Valsorda, Gualdo Tadino - Viola eugeniae Parl.
R. Gasparri1, S. Casavecchia1, M. Galié1, S. Pesaresi1, P. Soriano2, E. Estrelles2, E. Biondi1
1Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, 60131 Ancona, Italy.
2ICBiBE-Jardí Botànic, University of Valencia, Calle Quart 80, 46008 Valencia, Spain.
Salicornia patula Duval-Jouve is a diploid species that usually shows a small bushy growth form. It is an important component of the halophytic annual pioneer vegetation of salt marshes. This hyper-saline vegetation is rare and threatened by a wide variety of pressures (tourist and industrial practices, coast management, invasive species) in the European Mediterranean area. S. patula is a characteristic species in the habitat 1310 "Salicornia and other annuals colonizing mud and sand". This paper shows an analysis (by GLM and PCA) on the germination response to temperature and salinity of three populations of S. patula from different localities (Italy, Spain and Croatia) in order to identify the key factors controlling germination phases for the implementation of projects on conservation and environmental restoration of the hypersaline environments. We assessed the interspecific competitiveness of species related to several localities. The germination of S. patula was mainly influenced by temperature and salinity and secondly by the site of collection of seeds. In fact, even though S. patula optimal temperature range was between 25 and 35° C, the pattern of the germination response curve shows three distinct levels induced by the site of collection of seeds. For salinity, S. patula showed the ability to germinate at high salinities even in this case with distinct levels induced by the site of collection of seeds. This might suggest an adaptation of S. patula to the different sites bioclimatic conditions here estimated by summer and annual aridity. The population of Sentina Natural Regional Reserve had higher percentages of germination under saline conditions than the other populations. The seeds of the population from Blace were less salt tolerant than those of the populations from Sentina and Girona in the recovery responses. In conclusion, the local environmental conditions, especially Io and Ios2, are important variables to characterize and diversify the seed germination behavior in the three populations. In addition, S. patula seeds are able to germinate in high percentages in a rather wide range of temperature and salt concentration. Thus, it can be stated that the S. patula populations studied can be easily multiplied and successfully used for projects on conservation and environmental restoration of hypersaline environments.
Croatia, habitat restoration, hyper-saline vegetation, Italy, Salicornia patula, seed germination, Spain.