Somatic Embryogenesis for Mass Propagation of Ericaceae – A Case Study with Leucopogon verticillatus

Abstract

An efficient three-phase culture has been developed for plant regeneration of Leucopogon verticillatus (R. Br.) (Ericaceae formerly Epacridaceae [Ann. Missouri Bot. Gard. 85 (1998): 531–553]) via somatic embryogenesis as indicative of likely culture scenarios for other Ericaceae. The Ericaceae, particularly many Australian species, are often difficult to propagate by conventional forms of nursery propagation. Initiation of somatic embryos was best achieved using Gamborg’s B5 medium, pH 6, 4% maltose, 0.7% agar with the plant growth regulators 10 µM TDZ and 5 µM IAA. Somatic embryos were removed from the parent tissue and transferred to half strength basal GB5 medium for elongation. Root development did not occur unless specific treatments were used, a 2–5 day pulse treatment of 100 µM IBA significantly increased root production. All roots produced in agar-medium were fine and easily damaged when removed from culture. The most successful rooting medium (>60%) was sand on oat medium, which facilitated easy removal from the substrate and improved the survival of plants when transferred to soil.