BACKGROUND: The sign of the number of rows of grains on the cob is one of the key to improving the productivity of corn. The effects of the genes that control this trait have been poorly studied. The search for sources and donors of this trait is relevant for hybrid breeding. MATERIALS AND METHODS: The studies were carried out on 16 lines (S3-6) with different inbredness and varying the number of rows of grains on the cob from 18 to 36, the exotic race CUZCO characterized by large grains. Hybridization and crop recording were carried out in the field conditions of the foothill zone of the Kabardino-Balkarian Republic RESULTS: Conducted by ranking the putative sources of genes td1, ct2, fea2, fea3, fea4 by phenotype. Other promising sources and donors for the multirow trait without pronounced fasciation of the cob have been identified. An experimental hybrid was obtained between the MP-20 population and the high-starch, large-grain race CUZCO. Analysis of the structure of the cob of the F1 hybrid showed that the trait of multi-row cob from the maternal form and coarse grain from the paternal form in the hybrid phenotype manifests itself as an incomplete dominance type with the formation of the number of rows and the weight of 1000 grains according to the intermediate type. The yield potential of the experimental simple hybrid was no less than 12.2 tons per 1 hectare with a harvest grain moisture content of 37% and an FAO ripeness group of no less than 600. CONCLUSIONS: The collection of multirow maize lines serves as a valuable source of genes that control important quantitative traits and can be involved in the breeding of hybrid maize for its improvement.