Reliable Propagation of Persian Walnut Varieties Using SSR Marker-based True-to-type Validation

Simple sequence repeat (SSR) markers were used to authenticate ramets of 11 Persian walnut (Juglans regia L.) varieties. All varieties and 28 of their ramets (n = 39) were genotyped with 17 SSR markers. The genetic profiles revealed two off-types: the ramets Serr 4 (S4) and Vina 1 (V1). SSR fingerprints individuating 11 walnut varieties were possible using 13 polymorphic SSRs that could be used in the future to identify clones of these varieties. Except for ‘Chandler’, each cultivar could be distinguished using a combination of two SSR loci. This result emphasizes the efficacy of the SSR markers in true-to-type validation of walnut orchards.