Real-time sensing of crops for management intervention - application of thermal and hyper spectral technologies Summary This project will deliver validated indices derived from remote sensing that can spatially measure and map canopy-level crop nitrogen (N) status within rainfed wheat systems. Remote sensing (spectral and thermal) combined with crop models can provide maps showing chronic and acute water stress areas that can guide N management strategies within the context of potential for response to targeted N inputs. Spatially varying nitrogen (N) inputs to better match crop demand can increase profits by 5 to 20% and perhaps more as the price of N continues to increase. This information can help growers redistribute or reduce N inputs resulting in lower input costs or increased yields. More efficient use of N could also reduce environmental impacts from run off, denitrification and volatilisation. Background In-season N application is being used to supplement or replace pre-planting N application. New sensor technology is commercially available, such as active optical sensors and satellite imagery with spectral bands that may provide growers information on the relative or even absolute amounts of N required by the crops. Implications The project outcomes will support in-season N applications to reduce or eliminate pre-season N applications. This change in agronomy could potentially lead to an overall reduction in the use of fertilizer or at least provide for more even canopy N across a paddock, and could optimize the production. Objectives In-season N application is being used to supplement or replace pre-planting N application. New sensor technology is commercially available, such as active optical sensors and satellite imagery with spectral bands that may provide growers information on the relative or even absolute amounts of N required by the crops. Research Paddock scale measurements of plant N and crop biomass is collected along with sensor measurements throughout the growing season. The research focuses on ways to relate the sensor measurements to plant N and biomass during the stem-elongation phase when growers need information on the crop N requirements.