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地球科学::海洋科学::海洋生物学 5	植物学 2	生物学 2
生物学::生态学::种群生态学 2	Conservation genetics of L. decora: The nucleotide sequences from three chloroplast DNA (cpDNA) regions (the rpl16 intron, trnQ-5’rps16 intergenic spacer and rpl32-trnL intergenic spacer) and two nuclear gene (GAPDH and GBSSI) were selected to characterize the genetic structure and phylogeography of this species. Eleven populations were sampled across the distribution range of L. decora in China. Low levels of cpDNA genetic diversity were found in this species and within populations, with the identification of 2 haplotypes in a total of 2745 bp (cpDNA: π = 0.00102, Hd = 0.468, HT = 0.480), while the levels of genetic diversity revealed by the nuclear gene GAPDH and GBSSI (GAPDH: π = 0.00237, Hd = 0.773, HT = 0.807; GBSSI: π = 0.00167, Hd = 0.751, HT = 0.790) were relatively high, indicating that random losses of genetic polymorphisms from populations may have occurred recently. Relatively high genetic differentiation for both markers (cpDNA: GST = 0.899, FST = 0.893; GAPDH: GST = 0.309, FST = 0.432; GBSSI: GST = 0.274, FST = 0.263) were detected at the wide-species level. Two cpDNA haplotypes, twelve GAPDH haplotypes and ten GBSSI haplotypes were recovered, respectively. Almost every population except the population SP was fixed for one cpDNA haplotype, causing no variation within the populations. Several nuclear haplotypes were distributed widely in most populations. These results may be mainly explained by long-term fragmentation and the limited gene flow caused by geographic isolation among populations. The mismatch distribution analyses and neutrality tests provided no evidence for a recent population expansion in L. decora. The time of all GAPDH haplotypes coalesced to the most recent common ancestor was dated to between 0.46 (95% CI 0.14-0.89)-0.65 (95% CI 0.18-1.22)mya, which predates the LGM. In situ shrinking or extinction might have occurred to L. decora during the glacial ages and L. decora populations did not retreat to common refugia or migrated backwards. Based on the genetic diversity and uniqueness of the populations, conservation strategies are discussed for this endangered species.2. 1	地球科学::海洋科学 1
环境生物学 1	生物学::植物学::植物生态学 1	生物学::植物学::植物生理学 1

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