| The fine peanut varieties, GUIHUA17, GUIHUA25, GUIHUA26and GUIHUA1026, which developed by Cash Crops Research Institute of Guangxi Academy of Agricultural Sciences, were used as test materials to develop high efficiency regeneration systems of peanut, for the purpose of peanut transgenic breeding. The involved factors included pre-cultured days, sources of explants, methods of explant cutting, sucrose concentration, the plant growth regulators and their concentration and genotypes of peanut, for somatic embryogenesis and organogenesis in peanut, respectively. The results are shown as below:1.There were different somatic embryogenesis and organogenesis efficiency for explants from different positions, respectively. Embryo leaflets could be more easily induced to produce adventitious bud and somatic embryos, but not for hypocotyl.2. The time and position of peanut embryo to cut explants are very important for inducing adventitious bud and somatic embryos. Parts dissected at the third of embryo leaflets near to the embryo leafletsstalk from three days pre-culture’s seeds could be used as explants to get the highest inductivity than other explants. The longer of the time of pre-culture of seeds, the less adventitious bud and somatic embryos to be induced due to higher differentiation and lignification.3.The culture medium with40g.L" sucrose was beneficial for peanut tissue culture.4.The type and concentration of plant growth regulators are critical for inducing adventitious bud and somatic embryos. The best inducing adventitious bud media consisted of MS+6mg/L6-BA+1mg/L NAA or MS+0.5mg/L TDZ+0.4mg/L NAA to get a inductivity of82.63%and75.56%, respectively. But The use of TDZ in the inducing period might be adverse with a less buds productivity of12.44%.The best inducing somatic embryo media was MS salts with10mg·L-2,4-D or5mg·L-Picloram. The higher concentration of plant growth regulators might produce browning of explants. Picloram could be used to induce fine callus, but get lower buds productivity of1.63%-2.59%.5.The appropriate media to develop adventitious buds was consisted of MS salts with2mg·L-6-BA and0.4mg·L-NAA, and MS salts with3mg·L-6-BA and0.4mg·L-NAA was good for developing seedlings from somatic embryos. The higher or less concentration of6-BA was not good for developing adventitious buds and seedlings of somatic embryos.6.NAA was needed to produce roots for the seedlings. Half of MS salts with3mg·L-NAA might be advantageous to produce roots with3or4roots per bud.7.The tested peanut varieties have different regeneration ability. The adventitious bud inductivity, buds productivity and root productivity of GUIHUA17are the highest among the tested varieties with82.63per cent and28.68per cent and77.14per cent, respectively, followed by GUIHUA26and GUIHA1026.The somatic embryo productivity and number,and buds productivity of GUIHUA26were the highest with45.83%,4.83%and35.71%,respectively,followed by GUIHUA1026,and no seedling produced with GUIHUA25.Bud productivity among the tested peanut varieties and growth regulators from embryo leaflets did not has significant difference with an average of4buds, but there was significant difference for the somatic embryo number with a range from2.19to4.83. |
