The impact of a pulse treatment of penicillin-G and streptomycin sulfate on sporophyte regeneration of Platycerium bifurcatum.

This study was aimed at investigating the impact of antibiotic pulse treatment (APT) of penicillin-G and streptomycin sulfate at a concentration of 1000 mg/l each on the regeneration ability of leaf and shoot-base explants and homogenized sporophytes of Platycerium bifurcatum. The reaction of the plant to APT, as measured by changes in sporophyte regeneration and morphology, was considered to be a stress response. Cell's susceptibility to APT was graded as: tissue homogenized prior to treatment>tissue homogenized after treatment>leaf and shoot-base explants. Biphasic inhibition in sporophyte regeneration was observed in homogenized sporophytes; a sharper decrease occurred with 20-60 min of the APT, followed by a slower decline for up to 180 min. No significant impact on the regeneration ability of leaf and shoot-base explants was found. Morphologically, APT caused leaf cleavage, mesophyll damage and hyperhydricity in some sporophytes. Except for the hyperhydric sporophytes, regenerants were able to continue their growth in soil, and no carry-over effect was found in the next generation.