Sustaining no-till & glyphosate
D’Emden et al 2009
Resistance SurveysFrequency of herbicide resistance
in Western Australia
Mechelle Owen, Michael Walsh & Stephen Powles Australian Herbicide Resistance Initiative
www.ahri.uwa.edu.au
30 plus sites visited in each region
Sampled every 5km
Crop variety testing zones
H
Multiple Resistant Annual Ryegrass Populations
Multiple resistance Wild Radish
84%H1/M1/L1
65%H2/M2/L2
28%H4/M4/L4
39%H3/M3/L3
Years to resistance for different herbicides - USA
0
5
10
15
20
25
30
35
0 10 20 30 40 50
Years of use
Res
ista
nt
spec
ies
ALS Inhibitors
ACCase inhibitors
Triazines
Glyphosate
(Roundup) glyphosate @ 450g/ha
R S
(Gramoxone) paraquat @ 200g/ha
R S
R S
(Hoegrass) diclofop @ 1000g/ha
R S
(Verdict) haloxyfop @ 52g/ha
(Fusilade) fluazifop @ 100g/ha
R S
(Achive) tralkoxydim @ 152g/ha
R S
R S
(Sertin) sethoxydim @ 100g/ha
The Rise and Rise of Glyphosate
Australian Herbicide Resistance Initiative University of Western Australia
“Glyphosate is as important to world agriculture as penicillin is to human health” Powles 2010
Glyphosate: a once in a life time herbicide
2009 Global Herbicide Sales Source: Cropnosis Ltd
0 1000 2000 3000 4000 5000 6000
Glyphosate
Paraquat
Mesotrione
Glufosinate
Acetochlor
2,4-D
Mesosulfuron
S-Metalochlor
Fenoxaprop
Clodinafop
Nicolsulfuron
Atrazine
Sales ($m)
1974
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
Knockdown use Introduction of RR Crops
History of glyphosate
$ 5 billion
Global GM Crops (million ha)
0
20
40
60
80
100
120
140
160
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010
Source: ISAAA
• Soybean, maize, cotton and canola
• 90% RR
• 80% globally traded soybeans are RR
• 60% globally traded canola are RR
Argentine GM soybeans v No-till farming
0
4
8
12
16
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
GM
So
ybea
ns
(m h
a)
0
4
8
12
16
20
No
-til
l F
arm
ing
(m
ha)
GM SoybeansNo-till farming
Trigo J & Cap J
Argentine RR soybeans & No-till
RR Soybeans
99% RR
How to be in
herbicide resistance
Corn, Cotton and Soybean
Belt
Corn 40 m haSoybean 30 m haCotton 5 m ha
Corn, Cotton and Soybean
Belt
Corn 40 m ha (85% glyphosate resistant)Soybean 30 m ha (95% glyphosate resistant)Cotton 5 m ha (95% glyphosate resistant)
RR soybean removed previous herbicide diversity
GLYPHOSATE
BELT
Palmer Amaranth in RR CottonPalmer Amaranth in RR Cotton
Learning from GM cropping in Canada
Cereal, CanolaCorn/Soy
Learning from Canada
• Wheat the major crop• GM Canola dominant but with diversity
- Liberty Link Canola- Clearfield Canola
- RR Canola – 80%Diversity in crops and herbicides=
Sustainability
Glyphosate Resistance in Australia
133 cases of resistant ryegrass
Other Species - Liverseed grass (3) - Awnless barnyard
grass (18) - Windmill grass (1)
- Fleabane (8)
State
No of populations
SA 49
NSW
48
WA 22
Vic 14
Photo: Andrew Heinrich
Glyphosate resistance• Not limited to broadacre situations resistance
has been found in:• Vineyards• Orchards• Roadside verges• Railway lines• Irrigation channels• Airstrips
• Fencelines/crop margins – using glyphosate as only method for weed control will lead to evolution of resistance
GLYPHOSATE STILL WORKING ON MOST FARMS – KEEP IT THAT WAY
Photo: Andrew Heinrich
Probability of glyphosate resistance
0
0.2
0.4
0.6
0.8
1
0 5 10 15 20 25 30
Year
Pro
bab
ilit
y o
f re
sist
ance
Glyphosate every year
Glyphosate/paraquat rotation
Glyphosate then paraquat sequence
Cumulative probability distributions for predicted evolution of glyphosate resistance in annual ryegrass in a 30-year simulation of a Wheat-Lupin-Wheat-Canola rotation with no tillage at sowing
Neve et al 2003 weed research
Harvest weed seed mgt, double knock!
• Up to 85% of ryegrass seed “harvested” can be collected in the chaff fraction
Burn Narrow windrows
Photo: Piers Blake
HSD – double knock
Bale everything!!
0
50
100
150
200
250
300
-10 0 10 20 30 40 50 60 70 80 90 100 110
Distance (m)
Wil
d r
ad
ish
se
ed
(m
2 )
No cart
Cart
Targeting weed seeds allows crop production to continue
- Chaff collection
- Harvest residue baling
- Windrow burning
- Chaff destruction