Analysis of genetic diversity in pomegranate using SRAP (Sequence-related amplified polymorphism) markers

Abstract

Sequence-related amplified polymorphism (SRAP) was used to assess the genetic diversity of 114 pomegranate accessions sourced from all over the world and maintained in the field gene bank at ICAR-Indian Institute of Horticultural Research, Hesaraghatta, Bangalore. Totally 10 SRAP combinations were used for the study. Genetic parameters such as effective alleles (Ne), Nei genetic diversity (H), Shannon index (I), and polymorphic information content (PIC) were calculated based on molecular data. The number of alleles per locus ranged from 1.66 to 4.00 with an average of 2.03. The average polymorphic information content (PIC) value was 0.24. The expected heterozygosity varied from 0.215 to 0.445 with an average of 0.306. Cluster analysis was performed using R software. All the 114 accessions were grouped into four major clusters. There was no clear grouping based on origin. The analysis of molecular variance (AMOVA) indicated insignificant genetic variation (p=0.31) between pomegranate accessions from different geographical locations. Overall genetic variation among the population groups was low, while 99% of variation was due to within group differences. These results confirmed that SRAP markers could be a powerful and an effective marker system for determining the genetic diversity and population genetic structure of the pomegranate.