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资助项目
0.05). For some populations, germination capacity in 12-h photoperiod was significantly higher than that in completed darkness（W-FD: P < 0.01, W-JD: P < 0.05）.Genetic variation within and among six populations was assessed using AFLP markers. Genetic diversity was higher at species level (PPL = 69.19%, HE = 0.221) than at population level (PPL = 26.22%, HE = 0.095, Is =0.140), and populations in southeast Yunnan were strongly differentiated from those in southwest Yunnan (Nei’s GST = 0.575; FST = 0.655). UPGMA analysis demonstrated a clear genetic division between the two populations from DeHong (SW Yunnan; D-JD and D-HG) and the four from WenShan (SE Yunnan; W-FD, W-LH, W-ML, and W-MG). Within-population genetic variation was significantly correlated with population isolation (r(PPL) = -0.94, P = 0.006; r(HE) = -0.85, P = 0.032; r(Is) = -0.87, P = 0.025), but not with population size (r(PPL) = 0.63, P = 0.178; r(HE) = 0.54, P = 0.268; r(Is) = 0.56, P = 0.249).","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Acer&&fq=dc.project.title_filter%3ACraigia%5C+yunnanensis%5C+W.%5C+W.%5C+Smith%5C+%5C%26%5C+W.%5C+E.%5C+Evans%5C+%5C%28Tiliaceae%5C%29%5C+is%5C+an%5C+endangered%5C+deciduous%5C+tree%5C+species%5C+which%5C+has%5C+high%5C+scientific%5C+and%5C+economic%5C+value.%5C+C.%5C+yunnanensis%5C+is%5C+seriously%5C+threatened%5C+and%5C+has%5C+been%5C+pushed%5C+to%5C+the%5C+verge%5C+of%5C+extinction%5C+due%5C+to%5C+vegetation%5C+destruction%5C+in%5C+China%5C+and%5C+consequent%5C+contraction%5C+of%5C+its%5C+distribution.%5C+Hence%2C%5C+it%5C+was%5C+listed%5C+as%5C+a%5C+nationally%5C+rare%5C+and%5C+endangered%5C+plant%5C+in%5C+1999%5C+and%5C+has%5C+also%5C+been%5C+proposed%5C+as%5C+a%5C+second%5C-ranked%5C+plant%5C+for%5C+national%5C+protection%5C+in%5C+China%5C+and%5C+included%5C+in%5C+IUCN%5C+red%5C+list.%5C+As%5C+a%5C+scientifically%5C+important%5C+and%5C+valued%5C+tree%5C+species%5C+with%5C+endangered%5C+status%2C%5C+the%5C+wild%5C+populations%5C+of%5C+C.%5C+yunnanensis%5C+therefore%5C+represent%5C+is%5C+a%5C+genetic%5C+resource%5C+that%5C+must%5C+be%5C+conserved.%5C+To%5C+provide%5C+basic%5C+information%5C+for%5C+its%5C+conservation%2C%5C+the%5C+population%5C+dynamics%5C+and%5C+population%5C+size%5C+structures%2C%5C+pollination%5C+biology%5C+and%5C+breeding%5C+system%2C%5C+eleven%5C+fitness%5C-related%5C+characters%5C+and%5C+the%5C+genetic%5C+variability%5C+based%5C+on%5C+AFLP%5C+were%5C+comprehensively%5C+studied.%5C+The%5C+main%5C+results%5C+are%5C+summarized%5C+as%5C+follows%5C%3A%5C+A%5C+total%5C+of%5C+six%5C+wild%5C+populations%5C+of%5C+C.%5C+yunnanensis%5C+were%5C+found%5C+in%5C+two%5C+disjunct%5C+regions%5C+of%5C+Yunnan%2C%5C+i.e.%5C+WenShan%5C+%5C%28SE%5C+Yunnan%5C%29%5C+and%5C+DeHong%5C+%5C%28SW%5C+Yunnan%5C%29%2C%5C+from%5C+2005%5C+to%5C+2007.%5C+Additionally%2C%5C+in%5C+all%5C+but%5C+one%5C+of%5C+the%5C+populations%5C+we%5C+detected%2C%5C+mature%5C+trees%5C+were%5C+felled%5C+between%5C+2005%5C+and%5C+2007%2C%5C+so%5C+destruction%5C+of%5C+most%5C+of%5C+these%5C+populations%5C+is%5C+ongoing.