Plasticity in leaf hydraulic architecture varies among genotypes and populations of Populus fremontii

Garthwaite, Iris Jean-Elyse (2022) Plasticity in leaf hydraulic architecture varies among genotypes and populations of Populus fremontii. Masters thesis, Northern Arizona University.

Text Garthwaite_2022_plasticity_leaf_hydraulic_architecture_varies_among_ge.pdf - Published Version Download (1MB)

Abstract

Climate means, extremes, and variability are shifting rapidly, which will continue to result in mismatches between climate and locally adapted plant traits. Phenotypic plasticity, the ability of a plant to respond to environmental conditions within a lifetime (e.g., by adjusting the traits of leaves they make each year), may provide a buffer for plants to persist under rapid environmental change. We used three common gardens situated across a temperature gradient to investigate phenotypic plasticity in six populations of Fremont cottonwood (Populus fremontii), an important riparian tree, collected from across a naturally occurring temperature gradient. We focused on the plasticity of leaf venation, a multivariate trait that is linked to plant performance and tolerance of environmental stress. We found that 1) Populations responded differently to a hotter growing environment, with some increasing and some decreasing the density of their leaf venation; 2) Within populations, vein density also differed among genotypes in the hottest growing environment; 3) Locally adapted southern populations trended toward greater vein density and higher growth in the hottest growing environment compared to northern populations. Past studies indicate that high vein density is associated with a suite of characteristics that are likely to support survival in hotter and drier climates (i.e., high leaf hydraulic conductance, high stomatal density, and drought resistance). Results from this study suggest that different P. fremontii populations will vary in their capacity to adjust their leaf venation and support growth in hot environments. Survivorship modeling efforts, restoration project managers, and assisted migration initiatives should consider genetic stock, growing conditions, and multiple dimensions of environmental stress early in the research and planning process to improve predictions and enhance restoration outcomes.

Item Type:	Thesis (Masters)
Publisher’s Statement:	© Copyright is held by the author. Digital access to this material is made possible by the Cline Library, Northern Arizona University. Further transmission, reproduction or presentation of protected items is prohibited except with permission of the author.
Keywords:	Fremont cottonwood, Leaf hydraulic architecture, Climate change, Phenootopic plasticity, Adaptability
Subjects:	Q Science > QK Botany
NAU Depositing Author Academic Status:	Student
Department/Unit:	Graduate College > Theses and Dissertations College of the Environment, Forestry, and Natural Sciences > School of Earth Sciences and Environmental Sustainability
Date Deposited:	07 Nov 2022 22:32
Last Modified:	25 May 2024 08:30
URI:	https://openknowledge.nau.edu/id/eprint/5869

Actions (login required)

IR Staff Record View

Downloads