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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.project.title_filter&advanced=false&query1=LIMITS&&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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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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a field trip at a brule in Shangri-La, a mixed population of Ligularia Cass. was found, which including L. subspicata (Bur. et Franch.) Hand.-Mazz., L. nelumbifolia (Bur. et Franch.) Hand.-Mazz., L. tongolensis (Franch.) Hand.-Mazz., L. cymbulifera (W.W.Smith) Hand.-Mazz., L. lingiana S.W.Liu, and also some individuals morphologically intermediate between L. subspicata and L. nelumbifolia. Hence, these intermediate individuals were preliminarily assumed as natural hybrids of the two Ligularia. According to their morphology, they’re assumed to form hybrids A and B. Through careful comparison of specimens in herbarium and those we collected, the inflorescence of putative hybrid A is close to L. nelumbifolia, but the shape of laminae are intergradation of L. subspicata and L. nelumbifolia; overall morphology of putative hybrids B is similar to L. nelumbifolia, but inflorescence color is as same as L. subspicata. Compared to L. nelumbifolia (39%) and L. subspicata (36.8%), the germination rate of putative hybrid B (45.7%) slightly higher than the two; but that of hybrid A is extraordinarily low (0.3%). One possible interpretation of the low rate is hybridization. 60 individuals were collected, including putative parents, other 4 species of Ligularia nearby, putative hybrid A and B. They were all direct sequenced of four cpDNA fragments, and direct sequenced or cloning sequenced of nrDNA ITS4-5. The results support that L. nelumbifolia and L. subspicata are parents of putative hybrid A, and the majority female parent is L. subspicata, L. vellerea may also be involved in the hybridization in some degree; the nuclear sequences of putative hybrid B have no superposition, and its chloroplast DNA sequences are identical with L. nelumbifolia, so putative hybrid B could not be hybrid; and there are backcross individuals exist among the putative parent L. subspicata. NewHybrids analysis of ISSR markers indicated that, the individuals of putative hybrid A are almost L. nelumbifolia and L. subspicata F1 hybrid generation (10/11), only 1/11 possibly backcross or other forms; all individuals of hybrid B are L. nelumbifolia; except one individual of L. subspicata as backcrossed, the other parent individuals are 100% reliable. This study focused on molecular evidence, complemented by ecological, reproductive and other characteristics, we demonstrated that the morphologically intermediate individuals’ origin, and the probability of belonging to each parental or hybrid class. And concluded that L. nelumbifolia and L. subspicata are the parents of putative hybrid A, L. vellerea may also be involved in the hybridization in some degree, hybrids mainly are the first generation, a few individuals may be involved in backcross, and most probably backcross with L. subspicata according to the anthesis, while the assumption of hybrid B is not supported.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.project.title_filter&advanced=false&query1=LIMITS&&fq=dc.project.title_filter%3ADuring%5C+a%5C+field%5C+trip%5C+at%5C+a%5C+brule%5C+in%5C+Shangri%5C-La%2C%5C+a%5C+mixed%5C+population%5C+of%5C+Ligularia%5C+Cass.