Cryptic diversity and significant cophylogenetic signal detected by DNA barcoding the rust fungi (Pucciniaceae) of Cyperaceae-Juncaceae  

作　　者：Étienne Léveillé-Bourret Quinn Eggertson Sarah Hambleton Julian R.Starr 

机构地区：[1]Département de sciences biologiques,Institut de recherche en biologie végétale(IRBV),Universitéde Montréal,4101 Sherbrooke E,Montréal,QC H1X 2B2,Canada [2]Biodiversity and Bioresources,Agriculture and Agri-Food Canada,960 Carling Avenue,Ottawa,ON K1A 0C6,Canada [3]Department of Biology,University of Ottawa,30 Marie Curie,Ottawa,ON K1N 6N5,Canada

出　　处：《Journal of Systematics and Evolution》2021年第4期833-851,共19页植物分类学报（英文版）

基　　金：supported by funding from the Genomics Research and Development Initiative(GRDI-QIS,Project ID 2679)of the Government of Canada(https://grdi.canada.ca/en);supported by National Science and Engineering Research Council of Canada(NSERC)Discovery Grants to JRS(RGPINs 342278-2013 and 2018-04115).

摘　　要：Plants play important roles as habitat and food for a tremendous diversity of specialist animals and fungi.The disappearance of any plant species can lead to extinction cascades of its associated biota.In consequence,documenting the diversity and specificity of plant-associated organisms is of high practical relevance in biodiversity conservation.Here,we present the first large-scale molecular investigation into the diversity,host specificity,and cophylogenetic congruence of an especially rich plant-fungal association,the rust fungi(Pucciniaceae)of Cyperaceae and Juncaceae.Using the largest rust fungi DNA barcoding dataset published to date(252 sequences,82 taxa),we reject the presence of a global ITS2-28S barcode gap,but find a local gap in Cyperaceae-Juncaceae rusts,and suggest the existence of many cryptic species in North America,with some broadly circumscribed species possibly corresponding to>10 cryptic species.We test previous hypotheses of correlations between the phylogenies of rust fungi and their Cyperaceae-Juncaceae hosts using a combination of global-fit and event-based cophylogenetic methods.A significant cophylogenetic signal is detected between rusts and their hosts,but the small number of cospeciations argues for preferential host jumps as the driving process behind these correlations.In addition,temporal congruence between the origin of major Carex clades and their rusts suggests that host diversification may have promoted parasite diversification.Finally,we discuss the relevance of rust infection patterns to the systematics of Cyperaceae,highlight some taxonomic problems uncovered by the analyses,and call attention to the promise of DNA barcoding for bridging knowledge gaps in poorly studied plant-associated microorganisms.

关 键 词：coevolution HOST-PARASITE molecular phylogenetics PHYTOPATHOLOGY Pucciniomycotina rushes SEDGES Pucciniales 

分 类 号：Q94[生物学—植物学]