Weed Resistance to Glyphosate in Southern Europe: Present and Future Perspective.

1. University
of
Córdoba
Roundup Ready ® Maize symposium: The
European Perspective
Weed Resistance to Glyphosate in Southern Europe:
Present and Future Perspective.
Dr. Rafael De Prado and Fidel González-Torralva
University of Cordoba, Spain

2. Main crops produced in the Mediterranean Region
Roundup Ready® Maize symposium: The European Perspective

3. University
of SUSTAINABLE AGRICULTURE
Córdoba
Is that in which the production systems permit the
obtainment of a continuous benefit from the use of
water, soil, genetic resources, etc. to meet the
current needs of the population without destroying
the basic natural resources for future generations.
Castillo, 1992
Roundup Ready® Maize symposium: The European Perspective

4. University
of
Córdoba
Evolution of herbicides use in Spain
70
60
50
40 1999
2004
30
2009
20
10
0
Wheat Olive Stone fruit Vineyard Citrus
Roundup Ready® Maize symposium: The European Perspective

5. University
of
Córdoba RESISTANCE
The Weed Science Society of America (WSSA)
defines herbicide resistance as
“the inherited ability of a plant to survive and
reproduce following exposure to a dose of
herbicide normally lethal to the wild type”.
Roundup Ready® Maize symposium: The European Perspective

6. Distribution of Resistant Weed Biotypes in Southern Europe
Roundup Ready® Maize symposium: The European Perspective

7. Resistance mechanisms in weeds
University Non target site
of
Córdoba
Foliar surface
Absorption
Cuticule
Apoplast
Systematization
Translocation
Metabolization
Herbicide
application Resistant Plant
Roundup Ready® Maize symposium: The European Perspective

8. Resistance mechanisms in weeds
University Target site
of Córdoba
Target site
modification
Overexpression
Herbicide
application Resistant Plant

9. University
of
MULTIPLE RESISTANCE
Córdoba
ALS INHIBITORS ACCase INHIBITORS PSII INHIBITORS
SUSCEPTIBLE
BIOTYPE
DETOXIFICATION SYSTEM
RESISTANT
BIOTYPE
STOP ACCase STOP PSII
Roundup Ready® Maize symposium: The European Perspective

10. Evolution of ALS Resistance in Southern Europe
30
University
of 25
Number of resistant species
Córdoba
20
15
10
Evolution of PS II (C1) Resistance in Southern Europe
5 World: 107
70 Southern Europe : 26
0
60
1990 1995 2000 2005 2010
Number of resistant species
50 Year
40
30
Evolution of ACCase Resistance in Southern Europe
20 30
World: 68
10 Southern Europe : 59 25
Number of resistant species
0
20
1975 1980 1985 1990 1995 2000
Year
15
10
5 World: 38
Southern Europe : 26
0
1990 1995 2000 2005 2010
Year
Roundup Ready® Maize symposium: The European Perspective

11. Evolution of Glyphosate Resistance in Southern Europe
University
of
Córdoba
6
5
RESISTANT SPECIES
4
3
2
1
0
2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
YEAR
World: 18
Southern Europe : 5
Roundup Ready® Maize symposium: The European Perspective

12. WORST WEEDS IN THE MEDITERRANEAN REGION: ORCHARDS AND OLIVE TREES
Ecbalium elaterium
Conium maculatum
Conyza spp
Cuscuta campestris Euphorbia helioscopia Malva parviflora

13. WORST WEEDS IN THE MEDITERRANEAN REGION: ORCHARDS AND OLIVE TREES
REGION:
Avena sterilis Paspalum distichum
Lolium multiflorum Lolium rigidum Cyperus rotundus

14. Evolution of Glyphosate Resistance in Southern Europe
University
of
Córdoba
Main differences between glyphosate R and S Lolium
multiflorum biotypes.
R/S factor depends of growth stage.
Shikimate does not accumulate in R biotypes.
Absorption and translocation of 14C-glyphosate in S is higher than R
biotypes.
Spray retention is higher in S biotypes.
Mutations in EPSPS have been founded in R biotypes.
Roundup Ready® Maize symposium: The European Perspective

