Abstract of a paper based on work funded in part by the Australian Flora Foundation.

The diversity of arbuscular mycorrhizas of selected Australian Fabaceae
Mark Tibbett1, Megan H. Ryan1,2,3, Susan J. Barker2, Yinglong Chen1,2, Matthew D. Denton2,3,4, Tamara Edmonds-Tibbett2,3,& Christopher Walker1,5
1Centre for Land Rehabilitation, School of Earth and Geographical Science, University of Western Australia, Australia
2School of Plant Biology, University of Western Australia, Australia
3Future Farm Industries CRC, University of Western Australia, Australia
4Rutherglen Centre, Department of Primary Industries, Victoria, Australia
5Royal Botanic Gardens, Edinburgh, UK
Plant Biosystems (2008), Vol. 142, No. 2, pp. 420–427    Grant details

Abstract
Members of the Australian native perennial Fabaceae have been little explored with regard to their root biology and the role
played by arbuscular mycorrhizal (AM) fungi in their establishment, nutrition and long-term health. The ultimate goal of our
research is to determine the dependency of native perennial legumes on their co-evolved AM fungi and conversely, the
impact of AM fungal species in agricultural fields on the productivity of sown native perennial legume pastures. In this paper
we investigate the colonisation morphology in roots and the AMF, identified by spores extracted from rhizosphere soil, from
three replicate plots of each of the native legumes, Cullen australasicum, C. tenax and Lotus australis and the exotic legumes L.
pedunculatus and Medicago sativa. The plants were grown in an agricultural field. The level and density of colonisation by AM
fungi, and the frequency of intraradical and extraradical hyphae, arbuscules, intraradical spores and hyphal coils all differed
between host plants and did not consistently differ between native and exotic species. However, there were strong similarities
between species in the same genus. The three dominant species of AM fungi in rhizosphere soil also differed with host plant,
but one fungus (Glomus mosseae) was always the most dominant. Sub-dominant AM species were the same between species
in the same genus. No consistent differences in dominant spores were observed between the exotic and native Fabaceae
species. Our results suggest that plant host influences the mycorrhizal community in the rhizosphere soil and that structural
and functional differences in the symbiosis may occur at the plant genus level, not the species level or due to provenance.