The peculiarities of the formation of yield and sowing qualities of soft winter wheat seeds depending on the preceding crop, sowing date and fertilisers

Abstract

Purpose. To identify the features of the formation of yield and sowing qualities of soft winter wheat seeds depending on a pre-crop, sowing date and different doses of nitrogen fertilizer in the conditions of the central part of the Forest-Steppe of Ukraine. Methods. The study was conducted from 2021/22 to 2023/24 at the V. M. Remeslo Myronivka Institute of Wheat of the NAAS. The influence of different nitrogen fertilizer (UAN-32) norms [25, 50 and 75 kg/ha of active substance (a.s.)], sowing dates (5 and 15 October) and precrops (sunflower and soybean) on the yield and sowing qualities of three soft winter wheat varieties (‘MIP Assol’, ‘Estafeta Myronivska’ and ‘MIP Dniprianka’) was established. The sowing qualities of soft winter wheat seeds were determined according to generally accepted methods in different variants of the experiment. Results. It was determined that the conditions in a given year had a significant influence on yield, 1,000-seed weight, conditioned seed yield and sprouting activity. The indicators of germination energy and laboratory seed germination remained relatively stable under different growing conditions. In drier growing conditions in 2021/22, significantly lower values of yield (3.81 t/ha) and 1,000-seed weight (42.6 g), as well as significantly higher seed sprouting activity (87%), were observed compared to in 2022/23 and 2023/24. The highest conditioned seed yield (75.9%) was obtained in 2023/24. The highest average yield values (4.79–5.04 t/ha), 1,000-seed weight values (43.5–44.9 g) and conditioned seed yield values (72.9–75.2%) were obtained after sowing soybeans. Higher yields (4.07–5.38 t/ha) and 1,000-seed weights (43.9–45.8 g) were found when sowing on 5 October. No significant effect of sowing dates on the yield of conditioned seeds was found. It was determined that fertilising the plants with UAN-32 at an application rate of 75 kg/ha a.s. contributed to significantly higher yields and maximum 1,000-seed weights (43.1–47.4 g) and conditioned seed yields (74.5–81.6%) compared to other nutritional standards. No significant effects of sowing dates, precrops or different fertilising rates on sprouting activity, germination energy or laboratory seed germination were found. Over the years, stable direct relationships (r = 0.70–0.92) were found between yield and 1,000-seed weight, as well as between yield and conditioned seed yield. Conclusions. To obtain higher yields, it is worth sowing soft winter wheat varieties on 5 October after a soybean precrop with UAN-32 nutrition at a rate of 75 kg/ha a.s.