Therese McBeath, Rick Llewellyn, Bill Davoren, Willie Shoobridge (CSIRO), Michael Moodie and Mick Brady (MSF)
|Contributor||Mallee Sustainable Farming Inc.|
Site 5, Loxton, SA
Sandy soil types of the Northern Mallee often underperform despite good weed management and increased inputs of nitrogen and sulfur. There is still a yield gap that can be addressed, with anecdotal evidence of unused water commonly remaining in the soil at depths of approximately 60cm at harvest.
After several years of demonstrating the value to wheat production of increased nitrogen inputs on sands at Karoonda, it was time to explore nutrition packages at a broader set of Mallee sites.
• The highest yield in 2016 at Loxton could be achieved with either 40 kg N/ha as urea or 20 kg N/ha as Zn-coat urea or Zn-enriched MAP.
• Compared to applying 20 kg N/ha as normal urea, using Zn-
coated urea (20 kg N/ha) or Zn-enriched MAP with urea (20 kg N /ha) increased yield by over 20%.
• This is the second consecutive season that Zn coated Urea at sowing (20kg N/ha) has significantly increase yield compared to normal Urea (20 kg N /ha).
• Applying foliar Zn has not increased yield at this site in 2015 or 2016.
• Nitrogen was a key driver of wheat productivity again, with 40 kg/ha N at sowing increasing yield by over 20% compared to 20 kg/ha N at sowing, but water use efficiency remained poor on this sandy soil.
• There was also no benefit in delaying N application at Ouyen, however very high rates (60-80 kg/N ha) using higher late application rates increased yield on the midslope.
• In 2016 there was a large difference in yield between the midslope (2.90 t/ha) and the nearby sand dune (0.86 t/ha) at Ouyen which could not be closed through the addition of N, S and Zn to the sand.
|Lead research organisation||
Mallee Sustainable Farming Inc.
|Host research organisation||
Commonwealth Scientific and Industrial Research Organisation
|Trial funding source||GRDC MSF00003|
Maintaining profitable farming systems with retained stubble
We thank Bulla Burra (Loxton) and the Hastings family (Ouyen) for hosting the field sites. Thanks to Navneet Aggarwal for technical assistance. Thanks to Jeff Braun and Lou Flohr for discussions around trial design. Thanks to Colin Rivers and Ros Baird for preparing granular Zn fertilisers. This research is funded by GRDC and CSIRO Agriculture and Food (project MSF00003).
|Other trial partners||Not specified|
28 cm row spacing
|Sow date||27 May 2017|
|Harvest date||Not specified|
|Plot size||Not specified|
|Plot replication||Not specified|
All plots received a pre-sowing application of 33 kg/ha of potassium sulfate to eliminate K and S as confounding issues and 10 kg P/ha at sowing as triple superphosphate, except for the treatment receiving MAP. All plots received an in-crop foliar application of Cu and Mn.
1.5 L/ha of trifluralin pre-sowing
SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol 16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.