Researcher(s) |
Ben Fleet |
---|---|
Year(s) | 2019 |
Contributor | SARDI Minnipa Agricultural Centre |
Trial location(s) |
Buckland Park, SA
|
Related trials |
Change in sowing time can have multiple effects on crop-weed competition. Delayed sowing can provide opportunities to kill greater proportion of weed seedbank before seeding the crop, but weeds that establish in late sown crops can be more competitive on a per plant basis. This is one of reasons why farmers who have adopted early seeding have reported excellent results in crop yield and weed suppression. Therefore, it is important to investigate sowing time in combination with other practices across different rainfall zones. The review of Widderick et al. (2015) also recommended research on sowing time in many crops. Delayed sowing can also reduce crop yield so the gains made in weed control may be completely nullified by the yield penalty.
There has been some research already on crop seed rate on weed suppression but none of these studies have investigated the benefits of higher crop density in factorial combinations with sowing time and herbicide treatments. Crop seed rate is an easy tactic for the growers to adopt provided they are convinced of its benefits to weed management and profitability. Furthermore, growers in the low rainfall areas tend to be reluctant to increase their seed rate due to concerns about the negative impact of high seed rate on grain screenings.
This field trial at Minnipa was undertaken to investigate factorial combinations of sowing time, seed rate and herbicides on the management of annual ryegrass in barley.
Lead research organisation |
School of Agriculture, Food and Wine - The University of Adelaide |
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Host research organisation |
School of Agriculture, Food and Wine - The University of Adelaide |
Trial funding source | GRDC 9175134 |
Related program | N/A |
Acknowledgments |
The authors thank Bruce and Kathryn Heddle for hosting the site. Malinee Thongmee and Hue Thi Dang (University of Adelaide), Fiona Tomney, Steve Jeffs, Bradley Hutchings and Katrina Brands (SARDI) for their technical input to the trial. We also acknowledge the investment from GRDC for the research into ‘Cultural management for weed control and maintenance of crop yield’ (9175134). |
Other trial partners | SARDI Minnipa Agricultural Centre |
Crop types | Weed: Ryegrass Cereal (Grain): Barley |
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Treatment type(s) |
|
Trial type | |
Trial design |
Sow rate or Target density | Not specified |
---|---|
Sow date | Not specified |
Harvest date | Not specified |
Plot size | Not specified |
Plot replication | Not specified |
Plot randomisation | Not specified |
Herbicide | Not specified |
Sow rate or Target density | Multiple - please see report |
---|---|
Sow date | TOS 1: 4 May; TOS 2: 24 May |
Harvest date | Unknown |
Plot size | 105m x 10m |
Plot replication | 3 |
Plot randomisation | split plot design with three replicates |
Herbicide |
Multiple- please see report |
# |
Treatment 1
|
Treatment 2
|
---|---|---|
1 | █ Operation | █ Details |
2 | █ Location | █ Minnipa, SA |
3 | █ Seedbank soil cores | █ 11 April |
4 | █ Plot size | █ 1.5 m x 10 m |
5 | █ Seeding date | █ TOS 1: 4 May TOS 2: 24 May |
6 | █ Fertiliser | █ At sowing – DAP (18:20:0:0) @ 60 kg/ha |
7 | █ Variety | █ Compass barley |
8 | █ Seeding rate | █ 100 seeds/m2 150 seeds/m2 200 seeds/m2 |
9 | █ Herbicides | █ 4 May and 24 May (applied just before seeding) Boxer Gold 2.5 L/ha IBS Trifluralin 1.5 L/ha IBS Control (knockdown treatment only) |
10 | █ Trial design | █ split plot design with three replicates |
11 | █ Measurements | █ pre-sowing weed seedbank, crop density, weed density, ARG spike density, ARG seed production, wheat grain yield |
# |
Treatment 1
|
Treatment 2
|
Treatment 3
|
---|---|---|---|
1 | █ | █ Rainfall (mm) | |
2 | █ Month | █ 2019 | |
3 | █ Jan | █ 4.0 | |
4 | █ Feb | █ 1.2 | |
5 | █ Mar | █ 0.2 | |
6 | █ Apr | █ 11.0 | |
7 | █ May | █ 57.2 | |
8 | █ Jun | █ 56.4 | |
9 | █ Jul | █ 15.6 | |
10 | █ Aug | █ 19.2 | |
11 | █ Sep | █ 53.6 | |
12 | █ Oct | █ 3.4 | |
13 | █ Nov | █ 7.0 | |
14 | █ Dec | █ 6.4 | |
15 | █ Annual total | █ 235.2 | |
16 | █ GSR total | █ 216.4 |
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.