Molecular and cytogenetic analyses in Geranium macrorrhizum L. wild Italian plants

Geranium macrorrhizum L. is a herbaceous species native to southern Europe and was introduced in central Europe and North America. It is also widely distributed in Italy. In this study, molecular and cytogenetic analyses were carried out on 22 wild plants, collected in central and southern Italy, compared with five cultivated plants, with the main purpose to identify those living near the Marmore waterfalls in central Italy, recently described as the new species Geranium lucarinii. Four barcoding markers (rbcL, matK, trnH-psbA intergenic spacer and internal transcribed spacer region) were sequenced and their variability among the plants was evaluated. Chromosome numbers were determined and 45S rDNA was physically mapped by fluorescence in situ hybridization. Moreover, genomic affinity between wild and cultivated plants was evaluated by genomic in situ hybridization. The results of this study supported that all the plants belong to G. macrorrhizum, including the Marmore population. Barcoding analyses showed a close similarity among the wild plants, and a differentiation, although not significant, between the wild plants on one hand and the cultivated plants on the other. Integrated studies focusing on morphological, genetic and ecological characterization of a larger number of wild populations would allow us to know the extent of the variability within the species.