二步培养和AgNO3对甘蓝型油菜子叶和下胚轴芽再生的影响

以甘蓝型油菜（Brassica napus L．）品种浙双758为材料，研究二步培养及添加AgNO3对甘蓝型油菜子叶和下胚轴外植体离体再生的影响。外植体先在含0．5—1．5mg／L2，4-D的MS培养基上预培养3d或7d诱导愈伤组织的产生，再转到含有3mg／LBA和0．15mg／LNAA及添加或不添加2．5mg／LAgNO3的分化培养基上诱导芽的分化。结果表明，外植体愈伤组织诱导率和芽再生率与2，4-D浓度、预培养时间和AgNO3密切相关；分化培养基中添加银离子可显著增加不定芽的再生频率；二步培养及添加AgNO3可使半子叶、完整子叶和下胚轴外植体芽再生频率分别达到了96．1％，96．7％和96．7％。

Effect of two-step culture and AgNO3 on the shoot regeneration from cotyledon and hypocotyl explants in Brassica napus

The influence of two-step culture and AgNO3 on the shoot regeneration frequency from cotyledon and hypocotyl explants in oilseed rape （Brassica napus L. ） cv. Zheshuang 758 had been studied. Explants were pre-cultured 3 or 7 days in the media containing 2,4 - D with different concentration （0.5 - 1.5mg/L） to induce embryogenesis, the explants were then transferred to shoot differentiation medium supplemented with 3 mg/L BA, 0.15 mg/L NAA,with or without 2.5mg/L AgNO3 to induce shoot regeneration. The results showed that the callus induction frequency and shoot regeneration frequency were positively correlated with 2,4 - D concentration, pre-cultivation time and AgNO3. The shoot regeneration frequency was greatly improved by two-step culture procedure and added AgNO3. The maximal shoot regeneration frequency was 96.1% ,96.7% and 96.7% respectively from half-cotyledon,intact-cotyledon and hypocotyls explants in rape seed.