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This content will become publicly available on April 11, 2023

Title: Genotypic variation and plasticity in climate-adaptive traits after range expansion and fragmentation of red spruce ( Picea rubens Sarg.)
Shifting range limits are predicted for many species as the climate warms. However, the rapid pace of climate change will challenge the natural dispersal capacity of long-lived, sessile organisms such as forest trees. Adaptive responses of populations will, therefore, depend on levels of genetic variation and plasticity for climate-responsive traits, which likely vary across the range due to expansion history and current patterns of selection. Here, we study levels of genetic and plastic variation for phenology and growth traits in populations of red spruce ( Picea rubens ), from the range core to the highly fragmented trailing edge. We measured more than 5000 offspring sampled from three genetically distinct regions (core, margin and edge) grown in three common gardens replicated along a latitudinal gradient. Genetic variation in phenology and growth showed low to moderate heritability and differentiation among regions, suggesting some potential to respond to selection. Phenology traits were highly plastic, but this plasticity was generally neutral or maladaptive in the effect on growth, revealing a potential liability under warmer climates. These results suggest future climate adaptation will depend on the regional availability of genetic variation in red spruce and provide a resource for the design and management of assisted more » gene flow. This article is part of the theme issue ‘Species’ ranges in the face of changing environments (Part II)’. « less
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Award ID(s):
1655344 1656099 1735316
Publication Date:
Journal Name:
Philosophical Transactions of the Royal Society B: Biological Sciences
Sponsoring Org:
National Science Foundation
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