IN VITRO PROPAGATION OF DIONAEA MUSCIPULA ELLIS

摘要

In order to propagate vegetatively selected genotypes of Venus fly trap (Dionaea muscipula Ellis) with high ornamental value, a protocol for in vitro propagation was established that uses explants from mature plants. Young leaves with unfolded traps were submitted to surface disinfection. It was decisive to use sodium dichlorisocyanurat (NaDCC) as disinfectant by which damage to the plant tissue was minimized, while contamination rates were comparable to the treatments with sodium hypochlorite (NaOCl). The addition of activated charcoal to the medium during establishment to absorb phenolic compounds released by the explants was the second important adjustment. At the same time, the concentration of the cytokinin was increased tenfold (46.5 mu M kinetin). By this way, 20% of the explants were successfully established and about 5 adventitious shoots per explant were obtained after 60 days of culture. For axillary shoot multiplication, the growth of endophytic bacteria was to be controlled by plant preservative mixture (2 ml l(-1) PPM). Studying the effect of sucrose, nutrients, and kinetin concentration resulted in the following recommendation for propagation medium composition: half-strength MS medium with 15 g l(-1) sucrose and 0.5 mu M kinetin lead to a multiplication rate of about 10 shoots per explant. A separate rooting phase was not necessary, because the shoots readily rooted on the propagation medium. Acclimatization was accomplished without losses and within nine weeks of culture in the greenhouse, a soil coverage of 70% was reached indicating marketable plant size and quality.