两种不同基因型辣椒的核型比较

Karyotype Comparison of Two Genotypes in Capsicum annuum L.

对长形椒(Capsicum annuumL.var.longumSendt)和朝天椒(Caoicum annuumL.var.conoidesIrish)2种不同基因型辣椒作了根尖细胞染色体分析,并从细胞学角度讨论了两者的亲缘关系。结果表明,长型椒的核型公式为2n=2x=24=20m+2 sm+2T,属二倍体的2B型,各染色体均未发现有随体,最长与最短染色体长度比为2.40,臂比>2的染色体比为0.17,不对称系数为60.22%。朝天椒的核型公式为2n=2x=24=18m+4 sm+2T,属二倍体的2B型,各染色体均未发现有随体,最长与最短染色体长度比为2.05,臂比>2的染色体比为0.08,不对称系数为60.28%。核型分析结果同时还表明,长形椒和朝天椒在染色体水平上具有较近的亲缘关系,这为辣椒遗传育种和品质改良提供了细胞学依据。

The root tip cell chromosomes of two kinds of different genotype Capsicum annuum L. which were var. longum Sendt and var. conoides Irish were analysised in this paper, and the relationships between them in the angle of cytology was discussed too. The results showed that the karyotype formula of var. longum Sendt was 2n = 2x = 20m ＋ 2sm ＋ 2T, belonged to 2B type, there was no SATS; the chromosome length ratio was 2.40, the chromosome ratio of the ratio 〉 2 was 0. 17,the index of asymmetry was 60. 22%. The karotype formula of var. conoides Irish was 2n = 2x = 24 = 18m ＋ 4sm ＋ 2T, belonged to 2B type too, there was no SATS too; the chromosome length ratio was 2. 05; the chromosome ratio of the arm ratio 〉 2 was 0.08, the index of symmetry was 60. 28%. The analysis of karyotype also indicated that var. longum Sendt and var. conoides Irish have near relationship on the level of chromosome,which provided the cytology basis of Capsicum annuum L. genetic breeding and quality improving.