Assessment of Quality Protein Maize (QPM) inbreds for genetic diversity using morphological characters and simple sequence repeats markers

An investigation was performed to characterize 25 indigenous Quality Protein Maize (QPM) inbred lines for several morphological traits to study the level of genetic diversity present in the inbreds by utilizing morphological characters and microsatellite markers. On the basis of morphological traits by adopting D2 statistics and Tocher’s method of clustering all the studied inbred lines were clustered into seven clusters and by using molecular markers, based on Jaccard’s similarity coefficient, these were clustered into five clusters. The inbred lines MTCA 1, MTCA 2, MTCA 8, MTCA 6, and MTCA 11, were grouped together, indicating that these inbred lines of maize were closely related to one another in terms of morphological and molecular characterization. Out of the total primers studied, five were observed with more than 0.5 PIC value. SSR primers utilized for the molecular characterization of inbred lines with the mean PIC value of 0.543, were quite informative. A total of 41 alleles were observed with an allele count ranging from 2-5 per locus. The 13 SSR primer pairs used for estimation yielded a total of four unique alleles, with a mean of 0.31 unique alleles per primer. The similarity coefficient estimates for pairs of individuals varied from 0.000 to 1.00. Among the pair-wise combinations of entries evaluated, the magnitude of the similarity coefficient between MTCA 11 and MTCA 10 (1.00) was the highest. However, the molecular data and the cluster diagram based on morphological data were at odds which may be due to the enormous genome size of a cross-pollinated crop like maize.