Analysis of Genetic Diversity in Maize(Zeamays L.)Varieties Using Simple Sequence Repeat(SSR)Markers

Abstract

A total of 41 alleles were detected among the tested varieties using 10 Simple Sequence Repeat (SSR) loci distributed on 9 chromosomes of maize.The molecular size of bands obtained from amplification of SSR products ranged from 91 to 288 bp. Alleles ranged from one in umc1653 to ten in bnlg1189 loci. The values of heterozygosity for each locus varied from 0.46 for umc1641 and umc1069 loci to 0.88 for bnlg1189 locus with a mean of 0.55. The polymorphic information content (PIC) values for the SSR loci ranged from 0.17 to 0.85, with an average of 0.44. The highest PIC values were observed in primers bnlg1017 (0.85) and umc1038 (0.79) and the lowest PIC values was observed in primer umc1946 (0.17).The study revealed that, the lowest genetic distance was (0.2410) between varieties IPA 5011 (lane 6) and Sarah (lane 8), while, the highest genetic distance was (0.7853) between varieties DKC 6120 (lane 15) and Manlcet (lane 19). The genetic similarity values ranging from (0.2147 to 0.7590) depending upon the genetic distance values that ranging from (0.2410 to 0.7853), which indicate the larger diversity with percentage of (24 to 78%) among the tested varieties. Analysis of the obtained results from genetic distances and Neighbor-joining dendrogram (unrooted tree) revealed that, the 20 tested maize varieties can be grouped into two major groups: one small cluster A containing 4 varieties and a large cluster B containing 16 varieties. The results obtained in this study may assist maize cultivation and in maize breeding programes.