Integration of crop competition and herbicide strategies for the management of annual ryegrass in canola (Washpool, SA)


Research organisaton
Funding source

Trial details

Researcher(s) Gurjeet Gill, Ben Fleet and Sarah Noack
Year(s) 2018
Contributor School of Agriculture, Food and Wine - The University of Adelaide
Trial location(s) Washpool, SA
Integration of crop competition and herbicide strategies for the management of annual ryegrass in canola (Washpool, SA) locations

To investigate factorial combinations of sowing time, varieties and seed rate with herbicide strategies for ryegrass management.

Key messages

Herbicide strategy 1 (HS1), which was based on atrazine pre-sowing followed by clethodim (Select) post-emergence reduced ryegrass plant density relative to the untreated control by 57%. However, use of propyzamide pre-sowing, followed by atrazine and Select + Factor (HS 2) increased ryegrass control to 77%. Canola variety had a significant effect on ryegrass spike density (P=0.002). When averaged across the sowing dates and herbicide strategies, ryegrass growing in HyTTec Trophy produced 52 spikes/m2 as compared to 78 spikes/m2 in Bonito (33% reduction). HyTTec Trophy is a new hybrid triazine tolerant variety from Nuseed, which is known for high early vigour. Herbicide strategies also had a significant effect on ryegrass spike density (P<0.001). Ryegrass grown without any selective herbicide treatment (control – HS3) produced 128 spikes/m2 as compared to 40 spikes/m2 in HS1 and 29 spikes/m2 in HS2. This works out to 69% reduction in HS1 relative to the control and 78% reduction in HS2. Herbicide strategies had the largest effect on canola yield (P<0.001). HS1 and 2 produced canola yield of around 0.8 t/ha, which was almost 50% greater than the yield obtained in the control.

Lead research organisation School of Agriculture, Food and Wine - The University of Adelaide
Host research organisation N/A
Trial funding source GRDC 9175134
Related program GRDC - Weeds

GRDC for providing funds for this research and the local grower for the land for the trial.

Other trial partners Hart Field Site Group
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Crop type Canola
Treatment type(s)
  • Herbicide: Type
  • Sowing: Rate
  • Sowing: Timing
  • Variety: Type
Trial type Experimental
Trial design Randomised,Replicated,Blocked

Washpool 2018

Sow date Not specified
Harvest date Not specified
Plot size Not specified
Plot replication Not specified
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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
Washpool, SA Not specified
Derived trial site soil information
Australian Soil Classification Source
Trial site Soil order
Washpool, SA Anthroposol
National soil grid Source
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.

Washpool SA

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

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.

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Trial last modified: 20-09-2019 16:31pm AEST