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Premise of the Study: Much research has focused on plant responses to ongoing climate change, but there is relatively little information about how climate change will affect the early plant life history stages. Understanding how global warming and changes in winter snow pattern will affect seed germination and seedling establishment is crucial for predicting future alpine population and vegetation dynamics. Methods: In a 2‐year study, we tested how warming and alteration in the snowmelt regime, both in isolation and combination, influence seedling emergence phenology, first‐year growth, biomass allocation, and survival of four native alpine perennial herbs on the southeastern Tibetan Plateau. Key Results: Warming promoted seedling emergence phenology of all four species and biomass per plant of two species but reduced seedling survival of three species. Prolonged snow cover partly mediated the affects of warming on Primula alpicola (survival and biomass), Pedicularis fletcheri (phenology, biomass, and root:shoot ratio) and Meconopsis integrifolia (survival). For the narrowly distributed species M. racemosa, seedling growth was additively decreased by warming and prolonged snow cover. Conclusions: Both warming and alteration of the snow cover regime can influence plant recruitment by affecting seedling phenology, growth, and survival, and the effects are largely species‐specific. Thus, climate change is likely to affect population dynamics and community structure of the alpine ecosystem. This is the first experimental demonstration of the phenological advancement of seedling emergence in the field by simulated climate warming. [ABSTRACT FROM AUTHOR]

• Premise of the study: Little is known about the effect of environmental conditions on seed dormancy break at the community level or how it could be affected by climate change. This study tested the effects of storage conditions on germination of 489 species from high-elevation natural grasslands on the Tibet Plateau. • Methods: We stored seeds in dry cold, dry warm, and wet cold environments to test the effect of these conditions on germination. Germination responses were classified with the use of cluster analysis. The effect of phylogeny on germination response to storage conditions was determined. • Key results: Compared with results of wet cold conditions, storing seeds at dry warm or dry cold conditions decreased the mean community germination percentage by 17.93% and 16.07%, respectively. Storing seeds at dry warm vs. dry cold conditions decreased the community mean germination percentage by 4.61%. The germination response to moisture conditions during storage showed significant phylogenetic patterns, whereas the germination response to storage temperature did not. On the basis of the germinability of seeds of the same species stored under different conditions, germination may increase, decrease, or stay the same. • Conclusions: Within the high-elevation Tibetan grassland community, the different responses in dormancy breaking and germination behavior to the same storage conditions may have implications for understanding how this community might respond to climate change, in particular, some species may increase in the community, whereas others may decrease or remain the same. However, the potential for such change can be detected only by studying the responses of many species. [ABSTRACT FROM AUTHOR]

We report a new kind of seed dormancy and identify the storage behavior category for an important understory rainforest tree that also is used as an ornamental. While studying seed dormancy of Fabaceae species in Sri Lanka, we observed a considerable delay in emergence of the plumule following radicle emergence in Humboldtia laurifolia. Because epicotyl dormancy has not been reported in Fabaceae, we undertook a detailed morphological study of seed germination in this species. Our aims were to document desiccation tolerance/intolerance and epicotyl dormancy in seeds of H. laurifolia. Drying and low temperature storage were used to evaluate storage behavior of the seeds and imbibition, germination, and seed coat anatomy to categorize seed dormancy in two seed collections. Plumule development before its emergence and effects of light and temperature on plumule emergence were monitored. All seeds that were dried to 15% moisture content or stored at -1°C lost viability. Plumules began to grow 20 ± 5 d from radicle emergence and emerged after 40 ± 3 d. Dark and high illuminance further delayed plumule emergence. Seeds are recalcitrant and have a hitherto unreported kind of epicotyl dormancy, for which we propose the formula Cnd (root) - Cplb (epicotyl). [ABSTRACT FROM AUTHOR]