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Fragmentation is generally considered to have negative impacts on widespread outbreeders but impacts on gene flow and diversity in patchy, naturally rare, self-compatible plant species remain unclear. We investigated diversity, gene flow and contemporary pollen-mediated gene immigration in the rare, narrowly distributed endemic shrub Calothamnus quadrifidus ssp. teretifolius. This taxon occurs in an internationally recognized biodiversity hotspot subjected to recent human-induced fragmentation and the condition of the remnants ranges from intact to highly degraded. Using microsatellites, we found that inbreeding, historically low gene flow and significant population differentiation have characterized the genetic system of C. quadrifidus ssp. teretifolius. Inbreeding arises from self-pollination, a small amount of biparental inbreeding and significant correlation of outcross paternity but fecundity was high suggesting populations might have purged their lethals. Paternity analyses show that pollinators can move pollen over degraded and intact habitat but populations in both intact and degraded remnants had few pollen parents per seed parent and low pollen immigration. Genetic diversity did not differ significantly between intact and degraded remnants but there were signs of genetic bottlenecks and reduced diversity in some degraded remnants. Overall, our study suggests human-induced fragmentation has not significantly changed the mating system, or pollen immigration to, remnant populations and therefore genetic connectivity need not be the highest conservation priority. Rather, for rare species adapted to higher levels of inbreeding, conservation efforts may be best directed to managing intact habitats and ecosystem processes. [ABSTRACT FROM AUTHOR]

Pollen dispersal was investigated in six populations of Calothamnus quadrifidus, a bird-pollinated shrub in the fragmented agricultural region of southern Western Australia. Paternity analysis using six microsatellite loci identified a pollen source within populations for 67% of seedlings, and the remainder were assumed to have arisen from pollen sources outside the populations. Outcrossing was variable, ranging from 5% to 82%, and long-distance pollen dispersal was observed in all populations with up to 43% of pollen sourced from outside the populations over distances of up to 5 km. This extensive pollen immigration was positively associated with population size but not isolation. Comparison of two populations of similar size but different density showed greater internal pollination and less selfing in the denser population, suggesting an influence of density on pollinator behaviour. The study revealed extensive long-distance pollen dispersal for C. quadrifidus within this fragmented agricultural landscape and highlighted the interaction between reserve populations and isolated road verge remnants in maintaining genetic connectivity at the landscape scale. [ABSTRACT FROM AUTHOR]

A genomic library was constructed and 13 polymorphic microsatellite markers were developed for Hakea oldfieldii, a woody shrub endemic to southwest Western Australia. Polymorphism was investigated for these markers in 28 individuals from a single population located in restricted habitat at the base of the Whicher Range south of Busselton. Expected heterozygosity ranged from 0.279 to 0.770 and averaged 0.633. Observed heterozygosity ranged from 0.321 to 0.786 and averaged 0.598. The number of alleles per locus ranged from 2.0 to 6.0 and averaged 4.5. These markers will be used to assay genetic diversity and pollen dispersal in this species. [ABSTRACT FROM AUTHOR]

A genomic library was constructed and 10 novel polymorphic microsatellite markers developed for Acacia saligna, a species complex being developed for agroforestry across southern Australia. Polymorphism was investigated for these markers in 30 individuals from two subspecies. Alleles per locus averaged 4.0 for ssp. saligna and 5.2 for ssp. lindleyi. Population specific alleles were detected for all loci. The microsatellite markers will be used for diagnostic assessment of the four main subspecies of the species complex. [ABSTRACT FROM AUTHOR]

Microsatellite loci were developed for genetic analysis of the bird pollinated woody shrub Calothamnus quadrifidus. A genomic library was constructed and screened with dinucleotide and trinucleotide repeat sequences. Ten dinucleotide microsatellite markers were developed, and polymorphism in a population of C. quadrifidus was investigated for six of these markers, which showed an average of 12.7 alleles per locus. Mendelian inheritance of the loci was confirmed through analysis of open pollinated progeny arrays of 10 plants. These loci will be used to study gene flow patterns between isolated populations of this species in southwest Western Australia. [ABSTRACT FROM AUTHOR]

A genomic library was constructed and 10 novel polymorphic microsatellite markers were developed for Banksia nivea subsp. uliginosa, a woody shrub endemic to the southwest of Western Australia. Polymorphism was investigated for these markers in 30 individuals from one population located in restricted habitat at the base of the Whicher Range east of Busselton. Expected heterozygosity ranged from 0.124 to 0.898 and averaged 0.570. Observed heterozygosity ranged from 0.133 to 0.933 and averaged 0.544. The number of alleles per locus ranged from 2.0 to 16.0 and averaged 7.3. These markers also produced amplification products in three other Banksia species and will be used to assay genetic diversity in these species. [ABSTRACT FROM AUTHOR]

The diadematid sea urchin Centrostephanus rodgersii occurs in Australia and New Zealand and has undergone recent southward range extension in Australia as a result of regional warming. Clarifying the population genetic structure of this species across its New Zealand range would allow a better understanding of recent and future mechanisms driving range changes in the species. Here, we use microsatellite DNA data to assess connectivity and genetic structure in 385 individuals from 14 locations across the Australian and New Zealand ranges of the species. We detected substantial genetic differentiation among C. rodgersii populations from Australia and New Zealand. However, the population from Port Stephens (located north of Newcastle), Australia, strongly clustered with New Zealand samples. This suggests that the New Zealand populations recently originated from this area, likely via larval transport in the Tasman Front flow that arises in this region. The weak population genetic structure and relatively low genetic diversity detected in New Zealand (global Fst = 0.0021) relative to Australia (global Fst = 0.0339) is consistent with the former population's inferred history of recent climate-driven expansion. Population-level inbreeding is low in most populations, but were higher in New Zealand (global Fis = 0.0833) than in Australia (global Fis = 0.0202), suggesting that self-recruitment is playing an increasingly important role in the New Zealand region. Our results suggest that C. rodgersii is likely to spread southwards as ocean temperatures increase; therefore, it is crucial that researchers develop a clearer understanding of how New Zealand ecosystems will be reshaped by this species (and others) under climate change. [ABSTRACT FROM AUTHOR]

Microsatellite markers were developed for the Australian bird-pollinated woody shrub Banksia sphaerocarpa var. caesia to study gene flow among populations in a highly fragmented landscape. Eight loci were developed, and in a sample of 40 individuals from one population, the number of alleles per locus ranged from five to 21 and observed heterozygosities ranged from 0.385 to 0.914. All eight loci showed independent inheritance. Analysis of open-pollinated progeny arrays confirmed Mendelian inheritance at seven loci, while null alleles were suspected at the remaining locus. [ABSTRACT FROM AUTHOR]

We developed 20 polymorphic nuclear microsatellites from Pinus pinaster using genomic libraries enriched with repeated motifs. A total of 25 individuals from five different populations were used to estimate genetic diversity parameters. [ABSTRACT FROM AUTHOR]