花生体细胞胚诱导及植株再生研究

为了建立花生体细胞胚诱导及植株再生体系，为花生分子育种提供技术支撑，以花生品种‘桂花30’和‘桂花771’为材料，采用预培养3天的种子胚小叶、下胚轴、子叶节为外植体，在添加外源激素的MS培养基中使体细胞脱分化形成体细胞胚，再分化成植株。结果表明，在所设定2,4-D浓度（3，5，10，15，20 mg/L）范围内，胚小叶最容易诱导形成体细胞胚，2,4-D的适宜浓度为10 mg/L，经过约30天培养，可产生大量体细胞胚，‘桂花30’和‘桂花771’的平均诱导率分别为55.37%和36.72%。平均每个外植体产胚量分别为5.68个和4.27个。将诱导形成的体细胞胚转接到6-BA浓度由5 mg/L逐渐降低到1.5 mg/L的MS培养基中，体细胞胚萌发再生成无根小苗，正常植株再生率‘桂花30’为32.6%，‘桂花771’为23.5%。将无根苗转接到生根培养基中可获得完整植株。花生是较难诱导体细胞胚形成的作物之一，筛选合适的基因型、外植体和激素浓度是获得较高体细胞胚发生率和植株再生率的关键技术。

The Study on Somatic Embryogenesis and Plantlet Regeneration of Peanut (Arachis hypogaea L.)

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 was 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.