Esterase and peroxidase isoforms in different stages of morphogenesis in Fritillaria meleagris L. in bulb-scale culture.

Morphogenesis in vitro is a complex and still poorly defined process. We investigated esterase and peroxidase isoforms detected in bulb scale, during Fritillaria meleagris morphogenesis. Bulbs were grown either at 4 °C or on a medium with an increased concentration of sucrose (4.5%) for 30 days. After these pre-treatments, the bulb scales were further grown on nutrient media that contained different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and kinetin (KIN) or thidiazuron (TDZ). Regeneration of somatic embryos and bulblets occurred at the same explant. The highest numbers of somatic embryos and bulblets were regenerated on the medium containing 2,4-D and KIN (1mg/L each), while morphogenesis was most successful at a TDZ concentration between 0.5 and 1mg/L. Monitoring of esterases and peroxidases was performed by growing bulb scales on a medium enriched with 2,4-D and KIN or TDZ (1mg/L), and the number and activity of isoforms were followed every 7 days for 4 weeks. In control explants, six isoforms of esterase were observed. Three isoforms of peroxidase were not detected in the control bulb scale, which has not begun its morphogenesis process.

Indirect somatic embryogenesis from petal explant of endangered wild population of Fritillaria imperialis.

Fritillaria imperialis is an endangered bulbous plant and therefore in vitro micropropagation of this plant will have a great importance for germplasm conservation and commercial production. Petal explants, for the first time, were cultured on media containing various concentrations of plant growth regulators. In addition, the effects of cold pretreatment and light on induction and regeneration of somatic embryogenesis trough callus were studied in detail. Cold pretreatment had inhibitory effects on somatic embryogenesis pathway. Among the different combinations of 6-Bnzylaminopurine (BAP), alpha-naphthaleneacetic acid (NAA) and indole-3-aceticacid (IAA) tested, B5 medium supplemented with 0.1 mg L(-1) BAP + 0.6 mg L(-1) NAA + 0.4 mg L(-1) IAA was the best treatment for bulblet production (6 bulblets per somatic embryogenesis callus). This research presents petal as a reliable material for micropropagation and germplasm conservation of Fritillaria imperialis.