Aiming to minimize the costs of in vitro conventional multiplication of blueberry (Vaccinium ashei Reade) and to optimize the production of micropropagated seedlings of this particular species, this work compared the effect between natural and artificial light by cultivating the explants in different growth places (greenhouse and growth room). Also, it was tested two seasons: summer and winter, as well as the effect of different sucrose concentrations added to the culture environment and different types of flasks sealing. During the 60 days of in vitro multiplication, it was assessed the average shoot number, multiplication rate and total fresh matter. It was verified that the use of different materials for sealing does not alter the shoot length; however, it promotes different performances on multiplication rate, on the average leaves number and mainly on the amount of total fresh matter. Explants grown in flasks closed with plastic film or aluminum increase the number of leaves and the multiplication rate. On the other hand, explants grown in flasks closed with cotton and under photoautotrophic conditions increase in great scale the amount of total fresh matter. Under conventional conditions of micropropagation the addition of 15 g.L-1 sucrose to the culture environment favors the increase of leaves number, the multiplication rate, the total fresh matter and the shoot development. Nevertheless, for most of the variables the addition did not differ significantly from the cultivation in sucrose absence. The explants growth, under different growth places and year time, showed different performances regarding to the analyzed variable.
Vaccinium ashei; flasks closure; greenhouse; sucrose