15. University
of
Córdoba
ED50 Evolution of Lolium multiflorum
treated with glyphosate
1500 R
S
1000
-1
g ai ha
500
0
13 21 55-55 65
Growth Stage (BBCH)
Roundup Ready® Maize symposium: The European Perspective

16. Shikimic Acid (Shikimate) Pathway
University
of
Córdoba
AShikimate accumulation in L.
multiflorum biotypes
1,6
Shikimic acid (mg g-1 fresh weight)
)
1,4
1,2
1
0,8
R Biotype
0,6
S Biotype
0,4
0,2
0
0 24 48 72 96
Hours after treatment

17. Retention and contact angle in L. multiflorum treated with
University glyphosate
of
Córdoba
Adaxial Surface
µL spraying solution
g-1 dry matter Angle (degrees)
S R S R
1,763b 1,265a
62,4 (2,83) 112,9 (5,00)
Major of 90º Minor of 90º
θ = 180 – tan-1[(x.b2)/(y.a2)] θ = 2.tan-1(h/x)
a
b
x
y
θ
Unpublished data, 2010
Roundup Ready® Maize symposium: The European Perspective

18. Wax differences between R and S L. multiflorum biotypes
University
of
Córdoba
2µm²
CAD software quantification
Area Covered by Wax (%)
S R
42,9 (0,66) 102,6 (2,38)
Roundup Ready® Maize symposium: The European Perspective

19. Absorption and translocation of 14C-Glyphosate in R and S biotypes of
University glyphosate resistant L. multiflorum.
of
Córdoba
48 hours after 14C-Glyphosate
application
R S

20. Protein Alignment of EPSPS Glyphosate Resistant
University
of
Lolium spp.
Córdoba
*Arrows indicate amino acid mutations sites
Roundup Ready® Maize symposium: The European Perspective

21. Glyphosate (2250 g ai ha-1) treatment in olive orchard
University with glyphosate resistant L. multiflorum
of
Córdoba
0 DAT 15 DAT
30 DAT 75 DAT

22. University
of
Efficacy (%) of herbicides mixture with glyphosate applied in
Córdoba
glyphosate-resistant L. multiflorum.
DAT
Herbicide
15 30 45 60 75
Untreated 0,0±0,0c 0,0±0,0c 0,0±0,0c 0,0±0,0c 0,0±0,0c
G1125 54,0±12,3b 47,4±9,2b 47,3±7,3b 42,1±6,2b 40,5±6,4b
G2250 61,2±8,7bc 67,4±6,1bc 62,7±10,2bc 60,2±7,1bc 57,2±7,3b
G1125+O 58,2±9,2b 62,8±8,0bc 53,1±9,3b 52,1±6,8b 52,2±10,4b
G1125+F 49,1±8,3b 99,1±2,7a 100,0±0,0a 100,0±0,0a 100,0±0,0a
G1125+C 79,1±6,3ab 100,0±0,0a 100,0±0,0a 100,0±0,0a 100,0±0,0a
G1125+Q 71,1±4,0ab 100,0±0,0a 100,0±0,0a 100,0±0,0a 100,0±0,0a
G=glyphosate (g ae ha-1); O=orosorb (0,8% v/v); F=flazasulfuron (50 g ai ha-1);
C=clethodim (120 g ai ha-1) and Q=quizalofop (50 g ai ha-1).

