Soybean Yield as Affected by Biomass and Nitrogen Uptake of
Cereal Rye in Winter Cover Crop Rotations
Matías L. Ruffo, Donald G. Bullock and Germán
A. Bollero* , Department of Crop Sciences, Univ. of Illinois, 1102
S. Goodwin Avenue, Urbana IL 61801
The inclusion of cereal rye as winter cover crop following corn
has been suggested as a valuable nutrient management tool in the
typical corn–soybean rotation of the U.S. Midwest. However, little
information is available on the effects of rye winter cover crop
on the soybean crop. A study was conducted to quantify biomass
and nitrogen uptake of rye winter cover crop and to evaluate the
effect of rye winter cover crop on soybean yield.
The effects of four rotations (corn/soybean, hairy vetch–corn/rye–soybean,
rye–corn/rye–soybean, and hairy vetch + rye biculture–corn/rye–soybean)
on soil residual nitrogen content, rye biomass, soil residue cover,
soybean light interception, and grain yield were investigated
at Urbana and Brownstown, IL.
Rye nitrogen content was highly correlated with soil residual
nitrate content (r = 0.64, p < 0.0001). Rotations that only included
hairy vetch (Vicia villosa L.) reached maximum nitroogen content
at lower corn nitrogen rates compared with rotations with rye.
Soybean light interception at R1, R4, and R6 growth stages and
grain yield were not affected by the treatments. Rye winter cover
crops planted after corn appears to take up a significant proportion
of residual nitrate without affecting soybean grain yield, providing
an environmental service to the agroecosystem.