%5C+Across%5C+the%5C+six%5C+populations%5C+of%5C+extant%5C+C.%5C+yunnanensis%5C+found%5C+during%5C+our%5C+study%2C%5C+the%5C+total%5C+number%5C+of%5C+mature%5C+%5C%28reproductive%5C%29%5C+individuals%5C+detected%5C+was%5C+584%5C+in%5C+2007%EF%BC%8Cplus%5C+larger%5C+numbers%5C+of%5C+seedling%5C+and%5C+resprouts%5C+from%5C+cut%5C+trunks.%5C+The%5C+result%5C+of%5C+surveying%5C+Population%5C+structure%5C+showed%5C+that%5C+there%5C+are%5C+two%5C+regeneration%5C+types%5C+which%5C+are%5C+seedlings%5C+and%5C+sprouts.%5C+Seedlings%5C+occurred%5C+abundantly%5C+in%5C+gaps%5C+or%5C+open%5C+areas%5C+and%5C+the%5C+size%5C+class%5C+frequency%5C+distributions%5C+were%5C+often%5C+discontinuous%2C%5C+and%5C+the%5C+same%5C+general%5C+pattern%5C+occurred%5C+in%5C+all%5C+the%5C+investigated%5C+populations%5C+for%5C+juveniles%5C+and%5C+adults.%5C+The%5C+numbers%5C+of%5C+seed%5C-origin%5C+individuals%5C+did%5C+however%5C+decline%5C+sharply%5C+with%5C+increasing%5C+size%2C%5C+indicating%5C+a%5C+high%5C+mortality%5C+rate%5C+going%5C+from%5C+seedling%5C+to%5C+sapling%5C+stage%5C+may%5C+be%5C+a%5C+problem%5C+for%5C+this%5C+species.%5C+Additionally%2C%5C+the%5C+cash%5C+crop%5C+cultivation%5C+and%5C+logging%5C+seriously%5C+threaten%5C+the%5C+survival%5C+of%5C+the%5C+species.%5C+We%5C+conducted%5C+field%5C+observations%5C+and%5C+artificial%5C+pollination%5C+experiments%5C+on%5C+the%5C+floral%5C+biology%2C%5C+pollination%5C+process%5C+and%5C+breeding%5C+system%5C+of%5C+Craigia%5C+yunnanensis%5C+in%5C+Fadou%2C%5C+Xichou%5C+county%5C+of%5C+Yunnan%5C+province.%5C+The%5C+lifespan%5C+of%5C+a%5C+single%5C+hermaphrodite%5C+flower%5C+is%5C+approximately%5C+3%5C-4%5C+days.%5C+A%5C+cyme%5C+has%5C+2%5C-9%5C+flowered.%5C+The%5C+flowering%5C+period%5C+of%5C+an%5C+inflorescence%5C+is%5C+usually%5C+5%5C-14%5C+days.%5C+The%5C+flowers%5C+of%5C+C.%5C+yunnanensis%5C+were%5C+protandrous.%5C+The%5C+stamens%5C+were%5C+within%5C+petal%5C-like%5C+staminodes%5C+in%5C+the%5C+opening%5C+flowers%5C+until%5C+the%5C+flower%5C+withered.%5C+Without%5C+touchment%2C%5C+the%5C+bractlike%5C+staminodes%5C+can%E2%80%99t%5C+open.%5C+Self%5C-pollination%5C+was%5C+partially%5C+avoided%5C+by%5C+temporal%5C+and%5C+spatial%5C+isolation%5C+of%5C+male%5C+and%5C+female%5C+organs%5C+within%5C+the%5C+same%5C+flower.%5C+However%2C%5C+autogamous%5C+and%5C+geitonogamous%5C+pollination%5C+is%5C+unavoidable%5C+because%5C+of%5C+the%5C+large%5C+number%5C+of%5C+flowers%5C+on%5C+a%5C+single%5C+tree%5C+and%5C+the%5C+action%5C+of%5C+pollinators.%5C+The%5C+values%5C+of%5C+both%5C+OCI%5C+%5C%28%E2%89%A54%5C%29%5C+and%5C+P%5C%2FO%5C+%5C%281381%5C%29%5C+and%5C+the%5C+results%5C+of%5C+bagging%5C+tests%5C+indicated%5C+there%5C+was%5C+no%5C+apomixes%5C+in%5C+C.