Plant regeneration from the protoplasts of Solanum tuberosum, S-nigrum andS-bulbocastanum

The mesophyll protoplasts were isolated from the Solanum tuberosum (S. tbr) clones of different ploidy level (4x Bzura cv., 2x H-8105, and 2x ZEL-1136 ) as well as from the wild species: S. bulbocastanum (S. blb, 2x) and two a ccessions of S. nigrum (S. ngr, 6x). Additionally, the protoplasts were iso lated from the cell suspensions of B Bzura cv, and H-8105 clone. The condit ions of protoplast isolation as well as the media for their culturing and r egeneration, were selected and optimized for the studied genotypes. For mes ophyll protoplasts, the shooting calli were produced by all the cultured pr otoclones except that of S. bulbocastanum. The shoots excised from the prot oplast-derived calli developed into whole plants in all the studied potato clones but only in one accession of S, nigrum, i.e. S. ngr var. gigantea. A s for suspension-cell-derived protoplasts, only H-8105 clone produced the r egenerative type of calli, though normal shoots could not be obtained. The regenerative capacity of the protoplasts isolated from leaves and cell susp ensions is compared and discussed.