Somatic hybrid plants produced by electrofusion between Solanum melongena L. and Solanum torvum Sw

Somatic hybrid plants between eggplant (Solanum melongena) and Solanum torvum have been produced by the electrofusion of mesophyll protoplasts in a movable multi-electrode fusion chamber. Using hair structure as a selection criteria, we identified a total of 19 somatic hybrids, which represented an overall average of 15.3% of the 124 regenerated plants obtained in the two fusion experiments. Several morphological traits were intermediate to those of the parents, including trichome density and structure, height, leaf form and inflorescence. Cytological analyses revealed that the chromosome numbers of the somatic hybrids approximated the expected tetraploid level (2n=4x=48). Fifteen hybrid plants were homogeneous and had relatively stable chromosome numbers (46-48), while four other hybrids had variable chromosome numbers (35-48) and exhibited greater morphological variation. The hybridity of these 19 somatic hybrid plants was confirmed by analyses of phosphoglucomutase (Pgm) and esterase zymograms.