Utility of isozyme markers for understanding genetic relatedness in Karanja (Derris indica L.,)

Abstract

In present study, we analyzed genetic diversity in Karanja (Derris indica) using isozyme markers of four enzymes namely, peroxidase, polyphenol oxidase, esterase, and superoxide dismutase, which collectively revealed 19 isoforms. Polyphenol oxidase exhibited highest number of isozymes (6), followed by peroxidase (5), superoxide dismutase (4), and esterase (4). Polyphenol oxidase exhibited the highest polymorphism (83.33%), while superoxide dismutase showed the lowest (50%). The isozyme polymorphic index, polymorphism information content (PIC) and marker index for isozyme markers was 2.0, 0.42 and 28.81 respectively. The highest polymorphic index and marker index was governed by polyphenol oxidase isozyme, while the esterase isozyme had the highest PIC value. Structure analysis and  principal coordinate analysis revealed two main clusters in the karanja germplasm. Additionally, we identified unique haplotypes of polyphenol oxidase, peroxidase and esterase isozymes that differentiate the genotypes NAUK-2, NAUK-5, NAUK-6, NAUK-14, NAUK-15, NAUK-16, NAUK-17, NAUK-21, NAUK-26, NAUK-28, and NAUK-30 from other karanja genotypes.