Genetic Evaluation of Sweetpotato Accessions Introduced to the Central European Area

Abstract

The objectives of the study were to investigate the genetic relationships of sweetpotato [ Ipomoea batatas (L.) Lam] genotypes, acquired from different origins and to evaluate the genetic relations among them,using eight SSR markers. A high level of polymorphism was found, with an average of 7.5 alleles per SSR locus. High average values of Shannon’s informatio n index (0.864) and expected heterozygosity (0.739) revealed high level of genetic diversity of the Sweetpotato genotypes. Favorable applicability and informativity of selected set of SSR markers was confirmed by high global polymorphic information content (0.690) and low probability of genotype identity ( 1.4×10 - 8 ). The overall fixation index was negative ( - 0.562), reflecting excess of heterozygosity, due to negative assortative selection as a consequence of vegetative propagation of sweetpotato. Estimation of Rst based on AMOVA shows 23% of molecular variance; the first two coordinates of PCoA cumulatively explaining 62.33% of genetic variability. The assignment of individual genotypes into three genetic groups is highly concordant with the PCoA and Bayesia n approach in Structure analysis. Our results suggest that selection and breeding can also improve genetic potential and increase genetic uniformity in sweetpotato. Evaluation of genetic background and relationships among and within genotypes provided base line data for introduction, management, production and conservation of sweetpotato germplasm, regarding its favorable consumer acceptance in Central Europe. Keywords: Genetic structure, Genotypes, Polymorphism, SSR markers, Sweetpotato.