Evolutionary importance of the relationship between cytogeography and climate:New insights on creosote bushes from North and South America  

作　　者：Romina Vidal-Russell Mariana Tadey Romana Urfusova Tomás Urfus Cintia Paola Souto 

机构地区：[1]Laboratorio Ecotono-INIBIOMA(CONICET-UNComahue),Quintral,1250,Bariloche,Río Negro,Argentina [2]Department of Botany,Faculty of Science,Charles University,Benátská2,12800,Prague,Czech Republic

出　　处：《Plant Diversity》2022年第5期492-498,共7页植物多样性（英文版）

基　　金：supported by Argentine National Found for Science and Technology,under Grant PICT 2014-3478-BID and 20190149 BID;Council of Science and Technology-CONICET under Grant PIP-0712.R.V.R.,M.T.,and C.P.S.are members of CONICET. Grant Agency of the Czech Republic 17-12420S

摘　　要：Relationships between genome size and environmental variables suggest that DNA content might be adaptive and of evolutionary importance in plants.The genus Larrea provides an interesting system to test this hypothesis,since it shows both intra-and interspecific variation in genome size.Larrea has an amphitropical distribution in North and South American deserts,where it is most speciose.Larrea tridentata in North America shows a gradient of increasing autopolyploidy;while three of the four studied South American species are diploids,Larrea divaricata,Larrea nitida,Larrea ameghinoi,and the fourth is an allopolyploid,Larrea cuneifolia.We downloaded available focal species’georeferenced records from seven data reservoirs.We used these records to extract biologically relevant environmental variables from WorldClim at 30 arc seconds scale,to have a broad characterization of the variable climatic conditions of both regions,and a climatic envelope for each species.We estimated relative DNA content index and relative monoploid genome values,by flow cytometry,of four most abundant Larrea species throughout their respective ranges.Then we winnow the bioclimatic dataset down to uncorrelated variables and sampled locales,to analyse the degree of association between both intra-and interspecific relative DNA content and climatic variables that are functionally relevant in arid environments using Pearson correlations,general linear and mixed effects models.Within the genus Larrea,relative DNA content increases with rising temperature and decreases with rising precipitation.At the intraspecific level,all four species show relative DNA content variation across climatic conditions.Larrea is a genus that shows genome size variation correlated with climate.Our results are also consistent with the hypothesis that extreme environmental pressures may have facilitated repeated whole genome duplication events in North America,while in South America,reticulate evolution,as allopolyploidization,and speciation might have been climate-depe

关 键 词：DNA content DRYLANDS Genome size Jarilla Larrea ZYGOPHYLLACEAE 

分 类 号：Q948[生物学—植物学]