INITIATION AND STABILIZATION OF A TRUMPET CREEPER (Campsis radicans (L.) Seem.) TISSUE CULTURES

A trumpet creeper (Campsis radicans) is a very decorative shrub propagated vegetatively through cuttings. So far, there is no available information on micropropagation of this beautiful species. Determination of the optimal sterilization methods as well as types and concentrations of plant growth regulators as medium constituents is one of the most important factors of successful micropropagation. With the aim of optimization of in vitro initiation and multiplication of C. radicans, the effect of different methods of disinfection and terms of explants isolation on contamination rate of cultures as well as the influence of cytokinins on growth and branching of shoots was studied. The cytokinins used in the experiments were: benzyladenine (BA), isopentenyl adenine (2-iP) and kinetin (KIN). The obtained results show that contamination rate is a very significant problem to overcome in order to initiate tissue cultures of C. radicans. The best results were observed when explants were excised in spring (May), shortly after the vegetation had started (88% contamination rate). Soaking initial the fragments in a mixture solution of Topsin M 500SC and streptomycine for 12 hours decreased the contamination rate of explants from 100 to 94%. The shoot tips are more suitable to establish the tissue culture of a trumpet creeper, in comparison to nodes with axillary buds. The multiplication rate after two subcultures was 2.6-3.7 for shoot tips (depending on the media) and 1.9-2.1 for nodes. The cytokinins used in the experiment had a significant influence on multiplication rate of C. radicans. The highest number of good quality shoots was obtained on the media supplemented with KIN in concentration of 2 mg.dm(-3).