Isolation and characterization of microsatellite loci in <Emphasis Type="Italic">Cryptocarya chinensis</Emphasis> in lower subtropical China

We report on the isolation and characterization of eight microsatellite markers from repetitive DNA enriched libraries for Cryptocarya chinensis from lower subtropical China. These are the first microsatellite loci reported for Cryptocarya species. The number of alleles ranged from three to nine. Observed and expected heterozygosities ranged from 0.0518 to 0.9910 and 0.5241 to 0.7935 for polymorphic loci, respectively. These markers will allow analyses of the baseline genetic variability and population structure of C. chinensis to enrich our scientific understanding of forest fragmentation on genetic health of this species and provide strategies for effective conservation and management in this area.     

Isolation and characterization of polymorphic microsatellite markers in <Emphasis Type="Italic">Cupressus </Emphasis><Emphasis Type="Italic">chenggiana</Emphasis> S. Y. Hu (Cupressaceae)

Cupressus chenggiana S. Y. Hu (Cupressaceae) is an endemic and endangered conifer species in southwest China. In order to study the population genetics and design the effective conservation methods, we aimed to develop microsatellite primers for this species in the present study. We developed eight new microsatellite loci for this species through biotin capture method. Polymorphism of each locus was further assessed in 18 individuals from three geographically distant populations. The number of alleles per locus ranged from 6 to 11 with an average of 8.13. The observed and expected heterozygosities ranged from 0.219 to 0.296 and from 0.374 to 0.470, with averages of 0.254 and 0.417, respectively. We further found that three of nine microsatellite loci developed previously for another congeneric species showed polymorphic banding patters. We performed primer-crossing tests of these loci in the other two congeneric species which are closely related to C. chenggiana (C. gigantea and C. duclouxiana). These microsatellite markers would be effective for analyzing genetic diversity and population genetic structure of this species and its morphological differentiation with the close relatives.     

Development of ten microsatellite loci for <Emphasis Type="Italic">Gentiana crassicaulis</Emphasis> (Gentianaceae)

Genetiana crassicaulis is one of famous Chinese medicinal plant. The over-collection for its root has caused its dramatic reduction. In order to devise adequate conservation and management strategies for this species, it is important to characterize its genetic diversity and understand its population structure. Here, 10 polymorphic microsatellite markers have been developed. AC/TG microsatellite was enriched by combining biotin capture method. Polymorphism of each locus was assessed in 30 individuals from six populations. The number of alleles ranged from 2 to 9 and the expected heterozygosity ranged from 0.32 to 0.78.     

Development of microsatellite markers for <Emphasis Type="Italic">Echinops setifer</Emphasis> (Asteraceae), an endangered grassland plant species in Japan

Echinops setifer is an endangered grassland plant species in Japan. We isolated and characterized nine microsatellite loci in this species. The number of alleles ranged from 3 to 7 and expected heterozygosities from 0.108 to 0.761. These markers described here will be useful for investigating the genetic diversity, genetic structure and gene flow, and planning for conservation of E. setifer.     

Development of microsatellite markers for <Emphasis Type="Italic">Metrosideros boninensis</Emphasis> (Myrtaceae), an endangered endemic plant species from the Bonin Islands,Japan

Metrosideros boninensis is an endangered endemic plant species from the Bonin Islands. We isolated and characterized nine microsatellite loci in this species. The expected heterozygosities of these nine markers ranged from 0.127 to 0.768. These markers described here will be useful for investigating the genetic diversity, genetic structure and gene flow, and planning for conservation of M. boninensis.     

Isolation and characterization of eight polymorphic microsatellite loci for the critically endangered Arenaria nevadensis (Caryophyllaceae)

We report on the isolation and characterization of eight microsatellite markers from enriched libraries for Arenaria nevadensis, one of the most critically endangered plant species in the Iberian Peninsula. These are the first microsatellite loci reported for Arenaria species. The number of alleles ranged from two to eight, and the expected heterozygosity from 0.067 to 0.873. These markers will be useful for characterizing the genetic diversity in A. nevadensis and understanding its population structure, and will provide important genetic data for the conservation and recovery of this species.     

