Herbicide resistance in barley grass populations from the low rainfall zones in South Australia

2019 - 2020

Research organisatons
Funding source
Agricultural Innovation & Research Eyre Peninsula School of Agriculture, Food and Wine - The University of Adelaide SARDI Minnipa Agricultural Centre

Trial details

Researcher(s) Amanda Cook
Ben Fleet
Gurjeet Gill
Contact email gurjeet.gill@adelaide.edu.au
Year(s) 2019 - 2020
Contributor Agricultural Innovation & Research Eyre Peninsula
Trial location(s) Multiple Site, Eyre Peninsula, SA, SA
Herbicide resistance in barley grass populations from the low rainfall zones in South Australia locations
Aims

Why do the trial? 
Barley grass possesses several biological traits that make it difficult for growers to manage in the low rainfall zone, so it is not surprising that it is becoming more prevalent in field crops in SA. A survey by Llewellyn et al. (2015) showed that barley grass has now made its way into the top 1 0 weeds of Australian cropping in terms of the area infested, crop yield loss, and revenue loss. In this survey, barley grass was ranked as the 7th most costly weed to control by the growers in SA and VIC Mallee and Mid-North, Lower Yorke and Eyre Peninsula. In a previous random survey in SA in 2012, Shergill et al. (2015) identified resistance to quizalofop in 15% of barley grass populations from Upper North and Eyre Peninsula. Additional herbicide-resistant populations have been identified since the previous survey. Growers in these regions have observed many control failures and have been collaborating with this GRDC-funded project to confirm the resistance status of their barley grass populations. 

Key messages
  • Thirty two barley grass populations were collected from grower paddocks from Eyre Peninsula and Upper North regions in 2019 and screened for resistance to major herbicide groups in 2020. This was not a random survey because most of these populations were considered difficult to control with herbicides. 
  •  All of these barley grass populations collected in 2019 from Eyre Peninsula and Upper North regions were completely killed by glyphosate and paraquat and were rated as herbicide susceptible.
  • Resistance to the FOP herbicide quizalofop was confirmed in 50% (n=16) of these targeted populations tested in 2020. In addition to this, 19% of the populations (n=6) were classified as developing resistance. 
  • Ten barley grass populations were confirmed resistant to clethodim at 250mL/ha. At the higher clethodim dose (500mL/ha), only three populations were rated as resistant. This result is consistent with research results for annual ryegrass where higher rates of clethodim can improve weed control. Growers could improve barley grass control by increasing clethodim dose but this is unlikely to be a long-term solution to the problem. 
  • Out of 1 O clethodim resistant populations, only 3 showed resistance to butroxydim at 90 g/ha and only 1 was resistant at 180 g/ha. These results are consistent with the findings from the previous year, which showed the susceptibility of many clethodim-resistant populations to butroxydim.
  • Resistance to the IMI herbicides still appears to be very low in barley grass. Only one barley grass population from Eyre Peninsula was found to be highly resistant to Intercept® and showed no reduction in plant survival or biomass. 

 

Lead research organisation School of Agriculture, Food and Wine - The University of Adelaide
Host research organisation SARDI Minnipa Agricultural Centre
Trial funding source GRDC 9176981
Related program Demonstrating and validating the implementation of integrated weed management strategies to control barley grass in the low rainfall zone farming system
Acknowledgments

We thank GRDC for funding this research through project 9176981 and the growers for submitting samples.


Other trial partners EPARF
Download the trial report to view additional trial information

Method

Crop types Other: Not specified Weed: Barley Grass
Treatment type(s)
  • Herbicide: Type
  • Management systems: Integrated weed management
Trial type Experimental
Trial design Unknown

Multiple Site, Eyre Peninsula, SA 2019 Not specified

Sow date Multiple - please see report
Harvest date Unknown
Plot size Not specified
Plot replication Not specified
Herbicide

Please see report for treatment details 

Multiple Site, Eyre Peninsula, SA 2019 Barley Grass

Sow date Not specified
Harvest date Not specified
Plot size Not specified
Plot replication Not specified
Herbicide Not specified

Multiple Site, Eyre Peninsula, SA 2020 Not specified

Sow date Not specified
Harvest date Not specified
Plot size Not specified
Plot replication Not specified
Herbicide Not specified

Multiple Site, Eyre Peninsula, SA 2020 Barley Grass

Sow date Not specified
Harvest date Not specified
Plot size Not specified
Plot replication Not specified
Herbicide Not specified
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
Multiple Site, Eyre Peninsula, SA, SA Not specified
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Multiple Site, Eyre Peninsula, SA, SA Calcarosol
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

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Climate

Derived climate information

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

Multiple Site, Eyre Peninsula, SA SA

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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

Herbicide Resistance in barley grass populations from low rainfall zones in SA



Trial last modified: 25-05-2023 15:15pm AEST