Database Research Summaries2018 Soybean planting date and tillage interactions for variable rate seeding across management zones
Research Focus
The focus of this project is to determine if a planting date and tillage environment should be taken into consideration when determining planting populations in variable rate planting.
Objectives
- Determine if the yields and economics of variable rate soybean planting can be improved by writing prescriptions based on planting date and tillage.
- Evaluate the effect of the planting date, tillage, and population on the time to canopy closure.
- Determine whether yield components are affected differently based on planting date and tillage as populations change.
Results
- The early planting date increased yields on average 3.1 to 4.8 Bu/ac. The earlier planting dates resulted in reaching 75% emergence 10 to 19 days sooner than the late planting date. The V1 growth stage was reached 7 to 16 days sooner than the late planting. The sooner V1 is reached the more opportunity for a higher total number of nodes on a plant. The early planting dates increased canopy closure 4.6 to 15 days sooner than the late planting dates.
- Vertical tillage increased yields in both the early and late planting date averaging 2.0 Bu/ac across the site year locations. The early planting date averaged 4.1 Bu/ac increase across the locations in 2017 and 2018.
- The best economical treatment across the site year locations was early planting with vertical tillage and the lower average population (VRA B). In comparing early planting vertical tillage with VRA B to planting late in no-till with VRA B, yields increased an average of 6.7 Bu/ac across the site year locations. If planting late; vertical tillage and higher populations were important and increased yields an average of 3.2 Bu/ac compared to no-till with lower populations.
- Population did not consistently influence tillage. However, in the late planting dates, the no-till treatments did have higher yields with VRA A prescription but it was not always economical.
Importance
- This study may help soybean farmers to improve profitability by fine tuning their seeding rates by planting date and tillage system across management zones.
- This could also help farmers without variable rate determine if planting date and tillage should be taken into consideration when determining the average planting population on a field-by-field base.
For more information about this research project, please visit the National Soybean Checkoff Research Database.
Funded in part by the soybean checkoff.
