Abstract: Both the percentages of ovules producing embryoids and the mean number of embryoids per ovule were higher when the undeveloped ovules from mature fruits of two cultivars of sweet orange (Cirtus sinensis), Blood orange and Jincheng orange, were cultured on MT medium added with 100 mg/L malt extract (ME). The embryogenic characteristics could be retained if the callus and embryoids were transferred and subcultured on the same medium. The percentage of established plantlets were higher when the cotyledon-shaped embryoids were transferred to MT mediumsup-plemented with 2 mg/L gibberelic acid (GA) and 500 mg/L casein hydro-lysate (CH). The results from this study presents a new approach for extending the source of explants and solving the problem of seasonal limit of excising explant in citrus tissue culture.

Key words: Citrus sinensis, Undeveloped ovule, In vitro culture, Embryo-genesis

摘要： 路比血橙和锦橙成熟果实的未发育胚珠在含ME(1000 mg/l)的MT培养基上培养,胚状体诱导率和每个胚珠平均产生胚状体数均较高。带胚状休的愈伤组织转入该培养基上继代培养,仍可保持其胚性特点。将子叶形胚状体转至含GA(1 mg/l)和CH(500 mg/l)的MT培养基上,成苗率较高。这为扩大柑桔组织培养的外植体来源和克服外植体的季节限制提供了新途径。

关键词: 甜橙, 未发育胚珠, 离体培养, 胚胎发生