Steve Prochaska, Extension Agriculture and Natural Resources Agent
To evaluate the effect of row width and modified relay intercropping on wheat yield.
Modified Relay Intercropping is a system in which soybeans are planted into standing wheat around the time period of wheat pollination. Previous plot work over the last six years has resulted in soybean yields of 30 bushels per acre and wheat of 73 bushels per acre. (Yield averages over all treatments.)
| Test Site: | Ohio State University | Fertilizer: | 32-81-120 lbs. actual |
| Unger Farm | NPK/A applied 9/24/99 | ||
| County: | Crawford | Topdressed 33 gal. 28% | |
| Soil Types: | Pewamo silty clay loam | (99 lb N)/A on 3/24/00 | |
| Blount silt loam | Seeding Rates: | Wheat 120 lb./A | |
| Tillage: | Chisel plow and field cultivator | Soybean 211,000 seeds/A | |
| Previous Crop: | Soybeans | Planting Date: | October 7, 1999 |
| Row Spacings: | 7.5 inches and 15 inches | Harvest Date: | July 5, 2000 |
| Varieties: | Wheat - I9824 Soybean Pioneer 93B35 |
||
A completely randomized design (seven replications) in small plots (5 x 50 feet) was used. Treatments were 15-inch row-spaced soybeans intercropped into wheat in 15-inch rows alongside 7.5- and 15-inch row wheat with no soybeans. Wheat and soybeans were planted with a three-point hitch-mounted tool-bar planter equipped with Sunflower openers. Soybeans were interseeded on June 2. Wheat harvest was done on July 5 with a small plot combine.
| Treatments | Yield (bu/A) |
| 7.5-inch row wheat | 72.3 b |
| 15-inch row wheat | 70.8 b |
| 15-inch row wheat interseeded | 62.0 a |
| LSD (0.05) = 3.4 bu/A
F value 24.6, CV 4.0% Means followed by the same letter are not statistically different. |
|
Wheat yields at the two different row widths without modified relay intercropped soybeans were not significantly different from each other. However, wheat modified relay intercropped with soybeans yielded significantly less at a comparable wheat row width. This yield difference of about 12% is consistent with work done by other researchers (McCoy, S.M, T. J. Vyn, and T. D. West, Effect of Acrylic Polymer Seed Coating on the Feasibility of Relay Intercropping in Indiana, Purdue University) working with wide-row wheat in an intercrop system.
The difference in wheat yield may not be as large in narrower rows. Also, weather, as it affects wheat disease development and soil moisture, may impact wheat yield in a modified relay intercropping system.
For additional information, contact:
Steve Prochaska, Agriculture and Natural Resources Agent
Ohio State University Extension, Crawford County
117 East Mansfield Street
Bucyrus, OH 44820
419-562-8731
prochaska.1@osu.edu