Genetic Characterisation and Diversity Assessment of Potato Genotypes Using SSR Markers

Abstract

Information on diversity of genetic materials is vital for choosing parents in a breeding program. The objective of the study was to determine the pattern and level of genetic diversity among the selected 20 tetraploid potato genotypes using 16 SSR markers to identify suitable parents for breeding purposes. The microsatellites showed considerable variation among genotypes and sixty four alleles were amplified by the 16 primer pairs. The number of polymorphic alleles per locus ranged from 2 to 8 with an average of 3.9. The highest number of null alleles was observed was six for genotype Nakpot1. The overall size of the amplified product varied from 48 bp (marker STI0023) to 309 bp (marker STM5121). PIC values ranged from 0.0948 to 0.7832, with an average of 0.4307 per locus. Heterozygosity values ranged from 0.0997 to 0.805 with an average of 0.466919. Significant positive linear correlations were observed between PIC values and number of alleles (r = 0.905); and heterozygosity and number of alleles (r = 0.8659) at p < 0.001. Cluster analysis separated the genotypes into three different groups. The genetic distance between clones ranged from 1 to 5.7. Cruza had the highest genetic distance while the shortest genetic distance was observed between 396026.103 and 396034.104. The microsatellites used in this study provided useful information regarding the variability of the tested genotypes and their selection for breeding purposes.