Title : Biotechnologies for ex situ Conservation of botanical important Plant Species and molecular Techniques used for investigating in vitro genetic Stability.
Abstract:
Nowadays, ex situ biodiversity conservation is a very important complementary approach of in situ conservation. Ex situ preservation is based on (i) classical methods (field collection, Botanical Gardens, Arboreta, Seeds banks) and on (ii) modern methods using biotechnologies (in vitro tissue culture and collection, medium and long-term preservation, artificial seeds, etc.). The Global Strategy for Biodiversity Conservation (2011-2020) claims that “at least 75 % of threatened plant species to be preserved in ex situ collections, preferably in the country of origin, and at least 20 per cent to be available for recovery and restoration programs”( target 8). In Romania, 14.5% of the vascular plant taxa are threatened (Dihoru and Negrean, 2009). The ex situ important botanically taxa conserved by our team are: Lychnis nivalis, Moehringia jankae, Silene dinarica, Dianthus callizonus, D. giganteus subsp. banaticus, D. glacialis subsp. gelidus, D. henteri, D. nardiformis, D. pratensis subsp. racovitzae, D. spiculifolius, D. trifasciculatus subsp. parviflorus and D. tenuifolius. These taxa were sampled from their natural habitats. All these taxa were successfully introduced in vitro and there are maintained during 3 to 9 years in ex situ collections. The in vitro experiments aimed to obtain an optimum multiplication and rhizogenesis rate. The rooted or unrooted vitroplants were ex situ acclimatized – in laboratory, in greenhouse and then outdoor, on a rocky area in the Botanical Garden.
Molecular analyses of the plant material to assess the somaclonal variability were carried out in more stages: at the moment of sampling, after in vitro preservation with or without slow growth, after cryopreservation. As methods for the evaluation of the modern preservation technologies we used molecular markers as SSR and ISSR. Molecular markers revealed genetic stability of preserved plants. In vitro culture induced several low differences between plants, thus ISSR markers are more valuable for analysis of the genetic stability of preserved plant. SSR markers are not so polymorphic in comparison with ISSR markers, thus SSR patterns were the same in plants preserved by different methods. SSR markers are valuable tools for analysis of genetic structure of the populations.
