceae plants decreases dramatically. In order to find the reasons and provide directions for protecting these endangered plants, the biological characteristics of Cyatheaceae were surveyed. Using AFLP and cpDNA sequence variations, the genetic diversity and phylogeography of Sphaeropteris brunoniana were also analyzed. Based on these findings, implications for conservation strategies were discussed for this relict tree fern. Main results of the dissertation were summarized as follows, (1) Cyatheaceae plants have extensive distribution in Yunnan, China, and most of them distribute in southeast of Yunnan. In southeast, they usually inhabit margins of evergreen broad-leaved forests or secondary coniferous forests; however, the population update is very different and the age structure is unscientific. The spore of Cyatheaceae is trilete, radially symmetrical, and perinous. The spores of Alsophila species feature a ridged perine and a granular, verrucate or smooth exine. The spores of S. brunoniana are characterized by an incipient granular outermost layer and a verrucate exine. The metaphase chromosome numbers of gametophytes in the three examined species, viz. A. podophylla, A. gigantea and A. austro-yunnanensis, are 69, indicating that they are diploid and do not display variety in chromosome number. The chemical constituents of S. brunoniana are main simple and familiar compounds, such as saccharides, fatty acids and alcohols, and stigmasterols. (2) An unexpectedly high level of nDNA genetic diversity and low cpDNA diversity were detected in S. brunoniana. (3) This study showed that the genetic differentiation among populations within regions was low and between regions was significant. (4) There were several refugia of S. brunoniana in Yunnan during glacial periods. The Hainan populations were likely new colonizations and originated from Southeast Asia. (5) To retain existing genetic diversity, whether in situ or ex situ conservation or collection of germplasm is used, the populations of the two regions should be considered equally. Furthermore, ex situ conservation of this species should be preferably conducted on large populations.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3ACyatheaceae%5C+species%2C%5C+usually%5C+called%5C+tree%5C+ferns%2C%5C+are%5C+considered%5C+as%5C+relicts%5C+of%5C+a%5C+time%5C+when%5C+dinosaurs%5C+were%5C+common.%5C+In%5C+recent%5C+several%5C+decades%2C%5C+the%5C+number%5C+of%5C+Cyatheaceae%5C+plants%5C+decreases%5C+dramatically.%5C+In%5C+order%5C+to%5C+find%5C+the%5C+reasons%5C+and%5C+provide%5C+directions%5C+for%5C+protecting%5C+these%5C+endangered%5C+plants%2C%5C+the%5C+biological%5C+characteristics%5C+of%5C+Cyatheaceae%5C+were%5C+surveyed.%5C+Using%5C+AFLP%5C+and%5C+cpDNA%5C+sequence%5C+variations%2C%5C+the%5C+genetic%5C+diversity%5C+and%5C+phylogeography%5C+of%5C+Sphaeropteris%5C+brunoniana%5C+were%5C+also%5C+analyzed.%5C+Based%5C+on%5C+these%5C+findings%2C%5C+implications%5C+for%5C+conservation%5C+strategies%5C+were%5C+discussed%5C+for%5C+this%5C+relict%5C+tree%5C+fern.%5C+Main%5C+results%5C+of%5C+the%5C+dissertation%5C+were%5C+summarized%5C+as%5C+follows%2C%5C+%5C%281%5C%29%5C+Cyatheaceae%5C+plants%5C+have%5C+extensive%5C+distribution%5C+in%5C+Yunnan%2C%5C+China%2C%5C+and%5C+most%5C+of%5C+them%5C+distribute%5C+in%5C+southeast%5C+of%5C+Yunnan.%5C+In%5C+southeast%2C%5C+they%5C+usually%5C+inhabit%5C+margins%5C+of%5C+evergreen%5C+broad%5C-leaved%5C+forests%5C+or%5C+secondary%5C+coniferous%5C+forests%5C%3B%5C+however%2C%5C+the%5C+population%5C+update%5C+is%5C+very%5C+different%5C+and%5C+the%5C+age%5C+structure%5C+is%5C+unscientific.%5C+The%5C+spore%5C+of%5C+Cyatheaceae%5C+is%5C+trilete%2C%5C+radially%5C+symmetrical%2C%5C+and%5C+perinous.%5C+The%5C+spores%5C+of%5C+Alsophila%5C+species%5C+feature%5C+a%5C+ridged%5C+perine%5C+and%5C+a%5C+granular%2C%5C+verrucate%5C+or%5C+smooth%5C+exine.%5C+The%5C+spores%5C+of%5C+S.%5C+brunoniana%5C+are%5C+characterized%5C+by%5C+an%5C+incipient%5C+granular%5C+outermost%5C+layer%5C+and%5C+a%5C+verrucate%5C+exine.%5C+The%5C+metaphase%5C+chromosome%5C+numbers%5C+of%5C+gametophytes%5C+in%5C+the%5C+three%5C+examined%5C+species%2C%5C+viz.%5C+A.%5C+podophylla%2C%5C+A.%5C+gigantea%5C+and%5C+A.%5C+austro%5C-yunnanensis%2C%5C+are%5C+69%2C%5C+indicating%5C+that%5C+they%5C+are%5C+diploid%5C+and%5C+do%5C+not%5C+display%5C+variety%5C+in%5C+chromosome%5C+number.%5C+The%5C+chemical%5C+constituents%5C+of%5C+S.%5C+brunoniana%5C+are%5C+main%5C+simple%5C+and%5C+familiar%5C+compounds%2C%5C+such%5C+as%5C+saccharides%2C%5C+fatty%5C+acids%5C+and%5C+alcohols%2C%5C+and%5C+stigmasterols.%5C+%5C%282%5C%29%5C+An%5C+unexpectedly%5C+high%5C+level%5C+of%5C+nDNA%5C+genetic%5C+diversity%5C+and%5C+low%5C+cpDNA%5C+diversity%5C+were%5C+detected%5C+in%5C+S.%5C+brunoniana.%5C+%5C%283%5C%29%5C+This%5C+study%5C+showed%5C+that%5C+the%5C+genetic%5C+differentiation%5C+among%5C+populations%5C+within%5C+regions%5C+was%5C+low%5C+and%5C+between%5C+regions%5C+was%5C+significant.%5C+%5C%284%5C%29%5C+There%5C+were%5C+several%5C+refugia%5C+of%5C+S.%5C+brunoniana%5C+in%5C+Yunnan%5C+during%5C+glacial%5C+periods.%5C+The%5C+Hainan%5C+populations%5C+were%5C+likely%5C+new%5C+colonizations%5C+and%5C+originated%5C+from%5C+Southeast%5C+Asia.%5C+%5C%285%5C%29%5C+To%5C+retain%5C+existing%5C+genetic%5C+diversity%2C%5C+whether%5C+in%5C+situ%5C+or%5C+ex%5C+situ%5C+conservation%5C+or%5C+collection%5C+of%5C+germplasm%5C+is%5C+used%2C%5C+the%5C+populations%5C+of%5C+the%5C+two%5C+regions%5C+should%5C+be%5C+considered%5C+equally.%5C+Furthermore%2C%5C+ex%5C+situ%5C+conservation%5C+of%5C+this%5C+species%5C+should%5C+be%5C+preferably%5C+conducted%5C+on%5C+large%5C+populations."