Dennis Baker, Extension Agriculture and Natural Resources Agent
The objective of this research was to determine whether soybean yields will be affected when decreasing the seeding rates from the recommended rate of 160,000 to 175,000 seeds per acre.
| Test Site: | County Farm | Herbicide: | |
| County: | Darke | PRE | 26 oz/A Roundup Ultra Max |
| Nearest Town: | Greenville | 1.4 oz/A Scepter | |
| Soil Type: | Miami silt loam and Eldean loam | POST (July 10) | 26 oz/A Roundup Ultra Max |
| Drainage: | Subsurface | Variety: | Ebberts 1351RR |
| Tillage: | No-till | Planting Rate: | See Methods |
| Previous Crop: | Corn | Planting Date: | May 1, 2001 |
| Soil Test: | pH 7.5, P 24ppm, K 160ppm | Row Spacing: | 30 inch |
| Fertilizer: | 0-46-0 (100 lb/A) and 0-0-60 | Harvest Date: | October 22, 2001 |
| (125 lb/A) broadcast |
Soybeans were planted using a Buffalo slot planter with Kinze brush-type seed meter units. Three treatments of different planting rates were replicated four times in a randomized complete block with each treatment strip of twelve 30-inch rows approximately 2/3 acre in size. One stand count was taken approximately three weeks after emergence in each of the four replications of each treatment to verify differences in seeding rates. Plants were counted in 30-inch row lengths in areas of rows that were uniform in emergence. Entire strips were harvested for yield results. Harvest moisture was determined using a field moisture tester. A weigh wagon was used to determine weight of grain harvested in each plot. Yields were adjusted to 13% moisture. Results indicate attempted seeding rates, plant populations, and yields of each test.
| Table 1. Plant Population and Yield for Seeding Rate Treatments. | ||
| Treatment | Stand Count | Yield |
| (seeds/A) | (plants/A) | (bu/A) |
| 75,000 | 71,148 | 65.8 |
| 125,000 | 113,256 | 66.1 |
| 175,000 | 166,980 | 65.5 |
| LSD (0.05) | NS | |
| F | < 1 | |
| CV (%) | 1.7 | |
There were no significant differences in the yields when comparing three different seeding rates of soybeans planted in 30-inch rows. The most recent recommendation from Ohio State University on seeding rates in 30-inch rows is nine seeds per foot of row, or approximately 157,000 seeds per acre. This was an exceptionally good year for growing soybeans in our area. It would be interesting to see if lower number of plants in wide rows could yield as well as higher populations under hotter and/or dryer conditions.
For further information, contact:
Dennis Baker
Ohio State University Extension, Darke County
700 Wayne St.
Greenville, OH 45331
937-548-5215
baker.5@osu.edu