芥蓝—菜薹种间三倍体回交子代染色体数鉴定及单体异附加系的选育

Chromosome Number Identification and Generation of Monosomic Alien Addition Line in the Triploid Interspecies Hybrid of Flowering Chinese Cabbage-Chinese Kale

为创造CC染色体组附加A染色体组的单体异附加系,以芥蓝—菜薹种间三倍体(CCA)为材料,采用人工杂交、形态和细胞学鉴定及核型分析等方法,比较了芥蓝—菜薹种间三倍体与其亲本芥蓝(CC)正、反交的结实性,分析了杂交子代的染色体数及频率分布,并对筛选出的单体异附加系进行了系统研究。结果表明:CCA×CC和CC×CCA的结籽率分别为0.28%和0.63%;在鉴定的88个CC×CCA的子代中,全部为2n=18的整倍体植株;在鉴定的156个CCA×CC的子代中,(2n+1)～(2n+9)等各类非整倍体均有存在,其中附加1条染色体的1个、附加2条染色体的16个;形态学标记鉴定和核型分析显示附加1条染色体的那个子代植株为单体异附加系CC+A9;在减数分裂终变期,单体异附加系CC+A9的A9染色体常与一对C组的染色体发生局部联会,两者间存在着部分同源关系;单体异附加系CC+A9的n+1雌、雄配子均有一定传递率,分别为18.75%和9.82%;单体异附加系CC+A9自交获得了1株双体异附加系。

In order to generate monosomic alien addition line of C-genome added the chromosome derived from A-genome,the triploid interspecies hybrid （CCA） and its parent Chinese kale （Brassica alboglabra Bailey） and Flowering Chinese cabbage （Brassica campestris L.var.utilis Tsen et Lee） were used as the basic materials,by means of artificial hybridization,morphological and cytological examination and karyotype analysis,the seed setting of CCA × CC and CC × CCA,the chromosome number of their hybrids and the monosomic alien addition line of CC genome added a A-chromosome were identified.The main results showed as follows：① The seed setting of CCA × CC and CC × CCA was 0.28% and 0.63% respectively;② All of 88 progeny plants identified in CC × CCA were euploid（2n=CC=18）;③ Aneuploids with different number extra chromosomes were existed in the identified 156 progeny plants of CCA × CC,in which one 2n ＋ 1 plant and sixteen 2n ＋ 2 plants were obtained;④ The monosomic alien addition line CC ＋ A9 was preliminary determined by morphological marker identification and karyotype analysis for the 2n ＋ 1 plant;⑤ Meiotic observation for the addition line CC ＋ A9 showed A9 chromosome having partial homology with a pair of C-chromosomes;⑥ The alien chromosome A9 of the monosomic addition line CC ＋ A9 could be transmitted by male and female gametes with a percentage of 9.82% and 18.75%,respectively.