The objective of this work was to evaluate the effect of pulse on in vitro multiplication of Eucalyptus grandis. Interactions were evaluated among BAP concentrations (0, 200, 400 and 600 mg L-1), exposure time (1, 2 and 3 hours), pH values (3 and 5.8), and explant morphological changes. Fresh weight of the explants was determined weekly. At 21 days of culture, valuations were made of the number of shootings per treatment, number of shootings obtained per explant (multiplication rate), and seedlings rescue was accomplished for histological analysis. The pH values did not present any interaction with the other factors. The most significant treatments on E. grandis shoot multiplications were 200 mg L-1 of 6-BAP during 1 and 2 hours. There was an intensification of cell division in the cortical parenchyma and procambium, represented by the arising of meristems in response to 200 mg L-1 of BAP treatment, during 1 and 2 hours. The use of the pulse on in vitro multiplication of E. grandis is feasible.
micropropagation; forest essence; histology; plant growth regulator
