黄瓜游离小孢子培养诱导成胚和植株再生

 以10个不同基因型黄瓜为试材进行游离小孢子培养，通过对成胚条件的系统研究，从‘7447’和‘Poinsett97’中获得了子叶形胚和再生植株。研究结果表明：基因型和小孢子发育时期是限制黄瓜游离小孢子成胚的关键因子。不同品种间胚状体产量差异显著，每皿产胚1.5～33.4个。单核靠边期是进行黄瓜游离小孢子培养的最佳时期。低温预处理有利于胚状体的诱导，4 ℃预处理2～4 d为宜，以处理2 d时胚状体产量最高。外源激素在诱导胚状体时并非必需，但低浓度的外源激素（0.5 mg·L^-1 2,4－D、0.2 mg·L^-1 6－BA）更能促进小孢子成胚。NLN和B5两种基础培养基在诱导胚状体上无显著差异。子叶形胚易分化成苗，而其它类型的胚状体不能获得再生植株。

Embryoid Induction and Plant Regeneration of Cucumber (Cucumis sativus L.) Through Microspore Culture

Isolated microspore culture in cucumber was studied by using 10 different varieties of cucumber. Cotyledonary embryoids and plantlets were obtained from '7447' and 'Poinsett97' genotypes for the first time. The results showed that genotype and the developmental stage of microspore were the key factors in embryoid induction. The embryoid yield was different significantly among different genotypes. Embryoid yield per culture dish varied from 1.5～33.4. The late-uninucleate stage of microspore was found optimum for isolated microspore culture in cucumber. Cold-pretreatment (4 ℃) for 2～4 days also promoted embryoid induction, while the highest embryoid yield was obtained form microspore pre-treated at 4 ℃ for 2 days. The results also indicated that low concentration of exogenous hormones (0.5 mg·L^-1 2,4-D and 0.2 mg·L^-1 6-BA) were conductive to embryogenesis, whereas NLN and B₅ medium had no significant difference on embryoid induction. The regenerated plantlets were obtained only from cotyledonary embryoids and no plantlet was produced from the embryoids at other developmental stages.