Lina Podda

Assessing the potential invasiveness of Cortaderia selloana in Sardinian wetlands through seed germination study

Abstract The present work is focused on the study of abiotic factors that may favour seed germination and the potential invasiveness of Cortaderia selloana, with particular attention to wetlands. Germination tests were conducted at the Sardinian Germplasm Bank (BG‐SAR), testing different temperatures and percentages of NaCl in order to determine the optimal ecological conditions at which germination occurs and the effect of salt on seed germination and viability, as well as on seedling development. Seeds completely germinated at every temperature tested, but the highest germination rate was found at 25°C. Salinity did not prevent seeds from germinating, but it affected germination rate and seedling vigour.

What does the germination ecophysiology of the invasive Acacia saligna (Labill.) Wendl. (Fabaceae) teach us for its management

Acacia saligna is a phanerophyte native to Australia; it was introduced in the 1950s in Sardinia (Italy) for afforestation mainly in coastal areas and at present it is considered naturalized, becoming invasive in sand dune habitats. Seed biology is one of the most important factors contributing to the invasion success of Australian acacias, for this reason the germination ability is an important issue when trying to clarify the invasion dynamics of A. saligna. Germination tests were conducted at the BG-SAR, testing the effect of different temperatures and percentages of NaCl, on seeds belonging to five accessions from four populations of two coastal habitat types. The optimal temperature range for seed germination was 15–20°C; the increase of salt caused a decrease in the final germination percentages. At 1% of NaCl concentration, germination fell at 25–30°C and at 2% it was relatively low (below 40%) and occurred almost only at 15°C. This work represents a contribution to the knowledge of the seed ecology and germination behaviour of the species, providing new data on the interpopulation and interannual variability, and relating them to the invasion dynamics of A. saligna in the coastal Mediterranean habitats.

Territory defence throughout conservation of the plant diversity: the project of the Protected Sea Area of Capo Carbonara (South eastern Sardinia)

Contents, activities in progress and results achieved of a project on the conservation of the plant diversity of the Protected Sea Area of Capo Carbonara, funded in 2005 by the Ministry of Environment and Territory Protection are illustrated.

Checklist of gypsophilous vascular flora in Italy

Abstract Our understanding of the richness and uniqueness of the flora growing on gypsum substrates in Italy has grown significantly since the 19th century and, even today, new plant species are still being discovered. However, the plants and plant communities, growing on gypsum substrates in Italy, are still a relatively unknown subject. The main aim of this paper was to elaborate a checklist of the Italian gypsophilous flora, to increase knowledge about this peculiar flora and for which conservation efforts need to be addressed. Through a structured group communication process of experts (application of the Delphi technique), a remarkable number of experienced Italian botanists have joined together to select focal plant species linked to gypsum substrates. From the results obtained, 31 plant species behave as absolute or preferent taxa (gypsophytes and gypsoclines) and form the ‘core’ Italian gypsophilous flora. The most abundant life forms were chamaephytes and hemicryptophytes, belonging to Poaceae and Brassicaceae; as for chorotypes, the most represented are Mediterranean and narrow endemics. By improving on previously available information about the flora with a clear preference for gypsum in Italy, this undertaking represents an important contribution to the knowledge of a habitat which is today considered a priority for conservation.