%5C+yunnanensis%5C+and%5C+the%5C+breeding%5C+system%5C+of%5C+the%5C+species%5C+was%5C+outcrossing%5C+with%5C+partial%5C+self%5C-compatibility%5C+and%5C+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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 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China[2015MDTD16C]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Acer&&fq=dc.project.title_filter%3AMinzu%5C+University%5C+of%5C+China%5C%5B2015MDTD16C%5C%5D"},{"jsname":"Minzu University of China[YLDXXK201819]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Acer&&fq=dc.project.title_filter%3AMinzu%5C+University%5C+of%5C+China%5C%5BYLDXXK201819%5C%5D"},{"jsname":"Mt. Jiaozi from Yunnan is located in the eastern of the Central Yunnan Plateau, falling between the Pudu river and the Xiaojiang river, between the Jinshajiang river to the north and the Zhuanlong town of Luquan county to the south. It stands in the boundary of the Sino-Himalayan forest subkingdom and the Sino-Japan forest subkingdom, so it has a significant status, dew to the heterogeneous geographical environment and the sharp elevation drop in addition. Through field survey, specimens collection and identification and literatures consultion, we have obtained a brief list of Mt. Jiaozi, about 1517 species in 141 families and 531 genera, including varieties and subspices, among of which, there are 23 species in 7 families and 12 genera of gymnosperm. Based on statistic analysis, we get some conclusions as below. 1. As a type locality for many species, with various biodiversity and as much as endemism and some endangered plants, the flora of Mt. Jiaozi is viewed as a key area which should be paid special attention to. The flora constitution of this area has complex origins and multiple elements through the statistics. 2. The modern flora of Mt. jiaozi mainly includes the Chinese endemic elements and the Asian endemic elements, these two parts take up 81.65%. The characteristic of this flora is typically temperate. 3. Mt. Jiaozi is the north or the south distribution limitation to some important species as a floristic node. For example, species as Ephedra likiangensis, Solms-Laubachia pulcherrima, Soroseris hirsute, Paraquilegia microphylla which were used to be throught as limited in the northwestern of Yunnan had been found in this area. It indicates that, Mt. Jiaozi should become one of the foci of the flora regionalization in Yunnan, even in China. 4. In the view of the endemism of 6 families and 66 genera and 544 species in East Asian, this eara is a part of the East Asiatic Kingdom. The status of the flora of Mt. jiaozi in the East Asiatic Kingdom should be classified as Central Yunnan plateau subregion--Yunnan plateau region--Sino-Himalayan forest subkingdom.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Acer&&fq=dc.project.title_filter%3AMt.%5C+Jiaozi%5C+from%5C+Yunnan%5C+is%5C+located%5C+in%5C+the%5C+eastern%5C+of%5C+the%5C+Central%5C+Yunnan%5C+Plateau%2C%5C+falling%5C+between%5C+the%5C+Pudu%5C+river%5C+and%5C+the%5C+Xiaojiang%5C+river%2C%5C+between%5C+the%5C+Jinshajiang%5C+river%5C+to%5C+the%5C+north%5C+and%5C+the%5C+Zhuanlong%5C+town%5C+of%5C+Luquan%5C+county%5C+to%5C+the%5C+south.%5C+It%5C+stands%5C+in%5C+the%5C+boundary%5C+of%5C+the%5C+Sino%5C-Himalayan%5C+forest%5C+subkingdom%5C+and%5C+the%5C+Sino%5C-Japan%5C+forest%5C+subkingdom%2C%5C+so%5C+it%5C+has%5C+a%5C+significant%5C+status%2C%5C+dew%5C+to%5C+the%5C+heterogeneous%5C+geographical%5C+environment%5C+and%5C+the%5C+sharp%5C+elevation%5C+drop%5C+in%5C+addition.