},{"jsname":"Cycas micholitzii complex is composed of 5 species: C. micholitzii Dyer, C. bifida (Dyer) K. D. Hill,C. longipetiolula D. Y. Wang, C. debaoensis Y. C. Zhong et C J. Chen, C. multipinnata C J. Chen et S. Y. Yang，and distributed from southwest China to central Vietnam and eastern Laos. Based on sequence data from two maternally inherited cpDNA and one biparentally nuclear DNA fragments, our study revealed the population genetic structure of C. micholitzii complex and explored the potential causes. The evolutionary and demographic histories were investigated. The genetic relationship among species in the complex was also clarified.The results were summarized as follows: 1. Phylogeographic analysis based on chloroplast sequences，We examined chloroplast sequence variation of the atpB-rbcLand psbA-trnHintergenic spacers in 27 populations of C. micholitzii complex, recovering 26 haplotypes. The average within-population diversity (HS = 0.140) was low while total diversity (HT = 0.911) was high. Population differentiation was also high(GST = 0.846, NST = 0.919), indicating significant phylogeographical structure (NST > GST,p < 0.001) and low levels of seed-based gene flow. C. debaoensis (Cycadaceae) is an endangered species restricted to the border of Guangxi and Yunnan province in southwest China. This species has been classified into two types: sand and karst, according to the soil matrix they grow on. We examined chloroplast sequence variation of the cpDNA sequences from 11 populations of this species. Significant population genetic differentiation was detected (GST= 0.684 and FST = 0.74160). There was marked genetic differentiation between populations in the sand and karst regions and no expansion was detected. Climate changes during glacial periods have had significant effects on the current distribution of cycads. The molecular phylogenetic data, together with the geographic distribution of the haplotypes, suggest that C. debaoensis experienced range contraction during glacial periods, and that the current populations are still confined to the original refugia in southwest China which have favorable habitats in glacial period. These results imply that small refugia were maintained in both sand and karst regions during the LGM (last glacial maximum). This species had no postglacial recolonization and only stayed in these refugia up to now. The low within-population diversity of C. debaoensis suggests that there were strong bottleneck events or founder effects within each separate region during the Quaternary climatic oscillations. Relatively high genetic and haplotype diversities were detected in the newly discovered populations, which located at intermediate locality of sand regions and had morphological variation; this is probably the consequence of the admixture of different haplotypes colonizing the area from separate sources. C. micholitzii occurs in the Annan Highlands in central Vietnam near the Laos border. C. bifida occurs in North Vietnam; its distribution extends across the border into adjacent localities in Guangxi and Yunnan in China. For the comparability between them,theywere considered as the same species C. micholitzii by many academicians. The cpDNA sequences from 11 populations showed that these very controversial species, C. micholitzii and C. bifida, is paraphyletic and should belong to the same species C. micholitzii. AMOVA analysis showed that the component of among-population within region/species (76.46%) was unexpectedly larger than the among-species/region component (14.97%), which also indicates that there is no justification for recognizing two species as C. micholitzii and C. bifida. This hypothesis was also supported by the geological data, especially the neotectonic history of the indo-china block, which started to move south since Oligocene and cause the geographic isolation of these two groups. Therefore, the most likely explanation to the phenotypic similarities between these two groups may be the retention of ancestral polymorphisms in the paraphyletic group due to incomplete lineage sorting. Furthermore, the similarities may also be ascribed to pollen-mediated gene flow among geographically proximate populations and/or phenotypic convergence under similar selection schemes in the same region. C.micholitzi had the higest genetic diversity (HT = 0.980,) and genetic differentiation (GST = 0.830, NST = 0.915) among the C. micholitzii complex. The high genetic diversity might be attributed to its long evolutionary history, highly diverse habitats. The ineffective mode of seed dispersal and dramatic neotectonic movement in the distribution range of this species could result in the high genetic differentiation. 2. Phylogeographic analysis based on nuclear ribosomal sequences, We sequenced the nrDNA ITS in all 27 populations sampled, 7 haplotypes were identified, among which C. micholitzii had 6, while C. multipinnata, C. longipetiolula and C. debaoensis shared the remaining one. Compared to chloroplast genes, nuclear genes had higher correlation between genetic and geographical distance, but lower interspecies differentiation (54.42% vs 25.24%). Phylogeographical structure of C. micholitzii and C.bifida based on ITS Variation was consistent with the morphology differentiation. This similar in nuclear gene should be ascribed to pollen-mediated gene flow among geographically proximate populations.Long-distance gene flow over the two groups was clearly interrupted, which brought on the nrDNA genetic differenciation between the geographically isolated groups, to a certain extent affected the morphological variation. 3. Interspecies relationships among Cycas micholitzii complex, We analysed chloroplast sequence variation of the atpB-rbcL and psbA-trnH intergenic spacers in 27 populations sampled of C. micholitzii complex, AMOVA analysis showed that the component of among-species/region component (59.21%). However, phylogenic analysis showed that the haplotypes of C. micholitzii complex couldn`t grouped into four clusters closely corresponding to the narrowly defined C. micholitzi, C. multipinnata, C. debaoensis and C. longipetiolula. We concluded that the conflict may result from several factors: firstly incomplete lineage sorting of C. micholitzii; secondly hybridization/introgression of sympatrically cycads, which would be supported by evidence base on nrDNA ITS sequences; thirdly intramolecular recombination in cpDNA of cycads; eventually the neotectonic movement in the distribution range of this species.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3ACycas%5C+micholitzii%5C+complex%5C+is%5C+composed%5C+of%5C+5%5C+species%5C%3A%5C+C.%5C+micholitzii%5C+Dyer%2C%5C+C.