Cultivar identification and genetic fingerprinting of guava (Psidium guajava) using microsatellite markers

Abstract

Guavas (Psidium guajava) are perennial fruit trees cultivated in tropical and subtropical areas of the world. In this study, we have characterized nine guava cultivars using 23 microsatellite markers. The number of alleles ranged from 3 to 12 with a mean of 6.39 alleles per locus. The polymorphic information content of the markers ranged from 0.340 to 0.900 with a mean of 0.749. The expected heterozygosity ranged from 0.392 to 0.961 with a mean of 0.824. The probability of identity ranged from 0.031 to 0.487 with a mean of 0.143. The total probability of identity was 2.73 × 10-22. Additionally, cluster analysis was done using both Wards minimum variance method and Neighbor Joining method. The clustering pattern generated from both the methodologies, distinctly grouped the pink flesh varieties and the white flesh varieties into two groups. Molecular barcodes have been developed for all the cultivars, which will increase the precision for their identification.