Dryland Legume Pasture Systems: Medic nodulation and nitrogen fixation


Research organisatons
Funding sources

Trial details

Researcher(s) Ross Ballard (SARDI)
Year(s) 2019
Contributor SARDI Minnipa Agricultural Centre
Trial location(s) Site 14, Minnipa Agricultural Centre, SA
Related trials
Dryland Legume Pasture Systems: Medic nodulation and nitrogen fixation locations

There are reports of low grain protein levels in wheat following medic pastures and many observations of poor medic nodulation. Previous work has shown that rhizobial inoculation can improve the nodulation of medics in the SA and Victorian Mallee, and that more generally about 50% of the populations of medic rhizobia in soils are suboptimal in their nitrogen (N) fixation
capacity. This trial aimed to:
• Determine if inoculation can improve medic nodulation at Minnipa,
• Quantify the amount of N fixed by different legumes, and
• Assess impacts on the following wheat crop.

Key messages
  • The nodulation of strand medic was below potential, but was not increased by inoculation.
  • Trigonella formed more nodules than medic, but in the end PM-250 strand medic was more productive and fixed the most N.
  • Legume inoculation (2018) increased wheat grain protein (2019). The increase could not be attributed to any measure of legume performance.
Lead research organisation South Australian Research and Development Institute
Host research organisation SARDI Minnipa Agricultural Centre
Trial funding source GRDC RnD4Profit-16-03-010
Trial funding source AWI RnD4Profit-16-03-010
Trial funding source MLA RnD4Profit-16-03-010
Trial funding source AGRR&D RnD4Profit-16-03-010
Related program Dryland Legume Pasture Systems (Rural R&D for Profit)

The Dryland Legumes Pasture Systems project is supported by funding from the Australian Government Department of Agriculture as part of its Rural R&D for Profit program, the Grains Research and Development Corporation, Meat and Livestock Australia and
Australian Wool Innovation. The research partners include the South Australian Research and Development Institute, Murdoch
University, the Commonwealth Scientific and Industrial Research Organisation, the WA Department of Primary Industries and
Regional Development, and Charles Sturt University, as well as grower groups. Project code: RnD4Profit-16-03-010.

Other trial partners Murdoch University, the Commonwealth Scientific and Industrial Research Organisation, the WA Department of Primary Industries and Regional Development, and Charles Sturt University
Download the trial report to view additional trial information


Crop type Medic
Treatment type(s)
  • Crop: Type
  • Inoculant: Rate
  • Variety: Type
Trial type Experimental
Trial design Replicated

Minnipa Agricultural Centre 2019

Sow date Not specified
Harvest date Not specified
Plot size 5m x 1.5m
Plot replication 4
Plot blocking Random
Plot randomisation Random blocks
Download the trial report to view additional method/treatment information
Trial source data and summary not available
Check the trial report PDF for trial results.
Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Site 14, Minnipa Agricultural Centre, SA Red sandy loam
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Site 14, Minnipa Agricultural Centre, SA Anthroposol
Soil Moisture Source: BOM/ANU
Average amount of water stored in the soil profile during the year, estimated by the OzWALD model-data fusion system.
Year Site 14, Minnipa Agricultural Centre SA
2019 403.6mm
2018 429.5mm
2017 443.9mm
2016 405.1mm
2015 379.2mm
2014 440.5mm
2013 402.0mm
2012 445.2mm
2011 465.2mm
2010 442.3mm
2009 474.7mm
2008 403.9mm
2007 395.3mm
2006 423.0mm
2005 379.0mm
2004 360.2mm
2003 378.0mm
2002 382.0mm
2001 444.0mm
2000 464.3mm
National soil grid Source: CSIRO/TERN
NOTE: National Soil Grid data is aggregated information for background information on the wider area
Actual soil values can vary significantly in a small area and the trial soil tests are the most relevant data where available

Soil properties



Site 14, Minnipa Agricultural Centre SA 2019

Observed climate information

Rainfall avg ann (mm) 325mm
Rainfall avg gsr (mm) 242mm
Rainfall trial total (mm) 269mm
Rainfall trial gsr (mm) 208mm

Derived climate information

Site 14, Minnipa Agricultural Centre SA


Some data on this site is sourced from the Bureau of Meteorology

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.

Trial report and links

2019 trial report

Trial last modified: 21-07-2020 13:15pm AEST