This study presents the results of experiments concerning: (1) interspecific hybridization of Brassica oleracea × Brassica rapa via application of in vitro placental pollination and (2) embryological analysis of the process of resynthesis of Brassica napus. In order to overcome certain stigma/style barriers, B. rapa pollen was placed in vitro on an opened B. oleracea ovary (with style removed). Pollinated ovaries were cultured on Murashige and Skoog (MS) medium. After 24-d culture, the developing embryos were isolated from immature seeds and transferred onto MS medium supplemented with 0.47 μM kinetin, 0.49 μM 1-naphthaleneacetic acid, and 10% (v/v) coconut water. When the embryos had turned green, they were immediately placed onto MS medium with 100 μM kinetin. After development of the seedling, plantlets were transferred to soil. Chromosome doubling was achieved after another week. Cytometric analysis of nuclear DNA confirmed the hybrid nature of the plants. Resynthesis of B. napus can be performed through interspecific hybridization of B. oleracea × B. rapa followed by embryo rescue and genome doubling.

中文翻译：

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应用开放卵巢离体授粉获得甘蓝×B. rapa L.杂种。

本研究介绍了以下实验的结果：(1) 甘蓝 × 油菜通过体外胎盘授粉的种间杂交和 (2) 甘蓝型油菜再合成过程的胚胎学分析。为了克服某些柱头/花柱障碍，将油菜花粉放在体外打开的甘蓝子房（去除花柱）上。授粉的卵巢在 Murashige 和 Skoog (MS) 培养基上培养。培养 24 天后，从未成熟的种子中分离发育中的胚胎并转移到添加了 0.47 μM 激动素、0.49 μM 1-萘乙酸和 10% (v/v) 椰子水的 MS 培养基上。当胚胎变绿时，立即将它们置于含有 100 μM 激动素的 MS 培养基上。幼苗发育后，将幼苗转移到土壤中。又过了一周，染色体加倍。核 DNA 的细胞计量分析证实了植物的杂交特性。B. 油菜的再合成可以通过 B. oleracea × B. rapa 的种间杂交进行，然后进行胚胎拯救和基因组加倍。