Microsatellite DNA loci from the typical halophyte <Emphasis Type="Italic">Thellungiella salsuginea</Emphasis> (Brassicaceae)

Thellungiella salsuginea (Brassiaceae) is a typical halophyte which can tolerate extreme cold, drought, and salinity. In order to understand the adaptive evolution of this species in the arid habitats, it is important to know its genetic structure. In this study, 17 polymorphic microsatellite loci were isolated and characterized from an enrichment genomic library of this species. We further assessed the polymorphisms of each locus in 18 individuals from nine geographically distant populations. The number of alleles per locus ranged from six to fourteen. The observed and expected heterozygosity ranged from 0.17 to 0.28 and 0.32 to 0.45, respectively. These markers have been crossly checked in another congeneric species, T. halophila. These microsatellite markers will be useful for investigating population genetics and adaptive evolution of this species and morphological divergence between and it and the closely related species.     

Isolation and characterization of twelve novel microsatellite loci in the ark shell <Emphasis Type="Italic">Scapharca broughtonii</Emphasis>

Scapharca broughtonii is an over-exploited bivalve in China. In order to promote a conservation program for this species, it is necessary to evaluate its genetic diversity and population genetics. For this purpose, we isolated twelve novel polymorphic microsatellite markers and examined their allelic variation using 40 wild individuals collected from one locality along the Chinese coast. The number of alleles ranged from 2 to 22 per locus with the expected heterozygosities ranging from 0.444 to 0.944. These markers will be useful for the assessment of genetic variation for this species.     

Microsatellite analysis of genetic diversity in the Chinese alligator (<Emphasis Type="Italic">Alligator sinensis</Emphasis>) Changxing captive population

Chinese alligator (Alligator sinensis) is a critically endangered species endemic to China. In this study, the extent of genetic variation in the captive alligators of the Changxing Reserve Center was investigated using microsatellite markers derived from American alligators. Out of 22 loci employed, 21 were successfully amplified in the Chinese alligator. Sequence analysis showed loci in American alligators had a bigger average size than that of the Chinese alligators and the longest allele of an individual locus almost always existed in the species with longer stretch of repeat units. Eight of the 22 loci were found to be polymorphic with a total of 26 alleles present among 32 animals scored, yielding an average of 3.25 alleles per polymorphic locus. The expected heterozygosity (H _E) ranged at a moderate level from 0.4385 to 0.7163 in this population. Compared to that in the American alligators, a lower level of microsatellite diversity existed in the Changxing population as revealed by about 46% fewer alleles per locus and smaller H _E at the homologous loci. The average exclusion power and the ability to detect shared genotypes and multiple paternity were evaluated for those markers. Results suggested that when the polymorphic loci were combined, they could be sensitive markers in genetic diversity study and relatedness inference within the Chinese alligator populations. The level of genetic diversity present in the current Changxing population indicated an important resource to complement reintroductions based on the individuals from the other population. In addition, the microsatellite markers and their associated diversity characterized in this population could be utilized to further investigate the genetic status of this species.     

A set of microsatellite markers for use in the endangered sea urchin <Emphasis Type="Italic">Strongylocentrotus nudus</Emphasis> developed from <Emphasis Type="Italic">S. purpuratus</Emphasis> ESTs

The first set of nine microsatellite markers for the endangered sea urchin Strongylocentrotus nudus was developed from EST databases of S. purpuratus. Number of alleles per locus ranged from two to thirteen. The observed and expected heterozygosities ranged from 0.000 to 0.645 and from 0.063 to 0.912, respectively. These informative microsatellite markers will be useful in studies of population genetic structure for this species.     

Isolation and characterization of microsatellite DNA primers in Juniperus przewalskii Kom (Cupressaceae)

Juniperus przewalskii (Cupressaceae) is a dominant tree species endemic to the northeast Qinghai-Tibetan Plateau. This species plays an important role in maintaining the arid ecosystem in this region. However, natural distributions of this species have been declined. In order to develop effective conservation methods, it is important to know the distribution of the genetic diversity within and among populations. In this study, we developed nine new microsatellite loci for this species. We used the combining biotin capture method to enrich AG/CT/AC/GGT microsatellites. The polymorphisms of each locus were further assessed in 12 individuals from four geographically distant populations. The number of alleles per locus varied from three to six and expected heterozygosity ranged from 0.58 to 0.70. These loci together provide a useful tool to investigate the genetic diversity of this species. In addition, all markers have been crossly checked in the other four congeneric species.     