%5C+bifida%5C+%5C%28Dyer%5C%29%5C+K.%5C+D.%5C+Hill%2CC.%5C+longipetiolula%5C+D.%5C+Y.%5C+Wang%2C%5C+C.%5C+debaoensis%5C+Y.%5C+C.%5C+Zhong%5C+et%5C+C%5C+J.%5C+Chen%2C%5C+C.%5C+multipinnata%5C+C%5C+J.%5C+Chen%5C+et%5C+S.%5C+Y.%5C+Yang%EF%BC%8Cand%5C+distributed%5C+from%5C+southwest%5C+China%5C+to%5C+central%5C+Vietnam%5C+and%5C+eastern%5C+Laos.%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+nuclear%5C+DNA%5C+fragments%2C%5C+our%5C+study%5C+revealed%5C+the%5C+population%5C+genetic%5C+structure%5C+of%5C+C.%5C+micholitzii%5C+complex%5C+and%5C+explored%5C+the%5C+potential%5C+causes.%5C+The%5C+evolutionary%5C+and%5C+demographic%5C+histories%5C+were%5C+investigated.%5C+The%5C+genetic%5C+relationship%5C+among%5C+species%5C+in%5C+the%5C+complex%5C+was%5C+also%5C+clarified.The%5C+results%5C+were%5C+summarized%5C+as%5C+follows%5C%3A%5C+1.%5C+Phylogeographic%5C+analysis%5C+based%5C+on%5C+chloroplast%5C+sequences%EF%BC%8CWe%5C+examined%5C+chloroplast%5C+sequence%5C+variation%5C+of%5C+the%5C+atpB%5C-rbcLand%5C+psbA%5C-trnHintergenic%5C+spacers%5C+in%5C+27%5C+populations%5C+of%5C+C.%5C+micholitzii%5C+complex%2C%5C+recovering%5C+26%5C+haplotypes.%5C+The%5C+average%5C+within%5C-population%5C+diversity%5C+%5C%28HS%5C+%3D%5C+0.140%5C%29%5C+was%5C+low%5C+while%5C+total%5C+diversity%5C+%5C%28HT%5C+%3D%5C+0.911%5C%29%5C+was%5C+high.%5C+Population%5C+differentiation%5C+was%5C+also%5C+high%5C%28GST%5C+%3D%5C+0.846%2C%5C+NST%5C+%3D%5C+0.919%5C%29%2C%5C+indicating%5C+significant%5C+phylogeographical%5C+structure%5C+%5C%28NST%5C+%3E%5C+GST%2Cp%5C+%3C%5C+0.001%5C%29%5C+and%5C+low%5C+levels%5C+of%5C+seed%5C-based%5C+gene%5C+flow.%5C+C.%5C+debaoensis%5C+%5C%28Cycadaceae%5C%29%5C+is%5C+an%5C+endangered%5C+species%5C+restricted%5C+to%5C+the%5C+border%5C+of%5C+Guangxi%5C+and%5C+Yunnan%5C+province%5C+in%5C+southwest%5C+China.%5C+This%5C+species%5C+has%5C+been%5C+classified%5C+into%5C+two%5C+types%5C%3A%5C+sand%5C+and%5C+karst%2C%5C+according%5C+to%5C+the%5C+soil%5C+matrix%5C+they%5C+grow%5C+on.%5C+We%5C+examined%5C+chloroplast%5C+sequence%5C+variation%5C+of%5C+the%5C+cpDNA%5C+sequences%5C+from%5C+11%5C+populations%5C+of%5C+this%5C+species.%5C+Significant%5C+population%5C+genetic%5C+differentiation%5C+was%5C+detected%5C+%5C%28GST%3D%5C+0.684%5C+and%5C+FST%5C+%3D%5C+0.74160%5C%29.%5C+There%5C+was%5C+marked%5C+genetic%5C+differentiation%5C+between%5C+populations%5C+in%5C+the%5C+sand%5C+and%5C+karst%5C+regions%5C+and%5C+no%5C+expansion%5C+was%5C+detected.%5C+Climate%5C+changes%5C+during%5C+glacial%5C+periods%5C+have%5C+had%5C+significant%5C+effects%5C+on%5C+the%5C+current%5C+distribution%5C+of%5C+cycads.%5C+The%5C+molecular%5C+phylogenetic%5C+data%2C%5C+together%5C+with%5C+the%5C+geographic%5C+distribution%5C+of%5C+the%5C+haplotypes%2C%5C+suggest%5C+that%5C+C.%5C+debaoensis%5C+experienced%5C+range%5C+contraction%5C+during%5C+glacial%5C+periods%2C%5C+and%5C+that%5C+the%5C+current%5C+populations%5C+are%5C+still%5C+confined%5C+to%5C+the%5C+original%5C+refugia%5C+in%5C+southwest%5C+China%5C+which%5C+have%5C+favorable%5C+habitats%5C+in%5C+glacial%5C+period.%5C+These%5C+results%5C+imply%5C+that%5C+small%5C+refugia%5C+were%5C+maintained%5C+in%5C+both%5C+sand%5C+and%5C+karst%5C+regions%5C+during%5C+the%5C+LGM%5C+%5C%28last%5C+glacial%5C+maximum%5C%29.%5C+This%5C+species%5C+had%5C+no%5C+postglacial%5C+recolonization%5C+and%5C+only%5C+stayed%5C+in%5C+these%5C+refugia%5C+up%5C+to%5C+now.%5C+The%5C+low%5C+within%5C-population%5C+diversity%5C+of%5C+C.%5C+debaoensis%5C+suggests%5C+that%5C+there%5C+were%5C+strong%5C+bottleneck%5C+events%5C+or%5C+founder%5C+effects%5C+within%5C+each%5C+separate%5C+region%5C+during%5C+the%5C+Quaternary%5C+climatic%5C+oscillations.%5C+Relatively%5C+high%5C+genetic%5C+and%5C+haplotype%5C+diversities%5C+were%5C+detected%5C+in%5C+the%5C+newly%5C+discovered%5C+populations%2C%5C+which%5C+located%5C+at%5C+intermediate%5C+locality%5C+of%5C+sand%5C+regions%5C+and%5C+had%5C+morphological%5C+variation%5C%3B%5C+this%5C+is%5C+probably%5C+the%5C+consequence%5C+of%5C+the%5C+admixture%5C+of%5C+different%5C+haplotypes%5C+colonizing%5C+the%5C+area%5C+from%5C+separate%5C+sources.%5C+%5C+C.%5C+micholitzii%5C+occurs%5C+in%5C+the%5C+Annan%5C+Highlands%5C+in%5C+central%5C+Vietnam%5C+near%5C+the%5C+Laos%5C+border.%5C+C.%5C+bifida%5C+occurs%5C+in%5C+North%5C+Vietnam%5C%3B%5C+its%5C+distribution%5C+extends%5C+across%5C+the%5C+border%5C+into%5C+adjacent%5C+localities%5C+in%5C+Guangxi%5C+and%5C+Yunnan%5C+in%5C+China.%5C+For%5C+the%5C+comparability%5C+between%5C+them%2Ctheywere%5C+considered%5C+as%5C+the%5C+same%5C+species%5C+C.%5C+micholitzii%5C+by%5C+many%5C+academicians.%5C+The%5C+cpDNA%5C+sequences%5C+from%5C+11%5C+po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study can reveal important biological features of plants and answers to a certain degree in phylogeny and distribution of genetic materials and so forth. By hard working of cytologists, chromosome data of plants have been increased to a great abundance, but yet disorderly distributed in different magazines, which made researches based on the whole chromosome data of one taxon rarely launched. Scientific databases have become increasingly indispensable as researching data growing daily. As Cytological studies are booming in China, in order to fill the absence of digital and statistical data of plant chromosome researches and chromosome atlas, we started to develop a Chinese Seed Plants Chromosome Database, aiming to construct a database and start to record published chromosome data of Chinese seed plants. Based on this database, we chose the part of gymnosperms and gave a discussion to the features of its chromosomes’ evolution and variation. Cytological experiments have been applied to some important phyto-groups for phylogeny research and germplasm identification.Part I: The Chinese Seed Plants Chromosome Database and Discussion on the features of Gymnosperms chromosomes，1 The Chinese Seed Plants Chromosome Database，The frame of database was constructed by Microsoft Access 2003. 