The study is aimed to determine the influence of No-till technology and mineral nutrition backgrounds on the potential soil infestation with weed seeds. The field experiment was carried out on ordinary chernozem of Stavropol Krai in a crop rotation of peas–winter wheat–sunflower–corn starting in 2012. The crops were cultivated according to the recommended technology with and without tillage (No-till) on two nutrition backgrounds: with and without application of mineral fertilizers. Two crop rotations after, the 0–20 cm soil layer on the field with the recommended technology exhibits significantly higher number of weed seeds than that in the No-till option (by 15 672–18 051 seeds/m2, 32.9–37.4%). Application of mineral fertilizers significantly increases the values of this indicator, by 30.9–40.3%. Recommended technology decreases the proportion of weed seeds from 26.9–27.0% in the 0–5 cm layer to 21.3–22.0% in the 15–20 cm layer regardless of fertilization levels. In the No-till variant, the main part of weed seeds (57.5–60.3%) is in the upper layer (0–5 cm), while in the underlying layers their share sharply decreases to 6.9–8.0% (in the soil layer of 15–20 cm). Regardless of the cultivation technology, weed seeds of 10 families have been detected in the soil: with the recommended technology, 13 species, and with No-till, 14 species. In all variants of the experiment, the seeds of early and late spring species predominated, including common purslane, mat amaranth, red-root amaranth, annual ragweed, and black bindweed.
Dridiger et al. (Wed,) studied this question.