Phytophthora infestans
• Caused the Irish potato famine of 1845-1849
• Causal agent of late blight, #1 disease of potato
• Without agrichemicals, late blight can destroy a crop in 10-14 days
Late blight control • Regular spraying can limit losses to 15% but fungicide resistance can develop – e.g.
metalaxyl
• Spraying costs ~ £500 per ha in the UK (10 – 15 sprays/season) – ~€60M / yr (UK) – ~€4Bn / yr (Europe)
• Fungicide restrictions mean that some chemicals will become unavailable
• Sanitary measures – eliminate primary inoculum, early planting, crop walking –
often ineffective due to speed of epidemic
• Resistance genes
Potato resistance genes against late blight
• Cultivated potato originally possessed virtually no resistance genes against late blight
• Resistance genes were introduced by breeding using a wild potato species • The late blight pathogen has changed to avoid recognition by the resistance genes
and so we are heavily reliant on pesticides
• More resistance genes have been identified in other wild potatoes
Plant disease resistance (R) genes confer resistance to diverse organisms
• Bacteria
• Viruses
• Fungi
• Oomycetes
• Nematodes
• Insects
• Parasitic plants
Potato late blight
Resistant - carries Rpi-blb1/RB Sensitive
How can we use these new resistance genes?
• Breeding in potato is a long complex process
• Traditional breeding can also introduce many undesirable traits which need to be removed
– Few, small tubers – Posionous alkaloid content – Not adapted to European daylength
• Genetic modification can be used to transfer a single resistance gene into
cultivated potato
• Techniques are available that ensure that only plant DNA is transferred into the recipient plant
• This is PRECISION BREEDING, we are introducing resistance genes from one potato species into another, without the transfer of undesirable traits
Rpi (Resistance to P. infestans) genes
• 12 R genes (R1-R11) were bred in from S. demissum - all have broken
New Rpi genes have been identified from wild Solanum species
• Rber from S. berthaultii
• Rpi-blb1/RB, Rpi-blb2, Rpi-blb3 and Rpi-abpt from S. bulbocastanum
• Rpi-pnt1 from S. pinnatisectum
• Rpi-phu1 from S. phureja
R1, R3a, Rpi-blb1/RB , Rpi-blb2, Rpi-blb3, Rpi-abpt, Rpi-vnt1, Rpi-mcq1 cloned,
Rpi-blb1 & 2 are currently were being trialled as transgenes by BASF in Europe (“Fortuna” potato (var Agria) - expected approval 2014 or 2015)
S. venturii
Argentina, Salta province, Chicoana department
Rpi-vnt1.1
S. mochiquense
Peru
Rpi-mcq1.1
Rpi genes isolated in TSL and tested in GM field trial
Rpi-vnt1.1 isolated from S. venturii
effective against all major isolates naturally occurring in UK
Rpi-mcq1 isolated from S. mochiquense
effective against some isolates, but not the dominant blue_13 and pink_6
blue_13
pink_6
We needed to test if Rpi-vnt1 and Rpi-mcq1.1 give resistance in the field to Pi...... No tests for yield, taste or cooking quality. Small transgenic plants were put in soil but control plants were grown from tubers (Maris Piper and Desiree)
More info: http://www.tsl.ac.uk/gmtrial or http://ww2.defra.gov.uk/
08/06/2010
11/06/2010
16-09-2011
• Late blight infection occurred
late in 2011
• Plants had begun to senesce
already
• But still a clear difference
between the GM lines and
non-GM controls
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
