Knockdown mixtures for the control of ryegrass and wild radish in a spot spray (Weedseeker/Weed It) scenario


Research organisaton

Trial details

Researcher(s) Bernie Quade (Landmark)
Year(s) 2012
Contributor North East Farming Futures
Trial location(s) Northern Ag region of Western Australia, WA
Knockdown mixtures for the control of ryegrass and wild radish in a spot spray (Weedseeker/Weed It) scenario locations

To investigate alternative modes of action for the control of very low populations of ryegrass and wild radish when using a spot spraying technique during spring on spray fallow paddocks. The purpose of exploring alternative modes of action is to help prevent the onset of glyphosate resistance because the spray fallow technique is a high risk method from a resistance perspective.

Key messages

In this trial, even the conditions at the time of spraying were ideal (high humidity), Basta (group N) performed poorly on both radish and ryegrass. The group G products did not seem to provide significant additional control over and above its mixing partner. Better treatments included 4L of glyphosate (not an option from a resistance management perspective), Sprayseed + Atrazine as well as 8L of Alliance. There was a clear rate response in wild radish control with Alliance when moving from 6L to the 8L rate. Even though a high rate (and therefore cost) of Alliance is required it is a viable option because it combines group L and Q chemistry. The active ingredient amitrole (group Q), also appears to have useful activity on ryegrass at these rates.

The treatment of Sprayseed + Atrazine appeared quite effective but it would come with a caution as the 2kg of Atrazine could pose a carryover risk (only on sprayed areas) if planting a non TT tolerant crop the following year in the absence of adequate rainfall.

The lack of treatments that gave 100% control of the target weeds illustrates how dependant this system is on glyphosate, and how vulnerable the system is if we encounter a high frequency of glyphosate resistant weeds in these paddocks.

Lead research organisation North East Farming Futures
Host research organisation N/A
Related program N/A
  • Bernie Quade, Landmark Geraldton
  • Planfarm
  • AHRI
  • CSBP
  • Nufarm
  • GRDC
  • Landmark

Other trial partners Not specified
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Crop type Fallow
Treatment type(s)
  • Herbicide: Rate
Trial type Experimental
Trial design Unreplicated

Northern Ag region of Western Australia 2012

Sow date Not specified
Harvest date Not specified
Plot size Not specified
Plot replication Not specified
  • Trial Sprayed with hand boom, 2m wide, with Agrotop airmix 11001 nozzles at 2 bar, 4km/hr, 98 L/ha. 
  • Herbicides applied between 12 noon and 1pm on 2nd August 2012, under very high humidity conditions. 
  • Herbicide mixes prepared the day before and stored in 2L plastic containers. Agitated well prior to spraying.
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
Northern Ag region of Western Australia, WA Not specified
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Northern Ag region of Western Australia, WA Tenosol
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 Northern Ag region of Western Australia WA
2012 113.2mm
2011 186.7mm
2010 115.9mm
2009 121.7mm
2008 177.0mm
2007 135.1mm
2006 144.1mm
2005 126.9mm
2004 132.9mm
2003 141.0mm
2002 127.3mm
2001 117.5mm
2000 170.8mm
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



Derived climate information

No observed climate data available for this trial.
Derived climate data is determined from trial site location and national weather sources.

Northern Ag region of Western Australia WA


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

SILO weather estimates sourced from
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

2012 trial report

Trial last modified: 25-06-2019 12:55pm AEST