Programmi di miglioramento genetico finalizzati alla costituzione di nuove varietà di specie orto-floricole e ornamentali utilizzando metodi convenzionali di selezione assistiti da marcatori molecolari

PhD research activities focused on the application of molecular tools to help breeding for ornamental species. First of all, the state of art of modern breeding traits of interest and methodologies for ornamentals and other plant types particularly suitable for urban areas was reviewed. In fact, molecular techniques can contribute to variety development in several ways and the presented work include different research lines subdivided by specific breeding objectives. Modern recombination techniques can achieve new traits of interest and for this purpose Male Sterility (MS) and Gene Editing (GE) were considered. A review analyzing the new GE techniques for the goal achieving was preliminarily carried out. Then, a candidate gene for MS comparison in Petunia (Petunia × hybrida hort. ex E. Vilm) was identified and in vitro tests aimed at the obtainment of DNA-free edited lines through the CRISPR-Cas9 system were carried out. In addition, production of molecular profiles through DNA markers of commercial lines can guarantee Plant Variety Protection (PVP) and that of experimental lines can favour cross and selection management (Marker-Assisted Breeding - MAB). To this aim, a Genotyping By Sequencing (GBS) analysis was effectively performed on breeding clonal lines of the species Lantana (Lantana camara L). In the same experiment, the obtained molecular profiles allowed the correct prediction of the line ploidy level. Furthermore, GBS was also effectively used for the analysis of experimental clones of Petunia. The chosen approach also allowed to identify polymorphisms putatively involved in trait manifestation, in order to subject them to functional analyses, and to obtain the minimal marker Core Set able to provide the correct genotyping. In conclusion, through molecular techniques this study encourages the advancement of breeding for ornamental species in order to produce innovative varieties able to cope with climate change and future challenges.