SOMATIC HYBRIDIZATION BETWEEN LYCOPERSICON-ESCULENTUM AND NONTUBEROUS SOLANUM SPECIES OF THE ETUBEROSA SERIES

Intergeneric somatic hybrid plants have been obtained by protoplast fusion between leaf mesophyll protoplasts from two cultivars of tomato (cv. Tamina and plastome mutant Pl-alb I) and mesophyll protoplasts from two representatives of the Etuberosa series of the genus Solanum (wild species S. etuberosum and sexual interspecific hybrid S. brevidens x S. etuberosum). A hybrid selection scheme was based on the faster growth of hybrid microcalli in comparison with parental calli and on the morphological characteristics of hybrid calli and hybrid regenerants. Hybridity was confirmed by morphological and cytological characteristics, esterase and peroxidase isozyme analyses. Somatic hybrids were also characterised by Southern hybridization of the 5,3 kb probe of the tomato meiotic gene mL-I. Twelve out of sixty hybrids produced fruits after selfing; however, their fruits had abortive seeds. Three progeny plants were obtained via embryo culture after selfpollination of intergeneric somatic hybrids.