%5C+was%5C+found%2C%5C+which%5C+including%5C+L.%5C+subspicata%5C+%5C%28Bur.%5C+et%5C+Franch.%5C%29%5C+Hand.%5C-Mazz.%2C%5C+L.%5C+nelumbifolia%5C+%5C%28Bur.%5C+et%5C+Franch.%5C%29%5C+Hand.%5C-Mazz.%2C%5C+L.%5C+tongolensis%5C+%5C%28Franch.%5C%29%5C+Hand.%5C-Mazz.%2C%5C+L.%5C+cymbulifera%5C+%5C%28W.W.Smith%5C%29%5C+Hand.%5C-Mazz.%2C%5C+L.%5C+lingiana%5C+S.W.Liu%2C%5C+and%5C+also%5C+some%5C+individuals%5C+morphologically%5C+intermediate%5C+between%5C+L.%5C+subspicata%5C+and%5C+L.%5C+nelumbifolia.%5C+Hence%2C%5C+these%5C+intermediate%5C+individuals%5C+were%5C+preliminarily%5C+assumed%5C+as%5C+natural%5C+hybrids%5C+of%5C+the%5C+two%5C+Ligularia.%5C+According%5C+to%5C+their%5C+morphology%2C%5C+they%E2%80%99re%5C+assumed%5C+to%5C+form%5C+hybrids%5C+A%5C+and%5C+B.%5C+Through%5C+careful%5C+comparison%5C+of%5C+specimens%5C+in%5C+herbarium%5C+and%5C+those%5C+we%5C+collected%2C%5C+the%5C+inflorescence%5C+of%5C+putative%5C+hybrid%5C+A%5C+is%5C+close%5C+to%5C+L.%5C+nelumbifolia%2C%5C+but%5C+the%5C+shape%5C+of%5C+laminae%5C+are%5C+intergradation%C2%A0of%5C+L.%5C+subspicata%5C+and%5C+L.%5C+nelumbifolia%5C%3B%5C+overall%5C+morphology%5C+of%5C+putative%5C+hybrids%5C+B%5C+is%5C+similar%5C+to%5C+L.%5C+nelumbifolia%2C%5C+but%5C+inflorescence%5C+color%5C+is%5C+as%5C+same%5C+as%5C+L.%5C+subspicata.%5C+Compared%5C+to%5C+L.%5C+nelumbifolia%5C+%5C%2839%25%5C%29%5C+and%5C+L.%5C+subspicata%5C+%5C%2836.8%25%5C%29%2C%5C+the%5C+germination%5C+rate%5C+of%5C+putative%5C+hybrid%5C+B%5C+%5C%2845.7%25%5C%29%5C+slightly%5C+higher%5C+than%5C+the%5C+two%5C%3B%5C+but%5C+that%5C+of%5C+hybrid%5C+A%5C+is%5C+extraordinarily%5C+low%5C+%5C%280.3%25%5C%29.%5C+One%5C+possible%5C+interpretation%5C+of%5C+the%5C+low%5C+rate%5C+is%5C+hybridization.%5C+60%5C+individuals%5C+were%5C+collected%2C%5C+including%5C+putative%5C+parents%2C%5C+other%5C+4%5C+species%5C+of%5C+Ligularia%5C+nearby%2C%5C+putative%5C+hybrid%5C+A%5C+and%5C+B.%5C+They%5C+were%5C+all%5C+direct%5C+sequenced%5C+of%5C+four%5C+cpDNA%5C+fragments%2C%5C+and%5C+direct%5C+sequenced%5C+or%5C+cloning%5C+sequenced%5C+of%5C+nrDNA%5C+ITS4%5C-5.%5C+The%5C+results%5C+support%5C+that%5C+L.%5C+nelumbifolia%5C+and%5C+L.%5C+subspicata%5C+are%5C+parents%5C+of%5C+putative%5C+hybrid%5C+A%2C%5C+and%5C+the%5C+majority%5C+female%5C+parent%5C+is%5C+L.%5C+subspicata%2C%5C+L.%5C+vellerea%5C+may%5C+also%5C+be%5C+involved%5C+in%5C+the%5C+hybridization%5C+in%5C+some%5C+degree%5C%3B%5C+the%5C+nuclear%5C+sequences%5C+of%5C+putative%5C+hybrid%5C+B%5C+have%5C+no%5C+superposition%2C%5C+and%5C+its%5C+chloroplast%5C+DNA%5C+sequences%5C+are%5C+identical%5C+with%5C+L.%5C+nelumbifolia%2C%5C+so%5C+putative%5C+hybrid%5C+B%5C+could%5C+not%5C+be%5C+hybrid%5C%3B%5C+and%5C+there%5C+are%5C+backcross%5C+individuals%5C+exist%5C+among%5C+the%5C+putative%5C+parent%5C+L.%5C+subspicata.%5C+NewHybrids%5C+analysis%5C+of%5C+ISSR%5C+markers%5C+indicated%5C+that%2C%5C+the%5C+individuals%5C+of%5C+putative%5C+hybrid%5C+A%5C+are%5C+almost%5C+L.%5C+nelumbifolia%5C+and%5C+L.%5C+subspicata%5C+F1%5C+hybrid%5C+generation%5C+%5C%2810%5C%2F11%5C%29%2C%5C+only%5C+1%5C%2F11%5C+possibly%5C+backcross%5C+or%5C+other%5C+forms%5C%3B%5C+all%5C+individuals%5C+of%5C+hybrid%5C+B%5C+are%5C+L.%5C+nelumbifolia%5C%3B%5C+except%5C+one%5C+individual%5C+of%5C+L.%5C+subspicata%5C+as%5C+backcrossed%2C%5C+the%5C+other%5C+parent%5C+individuals%5C+are%5C+100%25%5C+reliable.