bioRxiv Science⌕ Search

Biology subjects

Gaccione, L.

Publications and source records attributed to Gaccione, L..

2 recordsLinked to original sources

A first pangenomic framework for globe artichoke supports SNP-based varietal fingerprinting

Globe artichoke (Cynara cardunculus var. scolymus L.) comprises a broad range of local ecotypes and varietal groups whose genetic diversity has been investigated through different molecular markers. However, recent advances in next-generation sequencing and pangenomics approaches provide new opportunities to capture genome-wide variation at higher resolution and to develop practical tools for varietal discrimination, traceability, and germplasm conservation. In this study, we developed the first pangenomic framework for cultivated artichoke and evaluated pangenome-informed SNP markers for varietal fingerprinting. Whole-genome resequencing data from the Italian local ecotype Asti Sori were integrated with publicly available genomic data from representative globe artichoke and cultivated cardoon accessions to construct and annotate a pangenome. Genome-wide SNP and presence/absence variation (PAV) analyses were combined with pangenome-anchored genotyping-by-sequencing (GBS) data from 45 accessions representing the main cultivated varietal groups. The pangenome revealed a largely conserved core gene repertoire alongside a smaller accessory component, with gene accumulation curves suggesting a tendency toward saturation within the sampled cultivated germplasm. SNP- and PAV-based analyses provided complementary views of accession relationships and consistently resolved the principal cultivated groups. Across the broader germplasm panel, pangenome-anchored GBS-derived SNPs identified well-supported phylogenetic clusters corresponding to recognized varietal types. A reduced panel of 50 SNPs, selected through iterative random subsampling, retained at least 90% of the genetic diversity captured by the full dataset and reproduced its main population structure. This compact pangenome-anchored marker set provides a practical foundation for varietal fingerprinting, DUS-oriented applications, traceability, and conservation of traditional globe artichoke germplasm. Validation across independent collections will be required before routine deployment.

Plant Biology↗

Association analyses reveal both anthropic and environmental selective events during eggplant domestication

Eggplant (Solanum melongena) is one of the four most important Solanaceous crops, widely cultivated and consumed in Asia, the Mediterranean basin, and Southeast Europe. We studied the Genome-wide association (GWA) of historical genebank phenotypic data on a genotyped worldwide collection of 3,449 eggplant accessions. Overall, 334 significant associations for key agronomic traits were detected. Significant correlations were obtained between different types of phenotypic data, some of which were not obvious, such as between fruit size/yield and fruit color components, suggesting simultaneous anthropic selection for genetically unrelated traits. Anthropic selection of traits like leaf prickles, fruit color, and yield, acted on distinct genomic regions in the two domestication centers (India and Southeast Asia), further confirming the multiple domestication of eggplant. To discriminate anthropic from environmental selection in domestication centers, we conducted a Genotype-Environment Association (GEA) on a subset of georeferenced accessions from the Indian subcontinent. The population structure in this area revealed four genetic clusters, corresponding to a latitudinal gradient, and environmental factors explained 31% of the population structure when the effect of spatial distances was removed. GEA and outlier association (OA) identified 305 candidate regions under environmental selection, containing genes for abiotic stress responses, plant development, and flowering transition. Finally, in the Indian domestication center anthropic and environmental selection acted largely independently, and on different genomic regions. These data allow a better understanding of the different effects of environmental and anthropic selection during domestication of a crop, and the different world regions where some traits were initially selected by humans.

genomics↗