Estimation of genetic diversity in fieldpea (Pisum sativum L.) based on analysis of hyper-variable regions of the genome

The genetic diversity present in the widely adapted Indian fieldpea varieties, many of which are from exotic background, has rarely been studied with DNA based markers. Forty-five microsatellite markers were used to assess the genetic variation within twenty four elite pea cultivars grown extensively in India. Out of total 45 markers, 39 markers amplified a total of 55 alleles with an average of 1.4 alleles per marker. Maximum diversity was recorded between cultivars KPMR 44-1 and Ambika. The average similarity coefficient value was found to be 0.84. Cluster analysis based on Dice similarity coefficient using UPGMA, grouped tall type and dwarf type varieties into two different clusters based upon their pedigree. Very low polymorphism within the studied genotypes indicates an urgent need to include diverse parents in fieldpea breeding programmes. The present study also generated valuable information about the comparative usefulness of genic and genomic microsatellite markers. Genomic microsatellite markers showed higher degree of polymorphism compared to the genic microsatellite markers.