Speciation, phylogeny and barcoding of Peronospora
Abstract
Peronospora is the most species-rich genus of the obligate parasitic downy mildews (Peronosporales, Oomycetes). It contains pathogens of numerous crops. Numerous hosts from 48 host families of angiosperms are parasitized, and species numbers of the Peronospora are given between 65 to ca. 400, resulting in substantial uncertainties concerning species circumscription, taxonomy and host range. Despite its economic and ecological importance no modern systematic monograph is available. Detailed investigations on phylogeny, evolutionary radiation, speciation and species delimitation are lacking. Up to now no reliable molecular identification tool (molecular barcoding) which conforms to high quality standards is yet available. Therefore, the aims of the project are: a. A multi gene analysis based on selected mitochondrial and nuclear markers to obtain detailed insights into phylogenetic relationships and evolutionary radiation within the genus Peronospora. b. Speciation and host parasite radiation shall be investigated within selected groups, based on several phylogenetically informative mitochondrial and nuclear markers. Selected Peronospora groups shall serve as model for microevolution and shall be thouroughly sampled. Cophylogeny between pathogens and hosts shall be investigated with combined sequence datasets. c. Species concepts and delimitation shall be investigated within the groups selected for microevolution by multigene data sets. The concept of the Genealogical Concordance of the Phylogenetic Species Recognition (GCPSR) shall be applied to nuclear and mitochondrial markers. d. Taxonomic revisions shall be done to resolve nomenclatural problems and uncertainties to stabilize nomenclature and to provide a sound basis for identification. This will be supplemented by morphological investigations of herbarium specimens. e. New species of Peronospora shall be described following thorough morphological and molecular investigations. f. The investigated variable markers shall be tested for molecular barcoding. The results shall serve as basis for recommendations for selecting an official barcoding region for downy mildews. The sequence data will be deposited in BOLD (Barcode of Life Data Systems). To enable these investigations, numerous fresh collections of the applicant will be supplemented by field collections in various geographic regions.
Peronospora downy mildews Phylogeny molecular barcoding speciation taxonomy
Publikationen
Project staff
Hermann Voglmayr
Priv.-Doz. Mag. Dr. Hermann Voglmayr
hermann.voglmayr@boku.ac.at
Project Leader
01.10.2013 - 30.11.2014