XVI International Botanical Congess

Nuytsia floribunda, is one of three monotypic genera of root hemiparasites in the mistletoe family Loranthaceae. Nuytsia roots are attached to those of a wide range of hosts covering extensive areas by their unique root-severing haustoria and extensive networks of underground rhizomes and roots. Development of the haustorial connection between roots of host and parasite is described including a proposed apoplastic pathway of host xylem solutes into the haustorial parent root. Significantly lower parasite xylem potentials provide a driving force for such solute flow and transfer of both labelled N and an unusual, naturally occurring amino acid from associated hosts is demonstrated. These effective nutrient gathering mechanisms allow Nuytsia to survive in the nutrient poor heathlands of SW Australia.