Enhancing the Profitability of Wheat-Soybean Double Cropping: What Have We Learned?

By Jessica Rutkoski

Advancements in technology and crop genetics continue to push the boundaries of what farmers can achieve within a single growing season. This is especially true for wheat-soybean double cropping. Successfully producing two crops in the same growing season requires each crop to be more efficient to maintain yield with fewer days of sunlight and less-than-ideal growing conditions.  

On the wheat side of the double-crop equation, varieties must be high-yielding and early-maturing while also demonstrating strong scab resistance, standability and test weight. The University of Illinois wheat breeding program makes hundreds of new genetic combinations and evaluates thousands of candidate varieties each year to identify those that meet these criteria.  

With funding from the Illinois Soybean Checkoff program, we have been leveraging our skills and testing capabilities to help farmers make more informed wheat cultivar selection decisions. Each year, we test about 100 commercial wheat varieties for yield performance across six locations in Illinois as part of the Official State Variety Testing Program. At two of these locations, we evaluate when each variety begins jointing and when it matures.

The timing of jointing in early spring matters because earlier jointing puts wheat at greater risk for freeze damage. The timing of maturity is critical because it determines when the double crop soybeans can be planted. For each day of later wheat maturity, farmers lose about one-half bushel of double-crop soybean yield due to delayed soybean planting. Ideally, we want to see normal or late jointing and early to medium-early maturity combined with excellent grain yield, scab resistance and test weight.