Northern leaf blight is a lethal foliar disease of maize caused by the fungus Exserohilum turcicum. The aim of this study was to elucidate the infection strategy of the fungus in maize leaves using modern microscopy techniques and to understand better the hemibiotrophic lifestyle of E. turcicum. Leaf samples were collected from inoculated B73 maize plants at 1, 4, 9, 11, 14 and 18 days post‐inoculation (dpi). Samples were prepared according to standard microscopy procedures and analysed using light microscopy as well as scanning (SEM) and transmission electron microscopy (TEM). Microscopic observations were preceded by macroscopic observations for each time point. The fungus penetrated the leaf epidermal cells at 1 dpi and the disease was characterized by chlorotic leaf flecks. At 4 dpi the chlorotic flecks enlarged to form spots, and at 9 dpi hyphae were seen in the epidermal cells surrounding the infection site. At 11 dpi lesions started to form on the leaves and SEM revealed the presence of hyphae in the vascular bundles. At 14 dpi the xylem was almost completely blocked by hyphal growth. Hyphae spread into the adjacent bundle sheath cells causing cellular damage, characterized by plasmolysis, at 18 dpi and conidiophores formed through the stomata. Morphologically, lesions started to enlarge and coalesce leading to wilting of leaves. This study provides an updated, detailed view of the infection strategy of E. turcicum in maize and supports previous findings that E. turcicum follows a hemibiotrophic lifestyle.

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communities situated 0.1-3 km apart show significant turnover and may be tied to ecological niches). Insects show a similar pattern, but the decrease in community overlap is more gradual, suggesting many insects can utilize multiple (possibly closely related) hosts while plants are tied to particular niches. The emergent structure of multiple interaction networks is spatially and temporally invariant, despite high compositional change. However, the internal structure of the networks shows variation (i.e. interactions show spatial and temporal turnover). Seasonal interaction turnover is driven by a turnover in herbivores and by herbivore host switching. Spatially the turnover in interactions is driven by simultaneous turnover in both plants and insects, either suggesting that insects are host specific, or that both groups exhibit parallel responses to environmental gradients. Spatial interaction turnover is also driven by a turnover in plants, showing that many insects can utilize multiple (possibly closely related) hosts and have wider distribution ranges than their host plants. Results point toward insect host specificity, but probably not at the species level, as the primary mechanism structuring insect communities associated with the Restionaceae in the CFR.An ethnobotanical survey of plants used for treatment of common ailments in Lesotho was undertaken by interviewing 27 traditional medicine practitioners (TMPs) in the Maseru district. A total of 38 ailments were reported as commonly treated using a total of 80 medicinal plants. The 10 commonest ailments in descending order are: tuberculosis (TB), human immunodeficiency virus (HIV), herpes, liver problems, breast cancer, diabetes mellitus, syphilis, infertility, stomach disorders, and difficult pregnancy/labor. The ailments were ranked according to frequency mentioned in interviews, and TB was found to be the commonest ailment mentioned by all the interviewees. The aim of this presentation is therefore to 1) discuss the plants used by TMPs in Lesotho for the treatment of TB and 2) present the results of a literature survey conducted to determine if these plants (i) are used for similar purposes elsewhere and (ii) have been tested for antimicrobial properties against Mycobacterium tuberculosis to validate their traditional utilization. Of the 80 plants mentioned in the study, 26 were recorded as being used for the treatment of TB, both individually and in combination. The plants used individually include; Leobordea lanceolata, Pentanisia prunelloides, Dicoma anomala, Helichrysum odoratissimum, Helichrysum caespititium, Elephantorrhiza elephantina, Hypoxis hermerocallidea, Eriocephalus punctulatus, Trifolium burchellianum and Gazania krebsiana. The first five plants are also used in combination together with Withania somnifera and Pennisetum salvifolia in one herbal preparation.