Effect of combinations of sowing time, seed rate and herbicides on ryegrass management in wheat (Roseworthy, SA)

2020
CC BY 4.0

Research organisaton
Funding source

Trial details

Researcher(s) Ben Fleet
Gurjeet Gill
Contact email gurjeet.gill@adelaide.edu.au
Contact phone +61428592825
Year(s) 2020
Contributor School of Agriculture, Food and Wine - The University of Adelaide
Trial location(s) Roseworthy campus, University of Adelaide, SA
Effect of combinations of sowing time, seed rate and herbicides on ryegrass management in wheat (Roseworthy, SA) locations
Aims

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

Key messages

A field trial was undertaken in 2020 to investigate combinations of wheat sowing time, seed rate and herbicide treatments to control annual ryegrass. Increase in wheat seed rate from 100 to 200 seeds/m2 caused a significant reduction in ARG spikes and seed set. The level of additional weed suppression from higher wheat seed rate ranged from 30-35%. As expected, both pre-emergent herbicides caused a significant reduction ARG plant density, spikes and seed production. Even though there was a general trend for Sakura to be slightly more effective than Boxer Gold, these differences were non-significant. It is somewhat disconcerting to note that even with the use of the tank mix of Sakura + Avadex Xtra, ARG was able to set more than 34,000 seeds/m2. These results highlight the need for integrating multiple weed control tactics to drive down the populations of this resilient weed. Wheat grain yield at Roseworthy ranged from 1.85 t/ha to 3.48 t/ha and with a site mean across all treatments of 2.773 t/ha. Time of sowing wheat did not have a significant effect on wheat grain yield in 2020 (P=0.168). However, wheat grain yield was significantly influenced by crop seed rate (P=0.023) and herbicide treatments (P=0.001). There was no interaction between these management factors. As seed rate increased from 100 to 200 seeds/m2, wheat grain yield steadily increased by 15%. Herbicide treatments had a highly significant (P<0.001) effect on wheat grain yield in this trial, which was not surprising considering the high ARG seedbank and weed density. Application of Boxer Gold and Sakura + Avadex Xtra increased wheat yield by 41% and 54% compared to the untreated control.

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

GRDC for providing funding for this research project.


Other trial partners Not specified
Download the trial report to view additional trial information

Method

Crop types Weed: Ryegrass Cereal (Grain): Wheat
Treatment type(s)
  • Herbicide: Type
  • Sowing: Rate
  • Sowing: Timing
Trial type
Trial design

Roseworthy campus, University of Adelaide 2020 Ryegrass

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

Roseworthy campus, University of Adelaide 2020 Wheat

Sow date 6 May and 29 May
Harvest date Not applicable
Plot size Not specified
Plot replication 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
Roseworthy campus, University of Adelaide, SA Not specified
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Roseworthy campus, University of Adelaide, SA Chromosol
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.

Roseworthy campus, University of Adelaide 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

2020 trial report



Trial last modified: 20-03-2023 16:30pm AEST