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

Abstract

Since the 19th century, the cultivation of Ocimum basilicum L. has increasingly been established in Liguria, with the 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 to characterize these CVs by morphological and phytochemical analyses to safeguard their biodiversity. Commercial O. basilicum Genovese Superbo grown in Liguria (SL) was added for comparison. The micro-morphological investigation showed significantly different trichome densities among the samples. CV4 showed the highest densities of both peltate and capitate trichomes, while CV9 and CV1 had the lowest peltate and capitate densities, respectively. In addition, to perform the germplasm characterization, seed morphometric data and germinability were evaluated. Volatile Organic Compounds (VOCs) analysis was carried out on CV1–9, SL, and Superbo plants grown in Piedmont (SP), to test the influence of territory on basil aromatic profiles. The results showed that the old accessions and SL were rich in linalool, eugenol, and bergamotene. Only CV1 slightly differed, with higher levels of methyl eugenol, eucalyptol, and camphor. On the contrary, SP had very high levels of methyl eugenol and camphor. These data represent valuable insights for preserving Ligurian old basil accessions and maintaining the production of Genovese Basil PDO (Protected Designation of Origin) in the future.

Keywords

• <i>Ocimum basilicum</i>
• Liguria
• agrobiodiversity
• germplasm conservation
• glandular trichomes
• VOCs