One stop shop: backbones trees for important phytopathogenic genera: I (2014)

Many fungi are pathogenic on plants and cause significant damage in agriculture and forestry. They are also part of the natural ecosystem and may play a role in regulating plant numbers/density. Morphological identification and analysis of plant pathogenic fungi, while important, is often hampered by the scarcity of discriminatory taxonomic characters and the endophytic or inconspicuous nature of these fungi. Molecular (DNA sequence) data for plant pathogenic fungi have emerged as key information for diagnostic and classification studies, although hampered in part by non-standard laboratory practices and analytical methods. To facilitate current and future research, this study provides phylogenetic synopses for 25 groups of plant pathogenic fungi in the Ascomycota, Basidiomycota, Mucormycotina (Fungi), and Oomycota, using recent molecular data, up-to-date names, and the latest taxonomic insights. Lineage-specific laboratory protocols together with advice on their application, as well as general observations, are also provided. We hope to maintain updated backbone trees of these fungal lineages over time and to publish them jointly as new data emerge. Researchers of plant pathogenic fungi not covered by the present study are invited to join this future effort. Bipolaris, Botryosphaeriaceae, Botryosphaeria, Botrytis, Choanephora, Colletotrichum, Curvularia, Diaporthe, Diplodia, Dothiorella, Fusarium, Gilbertella, Lasiodiplodia, Mucor, Neofusicoccum, Pestalotiopsis, Phyllosticta, Phytophthora, Puccinia, Pyrenophora, Pythium, Rhizopus, Stagonosporopsis, Ustilago and Verticillium are dealt with in this paper

Phytopythium: molecular phylogeny and systematics

The genus Phytopythium (Peronosporales) has been described, but a complete circumscription has not yet been presented. In the present paper we provide molecular-based evidence that members of Pythium clade K as described by Lévesque & de Cock (2004) belong to Phytopythium. Maximum likelihood and Bayesian phylogenetic analysis of the nuclear ribosomal DNA (LSU and SSU) and mitochondrial DNA cytochrome oxidase subunit 1 (COI) as well as statistical analyses of pairwise distances strongly support the status of Phytopythium as a separate phylogenetic entity. Phytopythium is morphologically intermediate between the genera Phytophthora and Pythium. It is unique in having papillate, internally proliferating sporangia and cylindrical or lobate antheridia. The formal transfer of clade K species to Phytopythium and a comparison with morphologically similar species of the genera Pythium and Phytophthora is presented. A new species is described, Phytopythium mirpurense

Characterization of a novel freshwater gigartinalean red alga from Belize, with description of Sterrocladia belizeana sp. nov

Freshwater representatives of the red algal order Gigartinales are extremely rare, with the monotypic genus Sterrocladia being the only truly freshwater example. This alga was described in 1850 from material originating from French Guiana, and although its affinities at the ordinal and familial levels have been debated based on morphological and anatomical characteristics, its placement has not been confirmed with the assistance of molecular analyses. Here we report several collections of a freshwater red alga from Belize that share many of the characteristics of the single described species, Sterrocladia amnica, but also display some important differences. Based on microscopic analysis, our collections were distinguished from S. amnica based on thickness of the cortical layer, cell size, possession of a loose versus entire medulla and absence of reproductive nemathecia. Transmission electron microscopy confirmed a pit plug anatomy consistent with placement of the new collections in the order Gigartinales, and a new method for resin infiltration into thick cortical tissue was described. Although recent material of S. amnica was unavailable, molecular phylogenetic analyses of the rbcL and SSU rRNA gene for our new samples indicated that it was indeed a member of the Gigartinales, and that it was positioned basal to the Gigartinaceae and Phyllophoraceae clades, likely representing a novel family. The COI-5P barcode sequence showed no close matches, but the vast majority of the closest hits were to representatives of the Phyllophoraceae. Here we describe a second species within the genus Sterrocladia to accommodate our Belizean collections, Sterrocladia belizeana sp. nov., and discuss the phylogenetic affinities of this unique genus of freshwater gigartinalean red algae. We also propose a lectotype of Sterrocladia amnica based on examination of syntype materials.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq