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Towards higher yielding, more water
efficient crops – elements of success
Richard Richards
CSIRO Plant Industry,
Canberra
CSIRO
CSIRO - High Performance Crops for Australia
Better plants for acid soils
Improved salt tolerance
Molecular and physiological germplasm enhancement for dry environments
Wheat varieties for the HRZ
Chromosome engineering in wheat
CSIRO
HRZ – Regions and cereal products
CSIRO
Disease pressure in the HRZ
Bdv2
BYDV
Lr19+
Leaf rust
CSIRO
Chromosome engineering in wheat
Thinopyrum
intermediumThinopyrum
ponticum
7DThinopyrum
intermedium
☺Bdv2 resistance
☺yield boost gene
Thinopyrum
ponticum
☺ Lr19 rust resistance
☺ Sr25 rust resistance
☺ Yield boost gene
� Very yellow flour
Bdv2
BYDV
Lr19+
Leaf rust
CSIRO
Drysdale and Rees
10% yield increase
Australian Hard quality
High Yield
High water use efficiency
Rust resistance
Broad spectrum disease
resistance
05/06 10 fold increase in area sown to DrysdaleLow WUE High WUE
13C 13C12C12C
New selection technologies to improve
water-use efficiency
CSIRO
New selection technologies to improve
water-use efficiency
Improved crop establishment
Currentcultivars
Wasteful tillers
Current cultivars + tin
Fewer wasteful tillersLarger earsLarger grains
Greater shoot and root vigour
Molecular markers
underpin each of
these traits
(UA, GRDC, Breedco’s)
CSIRO
Rht4Rht5
Rht12
Rht1
Rht2
Rht13
tin
TE
Markers for genes contributing to water
use efficiency and yield
root
length
Major gene QTL Abiotic Grain quality Biotic
vigour
coleoptile
CSIRO
Gene and trait discovery to improve salt
tolerance
Two new genes for salt tolerance discovered
Nax1(chromosome 2AL)
Nax2(chomosome 5A)
Both Nax genes are putative
cation transporters:
HKT7 and HKT8 family
T. monococcum donated
Nax genes to landrace
tetraploid
(ACPFG, UA, NSW Ag, GRDC)
CSIRO
Acid soil tolerance in cereals
Single dominant locus confers Al tolerance
Identified and cloned ALMT1
Carazinho tolerance gene in an Egret background
(Okayama Univ, USDA Cornell,
NSW Agriculture)
CSIRO
Soil Biology and improved crop
performance
Challenges
• nutrient
acquisition
• allelopathy
• acid soil
tolerance
• disease
control
Root exudates for:
CSIRO
Designing crops for future environments
and cropping systems
• High rainfall zone cropping
• Crops responsive to changes in climate
Conservation farming systems (stubble retention, direct drilling)
CSIRO
Towards a new yield potential in cereals
District AverageDistrict AverageDistrict AverageDistrict Average
Grain Yield (t ha-1)
In season rainfall (mm)
8
6
4
2
0
50 200100 150 250 300 400350
Current PotentialCurrent PotentialCurrent PotentialCurrent Potential
New PotentialNew PotentialNew PotentialNew Potential
CSIRO
More drought resistance or more crop per drop?
Water productivity
CSIRO
Yield of winter cereals in water-limited
environments
Harvest
Index
xWater-use
Efficiency
xWater
Use
=Grain
Yield
Biomass
(Passioura identity)
CSIRO
But first ……..
