The effect of in vitro culture conditions on the pattern of maximum photochemical efficiency of photosystem II during acclimatisation of Helleborus niger plantlets to ex vitro conditions

摘要: The influence of in vitro conditions including sucrose and nitrogen content the culture medium as well temperature on pattern chlorophyll a photochemical efficiency photosystem II (PSII) Helleborus niger L. plantlets upon transfer to ex were examined. In experiment, micro-shoots which proliferated rooted media with different levels (10, 20, 30, 40, 50, 60, 70, 80 g L−1) salts KNO3 NH4NO3 (both 25, 100 % according MS medium), (15 20 °C) used. multiplication axillary shoots performed modified supplemented cytokinins (2iP, BAP kinetin, each at concentration 1.0 mg L−1) GA3 (2.5 mg L−1) added together. For rooting shoots, was IBA 1 mg L−1 NAA 0.1 mg L−1 maximal PSII immediately removal microplants from ranged 0.24 0.81 depending treatment. High (above 50 g L−1) standard (100 %) or decreased 25 % 20 °C decrease transplanting time hinder acclimatisation further growth out culture. During conditions, gradual increase vitro-derived leaves observed all treatments. 0.79 0.83 after 4 weeks 20 weeks, indicating that H. gradually adapted greenhouse recovered their photosynthetic performance.