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ABSTRACT: Fourteen polymorphic microsatellite markers were developed and characterized in Schisandra chinensis, a widely used traditional Chinese herbal medicine. The average number of alleles of these microsatellites was 6.071, ranging
from 2 to 12 per locus. The effective number of alleles was from 1.645 to 7.119 per locus with an average of 3.916. The observed
and expected heterozygosity were 0.107–0.871 and 0.399–0.874, respectively. Three loci significantly (P<0.01) deviated from Hardy–Weinberg equilibrium. No significant (P<0.01) linkage disequilibrium was detected for any pair of loci. Eleven out of 14 SSRs are also polymorphic in S.sphenanthera, a closely related medicinal species of S.chinensis. This set of microsatellite markers has provided a useful tool for the ongoing efforts in studying the population genetic
variation of S.chinensis and S.sphenanthera, which will facilitate formulation of appropriate strategies for conservation and sustainable utilization of the two important
officinal species.
Conservation Genetics Resources 04/2012; 1(1):119-121. · 0.49 Impact Factor
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ABSTRACT: A set of cpSSR markers were developed for the tree genus Liriodendron L. to investigate population genetic structure and phylogeographic history.
Primers were designed directly from the chloroplast genome sequences of Liriodendron tulipifera. Among the 55 cpSSR markers tested, 11 polymorphic markers were identified in L. tulipifera. The number of alleles in the population tested ranged from two to five, and the unbiased haploid diversity per locus ranged from 0.074 to 0.644. Eighteen primer pairs generated polymorphic amplification in L. chinense. The number of alleles per locus ranged from two to seven, and the unbiased haploid diversity per locus was from 0.250 to 0.964.
cpSSR markers developed here will be useful for phylogeography and population genetics studies of Liriodendron.
American Journal of Botany 05/2011; 98(5):e123-6. · 2.66 Impact Factor
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ABSTRACT: • Premise of the study: Michelia maudiae is a threatened species in the Magnoliaceae. Microsatellite markers were developed and characterized in M. maudiae for further investigation of its conservation genetics. • Methods and Results: Microsatellite markers were developed in M. maudiae using the Fast Isolation by AFLP of Sequences Containing Repeats protocol. Ten polymorphic microsatellites were assessed in two populations of M. maudiae. The number of alleles detected per locus varied from 1 to 8. Observed and expected heterozygosities ranged from 0.000 to 0.792 and from 0.000 to 0.826, respectively. Six primer pairs showed transferability in the two related species Michelia foveolata and Michelia chapensis. • Conclusions: This set of microsatellite markers provides a useful tool for future studies of the conservation genetics of M. maudiae and other congeneric species.
American Journal of Botany 12/2010; 97(12):e157-8. · 2.66 Impact Factor
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ABSTRACT: The SMART switching mechanism at 5' end of the RNA transcript technique was used to construct a cDNA library from inner pericarp of the red flesh kiwifruit Actinidia chinesis cv 'Hongyang'. Construction of cDNA library facilitated cloning of the genes associated with the secondary metabolism, the specific genes in the course of anthocyanin biosynthesis. The titers of the primary library and the amplified library were 6.7x104 cfu/mL and 2.72x108 cfu/mL, respectively. The recom-bination rate was over 99.8%. The lengths of most cDNAs in the library ranged from 700 bp to 1 000 bp. A total of 1 014 clones randomly chosen from the cDNA library were sequenced and these expressed sequence tags (ESTs) were analyzed. A set of 963 sequences were obtained. Clustering and assembly of these cDNA sequences resulted in 632 unigenes, includ-ing 92 contigs and 540 singletons. Among them, 441 EST unigenes were predicted to have known functions. Gene AcF3H, which participated in anthocyanin biosynthesis from sequencing, was obtained. The length of the AcF3H cDNA was 1 369 bp (GenBank accession No: FJ542819). Bioinformatic analysis showed that AcF3H ORF region was 1 101 bp, which en-coded a peptide with 366 amino acids. The amino acid sequences of this gene shared extensive homology to Arabidopsis, Vitis, and Eustoma. The expression of AcF3H was investigated in inner pericarp of 'Hongyang' at six stages during fruit development using RT-PCR. The expression level was high before colour-changed stage, and then decreased at the primary stage of pigmentation.
Hereditas (Beijing) 12/2009; 31(12):1265-72.
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ABSTRACT: For endangered plants interspecific hybridization occurring in ex situ collections may lead to failure of reintroduction actions. We used Sinojackia xylocarpa, a well documented Chinese endemic species that is extinct in the wild, as a model case to address this concern. We used paternity analyses to assess the spontaneous hybridization and patterns of pollen flow between S. xylocarpa and its congener species, S. rehderiana, in conserved populations in Wuhan Botanic Garden. Interspecific hybridization events were detected in seven out of eight maternal trees of S. xylocarpa, and an average of 32.7% seeds collected from maternal trees of S. xylocarpa were hybrids. The paternity of 93 out of 249 seedlings from S. xylocarpa assigned to S. rehderiana provided convincing evidence that spontaneous interspecific hybridization occurred extensively in the living garden collection we studied. Different patterns of pollen dispersal (predominantly short-distance vs. long-distance pollination) were observed between intra- and interspecific hybridization events in the garden. Pollen dispersal within the ex situ populations was not restricted by distance, as evidenced by a lack of significant correlations between the average effective pollen dispersal distance (delta) and the geographic distances (d1 and d2) between maternal and paternal trees. The interspecific pollen-dispersal distance ranged from 10 to 620.1 m (mean 294.4 m). Such extensive hybridization in ex situ collections could jeopardize the genetic integrity of endangered species and irrevocably contaminate the gene pool if such hybrids are used for reintroduction and restoration. We recommend strongly that measures be taken to minimize the genetic risks of this kind of hybridization, including establishing buffer zones in ex situ collections, manipulating flowering phenology, testing seed lots before use in reintroduction programs, and controlling pollination for seed purity.
