Evaluation of the degree of dominance and heterosis effect of table watermelon according to the main economic characteristics

. Heterotic selection is now widely used in crop production. The superiority of heterotic hybrids over varieties in many respects has long been known. However, the widespread use of heterosis in melon growing is hampered by the high cost of seed material, due to the lack of lines with male sterility. The aim of this work was to evaluate heterotic hybrids of watermelon obtained on the basis of a line with male sterility isolated at the Bykovskaya Experimental Station.Materials and methods. The studies were carried out in 2020 and 2021. at the Bykovskaya melon breeding experimental station - a branch of the FGBNU FNTSO. The object of research is heterosis hybrids of watermelon. The heterosis hybrid of watermelon Barkhan was used as a standard. Classical breeding methods were used in the work: incubation and hybridization.Research results. The assessment of watermelon hybrids according to the main economic characteristics revealed the best combinations in comparison with the standard. According to the content of dry matter, four hybrids of watermelon stood out, the excess over the standard ranged from 0.6 to 1.9%. The indicator of the average weight of the fetus in one LIR hybrid was at the level of the standard and amounted to 6.5 kg. The remaining hybrids exceeded the Barkhan standard by 1.2-4.0 kg. The average yield of the studied hybrids ranged from 19.0 to 22.5 t/ha. The calculation of such indicators as the degree of dominance, the effects of true and hypothetical heterosis made it possible to identify three combinations with high rates.Conclusion. Thus, it was found that the yield in heterotic hybrids of watermelon is inherited according to the principle of overdominance. Inheritance of traits dry matter content and average fruit weight ranges from minus overdominance to overdominance in various combinations. According to the complex of economically valuable traits, three combinations of table watermelon were distinguished: LKn, LMr and LFT.