Plant regeneration from immature embryo and thin cell layer of pea(Pisum sativum L.) via callus induction, somatic embryogenesis and organogenesis

Two in vitro regeneration systems such as embryogenesis and organogenesis in pea (Pisum sativum L.) were established. The explants were prepared from embryos at four developmental stages corresponding to the pods collected based on DAP(day after pollination). The other explants were obtained from thin cell layers of epicotyl regions of in vitro-grown seedlings. The explants were cultured on MS+ B₅ (MSB) medium supplemented with various combinations of such growth regulators as BA, NAA, TDZ(thidiazuron), IAA, zeatin, 2, 4-D, and kinetin. The whitish-yellow embryogenic callus was derived from MSB medium supplemented with 2, 4-D 0.5㎎/ℓ and transferred to the same basal medium containing NAA 0.15㎎/ℓ, BA 0.33㎎/ℓ, kinetin 0.033㎎/ℓ, zeatin 0.033㎎/ℓ, glycine 0.02㎎/ℓ, and glutamine 0.06㎎/ℓ, where somatic embryos developed into plantlets. Plantlets from mature embryo culture showed a negative correlation between shoot number and the length of shoot and root depending on growth regulators and their concentrations. Seedlings with well-developed shoot and root system observed on the MSB medium containing 1.0㎎/ℓ zeatin and 0.05㎎/ℓ IAA were transferred to the pot for acclimatization and grown to maturity. Regenerated plants were also obtained through organogenesis when thin cell layer explants were cultured on MSB medium supplemented with BA 1.0㎎/ℓ and NAA 2.0㎎/ℓ or TDZ 0.3㎎/ℓ and NAA 0.05㎎/ℓ.