19 items of data were included in, they are: Chinese and Latin names of family, genus and species; plant pictures, mitosis metaphase and karyotype figures; morphological characteristics and distributions of the plant; chromosome numbers and basic numbers; karyotype formula; karyotype description; origin of the plant material; literature and the source of photos. In this database, data can be checked and shared easily by extracted out in species sorted interface or family sorted interface. 120 species in 29 genera and 10 families of Gymnospers have been collected and input to the database. In Angiosperms, 61 species in 10 genera of family Magnoliaceae and 80 species in 3 genera of family Theaceae have been collected and input to the database.2 Discussion on the features of evolution and variation of Gymnosperms chromosomes，By data collection of the database, we analyzed chromosome features of the group Gymnosperm. Plants of Gymnosperm had been through a long historical evolution on earth, fossil records of which originated from the late Devonian period. Once an authoritative and major classification level in the plant kingdom, most Gymnosperms have been extinct unless conifers, cycads, Ginkgo and Getales. Three main features of Gymnosperm chromosomes are: relatively large chromosome, which can be recognized from figures in the database; constant chromosome numbers, in most families of Gymnosperm the basic chromosome number keeps a certain value; comparatively low variation, karyotype under family level differs a little. The variation of chromosomes in Gymnosperm is dominated by Robertsonian changes. Contrary to common variation type in Angiosperms, the variation from high unsymmetric karyotype to low unsymmetric karyotype was found in existence in Gymnosperm.Part II: cytology research on some important phyto-groups，3 Karyomorphology of three species in the order Huerteales and their phylogenetic implications，The karyomorphology of three species in Dipentodon (Dipentodontaceae), Perrottetia (Celastraceae), and Tapiscia (Tapisciaceae), namely Dipentodon sinicus, Perrottetia racemosa, and Tapiscia sinensis, was investigated in the study. Recent molecular research has discovered close relationships among these three genera, which has led to the establishment of the order Huerteales with Perrottetia being placed in Dipentodontaceae. Herein we report the chromosome numbers of D. sinicus and P. racemosa for the first time, and present their karyotype formulas as 2n = 34 = 22sm + 12st (D. sinicus), 2n = 20 = 11m + 9sm (P. racemosa), and 2n = 30 = 22m(2SAT) + 8sm (T. sinensis). Asymmetry of their karyotypes is categorized to be Type 3B in D. sinicus, Type 2A in P. racemosa, and Type 2A in T. sinensis. Each of the species shows special cytological features. Compared with Perrottetia, Dipentodon has a different basic chromosome number, a higher karyotype asymmetry, and different karyomorphology of its interphase nuclei, mitotic prophase, and metaphase. Thus, on the basis of these results, we have reservations regarding the suggestion of placing Dipentodon and Perrottetia together in the family Dipentodontaceae.4 Genomic analyses of intergeneric hybrids between Michelia crassipes and M. calcicola by GISH，Genomic in situ hybridization (GISH) is becoming the method of choice for identifying parental chromosomes in interspecific hybrids. Interspecific F1 hybrid between Michelia crassipes and M. calcicola, tow highly ornamental species in Michelia of Magnolicaceae, has been analized by double-colored GISH with its parents’ genome as the probe. Research gave the results that the chromosome number of the F1 hybrid is 2n=38 as the same of species in Michelia and other genera in Magnoliaceae, the basic chromosome is x=19, the karyotype formula is 2n=38=32m+6sm, and the asymmetry of karyotype is 1B type. Based on chromosome data of Michelia in our database, the karyotype of this genus is featured mostly by metacentric chromosomes and submetacentric chromosomes. In Mechelia, the variation range of submetacentric chromosomes is 4 to 18 and of the karyotype asymmetry is 1A to 2B type. Both the karyotype and karyotype asymmetry type of F1 hybrid is among the variation range of Michelia. The figure of GISH showed that all the 38 chromosomes of F1 hybrid have crossing parental signals, and signal on the no.1 and no.7 chromosome showed differences, which proved that both the parental genome have been transmitted to and recombinated in F1 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the rapid uplift of the Himalaya, the reorganization of the major river drainages was primarily caused by river capture events，e.g. those of the Jinshajiang River (comprising the Upper, Middle and Lower Jinshajiang) and its tributaries (Yalongjiang, Daduhe, Jialingjiang), the Nujiang, the Lancangjiang, and the Honghe. We selected Terminalia franchetii var. franchetii and T. franchetii var. intricata in the Sino-Himalayan region to study the relationship with Honghe diversion events. The distribution of this species is predicted to have retained genetic signatures of past hydrological landscape structures. The major result as flowing:1. Chloroplast phylogeography of T. franchetii based on haplotype analysis，Based on a range-wide sampling comprising 28 populations and 258 individuals, and using chloroplast DNA sequences (trnL-trnF, petL-psbE), we detected 12 haplotypes. Terminalia franchetii was found to harbour high haplotype diversity (hT = 0.784) but low average within-population diversity (hS = 0.124). The analysis of genetic structure using SAMOVA showed that the number of population groups equaled five, and all the haplotypes can be divided into five groups. Group B and C identified exhibited a disjunctive distribution of dominant haplotypes between northern and southern valleys, corresponding to the geography of past rather than modern drainage systems.Mismatch distribution (multimodal curve) and neutral tests provided no evidence of recent demographic population growth. We suggest that the modern disjunctive distribution of T. franchetii, and associated patterns of cpDNA haplotype variation, result from vicariance caused by several historical river separation and capture events. By assuming a common mutation rate of the cpDNA-IGS regions, our inferred timings of these events (0.82-4.39 Mya) broadly agrees with both previous geological