Into the range: a latitudinal gradient or a center-margins differentiation of ecological strategies in Arabidopsis thaliana?

Abstract

Background and Aims: Determining within-species large-scale variation in phenotypic traits is central to elucidate the drivers of species ranges. Intraspecific comparisons offer the opportunity to understand how trade-offs and biogeographical history constrain adaptation to contrasted environmental conditions. Here we test whether functional traits, ecological strategies and phenotypic plasticity in response to abiotic stress vary along a latitudinal or a center- margins gradient within the native range of Arabidopsis thaliana. Methods: The phenotypic outcomes of plant adaptation at the center and margins of its geographic range were experimentally examined in 30 accessions from southern, central and northern Europe. The variation of traits related to stress tolerance, resource use, colonization ability as well as survival and fecundity was determined in response to high temperature (34C) or frost (- 6C), in combination with response to water deficit. Key Results: Both evidence for a latitudinal and a center-margins differentiation was found. Traits related to the acquisitive/conservative strategy trade-off varied along a latitudinal gradient. Northern accessions presented a greater survival to stress than central and southern accessions. Traits related to a colonization-competition trade-off followed a center-margin differentiation. Central accessions presented a higher phenotypic plasticity and trait values associated with a higher colonization ability than northern and southern accessions which instead had a higher competition ability. Conclusions: Intraspecific phenotypic variation helps us understand how the distribution range has evolved in Arabidopsis thaliana, which is shaped both by climate and the population migratory history. We advocate to consider intraspecific trait variation in species range studies instead of species means only as classically done in macroecology.

Locally adaptive temperature response of vegetative growth in Arabidopsis thaliana

“…Indeed, accessions originating from colder environments show increased freezing tolerance upon cold acclimation (49–52). This fits with observations of northern and colder regions favoring slower growing, more stress-tolerant plants (3, 4). Also biogeographic studies in A. thaliana found that winter temperatures are a major determinant of suitable habitats for this species (53–55).…”

“…These strategies have evolved to maximize fitness, but are constrained by trade-offs between components such as growth, survival and reproduction (1, 2). While most life-history studies investigate differences between species, there is also variation found within species, including in Arabidopsis thaliana , where life-history variation has been linked to climate parameters (3–5). Less clear is how trade-offs are shaping this variation.…”

Climate biogeography ofArabidopsis thaliana:linking distribution models and individual variation

“…In Arabidopsis, DeLeo et al (2020) found region-specific decadal shifts in phenology and physiology in herbarium specimens. Public seed banks house great diversity from across species ranges that can also be used to study the geography of natural variation (Estarague et al, 2021; Scholl et al, 2000). Here we use individual-level performance estimates from museum specimens and life history variation in natural seedbank accessions to interrogate predictions from fitted distribution models.…”

A Perspective on Plant Phenomics: Coupling Deep Learning and Near-Infrared Spectroscopy

“… Plant survival has two categories (dead or alive), which were measured according to the protocol described in Estarague et al (2021) . Genotypes have 10 categories corresponding to the 10 natural accessions used here.…”

“…To further explore the potential of NIRS as a predictive tool of plant stress level, we used experimental data included in our database ( Supplementary Material ) from 30 genotypes of Arabidopsis thaliana subjected to water deficit combined with either high or low (freezing) temperatures ( Estarague et al, 2021 ). All plant individuals were measured for leaf NIRS in the course of the treatment, and survival was visually recorded after the treatment.…”