Phylogenetics of the rust fungi (Pucciniales) of South Africa, with notes on their life histories and possible origins.

South Africa has an indigenous rust (Pucciniales) funga of approximately 460 species. This funga was sampled with species from as many genera as possible. The nuclear ribosomal large subunit (28S) region was amplified from samples representing 110 indigenous species, as well as the small subunit (18S) region and the cytochrome c oxidase subunit 3 (CO3) in some cases, and these were used in phylogenetic analyses. One new species is described, 12 new combinations made, six names reinstated, and two life history connections made. The life histories of this funga were summarized; it is dominated by species with contracted life histories. The majority of species are autoecious, with a small proportion being heteroecious. Of the autoecious species, many will likely be homothallic with no spermagonia. A shortened life history with homothallism allows for a single basidiospore infection to initiate a local population buildup under the prevailing unpredictable climatic conditions. Suggestions are made as to the possible origin of this funga based on the development of the modern South African flora. It is postulated that the rusts of South Africa are of relatively recent origin, consisting of three groups. Firstly, there is an African tropical element with members of the Mikronegerineae (Hemileia), the Sphaerophragmiaceae (Puccorchidium, Sphaerophragmium), and certain Uredinineae (Stomatisora). Their immediate ancestors likely occurred in the tropical forests of Africa during the Paleogene. Secondly, there is a pantropical element including the Raveneliaceae (e.g., Diorchidium, Maravalia, Ravenelia sensu lato, Uropyxis). This likely diversified during the Neogene, when the mimosoids became the dominant trees of the developing savannas. Thirdly, the Pucciniaceae invaded Africa as this continent pushed northward closing the Tethys Sea. They diversified with the development of the savannas as these become the dominant habitat in most of Africa, and are by far the largest component of the South African rust funga.

The life cycle of Puccinia digitariae on Digitaria eriantha and Solanum species in South Africa.

Rust fungi are important plant pathogens and have been extensively studied on crops and other host plants worldwide. This study describes the heterecious life cycle of a rust fungus on Digitaria eriantha (finger grass) and the Solanum species S. lichtensteinii (large yellow bitter apple), S. campylacanthum (bitter apple), and S. melongena (eggplant) in South Africa. Following field observations, inoculation studies involving telial isolates collected from Digitaria plants produced spermogonia and aecia on S. lichtensteinii, S. campylacanthum, and S. melongena. Likewise, inoculation of finger grass with aeciospores collected from the aforementioned Solanum species produced uredinia on D. eriantha. Pennisetum glaucum (pearl millet varieties Milkstar and Okashana, as well as 17 experimental lines) and S. elaeagnifolium (silverleaf nightshade or bitter apple) were resistant to the rust isolates. Morphological descriptions and molecular phylogenetic data confirmed the identity of the rust on Digitaria as P. digitariae, herein reinstated as a species and closely related to P. penicillariae the pearl millet rust, also reinstated. Puccinia digitariae has a macrocyclic, heterecious life cycle in which teliospores overwinter on dormant D. eriantha plants. Aecia sporulate on species of Solanum during spring and early summer to provide inocula that infect new growth of Digitaria.

Redescription of Mitodiplosis graminis (Diptera: Cecidomyiidae), a gall midge inhibiting the flowering of pyp grass Ehrharta villosa (Poaceae) in South Africa.

Mitodiplosis graminis Kieffer, the only species of the genus Mitodiplosis (Diptera: Cecidomyiidae), was described in 1914 as the causative agent of an unspecified gall on pyp grass Ehrharta villosa (Poaceae) in South Africa. The type specimens are presumed lost. We reared all developmental stages of the gall midge, redescribe here the male and female, and describe for the first time the gall, egg, larva and the pupa. Diagnosis of the genus Mitodiplosis is extended. The gall is a large thickening of the stem that becomes malformed and does not produce flowers. Pyp grass is an environmental weed in Australia and New Zealand and M. graminis can potentially be used as a biological control agent. With a wing length of over 6 mm in some specimens, M. graminis is one of the largest species of Cecidomyiidae.

