1. Challenges for Improving Wheat Quality
Peter Shewry
(Rothamsted Research and the University of Reading)

2. The major grain components determine end use quality
distilling
biofuels
livestock
feed
starch
milling
feed
other
seed
UK usage of wheat 2013
Total= 14 m tonnes
gluten
proteins
food
processing
cell walls (fibre)
vitamins minerals
phytochemicals
Human health

3. Challenges for Wheat Quality in Europe
Reduce N requirement for growing high yielding bread making wheats
Increase STABILITY of yield and quality
Improve health benefits

4. The high grain protein requirement for bread making results in N applications above the optimum for yield
N application (kg/Ha)
cost of N fertiliser

5. Improved quality with reduced N
Exploit grain protein deviation (GPD)
Improve quality at low protein
Exploit non-protein sources of quality

6. Grain protein deviation (GPD):
Mean grain N contents and yields for 47 wheat cultivars grown at Rothamsted Research between 2004 and 2012.

7. Exploiting GPD: project components
Six cultivars
WITH GPD
Hereward: Group 1, stable high protein
Cordiale: Group 2, medium protein,
Marksman: Group 2, medium protein,
WITHOUT GPD
Xi 19: Group 1, medium protein
Malacca: Group 1, medium protein
Istabraq: Group 4, low protein, suitable for feed and biofuel
Trials
11 environments (sites or years)
Analyses
Yield
Grain protein
Milling and baking
Transcriptomics (21 dpa)

9. Expression of 8770 genes varied with variety-and/or environment
Transcriptomics CO He IS
2011
2009 and 2010 Ma MK XI
Expression of 8770 genes varied with variety-and/or environment
(out of total) Xi Co
Expression data processed to remove effects of
Nitrogen fertilisation
Yield
Identified 136 transcripts related to cultivar differences in GPD

10. The challenge is to confirm gene function genetic analysis
Expression of genes positively related to GDP in 2009 (open circles), 2010 (closed circles) and 2011 (open squares)
The samples are sorted along the x-axis according to the cultivar
With GPD
Red: Hereward
Green: Cordiale
Yellow: Marksman
Without GPD
Blue: Istabraq
Black: Malacca
Purple: Xi19
The challenge is to confirm gene function
genetic analysis
transgenesis

11. Can we identify new sources of improved and STABLE quality?
Lipids by MS/MS
LMW metabolites by NMR and ESI-MS

12. The role of lipids in determining gas bubble stability in wheat dough
Formation of visco-elastic gluten network during mixing
Expansion of the network by entrapment of CO2 during proofing
Retention of gas bubble structure through to baking
These are determined by:
Gluten viscoelasticity
Lipids at the gas bubble interface

13. Surface active lipids can be studied in dough liquor
Centrifuge
dough
Foam micro-conductivity to measure stability.
Over -foaming to separation and collect active lipids.
Foam stability
Foam
Electrode
Jet
Surface composition and structure
Surface tension
& surface rheology
Dough liquor
Dough liquor
zoom
microscope
digital
camera
Pendant drop
Langmuir trough allows sampling of surface lipids for MS analysis

14. Lipidomics Extraction MS analysis Data Processing
Direct infusion:
CTC PAL
MS/MS
4000 QTRAP
Separates, identifies and and quantifies over150 molecular species

15. Lipids in Foaming of dough liquor

16. Comparison of phospholipids in flour and dough liquor of cv Hereward
Will allow
Selection of improved lines
Innovative milling to concentrate lipids

17. High stable quality at lower N can be achieved by combining
Exploit GPD
High dough strength at lower protein
Novel non-protein sources of quality
This will be facilitated by new technologies

18. Improving wheat quality for diet and health- major components in grain
Dietary fibre
Minerals (Fe, Zn, Se)
B vitamins (folates)
Methyl donors (betaine)

19. Fibre is deficient in EU diets UK intake 14g/day
Bread contributes significantly to the daily intake of dietary fibre in the UK (% adult intake)
Energy
Protein
Carbohydrate
Fibre
All bread 13 12 21 20
White bread 8 14 11
Wholemeal
Bread 2 3 5
Fibre is deficient in EU diets
UK intake 14g/day
EFSA recommended 25g/day
Source: Steer et al. Proc Nutr Soc/ 2008, 67, E363.

