Comparison of genetic variability in remnant and wide-spread rainforest understorey species of Austromyrtus (Myrtaceae)
- Cite this article as:
- Shapcott, A. & Playford, J. Biodivers Conserv (1996) 5: 881. doi:10.1007/BF00054740
This study investigated the genetic variability, stand structure, and reproductive activity of four species of Austromyrtus which showed differing levels of rarity and patterns of distribution. The focus of the study was A. gonoclada which is extremely rare due to extensive urban expansion in Brisbane, Australia. The total number of known individuals in the species is only 27. Because nothing was known about the genetic structure of Austromyrtus comparison with other species was made to provide a context for studies on A. gonoclada. Population structure and levels of reproductive activity were not correlated to species rarity or distribution. A. gonoclada showed maximum genetic variability in comparison to the other species of Austromyrtus, despite the small population size. Three of six variable loci were in Hardy-Weinberg equilibrium in A. gonoclada populations, in contrast to populations of the other species which had few heterozygous genotypes. The higher variability of the remaining individuals is suggested to be a legacy of the relatively short time since they were part of a larger population. There were very few seedlings of A. gonoclada, in contrast to the other species of Austromyrtus and the seeds produced fell from the tree while still green and were unable to be germinated. A. gonoclada is under continuing threat from development and has low reproductive success. Active programmes for recovery of this species will be necessary as its continued survival is dependent on population increase. Management of the genetic resources of the species will enable survival with long-term evolutionary potential.