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虽然芸薹属栽培种的3个二倍体祖先,白菜型油菜(AA,2n=20)、甘蓝(CC,2n=18)和黑芥(BB,2n=16)有共同的起源,其染色体基数为6,但它们的进化距离有明显的差异。Attia和Robbelen(1986)用双单倍体杂种的染色体配对和交叉频率说明,A与C两染色体组之间的关系比它们与B染色体组之间的关系要密切得多。但是,所观察到的减数分裂构型不仅是由进化中累积的染色体结构差异所致,而且还可能存在抑制部分同源染色体
Although three diploid ancestors of Brassica cultivars shared common origin with Brassica campestris (AA, 2n = 20), cabbage (CC, 2n = 18) and black mustard (BB, 2n = 16) Base 6, but their evolutionary distance there are significant differences. Attia and Robbelen (1986) showed that the relationship between the A and C genomes is much closer than they are to the B genome, using chromosome haplotypes and crossover frequencies of the double haploid hybrids. However, the meiosis pattern observed is not only due to the structural differences in chromosomes that have accumulated during evolution, but may also exist in which some homologous chromosomes are suppressed