Combining-ability analysis of somatic embryogenesis from epidermal layers in the sunflower (Helianthus annuus L.)

Crosses were made between three cytoplasmic male-sterile and five restorer sunflower inbred lines. F-1 hybrids, including their parents, were studied for their embryogenetic ability. Sterilized seeds were germinated in cultur e tubes on agar-solidified basal medium. Seven days after germination, epid ermal layers from hypocotyls were transferred into MS and B5 liquid-midia f or 5 and 8 days respectively. Then they were transferred to MS-120 solid-me dium with a high level of sucrose (120 g/l). The experimental design was co mplete randomized blocks with three replications. Each replication per geno type consisted of three Erlenmeyer flasks with 20-25 epidermal layers (expl ants), Analysis of variance indicated the presence of significant variation among genotypes for all traits studied. General combining ability (GCA) an d specific combining ability (SCA) showed significant effects for the studi ed traits. The highest value of GCA for the number of embryogenic explants per 100 explants plated (EE/100EP) belongs to parental female line 'CMS-PET 1 B9'. This inberd line also gave a high positive GCA effect for the number of embryos per ten embryogenic explants (E/10EE). Additionally, it had the highest values for EE/100EP and E/10EE (41.70 and 19.28 respectively) and should be a promising parent in crossing programmes for the enhancement of somatic embryogenesis in the sunflower. The highest values of specific comb ining ability (SCA) for EE/100EP and E/10EE belong to the F-1 hybrid 'CMS-P ET1B9 'x' RT1B11' which has produced 53.45 embryogenic explants/100 explant s and 9.67 embryos per ten embryogenic explants.