23. Glyphosate at 2160 g ai ha-1
30 DAT 45 DAT
0 DAT
60 DAT Control 60 DAT

24. Visual assessment of different herbicide treatments on Conyza spp.
DAYS AFTER TREATMENT
TREATMENT 15 30 45 60
A 0,0 ± 0,0 0,0 ± 0,0 0,0 ± 0,0 0,0 ± 0,0
B 71,7 ± 12,6 80,0 ± 5,0 80,0 ± 5,0 85,0 ± 13,2
C 85,0 ± 8,7 100,0 ± 0,0 100,0 ± 0,0 100,0 ± 0,0
D 18,3 ± 10,4 30,0 ± 5,0 41,7 ± 7,6 56,7 ± 5,8
E 26,7 ± 5,8 70,0 ± 5,0 80,0 ± 10,0 93,3 ± 2,9
F 18,3 ± 2,9 20,0 ± 10,0 20,0 ± 5,0 31,7 ± 7,6
G 60,0 ± 5,0 60,0 ± 10,0 65,0 ± 5,0 70,0 ± 10,0
H 55,0 ± 10,0 81,7 ± 10,4 85,0 ± 5,0 88,3 ± 7,6
I 40,0 ± 0,0 70,0 ± 10,0 76,7 ± 2,9 96,7 ± 2,9
J 68,3 ± 7,6 88,3 ± 7,6 96,7 ± 2,9 100,0 ± 0,0
K 60,0 ± 5,0 68,3 ± 2,9 71,7 ± 2,9 70,0 ± 17,3
A Control
B Glyphosate 2160 g ai ha-1
C Glyphosate 4320 g ai ha-1
D Flazasulfuron 200 g ha-1
E Glyphosate 2160 g ai ha-1+ Flazasulfuron 200 g ha-1
F Saflufenacil 20 g ha-1+ Dash 0,75%
G Glyphosate 2160 g ai ha-1+ Saflufenacil 20 g ha-1 + Dash 0,75%
Glyphosate 2160 g ai ha-1 + Saflufenacil 20 g ha-1 + Dash 0,75%
H
** Saflufenacil 20 g ha-1 + Dash 0,75%
I Fusta 8 L ha-1
J Fusta 8 L ha-1 + glyphosate 720 g ai ha-1
K Glyphosate 2160 g ai ha-1 + Saflufenacil 20 g ha-1 + Aceite 1 %

25. University “Would it be possible to have a sustainable crop
of
Córdoba
management in the future using herbicides?”
Good agricultural …We are
more than
6,500
practices… millions of
people

26. University
of
Córdoba Innovation in Agro-Technologies are
Key-Factors to Satisfy Future Food Demand
Trillion Kilocalories /Year
7.37 2.13 11.28
10.6 0.52 Reserve
10.0
2.29
1.72
5.1 5.17 1.23
5.0 -0.13
Improvements
-1.12
Demand Supply Demand Arable Conversion Gap Fertilizer Irrigation Traditional Bio- Supply
1995 2025 Land Loss Crop technology 2025
Protection and
Seeds
Source: Kern, M., 1998
Future of Agriculture fig. 2

27. Summarize
University
of
Córdoba
- Resistance to herbicides is wide spread in Europe as well as globally ( see www.weedscience.org ).
www.weedscience.
- Confirmed glyphosate resistant weed biotypes of Lolium rigidum, Lolium multiflorum, Conyza canadensis
rigidum, multiflorum,
and Conyza bonariensis are known in Europe, these resistant biotypes are exclusively spread in perennial
crops like vineyards, citrus plantations and olive groves. They were selected because there was a sole
groves.
reliance on glyphosate in these crops to control weeds.
weeds.
- Glyphosate resistant weed biotypes can be managed by: by:
•glyphosate applications when the plants are most susceptible
•complementary cultural practices, like tillage or mowing
•herbicide sequences and/or tank-mixes
tank-
-Mixture of auxinic herbicides alone and/or with glyphosate are a good solution to control dicotiledonea
weeds.
weeds.
-ALS and ACCase inhibitor herbicides mixture with glyphosate must be managed with care. In terms of
care.
resistance development they can be named “High Risk Herbicides.
Herbicides.

28. THANK YOU FOR YOUR
ATTENTION