Abstract

Background and aims

Temperate forests are disjunct in the Northern Hemisphere, having become fragmented from the earlier widespread (Tertiary) boreotropical forest. We asked ‘What are the contemporary patterns of population variation in ecological traits of a Tertiary relict in a macroecological context?’. This issue underpins our understanding of variation in populations occurring in the same biome but on different continents.

Methodology

We examined characters associated with root and shoot emergences among populations of Viburnum opulus in temperate forests of Asia, North America and Europe. This species has complex seedling emergence extending over several years and requiring various temperature cues.

Principal results

Populations varied in germination responses and clustered into groups that were only partly related to varietal status. Whereas roots (at warm temperatures) and shoots (following a cold period) simultaneously emerged from seeds of all populations when simulated dispersal occurred in winter, they were delayed in some populations when dispersal occurred in summer.

Conclusions

Viburnum opulus populations, some separated by 10 300 km, showed high similarity in seedling development and in germination phenology, and we suggest that stabilizing selection has played a key role in maintaining similar dormancy mechanisms. Nevertheless, there was some degree of variation in other germination characters, suggesting local adaptation.

Details

Title
Seed germination and seedling development ecology in world-wide populations of a circumboreal Tertiary relict
Author
Karlsson, Laila M 1 ; Milberg, Per 1 ; Hidayati, Siti N 2 ; Kondo, Tetsuya 3 

 IFM Biology, Division of Ecology, Linköping University, SE-581 83 Linköping, Sweden; Department of Crop Production Ecology, Swedish University of Agricultural Sciences, Box 7043, 750 07 Uppsala, Sweden 
 Department of Biology, Middle Tennessee State University, Murfreesboro, TN 37132, USA 
 Graduate School of Agriculture, Hokkaido University, Kita-ku, Sapporo, Hokkaido 060-8589, Japan 
Publication year
2012
Publication date
2012
Publisher
Oxford University Press
e-ISSN
20412851
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
3170680471
Copyright
Published by Oxford University Press. This work is published under http://creativecommons.org/licenses/by-nc/3.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.