Abstract
The oomycete Plasmopara obducens was first described on wild Impatiens noli-tangere in Germany in 1877. About 125 years later the first occurrence of P. obducens on cultivated I. walleriana in the United Kingdom was reported, and a worldwide epidemic followed. Although this pathogen is a major threat for ornamental busy lizzy, the identity of the pathogen remained unconfirmed and the high host specificity observed for the genus Plasmopara cast doubts regarding its determination as P. obducens. In this study, using multigene phylogenies and morphological investigation, it is revealed that P. obducens on I. noli-tangere is not the conspecific with the pathogen affecting I. walleriana and another ornamental balsam, I. balsamina. As a consequence, the new names P. destructor and P. velutina are introduced for the pathogens of I. walleriana and I. balsamina, respectively.
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Acknowledgements
This study was supported by LOEWE in the framework of the excellence cluster for Integrative Fungal Research (IPF). We are grateful for the careful revision of the manuscript by the anonymous reviewers. Author contributions were as follows. Conceived the study – MT, YJC; provided materials – MT, JK; VK, conducted experiments – MG, SP, analyzed data – MG, SP; wrote the manuscript – MG, MT, with contributions from the other authors. Conflicting interest statement – MT is a section editor of Mycological Progress.
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Görg, M., Ploch, S., Kruse, J. et al. Revision of Plasmopara (Oomycota, Peronosporales) parasitic to Impatiens . Mycol Progress 16, 791–799 (2017). https://doi.org/10.1007/s11557-017-1316-y
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DOI: https://doi.org/10.1007/s11557-017-1316-y