Somatic Embryogenesis and Plant Regeneration in Evening Primrose (Oenothera biennis L.)

Callus induction responses and regeneration through callus-mediated SE were studied from evening primrose (Oenothera biennis L.) as an important medicinal plant of Onagraceae mainly known for its gamma-linoleic acid (GLA) content. The effects of cytokinins, 6-Benzylaminopurine (BAP) and N-(2 furfurylamino)1-H-purine-6- amine [Kinetin (Kin)] and their concentrations (0, 0.5, 1.0 and 1.5 mg/l) in combinations with 2,4- dichlorophenoxyacetic acid (2, 4-D) concentrations (0.25, 0.75 mg/l) on callus induction and SE for three explant types (petiole, leaf and epical bud) of "Shiraz" variety were separately evaluated. In all types of explants, the highest callus fresh weights belonged to 1 mg/l BAP or Kin in combinations with 2, 4 D (either 0.25 mg/l or 0.75 mg/l). The maximum fresh weight of callus was obtained from leaf explants plated on culture medium containing of 0.25 mg/l 2, 4-D and 1 mg/l Kin. The maximum The maximum number of embryos was achieved from leaf explants related to 0.75 mg/l 2, 4-D and 1 mg/l Kin. plantlets were successfully raised from in vitro developed embryos. Efficient plant regeneration via SE may provide a reliable system for studying the molecular mechanism of SE and a route for the genetic transformation of evening primrose.