%5C+This%5C+study%5C+focused%5C+on%5C+molecular%5C+evidence%2C%5C+complemented%5C+by%5C+ecological%2C%5C+reproductive%5C+and%5C+other%5C+characteristics%2C%5C+we%5C+demonstrated%5C+that%5C+the%5C+morphologically%5C+intermediate%5C+individuals%E2%80%99%5C+origin%2C%5C+and%5C+the%5C+probability%5C+of%5C+belonging%5C+to%5C+each%5C+parental%5C+or%5C+hybrid%5C+class.%5C+And%5C+concluded%5C+that%5C+L.%5C+nelumbifolia%5C+and%5C+L.%5C+subspicata%5C+are%5C+the%5C+parents%5C+of%5C+putative%5C+hybrid%5C+A%2C%5C+L.%5C+vellerea%5C+may%5C+also%5C+be%5C+involved%5C+in%5C+the%5C+hybridization%5C+in%5C+some%5C+degree%2C%5C+hybrids%5C+mainly%5C+are%5C+the%5C+first%5C+generation%2C%5C+a%5C+few%5C+individuals%5C+may%5C+be%5C+involved%5C+in%5C+backcross%2C%5C+and%5C+most%5C+probably%5C+backcross%5C+with%5C+L.%5C+subspicata%5C+according%5C+to%5C+the%5C+anthesis%2C%5C+while%5C+the%5C+assumption%5C+of%5C+hybrid%5C+B%5C+is%5C+not%5C+supported."},{"jsname":"Federal Ministry for Economic Cooperation and Development, Germany[13.1432.4-001.00]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.project.title_filter&advanced=false&query1=LIMITS&&fq=dc.project.title_filter%3AFederal%5C+Ministry%5C+for%5C+Economic%5C+Cooperation%5C+and%5C+Development%2C%5C+Germany%5C%5B13.1432.4%5C-001.00%5C%5D"},{"jsname":"Flower scent is a very important character in rose breeding. However, many of 25,000 rose cultivars have no scent or weak scent. The tea scent of modern roses mainly originated from Rosa odorata (Andrews) Sweet, which is one of the most important ancestors of modern cultivated roses and the very important rose breeding resource. Due to the land expanding, habitat fragmentation and so on, R. odorata has been listed as an endangered species in ‘Chinese Plant Red Data Book—Rare and Endangered Plants’ and as the third-category endangered species in ‘Chinese Rare and Endangered Protective Plants List’. Therefore, it is urgent to protect this species and studying the conservation genetics of R. odorata is essentially important to work out a strategy of conservation.R. odorata comprises three double-petaled varieties (R. odorata var. odorata, R. odorata var. erubescens, and R. odorata var. pseudindica) and one single-petaled variety (R. odorata var. gigantea). The taxonomy of the three double-petaled varieties of R. odorata has been disputed for a long time. They have been treated as intraspecific taxa of R. odorata var. gigantea or R. chinensis by different botanist. According to the morphological analyses, Hurst (1941) inferred that R. odorata var. odorata was the hybrid between R. odorata var. gigantea and R. chinensis. Therefore, in order to clarify the right protective units, two single-copy nuclear genes (GAPDH and ncpGS), together with two plastid loci (trnL-F and psbA-trnH) were applied to study the hybrid origin of the three double-petaled varieties and to identify their possible parents. Our data suggested the hybrid origin of the three double-petaled varieties. We inferred that R. odorata var. gigantea could be the maternal parent and R. chinensis cultivars be the paternal parent. It is strongly suggested that the conservation of R. odorata is the conservation of its wild type, R. odorata var. gigantea. We first applied seven microsatellite loci (SSR) coupled with a single-copy nuclear gene GAPDH to study the genetic diversity and genetic structure of R. odorata var. gigantea. The main