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Garcia-Fernandez, A.

Publications and source records attributed to Garcia-Fernandez, A..

4 recordsLinked to original sources

In situ evaluation of artificial selection and assisted gene flow for the advancement of flowering onset in Lupinus angustifolius L. (Fabaceae)

Artificial selection and assisted gene flow represent promising conservation strategies for enhancing species adaptive capacity under accelerating climate change. We tested the application of artificial selection and assisted gene flow by evaluating progeny performance under field conditions, using Lupinus angustifolius L. (Fabaceae) as a model to advance flowering onset. Seeds were collected from four wild populations and two contrasting latitudes in Spain for parallel artificial selection and assisted gene flow three-year experiments. In the artificial selection treatment, we developed two early-flowering selection lines per population over three generations using both selfing and outcrossing. For assisted gene flow, we created F1 hybrids by crossing northern populations with southern pollen donors, then produced F2 and F3 generations through successive self-pollination. Finally, F3 seeds from this process were sown in autumn in a common garden under natural conditions, near the original population sites. Spring 2021 measurements of flowering onset and morphological traits revealed contrasting treatment effects. Artificial selection lines showed no significant phenotypic differentiation from controls across all measured traits, contradicting previous controlled-environment results. Conversely, assisted gene flow lines exhibited significantly earlier flowering and reduced shoot growth relative to controls, consistent with prior findings under controlled conditions. These results show greater efficacy of assisted gene flow over artificial selection for advancing flowering onset under natural conditions.

evolutionary biology↗

Rapid adaptation and extinction across climates in synchronized outdoor evolution experiments of Arabidopsis thaliana

Climate change is threatening species with extinction, and rapid evolutionary adaptation may be their only option for population rescue over short ecological timescales. However, direct observations of rapid genetic adaptation and population dynamics across climates are rare across species. To fill this gap, we conducted a replicated, globally synchronized evolution experiment with the plant Arabidopsis thaliana for 5 years in over 30 outdoor experimental gardens with distinct climates across Europe, the Levant, and North America. We performed whole-genome sequencing on [~]70,000 surviving reproductive individuals and directly observed rapid and repeatable adaptation across climates. Allele frequency changes over time were parallel in experimental evolution replicates within the same climates, while they diverged across contrasting climates--with some allele frequency shifts best explained by strong selection between -46% to +60%. Screening the genome for signals of rapid climate adaptation identified a polygenic architecture with both known and novel adaptive genetic variants connected to important ecological phenotypes including environmental stress responses, CAM5 and HEAT SHOCK FACTORs, and germination and spring flowering timing, CYTOCHROME P450s and TSF. We found evolutionary adaptation trends were often predictable, but variable across environments. In warm climates, high evolutionary predictability was associated with population survival up to 5 years, while erratic trends were an early warning for population extinction. Together, these results show rapid climate adaptation may be possible, but understanding its limits across species will be key for biodiversity forecasting.

evolutionary biology↗

ERGA-BGE genome of Cheirolophus tagananensis: an IUCN endangered shrub endemic to the Canary Islands

The reference genome of Cheirolophus tagananensis, locally known as the Cabezon de Taganana, will provide an exceptional opportunity to establish a new framework to develop comparative genomic tools. These tools will help uncover the genetic basis of rapid plant radiations and microevolutionary adaptation processes of insular species on oceanic islands. This genomic resource will also contribute to facilitate the establishment of better informed in situ and ex-situ conservation strategies for this narrow endemic in the face of potential habitat degradation, and support taxonomic studies to better understand genetic diversity at the population, species, and genus levels. A total of 16 contiguous chromosomal pseudomolecules were assembled from the genome sequence. This chromosome-level assembly encompasses 0.62 Gb, composed of 421 contigs and 235 scaffolds, with contig and scaffold N50 values of 4.0 Mb and 36.5 Mb, respectively.

genomics↗

Effects of assisted gene flow on the flowering onset of the annual legume Lupinus angustifolius L.: from phenotype to genotype.

Current climate change may impede species to evolutionary adapt quickly enough to environmental changes, threatening their survival. In keystone populations, it may be necessary to consider the introduction of adaptive alleles through assisted gene flow. Considering that flowering time is a crucial trait in plant response to global warming, the objective of our study was to test the potential benefits and limitations of assisted gene flow for enhancing the evolutionary potential of Lupinus angustifolius L. (Fabaceae) populations through the advancement of flowering time in the context of global warming. Previous studies have shown that southern populations of L. angustifolius flower earlier than northern populations. We collected seeds from four populations in Spain from two different latitudes, and we established them in a common garden environment. To advance the flowering onset of northern populations, we used pollen from southern individuals to pollinate plants from northern populations, creating an F1 gene flow line. In the following season, the F1 gene flow line was self-pollinated to create an F2 self-pollination line. In parallel, individuals from the F1 gene flow line were pollinated again with pollen from northern plants, thus creating a backcross line. We also included a control line resulting from a random selection of individuals in each population in the first generation and their descendants from self-crosses in the second generation. We measured flowering onset, reproductive success and other plant traits in all individuals resulting from these lines. To characterize the effects of the assisted gene flow line at the genomic level, we carried out a gene capture analysis to sequence genes related to reproduction, growth, stress, nitrogen, and alkaloids in individuals from the F1 gene flow line and the control line in the first generation. All gene flow-derived lines flowered significantly earlier than the control line. Furthermore, plants from the F1 gene flow line produced heavier seeds and had a lower shoot growth than the control line. Genomic analyses identified 36 SNPs outliers that were associated to flowering onset, seed weight, and shoot growth. These results highlight that assisted gene flow can increase the evolutionary potential of populations by modifying the values of a specific trait. However, the modification of one trait may affect the values of other plant traits. The characteristics of the populations will have a fundamental effect on the results of assisted gene flow. Therefore, the selection of the donor population is a critical step in this process.

evolutionary biology↗