Molecular characterization of Kinnow mutants

Abstract

The present experiment was conducted during 2016-18 at Division of Fruits and Horticultural Technology, ICARIARI, New Delhi. A total of 40 Kinnow mutants and 1 wild type were selected for molecular characterization and diversity analyses. Thirty-four SSR markers were screened for polymorphism, of which only 2 were found informative. Twelve alleles were detected among 2 SSRs with an average of 6 alleles per locus and the highest number of alleles (7) was recorded in SSR locus AMB2. The average diversity indices of SSR, viz. allele frequency, gene diversity, observed heterozygosity and PIC were 0.415, 0.672, 0.415 and 0.611 respectively. The N-J tree was constructed based on the 2 SSRs data which clustered the mutants into 2 major groups. Subsequently, clusters were simplified into 6 clades which distinguished gamma-irradiated and EMS derived mutants and results were reconfirmed through principal coordinate analysis (PCoA). First three axes of PCoA contributed 80.88% of the cumulative variation among the Kinnow mutants. The analysis of molecular variance (AMOVA) explained 42% variation among the populations, 48 and 10% variation within and among the individuals respectively. The present investigation genetically characterized the Kinnow mutants and deciphered the genetic diversity among them. Thus, the variability generated through induced mutagenesis could be used as valuable genetic material for Kinnow improvement.