The yield of amaranth seeds depending on the sowing depth

Goal. To establish the optimal depth of covering amaranth seeds of the Kharkivskyi 1 variety under conditions of sufficient moisture in the western forest-steppe of Ukraine. Methods. Analysis, synthesis, field research, mathematical processing. Results. It was established that the field germination was the highest under the sowing depth of 1 cm and 2 cm – 71% and 79% respectively. Increase in the sowing depth led to the field germination decrease. The density of plants before harvesting was also higher than under sowing at a depth of 1 cm and 2 cm: 27 and 28 plants/m2 respectively, which is more compared to the sowing depth of 5 cm (12-13 plants/m2) . The height of the plants under sowing on 2 cm depth was 211 cm, and deepening to 5 cm reduced the height to 181 cm. The analysis of the structural elements shows that the longest panicle (65 cm), the weight of seeds from a plant (14.4 g), the weight of 1000 seeds (0.84 g) were under sowing at a depth of 2 cm. The highest yield (3.88 t/ha) of amaranth grain was under 2 cm depth sowing. At a shallow sowing depth (1 cm), the yield decreased by 0.21 t/ha. Increasing the seed covering depth to 3 cm led to a decrease in grain yield to 3.47 t/ha. At a sowing depth of 4 cm, the yield decreased to 2.37 t/ha, or by 1.51 t/ha. Only 1.62 t/ha yield was formed under 5 cm depth sowing, which is less than 2.26 t/ha compared under 2 cm depth. Conclusions. High field germination of amaranth (74–79%) is achieved at a seed embedding depth of 1–2 cm. When the top layer of soil dries out, sowing at 3 cm is permissible. Embedding more than 3 cm, even with sufficient moisture, significantly reduces germination. The highest pre-harvest density (24–28 plants/m²) and height (208–211 cm) were observed at a depth of 1–3 cm. With increasing depth, the mass of seeds per plant and the mass of 1000 seeds decreased. The optimal depth is 2 cm, the permissible depth is 1–3 cm. Sowing deeper than 3 cm significantly reduces productivity and is impractical.