Distinct phylogeographic structure recognized within Desmazierella acicola

Abstract

Desmazierella acicola (anamorph Verticicladium trifidum, Chorioactidaceae) represents a frequent colonizer of pine needles in litter. Considering the global diversity and distribution of pine species, we expected different phylogenetic lineages to exist in different geographical and climatic areas inhabited by these hosts. We compared DNA sequence data with phenotypic characteristics (morphology of the anamorph and growth at three different temperatures) of 43 strains isolated mostly from pine and also spruce needle litter sampled in various geographical areas. Analyses of ITS rDNA recovered eight geographically structured lineages. Fragments of genes for the translation elongation factor 1-α, and the second largest subunit of RNA polymerase II reproduced similar lineages, although not all of them were monophyletic. The similarity in ITS sequences among the clade with samples from Continental-Atlantic Europe and four other clades was lower than 95%. Several lineages exhibit also a tendency toward host specificity to a particular pine species. Growth tests at different temperatures indicated a different tolerance to specific climatic conditions in different geographic areas. However, the surveyed phenotypic characteristics also showed high variation within lineages, most evident in the morphology of the anamorph. Until a morphological study of the teleomorph is carried out, all of these lineages should be treated as distinct populations within a single species.

• anamorph morphology
• multigene analysis
• Pezizales
• population structure

Acknowledgments

We thank all colleagues and friends, who sampled pine litter needles on their journeys (in alphabetic order): Helena Bestová, Albert Damaška, Petr Dolejš, Miloš Duchoslav, Jana Duchoslavová, Tomáš Figura, Gábina Fuxová, Petr Janšta, Filip Kolář, Alexandra Koukolová, Dagmar Kozáková, Ariana Kubartová, Meike Piepenbring, Jiří Malíček, Martin Mullett, Alena Nováková, Zdeněk Palice, Dagmar Říhová, Petra Seifertová, Lucie Vančurová and Eliška Záveská. Special thanks to Donald Pfister for serving as a presubmission reviewer.

TM and OK were supported by the Institutional Resources of the Ministry of Education, Youth and Sports of the Czech Republic for the support of science and research.