桃幼胚下胚轴高频植株离体再生

以桃品种京艳和晚蜜不同发育阶段合子胚下胚轴为外植体进行离体培养,用6-BA、CPPU和TDZ等细胞分裂素诱导下胚轴直接再生不定芽试验。结果表明,花后70d下胚轴为诱导的最佳材料,供试细胞分裂素中,诱导活性为TDZ>CPPU>6-BA,苯脲类细胞分裂素TDZ5mg/L与NAA0.01mg/L配合对下胚轴再生具有极强的诱导作用,京艳诱导再生率高达95.2%,平均不定芽数达每外植体25.3个。京艳的诱导率显著高于晚蜜。IBA 0.5mg/L适于诱导再生幼茎的生根,生根率和移栽成活率分别达到92.6%和65.5%。组织学观察表明不定芽起源于皮层薄壁细胞,属直接再生方式。

High Regeneration of Adventitious Shoots from Hypocotyl of Peach (Prunus persica L.)

Hypocotyl segments from zygotic embryos of peach cultivar Jingyan and Wanmi were used as explants to induce adventitious shoots with different cytokinins,6-BA,CPPU,and TDZ. The results showed that TDZ was more effective than 6-BA and CPPU in stimulating adventitious shoots regeneration,reached as high as 95.2% of differentiation rate and 25.3 buds per hypocotyl were obtained in Jingyan. Regeneration potential of hypocotyl is closely dependent on the developmental stage of embryos; the optimal response was obtained in embryos collected at 70 d after full bloom. Histological observation showed adventitious buds were originated directly from parenchyma cells under epidermis without callus phase. Jingyan is more responsive to cytokinins than Wanmi. IBA0.5 mg/L was suitable for regenerated shoots to root, 92.6% rooting rate and 65.5% survival rate in greenhouse could be obtained.