The great interest for heliconias by the external market has placed this crop in a prominent position in the flower production chain. The small offer of healthy seedlings, however, the expansion of this activity. The presence of endophytic microorganisms such as Pseudomonas sp. represents an obstacle even for the evolution of heliconia tissue culture studies. Stem apices of Heliconia rauliniana were inoculated and analyzed in vitro to investigate the presence of endophytic microorganisms. An antibiotic analysis was also run for posterior microbiological control. The presence of Pseudomonas sp. and Klebsiella sp. in stem apices confirmed infection. Antibiotics such as chloramphenicol, cefotaxime and the association of both (chloramphenicol + cefotaxime) at rates of 50, 150, 250 and 500 mg L-1, were applied to the MS medium and supplemented with 3.5 mg L-1of 6-BA. After a 50 day-period, 500 mg L-1 of cefotaxime was the most efficient form to control endophytic microorganisms in this species of heliconia. The chloramphenicol, although effective for endophytic microorganism control, was inadequate for in vitro growth due to its cytotoxicity to explants.
tissue culture; microbiologic control; endophytics