Seeding System Configuration Effects on Sunflower Seedling Emergence and Yield under No-Tillage

No-tillage farming can improve crop productivity and the reliability of cropping compared with conventional tillage. The effects of three different seeding system configurations on surface residue handling, sunflower emergence and stand establishment, yield, and gross income were investigated over three cropping seasons. The seeding system configurations comprised of (1) turbo coulter blade, (2) notched disc row cleaner before turbo coulter blade, and (3) no residue handling unit installed in front of a double-disc opener. For all three seeding system configurations, crop residue cover on sown rows (after seeding) was greater than the minimum recommended value of 30% for no-tillage. Residue cover was best with the notched disc row cleaner in front of the turbo coulter blade compared to the other two seeding systems. Furthermore, the notched disc row cleaner in front of the turbo coulter blade produced the highest plant emergence counts and the most uniform stand establishment. Sunflower yield and gross income were highest with the notched disc row cleaner in front of the turbo coulter blade (3.16 Mg·ha−1 and 902 USD·ha−1) compared to when only the turbo coulter blade (2.38 Mg·ha−1 and 680 USD·ha−1) or no residue handling unit (1.69 Mg·ha−1 and 482 USD·ha−1) was used.