Micropropagation In Vitro Of Agapanthus Praeco Ssp.Orientalis 'Big Blue'

Micropropagation system was established in Agapanthus praecox ssp.orientalis'Big Blue'which originated from South African in this thesis. Filtration of suitable explants, induction of mature embryos and plantlets domestication were done in the developmental pathway of somatic embryogenesis. At the same time histological observations were researched. The developmental pathway of organogenesis included the induction of callus, adventitious buds and plantlets domestication. The results were as the followed:1. Seed germination rate of pretreatment with removing seed wing and adding detergent was 42.2% and higher than non-pretreatment.2. The optimizing medium for inducing callus from pedicel was MS+6-BA1.5mg/L+Citric acid0.1mg/L and the induction rate was 13.33%. However, the induction rate was 56.7% from adventitious buds on the optimizing medium containing MS+6-BA1.5 mg/L+IBA0.2mg/L. Pedicel as explants is limited seriously by sampling time, so it could not achieve the requirements of industrialization.3. Caudexes, leaves and pedicels were used as explants in somatic embryogenesis and the results indicated that regeneration ability of caudexes was the best after filtration and original culture. The optimizing medium for inducing callus with caudexes was MS+PIC0.5mg/L and the induction rate was 53.33%. But the most appropriate medium for pedicels was MS+PIC3.0mg/L and the induction rate was 53.33%. The optimizing medium for leaves was MS+PIC2.0mg/L+6-BA0.4mg/L and the induction rate was 40.00%. Considering the sample collection, callus induction rate and experiment cost, caudex was the most suitable explant.4. The callus growed quickly and best on the medium of MS+PIC1.0mg/L. Fluffy, viscous, yellowish and translucent callus was gained after subculture. According to research reports it was embryogenic callus.5. It was proved for the first time that embryogenic callus of Agapanthus should be subcultured in every three or four weeks during the proliferation phase by the growth curve.6. Club-shaped and globular embryoids were induced on mature medium and globular embryoids could generate secondary embryos. Both club-shaped and globular embryoids could develop into normal plantlets. MS+6-BA0.1mg/L+Sugar45g/L was the suitable medium for inducing embryoids. On average 722 embryoids were formed per ca. 1g FW(fresh wight) of the calli.7. The best medium for rooting was 1/2MS+IBA0.l5mg/L and the roots were healthy and strong.. Health plantlets were chosen to be transferred when they were 2-3cm-high and the survival rate reaehed 98.5% with proper light and humidity.8. Compared to Gramineae, the developmental pathway of somatic embryogenesis and organogenesis might exist in the same culture of Agapanthus praecox ssp.orientalis'Big Blue'. The observation of cell microstructure from proliferation to mature embryo induction was first reported systematically and could be a diagnose marker for the somatic embryogenesis.9. The somatic embryogenesis of Agapanthus was firstly established with caudex as explant in china and laid theoretical and practical foundation for the industrial production technology of Agapanthus.