%5C+Through%5C+field%5C+survey%2C%5C+specimens%5C+collection%5C+and%5C+identification%5C+and%5C+literatures%5C+consultion%2C%5C+we%5C+have%5C+obtained%5C+a%5C+brief%5C+list%5C+of%5C+Mt.%5C+Jiaozi%2C%5C+about%5C+1517%5C+species%5C+in%5C+141%5C+families%5C+and%5C+531%5C+genera%2C%5C+including%5C+varieties%5C+and%5C+subspices%2C%5C+among%5C+of%5C+which%2C%5C+there%5C+are%5C+23%5C+species%5C+in%5C+7%5C+families%5C+and%5C+12%5C+genera%5C+of%5C+gymnosperm.%5C+Based%5C+on%5C+statistic%5C+analysis%2C%5C+we%5C+get%5C+some%5C+conclusions%5C+as%5C+below.%5C+1.%5C+As%5C+a%5C+type%5C+locality%5C+for%5C+many%5C+species%2C%5C+with%5C+various%5C+biodiversity%5C+and%5C+as%5C+much%5C+as%5C+endemism%5C+and%5C+some%5C+endangered%5C+plants%2C%5C+the%5C+flora%5C+of%5C+Mt.%5C+Jiaozi%5C+is%5C+viewed%5C+as%5C+a%5C+key%5C+area%5C+which%5C+should%5C+be%5C+paid%5C+special%5C+attention%5C+to.%5C+The%5C+flora%5C+constitution%5C+of%5C+this%5C+area%5C+has%5C+complex%5C+origins%5C+and%5C+multiple%5C+elements%5C+through%5C+the%5C+statistics.%5C+2.%5C+The%5C+modern%5C+flora%5C+of%5C+Mt.%5C+jiaozi%5C+mainly%5C+includes%5C+the%5C+Chinese%5C+endemic%5C+elements%5C+and%5C+the%5C+Asian%5C+endemic%5C+elements%2C%5C+these%5C+two%5C+parts%5C+take%5C+up%5C+81.65%25.%5C+The%5C+characteristic%5C+of%5C+this%5C+flora%5C+is%5C+typically%5C+temperate.%5C+3.%5C+Mt.%5C+Jiaozi%5C+is%5C+the%5C+north%5C+or%5C+the%5C+south%5C+distribution%5C+limitation%5C+to%5C+some%5C+important%5C+species%5C+as%5C+a%5C+floristic%5C+node.%5C+For%5C+example%2C%5C+species%5C+as%5C+Ephedra%5C+likiangensis%2C%5C+Solms%5C-Laubachia%5C+pulcherrima%2C%5C+Soroseris%5C+hirsute%2C%5C+Paraquilegia%5C+microphylla%5C+which%5C+were%5C+used%5C+to%5C+be%5C+throught%5C+as%5C+limited%5C+in%5C+the%5C+northwestern%5C+of%5C+Yunnan%5C+had%5C+been%5C+found%5C+in%5C+this%5C+area.%5C+It%5C+indicates%5C+that%2C%5C+Mt.%5C+Jiaozi%5C+should%5C+become%5C+one%5C+of%5C+the%5C+foci%5C+of%5C+the%5C+flora%5C+regionalization%5C+in%5C+Yunnan%2C%5C+even%5C+in%5C+China.%5C+4.%5C+In%5C+the%5C+view%5C+of%5C+the%5C+endemism%5C+of%5C+6%5C+families%5C+and%5C+66%5C+genera%5C+and%5C+544%5C+species%5C+in%5C+East%5C+Asian%2C%5C+this%5C+eara%5C+is%5C+a%5C+part%5C+of%5C+the%5C+East%5C+Asiatic%5C+Kingdom.%5C+The%5C+status%5C+of%5C+the%5C+flora%5C+of%5C+Mt.%5C+jiaozi%5C+in%5C+the%5C+East%5C+Asiatic%5C+Kingdom%5C+should%5C+be%5C+classified%5C+as%5C+Central%5C+Yunnan%5C+plateau%5C+subregion%5C-%5C-Yunnan%5C+plateau%5C+region%5C-%5C-Sino%5C-Himalayan%5C+forest%5C+subkingdom."},{"jsname":"National Key Basic Research Program of China[2014CB954100]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Acer&&fq=dc.project.title_filter%3ANational%5C+Key%5C+Basic%5C+Research%5C+Program%5C+of%5C+China%5C%5B2014CB954100%5C%5D"},{"jsname":"National Natural Science Foundation of China (NSFC)[31270496]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Acer&&fq=dc.project.title_filter%3ANational%5C+Natural%5C+Science%5C+Foundation%5C+of%5C+China%5C+%5C%28NSFC%5C%29%5C%5B31270496%5C%5D"},{"jsname":"lastIndexed","jscount":"2024-04-15"}],"资助项目","dc.project.title_filter")'>
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