Scientific Journal of KubSAU

Modern domestic tomato hybrid should be competitive with tomato hybrids of foreign selection. To create a model of a future hybrid, a collection of modern tomato hybrids of domestic and foreign selection presented on the seed market was investigated. During the study, a modern method of genetic study of the genotype of tomato Real-Time PCR was used. As a result of the study, a model of a modern tomato hybrid with tolerance to powdery mildew of tomato was described. In the future, it is planned to carry out breeding work to create such a hybrid. In the course of studying the F1 collection of tomato hybrids, it was found that the modern model of a tomato hybrid should have the following characteristics: a semi-vegetative type of growth with closely spaced internodes, early and medium ripening, a simple type of inflorescence with 4–5 fruits if the average weight of fruit is more than 200 grams; with 6–7 fruits weighing up to 150 grams for collection by tassels. High strength of fruits with the absence of concentric and radial cracking, suitable for long-distance transportation, is required. In the genotype of the modern hybrid model, in addition to tomato powdery mildew resistance (Oidiun lycopersici), it is necessary to have a complex of resistance genes to such diseases as tobacco mosaic virus (Tomato mosaic tobamovirus), Fusarium oxysporum, verticillosis wilt of the tomato; ), brown spot of tomato (Cladosporium fulvum). It is also desirable the presence of a gene of resistance to the yellow leaf curl virus of tomato (Tomato yellow leaf curl virus) and the gall nematode (Meloidogyne incognita)

The article discusses the method of selection using markers in the selection of parent pairs for hybridization, in the selection process and in the subsequent evaluation of parent lines, used in linear and backcross selection of tomatoes. The work was performed on tomato hybrids that combine resistance genes to tomato mosaic virus (ToMV) or tobacco mosaic virus (TMV) in their genome. The research used seeds of foreign F1 tomato hybrids recommended by the manufacturer as resistant to the tobacco mosaic virus. Most of the tomato hybrids were Dutch selection, such leading firms as De Ruiter Seeds, Enza Zaden, Rijk Zwaan. The aim of the work was to test a system of hybridization probes designed to identify a gene for resistance to the tobacco mosaic virus. The study of the genotype of tomato plants was carried out in the laboratory of molecular diagnostics of plants , equipped with modern devices for PCR analysis on the basis of NIIOZG (Krymsk). Plant material was collected in different phases of plant vegetation. pre-numbered 1.5 ml test tubes (SSI-1200-00), plastic tablets, tweezers, and distilled water were used to collect plant samples. The collected samples were stored in a refrigerator until the plant DNA was isolated. During the study, collectible tomato samples were studied, including 8 F1 hybrids and 2 lines used as controls. According to the results of genetic analysis using the marker of the TMV resistance gene, it was found that all hybrids and one control line # 175/14 have a resistance gene in their genotype, and the analysis also showed the state of the gene – homozygous or heterozygous. The results of artificial infection confirmed the results obtained by PCR analysis. At the same time, using genetic research, it is possible to determine the exact state of the gene in the plant, which cannot be determined by methods of artificial infection, since no visual differences were found between plants with a heterozygous and homozygous state of the gene. The created marker and PCR analysis method can be recommended for wide application in the selection process of tomato culture. As a result of research, it was found that modern tomato hybrids have a gene for resistance to tobacco mosaic virus (TMV) in their genotype. This was determined by genetic analysis and confirmed by a test using artificial infection