Challenges, Progress & State-of-art in Breeding for Iron/Zinc

First Global Conference on BiofortificationNovember 9-11, 2010, Washington, DC

Merideth BonierbaleInternational Potato Center

Wolfgang Pfeiffer HarvestPlus

HarvestPlus Crop Leaders

3.5 billion people in the developing world are Fe deficient Women and children are most affected

Micronutrient Deficiencies ”Hidden Hunger”

http://www.micronutrient.org

Prevalence of IDA among children <5 years old• Maternal mortality

• Impaired mental development & capacity for labor

• Growth failure• Susceptibility to

infections

Outline

• Genetic Variation in Crop Gene pools

• Setting Breeding Targets• Genetic Gains Achieved• Molecular and Biotechnologies• Product Delivery• Research Needs

Genetic Variation in Crop Gene pools:Varieties, Landraces,

Breeding Populations, Wild Relatives

Qualitative (HPLC)

Semi-Quantitative

NIRS

XRF Bench-topHand-held

Colorimetric

Image-Analyzer

Near-InfraredReflectance

Spectroscopy

X-Ray

Year 20102005

Samplesday-1

1000

500

$US Costsample-1

0.25

1.00(0.5 - 3.0)

• High-throughput• Fast & economical• No contamination

> 305-10

e.g. Worldwide NIRS Quality Network for Sweetpotato (and other crops)

Progress: Fe Variation Discovered in Germplasm of 8 Staple Crops (ppm DW)

Wheat

Sweetpotato

Rice_unpolish

Rice_polish

Potato_Native

Potato_Adv

Maize

Cassava

6050403020100

Wheat

Sweetpotato

Rice_unpolish

Rice_polish

Potato_Native

Potato_Adv

Maize

Cassava

1501401301201101009080706050403020100

Beans

Pearl millet

Wheat

Sweetpotato

Rice_unpolish

Rice_polish

Potato_Native

Potato_Adv

Maize

Cassava

Beans

1101009080706050403020100

Pearl millet

Progress: Zn Variation Discovered in Germplasm of 8 Staple Crops (ppm DW)

BeansPearl MilletPolished_RicePotato_AdvPotato_NativeSweetpotatoUnpolished_RiceWheat

Fe vs Zn

Ord Crops N Correlation Coefficients

1 Pearl Millet 79 0.86

2 Sweetpotato 89 0.85

3 Unpolished_Rice 110 0.79

4 Wheat 176 0.64

5 Beans 215 0.63

6 Potato_Native 604 0.52

7 Polished_Rice 123 0.41

8 Potato_Adv 310 0.31

FEDW

ZnDW

160140120100806040200

120

100

80

60

40

20

0

Positive correlation between Fe & Zn allows simultaneous improvement for both

The amount of Fe or Zn required in a biofortified crop for significant impact on nutritional status

Breeding Target

• ‘Baseline’ = amount obtained from varieties consumed bytarget population

+• ‘Increment’ = amount to be added by

breeding

=

Consumption level (g/day)

Increment of nutrient required for health impact

Concentration of nutrient in the

crop as consumed (after storage, milling &

cooking )

Bioavailability of nutrient in

the diet

Target Nutrient

Content of Staple Foods

Influencial Factors

Primary Sources of Food for Populations at Risk of Malnutrition

Intak

e in g

rams

genYa

msPo

tato

Cassa

vaOFS

P

Cowpe

aLe

ntil

Bean

Maize

WheatRice

Pearl

Mil le

tBa

rley

Sorgh

um

500

400

300

200

100

0

Grains(100% DM)

Legumes(100% DM)

Roots (33% DM)

Tubers(25-33% DM)

Intak

e in g

rams

genYa

msPo

tato

Cassa

vaOFS

P

Cowpe

aLe

ntil

Bean

Maize

WheatRice

Pearl

Mil le

tBa

rley

Sorgh

um

500

400

300

200

100

0

Grains(100% DM)

Legumes(100% DM)

Roots (33% DM)

Tubers(25-33% DM)

Consumption Levels of 13 Staple Food Crops

(DW) (DW) (FW) (FW)

Targeting Food & Production Systems

High Zn Wheat Targets in India

ME1: Temperate Irrigated High Production

ME5: Irrigated High Temperate Stress

42

38

46

36

22

19

12

11

12

14

9

8

6

4

9

8

4

2

3

2

4

7

5

18

0 10 20 30 40 50 60 70 80 90 100

Women

Children

Women

Children

Ab

un

dan

ce

Sca

rcit

y

Cereals Potato Vegetables and fruitsPulses Noodles Food fron social programsBread and cookies Sugars Meat and chickenOther

