Genotyping of Strawberriy Varieties (Fragaria L.) by Pathogen Resistance Loci

The study was conducted with the purpose of molecular marking of strawberry varieties for resistance alleles to powdery mildew, anthracnose and red stele root rot. The biological objects of the study were 54 strawberry varieties (F. x ananassa) from the genetic collection of the I. V. Michurin Federal Scientific Center. Genomic DNA extraction was performed according to a modified CTAB protocol. Strawberry pathogen resistance alleles were identified using classical PCR (08 To-f – powdery mildew resistance, Rca2 – anthracnose resistance, Rpf1 – red stele root rot resistance) and high-resolution melting curve analysis (anthracnose resistance loci FaRCa1 and FaRcg1). The 08 To-f powdery mildew resistance locus was identified in 11.1 % of the analyzed strawberry varieties. The FaRCa1, Rca2 and FaRcg1 anthracnose resistance loci were present in 40.7 %, 12.9 % and 35.2 % of the analyzed samples, respectively. The Rpf1 red stele root rot resistance gene was identified in 1.8 % of the analyzed strawberry varieties. At least one of the 5 studied resistance loci is present in 74.1 % genotypes (among Russian varieties – in 78.6 % samples, among foreign varieties – in 69.2 % samples). Combinations of 5 and 4 resistance alleles in one genotype were not identified. The combination of three resistance alleles was identified in the Borovitskaya (FaRCa1, Rca2 and FaRcg1) and Sudarushka (Rca2, FaRcg1 and 08 To-f) varieties. The combination of two resistance alleles was detected in 22.2 % of strawberry varieties: Zenit, Neznakomka, Urozhaynaya CGL, Flora, Salsa and Vicoda (FaRCa1+FaRcg1), Aprica (FaRCa1+Rca2), Ostara (FaRCa1+08 To-f), Bylinnaya (08 To-f+Rpf1), Florence and Malwina (08 To-f+Rca2). The indicated varieties are promising complex genetic sources of pathogen resistance alleles and are recommended for inclusion in the breeding to improve the strawberry assortment.