Molecular genetic analysis of potato genotypes for late blight resistance

Abstract

Increasing crop yields and enhancing their adaptation to changing growing conditions are among the key strategies for ensuring food security. Potato is one of the most important food crops worldwide and is cultivated on all continents. Plant breeders play a crucial role in ensuring sustainable potato production by developing new resistant varieties with increased yield per hectare. Since the 1990s, genetics has played an increasingly important role in plant breeding through the introduction of DNA markers as indirect selection tools and for the assessment of genetic diversity. Today, genomics-based plant breeding approaches, such as marker-assisted selection (MAS) and genomic selection (GS), accelerate the breeding process for many major crops. The aim of this study was to identify genes conferring late blight resistance in 30 promising potato hybrids using DNA markers. Laboratory analyses for late blight resistance were conducted at the Laboratory of Molecular Genetic Research of Agricultural Plants at the Vladikavkaz Scientific Center of the Russian Academy of Sciences. The breeding material was preliminarily evaluated under field conditions in accordance with the recommendations for potato breeding programs. Genomic DNA was extracted from potato leaves during the flowering period using the CTAB method. For molecular genetic analysis of late blight resistance, the following R-gene molecular markers were used: R1–1250, R3a-1380, and R3b-378. The molecular genetic analysis revealed the presence of all three markers R1–1250, R3a-1380, and R3b-378. They were identified in five different potato hybrids. These hybrids included: 3375–1 (Tiras × Breeze), 3403–2 (Arizona × Fritella), 3341–2 (Innovator × Mirage), 3352–1 (Kolette × Mirage), and 3352–4 (Kolette × Mirage). The presence of all three genes indicates a high degree of late blight resistance. Thus, the identification of potato genotypes using molecular markers facilitates the acceleration of the breeding process for developming new resistant potato varieties.