Abstract
Experiments were carried out to develop micropropagation protocols for cultivars of hybrid origin which have been not cultivated via tissue culture. Proliferating cultures of Pelargonium × domesticum “Tip Top Duet” and “Black Knight” were obtained even if initially the number of excised aseptic nodal pieces was considerably reduced due to contamination with endogenic bacteria. The supplementation of a maintenance medium with either 100 or 200 mg/l peptone proved beneficial. The best propagation coefficient, exceeding 82 adventitious shoots from one initial microcutting, was obtained on a modified MS medium with an addition of 200 mg/l peptone and 0.5 mg/l adenine. The regenerated shoots readily developed new, anatomically properly formed leaves. In the plant material studied, the leaf epidermis produced glandular trichomata which were similar in structure to those observed in a standard cultivar.