甜玉米L-11与糯玉米L-70的染色体核型分析

Chromosome Karyotype analysis of sweet corn L-11 and waxy corn L-70

摘要: 采用常规根尖压片法对甜玉米和糯玉米的染色体标本做核型分析.结果表明: 甜玉米（L-11株系）和糯玉米（L-70株系）的染色体数均为2n＝20,两者均为二倍体.甜玉米核型公式为2n＝2x＝20＝2M﹢12m﹢6sm(2Sat),染色体相对长度系数组成为2L﹢4M2﹢12M1﹢2S,按照Stebbins标准核型分类属于2B核型,不对称系数AS.K%＝59.66%.糯玉米核型公式为2n＝2x＝20＝2M﹢8m(2Sat)﹢10sm，染色体相对长度系数组成为2L﹢8M2﹢6M1﹢4S，分类属于2A核型,不对称系数AS.K%＝60.41%.说明甜玉米（L-11株系）的进化程度较高.

Abstract: The chromosomal karyotypes of sweet corn and waxy corn were analyzed using the conventional root-tip squashing method. The results showed that both sweet corn line L-11 and waxy corn line L-70 were diploids and had chromosome numbers of 2n= 20. The sweet corn had a karyotype formula of 2n＝2x＝20＝2M﹢12m﹢6sm(2Sat), the chromosome relative length index of 2L﹢4M2﹢12M1﹢2S, and the asymmetry coefficient of AS.K%＝60.41%, belonging to the 2B type according to Stebbins standard karyotype classification. While the waxy corn had a karyotype formula of 2n＝2x＝20＝2M﹢8m(2Sat)﹢10sm, the chromosome relative length index of 2L﹢4M2﹢12M1﹢2S, and the asymmetry coefficient of AS.K%＝59.66%, belonging to the 2A type. Conclusion: the evolution degree of sweet corn line L-11 is relatively high.