Contrasting Patterns of Clonality in Two Closely Related Mallee Species from Western Australia, Eucalyptus argutifolia and E. obtusiflora (Myrtaceae)

Abstract

Allozymes were used to investigate patterns of clonal growth (vegetativespread) in two closely related multi-stemmed (mallee) eucalypts from WesternAustralia.Eucalyptus argutifolia Grayling & Brooker,a rare species with a localised distribution, appeared to be extensivelyclonal. Several populations had putative clones larger than 100m², with the largest clone size estimated to be 306m². By contrast, the more common and widespreadE. obtusiflora DC. was far less clonal and had a maximumclone size of 22 m². Both genetic and environmentalfactors may have contributed to these contrasting patterns of clonal growth.When clonality is taken into account, most populations ofE. argutifolia had very few individuals (≤ 12 genets)and estimates from this study suggest that the entire species may consist ofless than 500 genets.