Aspen Bibliography
Document Type
Article
Journal/Book Title/Conference
Ecology and Evolution
Volume
9
Issue
14
Publisher
John Wiley & Sons Ltd.
First Page
8062
Last Page
8074
Publication Date
6-25-2019
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Abstract
Aim
We assessed the vulnerability of an isolated, relictual Pleistocene hybrid aspen population of conservation interest (Populus x. smithii ) and the nearest populations of its parent species (Populus grandidentata and Populus tremuloides ) to springtime post‐bud break freezing and growing season drought stress. Response to these stressors in the three taxa was compared in terms of avoidance and tolerance.
Location
North American Midwest; USA.
Methods
Unique genets from the hybrid Niobrara River population and from the two parental populations were propagated in a common garden from rhizome cuttings. We tracked their phenology before and after bud break and measured their vulnerability to freezing (stem electrolyte leakage and leaf chlorophyll fluorescence) and to drought (stem hydraulic conductance, leaf osmotic potential, stomatal pore index, and gas exchange).
Results
Populus grandidentata was slower to leaf out, showed lower vulnerability to stem freezing and drought‐induced cavitation, but exhibited a lower capacity to tolerate drought stress through leaf resistance traits compared to P. tremuloides . Hybrids were similar to P. grandidentata in their overwintering strategy, exhibiting later bud break, and in their higher resistance to stem freezing damage, but they were more similar to P. tremuloides in their higher vulnerability to drought‐induced cavitation. The hybrids shared various leaf‐level gas exchange traits with both parents. All aspens showed limited loss of leaf photosynthetic function following moderate freezing.
Main Conclusions
The Niobrara River hybrid population is vulnerable to drought due to its combination of inherited drought avoidance and tolerance traits. As climate changes, P. x smithii will likely suffer from increased drought stress, while being unaffected by frost during warmer springs. The two parental species contrast in their survival mechanisms in response to climatic stress, with P. tremuloides tending toward freezing tolerance but drought avoidance and P. grandidentata tending toward freezing avoidance and drought tolerance.
Recommended Citation
Deacon, NJ, Grossman, JJ, Cavender‐Bares, J. Drought and freezing vulnerability of the isolated hybrid aspen Populus x smithii relative to its parental species, P. tremuloides and P. grandidentata . Ecol Evol. 2019; 9: 8062– 8074. https://doi.org/10.1002/ece3.5364
Included in
Agriculture Commons, Ecology and Evolutionary Biology Commons, Forest Sciences Commons, Genetics and Genomics Commons, Plant Sciences Commons