Isolation and characterization of microsatellite loci in Ostryopsis davidiana (Betulaceae)

Ostryopsis (Betulaceae) is a samll genus endemic to China with only two species. Both of them play an important role in restoring the local ecosystems. The distribution of genetic diversity between and within populations in each species are important to further utilize the wild genetic resources and explore the interspecific divergence. In this study, we developed 10 microsatellite loci from O. davidiana by the combining biotin capture method for the first time. A total of 27 microsatellite sequences were recovered through screening the library and 10 of them are polymorphic. The number of alleles per locus in 18 sampled individuals ranged from 3 to 6, expected heterozygosity and observed heterozygosity ranged from 0.2958 to 0.4767 and from 0.1591 to 0.2997, respectively. In addition, all markers have been crossly checked in the other congeneric species. These microsatellite markers would together provide a useful tool for investigating the genetic diversity and structure of both species and speciation mechanism between them.     

Microsatellite DNA loci from the drought desert plant Calligonum mongolicum Turcz. (Polygonaceae)

Calligonum mongolicum Turcz. (Polygonaceae) is a typical drought desert plant which can tolerate extreme drought, cold, and other stress in the northern extreme drought desert of China. They are playing an important role in maintaining the local ecosystems in these regions. In order to understand the adaptive evolution and develop effective conservation methods of this species in the arid habitats, it is important to know its genetic structure. In this study, 14 polymorphic microsatellite loci were isolated and characterized from an enrichment genomic library of this species. We further assessed the polymorphisms of each locus in 18 individuals from six geographically distant populations. The number of alleles per locus ranged from three to six. The observed and expected heterozygosity ranged from 0.24 to 0.35 and 0.38 to 0.57, respectively. These markers have been crossed checked in another congeneric species, C. mongolicum. These microsatellite markers will be useful for investigating the genetic structure and devising conservation strategies of this species, and morphological divergence between and it and the closely related species.     

Development and characterization of ten novel microsatellite markers from olive ridley sea turtle (Lepidochelys olivacea)

Olive ridleys, one of the widely distributed marine turtle species has undergone declines in recent years due to multiple anthropogenic factors warranting conservation efforts for which assessment of genetic variability in existing populations become critical. Here we describe development of ten new microsatellite markers from a short sequence repeat-enriched partial genomic DNA library, which are found to be highly informative for genetic studies. Eight of these markers when tested on 83 olive ridley turtles revealed high allelic diversity (4–27 alleles per marker), and high observed and expected heterozygosity estimates that ranged from 0.29 to 0.82 and 0.62 to 0.94, respectively. Two microsatellites were monomorphic in the tested olive ridley samples, but were found to be informative/polymorphic when tested on related marine turtle species. More importantly, nine of the new markers showed robust cross-species amplifications in three related species Dermochelys coriacea, Chelonia mydas and Eretmochelys imbricata. Thus, this study describes ten new microsatellite markers and also demonstrates their potential as efficient genetic markers in studies related to parentage analysis, population structure, phylogeography and species relationships of olive ridleys and other marine turtle species.     

Development and characterization of microsatellite loci in Chinese medicinal plant Akebia trifoliate ssp. australis and cross-species amplification in closely related taxa

Eleven polymorphic microsatellite loci were isolated and characterized from an AC-enriched genomic library of Akebia trifoliate ssp. australis. The number of allele per locus ranged from 3 to 14. The observed heterozygosity and expected heterozygosity at population level were 0.196–1.000 and 0.522–0.902, respectively. In addition, this set of microsatellites produced robust cross-species amplification in other two related taxa, suggesting these microsatellite markers should provide a useful tool for genetic and conservation studies of the Akebia species.     

