Impact of Planter Type, Planting Speed, and Tillage on Stand Uniformity and Yield of Corn

Planter type, maintenance, and operation play an important role in uniform stand establishment in corn (Zea mays L.). Research was conducted to determine if planter type affects corn yield by altering plant spacing and emergence variability and to determine if planting speed and tillage influence these effects. This experiment was performed at two locations in south-central Ontario during a 2-yr period. Treatments were established with conventional tillage (CT) and no-tillage (NT) as main plots, three planter types (vacuum meter, finger-pickup, and air seeder) with differing mechanisms including varied seed-singulating mechanisms as subplots, and two planting speeds of 7.2 and 11.3 km per hour (kph) as sub-subplots. Planter type affected stand uniformity with mean standard deviation (SD) of within-row plant spacing of 7.9,10.3, and 19.9 cm for vacuum meter, finger pickup, and air seeder, respectively. A higher SD was observed in NT for finger pickup and air seeder but remained the same for vacuum meter. For all planters, SD increased at faster planting speeds. The number of days required to achieve 50% emergence was similar between the vacuum meter and finger pickup but was greater for the air seeder, especially when planting speed was increased and NT was used. Final plant population was unaffected by planter and planting speed treatments. Overall, grain yields decreased 35.9 kg ha -1 for each centimeter increase in within-row plant spacing SD and 292.8 kg ha -1 per day of delay in emergence. Results suggest that grower's attention to corn planter mechanisms and maintenance is more critical under a NT system or when operating speeds are increased.