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Spiraea japonica, a diverse, perennial shrubby species complex widespread across E Asia, was a useful model in a first attempt to link specific phylogeny, floristic evolution, and historical environmental changes in E Asia. DNA-based phylogenetic reconstruction served as a framework to investigate whether the patterns of variation in alkaloids and nrITS from varieties of S. japonica reflect the geological history of China and the uplifting of the Himalaya-Tibet plateau, the most significant geological event in E Asia since the late Paleocene. The high geographical structure found in the phylogenetic trees was corroborated by the distribution of alkaloids. All populations from E China, with mainly hetisine-type alkaloids, formed a single clade, sister to a clade of all populations from SW China, with mainly atisine-type alkaloids. The distribution boundary between the two clades roughly matched the floristic division between the Sino-Japanese Forest and the Sino-Himalayan Forest subkingdoms, as well as the environmental division between SW and E China, suggesting a close link between specific phylogeny, floristic evolution, and geographical changes in E Asia. The divergence between lineages at variety and population level within the eastern clade was slightly older than those within the southwestern clade, supporting the hypothesis of a northeast-southwest migration of Spiraea since the Eocene. The uplift of the Himalaya-Tibet plateau and subsequent increase in geographical complexity in SW China, could facilitate divergence maintenance, thus accelerating the evolutionary rate.

Microsatellite primers were developed to assess genetic diversity and population structure in Acer yangbiense, a critically endangered endemic species that occurs in northwestern Yunnan Province, China. •Using the Fast Isolation by AFLP of Sequences Containing repeats (FIASCO) protocol, 34 microsatellite loci were isolated and characterized in A. yangbiense. Polymorphisms were evaluated in 39 individuals from two distinct populations, one of which was naturally occurring and the other an ex situ grouping. Nine of the markers showed polymorphisms with two to five alleles per locus; observed (H(o)) and expected (H(e)) heterozygosities ranged from 0.0000 to 0.8000 and from 0.0000 to 0.6889, respectively. •These microsatellite primers will prove useful in the further investigation of population genetics studies in A. yangbiense and, in addition, will assist related research of other congeneric species.

Microsatellite primers were developed in the Chinese endangered and endemic orchid, Cymbidium tortisepalum, to investigate its genetic diversity and population genetic structure, and to identify its varieties.Using the Fast Isolation by AFLP of Sequences Containing repeats (FIASCO) protocol, 15 primer sets were identified in two wild populations. The number of alleles per locus ranged from two to six, with a mean of 3.5. The observed and expected heterozygosities varied from 0.250 to 0.917 and from 0.228 to 0.841, respectively. All of these primers successfully amplified in the congener C. goeringii, and 12 were found useful in C. faberi and C. sinense.These markers will facilitate further studies on the population genetics and molecular identification of C. tortisepalum, its varieties, and other congener species.

Microsatellite primers were developed for the important and popular ornamental spring orchid, Cymbidium goeringii, to investigate its genetic diversity and population genetic structure.Using the Fast Isolation by AFLP of Sequences Containing (FIASCO) repeats protocol, 15 primer sets were identified in two wild populations. The number of alleles per locus ranged from 2 to 5, with a mean of 3.3. The observed and expected heterozygosities varied from 0.167 to 0.917 and from 0.159 to 0.822, respectively. All these primers successfully amplified in the congener C. tortisepalum, and 12 primers were found useful in C. faberi and C. sinense.These markers will facilitate further studies on the population genetics of Cymbidium goeringii and other congeneric species.