Genetic variation and structure of remnant stands of pohutukawa (Metrosideros excelsa, Myrtaceae)

AFLPs reveal an absence of geographical genetic structure among remnant populations of pohutukawa (Metrosideros excelsa, Myrtaceae)

“…This haplotype diversity is, however, shared by the different species of Metrosideros and Gardner et al (2004) suggested that this is a consequence of repeated hybridisation when the plants were confined together in the refugial regions. These results contrast with an earlier analysis of genetic structure in M. excelsa using five low diversity allozyme loci (Young et al 2001). This study showed high levels of genetic variation, comparable to levels seen in many other long-lived trees (Hamrick et al 1992), significant levels of inter-population variation, but an absence of any clear geographic genetic structure.…”

“…our previous studies using allozymes failed to find any clear relationship between genotypic variation and geography (Young et al 2001) and provide a contrast to the sequence-based studies using chloroplast dNA of Gardner et al (2004). Therefore, here we have used AFLP markers to analyse 10 of the original 20 populations used in the allozyme study of Young et al (2001) to see whether these markers that anonymously sample a large portion of the genome can provide a clearer picture of geographical patterns of genetic differentiation among remnant populations of pohutukawa.…”

“…1). These populations, which still cover most of the geographic range of the species, are a subset of those previously analysed using allozyme markers by Young et al (2001). open-pollinated seed were collected from up to 10 trees in each population.…”

“…The work of Young et al (2001) highlighted the significance of inter-population variation in pohutukawa for sourcing seed for revegetation programmes, providing support for the proposal that local seed be used to prevent genetic erosion of possibly locally adapted populations (department of Conservation 1996). When genetic differentiation among populations is strong, transfer of germplasm from one population to another may result in reduced vigour of the translocated material, compromising the success of restoration efforts.…”

“…Therefore, here we have used AFLP markers to analyse 10 of the original 20 populations used in the allozyme study of Young et al (2001) to see whether these markers that anonymously sample a large portion of the genome can provide a clearer picture of geographical patterns of genetic differentiation among remnant populations of pohutukawa.…”