Presentation by Andrew Westby, Director, Natural Resources Institute (University of Greenwich) at the launch event of the Global Panel's Biofortification Policy Brief. Held at the All Party Parliamentary Group All-Party Parliamentary Group on Agriculture and Food for Development on 2 February 2015

1. Scientific opportunities and challenges of bio-fortification
- focus on iron and zinc -
• Staple crops have been bred for yield, not for nutritional quality
• The starch content is increased, diluting iron and zinc

2. Active mobilization of
minerals from the soil
Transport
Storage of minerals in
seeds for the seedling
upon germination
Use of metals for:
enzyme catalysis (Fe, Zn)
or protein structure (Zn)
JannekeBalk2015

3. Estimated number of genes
for ‘handling’ iron and zinc
~10 genes
> 30 for inserting metals
> 50 transporters
> 5 for chelators
> 5 for uptake
> 10 for chelators
Active mobilization of
minerals from the soil
Transport
Storage of minerals in
seeds for the seedling
upon germination
Use of metals for:
enzyme catalysis (Fe, Zn)
or protein structure (Zn)
JannekeBalk2015

4. Natural variation in iron and zinc levels is limited by homeostasis
• wheat 27.8 – 42.5 mg/kg iron = 1.5-fold difference (Zhao et al 2009 J Cereal Sci)
• rice 6.3 – 24.4 mg/kg iron = 3.9-fold difference (Gregorio GB 2002, review)

5. Natural variation in iron and zinc levels is limited by homeostasis
• wheat 27.8 – 42.5 mg/kg iron = 1.5-fold difference (Zhao et al 2009 J Cereal Sci)
• rice 6.3 – 24.4 mg/kg iron = 3.9-fold difference (Gregorio GB 2002, review)
The iron and zinc content varies in different parts of the plant
and in different plant species
Iron Zinc (mg/kg)
Lentils 111 39
Beans (blackeye) 59 32
Spinach 21 7
Broccoli 17 6
Potatoes 3 2
(McCance and Widdowsons, Food Standard Agency 2002)
Uneven distribution of zinc
in barley (in pink, by D Podar)

6. Natural variation in iron and zinc levels is limited by homeostasis
• wheat 27.8 – 42.5 mg/kg iron = 1.5-fold difference (Zhao et al 2009 J Cereal Sci)
• rice 6.3 – 24.4 mg/kg iron = 3.9-fold difference (Gregorio GB 2002, review)
GM ‘proof-of-principle’ studies demonstrate 4-fold increase in
iron and zinc in rice (Bashir et al 2013 Front Plant Sci 4:15, review)
The iron and zinc content varies in different parts of the plant
and in different plant species
Iron Zinc (mg/kg)
Lentils 111 39
Beans (blackeye) 59 32
Spinach 21 7
Broccoli 17 6
Potatoes 3 2
(McCance and Widdowsons, Food Standard Agency 2002)
Uneven distribution of zinc
in barley (in pink, by D Podar)

7. Note: total iron values do not represent bio-available iron !
BBSRC-DRINC2 project 2014 – 2017
“Speciation and bioavailability of iron in plant foods”
Bloodstream
Gut cells
Digested food with a mix of iron species

8. • Confirm function of a crop gene in a model organism
• Identify crop plants with genetic variation in that gene
• Test and confirm altered traits in selected crop plants
• Introduce in commercial lines
HarvestPlus funding to JIC for “High Iron Wheat”
Modern genetics: We can induce genetic variation (non-GM),
and speed up breeding with knowledge of the genome sequence

9. Opportunities Challenges
Molecular pathways for vitamin
biosynthesis and micronutrient
uptake have mostly been identified
Genomes of many crops have been
sequenced, enabling faster breeding
New methods to induce and select
genetic variation for desired traits
There are still basic gaps in our
knowledge, e.g. iron sensor in plants
Traits such as iron content are difficult
to change, because plants have
evolved to maintain homeostasis
New crop varieties (e.g. wheat) still
take 10 – 15 years to the market
Janneke Balk, John Innes Centre, 2015
Need for sustained funding