A survey of the reproductive ecology and patterns of pollen-mediated gene flow in Eucalyptus camaldulensis and E.leucoxylon paddock trees.

Abstract

In many areas of south-eastern Australia, the clearance of temperate eucalypt woodlands for agriculture has been so extensive that only scattered remnant trees remain. The loss of habitat and increased spatial isolation of trees in paddocks is predicted to lead to a decline in plant fecundity because of disruptions to plant-pollinator interactions, which has important implications for the long-term persistence and maintenance of these populations. In order to assess the ability of paddock trees to contribute to population regeneration, this study assessed the reproductive viability and patterns of mating of paddock trees of two woodland species, Eucalyptus camaldulensis and E.leucoxylon in the Mt. Lofty Ranges, South Australia. This study revealed that paddock tree populations of E. camaldulensis and E.leucoxylon were reproductively viable and received sufficient visits by pollinators that resulted in high outcrossing rates. The results suggest that seed collected from these paddock trees are both genetically diverse and representative of adult populations. Therefore, such trees could contribute successfully to conservation strategies that sought to regenerate cleared paddocks.