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Saxifraga paniculata Mill. is an amphi-atlantic species that is widely distributed in the Alps but also occurs with disjunct populations in central Europe. These isolated populations are considered to be glacial relicts. In the study presented here, we analysed the genetic variation within and between populations of Saxifraga paniculata in central Europe to test whether the molecular data give evidence for the supposed relict endemism. We used RAPD analysis and the analysis of molecular variance (AMOVA) technique to investigate 30 populations of Saxifraga paniculata from different locations in central Europe and adjacent geographical areas. In the RAPD analysis, 319 fragments could be amplified of which 91.2% were polymorphic. The percentage of polymorphic bands within populations correlated significantly with population size, indicating a higher level of inbreeding in small populations. AMOVA revealed 43.60% of the variation within populations, only 15.45% between populations within locations, and 40.95% between locations. Genetic distance between locations (ΦST) correlated significantly with the geographical distance between locations, giving evidence for geographical isolation. In an UPGMA cluster analysis, based on RAPD data, the populations were grouped together according to their location. The results exhibit a strong genetic differentiation which is obviously due to genetic drift in the isolated populations. Our study therefore gives evidence for glacial relict endemism of Saxifraga paniculata in central Europe.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 80, 11–21.  相似文献   
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Caladiums are popular ornamental plants that have not been wellstudied at the molecular level. Identification of species withinthe genus Caladium (Araceae) has been based primarily on morphology.However, the lack of comprehensive references makes identificationof Caladium cultivars extremely difficult. Amplified fragmentlength polymorphism (AFLP) analysis using 17 primer combinationswas carried out on two species of Caladium (C. bicolor and C.schomburgkii), including six cultivars of C. bicolor. Resultsshowed that AFLP can be used to distinguish these two speciesby their unique and different banding patterns. Unweighted PairGroup Method using Arithmetic Averages (UPGMA) permitted clusteranalysis of data from 17 selected primer combinations on sixcultivars of C. bicolor and one cultivar ofC. schomburgkii .It showed that closely related species can clearly be differentiatedand that genetic difference between cultivars can also be established.Unique AFLP molecular markers were detected for all the C. bicolorcultivars used. The use of AFLP has potential for preciselycharacterizing and identifying particular caladium cultivarsas well as for the registration of new cultivars. It will alsobe useful in future breeding programmes and systematics studies.Copyright 1999 Annals of Botany Company Araceae, Caladium species and cultivars, AFLP DNA fingerprinting, diversity, AFLP markers.  相似文献   
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