and molecular estimated time of drainage rearrangements in this region. So we conclude that there were several historical vicariance events play a major role for the distribution of T. franchetii in this region.2. Genetic diversity and structure of T. franchetii var. franchetii based on AFLP analysis，We determined the genotype of 251 individuals of T. franchetii var. franchetii from 21 populations using amplified fragment length polymorphism (AFLP), for our aim is only investigated the relationship between the modern distribution of T. franchetii and geological changes in drainage patterns. The overall estimate of genetic structure (Gst) was 0.249, indicating that clear genetic differentiation existed among the populations. Estimates of gene flow (Nm = 0.754) between populations based on the Gst value revealed that the number of migrants per generation is not frequently.Using Neighbor-Joining tree, Principal Coordinates Analysis, STRUCTURE and network methods, Analyses of AFLP markers identified two main population groups (I and II) and four subgroups (A – D) of T. franchetii. Genetic diversity was lower in Group I than in Group II. The results show that Groups I and II probably once occupied continuous areas respectively along ancient drainage systems and there were several historical separation and capture events that can account for the distribution of T. franchetii in this region. After all，these are good examples of the way in which historical events can change a species’ distribution from continuous to fragmented (Jinshajiang/ Yalongjiang and Honghe), and a disjunct distribution to a continuous one (Upper/Lower Jinshajiang and Yalongjiang). The results provide new insights into the phylogeographic pattern of plants in southwest China.3. Relationships between T. franchetii var. franchetii and T. franchetii var. intricata ，While T. franchetii var. Franchetii and var. intricata slightly differ in overall size and leaf hairiness, these taxa did not exhibit reciprocal monophyly. As results show, the genetic difference between the two varieties is much smaller than that within var. franchetii (Salween population vs. other populationsof this variety). It is also revealed in a phylogenetic analysis of ITS region of Combretoideae. The habitats of var. franchetii and var. intricata have obviously difference. Thus, the differences between the two varieties in overall size and leaf hairiness might reflect different phenotypic responses to environmental changes and the divergent environmental niche spaces they occupy. Based on the reasoning above, we agree with Flora of China that “T. intricata” represents a variety of T. franchetii rather than a separate species.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AFollowing%5C+the%5C+rapid%5C+uplift%5C+of%5C+the%5C+Himalaya%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+capture%5C+events%EF%BC%8Ce.g.%5C+those%5C+of%5C+the%5C+Jinshajiang%5C+River%5C+%5C%28comprising%5C+the%5C+Upper%2C%5C+Middle%5C+and%5C+Lower%5C+Jinshajiang%5C%29%5C+and%5C+its%5C+tributaries%5C+%5C%28Yalongjiang%2C%5C+Daduhe%2C%5C+Jialingjiang%5C%29%2C%5C+the%5C+Nujiang%2C%5C+the%5C+Lancangjiang%2C%5C+and%5C+the%5C+Honghe.%5C+We%5C+selected%5C+Terminalia%5C+franchetii%5C+var.%5C+franchetii%5C+and%5C+T.%5C+franchetii%5C+var.%5C+intricata%5C+in%5C+the%5C+Sino%5C-Himalayan%5C+region%5C+to%5C+study%5C+the%5C+relationship%5C+with%5C+Honghe%5C+diversion%5C+events.%5C+The%5C+distribution%5C+of%5C+this%5C+species%5C+is%5C+predicted%5C+to%5C+have%5C+retained%5C+genetic%5C+signatures%5C+of%5C+past%5C+hydrological%5C+landscape%5C+structures.%5C+The%5C+major%5C+result%5C+as%5C+flowing%5C%3A1.%5C+Chloroplast%5C+phylogeography%5C+of%5C+T.%5C+franchetii%5C+based%5C+on%5C+haplotype%5C+analysis%EF%BC%8CBased%5C+on%5C+a%5C+range%5C-wide%5C+sampling%5C+comprising%5C+28%5C+populations%5C+and%5C+258%5C+individuals%2C%5C+and%5C+using%5C+chloroplast%5C+DNA%5C+sequences%5C+%5C%28trnL%5C-trnF%2C%5C+petL%5C-psbE%5C%29%2C%5C+we%5C+detected%5C+12%5C+haplotypes.%5C+Terminalia%5C+franchetii%5C+was%5C+found%5C+to%5C+harbour%5C+high%5C+haplotype%5C+diversity%5C+%5C%28hT%5C+%3D%5C+0.784%5C%29%5C+but%5C+low%5C+average%5C+within%5C-population%5C+diversity%5C+%5C%28hS%5C+%3D%5C+0.124%5C%29.%5C+The%5C+analysis%5C+of%5C+genetic%5C+structure%5C+using%5C+SAMOVA%5C+showed%5C+that%5C+the%5C+number%5C+of%5C+population%5C+groups%5C+equaled%5C+five%2C%5C+and%5C+all%5C+the%5C+haplotypes%5C+can%5C+be%5C+divided%5C+into%5C+five%5C+groups.%5C+Group%5C+B%5C+and%5C+C%5C+identified%5C+exhibited%5C+a%5C+disjunctive%5C+distribution%5C+of%5C+dominant%5C+haplotypes%5C+between%5C+northern%5C+and%5C+southern%5C+valleys%2C%5C+corresponding%5C+to%5C+the%5C+geography%5C+of%5C+past%5C+rather%5C+than%5C+modern%5C+drainage%5C+systems.Mismatch%5C+distribution%5C+%5C%28multimodal%5C+curve%5C%29%5C+and%5C+neutral%5C+tests%5C+provided%5C+no%5C+evidence%5C+of%5C+recent%5C+demographic%5C+population%5C+growth.%5C+We%5C+suggest%5C+that%5C+the%5C+modern%5C+disjunctive%5C+distribution%5C+of%5C+T.%5C+franchetii%2C%5C+and%5C+associated%5C+patterns%5C+of%5C+cpDNA%5C+haplotype%5C+variation%2C%5C+result%5C+from%5C+vicariance%5C+caused%5C+by%5C+several%5C+historical%5C+river%5C+separation%5C+and%5C+capture%5C+events.%5C+By%5C+assuming%5C+a%5C+common%5C+mutation%5C+rate%5C+of%5C+the%5C+cpDNA%5C-IGS%5C+regions%2C%5C+our%5C+inferred%5C+timings%5C+of%5C+these%5C+events%5C+%5C%280.82%5C-4.39%5C+Mya%5C%29%5C+broadly%5C+agrees%5C+with%5C+both%5C+previous%5C+geological%5C+and%5C+molecular%5C+estimated%5C+time%5C+of%5C+drainage%5C+rearrangements%5C+in%5C+this%5C+region.%5C+So%5C+we%5C+conclude%5C+that%5C+there%5C+were%5C+several%5C+historical%5C+vicariance%5C+events%5C+play%5C+a%5C+major%5C+role%5C+for%5C+the%5C+distribution%5C+of%5C+T.%5C+franchetii%5C+in%5C+this%5C+region.2.%5C+Genetic%5C+diversity%5C+and%5C+structure%5C+of%5C+T.%5C+franchetii%5C+var.%5C+franchetii%5C+based%5C+on%5C+AFLP%5C+analysis%EF%BC%8CWe%5C+determined%5C+the%5C+genotype%5C+of%5C+251%5C+individuals%5C+of%5C+T.%5C+franchetii%5C+var.%5C+franchetii%5C+from%5C+21%5C+populations%5C+using%5C+amplified%5C+fragment%5C+length%5C+polymorphism%5C+%5C%28AFLP%5C%29%2C%5C+for%5C+our%5C+aim%5C+is%5C+only%5C+investigated%5C+the%5C+relationship%5C+between%5C+the%5C+modern%5C+distribution%5C+of%5C+T.