Influence of winter wheat varieties and precursors on soil fertility, grain yield and quality in Stavropol territory

Abstract

Research was conducted on the basis of JSC "Agrohleboprodukt" branch "Agrokevsalinsky" Ipatovsky district of Stavropol territory in 2017-2019 to determine the feasibility of sowing varieties of soft winter wheat (Triticum aestivum L.) on sunflower and chickpeas with No-till technology. The production experience was carried out on an area of 3000 m2. The scheme of the experiment is 2-factors: varieties (factor A) – Zustrich (St.), Bagira, Bagrat; precursors (factor B) – sunflower and chickpeas. 
 The climate of the zone is arid. The average annual temperature is 10.3°С. The average annual precipitation is 36.1 mm. The soil of the farm is dark chestnut carbonate heavy loam. Indicators of water resistance (for sunflower and chickpeas was 49.5 – 49.9 % and 66.7 – 68.2 % respectively) and the coefficient of structure (1.9 – 2.1 and 2.1 – 2.3 respectively) of dark chestnut soil before sowing varieties of winter wheat had optimal values for all predecessors. On average, the soil density for the growing season for sunflower is 1.28 g/cm3, chickpeas – 1.20 g/cm3. For varieties from sowing to the full ripeness phase, the soil density increases by 4.8 % and 2.5 % respectively. On average, the reserve of productive moisture for the growing season for sunflower is 64.7 g/cm3, chickpeas – 76.2 g/cm3. The greatest moisture availability is observed when sowing sunflower and chickpeas in the Bagrat variety – 66.2 mm and 78.8 mm respectively.
 The content of humus in the soils of the farm is 2.62 – 2.69 %, exchange potassium – 362.5 – 400.5 mg/kg; mobile phosphorus – 32.7 – 37.0 mg/kg; nitrogen – 13.4 – 13.9 mg/kg. In terms of humus content during the growing period, Bagrat varieties have the highest indicators for sunflower and legume precursors (2.62 % and 2.70 %), as well as for exchange potassium, mobile phosphorus and nitrogen (365.7 – 403.0 mg/kg; 33.2 – 37.4 mg/kg; 14.4 – 14.9 mg/kg).
 The average yield for sunflower and chickpea varieties is 4.44 t/ha and 4.67 t/ha respectively. Bagrat variety proved to be the most productive for both predecessors (for sunflower – 4.72 t/ha, for chickpeas – 5.00 t/ha) with high grain quality indicators (the amount of raw gluten – 27.1 %, nature – 726.4 g/l, vitreous – 86.3 %). The constructed trend models reflected a very high relationship between the predecessors, soil fertility indicators and winter wheat yield (r=1.0).