Spatial isolation and genetic differentiation in naturally fragmented plant populations of the Swiss Alps  

作　　者：Patrick Kuss AndreaRPluess Hafdı´s HannaÆgisdottir Jurg Stocklin 

机构地区：[1]Institute of Botany,University of Basel,Schonbeinstrasse 6,CH-4056Basel,Switzerland [2]Institute of Plant Sciences,University of Bern,Altenbergrain21,CH-3013Bern,Switzerland [3]Institute for Terrestrial Ecosystems,Ecosystem Management,ETH Zurich,Universitatstrasse 16,8092 Zurich,Switzerland

出　　处：《Journal of Plant Ecology》2008年第3期149-159,共11页植物生态学报（英文版）

基　　金：supported by the Swiss National Science Foundation grants No.31-59271.99 and No.3100AO-100762 to J.S.and a grant of the Freiwillige Akademische Gesellschaft to H.H.Æ.

摘　　要：The effect of anthropogenic landscape fragmentation on the genetic diversity and adaptive potential of plant populations is a major issue in conservation biology.However,little is known about the partitioning of genetic diversity in alpine species,which occur in naturally fragmented habitats.Here,we investigate molecular patterns of three alpine plants(Epilobium fleischeri,Geum reptans and Campanula thyrsoides)across Switzerland and ask whether spatial isolation has led to high levels of population differentiation,increasing over distance,and a decrease of within-population variability.We further hypothesize that the contrasting potential for long-distance dispersal(LDD)of seed in these species will considerably influence and explain diversity partitioning.Methods For each study species,we sampled 20–23 individuals from each of 20–32 populations across entire Switzerland.We applied Random Amplified Polymorphic Dimorphism markers to assess genetic diversity within(Nei’s expected heterozygosity,He;percentage of polymorphic bands,Pp)and among(analysis of molecular variance,Ust)populations and correlated population size and altitude with within-population diversity.Spatial patterns of genetic relatedness were investigated using Mantel tests and standardized major axis regression as well as unweighted pair group method with arithmetic mean cluster analyses and Monmonier’s algorithm.To avoid known biases,we standardized the numbers of populations,individuals and markers using multiple random reductions.We modelled LDD with a high alpine wind data set using the terminal velocity and height of seed release as key parameters.Additionally,we assessed a number of important life-history traits and factors that potentially influence genetic diversity partitioning(e.g.breeding system,longevity and population size).Important findings For all three species,we found a significant isolation-by-distance relationship but only a moderately high differentiation among populations(Ust:22.7,14.8 and 16.8%,for E.fleischeri,G.repta

关 键 词：Campanula thyrsoides Epilobium fleischeri Geum reptans isolation by distance molecular diversity 

分 类 号：Q94[生物学—植物学]