Long Term Stability of Electromanipulated Protoplasts of Glycine max var. Acme and a Catharanthus roseus Mutant

Protoplasts of soybean and an indole-alkaloid-free Madagascar periwinkle (vinca) were fused by electromanipulation. Callus cultures of these protoplasts were maintained in hormone-free semi-solid medium for nearly thirteen years. The stability of these cultures was tested by analysis of nuclear ribosomal DNA internal transcribed spacer (ITS) region. One fusion, out of the five finally tested, was regarded as exhibiting the characteristics of both the genomes from the original fused protoplasts while the others presented dominantly the ITS region of soybean.