The objective of this work was to evaluate the effects of antibiotics on the in vitro growth and multiplication rate of potato. Potato explants, cv. Baronesa, were cultivated in semi-solid and liquid multiplication culture medium. The medium was formed by MS salts, vitamins and one of the following antibiotics: ampicillin, chloramphenicol, streptomycin or tetracycline, previously selected by the bactericidal action on some culture contaminants, at 0, 32, 64, 128, 256, 512 and 1,024 mg L-1. Each treatment had three replicates of ten explants. The materials were incubated for 21 days in a growth room at 25±2°C temperature, 16-hour-light and 35 µmol m-2 s-1 radiation. The flasks with liquid culture medium were kept under continuous agitation in an orbital shaker. Only ampicillin has not affected the survival and the normal development of potato explants in the culture medium, thereby being indicated for decontamination works in vitro of this specie. The increase of the concentrations of chloramphenicol, tetracycline and streptomycin presented severe phytotoxic effects on the growth and multiplication rate of potato explants.
Solanum tuberosum; phytotoxicity; micropropagation; antimicrobials; contamination