Dietary Sources of Fe in Huancavelica, Peru

0

20

40

60

80

100

120

140

Pearl Millet Bean Bean Rice Rice Maiz Maiz Wheat Wheat Potato Sweetpotato

Fe Fe Zn Fe Zn Fe Zn Fe Zn Fe Fe

ppm

Baseline & Target Levels for 7 Crops

8

44

88

32

64

8

11

22 22

Non-BiofortifiedAvg. Baseline

BreedingTarget

Genetic Variation Discovered

30 TargetIncrement

Breeding Focus by Crop and Micronutrient

HarvestPlus investment level I. Zn Rice, Zn WheatII. Fe Pearl Millet, Fe BeanIII. Fe Potato, Fe Sorghum,

Fe Lentil. Zn Maize – initially

HarvestPlus, then AgroSalud

Fe & Zn Sweetpotato in SASHA

Fe (ppm)

P (ppm)

Rice polished

MaizeWheat

Bean

Cassava

Potato

Lentil

Pearl Millet

Yams

Phytate: Inhibitor of Fe Absorption

5%

SweetPotato10%

Iron Bioavailability in Landrace Potatoes

0

10

20

30

40

50

60

704393 703168 705543 702464 700234 700787 701997 703274 703488Caco

2 c

ells

ferr

itin

form

atio

n (n

g fe

rriti

n / m

g pr

otei

n)

Caco-2 Cell Ferritin Formation

USDA/SRS & CIP

0,0

5,0

10,0

15,0

20,0

25,0

30,0

15,5 23,3 31,1 38,8 46,6 54,4 62,1 69,9 77,7 85,4 93,2

mg Ac Ascorbico/ 100g DW

Porc

etaj

e de

pob

laci

ón

Base Population

k = 5%

Progeny of selected individuals

mg Vitamin C/ 100g

Perc

ent

Genetic Gains from SelectionGs = k * δp * H2

Selection Intensity

HeritabilityGenetic Variation

Non-negotiable Core Traits

Product Attributes - Breeding Objectives

Fe Zn

FV N=89

PBFN=64

FV N=89

PBFN=64

Genetic Gains for Fe and Zn in OFSPAfrican farmers’ varieties (FV) vs. Pre-breeding families (PBF

(ppm

in d

ry m

atte

r)

Cycle 1 Families: Source of superior clones

Selected genotypes with high micronutrient concentration

Fe (

mg/

kg)

32.0

31.0

30.0

29.0

28.0

27.0

26.0

25.0

24.0

23.0

22.0

21.0

20.0

19.0

18.0

17.0

16.5

16.0

15.0

14.0

12.5

12.0

11.09.0

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

45

40

35

30

25

20

15

10

5

Boxplot Ranges of Fe (mg/kg) in diploid potato families (NCD-II)

Base line(17.5 mg/kg

Biotechnologies

– Reduce time and cost to meet breeding goals

– Exceed levels feasible by conventional breeding

Identification of genes affecting variation in Fe & Zn in Bean by QTL analysis

• Overlapping Fe and Zn QTL suggest common transcriptional control of uptake

• Identification of allelic variation for FRO to facilitate transfer of high mineral traits among genepools and varieties

Blair et al., 2010

Promoter Genomic Wheat Ferritin clone

1DX5 Glutenin Nos

AB

C

• Introduce extra copies of the most active wheat allele of the TaFer1 gene into wheat.

• Biolistic transformation using glutenine1Dx5 promoter to drive endosperm specific expression.

Transgenic WT- Bob white

Prussian blue stain

Targeting Ferritin to the Wheat Endosperm

Exon Intron

(Aarhus University/Denmark)

Research Agreements & Contracts with 7 Private Companies - # will increase

• GxE Performance Testing

• Joint Development of Fe/Zn-denseHybrids (private NARS) & OPVs (public NARS) by Consortium PartnersPartners in Deployment

Variation for Fe in Inbred lines & Hybrids

Product Delivery: Case of Pearl Millet

Breeding cycles

Iron

(ppm

)

2005 2007 2009 2011

50

65

80

100

Lines in release process

Families in pipeline

2010

Baseline

Target

Incremental gains toward breeding goal for Fe in Bean

Wolfgang H PFEIFFER

Product Development & Release Schedule

What Do We Have in Hand to Succeed in Biofortification ?

Micronutrient-enrichment traits are available within the genomes of staple food crops.

Target levels have been defined. Breeding schemes established. First-ever genetic gains for mineral traits

realized Mainstreamed into adapted populations. Product pipelines defined. Partners engaged Early-stage efficacy trials: looking good!