Simple sequence repeat (SSR) markers for molecular diversity and heterozygosity analysis in maize (Zea mays L.) inbred lines

Abstract

An insight into the genetic diversity and relationships among the germplasm is important in any crop improve­ment programme. An effort was made to study the genetic diversity, polymomorphism and heterozygosity, among 10 maize inbreds using ten simple sequence repeats (SSR), spread across six maize chromosome viz, 1, 3, 4, 5, 6 and 8 during Kharif 2015. DNA from two week old young fresh healthy leaves was isolated using CTAB method and subjected to SSR marker analysis. A total of 14 alleles were detected across 4 polymorphic loci ranging from 2 (bnlg 1917) to 5 (bnlg 589) alleles per locus and an average of 3.50 allele. Mean value of polymorphic information content (PIC) was 0.49 which ranged from 0.26 (bnlg 1917) to 0.73 (bnlg 589). The mean value for expected heterozygosity (He) was 0.55 which varied from 0.32 (bnlg 1917) to 0.76 (bnlg 589), respectively. The Jaccard’s dis-similarity index was obtained ranged from 0.00 to 1.00.The Jaccard’s similarity coefficient divided maize inbred lines into five heterotic groups, where, Cluster I, III, IV and V contained one genotype each, and Cluster II- contained six genotypes. The study revealed that SSR markers are useful tool to explore the molecular diversity among the maize genotypes, as they are not influenced by the environment which can help breeders for selection of diverse parental lines which is useful for hybridization programme in heterosis breeding for maize yield improvement.