浅析几个因子对甘蓝型油菜游离小孢子胚胎发生的影响

Analysis of Several Factors that Affect Isolated Microspore Embryogenesis in Brassica napus

为了快速纯舍杂交后代材料，提高重组基因型的选择几率，对40个杂交F1代组合进行小孢子分离培养。其中，有9个材料产生小孢子胚（占22.5％），仅4个材料（10.0％）获得了再生植株并种植大田，表明基因型是影响小孢子胚胎发生的一个主要因素。4个杂交组合材料的胚胎发生率为0.08～0.86胚／蕾，平均为0.25胚／蕾。细胞学检测表明，本试验杂交组合材料的最适取样花蕾长度为3.5mm。大田取样采取切取花序，然后在4℃冰箱中插水加散射光保存4～5d不影响胚胎发生。热激培养2d后小孢子的膨大率是衡量小孢子胚胎能否发生的一个有效指标。

Isolated microspore culture has greatly contributed to rapeseed haploid breeding, and is thus one of the most important technologies in rapeseed breeding and genetic engineering. Many parameters show effects on the in vitro microspore morphogenesis, and difficulties are encountered especially when microspore is collected directly from field-grown plants. The present isolated microspore culture used field-grown F1 plants from -t,0 cross combinations,in which 9 cross combinations produced embryos in culture （22.5% of total tested cross combinations） ,and plants regenerated in 4 cross combinations among them （10% of total tested cross combi-nations）. The ratio of the embryogenesis of the 4 cross combinations ranged 0.08-0.86 embryo/bud, at an average of 0.25 embryo/bud. Cytological analysis showed that the stage of flower bud at 3.5ram in length gave rise to the best embryogenesis. Branches with rachises collected from field-grown plants could be stored at 4℃ for 4-5 days in room light that facilitated lab analysis and culture. The percentage of microspore enlargement at 2 days after heat shock culture is an important marker for embryogenesis.