Conservation Biology 11/2009; 24(1):246-55. · 4.69 Impact Factor
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ABSTRACT: Molecular population genetics is not only one of the most important subjects of evolutionary biology, but also the basics subject of breeding, association mapping, and linkage analysis. Molecular population genetics has been developed from the classical population genetics aiming at studying population genetic structure and the factors that affect the population genetic structure by investigating the variation of DNA sequences. Therefore, population evolving history can be deduced accurately and quantitatively for evaluating the former conclusions about long-term evolution and the stability of genetic systems. Thus, molecular population genetics can avoid the shortcomings of classical population genetics, i.e. limiting to deduce the short evolving history of a population. Moreover, understanding of molecular variation patterns leads to further evaluation of the evolution theory, which is based on "Natural Selection" and introduced by Darwin. Molecular population genetics has made great progress and revealed many important scientific issues, such as the pattern of DNA polymorphism, the level of linkage disequilibrium, demographical history, and the genetic forces affecting gene evolvement. Furthermore, new research areas have been developed from molecular population genetics and become the hot fields, such as molecular phylogeography. In this review, we summarized studies and progresses of plant molecular population genetics.
Hereditas (Beijing) 11/2007; 29(10):1191-8.
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ABSTRACT: Spontaneous hybridization in ex situ facilities can undermine the genetic integrity of ex situ collections and potentially contaminate open-pollinated seeds or seedlings destined for the reintroduction of endangered plant species into the wild. In the present study, the potential risk of hybridization between two endangered Chinese endemic species, namely Sinojackia xylocarpa Hu and S. rehderiana Hu, which are naturally allopatric species but were conserved ex situ in Wuhan Botanical Garden (WBG), Wuhan, China, were investigated over three consecutive years from 2003 to 2005. The entire overlapping flowering period of the two species was 14–20 d and the two species shared the same pollinator insects during the entire flowering season in WBG. The floral isolation between the two species was not an issue in the ex situ collection at WBG. The results suggest an opportunity for pollen transfer between species and a potential risk of genetic introgression and loss of genetic identity of open-pollinated seeds produced in the ex situ collection of these two endangered species. An artificial reciprocal cross between S. xylocarpa and S. rehderiana confirmed that the two congener species could readily set seeds, indicating no post-pollination barriers to hybridization and the importance of spatial isolation as a barrier to inter-specific crossing. Therefore, to manage these crossable species with overlapping flowering times and shared pollination vectors in ex situ facilities, spatial isolation should be carefully considered to minimize the possibility of spontaneous hybridization.(Managing editor: Wei Wang)
Journal of Integrative Plant Biology 07/2006; 48(7):867 - 872. · 2.53 Impact Factor
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ABSTRACT: The desert legume genus Ammopiptanthus comprises two currently endangered species, A. mongolicus and A. nanus. Genetic variability and genetic differentiation between the two species and within each species were examined.
Inter-simple sequence repeat (ISSR) marker data were obtained and analysed with respect to genetic diversity, structure and gene flow.
Despite the morphological similarity between A. mongolicus and A. nanus, the two species are genetically distinct from each other, indicated by 63 % species-specific bands. Low genetic variability was detected for both population level (Shannon indices of diversity Hpop = 0.106, percentage of polymorphic loci P = 18.55 % for A. mongolicus; Hpop = 0.070, P = 12.24 % for A. nanus) and species level (Hsp = 0.1832, P = 39.39 % for A. mongolicus; Hsp = 0.1026, P = 25.89 % for A. nanus). Moderate genetic differentiation was found based on different measures (AMOVA PhiST and Hickory B) in both A. mongolicus (0.3743-0.3744) and A. nanus (0.2162-0.2369).
The significant genetic difference between the two species might be due to a possible vicariant evolutionary event from a single common ancestor through the fragmentation of their common ancestor's range. Conservation strategies for these two endangered species are proposed.
Annals of Botany 05/2005; 95(5):843-51. · 4.03 Impact Factor
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ABSTRACT: Conserving genetic diversity of rare and endangered species and their evolutionary potential is one of the long-term goals of ex-situ conservation. Some potential genetic risks in ex-situ conservation in botanical gardens are presented. The preserved species may lack genetic representativity because of poor sampling. Inappropriate plantations, inadequate records and unclear kinships jeopardize endangered species to genetic confusion, inbreeding depression or outbreeding depression. Artificial selection and habitat conversion also potentially result endangered plants in adapting to ex-situ conservation, which had been usually overlooked. All the genetic risks can decrease the success of reintroduction and recovery. Therefore, appropriate genetic management should be carried out in botanical gardens to decrease or avoid genetic risks in ex-situ conservation.
Hereditas (Beijing) 02/2005; 27(1):160-6.
