Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40 Page 41 Page 42 Page 43 Page 44 Page 45 Page 46 Page 47 Page 48 Page 49 Page 50 Page 51 Page 52 Page 53 Page 54 Page 55 Page 56 Page 57 Page 58 Page 59 Page 60 Page 61 Page 62 Page 63 Page 64 Page 65 Page 66 Page 67 Page 68 Page 69 Page 70 Page 71 Page 72 Page 73 Page 74 Page 75 Page 7650 IREC Farmers' Newsletter No. 195 ­ – Rice R&D 2016 this instrument across seasons and varieties can be achieved. micaSense RedEdge Recently the compact micaSense RedEdge camera was released, which scans the red edge as well as the traditional red, blue, green and NIR wavelengths, and it is small enough to be mounted on a drone. One season’s data has been collected with the micaSense RedEdge camera and the relationship between NDVI (normalised difference vegetation index) and PI nitrogen uptake is shown in Figure 2a. The normal problem with NDVI when used for measuring rice PI nitrogen uptake, as shown by the figure, is that as the PI nitrogen uptake goes above 90 to 100 kg N/ha the NDVI saturates and no difference in the NDVI reading occurs. When the red edge wavelength is used with a different indice, NRENDVI = ((NIR–red edge)/(NIR+red edge) the relationship with PI nitrogen uptake is greatly improved (Figure 2b). A second season’s data is required to see how accurately the instrument performs across years. How accurate does the prediction need to be? A significant question in this research is how accurate does the prediction need to be? Especially when 70% of growers currently are not using the NIR tissue test. There are also sampling errors that can occur with the current physical sampling for the NIR tissue test and a remotely sensed option has the advantage of showing the spatial variability that is present across the field. Ideally the remotely sensed option would be accurate enough that no physical sampling would be required, but if this cannot be achieved will farmers and agronomists accept a remotely sensed test that still requires a reduced level of sampling? Where to now? In the 2016–17 rice season the Worldview 3, micaSense RedEdge and the new Parrot Sequoia camera will all be tested across a range of nitrogen experiments and in several commercial fields. Once analysis of that data is completed the sensing technology that provides the best prediction accuracy of PI nitrogen uptake at an affordable price will be identified. The opportunity for development of a semi-commercial system for determining nitrogen uptake of rice at PI will be assessed after results from the coming seasons experiments have been collated. The project team will also monitor and test new technology as it becomes available as technology is this area is evolving rapidly. RIRDC Project PRJ-009772 Moving forward with NIR and remote sensing Acknowledgements This research was co-funded by the NSW Department of Primary Industries and the Rural Industries Research & Development Corporation. Excellent technical support from Chris Dawe and Craig Hodges has contributed significantly to this project. Further information Brian Dunn T: 02 6951 2621 E: [email protected]