Journal Article

Habitat and Host Indicate Lineage Identity in Colletotrichum gloeosporioides s.l. from Wild and Agricultural Landscapes in North America

Oudemans, Peter V, Litt, Amy, Doyle, Vinson P, Rehner, Stephen A, Yun, Sung-Hwan

2013

Overview

Understanding the factors that drive the evolution of pathogenic fungi is central to revealing the mechanisms of virulence and host preference, as well as developing effective disease control measures. Prerequisite to these pursuits is the accurate delimitation of species boundaries. Colletotrichum gloeosporioides s.l. is a species complex of plant pathogens and endophytic fungi for which reliable species recognition has only recently become possible through a multi-locus phylogenetic approach. By adopting an intensive regional sampling strategy encompassing multiple hosts within and beyond agricultural zones associated with cranberry (Vaccinium macrocarpon Aiton), we have integrated North America strains of Colletotrichum gloeosporioides s.l. from these habitats into a broader phylogenetic framework. We delimit species on the basis of genealogical concordance phylogenetic species recognition (GCPSR) and quantitatively assess the monophyly of delimited species at each of four nuclear loci and in the combined data set with the genealogical sorting index (gsi). Our analysis resolved two principal lineages within the species complex. Strains isolated from cranberry and sympatric host plants are distributed across both of these lineages and belong to seven distinct species or terminal clades. Strains isolated from V. macrocarpon in commercial cranberry beds belong to four species, three of which are described here as new. Another species, C. rhexiae Ellis & Everh., is epitypified. Intensive regional sampling has revealed a combination of factors, including the host species from which a strain has been isolated, the host organ of origin, and the habitat of the host species, as useful indicators of species identity in the sampled regions. We have identified three broadly distributed temperate species, C. fructivorum , C. rhexiae , and C. nupharicola , that could be useful for understanding the microevolutionary forces that may lead to species divergence in this important complex of endophytes and plant pathogens.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Agricultural land / Agricultural production / Agriculture / Analysis / Bayes Theorem / Biology / Botany / Colletotrichum - classification / Colletotrichum - genetics / Colletotrichum - growth & development / Colletotrichum fructivorum / Colletotrichum gloeosporioides / Colletotrichum nupharicola / Colletotrichum rhexiae / control methods / Cranberries / Crop diseases / data collection / Disease control / Divergence / Ecology / Ecosystem / Endophytes / Evolution / Fruits / Fungi / Genes, Fungal / Genetics / Glomerella cingulata / Habitats / Host plants / Host preferences / indicator species / Landscape / Likelihood Functions / Loci / monophyly / Multilocus Sequence Typing / Mycological Typing Techniques / North America / Pathogens / Phylogenetics / Phylogeny / Plant diseases / Plant Diseases - microbiology / plant pathogens / Plant sciences / Plant Stems - microbiology / Recognition / Sampling / Specialization / Species / Studies / Sympatric populations / United States / Vaccinium macrocarpon / Vaccinium macrocarpon - microbiology / Virulence