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A leaf spot disease was observed on cabbage (Brassica oleraceaL. var.capitata) affecting 80% of plants growing in greenhouses and fields in Serdang, Selangor, Malaysia. Symptomatic leaf samples were collected from infected plants and isolations made on agar medium. Single-spore isolates from resulting colonies were identified based on cultural and morphological characteristics asPithomyces chartarum. Morphological identification was confirmed by sequence analysis of the internal transcribed spacer (ITS) regions 1 and 2, including 5.8S rDNA (ITS1-5.8S-ITS2). Pathogenicity tests indicated thatP. chartarumcauses leaf spot on cabbage. This is the first report of leaf spot caused byP. chartarumon cabbage in Malaysia. [ABSTRACT FROM PUBLISHER]

Among dinoflagellates responsible for benthic harmful algal blooms, the genus Ostreopsis primarily described from tropical areas has been increasingly reported from subtropical and temperate areas worldwide. Several species of this toxigenic genus produce analogs of palytoxin, thus representing a major threat to human and environmental health. The taxonomy of several species needs to be clarified as it was based mostly on morphological descriptions leading in some cases to ambiguous interpretations and misidentifications. The present study aims at reporting a benthic bloom that occurred in April 2019 in Tahiti island, French Polynesia. A complete taxonomic investigation of the blooming Ostreopsis species was realized using light, epifluorescence and field emission electron microscopy and phylogenetic analyses inferred from LSU rDNA and ITS-5.8S rDNA regions. Toxicity of a natural sample and strains isolated from the bloom was assessed using both neuroblastoma cell-based assay and LC-MS/MS analyses. Morphological observations showed that cells were round to oval, large, 58.0-82.5 µm deep (dorso-ventral length) and 45.7-61.2 µm wide. The cingulum was conspicuously undulated, forming a 'V' in ventral view. Thecal plates possessed large pores in depressions, with a collar rim. Detailed observation also revealed the presence of small thecal pores invisible in LM. Phylogenetic analyses were congruent and all sequences clustered within the genotype Ostreopsis sp. 6, in a subclade closely related to sequences from the Gulf of Thailand and Malaysia. No toxicity was found on the field sample but all the strains isolated from the bloom were found to be cytotoxic and produced ostreocin D, a lower amount of ostreocins A and B and putatively other compounds. Phylogenetic data demonstrate the presence of this species in the Gulf of Thailand, at the type locality of O. siamensis, and morphological data are congruent with the original description and support this identification., (Copyright © 2020 Elsevier B.V. All rights reserved.)