Molecular Characterization of Natural Populations of Glycyrrhiza glabra L. (Fabaceae) in the Provinces of Agrigento and Trapani (Sicily, Italy, Europe)

Glycyrrhiza glabra is an herbaceous plant native to Eurasia, living in mild climates, and spread worldwide. Liquorice serves as a vital resource for human health, used as medicinal plants in feed and food, with anti-inflammatory and anticancer properties. To the best of our knowledge, no genetic studies on Italian populations of this species have been reported so far. This study investigated for the first time the genetics of the Mediterranean G. glabra samples found in small natural meadows in Agrigento and Trapani provinces (Sicily, Italy). To assess possible genetic differences among samples, two molecular markers were employed, ribosomal DNA-Internal Transcribed Spacer (rDNA-ITS) regions and Inter-Simple Sequence Repeats (ISSRs), both widely used for evaluating intra- and interspecific variability. Partial sequencing of the rDNA-ITS region was performed on five samples collected from two distinct locations in Agrigento and Trapani provinces, revealing complete sequence identity among them. ISSR analysis further confirmed the genetic conservation of samples. We also compared, by multiple alignment and phylogenetic analysis, the Sicilian rDNA/ITS sequences with G. glabra sequences coming from other countries, and with other species of Glycyrrhiza such as G. uralensis, G. inflata, G. aspera, G. echinata, and G. pallidiflora. The results revealed a high similarity among all analyzed sequences. Studying the genetic diversity of liquorice is important in preserving its medicinal properties, supporting plant conservation programs, and in expanding its applications in the healthcare field.