Yield and quality of winter wheat depending on sowing dates in the Southern Steppe of Ukraine

Abstract

Changing climatic conditions necessitate continued research to refine sowing dates for new winter wheat varieties and determine the level of their influence on productivity indicators, taking into account the specific weather conditions of the year. Therefore, the study of sowing dates, especially for innovative varieties with intensive initial growth, remains a relevant issue. This research aimed to determine and adapt to the conditions of the Southern Steppe of Ukraine the optimal and permissible sowing dates for new winter wheat varieties to achieve the highest possible level of realisation of their genetic potential in terms of yield and grain quality. Field experiments were conducted in 2021-2023 under the conditions of the Odesa Region. The main method used in the experiment was field research, which was supplemented by analytical studies, measurements, calculations, and observations. The harvest was recorded using a continuous threshing method with a SAMPO selection combine. It was established that the highest grain yield of winter wheat over the three-year study was achieved with sowing on 5 October. In 2021-2022, the average yield was 3.60 t/ha, while in 2022/2023, it increased to 3.90 t/ha. The highest yields were recorded for the following winter wheat varieties sown on 5 October (average for 2021-2022): Dovira Odeska – 4.03 t/ha, Katrusia Odeska – 5.16 t/ha, Pokrovska – 4.48 t/ha, Hospodarka Odeska – 4.28 t/ha, and Udacha Odeska – 4.08 t/ha (2022/2023). It was found that the grain quality of winter cereals largely depends on the year’s weather conditions, variety, and sowing dates. The best results for these indicators were obtained with sowing on 5 October. However, for all winter wheat varieties, there was a tendency towards an increase in protein and gluten content in the grain when sown on 15 October. Thus, the practical value of this research lies in identifying the adaptability of new-generation winter wheat varieties to unfavourable growing conditions, realising their potential genetic yield, and determining the optimal and permissible sowing dates in the soil and climatic conditions of the Southern Steppe of Ukraine