Multi‐trait genetic variation in resource‐use strategies and phenotypic plasticity correlates with local climate across the range of a Mediterranean oak (Quercus faginea)

Abstract

Resource-use strategies are hypothesized to evolve along climatic gradients. However, our understanding of the environmental factors driving divergent evolution of resource-use strategies and the relationship between trait genetic variation and phenotypic plasticity is far from complete. Using the Mediterranean tree Quercus faginea as study system, we tested the hypothesis that a conservative resource-use strategy with increased drought tolerance and reduced phenotypic plasticity has evolved in areas with longer and more severe dry seasons.We conducted a glasshouse experiment in which we measured leaf morphological, physiological, growth and allocation traits in seedlings from 10 range-wide climatically contrasting populations, grown under two different watering treatments.Both univariate and multivariate analyses revealed a genetic gradient of resource-use strategies and phenotypic plasticity associated with provenance climate. In particular, populations from harsher (drier and colder) environments had more sclerophyllous leaves, lower growth rates, better physiological performance under dry conditions and reduced multi-trait phenotypic plasticity compared to populations from more mesic and milder environments.Our results suggest that contrasting precipitation and temperature regimes play an important role in the adaptive intraspecific evolution of multivariate phenotypes and their plasticity, resulting in coordinated morphology, physiology, growth and allometry according to alternative resource-use strategies.

Characterization, costs, cues and future perspectives of phenotypic plasticity

“…multidimensional plasticity), the molecular mechanisms, adaptive value for fitness and its implications for evolution may vary compared to plasticity in response to a single environmental factor. For example, in Mediterranean oak, precipitation and temperature regimes play an important role in the evolution and expression of coordinated multivariate phenotypic plasticity in several morphological traits ( Sole-Medina et al , 2022 ). Multidimensional plasticity cannot be interpreted by simply scaling up univariate plasticity to more environments as these interactions often result in unexpected expression of plasticity.…”

Climatic variations along an aridity gradient drive significant trait intraspecific variability in Mediterranean species

“…At the same time, the Mediterranean region shows a very high environmental heterogeneity, offering a wide range of climatic variations at a local scale (Lionello et al ., 2006). Consistently with trait-based economic spectrum models, populations of Mediterranean species tend to adopt conservative acquisition strategies when inhabiting more xeric habitats, while populations in more mesic environments are rewarded by acquisitive strategies (Solé-Medina et al ., 2022). The dichotomy between conservative and acquisitive resource uptake strategies is also reflected in BTV, with conservative species appearing more drought resistant and showing more ITV than acquisitive species (Rodríguez-Alarcón et al ., 2022).…”

“…An important issue of studies embracing trait-based approaches is that they mainly focus on interspecific, or between-species, variability (BTV) (Albert et al ., 2011; Funk et al ., 2017). This can be relevant as, albeit often being a lesser driver of variability, several evidence suggests a significant effect of intraspecific variability (ITV) on several ecological processes (Albert et al ., 2011; Puglielli et al ., 2022) such as disease resistance (Garrett et al ., 2009), decomposition rates (Lecerf and Chauvet, 2008), community assemblies (Cornwell et al ., 2008; Jung et al ., 2010) and response to precipitation and temperature (Jung et al ., 2014; Solé-Medina et al ., 2022; Rodríguez-Alarcón et al ., 2022).…”

Parallel Differentiation and Plastic Adjustment of Leaf Anatomy in Alpine Arabidopsis arenosa Ecotypes

“…Furthermore, high levels of phenotypic plasticity can also be inherently costly, and thus maladaptive [ 44 , 45 ]. Indeed, adaptive, maladaptive and neutral consequences of plasticity have been reported [ 46 , 47 , 48 , 49 , 50 ]. The role of phenotypic plasticity in the course of evolution is also under debate.…”