Effect of time of sowing, crop seed rate and pre-emergence herbicides on annual ryegrass management in barley


Research organisatons
Funding source

Trial details

Researcher(s) Gurjeet Gill and Ben Fleet
Contact email gurjeet.gill@adelaide.edu.au
Contact phone 08 83137744
Year(s) 2019
Contributor School of Agriculture, Food and Wine - The University of Adelaide
Trial location(s) Frances, SA, SA
Effect of time of sowing, crop seed rate and pre-emergence herbicides on annual ryegrass management in barley locations

This field trial at Frances was undertaken to investigate factorial combinations of sowing time, seed rate and herbicides on the management of annual ryegrass in barley.

Key messages

A field trial was undertaken at Frances in 2019 to investigate combinations of barley sowing time, seed rate and herbicide treatments to control annual ryegrass. The average seedbank of annual ryegrass (ARG) at the site was quite low (472 ± 143 seeds/m2), which was reflected in low plant density at the site. ARG plant density was significantly influenced by the time of sowing (P=0.037), and herbicide treatment (P=0.009). There was a 37% reduction in ARG plant density between TOS 1 (20 plants/m2) and TOS 2 (13 plants/m2). Herbicide treatment had a significant effect on ARG plant density, with Boxer Gold showing lower efficacy on ARG than Treflan and Boxer Gold + Treflan. Unlike ARG plant density, ARG spike density was not influenced by time of sowing (P=0.171). ARG spike density was significantly influenced by barley seed rate (P=0.016), herbicide treatment (P=0.01) and the interaction between TOS and herbicide treatment (P=0.019). ARG spike density was 34% and 40% lower in medium and high seed rates respectively when compared to the low seed rate. These results suggest an improvement in ARG suppression from increasing barley competiveness with increased seed rate. Barley grain yield at the site averaged 6.6 t/ha. Herbicide treatment had a small (4-6%), but significant effect (P=0.009) on grain yield with Boxer Gold < Treflan ≤ Boxer Gold + Treflan for barley yield.

Lead research organisation University of Adelaide
Host research organisation MacKillop Farm Management Group
Trial funding source GRDC 9175134
Related program N/A

We thank GRDC for providing funds for this research project and SARDI Struan for managing the trial site.

Other trial partners SARDI, Struan


Crop type Barley
Treatment type(s)
  • Herbicide: Type
  • Sowing: Rate
  • Sowing: Timing
Trial type Experimental
Trial design Randomised,Replicated,Blocked

Frances, SA 2019

Sow date Not specified
Harvest date Not specified
Plot size Not specified
Plot replication Not specified
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
Frances, SA, SA Not specified
Derived trial site soil information
Australian Soil Classification Source
Trial site Soil order
Frances, SA, SA Vertosol
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.

Frances, SA 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 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 last modified: 18-05-2020 13:50pm AEST