May
1, 2
01
0
May
4, 2
01
0
May
7, 2
01
0
May
10
, 20
10
May
13
, 20
10
May
16
, 20
10
May
19
, 20
10
May
22
, 20
10
May
25
, 20
10
May
28
, 20
10
May
31
, 20
10
Jun
3, 2
01
0
Jun
6, 2
01
0
Jun
9, 2
01
0
Jun
12
, 20
10
Jun
15
, 20
10
Jun
18
, 20
10
Jun
21
, 20
10
Jun
24
, 20
10
Jun
27
, 20
10
Jun
30
, 20
10
Jul 3
, 20
10
Jul 6
, 20
10
Jul 9
, 20
10
Jul 1
2, 2
01
0
Jul 1
5, 2
01
0
Jul 1
8, 2
01
0
Jul 2
1, 2
01
0
Jul 2
4, 2
01
0
Jul 2
7, 2
01
0
Jul 3
0, 2
01
0
Au
g 2
, 20
10
Au
g 5
, 20
10
Au
g 8
, 20
10
Au
g 1
1, 2
01
0
Au
g 1
4, 2
01
0
Au
g 1
7, 2
01
0
Au
g 2
0, 2
01
0
Au
g 2
3, 2
01
0
Au
g 2
6, 2
01
0
Au
g 2
9, 2
01
0
Sep
1, 2
01
0
Sep
4, 2
01
0
Sep
7, 2
01
0
Sep
10
, 20
10
Sep
13
, 20
10
Sep
16
, 20
10
Sep
19
, 20
10
Sep
22
, 20
10
Sep
25
, 20
10
Sep
28
, 20
10
Average Daily RH / 10
Daily Rainfall
Max Temp
Min Temp
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
May
1, 2
01
1
May
4, 2
01
1
May
7, 2
01
1
May
10
, 20
11
May
13
, 20
11
May
16
, 20
11
May
19
, 20
11
May
22
, 20
11
May
25
, 20
11
May
28
, 20
11
May
31
, 20
11
Jun
3, 2
01
1
Jun
6, 2
01
1
Jun
9, 2
01
1
Jun
12
, 20
11
Jun
15
, 20
11
Jun
18
, 20
11
Jun
21
, 20
11
Jun
24
, 20
11
Jun
27
, 20
11
Jun
30
, 20
11
Jul 3
, 20
11
Jul 6
, 20
11
Jul 9
, 20
11
Jul 1
2, 2
01
1
Jul 1
5, 2
01
1
Jul 1
8, 2
01
1
Jul 2
1, 2
01
1
Jul 2
4, 2
01
1
Jul 2
7, 2
01
1
Jul 3
0, 2
01
1
Au
g 2
, 20
11
Au
g 5
, 20
11
Au
g 8
, 20
11
Au
g 1
1, 2
01
1
Au
g 1
4, 2
01
1
Au
g 1
7, 2
01
1
Au
g 2
0, 2
01
1
Au
g 2
3, 2
01
1
Au
g 2
6, 2
01
1
Au
g 2
9, 2
01
1
Sep
1, 2
01
1
Sep
4, 2
01
1
Sep
7, 2
01
1
Sep
10
, 20
11
Sep
13
, 20
11
Sep
16
, 20
11
Sep
19
, 20
11
Sep
22
, 20
11
Sep
25
, 20
11
Sep
28
, 20
11
Average Daily RH /10
Daily Rainfall
Max Temp
Min Temp
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
May
1, 2
01
2
May
4, 2
01
2
May
7, 2
01
2
May
10
, 20
12
May
13
, 20
12
May
16
, 20
12
May
19
, 20
12
May
22
, 20
12
May
25
, 20
12
May
28
, 20
12
May
31
, 20
12
Jun
3, 2
01
2
Jun
6, 2
01
2
Jun
9, 2
01
2
Jun
12
, 20
12
Jun
15
, 20
12
Jun
18
, 20
12
Jun
21
, 20
12
Jun
24
, 20
12
Jun
27
, 20
12
Jun
30
, 20
12
Jul 3
, 20
12
Jul 6
, 20
12
Jul 9
, 20
12
Jul 1
2, 2
01
2
Jul 1
5, 2
01
2
Jul 1
8, 2
01
2
Jul 2
1, 2
01
2
Jul 2
4, 2
01
2
Jul 2
7, 2
01
2
Jul 3
0, 2
01
2
Au
g 2
, 20
12
Au
g 5
, 20
12
Au
g 8
, 20
12
Au
g 1
1, 2
01
2
Au
g 1
4, 2
01
2
Au
g 1
7, 2
01
2
Au
g 2
0, 2
01
2
Au
g 2
3, 2
01
2
Au
g 2
6, 2
01
2
Au
g 2
9, 2
01
2
Sep
1, 2
01
2
Sep
4, 2
01
2
Sep
7, 2
01
2
Sep
10
, 20
12
Sep
13
, 20
12
Sep
16
, 20
12
Sep
19
, 20
12
Sep
22
, 20
12
Sep
25
, 20
12
Sep
28
, 20
12
Average Daily RH /10
Daily Rainfall
Max Temp
Min Temp
Non-GM Desiree
GM Desiree carrying Rpi-vnt1
Each tuber pile harvested
from 16 plants
Yield results (2012 trial plots)
Yield results (2012 trial plots)
0
2
4
6
8
10
12
14
1 2 3 4 5 6kg
Plot number Desire/Rpi-vnt1.1
Desiree
Plants arranged in 6 plots, each plot
containing 2 block of 16 GM plants
and 1 block of 16 non-GM plants
Acknowledgements
Jonathan Jones Edwin van der Vossen
Mathieu Pel
Tae-Ho Park
Zhaohui Chu
Jadwiga Sliwka
Gianinna Brigneti
Diederik Smilde
Walter Verweij Matthew Smoker
Kamil Witek Jodie Pike
Florian Jupe Sara Perkins
Justine Campling
Field trial Q&A http://www.tsl.ac.uk/lateblightqa.html
Video (making GM potatoes) http://www.youtube.com/user/SainsburyLab
www.tsl.ac.uk