Somatic Embryogenesis and Plant Regeneration from Cultured Immature Embryos of Rye (Secale cereale L.).

Somatic embryogenesis was initiated in immature embryos of rye (Secale cereale L.) cultured on Murashige and Skoog's (1962) medium supplemented with various concentrations of 2,4-D and sucrose. The developmental stage of the embryo (optimal embryo length 0.5-2.0 mm) and concentration of 2,4-D (optimal concentration 2.5 mg · l(-1)) were found to be critical in determining embryo response. The phenoxyacetic acids, 2,4-D, 2,4,5-T, and MCPA were more effective in initiating embryogenic callus and embryoid formation than other auxins (NAA, IBA, IAA, IPA). Embryogenic callus and embryoid production was greater in embryos cultured scutellum up, and more embryoids were formed in the dark than in the light. Embryoids germinated after transfer to basal medium with/without cytokinin or GA3. The regenerated plants were grown to maturity in soil and were shown to have the normal diploid chromosome number of 14.