1. Home ::  
  2. Trial Search

Identifying the causes of unreliable N fixation by medic based pastures

2016

Research organisation
Funding source
SARDI Minnipa Agricultural Centre
<abbr title='South Australian Grain Industry Trust Fund'>SAGIT</abbr>

Trial details

Researcher(s) Brian Dzoma (SARDI)
Year(s) 2016
Contributor SARDI Minnipa Agricultural Centre
Trial location(s) Piednippie, SA
Pingbong, SA
Related trials
Identifying the causes of unreliable N fixation by medic based pastures locations
Aims

To assess the impact of soil nutrition, current herbicides, adjuvants and rhizobial inoculants on N fixation by medics under field conditions typical of the upper Eyre Peninsula. 

Key messages
  • Growers should be aware that the application of certain broad-leaved herbicides can result in a reduction in shoot dry matter of medic pastures.
  • Application of a full label rate of Agritone 750 (late) resulted in the largest reduction of shoot dry matter.
  • Applying P to a soil with low P reserves when establishing a medic pasture boosts shoot and root dry matter, improves root health and improves N fixation.
  • Growers should also be aware that the use of herbicides can reduce nodulation and N2- fixation in medic pastures.
Lead research organisation SARDI Minnipa Agricultural Centre
Host research organisation N/A
Trial funding source SAGIT SARDI515
Related program N/A
Acknowledgments

Thanks to Greg Scholz and Brent Cronin for allowing us to have the trials at their properties, and Andy Bates for his input in this project. This project is funded from SAGIT (SARDI 1515: Identifying the causes of unreliable N fixation by medic based pastures).
Other trial partners Not specified
Download the trial report to view additional trial information

Method

Crop type Pasture: Medic
Treatment type(s)
  • Crop : Type
  • Fertiliser : Rate
  • Herbicide : Timing
  • Herbicide : Type
Trial type Experimental
Trial design Replicated

Piednippie 2016

Sowing machinery

Two replicated field trials were established on Eyre Peninsula in 2016; one representative of typical mallee environments in SE Australia (Greg Scholz - Pinbong) and the other on a grey highly calcareous sandy soil (Brent Cronin - Piednippie). Background rhizobia populations, soil moisture and soil fertility were determined prior to seeding. Treatments (Table 1), to simulate herbicide residues were imposed on 27 January and the trials were later sown on 11 May (Piednippie) and 12 May (Pinbong) with all nutrition treatments applied at sowing. Both trials were sown as a split plot design with the main plots comprising the strand medic varieties Angel and Herald, and management options as subplots (nutrition, herbicides and inoculants) applied to both varieties. Post emergent herbicide treatments were applied after the third trifoliate leaf stage on 5 July 2016 at a water rate of 100 L/ha, with the exception of the Agritone 750 (2) and Agritone 750 - late treatments that were lat

Sow date 11 May 2016
Harvest date Not specified
Plot size 6m x 1.5m
Plot replication 3
Fertiliser

&

Nutrition

Delivered as

 

 

Nitrogen

Urea

100 kg

Phosphorou

Herbicide

Table 1 Treatment details

Treatment

Active ingredient

Chemical group

Application rate (units/ha)

Post-emergence

 

 

 

Agritone 750

750 g/L MCPA (as dimethylamine salt)

I

330 ml

Agritone 750 (2)

750 g/L MCPA (as dimethylamine salt)

I

330 ml

Agritone 750 - Late

750 g/L MCPA (as dimethylamine salt)

