Productivity and grain quality of various types of spring wheat depending on seeding rates and nutrition background on gray forest soil of the Pre-Kama Region of the Republic of Tatarstan

Abstract

The results of two–year (2018–2019) studies on the effect of various seeding rates and nutritional backgrounds on the yield and grain quality of two types of spring wheat – soft wheat and emmer wheat (spelt) – are considered. The agrochemical characteristic of the gray forest soil of the experimental plot is as follows: the humus content in the layer of 0–20 cm was 2.9–3.4 % (Tyurin method), mobile phosphorus amount was 176–241 mg, exchange potassium amount was 77–109 mg/kg of soil (Kirsanov method). The degree of saturation with bases was 85.2–87.7 %, the pH of the salt extract was 5.6–5.8. Agrometeorological conditions of 2018–2019, on the whole, met the requirements for early spring crop seeding, HTC (hydrothermal coefficient) was 0.85–1.2. Two levels of mineral nutrition were studied in the experiment (natural background, without fertilizing, NRK for the planned grain yield of 3 t/ha), four seeding rates against each nutrition background: 4, 5, 6 and 7 million germinating seeds per 1 ha. The seedling completeness in both types of wheat over an average of 2 years depended on the seeding rate, regardless of the background of nutrition. In soft wheat of Ulyanovskaya 105 variety, against a natural background, with an increase in the sowing rate from 4 to 7 million germinating seeds per ha, the seedling completeness decreased and amounted to from 82.5 to 76.3 %, in spelt, it was 84.7–78.6 %. On a fertilized ground it was, respectively, 83.4–78.0 and 84.1–77.6 %. Good preservation of plants in both types of wheat from the number of sown seeds and seedlings was noted when the sowing rate was reduced from 7 to 4 million: without fertilizer 82.6–88.5 % in common wheat and 83.5–90.4 % of spelt. On a fertilized ground it amounted, respectively, to 84.3–90.5 and 86.5–92.3 %. Changes in nutritional background by introducing calculated doses of mineral fertilizers for all options with seeding rates on average for 2018–2019 yielded an increase in soft wheat by 0.94 tons of grain per hectare and by 0.61 tons of spelt. The highest conversion efficiency of fertilizers at a sowing rate of 6 million in common wheat was 8.1 kg of grain per 1 kg of a.a., for spelt at a sowing rate of 4 million the figure was 5.6 kg per 1 kg of a.a.