%5C+franchetii%5C+and%5C+geological%5C+changes%5C+in%5C+drainage%5C+patterns.%5C+The%5C+overall%5C+estimate%5C+of%5C+genetic%5C+structure%5C+%5C%28Gst%5C%29%5C+was%5C+0.249%2C%5C+indicating%5C+that%5C+clear%5C+genetic%5C+differentiation%5C+existed%5C+among%5C+the%5C+populations.%5C+Estimates%5C+of%5C+gene%5C+flow%5C+%5C%28Nm%5C+%3D%5C+0.754%5C%29%5C+between%5C+populations%5C+based%5C+on%5C+the%5C+Gst%5C+value%5C+revealed%5C+that%5C+the%5C+number%5C+of%5C+migrants%5C+per%5C+generation%5C+is%5C+not%5C+frequently.Using%5C+Neighbor%5C-Joining%5C+tree%2C%5C+Principal%5C+Coordinates%5C+Analysis%2C%5C+STRUCTURE%5C+and%5C+network%5C+methods%2C%5C+Analyses%5C+of%5C+AFLP%5C+markers%5C+identified%5C+two%5C+main%5C+population%5C+groups%5C+%5C%28I%5C+and%5C+II%5C%29%5C+and%5C+four%5C+subgroups%5C+%5C%28A%5C+%E2%80%93%5C+D%5C%29%5C+of%5C+T.%5C+franchetii.%5C+Genetic%5C+diversity%5C+was%5C+lower%5C+in%5C+Group%5C+I%5C+than%5C+in%5C+Group%5C+II.%5C+The%5C+results%5C+show%5C+that%5C+Groups%5C+I%5C+and%5C+II%5C+probably%5C+once%5C+occupied%5C+continuous%5C+areas%5C+respectively%5C+along%5C+ancient%5C+drainage%5C+systems%5C+and%5C+there%5C+were%5C+several%5C+historical%5C+separation%5C+and%5C+capture%5C+events%5C+that%5C+can%5C+acc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of the Royal Botanic Gardens Victoria","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AFriends%5C+of%5C+the%5C+Royal%5C+Botanic%5C+Gardens%5C+Victoria"},{"jsname":"Fundamental Research Funds for the Central Universities[YX2013-412018BLCB08]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AFundamental%5C+Research%5C+Funds%5C+for%5C+the%5C+Central%5C+Universities%5C%5BYX2013%5C-412018BLCB08%5C%5D"},{"jsname":"Guizhou Natural Science Foundation[Qiankehe LH (2016) 7206]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AGuizhou%5C+Natural%5C+Science%5C+Foundation%5C%5BQiankehe%5C+LH%5C+%5C%282016%5C%29%5C+7206%5C%5D"},{"jsname":"How has natural selection determined the evolution of gene regulation by acting on major regulatory factors? This question has been attractive to many evolutionary biologists for a long time. MicroRNAs (miRNAs) are endogenous posttranscriptional repressors and play essential roles in diverse biological processes in plants. To understand how natural selection has targeted on the entire lay of miRNA regulatory modules during flower development, we resequenced 31 miRNA target sites involved in flower development from five rice populations. We found that purifying selection serves as a major evolutionary force to act on the conserved miRNA binding sites, leading to the globally reduced genetic variation in highly conserved miRNA binding sequences within the entire rice samples. Conversely, positive selection allows variations at nonconserved miRNA binding sites and acts on them in a population-specific behaviour. Further analysis revealed that the polymorphisms within target sites may serve as raw materials for diverse functions of miRNAs by means of the destabilization of duplex, abolishment of existing target sites, and creation of novel ones. Together, the above-mentioned results indicate that variations at conserved binding sites are likely deleterious during rice flower development, whereas variants at nonconserved binding sites may be conductive to flower development-related phenotypic diversities and rice population adaption to variable environmental conditions as well. To further assess functional effects and evolutionary significance of variable alleles at the target genes, we reported the detailed characterization of the haplotype and linkage disequilibrium (LD) patterns of the entire target gene (LOC_Os01g18850，SPL 1) and the 1.4 Mb flanking regions in three rice populations, namely japonica, indica and O. rufipogon. The genetic profile of SNPs at target site and its flanking regions revealed high haplotype frequency, low haplotype diversity and strong LD in two cultivatedricepopulations. By contrast, we observed the opposite phenomena in O. rufipogon. Using the long-range haplotype (LRT) test, we found strong evidence of recent positive selection for SNP 3C/T alleles at target site in the combined O. sativa. Comparsion between the two rice subpopulations indicated that the major haplotype mh 2 containing SNP 3C accounts for half of all haplotypes in indica, while mh 3 containing SNP 3T is 91% in japonica. Moreover, the extent of LD is stronger in japonica than that in inidca. These differences suggest that independent evolutionary events may have occurred in target sequences of two cultivated rice populations and stronger positive selection acted on japonica. Next, we examined geographic distribution of polymorphic variants at target sites. We found that the major alleles SNP 3T and tightly linked SNP 4A in japonica appear to be associated with the adaption to the northern climates during rice flower development.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AHow%5C+has%5C+natural%5C+selection%5C+determined%5C+the%5C+evolution%5C+of%5C+gene%5C+regulation%5C+by%5C+acting%5C+on%5C+major%5C+regulatory%5C+factors%5C%3F%5C+This%5C+question%5C+has%5C+been%5C+attractive%5C+to%5C+many%5C+evolutionary%5C+biologists%5C+for%5C+a%5C+long%5C+time.%5C+MicroRNAs%5C+%5C%28miRNAs%5C%29%5C+are%5C+endogenous%5C+posttranscriptional%5C+repressors%5C+and%5C+play%5C+essential%5C+roles%5C+in%5C+diverse%5C+biological%5C+processes%5C+in%5C+plants.%5C+To%5C+understand%5C+how%5C+natural%5C+selection%5C+has%5C+targeted%5C+on%5C+the%5C+entire%5C+lay%5C+of%5C+miRNA%5C+regulatory%5C+modules%5C+during%5C+flower%5C+development%2C%5C+we%5C+resequenced%5C+31%5C+miRNA%5C+target%5C+sites%5C+involved%5C+in%5C+flower%5C+development%5C+from%5C+five%5C+rice%5C+populations.%5C+We%5C+found%5C+that%5C+purifying%5C+selection%5C+serves%5C+as%5C+a%5C+major%5C+evolutionary%5C+force%5C+to%5C+act%5C+on%5C+the%5C+conserved%5C+miRNA%5C+binding%5C+sites%2C%5C+leading%5C+to%5C+the%5C+globally%5C+reduced%5C+genetic%5C+variation%5C+in%5C+highly%5C+conserved%5C+miRNA%5C+binding%5C+sequences%5C+within%5C+the%5C+entire%5C+rice%5C+samples.