Morphological and Phytochemical Characterization of Old Ligurian Basil Accessions: Recovery of Old Biodiversity for Future Exploitation

Since the 19th century, cultivation of Ocimum basilicum L. has increasingly been established in Liguria, with in situ reproduction of seeds. Over the years, Ligurian basil accessions were crossed with allochthonous genomes to obtain disease-resistant plants. To preserve the original genetic resource, nine old Ligurian accessions (CV1-9) were recovered. As part of the PSR 2014-2022 Mis. 10.2 of Liguria Region, this work aimed at characterizing these CVs by morphological and phytochemical analyses to safeguard their biodiversity. Commercial O. basilicum Genovese Superbo grown in Liguria (SL) was added for comparison. Micro-morphological investigation showed a significantly different trichomes density among the samples. CV4 showed the highest density of both peltate and capitate trichomes, while CV9 and CV1 had the lowest one of peltate and capitate, respectively. VOCs analysis was performed on CV1-9, SL and on a plant of Superbo grown in Piedmont (SP), to test the influence of the territory on basil aromatic profile. Indeed, the old accessions and SL were rich in linalool, eugenol, and bergamotene. Only CV1 slightly differed for higher levels of methyl eugenol, eucalyptol, and camphor. On the contrary, SP had very high levels of methyl eugenol and camphor. This data represents valuable insights for preserving Ligurian old basil accessions and maintaining Genovese Basil PDO production in the future.