Rare and endemic plant species of Mountain Crimea flora: a morphogenic response to conservation in the gene bank in vitro

Biotechnological approaches have been actively used in recent years to preserve rare and endemic plant species under slow growth conditions. This is reached by lowering the temperature and light intensity, increasing the osmotic concentration, introducing retardants into the culture medium. For conservation, we used microshoot segments of Lamium glaberrimum (K. Koch) Taliev (Lamiaceae), Crepis purpurea L. (Asteraceae), Scrophularia exilis Popl. (Scrophulariaceae), Silene jailensis N. I. Rubtzov (Caryophyllaceae) cultured under standard in vitro conditions for 8‒10 months. The explants were placed on ¼ MS culture medium supplemented with plant growth inhibitors: 0.2 g/L 2-chloroethyl-trimethyl-ammonium chloride (CCC) and 60 g/L sucrose. Conservation conditions were: the temperature 4–6 °C, light intensity 1.25–3.75 µM m-2 s-1, photoperiod 16 hours. Screening of the morphometric parameters indicated high viability and a decrease in growth kinetics after 12 and 24 months of deposition in the gene bank in vitro. Along with the microshoot slow growth, the formation of adventitious shoots, leaves, and roots was observed.