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Muola, A.

Publications and source records attributed to Muola, A..

4 recordsLinked to original sources

Context-dependent selection and genetic facilitation and constraint on rosette diameter and herbivore resistance across european outdoor common gardens under ambient and reduced precipitation in Fragaria vesca

The expression of plant defensive traits against herbivores often incurs costs to other essential functions, such as growth and reproduction. Understanding how selection acts on putatively functional traits that are expected to trade off across space and time is therefore critical for predicting evolutionary responses to ongoing and future environmental change. Here, we used multiple replicated genotypes of woodland strawberry (Fragaria vesca; Rosaceae) grown over two years in three outdoor common gardens in Spain, Belgium, and Sweden. In each garden, genotypes were exposed to both a reduced-precipitation treatment simulating drought and an ambient precipitation treatment. We estimated directional and correlational selection on rosette diameter (a proxy for growth) and herbivore resistance (measured as the inverse of chewing damage) using fruit and stolon production as proxies for sexual and asexual fitness across all environments (i.e., every site x year x treatment combination). We then combined selection gradients with environment-specific genetic (co)variance among genotypes to quantify the expected response to selection ({Delta}z = G{beta}) and to identify covariance-driven constraints or facilitation therein. Selection consistently favored larger rosette diameter for both fitness proxies across nearly all environments, which, in combination with genetic covariances among genotypes, resulted in a general evolutionary response toward increased rosette diameter, with the strongest response at the wettest site (Belgium). In contrast, selection on resistance and the corresponding among-genotype evolutionary responses were strongly context-dependent. Correlational selection on rosette diameter x resistance occurred in only a few environments, primarily under reduced precipitation. Environment-dependent genetic covariances constrained or facilitated selection on both traits only at the site with the highest herbivory (Sweden) under drought conditions. Overall, our results reveal a context-dependent interplay between selection and genetic architecture, underlining the difficulty of predicting evolutionary trajectories under environmental change, and highlighting how spatially and temporally variable conditions may maintain standing genetic variation in plant traits.

evolutionary biology↗

Variation in phenotypic plasticity of metabolic and performance traits along a latitudinal gradient in Woodland Strawberry

Phenotypic plasticity and local adaptation jointly determine plant responses to environmental variation, yet their relative contributions and evolutionary interactions remain poorly understood. We grew fifteen woodland strawberry (Fragaria vesca) genotypes from a European latitudinal gradient in four common gardens for two years, quantifying primary metabolites and biomass, reproduction and herbivore damage-related traits. Considering all measured traits combined, environment explained the largest variance (30%), followed by genotype-by-environment interactions (18%) and genotype effects (9%), indicating substantial heritable plasticity. However, plasticity was not uniform: northern genotypes showed greater plasticity in stress metabolites like succinic acid but more canalized growth traits, whereas southern genotypes maintained constitutively high protective metabolite levels. Latitude explained 4.4% of plasticity profile variation. Phenotypic variation was consistently better explained by long-term temperature than precipitation at the site of origin across all trait groups under study. Our results indicate that plasticity itself is an evolved, trait-specific characteristic shaped by climatic gradients, challenging simple hierarchies of trait lability. Significance StatementWe studied wild strawberries from across Europe and discovered that populations from different regions have evolved distinct adaptive strategies to cope with their local cli-mates. These differences highlight the remarkable diversity of plant solutions to environmental challenges. Understanding these natural adaptations could help us breed strawberries or other plant organisms better suited to future climate conditions.

ecology↗

Tolerance to land-use changes through natural modulations of the plant microbiome

Land-use changes pose a threat to many ecosystems and are a major driver of species loss. Adaptations to altered environments or migration to more suitable habitats are potential mechanisms to resist global change, which can, however, lag behind rapid anthropogenic alterations of the environment. Our data show that rapid natural modulations of the plant microbiome in response to land-use change directly affect plant phenotype and performance, and thus increase plant tolerance to environmental changes. In a common garden experiment, the effects of the microbiome on the plant phenotype were stronger than the direct effects of fertilizer application and mowing. This finding was confirmed in a subsequent controlled laboratory experiment using plants inoculated with land-use-specific microbiomes. Therefore, natural modulations of the plant microbiome may be the key to species persistence and ecosystem stability. A prerequisite for this microbiome-mediated tolerance is the availability of diverse local sources of microorganisms that can function as a resource for rapid modulations in response to change. Thus, conservation efforts must protect microbial diversity, which can help mitigate the effects of global change and facilitate environmental and human health.

ecology↗

Genetic variation in herbivore resistance within a strawberry crop wild relative (Fragaria vesca L.)

To decrease the dependency on chemical pesticides, the resistance of cultivated strawberry to pests needs to be increased. While genetic resources within domesticated varieties are limited, wild genotypes are predicted to show high heritable variation in useful resistance traits. We collected 86 wild accessions of Fragaria vesca L. from central Sweden and screened this germplasm for antibiosis (pest survival and performance) and antixenosis (pest preference) traits active against the strawberry leaf beetle (Galerucella tenella L.). First, extensive common garden experiments were used to study antibiosis traits in the sampled plant genotypes. Heritable genetic variation among plant genotypes was found for several antibiosis traits. Second, controlled cafeteria experiments were used to test for plant genetic variation in antixenosis traits. The leaf beetles avoided egg laying on plant genotypes possessing high antibiosis. This indicates a high degree of concordance between antibiosis and antixenosis, and that the beetles egg-laying behaviour optimizes the fitness of their offspring. The existence of high genetic variation in key resistance traits suggests that wild woodland strawberry contains untapped resources that are sought to reduce pesticide-dependence in cultivated strawberry. Given that only a very small portion of the species distribution area was sampled, even higher variation may be expected at the continental scale. As a whole, the genetic resources identified in this study serve to strengthen the position of woodland strawberry as a key crop wild relative.

plant biology↗