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Abstract: Coniothyrium zuluense causes a serious canker disease of Eucalyptus in various parts of the world. Very little is known regarding the taxonomy of this asexual fungus, which was provided with a name based solely on morphological characteristics. In this study we consider the phylogenetic position of C. zuluense using DNA-based techniques. Distance analysis using 18S and ITS regions revealed extensive sequence divergence relative to the type species of Coniothyrium, C. palmarum and species of Paraconiothyrium. Coniothyrium zuluense was shown to be an anamorph species of Mycosphaerella, a genus that includes a wide range of Eucalyptus leaf and stem pathogens. Within Mycosphaerella it clustered with taxa having pigmented, verruculose, aseptate conidia that proliferate percurrently and sympodially from pigmented conidiogenous cells arranged in conidiomata that vary from being pycnidial to acervular. The genus Colletogloeopsis is emended to include species with pycnidial conidiomata, and the new combination Colletogloeopsis zuluense is proposed. This is also the first report of the pathogen from China where it is associated with stem cankers on Eucalyptus urophylla. [Copyright &y& Elsevier]

Citrus leaves and fruits exhibiting disease symptoms ranging from greasy spot, yellow spot, small or large brown spot, black dot, and brown dot were sampled from Fujian, Guangdong, Guizhou, Hunan, Jiangxi, Yunnan, Zhejiang provinces and the Guangxi Zhuang Autonomous Region in China. In total 82 isolates representing various cercosporoid genera were isolated from these disease symptoms, which were supplemented with eight Citrus cercosporoid isolates collected from other countries. Based on a morphological and phylogenetic study using sequence data from the nuclear ribosomal DNA's ITS1-5.8S-ITS2 regions (ITS), and partial actin (act), β-tubulin (tub2), 28S nuclear ribosomal RNA (28S rDNA) and translation elongation factor 1-α (tef1) genes, these strains were placed in the following genera: Cercospora, Pallidocercospora, Passalora, Pseudocercospora, Verrucisporota and Zasmidium. All isolates tended to be sterile, except the Zasmidium isolates associated with citrus greasy spot-like symptoms, which subsequently were compared with phylogenetically similar isolates occurring on Citrus and other hosts elsewhere. From these results four Zasmidium species were recognized on Citrus, namely Z. indonesianum on Citrus in Indonesia, Z. fructicola and Z. fructigenum on Citrus in China and Z. citri-griseum, which appears to have a wide host range including Acacia, Citrus, Eucalyptus and Musa, as well as a global distribution., (© 2015 by The Mycological Society of America.)