Analysis of genetic diversity among Indian garlic (Allium sativum L.) genotypes using SSR markers and morphological traits

Genetic diversity of seventeen garlic genotypes wwas evaluated using morphological characters and molecular markers. Twenty-three morphological characters related to the foliage and bulb traits of garlic were assessed and categorized into quantitative and qualitative parameters. Analysis on the basis of 16 SSR primers was used, out of which 7 produced clear polymorphic bands in garlic genotypes and conveniently distinguished all the genotypes under study. SSR markers used were capable of detecting 42 alleles with an average of 2.63 alleles per locus. The number of alleles per locus ranged from 1 to 7 and the allelic polymorphism information content (PIC) value ranged from 0.14 to 0.45 with an average of 0.26. Genetic divergence was calculated using the Pearson coefficient in which the genetic similarity varied from 0.04 to 1.0 and on the basis of morphological traits ranged from 1.65 to 6.12 with an average of 3.6 which was higher than molecular markers. Morphological traits are less valid to evaluate genetic diversity because these traits depend on the environmental and climatic factors like day length and temperature, as they are adapted for distinct climatic regions. The study revealed considerable amount of genetic variability among garlic genotypes and identified a correlation between molecular markers and morphological traits. The present study also indicates that though the microsatellite markers are fast and high throughput for DNA fingerprinting there is a need for more markers to be developed to assess genetic diversity.