results are shown as follows:1. Genetic diversity：R. odorata var. gigantea maintains high degree of genetic diversity within and among populations (SSR: HT = 0.738, HS = 0.569, AR = 5.583, PPB = 97.35%, I = 1.703; GAPDH: HT = 0.739, HS = 0.540). We inferred that, outcrossing, long-lived tree species, clonal reproduction and general intraspecies hybridization between individuals, have contributed to the high degree of genetic diversity in R. odorata var. gigantea.2. Genetic differentiation and genetic structure：There was some degree of genetic differentiation among populations (SSR: GST = 0.229, FST = 0.240; GAPDH: GST = 0.269). The geographic isolation limited the dispersal of pollen or seeds, which resulted in the limitation of gene flow (Nm = 0.792). Then, the limited gene flow should be accounted for the genetic differentiation. Both the results of SSR data and haplotype analysis of GAPDH indicated that, the studied populations were divided into two distinct groups by Honghe River. These two groups showed significant genetic differentiation and represented two separate evolutionary lineages, which should be recognized as two evolutionary significant units (ESUs) for conservation concerns.3. Conservation of R. odorata：R. odorata var. gigantea has been listed in the ‘National Key Protective Wild Species List (II)’. Therefore, the conservation of this species is urgent. We inferred that, the main endangered reasons should be the habitat fragmentation and the reduction of populations and individuals per population resulted from environmental damage and human activities. We proposed that the strategy of in-situ conservation combining with ex-situ conservation should be carried out.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.project.title_filter&advanced=false&query1=LIMITS&&fq=dc.project.title_filter%3AFlower%5C+scent%5C+is%5C+a%5C+very%5C+important%5C+character%5C+in%5C+rose%5C+breeding.%5C+However%2C%5C+many%5C+of%5C+25%2C000%5C+rose%5C+cultivars%5C+have%5C+no%5C+scent%5C+or%5C+weak%5C+scent.%5C+The%5C+tea%5C+scent%5C+of%5C+modern%5C+roses%5C+mainly%5C+originated%5C+from%5C+Rosa%5C+odorata%5C+%5C%28Andrews%5C%29%5C+Sweet%2C%5C+which%5C+is%5C+one%5C+of%5C+the%5C+most%5C+important%5C+ancestors%5C+of%5C+modern%5C+cultivated%5C+roses%5C+and%5C+the%5C+very%5C+important%5C+rose%5C+breeding%5C+resource.%5C+Due%5C+to%5C+the%5C+land%5C+expanding%2C%5C+habitat%5C+fragmentation%5C+and%5C+so%5C+on%2C%5C+R.%5C+odorata%5C+has%5C+been%5C+listed%5C+as%5C+an%5C+endangered%5C+species%5C+in%5C+%E2%80%98Chinese%5C+Plant%5C+Red%5C+Data%5C+Book%E2%80%94Rare%5C+and%5C+Endangered%5C+Plants%E2%80%99%5C+and%5C+as%5C+the%5C+third%5C-category%5C+endangered%5C+species%5C+in%5C+%E2%80%98Chinese%5C+Rare%5C+and%5C+Endangered%5C+Protective%5C+Plants%5C+List%E2%80%99.%5C+Therefore%2C%5C+it%5C+is%5C+urgent%5C+to%5C+protect%5C+this%5C+species%5C+and%5C+studying%5C+the%5C+conservation%5C+genetics%5C+of%5C+R.%5C+odorata%5C+is%5C+essentially%5C+important%5C+to%5C+work%5C+out%5C+a%5C+strategy%5C+of%5C+conservation.R.%5C+odorata%5C+comprises%5C+three%5C+double%5C-petaled%5C+varieties%5C+%5C%28R.%5C+odorata%5C+var.%5C+odorata%2C%5C+R.%5C+odorata%5C+var.%5C+erubescens%2C%5C+and%5C+R.%5C+odorata%5C+var.%5C+pseudindica%5C%29%5C+and%5C+one%5C+single%5C-petaled%5C+variety%5C+%5C%28R.%5C+odorata%5C+var.%5C+gigantea%5C%29.%5C+The%5C+taxonomy%5C+of%5C+the%5C+three%5C+double%5C-petaled%5C+varieties%5C+of%5C+R.