Strategy to improve the quality, the acclimatization and the ex vitro re-introduction of micropropagated plants of Limonium cordatum (L.) Mill., a Mediterranean endemism.

Limonium cordatum is a halophilous plant which lives in a very restricted area on the coast of the Mediterranean. It is included in the regional Red Lists of thretened plants in the Ligurian Regiona (I) and in the Dept. des Alpes Maritimes (F) (IUCN, 1998). In order to implement a successful conservation strategy, the possibility to establish a protocol of in vitro micropropagation was explored. Shoots regenerated from immature flower stens resulted to be the best sterting materials. Sterile shoots were cultured on an agar medium containing Murashige and Skoog medium (1962) salts and vitamins, 30 g/L sugar, supplemented with 6-BA 0.2 mg/L and IAA 0.5 mg/L. Under these conditions it was possible to obtain a highmultiplication rate but the shoots produced were not suitable for rooting and acclimatization. To improve the quality of the micropropagated plants, we investigated the effect of 2 different light intensities and two temperature levels. With the lowest light intensisty, it was possible to obtain rooted plants which could be sucessfully transferred to the greenhouse. Six-month old acclimatized plants were used in an in situ reintroduction programme.