Jim Lopshire, Agriculture and Natural Resources Extension Agent
To evaluate the effect of seeding rate on yield for conventional soybeans planted in 15-inch rows.
| Cooperator: | Jay Schmidt | Herbicide: | |
| County: | Paulding | PRE: 4/26/02 | 2,4-D (12 oz/acre) |
| Nearest Town: | Payne | Detail (2 pints/acre) | |
| Soil Type: | Hoytville | Sencor (6 oz/acre) | |
| Drainage: | Systematic | POST: | None |
| Tillage: | No-Till | Planter: | Kinze 2600 |
| Previous Crop: | Corn | Row Spacing: | 15-inch |
| Fertilizer: | None Applied | Planting Rate: | See Treatments |
| Variety: | LG 3201 | Planting Date: | June 4, 2002 |
| Harvest Date: | October 5, 2002 |
Three population rates were used to determine the effect of seeding rate on yield. The planting rates selected were 161,350, 182,400, and 219,540 seeds per acre using a Kinze 2600 no-till planter. Treatment rates were based on settings listed in the planter manual. Treatments were replicated four times in a non-randomized complete block. The harvest plots were one acre in size measuring 60 feet wide by 726 feet long. Each strip was weighed using calibrated portable scales, and the yield was adjusted to 13% grain moisture level.
Harvest population was determined by counting the soybean plants in 1/1,000 acre on two corresponding adjacent rows for each individual treatment.
Table 1. Plant Population, Moisture, and Yield for Seeding Rate Treatments.a
| Planting Population | Harvest Population | Moisture | Yield |
| (seeds/A) | (plants/A) | % | (bu/A) |
| 161,350 | 111,250a | 13.5 | 50.0 |
| 182,400 | 119,750a | 13.0 | 50.8 |
| 219,450 | 150,500b | 13.1 | 51.7 |
| LSD (0.05) | 18,671 | NS | NS |
| F - test | 16.2 | <1 | 1.0 |
| a Means followed by a different letter in the same column are significantly different. | |||
The harvest population was less than 70% of the planting population for the three treatments. Populations were not significantly different between two of the three treatment means. There was no significant difference in soybean averages for yield or moisture.
Data from this first-year study suggests that the soybean populations did not produce a significant yield increase among the three populations. Seed cost per acre ranged from $16.74 per acre for the lowest plant setting of 161,350 plants per acre to $22.77 for the highest population setting of 219,450 plants per acre. This is a savings $6.03 per acre.
The author would like to thank Jay Schmidt and his father Dick Schmidt for their cooperation in this study.
For further information, contact:
Jim Lopshire
Ohio State University Extension, Paulding County
503 Fairground Drive
Paulding, OH 45879
419-399-8225
jlopshire@ag.osu.edu