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In order to examine the factors affecting the normal growth and survival of plantlets of wild cherry (Prunus avium L.) after transferring from in vitro conditions into soil, an anatomical and physiological study was carried out on leaf, stomata in three conditions, in vitro and ex vitro, after 2 and 4 weeks. The anatomical observation, showed no significant differences between stomata of in vitro and ex vitro plantlets in shape, size and frequency. Stomata of in vitro showed.Malfunctioning in response to light, CO2 concentrations and water deficit comparing to those transferred and acclimatized in soil after 4 weeks. The concentrations of K+, Na+ and Ca2+ in leaves of in vitro plantlets indicated that these, ions could involve in this malfunctioning. The presence of high concentration of nitrogen and sodium in leaves of in vitro cultured of wild cherry could also inactivate ABA, resulting in lack of stomata responses to environmental stresses.

The present study was conducted to ascertain the ability of Dracaena sanderiana ‘ Victory’ , a foliage plant species of commercial importance in both domestic and international markets, to thrive under contrasting light environments. The experiment was carried out inside a semi-open greenhouse in Peradeniya, Sri Lanka. Same-sized and same-aged, ready-to-ship export quality plugs of Dracaena sanderiana ‘ Victory’ were grown in plastic pots filled with the standard medium for foliage plants recommended by the Department of Agriculture. The plants were exposed to four different light treatments: Full sunlight, 15% shade under a green net, and 50% and 80% shade under a black net. Morphological and growth-related parameters were measured, and an aesthetic evaluation was done to verify the overall conformity of plants until 100 days after planting with every 20-day intervals. ‘ Victory’ showed variable responses to different light conditions where leaf-related parameters were significantly altered, while the relative growth rate was kept uniform across light environments. Weight ratios that reflect the dry matter partitioning were unchanged. Most of the responses under the black net (50% shade) were comparable to those under the green net (15% shade), where the R: FR ratio was reduced. It was found that the plants could easily be acclimatized to the light conditions used in the present study. Interestingly, this cultivar scored more than 80% in the aesthetic evaluation for any given light condition, which indicates the potential of using this cultivar in heterogeneous light environments while keeping the aesthetic appearance unaltered.

Optimizing the tissue culture condition for Adenium sp as an imported ornamental plant with a low propagation rate can deliver the way for mass propagation to multiplication of this ornamental plant. So, this research was carried out in a factorial experiment based on a completely randomized design to optimize organogenesis of Adenium abessum and Adenium arabicum during shoot induction, proliferation and root induction experiments. The highest rate of shoot regeneration for Adenium obesum was achieved in MS medium containing 0. 5 mgl-1 BA, and for Adenium arabicum was achieved in MS medium containing 0. 5 mgl-1 BA in combination with 0. 5 mgl-1 TDZ. Organogenesis was more observed as leafy and rooted in A. arabicum and shoot induction in that was longer compare with A. abessum. The result showed that 0. 5 mgl-1 BA can be used to prolifered shoots induced in both specie of Adenium. The full strength of free plant growth regulator MS medium supplemented with 0. 3% activated charcoal was the best treatment at root induction stage. The plantlet gradually became first adapted in sterile perlite with 1/2 MS concentration and then in the culture media contained soil, vermicompost and perlite.