%5C+Conversely%2C%5C+positive%5C+selection%5C+allows%5C+variations%5C+at%5C+nonconserved%5C+miRNA%5C+binding%5C+sites%5C+and%5C+acts%5C+on%5C+them%5C+in%5C+a%5C+population%5C-specific%5C+behaviour.%5C+Further%5C+analysis%5C+revealed%5C+that%5C+the%5C+polymorphisms%5C+within%5C+target%5C+sites%5C+may%5C+serve%5C+as%5C+raw%5C+materials%5C+for%5C+diverse%5C+functions%5C+of%5C+miRNAs%5C+by%5C+means%5C+of%5C+the%5C+destabilization%5C+of%5C+duplex%2C%5C+abolishment%5C+of%5C+existing%5C+target%5C+sites%2C%5C+and%5C+creation%5C+of%5C+novel%5C+ones.%5C+Together%2C%5C+the%5C+above%5C-mentioned%5C+results%5C+indicate%5C+that%5C+variations%5C+at%5C+conserved%5C+binding%5C+sites%5C+are%5C+likely%5C+deleterious%5C+during%5C+rice%5C+flower%5C+development%2C%5C+whereas%5C+variants%5C+at%5C+nonconserved%5C+binding%5C+sites%5C+may%5C+be%5C+conductive%5C+to%5C+flower%5C+development%5C-related%5C+phenotypic%5C+diversities%5C+and%5C+rice%5C+population%5C+adaption%5C+to%5C+variable%5C+environmental%5C+conditions%5C+as%5C+well.%5C+To%5C+further%5C+assess%5C+functional%5C+effects%5C+and%5C+evolutionary%5C+significance%5C+of%5C+variable%5C+alleles%5C+at%5C+the%5C+target%5C+genes%2C%5C+we%5C+reported%5C+the%5C+detailed%5C+characterization%5C+of%5C+the%5C+haplotype%5C+and%5C+linkage%5C+disequilibrium%5C+%5C%28LD%5C%29%5C+patterns%5C+of%5C+the%5C+entire%5C+target%5C+gene%5C+%5C%28LOC_Os01g18850%EF%BC%8CSPL%5C+1%5C%29%5C+and%5C+the%5C+1.4%5C+Mb%5C+flanking%5C+regions%5C+in%5C+three%5C+rice%5C+populations%2C%5C+namely%5C+japonica%2C%5C+indica%5C+and%5C+O.%5C+rufipogon.%5C+The%5C+genetic%5C+profile%5C+of%5C+SNPs%5C+at%5C+target%5C+site%5C+and%5C+its%5C+flanking%5C+regions%5C+revealed%5C+high%5C+haplotype%5C+frequency%2C%5C+low%5C+haplotype%5C+diversity%5C+and%5C+strong%5C+LD%5C+in%5C+two%5C+cultivatedricepopulations.%5C+By%5C+contrast%2C%5C+we%5C+observed%5C+the%5C+opposite%5C+phenomena%5C+in%5C+O.%5C+rufipogon.%5C+Using%5C+the%5C+long%5C-range%5C+haplotype%5C+%5C%28LRT%5C%29%5C+test%2C%5C+we%5C+found%5C+strong%5C+evidence%5C+of%5C+recent%5C+positive%5C+selection%5C+for%5C+SNP%5C+3C%5C%2FT%5C+alleles%5C+at%5C+target%5C+site%5C+in%5C+the%5C+combined%5C+O.%5C+sativa.%5C+Comparsion%5C+between%5C+the%5C+two%5C+rice%5C+subpopulations%5C+indicated%5C+that%5C+the%5C+major%5C+haplotype%5C+mh%5C+2%5C+containing%5C+SNP%5C+3C%5C+accounts%5C+for%5C+half%5C+of%5C+all%5C+haplotypes%5C+in%5C+indica%2C%5C+while%5C+mh%5C+3%5C+containing%5C+SNP%5C+3T%5C+is%5C+91%25%5C+in%5C+japonica.%5C+Moreover%2C%5C+the%5C+extent%5C+of%5C+LD%5C+is%5C+stronger%5C+in%5C+japonica%5C+than%5C+that%5C+in%5C+inidca.%5C+These%5C+differences%5C+suggest%5C+that%5C+independent%5C+evolutionary%5C+events%5C+may%5C+have%5C+occurred%5C+in%5C+target%5C+sequences%5C+of%5C+two%5C+cultivated%5C+rice%5C+populations%5C+and%5C+stronger%5C+positive%5C+selection%5C+acted%5C+on%5C+japonica.%5C+Next%2C%5C+we%5C+examined%5C+geographic%5C+distribution%5C+of%5C+polymorphic%5C+variants%5C+at%5C+target%5C+sites.%5C+We%5C+found%5C+that%5C+the%5C+major%5C+alleles%5C+SNP%5C+3T%5C+and%5C+tightly%5C+linked%5C+SNP%5C+4A%5C+in%5C+japonica%5C+appear%5C+to%5C+be%5C+associated%5C+with%5C+the%5C+adaption%5C+to%5C+the%5C+northern%5C+climates%5C+during%5C+rice%5C+flower%5C+development."},{"jsname":"In the present study, we focused on “Pterygiella complex”, included Pterygiella Oliver, Xizangia D.Y. Hong, Phtheirospermum Bunge ex Fischer & C.A. Meyer, and Pseudobartsia D.Y. Hong, which is endemic to Eastern Asia. Based on chloroplast and nuclear sequences, we explored their phylogeny relationships within Orobanchaceae, the species relations within Pterygiella, and fruit and seed morphology of traditional tribe Rhinantheae. The phylogeny of “Pterygiella complex” was reconstructed based on nuclear and chloroplast sequences within the family Orobanchaceae. The genera relationship within the complex was reconstructed based on chloroplast sequences of atpB-rbcL, atpH-I, psbA-trnH, rpl16, trnL-F and trnS-G. The results showed that “Pterygiella complex” was not a natural group and could be divided into two different clades. Clade I included most taxa, e.g. Pterygiella, Xizangia, Pseudobartsia, Phtheirospermum (exclude P. japonicum). The species of this clade were endemic to East-Himalaya and Hengduan Mountains region. Clade II included Phtheirospermum japonicum (Thunberg) Kanitz, which was a heterogeneous member in genus Phtheirospermum and should be treated as a new monotypic genus. The results supported that Pterygiella bartschioides Hand.-Mazz. and Phtheirospermum glandulosum Benth. should be elevated to genus level as Xizangia and Pseudobartsia, respectively.Furthermore, we focused on the genus Pterygiella to explore the species’ circumscription by molecular phylogeny, DNA barcodes and morphological studies. The results suggested that Pterygiella should divide into three clades. P. duclouxii was divided into clade I and clade II, and P. nigrescens was included the clade I of these P. duclouxii taxa, with which it shares eglandular hairs on the stem. Clade III included P. suffruticosa and P. cylindrica, while the level of inter- and intra-species variation in two species did not support their distinction. Therefore, P. suffruticosa should move into or considered as a variety of P. cylindrica. The form of stem, leaf veins and the indumentum of stems are key traits for circumscribing the species within the genus. By comparing the effectiveness with core DNA barcodes, ITS-2 can be used as suitable DNA barcode in the genus Pterygiella.Fruit and seed characteristics of 49 species in 21 genera of the tribe Rhinantheae and 9 species in 9 genera of Orobachaceae were examined. 25 characters were selected and analyzed by principal component analysis for discovering the systematic significances. The results suggested four main types and six subtypes were distinguished based on gross seed coat appearance, inner tangential wall and thickenings of radial wall. Fruit and seed data reflect the close relationships within “Pterygiella complex”. While, Xizangia was distinctly different from Pterygiella. Phtheirospermum tenuisectum was more similar to the member of section minutisepala within the genus Phtheiroseprmum. Phtheirospermum japonicum was heterogeneous within the genus Phtheirospermum. On the whole, fruit and seed data supported Xizangia and Pseudobartsia as a genus rank and Phtheirospermum japonicum was a heterogeneous member in Phtheirospermum","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AIn%5C+the%5C+present%5C+study%2C%5C+we%5C+focused%5C+on%5C+%E2%80%9CPterygiella%5C+complex%E2%80%9D%2C%5C+included%5C+Pterygiella%5C+Oliver%2C%5C+Xizangia%5C+D.Y.