Transcript Can breeders shift from a focus on improved crop efficiency to

How can Genetics help
to deliver
sustainability?
Prof David Pink
Can breeders shift from a focus on
Improved crop efficiency - Increase marketable
yield/unit area (under high input conditions)
to
Improved sustainability - Retain/improve marketable
yield/unit area with reduced inputs e.g.
• Pesticides
• Resources – water, fertiliser
If they can why should they?
Unsustainable breeding for resistance
e.g. Lettuce Downy Mildew
Caused by oomycete
Bremia lactucae

Most important
lettuce disease worldwide

> 30 ‘broken’ Dm genes

Unsustainable breeding for resistance – the
accelerated ‘Boom-Bust’ cycle
Collaboration
to identify new
‘major gene’
for resistance
Quicker BUSTNew pathotype –
Dm gene ‘wasted’
Higher selection
pressure against
avirulence
More rapid BOOMDeployment in
many new varieties
simultaneously
from several
breeding companies
An sustainable form of Resistance
Field Resistance
•Effective against all
races
•Rate reducing (partial)
resistance
•Less plants infected
•Fewer leaves infected
•Smaller lesions/less
sporulation.
•Can breed for this using
molecular markers – beat
the breeder
cv Iceberg
Breeding for Pest and Disease
Resistance
Need to shift focus to resistance of the
crop not the plant
Crop resistance = economically acceptable
level of disease/pest
Achieved by a combination of methods that
each reduce the level of infection i.e.
integrated crop management of which
partial resistance is one component
What are targets for breeding for
sustainable production?
Use life cycle analysis of current production
methods to identify which components have biggest
environmental impact and/or energy demand to
identify targets for breeders.
e.g. NIAB study of OSR production
in UK – 83% of energy input into
growing crop is associated with
manufacture (70%)and
application (13%)of nitrogen
fertiliser.
Genetic variation for Response to N levels in
Brassica napus diversity set
Ratio average dry weight at high vs low N
1.8
1.6
1.4
Ratio
1.2
1
0.8
0.6
0.4
0.2
Line no.
Graham Teakle
26
90
67
58
57
1
63
30
7
84
25
31
89
29
86
35
77
10
72
21
97
45
69
42
2
75
0
For vegetables breeding for improved post
harvest may also improve LCA of the
product by:
•
Reduced need for energy in cooling
•
Reduced wastage
Exploiting genetic variation in Phosphorous use efficiency
B. oleracea diversity set
100
Low P (Index 2)
High P (Index 4)
Frequency
75
Brassica with low PAUE
Non P-responsive
Low internal P-use efficiency
Smaller shoots
Shorter roots
Less root FW
John Hammond
50
25
0
0
200
400
600
800
1000 1200 1400 1600
PUE (g2 biomass g-1 P in plant)
Brassica with high PAUE
P-responsive
High internal P-use efficiency
Larger shoots
Longer roots
Greater root FW
GLOBAL CLIMATE CHANGE:
change in summer rainfall under two scenarios of CO2
emissions
2020
2050
Summer rainfall
% change
2080
Low emissions
+10
0
-10
-20
-30
-40
-50
High emissions
(not in 2007!!)
[From: UKCIP02 report]
Regions of Brassica oleracea genome associated with water use efficiency
O1
Andrew Thompson
O2
O3
O4
O5
O6
O7
O8
d18O Gleadthorpe
d18O Kirton
d13C Gleadthorpe
d13C Kirton
SPAD Gleadthorpe
SPAD Kirton
Specific leaf area Gleadthorpe
Specific leaf area Kirton
Biomass response Kirton
O9
Mean
Drought
Control
Can breeders shift from a focus on improved crop
efficiency to improved sustainability? – YES
•Genetic variation for key traits for sustainable
production exists
•The tools to breed more sustainable crops are being
developed.
Using natural genetic variation breeders can breed
crops that can use or acquire resources (water and
nutrients) more efficiently. This will reduce these
inputs into agricultural systems, providing economic
and environmental benefits
why should they?
Breeders need to be incentivised/rewarded
to produce varieties for low input
production.
Current Defra- funded project
investigating how to assess variety traits
which are important for performance under
low input systems.
-will also provide breeders with information
on target traits
Acknowledgements
Graham Teakle – NUE
John Hammond – PUE
Andrew Thompson - WUE