| Resumo: |
Estimulation of autotrophy in in vitro plantlets could be achieved through changes in the culture medium, or by changing the traditional hermetic caps by one that could allow gas exchanges between the culture and the environment. Besides that, the use of lamps with distinct emission spectrum irradiaction has propitiated successful results. This work was carried out aiming to evaluate the either the combined or the single action of some factors that can induce autotrophy on in vitro A. andraeanum cv. Eidibel plantlets. 3 sucrose concentrations were used: 0, 15 and 60 mM and for each one, to kinds of flasks according to the cap ventilation: under (0.038 L.h-1) and without ventilation. Flasks were kept under cold light fluorescent lamps or under gro-lux lamps. At the end of the experiment showing the highest shoot dry mass treatment was 60 mM, under ventilation and gro-lux, and the treatment which accumulate root dry mass to a lesser extent were 0 mM with ventilation and cold light and 15 mM without ventilation and cold light. In average, treatments with higher sucrose content in the culture medium, that is, 60 mM, under gro-lux lamps, presented the highest chlorophyll a, b and total contents, than those under cold lamp. Steps of carbohydrates metabolism could be associated with the total soluble sugars (sucrose and reducing sugars) levels, highlighting the steps where nutrient requirements were higher, showing the role of the plantlets sink.
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