This project explores the effect fertiliser placement has on nutrient (and water) use efficiency given nutrient stratification, soil water availability and the root architecture of different crops. The project deploys a series of experiments designed to identify strategies that increase crop yield through increased phosphorus (P) uptake in central and southern NSW, Victoria and South Australia. Studies will be based on a combination of field experiments, and controlled environment studies that will be used to understand if and why certain combinations of P placement and soil moisture can enhance P fertiliser use efficiency for different crop types. Furthermore, the research will identify P application rates that can be used to enhance P uptake and crop yield. Computer simulation studies on soil water along with other data will help guide site and treatment selection.

The project has three components that address the following questions:

1. Does the dual placement of subsurface and surface P improve crop yield and/or P use efficiency over surface P placement only;
2. Do crop species differ in their response to subsurface P placement; and
3. How does water and root proliferation interact with subsurface P application and crop uptake of P.