甘蓝型油菜和诸葛菜属间杂种的获得及其特性

采用人工授粉并结合子房培养的方法,进行了甘蓝型油菜和诸葛菜的正反属间杂交。授粉后5~10d,取子房培养于MS或B5培养基(添加6-BA、NAA、水解酪蛋白和活性碳),结果表明,子房培养有助于提高甘蓝型油菜和诸葛菜属间杂种获得频率。不同杂交组合,属间杂交可交配性不同。以诸葛菜为母本的所有杂交组合没有获得成功,但是在以甘蓝型油菜为母本的正交组合中获得了18株属间杂种,其中8株在形态上近似母本湘油15,10株来自于742与诸葛菜杂交组合,表现出完全的雄性不育,幼苗期叶色浅黄,生长发育缓慢,植株矮小,花瓣呈现乳白色,第一次分枝数少且分枝部位较高。形态学和微卫星标记分析表明,这些植株是真正的属间杂种。杂种后代植株(F2代或回交一代)表现多型性,多数植株的性状倾向母本甘蓝型油菜,可育;部分植株表现为双亲的中间型,部分可育;少数植株发育缓慢,不育。这些杂种植株可能是油菜遗传改良的宝贵资源。

Production and Characterization of Intergeneric Hybrids between Brassica napus and Orychophragmus violaceus

Intergeneric reciprocal hybridization between B. napus and O. violaceus were conducted to introduce desirable traits of O. violaceus into cultivated Brassica species by manual pollination and ovary culture. The ovaries pollinated were cultured on MS or B5 medium supplemented with various plant hormones at 5～10th day after pollination,the results showed that ovary culture helped to obtain the intergeneric hybrids from the crosses B. napus ×O. violaceu,and great differences on the intergeneric crossability were found among cross combinations. All reciprocal crosses failed,but 18 hybrid plants was obtained in the direct crosses,eight of which were similar to female parent B.napus,ten plants from the cross 742(B.napus,2n=38,AACC)×O.violaceus exhibited traits which were not observed in the parents,such as slightly yellowish leaf in young hybrid,slow growth,dwarf,creamy white petal,fewer number of primary branches and higher branching positions and complete male sterile. Morphology and analysis of microsatellite markers proved that the hybrids were validated to be real intergeneric hybrid obtained through ovary culture. The hybrid offsprings (F_2 or BC_1) showed polymorphism.among the hybrid offsprings,most of them were nearly matroclinous and fertile,similar to B. napus,some were intermediate between the two parents showing partially fertile,and a few were poorly developed and male sterile. The hybrids should be valuable resource for the genetic improvement of oilseed grape.