Abstract:

In order to establish a molecular breeding protocol for peanut, a reliable and highly efficient method for the regeneration of intact plants from in vitro culture is essential. In the current study, a protocol was developed for somatic embryogenesis and plant regeneration from embryo leaflet cultures using 2,4-dichlorophenoxyacetic acid (2,4-D), which 'Guihua 30' and 'Guihua 771' were used as the test varieties. It was found that the embryo leaflets as explants were more effective for induction of somatic embryos. Nevertheless, in the tested five cases, 2,4-D at 10 mg/L was optimally effective for maximum induction of somatic embryos per explant, with an average of 5.68 for 'Guihua 30' and 4.27 for 'Guihua 771'. After germination of somatic embryos, regenerated plantlets were recovered on Murashige and Skoog (MS) medium with 6-benzylaminopurine in concentrations from 5 mg/L to 1.5 mg/L, with a plantlet regeneration rate of 32.6% for 'Guihua 30' and 23.5% for 'Guihua 771'. Peanut is one of the crops which are difficult to induct somatic embryos, and further study may be needed to find out more favorable genotypes and explants and plant growth hormones with optimal concentration for the regeneration of peanut transgenic plants.