Degree and nature of heterosis effects in corn lines by grain quality parameters

Aim. Widespread use of corn hybrids, which are of key importance for the food security in Ukraine, is one of the most successful examples of the heterosis phenomenon use. In order to recommend new and high-quality corn hybrids for production, it is necessary to assess the inheritance degree and heterosis effects for protein, starch and oil contents as well as for yield. Results and Discussion. To achieve the goal, we used the classic field techniques and methods of qualification examination of plant varieties for suitability for distribution in Ukraine. The protein, starch and oil contents in grain were determined on a InfratecTM 1241 Grain Analyzer (FOSS); the heterosis effects were calculated by D. S. Omarov’s methods. As a result of tester crosses, 65 experimental corn hybrids were obtained. Inbred lines VK13, VK69, AE801 and AE392 (carriers of the wx and ae mutations of endosperm structure, respectively) were the female forms. Inbred lines СО255, АК159, АК157, G255, FV243 and KhLG1203 were used as male components for the first time to obtain hybrids with high grain quality parameters. From the 2020−2021 studies, we found that, in terms of grain quality, the grain starch content-driven selection of parental pairs was the most rational approach, as the influence of parental forms on this trait consistently exceeded 50% across the study years. Conclusion. Hybrids VK13×UKhK678 and VK13×UKhK686 were noticeable for consistently high manifestation the heterosis effects for several parameters. As to the starch content in grain, superdominance of a parental form with stronger expression of the trait was recorded in hybrids VK13×UKhK678, VK13×UKhK686, VK19×FV243, and AE801×VK32; as to the oil content in grain, VК13×UKhК678, VК13×UKhК686, VК13×VК37, АЕ392×СО255, АЕ392×KhLG1203, and АЕ392×АК157 were distinguished. Inbred corn lines that should be used as parents of heterotic corn hybrids (KhLG1203, CO255, AK159 and AK157) were singled out.