Moein Javid

M.S. Level Student
Southern Illinois University Carbondale
Advised by Dr. Amir Sadeghpour

Assessing Fall Applied Phosphorus Sources and Wheat Cover Crop on the Following Soybean Performance

Growers often maintain soil test P (STP) using ammonium phosphate fertilizers, such as diammonium phosphate (DAP, 18-46-0) or monoammonium phosphate (MAP, 11-52-0) and employ fall application to avoid competition for time and wet field conditions, both prevalent in the spring. However, fall application of N with these P fertilizers presents a risk of N loss over the fallow period. One source that could minimize N loss during the fallow period is triple super phosphate (TSP; 0-46-0). This experiment evaluates wheat (Triticum aestivum L.) cover crop use of fall applied P sources and the following soybean (Glycine max L.) yield and yield component in rotation to evaluate response of soybean to wheat as a cover crop and P management in the fall. The trial had three P sources (DAP, MAP, and TSP) applied to supply 200 lb/acre P2O5 and a no-P control. These four treatments will be crossed with two levels of wheat cover crop (no cover and 2M seeds/acre) for a total of eight unique treatments (4 P source X 2 cover crop) replicated five times using a complete randomized block design. We will present the results on both wheat and soybean at the ISA conference.