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Although revegetation activities are often accompanied by extensive release of translocated or cultivated individuals into natural communities, their potential effects on native populations are relatively unclear. Understanding the original genetic structures in natural habitats and how the patterns have been maintained in populations at revegetation sites is a critical first step in assessing current revegetation efforts. Artemisia indica var. maximowiczii is a native species commonly used for revegetation in Japan. We assessed the genetic and morphological variations in individuals collected from natural habitats and revegetation sites across Japan, as well as individuals have grown from two types of commercial seeds from China used for revegetation: imported seeds that originated from Chinese populations and reimported seeds that originated from Japanese populations but were cultivated in China. Genome‐wide single nucleotide polymorphism (SNP) data revealed that individuals collected from natural habitats were genetically differentiated between northeastern and southwestern regions in Japan. Individuals grown from the reimported seeds were genetically similar to the northeastern populations in Japan, suggesting their original sources were areas in the northeast. Most individuals collected from revegetation sites were genetically similar to individuals from the reimported seeds, even though the revegetation sites were in southwestern Japan, suggesting that seeds derived from the northeastern populations were used for revegetation throughout Japan. Individuals grown from the imported seeds that originated from China were genetically and morphologically differentiated from native individuals in Japan. Careful consideration should be given to the extensive use of non‐local seeds for revegetation that is sourced only from northeastern Japan or foreign countries. [ABSTRACT FROM AUTHOR]

Premise: Divergent selection due to environmental heterogeneity can lead to local adaptation. However, the ecological and evolutionary processes of local adaptation that occurs across multiple regions are often unknown. Our previous studies reported on the ecotypic divergence within a local area of variation of Potentilla matsumurae, an alpine herb adapted to the fellfield–snowbed environment. Here we investigated large‐scale geographic patterns of ecotypic differentiation in this species to infer local adaptation and selective forces across multiple regions. Methods: We compiled information on the overall distributions of fellfield and snowbed habitats on the mountains in Japan across the distribution of the species. Next, we conducted common garden experiments to test the adaptive divergence of the fellfield–snowbed plants derived from multiple regions. Finally, we evaluated phylogeographic structures based on cpDNA and allozyme variations and inferred the evolutionary history of ecotype differentiation. Results: The mosaic distribution of the fellfield–snowbed ecotypes across isolated mountaintops constitutes indirect evidence for habitat‐specific natural selection. The significant difference in survivorship between the ecotypes observed in a controlled snow environment provides more substantial evidence of local selection. Phylogeographic structures support the hypothesis that ecotypic divergence events from fellfield to snowbed populations occurred independently in at least two distinct regions. Conclusions: Ecotypic divergence of P. matsumurae has occurred across a series of mountain sky islands. Local selection in snowy environments is a driving force that maintains the divergent ecotypes across multiple mountain regions and can contribute to the diversification of plants in heavy‐snow regions. [ABSTRACT FROM AUTHOR]

We examined the seed-germination responses of 27 alpine species with reference to habitat type (fellfield and snowbed), temperature (five regimes), and light requirement. About 70% of species showed>40% germination at warm temperatures without cold stratification. However, a moist-chilling treatment markedly improved the germination percentages in most species, especially under cool conditions. Thus, cold stratification effectively reduced the temperature requirement for germination. Patterns of germination response within species were not consistent between the fellfield and snowbed habitats for species inhabiting both habitats. For interspecific comparisons, there were no significant differences in germination responses to the temperature regimes and the cold stratification between the fellfield and snowbed species. Also, germination speed and the length of germinating period did not differ between fellfield and snowbed species. Most species (86%) showed a requirement for light for germination without cold stratification. Although the extent of the light requirement was reduced after cold stratification in some species, the light requirement of most small-seeded species remained. The combination of cold stratification and the light requirement is a major factor determining the seedling emergence and formation of seed banks in alpine plants. However, habitat-specific patterns of germination traits were less clear, suggesting similar germination traits in fellfield and snowbed plants, at least under controlled conditions in the laboratory. [ABSTRACT FROM AUTHOR]