Considerations for Planter Downforce and Seeding Rate to Maximize Emergence and Yield in Singulated Versus Hill-Drop Planted Cotton

Obtaining early uniform crop emergence is highly dependent on correct selection of planter parameters as well as crop variety selection based on prevailing field conditions. A study was conducted during the 2018 growing season to evaluate crop emergence and yield as affected by seeding rate and planter downforce under singulated and hill-drop seeding configurations. Two cotton cultivars differing in seed size and vigor (a small seeded low vigor variety and a large seeded high vigor variety) were planted using singulated and hill-drop cotton plates at a seed depth of 1 inch. Three different seeding rates (20,000, 28,000, and 43,500 seeds/ac) were used along with two planter downforce treatments of zero and 200 lbs. of applied force on the individual row-units. The study was planted using a 4-row Monosem Vacuum Planter equipped with a manual downforce control system under strip-till conditions. Field data collection consisted of stand counts at one and three weeks after planting (WAP) to evaluate crop emergence, and yield data during harvest. Results suggested that the large seeded high vigor cultivar had higher mean emergence (54-81%) at 3 WAP than the mean crop emergence (38-60%) for the small seeded low vigor cultivar irrespective of the seeding rate and downforce treatments. Statistical analysis did not show any significant differences (p>0.05) in crop emergence values between the singulated and hill-drop treatments in both cultivars. Higher mean yields (1510-1880 lbs/ac) were recorded for the large seeded high vigor cultivar than the mean yields (1160-1680 lbs/ac) for the small seeded low vigor cultivar. This study emphasized the careful consideration of planting parameters such as seeding rate and planter setup along with proper selection of cultivar and assessing existing in-field conditions to maximize crop emergence and yield potential in cotton.