• For breeding, patch up other limitations eg:
• Foliar diseases
• Root diseases
• Abiotic limitations such as B, Al
• And get flowering time right
CSIRO
Extended crop duration in wheat
• Advantages in dry environments
• Water-use efficiency can increase by
a factor of 2
• Evaporation from the soil surface is
reduced (more water use by crop)
• early growth is fast because soil and
air temperatures are warmer
• longer duration for root growth
Yield increase (%) with 14 days earlier
sowing
80
90
100
110
120
130
CU87
237
mm
CU88
WH87
CO88
NO88
N87
WH88
NO87
328
mm
Trial sites
Anderson et al
CSIRO
Towards a new yield potential
Reduce water loss from soil surface
Rainfall (mm)
50 100 150 200 250 300 350 400
Grain Yield (t ha-1)
0
2
4
6
8
Current Potential
District average
New Potential
CSIRO
Longer coleoptiles to improve crop
establishment
Often 50% of potential yield is lost due to
evaporation of moisture from the soil surface.
CSIRO
More vigorous early growth
JanzVig 18
CSIRO
High vigour wheats for greater weed competitivenessGrain yield (t/ha)
1.0
1.5
2.0
2.5
3.0
C03 E20 D29 Janz(cv)
Galleon(Barley)
-oats
+oats
Mean grain yield over 3 years with and without weeds
Approximately 3,500 BC and TC high early vigour, semidwarf selections for
evaluation at Roseworthy SA in 2006
CSIRO
Selection for above-ground vigour
CSIRO
Reduction of later formed tillers
Currentcultivars
Wasteful tillers
Current cultivars + tin
Fewer wasteful tillersLarger earsLarger grains
Current cultivars typically produce twice as many tillers as survive.
CSIRO
Shoot traits for an increased rooting zone:
reduced tillering
Days after sowing
10 20 30 40 50 60 70 80
0
500
1000
1500
2000
2500
3000
Banks ++
Banks +
Banks -
Kite +
Kite -
m.m
-2
Root
length
Closed symbols
Open symbols
CSIRO
Do they correlate with field grown roots?
CSIRO
Towards a new yield potential
Increase transpiration efficiency
Rainfall (mm)
50 100 150 200 250 300 350 400
Grain Yield (t ha-1)
0
2
4
6
8
Current Potential
District average
New Potential
CSIRO
We must develop more water-efficient
crops – changing the biochemistry
CSIRO
CSIRO
New selection method for water-use
efficiency - changing the biochemistry
High
Water-use efficiency
Low
Water-use efficiency
Outside leaf
Inside leaf
CSIRO
CSIRO
New water-efficient wheat cultivars
Features
� Australian Hard quality
� High Yield
� High water use efficiency
� Triple Rust resistance
� Broad spectrum disease
resistance
2002, 2003 Release (AWB Seeds)
Drysdale and Rees:
Wheat cultivars selected for dry conditions
10% yield increase Drysdale
Developed using a new
isotope selection method
CSIRO
Grain yield advantage of low 12C/13C
selected lines
Environment mean yield (t.ha-1)
0 2 4 6 8
Grain yield advantage (%)
0
2
4
6
8
10
12
Selection for
low 12C/13C
CSIRO
Chromosome locations/regions for genes contributing
to greater 12C/13C discrimination (Cranbrook/Halberd)
2002 2003 early 20042003 late
► 41 to 82% genetic variance accounted for in each environment
CSIRO
Towards a new yield potential in cereals
District AverageDistrict AverageDistrict AverageDistrict Average
Grain Yield (t ha-1)
In season rainfall (mm)
8
6
4
2
0
50 200100 150 250 300 400350
Current PotentialCurrent PotentialCurrent PotentialCurrent Potential
New PotentialNew PotentialNew PotentialNew Potential
CSIRO
Priorities for winter cereal improvement in a
water-limited environment
• Make use of full growing season
• Reduce evaporation of precious rainfall from soil surface
• Increase water use efficiency
• Increase C allocation to grain
• Increase rooting depth (for better years)
CSIRO
Conclusions
•Passion
•Focus
•Collaboration
•Reality checks
•Serendipity
- the elements of success
CSIRO
Acknowledgements:
Graham Farquhar
Tony Condon
Greg Rebetzke
Michelle Watt
Wolfgang Spielmeyer
Marc Ellis
David Bonnett
Peter Ryan
Manny Delhaize
Phil Larkin
Rana Munns
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