The Genera of Fungi - fixing the application of the type species of generic names - G 2: Allantophomopsis, Latorua, Macrodiplodiopsis, Macrohilum, Milospium, Protostegia, Pyricularia, Robillarda, Rotula, Septoriella, Torula, and Wojnowicia.

The present paper represents the second contribution in the Genera of Fungi series, linking type species of fungal genera to their morphology and DNA sequence data, and where possible, ecology. This paper focuses on 12 genera of microfungi, 11 of which the type species are neo- or epitypified here: Allantophomopsis (A. cytisporea, Phacidiaceae, Phacidiales, Leotiomycetes), Latorua gen. nov. (Latorua caligans, Latoruaceae, Pleosporales, Dothideomycetes), Macrodiplodiopsis (M. desmazieri, Macrodiplodiopsidaceae, Pleosporales, Dothideomycetes), Macrohilum (M. eucalypti, Macrohilaceae, Diaporthales, Sordariomycetes), Milospium (M. graphideorum, incertae sedis, Pezizomycotina), Protostegia (P. eucleae, Mycosphaerellaceae, Capnodiales, Dothideomycetes), Pyricularia (P. grisea, Pyriculariaceae, Magnaporthales, Sordariomycetes), Robillarda (R. sessilis, Robillardaceae, Xylariales, Sordariomycetes), Rutola (R. graminis, incertae sedis, Pleosporales, Dothideomycetes), Septoriella (S. phragmitis, Phaeosphaeriaceae, Pleosporales, Dothideomycetes), Torula (T. herbarum, Torulaceae, Pleosporales, Dothideomycetes) and Wojnowicia (syn. of Septoriella, S. hirta, Phaeosphaeriaceae, Pleosporales, Dothideomycetes). Novel species include Latorua grootfonteinensis, Robillarda africana, R. roystoneae, R. terrae, Torula ficus, T. hollandica, and T. masonii spp. nov., and three new families: Macrodiplodiopsisceae, Macrohilaceae, and Robillardaceae. Authors interested in contributing accounts of individual genera to larger multi-authored papers to be published in IMA Fungus, should contact the associate editors listed for the major groups of fungi on the List of Protected Generic Names for Fungi (www.generaoffungi.org).

Morphological and molecular characterization of Endophyllum species on perennial asteraceous plants in South Africa.

Endophyllum osteospermi is an autoecious, endocyclic rust fungus, which has only been recorded on Chrysanthemoides monilifera ssp. monilifera (Asteraceae, Calendulae), a perennial woody shrub. Both organisms are indigenous to South Africa. Because E. osteospermi is being considered for release in Australia as a biocontrol agent against C. monilifera ssp. monilifera, it was necessary to determine its host range and natural distribution in South Africa. To address this, natural stands of Chrysanthemoides species, as well as other South African asteraceous plants, were monitored for E. osteospermi between 1992 and 2003. A morphological and molecular comparison of specimens referable to Endophyllum was undertaken. Based on these results, E. osteospermi was recorded on C. monilifera sspp. monilifera, pisifera, rotundata, canescens, and subcanescens, C. incana, and an undescribed taxon. E. osteospermi was also recorded on Osteospermum ciliatum, O. pollgaloides, and O. potbergense. Furthermore, a closely related but previously undescribed species, E. dimorphothecae sp. nov. is described on Dimorphotheca cuneata. Aecidium elytropappi is transferred to Endophyllum as E. elytropappi comb. nov., being recorded on Elytropappus rhinocerostis and Stoebe plumosa. This study shows that in South Africa E. osteospermi is restricted to a small group of related plant species in the Calenduleae. This rust is therefore considered suitable as a candidate agent for the biocontrol of C. monilifera ssp. monilifera, and pending the results of host specificity testing, would most likely be safe to introduce into Australia.