幼胚发育阶段对次郎柿胚抢救效果的影响

Effect of embryo development stage on embryo rescue for Jirou persimmon culitivar

迄今对柿幼胚培养的最佳时期尚不完全明确。以完全甜柿品种次郎(Diospyros kaki Thunb.cv.Jirou)为试材,探讨了幼胚发育阶段对胚抢救效果的影响。结果表明,(1)授粉后40d幼胚处于球形胚期,50d处于心形或鱼雷形期,60d之后处于子叶形胚期;(2)接种授粉后40d幼胚的萌发率(29.3%)显著低于其它时期,其后不同取胚时期的萌发率均为100%,差异不显著;(3)接种授粉后60d幼胚的成苗率(92%)显著高于其它时期,再生植株苗高和生根数与其它时期无明显差异。因此,心形期至子叶期阶段是完全甜柿品种次郎幼胚的最佳培养时期,萌发率和成苗率分别为100%和86%～92%。该时期较前人报道的柿幼胚培养时期提早10￣20d。

The optimum stage for embryo rescue in persimmon （Diospyros kaki Thunb.）is not very clear up to now. Embryos from 40 days after pollination （DAP） to 80 DAF were cultured in vitro and the effect of embryo germination and plantlets regeneration were compared. Results showed as follows, on 40 DAP, embryos were at globular stage. At 50 DAP, heart and torpedo embryos were found. Embryos were at the stage of cotyledon from 60 DAP. The rate of germination （29.3%） of globular embryos on 40 DAP was significantly less than embryos at other stages, and all embryos after heart stage germinated 100%. The plantlet regeneration percentage of 60 DAP was 92% which was the significantlyhigher than other four stages. The effect of five embryo stages on the height of seedlings and number of seedling roots was similar. So the optimum stage for embryo rescue in persimmon was from heart stage to cotyledon stage which was 50 to 60 DAP in Wuhan, Hubei province, ahead of 10 to 20 days than that of previous reported. Embryo germination and plant regeneration at these stages reached 100% and 86% to 92%, respectively.