The genus Phialocephala : a taxonomic study

Please read the abstract in the section 00front of this documentDissertation (MSc)--University of Pretoria, 2006.Microbiology and Plant PathologyUnrestricte

Fusarium diversity from the Golden Gate Highlands National Park

Members from the genus Fusarium can infect a broad range of plants and threaten agricultural and horticultural production. Studies on the diversity of Fusarium occurring in natural ecosystems have received less attention than the better known phytopathogenic members of the genus. This study identified Fusarium species from soils with low anthropogenic disturbance found in the Golden Gate Highlands National Park (GGHNP), a part of the Drakensberg system in South Africa. Selective techniques were implemented to obtain 257 individual isolates from the selected soil samples for which the translation elongation factor 1α (tef-1α) gene region was sequenced and compared against the Fusarium MLST and FUSARIUM-ID databases. Phylogenetic analyses, based on maximum likelihood and Bayesian inference, were used to determine species diversity in relation to reference isolates. Species level identifications were made within three of the seven species complexes and identified F. brachygibbosum, F. sporotrichioides, F. andiyazi, and F. gaditjirri based on the FUSARIUM-ID database, with F. transvaalense and F. lyarnte identified against the Fusarium MLST database. This indicated highly diverse populations of Fusarium from soils with low anthropogenic disturbance from the Afromontane grassland region found in mountain ranges

Fusarium species isolated from Pennisetum clandestinum collected during outbreaks of kikuyu poisoning in cattle in South Africa

Kikuyu poisoning occurs sporadically in South Africa. It is of major economic importance, as valuable dairy cows are often poisoned by it, and once affected, the mortality rate is high. Pennisetum clandestinum samples were collected during eight outbreaks of kikuyu poisoning in cattle in the Eastern Cape Province of South Africa from 2008 to 2010. The kikuyu grass samples were submitted specifically for the isolation and molecular identification of Fusarium species, as it was recently suggested that mycotoxins synthesised by Fusarium torulosum could be the cause of this intoxication. Ninety-four Fusarium isolates were retrieved from the grass samples, of which 72 were members of the Fusarium incarnatum/Fusarium equiseti species complex based on morphology and phylogenetic analyses of the translation elongation factor 1α sequence data. The South African isolates from kikuyu identified as members of the F. incarnatum/F. equiseti species complex grouped together in six separate clades. The other isolates were Fusarium culmorum (n = 3), Fusarium redolens (n = 4) and Fusarium oxysporum (n = 15). Although F. torulosum could not be isolated from P. clandestinum collected during kikuyu poisoning outbreaks in South Africa, the mycotoxicosis theory is still highly plausible.National Research Foundation (NRF)http://www.ojvr.orgtm201

Tarantulas (Araneae : Theraphosidae) in the pet trade in South Africa

CITATION: Shivambu, T.C. et al. 2020. Tarantulas (Araneae: Theraphosidae) in the pet trade in South Africa. African Zoology 55(4):323-336. doi:10.1080/15627020.2020.1823879The original publication is available at https://www.tandfonline.com/toc/tafz20/currentMany alien species have been introduced around the world as part of the pet trade, and some have escaped captivity and become invasive. In South Africa, many species of tarantula (Theraphosidae) are kept as pets. It is not known which species are traded, which are most popular, and whether their names are correctly applied. Online traders and physical pet stores were investigated between 2015 and 2016 to determine the extent or size of trade, species composition, most popular species, and their invasion history elsewhere. In total, 36 specimens, three individuals from 12 putative species, were also purchased for DNA barcoding targeting the COI gene region to quantify the accuracy of tarantula identification by traders. In total, 195 tarantula species were advertised for sale, and the most popular species were Brachypelma albopilosum Valerio, 1980 (n = 199), B. vagans Ausserer, 1875 (n = 132), and Grammostola rosea Walckenaer, 1837 (n = 120). The composition of shared species differed between the sources and most of the species were advertised online. Only one of the popular species, B. vagans, has been recorded as being invasive elsewhere. Only 36% of the barcoded specimens matched existing barcodes in online repositories that had the same species name. The three individuals from 12 putative species were not in the same terminal clade as those of conspecifics in the Barcode of Life Data System (BOLD) and the NCBI GenBank reference sequences. A large proportion of the known tarantula species are traded in South Africa and must be included in management and risk assessments to avoid potential invasions

The population structure of the Fusarium brachygibbosum species complex in the grassland biome of South Africa

