Obtaining and evaluating breeding material for the creation of F1 hybrids of Chinese cabbage (B. rapa ssp. pekinensis) with resistance to stress factors

Relevance and purpose of the study. Chinese cabbage is a vegetable crop with a high content of vitamins and low calorie content, valued for its ability to receive several crops per year and high productivity. Recently, there has been a reduction in the supply of the vegetable to Russia. There are less than 70 varieties and hybrids of the crop in the State Register of Selection Achievements, many of them are susceptible to the most important diseases. It is necessary to meet consumer demand with new commercial hybrids with resistance to stressors. The aim of the study was to evaluate and obtain genotypes with a set of valuable economic traits, including resistance to clubroot, powdery mildew, and early bolting. Materials and methods. The Chinese cabbage lines of various degrees of inbred and DH, as well as hybrid combinations from crossing these lines, were used as plant material. The lines were obtained in 2019-2020, the breeding material for them was selected on the ground infected with clubroot and with tolerance to tip burn of heads. To achieve the goal, the following methods were applied: plants cultivation; DNA isolation (CTAB method); PCR analysis; electrophoresis and visualization of results; productivity assessment and dispersion analysis; obtaining doubled haploids in culture of isolated microspores in vitro, assessment of resistance/susceptibility to powdery mildew. Results. 2 genotypes with high productivity and alignment in turnover summer-autumn 2022 and a genotype exceeding 3 standards in head weight in turnover spring-summer 2022 were recommended; as a result of molecular genotyping, 41 lines were differentiated according to the club-root resistance gene CRb; DH plants for 4 genotypes with resistance to early bolting were obtained, their responsiveness to embryogenesis was studied; 18 lines were evaluated for resistance to powdery mildew, 7 genotypes with resistance to the disease were identified.