ESPLORANDO LE DINAMICHE DEL SISTEMA DI AUTO-INCOMPATIBILITÀ NELLA CICORIA E IL SUO IMPATTO SULLA GENETICA DI POPOLAZIONE E SUL MIGLIORAMENTO GENETICO

This thesis explores the genetic architecture of the genus Cichorium through five interrelated chapters, focusing on morphological, phylogenetic, cytological, histological, and molecular aspects, with a special emphasis on the self-incompatibility (SI) system in Cichorium intybus, the genus's most agriculturally and economically significant species. Chapter I introduces Cichorium, detailing its genetic diversity, and utilizes ddRADseq to construct a phylogenetic tree across multiple varieties and species, identifying genomic regions relevant for marker-assisted breeding and product traceability. Chapter II reviews linkage mapping and marker-assisted breeding for C. intybus, producing consensus maps to standardize molecular data and support breeding programs aimed at improving agronomic traits. In Chapter III, reproductive biology is examined, particularly SI in C. intybus, using Confocal Laser Scanning Microscopy to analyze embryo sac development and pollen-stigma interactions, providing insights into SI mechanisms. Chapters IV and V shift focus to molecular characterization of SI, mapping the S-locus to chromosome 5 and identifying ciMIK2 as a candidate gene linked to SI. Detailed analyses of gene expression and RNA-seq data reveal transcriptional changes associated with SI, offering new insights into the underlying molecular mechanisms. This research enhances our understanding of the SI system, contributing to both evolutionary biology and applied plant breeding, and lays the groundwork for future investigations into SI's complexity and diversity within Cichorium and the broader Asteraceae family.