%5C+odorata%5C+has%5C+been%5C+disputed%5C+for%5C+a%5C+long%5C+time.%5C+They%5C+have%5C+been%5C+treated%5C+as%5C+intraspecific%5C+taxa%5C+of%5C+R.%5C+odorata%5C+var.%5C+gigantea%5C+or%5C+R.%5C+chinensis%5C+by%5C+different%5C+botanist.%5C+According%5C+to%5C+the%5C+morphological%5C+analyses%2C%5C+Hurst%5C+%5C%281941%5C%29%5C+inferred%5C+that%5C+R.%5C+odorata%5C+var.%5C+odorata%5C+was%5C+the%5C+hybrid%5C+between%5C+R.%5C+odorata%5C+var.%5C+gigantea%5C+and%5C+R.%5C+chinensis.%5C+Therefore%2C%5C+in%5C+order%5C+to%5C+clarify%5C+the%5C+right%5C+protective%5C+units%2C%5C+two%5C+single%5C-copy%5C+nuclear%5C+genes%5C+%5C%28GAPDH%5C+and%5C+ncpGS%5C%29%2C%5C+together%5C+with%5C+two%5C+plastid%5C+loci%5C+%5C%28trnL%5C-F%5C+and%5C+psbA%5C-trnH%5C%29%5C+were%5C+applied%5C+to%5C+study%5C+the%5C+hybrid%5C+origin%5C+of%5C+the%5C+three%5C+double%5C-petaled%5C+varieties%5C+and%5C+to%5C+identify%5C+their%5C+possible%5C+parents.%5C+Our%5C+data%5C+suggested%5C+the%5C+hybrid%5C+origin%5C+of%5C+the%5C+three%5C+double%5C-petaled%5C+varieties.%5C+We%5C+inferred%5C+that%5C+R.%5C+odorata%5C+var.%5C+gigantea%5C+could%5C+be%5C+the%5C+maternal%5C+parent%5C+and%5C+R.%5C+chinensis%5C+cultivars%5C+be%5C+the%5C+paternal%5C+parent.%5C+It%5C+is%5C+strongly%5C+suggested%5C+that%5C+the%5C+conservation%5C+of%5C+R.%5C+odorata%5C+is%5C+the%5C+conservation%5C+of%5C+its%5C+wild%5C+type%2C%5C+R.%5C+odorata%5C+var.%5C+gigantea.%5C+We%5C+first%5C+applied%5C+seven%5C+microsatellite%5C+loci%5C+%5C%28SSR%5C%29%5C+coupled%5C+with%5C+a%5C+single%5C-copy%5C+nuclear%5C+gene%5C+GAPDH%5C+to%5C+study%5C+the%5C+genetic%5C+diversity%5C+and%5C+genetic%5C+structure%5C+of%5C+R.%5C+odorata%5C+var.%5C+gigantea.%5C+The%5C+main%5C+results%5C+are%5C+shown%5C+as%5C+follows%5C%3A1.%5C+Genetic%5C+diversity%EF%BC%9AR.%5C+odorata%5C+var.%5C+gigantea%5C+maintains%5C+high%5C+degree%5C+of%5C+genetic%5C+diversity%5C+within%5C+and%5C+among%5C+populations%5C+%5C%28SSR%5C%3A%5C+HT%5C+%3D%5C+0.738%2C%5C+HS%5C+%3D%5C+0.569%2C%5C+AR%5C+%3D%5C+5.583%2C%5C+PPB%5C+%3D%5C+97.35%25%2C%5C+I%5C+%3D%5C+1.703%5C%3B%5C+GAPDH%5C%3A%5C+HT%5C+%3D%5C+0.739%2C%5C+HS%5C+%3D%5C+0.540%5C%29.%5C+We%5C+inferred%5C+that%2C%5C+outcrossing%2C%5C+long%5C-lived%5C+tree%5C+species%2C%5C+clonal%5C+reproduction%5C+and%5C+general%5C+intraspecies%5C+hybridization%5C+between%5C+individuals%2C%5C+have%5C+contributed%5C+to%5C+the%5C+high%5C+degree%5C+of%5C+genetic%5C+diversity%5C+in%5C+R.%5C+odorata%5C+var.%5C+gigantea.2.%5C+Genetic%5C+differentiation%5C+and%5C+genetic%5C+structure%EF%BC%9AThere%5C+was%5C+some%5C+degree%5C+of%5C+genetic%5C+differentiation%5C+among%5C+populations%5C+%5C%28SSR%5C%3A%5C+GST%5C+%3D%5C+0.229%2C%5C+FST%5C+%3D%5C+0.240%5C%3B%5C+GAPDH%5C%3A%5C+GST%5C+%3D%5C+0.269%5C%29.%5C+The%5C+geographic%5C+isolation%5C+limited%5C+the%5C+dispersal%5C+of%5C+pollen%5C+or%5C+seeds%2C%5C+which%5C+resulted%5C+in%5C+the%5C+limitation%5C+of%5C+gene%5C+flow%5C+%5C%28Nm%5C+%3D%5C+0.792%5C%29.%5C+Then%2C%5C+the%5C+limited%5C+gene%5C+flow%5C+should%5C+be%5C+accounted%5C+for%5C+the%5C+genetic%5C+differentiation.%5C+Both%5C+the%5C+results%5C+of%5C+SSR%5C+data%5C+and%5C+haplotype%5C+analysis%5C+of%5C+GAPDH%5C+indicated%5C+that%2C%5C+the%5C+studied%5C+populations%5C+were%5C+divided%5C+into%5C+two%5C+distinct%5C+groups%5C+by%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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 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