Development of 10 polymorphic microsatellite loci primers for Codonopsis pilosula Nannf. (Campanulaceae)

Codonopsis pilosula Nannf., as an important traditional Chinese medicinal plant species, has been used to treat fatigue, thirst and loss of appetite. In this study, we developed 10 new microsatellite loci primers from the genome of this species using the combined biotin capture method. The polymorphism of each locus was further assessed through 27 individuals from four geographically distant populations. The number of alleles per locus ranged from 6 to 11. The observed and expected heterozygosity ranged from 0.15 to 0.24 and 0.27 to 0.40, respectively. We further performed cross-priming tests of these loci in the other three congeneric species. These microsatellite markers will be useful for investigating genetic diversity within and between populations of these species.     

Isolation and characterization of microsatellite loci in the endangered freshwater fish <Emphasis Type="Italic">Pararasbora moltrechti</Emphasis> (Cyprinidae) using PCR-based isolation of microsatellite arrays (PIMA)

Pararasbora moltrechti (Cyprinidae) is an endangered freshwater fish with a scattered distribution in the central Taiwan. In order to undertake a conservation program for this species in Taiwan, it is essential to evaluate its genetic diversity and population structure. For this purpose, we described the development of eight microsatellite loci in P. moltrechti for genetic studies. These new molecular markers were tested in 36 individuals of the rare species. The number of alleles per locus ranged from 8 to 14. As the expected heterozygosity varied from 0.770 to 0.932, all microsatellite loci, however, were significantly deviated from Hardy–Weinberg expectations due to the heterozygote deficiency. Hung-Du Lin and Teh-Wang Lee contributed equally.     

Isolation and characterization of microsatellite loci of Lycopodium fordii Bak. (Lycopodiaceae, Pteridophyta)

Lycopodium fordii Bak. (Lycopodiaceae, Pteridophyta) is a gardening plant with a native, fragmentary distribution in Taiwan. In this study, we described the development of eleven microsatellite loci in L. fordii for genetic studies. These new markers were tested in 16 individuals of three populations. The number of alleles ranged from 1 to 5 and the expected heterozygosity from 0.41746 to 0.72222. Four of the nine polymorphic loci were significantly deviated from Hardy-Weinberg expectations due to the heterozygote deficiency. The microsatellite markers have also been proved as informative genetic markers for other 15 Lycopodium species.     

Characterization of microsatellite loci for the Amazonian rummy‐nose tetra,Hemigrammus bleheri (Teleostei,Characidae)

The rummy‐nose tetra, Hemigrammus bleheri, is a small fish found in forest streams of the Rio Negro floodplain, central Amazonia. This species is popular in aquaria and used as an ornamental fishery resource by the riverine people from middle Rio Negro. Here we describe eight microsatellite DNA loci for rummy‐nose tetras. Number of alleles and heterozygosity per locus in a sample of 30 fish ranged from five to 22 and from 0.52 to 0.96, respectively. These highly variable genetic markers provide important tools for investigating population history and identifying conservation units in rummy‐nose tetras.     

Development of a set of highly polymorphic genomic microsatellites (gSSRs) in Sitka spruce (Picea sitchensis (Bong.) Carr.)

Robust, polymorphic microsatellite DNA markers (simple sequence repeats—SSRs) are valuable tools for a range of tree conservation and breeding applications. SSRs are routinely used in the study of population genetic structure and diversity, pedigree reconstruction and genetic linkage mapping. Their abundance in the genome, co-dominant inheritance and potential for cross-species amplification make microsatellites highly prized markers. This paper characterises 22 novel genomic polymorphic microsatellite loci for Sitka spruce (Picea sitchensis (Bong.) Carr.). Amplification of DNA from Sitka spruce material was carried out both with a set of unrelated trees to obtain diversity statistics for each locus, and with the progeny of a full-sib family to test simple Mendelian inheritance. Observed heterozygosity ranged from 0.38 to 0.91 and allele number per locus ranged from 6 to 21, with a mean of 12.2. In addition, the primer pairs were tested with DNA from Norway spruce (P. abies) and white spruce (P. glauca) to investigate their potential for cross-species amplification and ten loci amplified in all three species. The results from these genomic microsatellites are compared to data generated from microsatellites derived from Picea EST libraries. In summary, this novel, highly polymorphic markers represent a significant addition to the rapidly expanding Picea genomics tool-box. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.