Planting Depth Study in SunflowersAgronomic Research and Field Trial Tuesdays
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The objective of this study was to determine the impact of different planting depths on sunflower yield.
The study was conducted in 2019 at two different locations in Ukraine, six plots were established where sunflower seed was planted at different depths, which were 1, 1.5, 2, 2.5, 3, and 3.5 inches (2.5, 3.8, 5.1, 6.4, 7.1 and 8.9 cm) deep. Individual plots were 8 rows wide and 50m long. The entire study was positioned in the field so that all treatments were planted into similar soil moisture conditions to avoid any influence from different soil conditions.
Sunflower seed planted at less than 2 inches resulted in poor emergence and yield.
Sunflower seed planted at 2 inches deep produced the optimum yield. Crop emergence was good and sunflower head size was more uniform.
Sunflower seed planted deeper than 3 inches resulted in reduced yield because of uneven crop emergence and subsequent head size and individual plants compensated.
The optimum planting depth for sunflower across the three sites was 2 inches (5.1 cm), which produced an average yield of 2.7 t/ha. When planting at 1 or 1.5 inches (2.5, and 3.8 cm) deep, a yield reduction of -63.6 and -12.5%, respectively, was measured. When planting too deep at 2.5, 3, and 3.5 inches (6.4, 7.1 and 8.9 cm), a yield reduction of -4.0 and -8.1 and -51.4%, respectively, was measured.
Planting depth is critical to achieving uniform emergence. Planting at very shallow depths resulted in significant yield loss because the seed was not planted at a depth where the soil moisture layer was consistent. Seed planted at depths below the optimum 2 inches (5.2 cm) also suffered significant yield loss because of uneven crop emergence.
Recommendations and Equipment Solutions:
The data generated from this study highlights the importance of planting depth. Since soil moisture levels are constantly changing and can vary between fields due to different soil types and landscapes, it is critical to check moisture levels before planting in order to determine the optimum planting depth. Also, it is important to consider the depth control systems on a planter. Auto downforce technology, such as Precision Planting DeltaForceTM, helps reduce variability in planting depth.
The lost revenue per hectare when planting sunflower at the wrong depths is displayed below.
Price of sunflower – $400/t
Mark Moore, Agricultural Development Manager for Europe and the Middle East, AGCO Corporation. Connect with Mark on LinkedIN.