MPfN - Sugar cane systems
The issue
Sugarcane has a large production potential and nitrogen (N) remains a key nutrient that drives productivity and profitability. However, crop N use efficiency remains generally below 40-60% of applied fertiliser. N loss pathways include nitrate (NO3-) leaching and run-off, and denitrification. Clearly improvements in N use efficiency are needed
In addition the location of many Australian sugarcane farms near coastal areas necessitates the development and adoption of sustainable production practices.
Objectives
- To determine the extent of subsoil (deep) N reserves in northern NSW cane paddocks to allow refined N fertiliser application rates.
- To develop new tools (Mid Inra Red/Near Infra Red) to predict Potentially Mineralisable N (PMN) in soil.
- To assess the potential of polymer coated (controlled release) urea as a way to better match N supply with crop demand in two-year cane crops, by;
- Determine yield and N uptake response curves between urea and controlled release urea (5 rates)
Outputs and/or outcome
- Adjustment of N fertiliser application to some NSW sugarcane farms with significant stores of N fertiliser (up to 300 units of N). These stores are made up of mineral N and PMN prior to planting or the ratoon crop.
- Rapid test developed based on mid infra-red spectroscopy for NSW sugarcane soils that can reasonably predict PMN.
- Results suggested minimal benefits of slow release (polymer) coated urea (either 90 day or 270 day release) in the dry years that the field trials were conducted. Better climate forecasting (particularly in-crop rainfall predictions) would enable farmers to make decisions on N application.
- UAV based multispectral imaging used to assisted research trials on assessing crop N uptake throughout the growing season.
Partners (or collaborators)
Southern Cross u\University
Sunshine Sugar
Sugar Research Australia
Australia Department of Agriculture, water and the environment
