Formation of productivity of maize hybrids of different ripening groups in the Forest-Steppe region

Abstract

The relevance of the study is determined by the necessity of scientifically substantiating the rational ratio of maize hybrids of different ripening groups to ensure the realisation of the genetic potential in forming pre-harvest grain moisture at the level of 18-22%. Therefore, the purpose of the study is to identify the most adapted and plastic ripening groups considering biological features and to identify stable hybrids based on economic efficiency through the calculation of the hybrid’s productivity efficiency index. The method of plot division was used to conduct field research in accordance with the requirements of the research methodology. The results revealed that maize hybrids of different ripening groups react differently to temperature conditions, especially during the interphase period – 3-5 leaves. Maize hybrids with FAO (ripening group of the hybrid) 180-250, having a flint grain subtype, are characterised by faster linear plant growth due to higher cold resistance, making them suitable for early sowing when the soil temperature is 6-80C. Hybrids with FAO 300 and above, with a dent grain subtype, exhibit slower initial plant growth and are more thermophilic. Therefore, it is advisable to plant them after the soil has been thoroughly warmed to 8-100C. Studies have established that the highest grain yield was obtained from mid-late maturity maize hybrids (FAO 401-500) – 10.04-10.17 t/ha, with a maximum level of 14.89 t/ha in 2017. However, considering the dynamics of productivity levels over the years, the most plastic hybrids, i.e., those with the smallest difference in yield between years, are phenotypes with FAO 201-300. It was determined that early and mid-early ripening group hybrids had lower pre-harvest grain moisture – 0.6-23.9% compared to 28.7-2.7% in mid-ripening and mid-late ripening groups. This resulted in a higher productivity efficiency index for these hybrids. The materials of the study contain results for further research on optimising the use of maize hybrids with different FAO numbers and are of practical significance for farms of various ownership forms