APPLICATION OF DNA TECHNOLOGY IN BREEDING PROTEACEOUS PLANTS

Since the development of a reliable DNA extraction method on ten genera of Proteaceae in 1994 by Maguire et al., considerable progress has been made in the application of DNA technology in breeding proteaceous plants. The research and application can be divided into the following areas: 1) DNA diversity studies for parent selection in breeding programmes, for systematics and for ecological characterisation. The research spins from the evaluation of different marker systems such as RAPD, ISSR, AFLP, SSR and sequences to the fingerprinting of species and cultivars, and identification of true hybrids; 2) characterisation of specific traits/genes for marker assisted selection in breeding. The specific traits studied include sex determination in Leucadendron, drought tolerance in Banksia, allergens, and antibacterial and antifungal traits/genes; 3) development of linkage maps for map-based marker identification and map-based cloning. The first such map in Proteaceae was developed in 2003 in macadamia by Peace et al. and we have recently developed a map in Grevillea with the aim to identify Phytophthora tolerance. Genetic modification has not been used widely in Proteaceae possibly because of limitations of a reliable regeneration system and availability of useful genes.