Genetic identification of 43 elite clonal accessions of Populus deltoides by SSR fingerprinting

Abstract

In this study, 43 elite clones of Populus deltoides were fingerprinted with ABI 3730 capillary electrophoresis by using six SSR primer pairs. Based on the fingerprinting profiles, 62 polymorphic bands were generated with a mean number of 10 alleles per locus, and allele numbers amplified by each primer in these clones ranged from 5 (NJFUP-poly10) to 16 (NJFUP-poly07). The power of discrimination values for these primer pairs ranged from 0.80 to 0.94, with an average value of 0.89. Among the six primer pairs, the most efficient primer pair for genetic discrimination of these elite clones was NJFUP-poly02, which could identify 22 of the 43 elite clones directly. In conclusion, all the 43 elite clones of P. deltoides could be discriminated unambiguously based on their genotypes at the six SSR loci. The combination of all six loci gave considerable reliability and accuracy for genetic identification of these clonal accessions. Subsequently, genetic relationship of these clones was plotted by the UPGMA clustering and principle component analysis. Results of both analyses indicated that clone “C7-1” had the largest genetic distance from the other clones, followed by clone “C51-1” and a subgroup comprising clone “C100-3” and “C62-3”. These clones are proposed to be possibly more affected by the inter-specific gene introgression.