Species diversity in Pseudocercospora

Abstract

Species of <i>Pseudocercospora</i> are commonly associated with leaf and fruit spots on diverse plant hosts in sub-tropical and tropical regions. <i>Pseudocercospora</i> spp. have mycosphaerella-like sexual morphs, but represent a distinct genus in <i>Mycosphaerellaceae</i> (<i>Mycosphaerellales</i>, <i>Dothideomycetes</i>). The present study adds a further 29 novel species of <i>Pseudocercospora</i> from 413 host species representing 297 host genera occurring in 60 countries and designates four epitypes and one lectotype for established names. This study recognises 329 species names, with an additional 69 phylogenetic lineages remaining unnamed due to difficulty in being able to unambiguously apply existing names to those lineages. To help elucidate the taxonomy of these species, a phylogenetic tree was generated from multi-locus DNA sequence data of the internal transcribed spacers and intervening 5.8S nuclear nrRNA gene (ITS), partial actin (<i>actA</i>), and partial translation elongation factor 1-alpha (<i>tef1</i>), as well as the partial DNA-directed RNA polymerase II second largest subunit (<i>rpb2</i>) gene sequences. Novel species described in this study include those from various countries as follows: <b>Australia</b>, <i>Ps. acaciicola</i> from leaf spots on <i>Acacia</i> sp., <i>Ps. anopter</i> from leaf spots on <i>Anopterus glandulosus</i>, <i>Ps. asplenii</i> from leaf spots on <i>Asplenium dimorphum</i>, <i>Ps. australiensis</i> from leaf spots on <i>Eucalyptus gunnii</i>, <i>Ps. badjensis</i> from leaf spots on <i>Eucalyptus badjensis</i>, <i>Ps. erythrophloeicola</i> from leaf spots on <i>Erythrophleum chlorostachys</i>, <i>Ps. grevilleae</i> from leaf spots on <i>Grevillea</i> sp., <i>Ps. lophostemonigena</i> from leaf spots on <i>Lophostemon confertus</i>, <i>Ps. lophostemonis</i> from leaf spots on <i>Lophostemon lactifluus</i>, <i>Ps. paramacadamiae</i> from leaf spots on <i>Macadamia integrifolia</i>, <i>Ps. persooniae</i> from leaf spots on <i>Persoonia</i> sp., <i>Ps. pultenaeae</i> from leaf spots on <i>Pultenaea daphnoides</i>, <i>Ps. tristaniopsidis</i> from leaf spots on <i>Tristaniopsis collina</i>, <i>Ps. victoriae</i> from leaf spots on <i>Eucalyptus globoidea</i>. <b>Brazil</b>, <i>Ps. musigena</i> from leaf spots on <i>Musa</i> sp<i>.</i> <b>China</b>, <i>Ps. lonicerae-japonicae</i> from leaf spots on <i>Lonicera japonica</i>, <i>Ps. rubigena</i> leaf spots on <i>Rubus</i> sp. <b>France (Réunion)</b>, <i>Ps. wingfieldii</i> from leaf spots on <i>Acacia heterophylla</i>. <b>Malaysia</b>, <i>Ps. musarum</i> from leaf spots on <i>Musa</i> sp. <b>Netherlands</b>, <i>Ps. rhododendri</i> from leaf spots on <i>Rhododendron</i> sp. <b>South Africa</b>, <i>Ps. balanitis</i> from leaf spots on <i>Balanites</i> sp<i>.</i>, <i>Ps. dovyalidicola</i> from leaf spots on <i>Dovyalis zeyheri</i>, <i>Ps. encephalarticola</i> from leaf spots on <i>Encephalartos</i> sp<i>.</i> <b>South Korea</b>, <i>Ps. grewiana</i> from leaf spots on <i>Grewia biloba</i>, <i>Ps. parakaki</i> from leaf spots on <i>Diospyros kaki</i>, <i>Ps. pseudocydoniae</i> from leaf spots on <i>Chaenomeles lagenaria</i>, <i>Ps. paracydoniae</i> from leaf spots on <i>Chaenomeles speciosa</i>. <b>Thailand</b>, <i>Ps. acerigena</i> from leaf spots on <i>Acer</i> sp<i>.</i>, <i>Ps. tectonigena</i> from leaf spots on <i>Tectona grandis</i>. Epitypes are designated for <i>Cercospora</i> bonjeaneae-rectae, <i>Cercospora halleriae</i>, <i>Ps. eucleae</i>, and an epitype as well as a lectotype for <i>Ps. macadamiae.</i> Results obtained in the present study contribute to a better understanding of the host specificity and distribution in <i>Pseudocercospora</i> spp., many of which represent important pathogens of food or fibre crops, or organisms of quarantine concern. <b>Citation:</b> Groenewald JZ, Chen YY, Zhang Y, Roux J, Shin H-D, Shivas RG, Summerell BA, Braun U, Alfenas AC, Ujat AH, Nakashima C, Crous PW (2024). Species diversity in <i>Pseudocercospora</i>. <i>Fungal Systematics and Evolution</i> <b>13</b>: 29-89. doi: 10.3114/fuse.2024.13.03.