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The genus Elsinoe contains many aggressive pathogens of a wide range of plants, many of which are economically important. These fungal pathogens cause serious scab diseases affecting various plant parts, impacting plant vigour, yield and market value. While studies on Elsinoe species have predominantly focused on their taxonomy, there is a conspicuous gap in knowledge of these fungi from a plant pathology perspective. In this review, we draw together and critically evaluate the existing, but rather fragmented, research on the taxonomic status, phylogenetic relationships, host range, as well as the biology and epidemiology of Elsinoe species. Our aim is primarily to augment the existing understanding of the global significance of Elsinoe species, and furthermore, to shed light on the escalating prominence of scab diseases caused by species in a fungal genus that has been known for over 100 years but remains relatively poorly understood and somewhat enigmatic. [ABSTRACT FROM AUTHOR]

Two outbreaks of coffee wilt disease have devastated African coffee production. A PLOS Biology study suggests that horizontal gene transfer via large Starship transposons between 2 fungal species played a key role in the repeated emergence of the disease. Two outbreaks of coffee wilt disease have devastated African coffee production. A PLOS Biology study suggests that horizontal gene transfer via Starships between two fungal strains played a key role in the repeated emergence of the disease. [ABSTRACT FROM AUTHOR]

Canary Island date palm, Phoenix canariensis, is a popular ornamental species commonly planted in urban areas worldwide, including South Africa. In November 2023, symptoms typical of Fusarium wilt were detected on ornamental palms at the Waterfront in Cape Town, Western Cape Province, South Africa. Samples were collected from three wilting palms with one‐sided frond death and pink sporulation on the bark. Isolations to culture media yielded two fungal species, which were confirmed based on DNA sequence data as Fusarium oxysporum f.sp. canariensis (Foc) and Nalanthamala vermoesenii. Fusarium wilt, caused by Foc, is among the most serious diseases of these palms. There is no effective treatment for this vascular wilt disease and infected palms inevitably die. Pink rot, caused by N. vermoesenii, is commonly found as a secondary infection associated with Fusarium wilt in P. canariensis. This is the first detection of the Fusarium wilt and pink rot pathogens in South Africa. [ABSTRACT FROM AUTHOR]

Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) are small wood-boring insects that live in an obligate symbiosis with fungi, which serve as their primary food source. Beetles residing in the genus Euwallacea have evolved a unique association with a clade of Fusarium that falls within the aptly named Ambrosia Fusarium Clade (AFC). The discovery of the invasive polyphagous shot hole borer, E. fornicatus, in South Africa, has heightened awareness of ambrosia beetles and their symbionts in the country. In this study, we investigated the Fusarium symbionts of three species of Euwallacea in South Africa, with a specific focus on those associated with E. xanthopus. Isolations of Fusarium strains from both living and dissected beetles yielded nearly 100 isolates. Using multigene phylogenetic analyses, these isolates were identified as six different Fusarium species. Fusarium hypothenemi and F. euwallaceae have previously been reported from South Africa. Fusarium pseudensiforme and Fusarium AF-6 are new records for the country. The remaining two species are new to science and are described here as F. rufum sp. nov. and F. floriferum sp. nov. Targeted fungal isolation from specific beetle body parts revealed that the AFC species collected were typically associated with the dissected beetle heads and helped us identify the likely nutritional symbiont of E. xanthopus. This study highlights the understudied diversity of fungal associates of ambrosia beetles present in South Africa. [ABSTRACT FROM AUTHOR]

Sporotrichosis is a disease that arises from a fungal infection caused by members of the Ascomycete genus Sporothrix. The disease has a unique history in South Africa, due to an association with gold mines, where large numbers of mine workers were infected in the 1930s and 1940s. This was likely driven by hot humid conditions and timber supports used in these mine shafts. Furthermore, the disease is the most common subcutaneous fungal infection amongst the general population in South Africa, and the large number of immunocompromised individuals increases the public health risk in the country. Sporothrix is a genus in the Ophiostomatales, a fungal order primarily associated with environmental habitats. Unsurprisingly, sporotrichosis therefore has a documented history of sapronotic transmission from contaminated plant material. This review provides insights into the understanding of sporotrichosis and Sporothrix species, with a particular emphasis on the South African situation. We highlight knowledge gaps, particularly regarding the ecological factors influencing the occurrence and distribution of these species, which in turn affect the patterns of sporotrichosis. We also emphasise a need for ongoing proactive research and surveillance to prevent future outbreaks of sporotrichosis, an emerging disease with growing health implications worldwide. [ABSTRACT FROM AUTHOR]

Fungi in the Cryphonectriaceae are important canker pathogens of woody shrubs and trees in the Melastomataceae and Myrtaceae (Myrtales). During 2021 disease surveys in KwaZulu‐Natal (South Africa) plantations, a serious stem canker disease was discovered on species of Eucalyptus and Corymbia. The cankers had structures on their surfaces typical of fungi in the Cryphonectriaceae. The aims of the study were to identify the fungus associated with the disease and to test its pathogenicity. Morphological characteristics of both sexual and asexual structures and phylogenetic analyses based on partial sequences of the conserved nuclear large subunit (LSU) ribosomal DNA, the internal transcribed spacer (ITS) regions including the 5.8S gene of the ribosomal DNA operon, and two β‐tubulin (BT1/BT2) regions were used for identification purposes. Phylogenetic analyses of the sequence data and morphological characteristics supported the establishment of a new genus in the Cryphonectriaceae, for which the name Xanthoporthe myrticola gen. et sp. nov. is provided. Pathogenicity trials showed that isolates were pathogenic on tested Eucalyptus grandis and hybrids as well as Corymbia henryi. The results suggest that this is an emerging pathogen that could influence the sustainability of plantation forestry in South Africa. [ABSTRACT FROM AUTHOR]