Genetic Characterization of Drought-Tolerant Maize Genotypes Based on SSR Markers

Abstract

Using 20 pairs of SSR primers situated on each chromosome of the maize genetic makeup, 27 drought-tolerant maize genotypes obtained from the Germplasm Unit of the International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria, were examined for diversity. The samples' genomic DNA (gDNA) was extracted using the CTAB procedure specified by CIMMYT (2005). All 20 pairs of SSR markers used in this investigation were extremely polymorphic, resulting in 122 repeatable and polymorphic bands that were scored with an average of 12.20 alleles. Each primer yielded a main allele frequency of no more than 0.5. The average major allele frequency for the 10 primers was 0.3036. With an average of 0.8334, all markers had gene diversity values greater than 0.6. Similar to this, the Polymorphic Information Content (PIC) values had an average of 0.8164 and varied from 0.9051 (primer umc1042) to 0.6639 (Umc1669). Since primer umc1042 best identified this variability, the frequency of the main alleles generated by each primer points to the presence of significant molecular genetic variation across the samples under study. This occurrence is further supported by the gene diversity (GD) and polymorphism information content (PIC) values of the primers. Therefore, it can be inferred that the primers are all appropriate for genotyping genetic diversity. Due to their different genetic relationships, varieties IWD C2 SYN F2 and SAMMAZ 52 have the most diversified genotypes and can be utilised as parent materials in a maize breeding programme.