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

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.