Potential options for measuring mid season rice crop nitrogen

To maximise yield potential and economic returns while minimising risk it is important to measure nitrogen (N) uptake at panicle initiation (PI) so rice crop growth and N status can be assessed to allow accurate mid-season N topdressing decisions.

Farmers in Australia physically sample their crops at PI, record fresh weight and send sub samples to a laboratory for N analysis using near- infrared (NIR) spectroscopy. They are then provided with a N topdressing recommendation for each field. Many farmers find sampling their rice crops in water arduous, so options are being explored that don’t require physical sampling.

In this poster we investigate the GreenSeeker and Yara N-testerTM to determine their ability to measure rice N content and biomass at PI. 

Tina Dunn, NSW Department of Primary Industries, 2014