Formation of winter wheat productivity elements and their relation to sowing quality in the central part of the right-bank forest-steppe of Ukraine

Abstract

This article presents the research results on "Zolotokolosa" winter wheat variety sowing quality and its impact on field emergence, tillering coefficient, and productive tiller formation. The studies showed that it is quite challenging to adjust the seeder for accurate sowing rate, and the deviation over the three-year research period reached up to 5.1 %. The accuracy of seed burial depth with disc drills was relatively low, fluctuating around an average of 4.24, 4.6, and 4.3 cm compared to the planned depth of 4.5 cm. However, significant variation was observed within designated plots during the vegetation period of 2018–2019 (3.4–5.2 cm), 2019–2020 (3.5–5.9 cm), and 2020–2021 (3.4–5.3 cm). Field emergence depended significantly on weather conditions and soil moisture, being favorable in 2018 and 2019 with rates of 95.3 % and 94.1 %, respectively. However, the summer-autumn drought negatively affected field emergence in 2020, resulting in a lower rate of 85.5 % compared to previous years. The depth of tillering node burial during the research period ranged from 1.85 to 1.9 cm. More significant fluctuations were observed within designated plots during the vegetation period, ranging from 1.5 to 2.2 cm. The correlation coefficient between seed burial depth and tillering node burial depth was positive (r = 0.554, r = 0.095, r = 0.237). The coefficient of productive tillering showed slight variation over the years of research. During the vegetation period of 2018–2019, it averaged 1.56, while in the subsequent years it was 1.60 and 1.54, respectively. The highest number of productive tillers, exceeding the sowing rate of 5.5 million seeds per hectare, was formed during the 2019–2020 vegetation period, with an average of 717.6 tillers/m2 . However, there was significant variation in this value within the designated plots, ranging from 605 to 869 tillers/m2 or 84.3 % to 121.1 % of the average density. In the 2018–2019 vegetation period, the average number of productive tillers was 709.4/m2 , with fluctuations within the designated plots ranging from 588 to 869 tillers/m2 or 82.1 % to 122.5 % of the average density. The lowest number of productive stalks of wheat was recorded in 2020–2021, which can be attributed to a relatively dry autumn vegetation period. On average, there were 646.8 tillers/m2 . The density fluctuated the most within the designated plots that year, ranging from 499 to 863 tillers/m2 or 77.1 % to 133.4 % of the average density. The research methods employed included field observation, laboratory analysis, comparative analysis, data synthesis, and mathematical-statistical analysis. Key words: winter wheat, sowing quality, field emergence, tillering coefficient, productive tillering.