萝卜和甘蓝远缘杂交研究

Studies on intergeneric hybridization between Raphanus sativus and Brassica oleracea

以4个栽培萝卜(Raphanus sativus,2n=18,RR)分别和芥蓝(Brassica oleraceavar.alboglabra,2n=18,CC)、苤蓝(Brassica oleraceavar.acephala,2n=18,CC)杂交,研究萝卜和甘蓝的杂交亲和性。萝卜×甘蓝受精前亲和性低,只有极少数甘蓝花粉粒能在萝卜柱头上黏附、萌发,延伸到花柱,到达胚珠。母体内杂种胚很多能发育成熟,平均每杂交100朵花得到杂种3.9株,说明萝卜×甘蓝生殖隔离主要发生在受精前,受精后障碍相对较轻。甘蓝×萝卜受精前亲和性高,萝卜花粉能在甘蓝柱头上正常萌发、延伸,但采用常规的人工去雄杂交方法没有得到杂种,而用幼胚离体培养获得了杂种,表明甘蓝×萝卜生殖障碍主要发生在受精或受精后。

The intergeneric hybrids between radish （Raphanus sativus ,2n = 18, RR） and cabbage （ Brassica oleracea, 2n = 18, CC） were obtained by hand cross and embryo rescue. It was found that the hybrids were more difficulty obtained when cabbage acted as the maternal plant than acted as the paternal plant. Pollen grain germination and pollen tube growth were investigated in those hybridization. In the combination of radish × cabbage, the misogamy happened before spermatization, few cabbage pollen grains could germinate on radish stigma. But the hybrid embryo developed easier in the living plant than in isolated culture once germination happened. In the combination of cabbage × radish, radish pollen grains were compatible to the cabbage pistil, but the hybrid embryos hardly developed in the maternal plant. So ovary culture or embryo culture should be used.