Two new species of Diaporthe (Diaporthaceae, Diaporthales) associated with tree cankers in the Netherlands

Abstract

<i>Diaporthe</i> (<i>Diaporthaceae</i>, <i>Diaporthales</i>) is a common fungal genus inhabiting plant tissues as endophytes, pathogens and saprobes. Some species are reported from tree branches associated with canker diseases. In the present study, <i>Diaporthe</i> samples were collected from <i>Alnusglutinosa</i>, <i>Fraxinusexcelsior</i> and <i>Quercusrobur</i> in Utrecht, the Netherlands. They were identified to species based on a polyphasic approach including morphology, pure culture characters, and phylogenetic analyses of a combined matrix of partial ITS, <i>cal</i>, <i>his3</i>, <i>tef1</i> and <i>tub2</i> gene regions. As a result, four species (viz.  <b><i>Diaporthepseudoalnea</i> sp. nov.</b> from <i>Alnusglutinosa</i>, <b><i>Diaporthesilvicola</i> sp. nov.</b> from <i>Fraxinusexcelsior</i>, <i>D.foeniculacea</i> and <i>D.rudis</i> from <i>Quercusrobur</i>) were revealed from tree branches in the Netherlands. <i>Diaporthepseudoalnea</i> differs from <i>D.eres</i> (syn. <i>D.alnea</i>) by its longer conidiophores. <i>Diaporthesilvicola</i> is distinguished from <i>D.fraxinicola</i> and <i>D.fraxini-angustifoliae</i> by larger alpha conidia.