Abstract
Stem tips of Zantedeschia hybrida ‘Black Magic’ were inoculated onto solid MS medium containing ABM1 (SIGMA ; antibiotics mixture) in vitro. A great majority of the explants became contaminated by endogenous bacteria. For comparison, sections of the tuber bearing a bud were soaked in ABM 1 solution for 5 d, and then stem tips were excised and planted onto MS medium. This treatment also showed no effect in suppressing contamination. In a third set of treatments, tubers bearing 2-3 foliage leaves were soaked in silver nitrate solutions (0.02-2.0 g L-1) and then stem tips were excised and planted on MS medium. A 24-h treatment in 0.2 g L-1 silver nitrate solution reduced the outbreak of endogenous contamination by 14%.
