SUMMARY
Nowadays, the plant biodiversity is threatened and its conservation represents a priority at the international level. Conservation strategies are based on the management of wild populations in nature, but they require additional methods of ex situ conservation which helps preserve plants. The experiments in this article focused on testing the in vitro reactivity and adventitious rooting of three rare species of Dianthus from Romania (Dianthus giganteus banaticus, Dianthus spiculifolius and Dianthus henteri), which are part of the Red List of Romania’s Flora. The in vitro cultures were initiated from stem fragments and seeds belonging to the Dianthus species, which were sterilized using different sterilizing agents. Seeds were cultivated on a simple MS with IBA and BAP. In the present study, five different culture media, supplemented with auxin and cytokinin, were tested for the explants, to observe the in vitro behavior of Dianthus species in terms of proliferation and rooting. The contamination and germination rates were determinated. The best germination rate was achieved by D. giganteus banaticus. The number of shoots and roots, the length of shoots, initiated for explants varied according to the concentration of growth regulator in the medium. The plants had a good in vitro behavior, but the adventitious rooting was weak, which represents a limiting factor in the acclimatization of plants. Plant micropropagation and conservation may also contribute to maintain natural populations through reintroducing the preserved material in the original habitat