Micropropagation from in vitro capitulum culture of several Gerbera jamesonii cultivars

Efficient bud multiplication was obtained from different clones of Garlenda; Leca; Massarosa; Mira; Nisida and Sirolo cultivars of Gerbera jamesonii. Fragment of young capitulum (diameter =1 cm) were used as primary explant to establish in vitro culture. Axillary buds of involucral bracts were grown after 30 days of culture, when a half strength MS salt medium with adenine sulfate, 80 mgl-1; AIA 0.1 mgl-1; BA 2 mgl-1 and sucrose 10 g/L were used as initial medium. Somatic embryos induced were arrested to the globular stage. Highest rate of axillary shoots (4-6:1) was accomplished when explants were transferred on MS medium added with IBA 0.05 mgl-1 BA 0,75 mgl-1 and GA3 0.1 mgl-1The multiplication step was developed during 18 month and during this period, abnormality formations were not observed. Seventy to 100 percent of rooted plantlets were obtained when 0.5 mgl-1 IBA were added to MS basal medium. Up to eighty percent of plantlets were successfully acclimated on greenhouses conditions and the morphology of adult plants were the same to the mothers plants. Not differences were observed when micropropagated plants flowered.

Key words: Gerbera jamesonii; micropropagation; capitulum explants; somatic embryogenesis, stability