The complete chloroplast genome sequence of Platanthera minor.

Platanthera minor is widely distributed in East Asia. The complete circular chloroplast genome with a length of 154,430 bp possesses the typical structure, consisting of a large single copy (LSC) of 83,536 bp, a small single copy (SSC) of 17,612 bp, and two inverted repeats (IR) of 26,641 bp. The average GC content of the genome is 36.7%. The circular P. minor chloroplast genome contains 114 genes, including 80 protein-coding genes, four rRNA genes, and 30 tRNA genes. The chloroplast sequence provided a resource for analyzing genetic diversity of the Orchidaceae family.

Development and characterization of polymorphic microsatellite markers in Dysosma pleiantha (Berberidaceae).

PREMISE OF THE STUDY: The development of compound microsatellite markers was conducted in Dysosma pleiantha to investigate genetic diversity and population genetic structure of this threatened medicinal plant. METHODS AND RESULTS: Using the compound microsatellite marker technique, 14 microsatellite markers that were successfully amplified showed polymorphism when tested on 38 individuals from three populations in eastern China. Overall, the number of alleles per locus ranged from 2 to 14, with an average of 7.71 alleles per locus. CONCLUSIONS: These results indicate that these microsatellite markers are adequate for detecting and characterizing population genetic structure and genetic diversity in Dysosma pleiantha.

Genetic structure and breeding system of a rare understory herb, Dysosma versipellis (Berberidaceae), from temperate deciduous forests in China.

To evaluate the role of Quaternary refugial isolation in allopatric (incipient) speciation of East Asian temperate forest biotas, we analyzed amplified fragment length polymorphisms (AFLPs) and the breeding system in Dysosma versipellis. The study revealed that D. versipellis is mostly self-incompatible, genetically highly subdivided and depauperate at the population level (e.g., Φ(ST) = 0.572/H(E) = 0.083), and characterized by a low pollen-to-seed migration ratio (r ≈ 4.0). The latter outcome likely reflects limited pollen flow in a low-seed disperser whose hypothesized "sapromyophilous" flowers undergo scarce, inefficient, and likely specialized cross-pollination by small Anoplodera beetles, rather than carrion flies as assumed previously. In consequence, fruit set in D. versipellis was strongly pollen-limited. Our AFLP data support the hypothesis of a long-standing cessation of gene flow between western and central eastern populations, consistent with previous chloroplast DNA data. This phylogeographic pattern supports the role of the Sichuan Basin as a floristic boundary separating the Sino-Himalayan vs. Sino-Japanese Forest subkingdoms. Our genetic data of D. versipellis also imply that temperate deciduous forest elements to the west and the east of this basin responded differently to Quaternary climate change, which may have triggered or is leading to allopatric (incipient) speciation.

Did glacials and/or interglacials promote allopatric incipient speciation in East Asian temperate plants? Phylogeographic and coalescent analyses on refugial isolation and divergence in Dysosma versipellis.

To explore the evolutionary consequences of climate-induced fluctuations in presently fragmented temperate forest habitats in continental East Asia we investigated the phylogeography and demographic history of the temperate-deciduous forest endemic Dysosma versipellis from disjunct montane sites in Central-Southeast China. Based on a survey of chloroplast (cp) DNA sequence variation, our analyses show that this perennial herb consists of morphologically indistinguishable western and central/eastern cpDNA lineages. Coalescent analyses under the 'isolation with migration' (IM) model support an ancient (Mid-Pleistocene) divergence between these lineages, with the western lineage having persisted without significant population growth in a long-term refuge just east of the Tibetan (Qinghai-Xizang) Plateau. In contrast, for the central/eastern lineage, we found strong evidence for population expansion from a refuge located south of the middle and lower reaches of the Yangtze River, and likely coinciding with the last or penultimate interglacial, followed by considerable population isolation and divergence in situ over (at least) the latest glacial-interglacial cycle. In line with recent evidence from palaeomodeling of East Asian forest biomes, our results suggest that the same vicariance factor, i.e. climate-induced eco-geographic isolation through (a)biotic displacement of temperate-deciduous forested habitats, promoted the divergence of D. versipellis lineages and populations at different spatial-temporal scales and over glacial and interglacial periods. Thus, there is no evidence that populations of D. versipellis merged at lower elevations during the last glacial(s). As such, D. versipellis accords with the premise that Late Quaternary refugial isolation is likely to have enhanced allopatric (incipient) species formation of temperate plants in East Asia.