TOWARDS A BETTER UNDERSTANDING OF THE ECOLOGY AND BIOLOGY OF THE SUBENDEMIC IONOPSIDIUM SAVIANUM (CARUEL) ARCANG. IN CENTRAL ITALY

Jonopsidium savianum (Caruel) Ball ex Arcang. is an annual subendemic species, whose fragmented distribution area is limited to N-Spain (Burgos and La Rioja) and central Italy (Umbria, Latium and Tuscany) (1). It is included in the Annexes II and IV of the "Habitats" Directive (92/43/EEC and subsequent amendments). The species has been assessed as "Least Concern" in the recent Italian Red List (2), while at the EU level it is considered "Near Threatened" (3). Considering the biogeographic relevance of this very localized species, in 2010 and 2016 we carried out a study of its central-Apenninic populations, from Umbria (M. Torre Maggiore, Colle delle Centelle) and Latium (M. Tancia). Demographic, morphologic, ecological and reproductive traits of J. savianum have been measured. Among the considered parameters are the genet's density, size, habitus (single or multiple stems), number and size of flowers and fruits. We investigated the reproductive biology of the species, focusing on size, weight and morphology of seeds, germinability tests at different thermal regimes with several thermal stratification protocols, rate and speed of germination. The density parameters were measured within 40x40 cm2 squares, located at intervals of 1 m along transects crossing the local stands. The macromorphological parameters were measured on eight randomly chosen individuals from each of eight transects randomly located in each of the three study site. Data and methods match with the methodological protocols officially acknowledged for evaluating the conservation status of this species (4). Correlation with ecological characteristics has been investigated, with focus on soil texture, light availability and climatic parameters. Nuclear (ITS and ITS2) and plastidial (matK, rbcL, trnH-psbA) DNA multi-marker barcodes were amplified, adding relevant information to the general knowledge of a taxon of community interest, for which only karyological data were available (5). The statistical analysis of data was performed using the software “R” (https://www.r-project.org/, 2016), in order to assess the variability and to point out any significant different distribution among the considered traits, in relation to the considered environmental characteristics. The results obtained from this study contribute to a better understanding of the ecology and biology of J. savianum in central Italy and will support the periodical monitoring that Regional authorities are obliged to perform every six years, the next being expected for the end of the period 2013-2018. Jonopsidium savianum is a species whose conservation is strongly depending on the maintenance of traditional extensive montane farming. The present study provides useful insights for a proper planning for the preservation of viable populations of this species. It should be stressed that currently only two of the studied local populations are included in the network of Natura 2000 areas.