I

330 ml

Broadstrike

800 g/kg Flumetsulam

B

25 g + Uptake oil

Tigrex

250 g/L MCPA as the ethyl hexyl ester; 25 g/L Diflufenican

F                  I

100 ml + 200 ml *wetter

Tigrex +                        Verdict

250 g/L MCPA as the ethyl hexyl ester; 25 g/L Diflufenican

F                  I

75 ml + 200 ml *wetter

520 g/L Haloxyfop

A

100 ml

LVE Agritone

570 g/L MCPA as the 2-ethylhexyl ester

I

250 ml + 200 ml *wetter

LVE Agritone + Verdict

570 g/L MCPA as the 2-ethylhexyl ester

I

250 ml + 200 ml *wetter

520 g/L Haloxyfop

A

100 ml

Rustler

500 g/L Propyzamide

K

1 L

Verdict

520 g/L Haloxyfop

A

75 ml + uptake oil

Herbicide residues

 

 

 

Intervix

33 g/L Imazamox; 15 g/L Imazapyr

B

50 ml

Logran

750 g/kg Triasulfuron

B

1.25 g

2,4-D Amine

625 g/L 2,4-D (as dimethylamine salt)

I

1 L

Nutrition

Delivered as

 

 

Nitrogen

Urea

100 kg

Phosphorous

Phosphoric acid

10 kg

Phosphorous

Phosphoric acid

5 kg

Zinc

Zinc sulphate

2 kg

Control 1

Inoculated

Control 2

Not inoculated

 

 

*Wetter = BS1000

Pingbong 2016

Sowing machinery Not specified
Sow date Not specified
Harvest date Not specified
Plot size Not specified
Plot replication Not specified
Fertiliser Not specified
Herbicide Not specified
Download the trial report to view additional method/treatment information

Download results

Trial results Effect of variety on growth characteristics at Piednippie in 2016

# Variety
 Biomass (t/ha) Total nodules/plant (nodules/plant) Effective nodules (nodules/plant) Ineffective nodules (nodules/plant) Root Damage Score ((0 Good - 15 Bad)) Root DM (mg/plant) Shoot DM (mg/plant)
1 █ Angel 1 7.9 5.8 2.1 3.3 13.3 146.4
2 █ Herald 1 6.8 5.1 1.7 3.1 13.5 154.7

Biomass t/ha

Loading

Effective nodules nodules/plant

Loading

Ineffective nodules nodules/plant

Loading

Root Damage Score (0 Good - 15 Bad)

Loading

Root DM mg/plant

Loading

Shoot DM mg/plant

Loading

Total nodules/plant nodules/plant

Loading

Trial results Effect of variety on growth characteristics at Pingbong in 2016

# Variety
 Biomass (t/ha) Total nodules/plant (nodules/plant) Effective nodules (nodules/plant) Ineffective nodules (nodules/plant) Root Damage Score ((0 Good - 15 Bad)) Root DM (mg/plant) Shoot DM (mg/plant)
1 █ Angel 1 7.9 5.8 2.1 3.3 13.3 146.4
2 █ Herald 1 6.8 5.1 1.7 3.1 13.5 154.7

Biomass t/ha

Loading

Effective nodules nodules/plant

Loading

Ineffective nodules nodules/plant

Loading

Root Damage Score (0 Good - 15 Bad)

Loading

Root DM mg/plant

Loading

Shoot DM mg/plant

Loading

Total nodules/plant nodules/plant

Loading
Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Piednippie, SA Grey calcareous sandy loam
Pingbong, SA Not specified
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Piednippie, SA Calcarosol
Pingbong, SA Calcarosol
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 Piednippie SA Pingbong SA
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000

Climate

Piednippie SA 2016

Observed climate information

Rainfall avg ann (mm) 379mm
Rainfall avg gsr (mm) 304mm
Rainfall trial total (mm) 485mm
Rainfall trial gsr (mm) 323mm

Derived climate information

Piednippie SA

Pingbong SA

Piednippie SA

NOTE: Exact trial site locality unknown - Climate data may not be accurate
Loading
Loading
Loading

Pingbong SA

NOTE: Exact trial site locality unknown - Climate data may not be accurate
Loading
Loading
Loading

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

2016 trial report



Trial last modified: 11-12-2019 14:45pm AEST