@ARTICLE{TreeBASE2Ref27547, author = {Niloofar Vaghefi and Julie R Kikkert and Frank S Hay and gavriela Dena Carver and Lori Blair Koenick and Melvin D. Bolton and Linda Hanson and Gary Allen Secor and Sarah J Pethybridge}, title = {Cryptic diversity, pathogenicity, and evolutionary species boundaries in Cercospora populations associated with Cercospora leaf spot of Beta vulgaris}, year = {2017}, keywords = {}, doi = {}, url = {http://}, pmid = {}, journal = {IMA Fungus}, volume = {}, number = {}, pages = {}, abstract = {Cercospora is one of the largest genera of hyphomycetes accommodating several important phytopathogenic species associated with foliar diseases of vegetable and field crops. Cercospora leaf spot (CLS), caused by C. beticola, is a destructive disease of Beta vulgaris (sugar beet, table beet and swiss chard) worldwide. Previous genotyping-by-sequencing studies suggested the presence of multiple Cercospora species in association with CLS symptoms on B. vulgaris. This study investigated the taxonomy and evolutionary species boundaries in a global collection of Cercospora isolates (n = 102) from B. vulgaris, based on sequences of six loci; internal transcribed spacer of the nrDNA, calmodulin, actin, histone H3, translation elongation factor 1-alpha, and the gene encoding for cercosporin facilitator protein. Species boundaries were assessed using concatenated multi-locus phylogenies, Generalized Mixed Yule Coalescent, Poisson Tree Processes, and Bayes factor delimitation (BFD) framework. Cercospora beticola was confirmed as the primary cause of CLS on B. vulgaris. Cercospora apii, C. cf. flagellaris, Cercospora sp. G, and C. zebrina were also identified in association with CLS on B. vulgaris. Cercospora apii and C. cf. flagellaris were pathogenic to table beet but Cercospora sp. G and C. zebrina did not cause disease. While Genealogical concordance phylogenetic species recognition, GMYC and PTP methods failed to differentiate C. apii and C. beticola as separate species, multi-species coalescent analysis based on BFD supported separation of C. apii and C. beticola into distinct species, and provided evidence of evolutionary independent lineages within C. beticola. Extensive intra- and intergenic recombination, incongruency of gene genealogies and dominance of clonal reproduction in some species complicate evolutionary species recognition in the genus Cercospora. Host association based on the substrate from which Cercospora species have been isolated was found to provide little value for determining taxonomic position. The results indicated that the number of Cercospora species associated with CLS on B. vulgaris has been underestimated. The implications for these findings suggest morphological and phylogenetic analyses to disentangle cryptic speciation within C. beticola may be warranted. } }

• Go to search
• Citation
• Taxa
• Matrices
• Trees
• Analyses
• 

CiteULike

Delicious

Connotea