My contributions to science and its impact
Phytophthora species are amongst the most destructive plant pathogens and yet relatively little is known regarding their global diversity. Although Phytophthora species have a worldwide distribution, relatively few species have been reported from Africa, and the majority of these have been reported from South Africa. In South Africa, Phytophthora species are known to affect agricultural crops, native forests, plantations, and orchards of non-native species. The severity of Phytophthora diseases varies greatly within South Africa, depending on the area and crop being planted. My research contributes toward understanding the diversity of Phytophthora species in South Africa associated with plantations and orchards of non-native trees and native forests along with screening for disease-resistant genotypes for commercial forestry and orchards.
The Orchidaceae is one of the largest and most diverse angiosperm families. However, orchid diversity is rapidly declining due to over-exploitation and habitat destruction. Orchids have non-endospermous seeds lacking nutrients for seedling development. They, therefore, require mutualistic associations with mycorrhizal fungi that promote seed germination and nourish the developing seedling. At maturity, mycorrhizae also help the plants to absorb nutrients from the substrate. Therefore, orchid mycorrhizal interactions are important for the survival of orchids in natural habitats. The diversity of the mycorrhizae associated with orchids is poorly documented and only a few studies have been conducted to identify and characterize these fungi. My study contributes to capturing the mycorrhizal diversity of South African orchids, through identification and characterization of the orchid mycorrhizae associated with the South African endemic and endangered orchid.