This project aims to determine if nitrogen supply is limiting uptake of sulphur in canola crops grown in the Riverine Plains region and whether sulphur uptake and yield is increased in canola when nitrogen is available in non-limiting quantities.
The 2017 project trial assessed the response to nitrogen and sulphur in canola crops of the Riverine Plains by determining:
• the influence of nitrogen and sulphur application on canola tissue content, yield and oil
• the fluctuation in nitrogen and sulphur content and nitrogen:sulphur ratio in the plant from stem elongation (GS31) to harvest (GS99)
• the optimum available soil nitrogen level for the region’s canola crops at varying sulphur application rates.

• At the Howlong site, applied nitrogen gave a yield and dry matter (DM) response, however there was no sulphur response.
• The Yarrawonga site showed a clear response to applied sulphur (S) and nitrogen (N), despite high soil sulphur levels. This suggests canola roots may not be effectively exploring the soil profile to access soil sulphur.
• The Yarrawonga site had an optimum sulphur application rate of 20kg S/ha, with yield penalties measured with sulphur rates above and below this optimal rate.
• The dry finish to the season caused significant challenges during 2017. This trial will be repeated at two sites during 2018 to understand how variable the responses to sulphur are likely to be during different seasonal conditions.