Introduction. The use of molecular genetic methods in cotton plant breeding is an urgent task, which makes it possible to reduce the time for creating varieties with economically valuable traits. The emergence of new breeding samples of hybrid origin (PGSSH 1, PGSSH 7) with a long-day photoperiodic reaction, resistance to diseases and sucking pests, high quality fiber requires genetic research. Their comparison with breeding samples of semi-cultivated cotton (with green, red, gray fibers) makes

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... it possible to reveal differences and identify genetic markers that ensure the realization of the biological potential of plant development. The purpose of our study was to identify genetic markers of economically valuable traits of cotton for the creation of a new generation of breeding material for the northern regions of cultivation based on the molecular genetic polymorphism of the DNA (Deoxyribonucleic acid) of the studied samples. For research, we have selected two of the most effective methods for assessing genetic polymorphism using DNA markers. The first of these is the method of SSR markers -(English Simple Sequence Repeats), PCR (Polymerase chain reaction) with flanking primers to a short mini or microsatellite repeat. Another method using short random primers is RAPD analysis (Random Amplified Polymorphic DNA). Results and discussion. As a result of the study, it was found that SSR markers CM 129A-1, NAU-3299, SHIN-1409, BNL-299, TMB-0641, CGR-5238, CGR-5260, CGR-5249, CGR-5253 have the same indicators in all of the samples participating in the study, and only three markers (CM-43, CM-50, CGR-5264) show significant differences. Even in the varieties PGSSKh 1 and PGSSKh 7, which were obtained using the same breeding lines, these differences were found. As a result of the RAPD analysis using random primers (PR7, RA, Jeffreys, 33.15), 5 cotton genotypes were marked, for each of which a characteristic pattern was obtained -the RAPD spectrum. A total of 284 amplified markers were obtained for 5 cultivars. For several varieties, unique DNA fragments have been identified, which, most likely, can be considered species-specific, but in a certain combination can also be used as genus-specific markers. On average, for each primer, 17 marker DNA fragments were amplified for each cotton variety. The data obtained indicate that the most genetically distant variety is PGSSKh 7. The most closely related variety is PGSSKh1, which has a creamy fiber color and a variety with red fiber. These specimens are characterized by a short growing season of 110-115 days. As for the White and Green varieties, they are similar in fiber length and belong to the long-fiber group, and also have a longer growing season, ranging from 140 to 150 days. Variety PGSSH 7 is a new genetic donor of economically valuable traits. It is characterized by high yields, short growing periods and high quality fiber. Conclusions. Three microsatellite loci were found in the studied cotton varieties suitable for identification. The analyzed selection samples have both similar