GENOMICS FOR WILD AND MEDICINAL PLANT DIVERSITY STUDIES

Genomic resources are a fundamental asset in investigating genetic diversity, evolutionary history and adaptive potential of populations. During this doctorate, we aimed at developing genomic resources for non-model, medicinal plant species in order to facilitate research in biodiversity genomics, flower development, and genetic improvement, focusing on two plant species: Salvia pratensis and Althaea officinalis. In one part of the project, a good quality, annotated genome assembly was obtained for Salvia pratensis. The genome was used to study flower development related genes of the MADS-box family of transcription factors and as a reference to perform species delimitation between S. pratensis and three closely related taxa which are endemic to Italy or have an otherwise restricted range. A phylogeny for Italian Salvia species was also obtained. Genetic variation data was obtained with Genotyping-By-Sequencing (GBS). In the second part of the project, in collaboration with Aboca S.p.A. Società Agricola, we set the basis for future studies aimed at improving Aboca’s collection of Althaea officinalis, a medicinal plant used for many natural products, to increase activity of its root extracts. Experimental fields were set up in Aboca and Milan to obtain plants for genome size estimation and to test the viability of self-pollinated seeds. Finally, a protocol was set up in Aboca to efficiently obtain root extracts from individual plants, in order to have a measure of the desired phenotype. This is essential to verify how much variation is present in the collection and in the future link it to the plant’s genotype. The results from this project set the stage for improving the ex situ collection of the Salvia genus in the Botanical Garden of Brera, give support to delimitation of endemic Italian species, and set the stage for genetic improvement of Aboca’s collection, potentially with integration of wild genotypes.