Fusarium brachygibbosum Padwick is a phytopathogen with a widespread distribution, infecting various host plants. In South Africa, there is a limited number of studies on the genetic diversity of fusaria, particularly in undisturbed soils. In the current study, the genetic diversity of F. brachygibbosum was investigated using inter-simple sequence repeat (ISSR) and mating type genes. The F. brachygibbosum isolates were collected from four different geographic regions within the grassland biome of South Africa. A total of ten ISSR primers produced 64 distinct and reproducible amplicons, with 100% polymorphism. The ISSR markers revealed high levels of intraspecific variation, which is depicted by various genetic diversity indexes. In the analysis of mating type genes, the MAT1-1-2 gene was found among the four populations, but the MAT1-2-1 gene was only present in the population from the Groenkloof Nature Reserve. The data from this study will contribute substantially to knowledge of grassland fusaria of South Africa and their population structure in the grassland biome.NRF Thutuka, NRF FBIP and the University of Johannesburg URC/FRC grants. Open access funding provided by University of Johannesburg.https://www.springer.com/journal/13313hj2024BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologySDG-15:Life on lan

Taxonomy of species within the Gibberella fujikuroi complex

Fusarium was established to accommodate phialidic fungi with fusiform macroconidia borne on poly- or monophialides. They are characterised by significant variation in morphological characters. These morphological characteristics have been used as basis to demarcate species within the genus with a wide host range and cosmopolitan distribution. In the first chapter these morphological characters and other criteria used to demarcate species in the genus Fusarium are reviewed. Furthermore the predominant three species concepts applied to Fusarium are discussed. The second chapter of the thesis deals with polyphyletic nature pertaining to F. subglutinans sensu lato. This study was based on informative morphological characters as well as sequence data obtained from the translation elongation factor 1 , -tubulin and 28S regions of the rDNA gene region. The results indicate that F. subglutinans sensu lato represents at least thirteen independent species associated with a variety of hosts. This manuscript was submitted for peer-viewing. In the third chapter the taxonomic placement of a new Fusarium species from Poaceae, in South Africa is considered. Both morphological and molecular characters were used to determine the relationship of the new species to other species in the F. subglutinans sensu lato species complex and more specifically the two species, F. subglutinans sensu stricto and F. circinatum, with which it formed fertile sexual crosses. The Fusarium sp. isolated from Poaceae was described as Fusarium ophiodes sp. nov. This manuscript was submitted for peer-viewed. In the fourth chapter the causal agent of pine decline in Chilean nurseries are characterised as Fusarium ciricinatum. This was done by means of sexual crosses, phylogenetics and morphological comparisons. This led to the first report of the disease in Chile with different aspects published as two peer-reviewed articles. The last chapter deals with the generic placement of a new Fusarium species associated with Ananas comosus. The species was described as F. ananatum. It displays salmon colony colour with conidia produced by means of both poly- and monophialides. The erect aerial mycelium distinguishes it from the closely related species, F. guttiforme. Based on the sequence data obtained from the translation elongation factor 1 , -tubulin and histone 3 genes, this species represent a new species in F. subglutinans sensu lato. The study resulted in a peer-reviewed publication.Thesis (PhD)--University of Pretoria, 2011.Microbiology and Plant PathologyUnrestricte

Characterisation of Mycosphaerella species associated with pink spot on guava in South Africa

Pink spot symptoms on guava fruit in the Lowveld region were in the past attributed to Colletotrichum gloeosporioides, but recently Mycosphaerella species were suggested to be part of a disease complex, including pink spot symptoms. During routine surveys of guava diseases in the Lowveld area of the Mpumalanga Province in South Africa, Mycosphaerella species were consistently isolated from guava fruit. Colletotrichum gloeosporioides was also retrieved, especially from older, bigger lesions. The Mycosphaerella isolates were compared based on their growth characteristics in culture and on DNA sequences of the internal transcribed spacer region, large subunit of the ribosomal DNA as well as the β-tubulin and translation elongation factor 1α gene regions. The phylogenetic analyses indicate that the isolates from the present study represent at least three species not previously reported on guavas. This report is therefore the first report of Mycosphaerella species associated with Psidium guajava in South Africa

<i>Fusarium</i> species isolated from <i>Pennisetum clandestinum</i> collected during outbreaks of kikuyu poisoning in cattle in South Africa

Kikuyu poisoning occurs sporadically in South Africa. It is of major economic importance, as valuable dairy cows are often poisoned by it, and once affected, the mortality rate is high. Pennisetum clandestinum samples were collected during eight outbreaks of kikuyu poisoning in cattle in the Eastern Cape Province of South Africa from 2008 to 2010. The kikuyu grass samples were submitted specifically for the isolation and molecular identification of Fusarium species, as it was recently suggested that mycotoxins synthesised by Fusarium torulosum could be the cause of this intoxication. Ninety-four Fusarium isolates were retrieved from the grass samples, of which 72 were members of the Fusarium incarnatum/Fusarium equiseti species complex based on morphology and phylogenetic analyses of the translation elongation factor 1α sequence data. The South African isolates from kikuyu identified as members of the F. incarnatum/F. equiseti species complex grouped together in six separate clades. The other isolates were Fusarium culmorum (n = 3), Fusarium redolens (n = 4) and Fusarium oxysporum (n = 15). Although F. torulosum could not be isolated from P. clandestinum collected during kikuyu poisoning outbreaks in South Africa, the mycotoxicosis theory is still highly plausible