6-BENZYLAMINOPURINE AND ACTIVATED CHARCOAL AFFECT In vitro SHOOT MORPHOGENESIS OF Berberis buxifolia LAM

An important factor affecting the micropropagation is the quality and rate of shoot multiplication. The objectives of this work are to study the effect of concentration and BA continuous presence, and the addition of activated charcoal during two periods of culture on Berberis buxifolia morphogenesis processes during in vitro shoot multiplication. The addition of BA in the three subcultures favored the multiplication index compared with a pulse of BA in the first subculture, specially for 0.55 and 1.10 u M BA. LowerZM concentrations (0.55 to 1.10 /xM) were more favorable for shoot multiplication than 2.22 u M BA, allowing to obtain the highest multiplication index. The percentage of shoots longer than 5 mm was maximum with activated charcoal while the multiplication index were significantly lower than those obtained without activated charcoal. In the first culture period, the multiplication index were higher than in the second culture period. However, the percentage of shoots longer than 5 mm was significantly higher in the second culture period than in the first culture. The results obtained in this work show that the morphological processes observed during in vitro shoot multiplication of B. buxifolia can be controlled by the concentration and continuous presence of BA and the addition of activated charcoal.