TOWARDS AGROBACTERIUM-MEDIATED TRANSFORMATION OF HIPPEASTRUM X CHMIELII CHM. ¿ IDENTIFICATION OF APPROPRIATE SELECTION MEDIA
Hippeastrum species (Amaryllidaceae) have significant floricultural importance and are one of the major bulb crops in the commercial market. Amaryllidales are monocotyledonous plants that have been shown to be generally recalcitrant to molecular genetic manipulation. Successful plant transformation requires efficient regeneration and selection system and these were developed for a new hybrid Hippeastrum x chmielii Chm. This hybrid shows very vigorous growth and flowers without undergoing a quiescent phase. In preparation of transformation experiments the aim of this study was to establish appropriate media for selecting transgenic cells/regenerants. Therefore, the effect of different concentrations of glufosinate (syn. phosphinothricin) on plant regeneration and propagation were analyzed. Glufosinate will be used in transformation experiments to select the cells expressing the pat gene. In addition the influence of cefotaxim, an antibiotic used for suppression of agrobacteria after co-culture, on the selective efficiency of glufosinate was tested. Two different kinds of explants were used: first, young flower stalk segments cultured on MS medium with 2 mg L-1 2iP and 0.2 mg L-1 NAA, and second quarters of in vitro bulblets on MS medium with 0.5 mg L-1 BA and 0.1 mg L-1 NAA. Glufosinate totally inhibited bulblet formation for both types of explants even at low concentrations of 1.0 mg L-1 to 2.0 mg L-1. Therefore, this level was found to be suitable for being used in the selection medium. The addition of 500 mg L-1 cefotaxim did neither inhibit regeneration nor did it interfere with the selective efficiency in glufosinate containing medium. The results obtained in this study are the basis for establishing an Agrobacterium-mediated transformation system. By genetic transformation Hippeastrum x chmielii Chm. can be improved regarding flower longevity or disease resistance.
Ilczuk, A., Lukaszewska, A., Winkelmann, T. and Serek, M. (2006). TOWARDS AGROBACTERIUM-MEDIATED TRANSFORMATION OF HIPPEASTRUM X CHMIELII CHM. ¿ IDENTIFICATION OF APPROPRIATE SELECTION MEDIA. Acta Hortic. 725, 795-800
breeding, cefotaxim, gene transfer, glufosinate, in vitro, phosphinothricin, regeneration