Chen B Y, Simonsen V, Lannér-Herrera C, Heneen1 W K
Department of Plant Breeding Research, The Swedish University of Agricultural Sciences, S-268 31, Svalöv, Sweden.
Theor Appl Genet. 1992 Aug;84(5-6):592-9. doi: 10.1007/BF00224157.
Brassica campestris-alboglabra monosomic addition lines were developed from a trigenomic Brassica hybrid (2 n=3 x=29, AAC) obtained by backcrossing a resynthesized B. napus (2 n=4 x=38, AACC) line to its parental B. campestris (2 n=2 x=20, AA) line. One addition line was characterized genetically with three loci specific for the alien chromosome and cytologically by meiotic analysis. The following results were obtained. (1) The same chromosome in the B. alboglabra (2 n= 2 x=18, CC) genome carried the three loci, E c, W c and Lap-1 C (c), which control the biosynthesis of erucic acid, white flower colour and the faster migrating band of leucine aminopeptidase, respectively. The linear order and possible positions of the three loci were inferred. The meiotic behaviour of the alien chromosome was documented and its transmission frequency was assessed. (2) Intergenomic recombination frequently occurred in the monosomic addition line, resulting in the introgression of one or two loci from the alien chromosome into the B. campestris genome. (3) B. campestris trisomics were found in the progeny of the monosomic addition line. (4) The removal of the other eight C-genome chromosomes from the trigenomic Brassica hybrid led to a dramatic increase in the erucic acid content of the monosomic addition line. (5) No offspring of the trigenomic Brassica hybrid showed evidence of intergenomic recombination and introgression of the W c locus into the B. campestris genome. It is questioned whether such a difference might be due to a possible regulating mechanism for homoeologous chromosome pairing.
通过将人工合成的甘蓝型油菜（2n = 4x = 38，AACC）品系与其亲本白菜（2n = 2x = 20，AA）品系回交获得了一个三基因组芸苔属杂种（2n = 3x = 29，AAC），在此基础上培育出了白菜-白芥单体附加系。利用三个外源染色体特异位点对一个附加系进行了遗传鉴定，并通过减数分裂分析进行了细胞学鉴定。获得了以下结果。（1）白芥（2n = 2x = 18，CC）基因组中的同一条染色体携带了三个位点，即E c、W c和Lap-1 C（c），它们分别控制芥酸的生物合成、白花颜色以及亮氨酸氨肽酶的较快迁移带。推断了这三个位点的线性顺序和可能位置。记录了外源染色体的减数分裂行为并评估了其传递频率。（2）在单体附加系中频繁发生基因组间重组，导致一个或两个位点从外源染色体渗入白菜基因组。（3）在单体附加系的后代中发现了白菜三体。（4）从三基因组芸苔属杂种中去除其他八条C基因组染色体导致单体附加系的芥酸含量显著增加。（5）三基因组芸苔属杂种的后代均未显示出基因组间重组以及W c位点渗入白菜基因组的证据。有人质疑这种差异是否可能归因于同源染色体配对的一种可能调控机制。
