Regional genetic structure and environmental variables influence our conservation approach for feather heads (Ptilotus macrocephalus)

Continued alterations to the Australian environment compromise the long-term viability of many plant species. We investigate the population genetics of Ptilotus macrocephalus a perennial herb that occurs in two nationally endangered communities on the Victorian Volcanic Plain Bioregion (VVP), Australia, to answer key questions regarding regional differentiation and to guide conservation strategies. We evaluate genetic structure and diversity within and among 17 P. macrocephalus populations from 3 regions of southeastern Australia using 17 microsatellite markers developed de novo. Genetic structure was present in P. macrocephalus between the three regions but not at the population level. Environmental factors, namely temperature and precipitation, significantly explained differentiation between the North region and the other two regions indicating isolation by environment. Within regions, genetic structure currently shows a high level of gene flow and genetic variation. Our results sugge...