%5C+Hong%2C%5C+Phtheirospermum%5C+Bunge%5C+ex%5C+Fischer%5C+%5C%26%5C+C.A.%5C+Meyer%2C%5C+and%5C+Pseudobartsia%5C+D.Y.%5C+Hong%2C%5C+which%5C+is%5C+endemic%5C+to%5C+Eastern%5C+Asia.%5C+Based%5C+on%5C+chloroplast%5C+and%5C+nuclear%5C+sequences%2C%5C+we%5C+explored%5C+their%5C+phylogeny%5C+relationships%5C+within%5C+Orobanchaceae%2C%5C+the%5C+species%5C+relations%5C+within%5C+Pterygiella%2C%5C+and%5C+fruit%5C+and%5C+seed%5C+morphology%5C+of%5C+traditional%5C+tribe%5C+Rhinantheae.%5C+The%5C+phylogeny%5C+of%5C+%E2%80%9CPterygiella%5C+complex%E2%80%9D%5C+was%5C+reconstructed%5C+based%5C+on%5C+nuclear%5C+and%5C+chloroplast%5C+sequences%5C+within%5C+the%5C+family%5C+Orobanchaceae.%5C+The%5C+genera%5C+relationship%5C+within%5C+the%5C+complex%5C+was%5C+reconstructed%5C+based%5C+on%5C+chloroplast%5C+sequences%5C+of%5C+atpB%5C-rbcL%2C%5C+atpH%5C-I%2C%5C+psbA%5C-trnH%2C%5C+rpl16%2C%5C+trnL%5C-F%5C+and%5C+trnS%5C-G.%5C+The%5C+results%5C+showed%5C+that%5C+%E2%80%9CPterygiella%5C+complex%E2%80%9D%5C+was%5C+not%5C+a%5C+natural%5C+group%5C+and%5C+could%5C+be%5C+divided%5C+into%5C+two%5C+different%5C+clades.%5C+Clade%5C+I%5C+included%5C+most%5C+taxa%2C%5C+e.g.%5C+Pterygiella%2C%5C+Xizangia%2C%5C+Pseudobartsia%2C%5C+Phtheirospermum%5C+%5C%28exclude%5C+P.%5C+japonicum%5C%29.%5C+The%5C+species%5C+of%5C+this%5C+clade%5C+were%5C+endemic%5C+to%5C+East%5C-Himalaya%5C+and%5C+Hengduan%5C+Mountains%5C+region.%5C+Clade%5C+II%5C+included%5C+Phtheirospermum%5C+japonicum%5C+%5C%28Thunberg%5C%29%5C+Kanitz%2C%5C+which%5C+was%5C+a%5C+heterogeneous%5C+member%5C+in%5C+genus%5C+Phtheirospermum%5C+and%5C+should%5C+be%5C+treated%5C+as%5C+a%5C+new%5C+monotypic%5C+genus.%5C+The%5C+results%5C+supported%5C+that%5C+Pterygiella%5C+bartschioides%5C+Hand.%5C-Mazz.%5C+and%5C+Phtheirospermum%5C+glandulosum%5C+Benth.%5C+should%5C+be%5C+elevated%5C+to%5C+genus%5C+level%5C+as%5C+Xizangia%5C+and%5C+Pseudobartsia%2C%5C+respectively.Furthermore%2C%5C+we%5C+focused%5C+on%5C+the%5C+genus%5C+Pterygiella%5C+to%5C+explore%5C+the%5C+species%E2%80%99%5C+circumscription%5C+by%5C+molecular%5C+phylogeny%2C%5C+DNA%5C+barcodes%5C+and%5C+morphological%5C+studies.%5C+The%5C+results%5C+suggested%5C+that%5C+Pterygiella%5C+should%5C+divide%5C+into%5C+three%5C+clades.%5C+P.%5C+duclouxii%5C+was%5C+divided%5C+into%5C+clade%5C+I%5C+and%5C+clade%5C+II%2C%5C+and%5C+P.%5C+nigrescens%5C+was%5C+included%5C+the%5C+clade%5C+I%5C+of%5C+these%5C+P.%5C+duclouxii%5C+taxa%2C%5C+with%5C+which%5C+it%5C+shares%5C+eglandular%5C+hairs%5C+on%5C+the%5C+stem.%5C+Clade%5C+III%5C+included%5C+P.%5C+suffruticosa%5C+and%5C+P.%5C+cylindrica%2C%5C+while%5C+the%5C+level%5C+of%5C+inter%5C-%5C+and%5C+intra%5C-species%5C+variation%5C+in%5C+two%5C+species%5C+did%5C+not%5C+support%5C+their%5C+distinction.%5C+Therefore%2C%5C+P.%5C+suffruticosa%5C+should%5C+move%5C+into%5C+or%5C+considered%5C+as%5C+a%5C+variety%5C+of%5C+P.%5C+cylindrica.%5C+The%5C+form%5C+of%5C+stem%2C%5C+leaf%5C+veins%5C+and%5C+the%5C+indumentum%5C+of%5C+stems%5C+are%5C+key%5C+traits%5C+for%5C+circumscribing%5C+the%5C+species%5C+within%5C+the%5C+genus.%5C+By%5C+comparing%5C+the%5C+effectiveness%5C+with%5C+core%5C+DNA%5C+barcodes%2C%5C+ITS%5C-2%5C+can%5C+be%5C+used%5C+as%5C+suitable%5C+DNA%5C+barcode%5C+in%5C+the%5C+genus%5C+Pterygiella.Fruit%5C+and%5C+seed%5C+characteristics%5C+of%5C+49%5C+species%5C+in%5C+21%5C+genera%5C+of%5C+the%5C+tribe%5C+Rhinantheae%5C+and%5C+9%5C+species%5C+in%5C+9%5C+genera%5C+of%5C+Orobachaceae%5C+were%5C+examined.%5C+25%5C+characters%5C+were%5C+selected%5C+and%5C+analyzed%5C+by%5C+principal%5C+component%5C+analysis%5C+for%5C+discovering%5C+the%5C+systematic%5C+significances.%5C+The%5C+results%5C+suggested%5C+four%5C+main%5C+types%5C+and%5C+six%5C+subtypes%5C+were%5C+distinguished%5C+based%5C+on%5C+gross%5C+seed%5C+coat%5C+appearance%2C%5C+inner%5C+tangential%5C+wall%5C+and%5C+thickenings%5C+of%5C+radial%5C+wall.%5C+Fruit%5C+and%5C+seed%5C+data%5C+reflect%5C+the%5C+close%5C+relationships%5C+within%5C+%E2%80%9CPterygiella%5C+complex%E2%80%9D.%5C+While%2C%5C+Xizangia%5C+was%5C+distinctly%5C+different%5C+from%5C+Pterygiella.%5C+Phtheirospermum%5C+tenuisectum%5C+was%5C+more%5C+similar%5C+to%5C+the%5C+member%5C+of%5C+section%5C+minutisepala%5C+within%5C+the%5C+genus%5C+Phtheiroseprmum.%5C+Phtheirospermum%5C+japonicum%5C+was%5C+heterogeneous%5C+within%5C+the%5C+genus%5C+Phtheirospermum.%5C+On%5C+the%5C+whole%2C%5C+fruit%5C+and%5C+seed%5C+data%5C+supported%5C+Xizangia%5C+and%5C+Pseudobartsia%5C+as%5C+a%5C+genus%5C+rank%5C+and%5C+Phtheirospermum%5C+japonicum%5C+was%5C+a%5C+heterogeneous%5C+member%5C+in%5C+Phtheirospermum"},{"jsname":"Innovation Program of the Chinese Academy of Sciences[KSCX2-YW-Z-0926]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AInnovation%5C+Program%5C+of%5C+the%5C+Chinese%5C+Academy%5C+of%5C+Sciences%5C%5BKSCX2%5C-YW%5C-Z%5C-0926%5C%5D"},{"jsname":"Joint Fund of National Natural Science Foundation of China-Yunnan Province[U1502261]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AJoint%5C+Fund%5C+of%5C+National%5C+Natural%5C+Science%5C+Foundation%5C+of%5C+China%5C-Yunnan%5C+Province%5C%5BU1502261%5C%5D"},{"jsname":"Keynote Projects of the National Natural Science Foundation of China[40830209]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3AKeynote%5C+Projects%5C+of%5C+the%5C+National%5C+Natural%5C+Science%5C+Foundation%5C+of%5C+China%5C%5B40830209%5C%5D"},{"jsname":"Light of West China Program of the Chinese Academic of Sciences","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Polymorphic&&fq=dc.project.title_filter%3ALight%5C+of%5C+West%5C+China%5C+Program%5C+of%5C+the%5C+Chinese%5C+Academic%5C+of%5C+Sciences"},{"jsname":"lastIndexed","jscount":"2024-06-17"}],"资助项目","dc.project.title_filter")'>
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