SSR markers are useful tools in wheat varietal purity and genetic diversity assessment

Assessing genetic similarity and purity degree among wheat cultivars is important in breeding programmes and SSR markers have all the features that make them suitable for this purpose. The aim of this study was to assess the varietal purity and genetic diversity among wheat cultivars grown in Romania using 22 SSR markers and to choose the most informative markers. The 40 samples included in the study consisted of seeds from certified and non-certified wheat cultivars, and from other related species. To establish that varietal purity is maintained, seeds from 14 certified wheat cultivars were analysed from two harvesting campaigns (years 2019 and 2020) and seeds of four of them were also compared with the authors' seeds. The most polymorphic SSR marker was Xwmc596 (seven alleles), followed by Xwmc603 and Xwmc474 (six); Xgwm71, Xbarc347 and Xbarc074 (five); Xgwm469, DuPw004, Xgwm155 and Xbarc184 (four); Xwmc418, Xbarc170, Xwmc533, DuPw167, DuPw115, Xgwm413 and Xgwm372 (three); and DuPw217, DuPw205, Xgwm003 and Xgwm095 (two). SSR marker Xgwm052 showed low polymorphism (one). No contamination of the varieties was observed in these harvesting campaigns since all SSRs markers showed high similarity in the certified wheat cultivars harvest analysis; genetic diversity between genotypes was also observed.