20. Some potential mechanisms for benefits of DF
Decreased transit time
Increased stool bulk
Improved bowel function
Reduce absorption
Fermentation in colon to short chain fatty acids
Reduce cholesterol
Slow digestion and absorption due to increased viscosity
Inhibit amylase and absorption of sugars
Slow glucose absorption, improve insulin sensitivity
Beneficial effects of butyric acid on colonocytes
Dilute and reduced exposure to carcinogens
Reduce colorectal cancer
Based on slide provided by Janet Cade, Leeds

21. Some take home messages from meta-analyses of fibre and health
10% reduction in risk of colon cancer with10g/day extra cereal/wholegrain fibre
5% reduction in risk of breast cancer with 10g/day extra soluble fibre
7% reduction in risk of stroke with 7g/day extra total fibre
Thanks to Janet Cade, University of Leeds

22. Aims: identify variation determine heritability
Diversity screen of 150 bread wheat lines and 50 other cereals grown at Martonvasar in 2004/5
Types
Land races and old variety populations 14
Old and transitional varieties
Modern varieties
Germplasm accessions
Winter type
Spring type
Geographical origins
Western Europe
France, UK, Netherlands
West-Central Europe
Germany, Austria, Switzerland, Czech Republic,Poland 22
South Europe
Italy, Bulgaria, Serbia, Croatia 28
South Continental Europe
Hungary, Romania 14
Steppe
Russia, Ukraine 13
Americas
USA, Canada, Mexico, Argentina 30
Asia, Near East, Australia
China, Korea, Australia, Turkey 15 l
Glasshouse/field
Spelt
durum wheat
T. monococcum
T. dicoccum
Rye
Barley
Oats
Aims: identify variation
determine heritability

23. Arabinoxylan (AX) is the major dietary fibre component in wheat grain
White flour
2-3% fibre
70% AX
Bran
45-50 % fibre
50% AX

24. The contents of soluble and total AX fibre vary widely in bran and white flour of 150 wheat lines
Yumai 34
SOLUBLE: %
SOLUBLE: %
Yumai 34
% SOLUBLE: 2-5%
% SOLUBLE: 20-50%
Data of Kurt Gebruers, Christophe Courtin and Jan Delcour (KU Leuven)

25. AX content of flour and bran is highly heritable

26. Exploiting natural variation in AX fibre: Yumai 34
Healthgrain Diversity screen data from Gebruers et al (2008) J. Ag. Food Chem., 56,
A Chinese wheat variety released in 1998 in Henan province
High fibre content (total and soluble)
High viscosity of aqueous extracts
Good breadmaking quality
Yumai 34
Control

27. Exploiting natural variation in AX fibre:
Yumai 34 x Ukrainka AX
content
Relative
viscosity
96 F6 lines + parents
Fibre analysis
Genotyping
Transcriptome analysis
of bulk segregants

28. New sources of variation: the Watkins collection
Collected by Board of Trade for A E Watkins (University of Cambridge)
From markets and farms in1920s and 30s
Initially several thousand but now down to1300
From 34 countries
Held at JIC
Core collection 119 lines

29. Total and WE-AX in wholemeal flours of the Watkins lines
TOT-AX
Yumai 34
WE-AX as % of TOT-AX
40%
Yumai 34 0%

30. Exploring the role of AX fibre in the human GI tract
effects of AX on digestion, viscosity and mass transfer
SMALL
INTESTINE
prebiotic effects of AX: SCFAs, “good bacteria”
ferulate and vascular function/blood pressure
dough fermentation and IBS
COLON

31. Conclusions- Priorities
Develop N efficient wheat with good quality at low grain N
New protein and non-protein sources of quality- greater stability?
Improve health benefits
DF is an important target with established health benefits and high heritability

32. Thanks DIETARY FIBRE Rowan Mitchell Alison Lovegrove GPD
Mark Wilkinson
Till Pellny
Jackie Freeman
Ondrej Kosik
Zoltan Bedo (MTA)
Mariann Rakszegi (MTA)
GRAIN LIPIDS
Richard Haslam (RRes)
Peter Wilde (IFR)
Louise Salt (IFR)
Irene Gonzalez-Thuillier
Paola Tosi (Reading)
Simon Penson (Campden BRI)
Peter Skeggs (Hovis)
GPD
Malcolm Hawkesford
Yongfang Wan
Gemma Chope (Campden BRI)
Simon Penson (Campden BRI)
Ellen Mosleth Faergestad (Nofima/Oslo)
Millers and bakers
Breeders