The 2016 season saw BCG researchers investigate barley variety by nitrogen (N) research with results showing interactions not commonly seen outside of laboratory experiments.
Research conducted as part of the GRDC-funded barley agronomy for the southern region project saw common barley varieties Commander, Compass, Fathom, La Trobe, Scope CL and Granger respond to different rates of N applied at sowing.
The starting soil N at the Quambatook paddock was low at 37kg N/ha, and nitrogen treatments included 0, 30, 60, 90 and 120kg N/ha up-front with no in-season urea topdressing.
The decile 10 season favoured excellent interactions and good results and provided growers with nitrogen management packages tailored to each variety to deliver maximum profit.
Because of secondary tillering, which was an issue for many in 2016, maturity cuts were used in this investigation as delays in harvesting would have resulted in yield losses.
In the decile 10 growing season the highest rate of N (120kg N/ha) proved to be the most profitable for all varieties, and due to seasonal variability and unpredictable spring periods, this rate is not practical in most seasons as it has the potential to result in losses, both in yield and on the bottom line.
When comparing the variety results from this trial there was a difference in the N by variety interaction, suggesting that there are variances in a varieties ability to utilise supplied N and convert this into grain.
Fathom was the most N efficient in this trial, converting the most supplied N to grain. Compass and Commander had the flattest N curves indicating they were the least responsive to N supplied.
BCG members can access the full results and interpretation for this trial on the website: https://www.bcg.org.au/barley-response-to-n-applied-at-sowing/
