Yield and Sowing Qualities of Winter Bread Wheat Seeds Depending on the Preceding Crops and Sowing Dates in the Forest-Steppe of Ukraine

Abstract

Wheat is one of the most important crops in the world due to its wide geographical adaptation and nutritional value. The use of high-quality seeds of the best varieties being adapted to local growing conditions is an important requirement for increasing wheat yields. The purpose of this research was to establish the influence of preceding crops and sowing dates on yield and seed sowing quality of winter bread wheat varieties. On average, maximum yield capacity in 2016–2018 was obtained in the variety Trudivnytsia myronivska (7.41 t/ha) when sowing on 15 September after green manure, the minimum yield was in the variety MIP Kniazhna (4.03 t/ha) when sowing on 15 October after soybean as preceding crop. Shifting the sowing dates to later ones led to decrease in yield capacity by 0.97 and 0.62 t/ha after the preceding crops green manure and soybean, respectively. After the preceding crop soybean, the maximum yield (5.77 t/ha) was formed by the variety MIP Valensiia when sowing on 25 September. By ANOVA it was found that the level of wheat yield was the most significantly affected by hydrothermal conditions of the year (63%), the interaction “preceding crop  conditions of the year” (12%) and preceding crop (11%). It was revealed that an increase in weight of 1000 seeds in the varieties on average was 3.9 g after the preceding crop green manure in comparison with the preceding crop soybean. There was a slight effect of preceding crops and sowing dates on seed vigor and laboratory germination. These rates were slightly higher for early and optimal sowing dates after green manure as compared with the soybean. Thus, it was confirmed that in the Right-Bank Forest-Steppe green manure is the best preceding crop for seed production, especially for growing pre-basic seeds, while 15 and 25 September are the best sowing dates. For the preceding crop soybean, when sowing on 25 September and 05 October, the yield of wheat varieties was the highest in comparison with sowing on 15 October. Locations of winter wheat seed crops after the best preceding crops in crop rotation and optimal sowing dates will promote the most efficient using of climatic and anthropogenic factors, increase grain yield per area unit, and improve seed sowing quality.