Genetic Diversity and Structure of Maize Accessions of North Western Himalayas Based on Morphological and Molecular Markers

Genetic diversity among 48 maize genotypes was determined using 11 morphological traits, 4 biochemical traits and 29 SSR primers. To assess the genetic diversity, data on morphological traits were recorded during the year 2013–2014 using standard maize descriptors. Eleven morphological traits observed across the 48 maize genotypes showed wide variation and grouped various test genotypes into two clusters. Based on the mean performance of genotypes, LM-19-07 and HKI-1348 were found superior for grain yield/plant, cob length, cob girth, kernel row/ear among all the genotypes. Protein content of LM-02-08 was the highest among all the genotypes. CML193 was found superior for iron and zinc content. Carotenoid content of LM-19-07 was higher as compared to checks. At molecular level, 29 SSR primers amplified 96 polymorphic alleles with an average of 2.16 alleles per primer. Size of amplified alleles ranged from 50 to 500 bp. Mean polymorphic information content was 0.43 showing high level of SSR polymorphism. Cluster analysis based on SSR data differentiated 48 maize genotypes into two major clusters. Bayesian model-based structure analysis assigned genotypes into two clusters and also showed the extent of admixture within individuals. Clustering pattern of maize genotypes based on SSR marker profiles was different from that of morphometric traits. Based on the pooled analysis at morphological, biochemical and molecular level, genotype LM-19-07 was found superior as well as most distant among all the accessions under study. So the genotype LM-19-07 could be used in future breeding programmes for genetic improvement in maize.