Synopsis of Phyllosticta in China

Morphological and Phylogenetic Analyses Reveal Three New Species of Phyllosticta (Botryosphaeriales, Phyllostictaceae) in China

The genus Phyllosticta has been reported worldwide and contains many pathogenic and endophytic species isolated from a wide range of plant hosts. A multipoint phylogeny based on gene coding combinatorial data sets for the internal transcribed spacer (ITS), large subunit of ribosomal RNA (LSU rDNA), translation elongation factor 1α (TEF1α), actin (ACT), and glycerol-3-phosphate dehydrogenase (GPDH), combined with morphological characteristics, was performed. We describe three new species, P. fujianensis sp. nov., P. saprophytica sp. nov., and P. turpiniae sp. nov., and annotate and discusse their similarities and differences in morphological relationships and phylogenetic phases with closely related species.

Phyllosticta rizhaoensis sp. nov. causing leaf blight of Ophiopogon japonicus in China

Ophiopogon japonicus (Asparagaceae) is a perennial grass species which can be cultivated as an ornamental and medicinal plant. From April 2021 to September 2022, a serious leaf blight disease of O. japonicus was discovered in Rizhao City, Shandong Province, China. The initial disease symptoms were small yellow spots, finally developing as tip blight, often associated with many small, black, semi-immersed pycnidial conidiomata formed in lesions. To obtain isolates of the causal agent for this disease, samples were randomly collected from O. japonicus diseased leaves in Rizhao City. In total 97 Phyllosticta isolates were obtained from samples, and studied using morphological features and multi-locus phylogenetic analyses of a combined dataset using the internal transcribed spacers (ITS), the 28S large subunit of ribosomal RNA (LSU), and partial translation elongation factor 1-alpha (tef), actin (act) and glyceraldehyde-3-phosphate dehydrogenase (gapdh) loci. Phylogenetically, these Phyllosticta isolates formed a clade in the P. concentrica species complex, and clustered with P. pilospora and P. spinarum. Morphologically, isolates in this clade differed from P. pilospora and P. spinarum by the size of conidiogenous cells and conidia, and the absence of an apical conidial appendage. As a result, these isolates were described as a novel species Phyllosticta rizhaoensis. Pathogenicity was confirmed using Koch's postulates, which showed that P. rizhaoensis could induce leaf blight symptoms on O. japonicus in China. Citation: Wang C-B, Wang T-T, Ma C-Y, Xue H, Li Y, Piao C-G, Jiang N (2023). Phyllosticta rizhaoensis sp. nov. causing leaf blight of Ophiopogon japonicus in China. Fungal Systematics and Evolution 11: 43-50. doi: 10.3114/fuse.2023.11.03.

Morphological and phylogenetic analyses reveal two new species and a new record of Phyllosticta (Botryosphaeriales, Phyllostictaceae) from Hainan, China

The fungal genus Phyllosticta has been reported from all around the world and accommodates numerous pathogenic and endophytic species isolated from a wide range of plant hosts. Based on multilocus phylogenies from a combined dataset of genes encoding internal transcribed spacer (ITS), large subunit of ribosomal RNA (LSU rDNA), translation elongation factor 1 alpha (TEF1α), actin (ACT) and glycerol-3-phosphate dehydrogenase (GPDH), in conjunction with morphological characteristics, we describe two new species P.oblongifoliae sp. nov. and P.pterospermi sp. nov., as well as a new Chinese record P.capitalensis. Their similarity and dissimilarity to morphologically-allied and phylogenetically-related species are also annotated and discussed.

First Characterisation of the Phoma Species Complex on Maize Leaves in Central Europe

In the last decade, the cultivated area of maize has increased in Central Europe due to its high yield potential and diverse uses for feed and bio-energy. This has led to more intense maize cultivation, with narrowed crop rotations resulting in the increase in maize leaf diseases. During 2012 and 2013, an inventory of maize leaf spot diseases was carried out in various regions in Central Europe. In addition to the major leaf pathogens, isolates of Phoma-like species were obtained from oval to elliptical spots on leaves or found in lesions produced by other leaf pathogens. A total of 16 representative Phoma-like strains were characterised for their pathogenicity on maize leaves, for their morphological characteristics and with a phylogenetic analysis based on multilocus sequence analysis using part of the actin (ACT), calmodulin (CAL), β-tubulin (TUB), internal transcribed spacer (ITS) region of ribosomal DNA and large subunit ribosomal RNA (LSU) genes. The strains were grouped into four clades, and morphological studies supported this classification for most of them. Strains were compared with six reference Phoma-like species strains from the Westerndijk Fungal Biodiversity Institute collection reported to colonise maize. The pathogenic group of strains from our collection (after completion of Koch's postulates) did not cluster with any of these species, indicating a different and novel Phoma-like species infecting maize leaves. To our knowledge, this is the first study dissecting the Phoma species complex on maize leaves in Central Europe.

Occurrence of Phoma Sacc. in the phyllosphere of Neogene Siwalik forest of Arunachal sub-Himalaya and its palaeoecological implications

The present study reports in situ occurrence of two new epiphyllous fungal species of Phomites (comparable to modern genus Phoma Sacc.) on angiospermic leaf remains recovered from the Siwalik sediments (middle Miocene to early Pleistocene) of Arunachal Pradesh, eastern Himalaya. We describe two new species i.e. Phomites siwalicus Vishnu, Khan et Bera S, sp. nov. and Phomites neogenicus Vishnu, Khan et Bera S, sp. nov. on the basis of structural details of pycnidia. The pycnidium is a globose or slightly lens-shaped, ostiolate with a collar layer consisting of thick walled cells, sunken in leaf cuticle, with one-celled conidiospores and short-ampulliform conidiogenous cells. Host leaves resemble to those of extant Dipterocarpus C. F. Gaertn., Shorea Roxb. ex C. F. Gaertn. (Dipterocarpaceae), Dysoxylum Blume (Meliaceae), and Poaceae Barnhart. In situ occurrence of two Phomites morphotypes on the said leaf remains suggests a possible host-parasite interaction in the moist evergreen forest of Arunachal sub-Himalaya during Mio-Pleistocene period. The occurrence of Phomites in appreciable numbers indicates a humid climate favored by high rate of precipitation during Siwalik sedimentation, which is also consistent with our previously published climatic data obtained from the study of the macroscopic plant remains.