Regeneration of sorghum from shoot tip cultures and field performance of the progeny

A system for rapid plant regeneration through somatic embryogenesis from sh oot tip explants of sorghum [ Sorghum bicolor (L.) Moench] is described. So matic embryogenesis was observed after incubation of explants in dark for 6 -7 weeks through a friable embryogenic callus phase. Linsmaier and Skoog me dium supplemented with 2,4-dichlorophenoxyacetic acid (2 mg l(-1)) and kine tin (0.1 mg l(-1)) was used for induction of friable embryogenic calli and somatic embryos. Germination of somatic embryos was achieved about 5 weeks after transfer onto Murashige and Skoog (MS) medium supplemented with 6-ben zylaminopurine (2 mg l(-1)) and indole-3-acetic acid (0.5 mg l(-1)) under l ight. Seeds from in vitro-regenerated plants produced a normal crop in a fi eld trial, and were comparable to the crop grown with the seeds of the moth er plant used to initiate tissue culture. The simplicity of the protocol an d possible advantages of the system for transformation over other protocols using different explants are discussed.