Tan Chen, Cui Cheng, Xiang Yi, Ge Xianhong, Li Zaiyun
National Key Lab of Crop Genetic Improvement, National Center of Oil Crop Improvement (Wuhan), College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
Research and Development Centre of Flower, Zhejiang Academy of Agricultural Sciences, Hangzhou, 311202, People's Republic of China.
Theor Appl Genet. 2017 Dec;130(12):2491-2504. doi: 10.1007/s00122-017-2971-8. Epub 2017 Sep 7.
We report the development and characterization of Brassica oleracea - nigra monosomic alien addition lines (MAALs) to dissect the Brassica B genome. Brassica nigra (2n = 16, BB) represents the diploid Brassica B genome which carries many useful genes and traits for breeding but received limited studies. To dissect the B genome from B. nigra, the triploid F hybrid (2n = 26, CCB) obtained previously from the cross B. oleracea var. alboglabra (2n = 18, CC) × B. nigra was used as the maternal parent and backcrossed successively to parental B. oleracea. The progenies in BC to BC generations were analyzed by the methods of FISH and SSR markers to screen the monosomic alien addition lines (MAALs) with each of eight different B-genome chromosomes added to C genome (2n = 19, CC + 1B), and seven different MAALs were established, except for the one with chromosome B2 which existed in one triple addition. Most of these MAALs were distinguishable morphologically from each other, as they expressed the characters from B. nigra differently and at variable extents. The alien chromosome remained unpaired as a univalent in 86.24% pollen mother cells at diakinesis or metaphase I, and formed a trivalent with two C-genome chromosomes in 13.76% cells. Transmission frequency of all the added chromosomes was far higher through the ovules (averagely 14.40%) than the pollen (2.64%). The B1, B4 and B5 chromosomes were transmitted by female at much higher rates (22.38-30.00%) than the other four (B3, B6, B7, B8) (5.04-8.42%). The MAALs should be valuable for exploiting the genome structure and evolution of B. nigra.
我们报道了甘蓝型油菜-黑芥单体异附加系（MAALs）的培育和特性分析，以剖析甘蓝型油菜的B基因组。黑芥（2n = 16，BB）代表二倍体甘蓝型油菜B基因组，其携带许多用于育种的有用基因和性状，但相关研究有限。为了从黑芥中剖析B基因组，先前通过甘蓝型油菜变种白叶甘蓝（2n = 18，CC）×黑芥杂交获得的三倍体F杂种（2n = 26，CCB）被用作母本，并连续回交至亲本甘蓝型油菜。通过荧光原位杂交（FISH）和简单序列重复（SSR）标记方法对BC1至BC4代的后代进行分析，以筛选出将八条不同B基因组染色体中的每一条添加到C基因组（2n = 19，CC + 1B）的单体异附加系（MAALs），并建立了七个不同的MAALs，除了含有B2染色体的那个存在于一个三体附加系中。这些MAALs中的大多数在形态上彼此可区分，因为它们以不同程度表达了来自黑芥的性状。在终变期或中期I，外源染色体在86.24%的花粉母细胞中以单价体形式保持未配对，在13.76%的细胞中与两条C基因组染色体形成三价体。所有添加染色体通过胚珠的传递频率（平均14.40%）远高于花粉（2.64%）。B1、B4和B5染色体通过雌性传递的速率（22.38 - 30.00%）远高于其他四条（B3、B6、B7、B8）（5.04 - 8.42%）。这些MAALs对于探索黑芥的基因组结构和进化应该具有重要价值。
