Elisa Salas Murrugarra WPC ALAP CUSCO, PERU 2018

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2 POTATO BIOFORTIFICATION INTRODUCTION OF GENETIC GAINS FOR IRON&ZINC CONCENTRATION from a Diploid population to advanced disease resistant tetraploid potatoes Elisa Salas Murrugarra International Potato Center (CIP). Germplasm Enhancement and Crop Improvement-Crop Management Division Av. La Molina La Molina. Lima 12. Peru Corresponding author s e.salas@cgiar.org

3 Introduction Micronutrient Deficiencies Hidden Hunger Maternal mortality Mental development and learning Physical labor Stunting Susceptibility to infections Women of reproductive age Rwanda: 59 % Kenya: 24 % Ethiopia: 19 % Peru: >50 % Children under 5 years old Rwanda: 38 % Kenya: 46 % Ethiopia: 50 % Peru: 43 %

4 Anaemia as a public health problem by country Preschool-age children WHO 2008

5 Genetic diversity assessment Genetic Resources and Improved Populations Iron (Fe) Zinc (Zn) Lowland Tropics Virus Resistant (LTVR) Population Vitamin C Carotenoids Phenolics Promoters and Inhibitors of Mineral Absorption Highland Tropics Late Blight Resistant (B3) Population Biofortified Population: High Micronutrient Concentrations

6 Advanced Groups clones Landrace Spp Biofortification: Base Population IRON (mg/k,dw) IRON_DW n=64 Adg n=81 Gon n=195 Phu n=242 IRON_DW Stn FEDW Each symbol represents up to 2 observations n=140 LB n=65 LTVR n=41 LTVR_LB n=30 Var. World FEDW X=

7 2013 Breeding at diploid level Timeline 2005 Breeding for Iron and Zinc in Diploid Potato Base Population and Crosses (2x-2x) - 3 cycles of recurrent selection - Cycle 0: Selected diploid cultivars Stn, Gon, Phu Cycle I: 16 families NCD I (4 male groups) Heritability, selection Cycle II: 32 families NCD II (2 sets 4 x 4) Parental value, selection Cycle II: Selected diploid clones ppm Fe 2010 Cycle III: Crosses Selected clones (n=20) Cycle III: Select diploid clones ppm Fe

8 Development of Base Population at Diploid Level: NCD I Group I X Stn Gon Group II X s s Stn Phu Gon Gon Gon Gon Gon Phu

9 Genetic evaluation of Micronutrient Traits in Diploid base population Parental value: GCA effects for Fe and Zn concentration

10 Frequency Frequency Progress: Fe and Zn contents of potato increased through 3 Cycles of Recurrent Selection at Diploid Level % Genetic Gain for IRON Treatment Cycle 0 Cycle2 Cycle3 Year 2011 : 26 Diploid Clones Selected Cycle II Mean StDev N Fe: ppm Zn: ppm Yield:8-23 t ha Fe mg/kg DW % Genetic Gain for ZINC Treatment Cycle 0 Cycle2 Cycle3 Mean StDev N Year 2015: 34 Diploid Clones Selected Cycle III Fe: ppm Zn=18-32 ppm Yield:9-25 t ha Zn mg/kg DW 30 35

11 Estimates of Gains (%) per Cycles for Iron, Zinc and Yield Components 150 Cycle 2 (M2-Base Population) Cycle 3 (M3-M2) 100 Total (M3-Base Population) Iron Zinc Number of tubers/plant Tuber weight/ plant Average tuber weight Dry matter Vitamin C

12 High-Throughput Methods for Mineral Analysis a) Inductively Coupled Plasma Spectroscopy (ICP) Iron (Fe) o 50 Samples/day o $ 25 / Sample Inductively coupled plasma mass spectrometry Burgos et al The Science of Food and Agriculture.87(4): b) X-ray fluorescence Spectroscopy (XRF) Zinc (Zn) o 300 Samples/day o $ 15 / Samples Fluorescence Spectroscopy (XRF) T. zum Felde et al (Por publicar)

13 Taking advantage of Agroecological Diversity in Peru Selection of clones with resistance to LB under field conditions Soil texture Clay Loam Soil EC (ds/m) 1.49 Soil PH 7.59 Zinc ppm Iron ppm 7.72 Soil texture Soil EC (ds/m) Soil PH 7.6 Zinc ppm 13.2 Iron ppm 2.36 Sandy Clay Loam Soil texture Sandy Loam Soil EC (ds/m) 0.68 Soil PH 4.6 Zinc ppm 2.1 Iron ppm

14 Bioaccessibility of Iron

15 Incorporation of Micronutrients from Diploid into Tetraploid populations (33) Advanced 4x Female Parents (17) Selected 2x Male Parents from Cycle II Disease Resistance Stress tolerant High stable yield Processing quality Tuber appearance Seed 230 families 4x -2x ( genotypes) High level / GCA of Fe & Zn concentration High frequency 2n pollen

16 Ploidy level identification by chloroplast counting in guard cells genotypes Sowing seeds families Transplanting seedlings Transplanting to pots Samples of 3 folioles One or two drops of iodine solution (iodine-potassium iodide) were placed in the center of a slide Peel off the surface cell layer from the undersurface of the leaf. Chloroplast Number in Stomatal Guard Cells

17 Biofortification at Tetraploid Level- Cycle TETRAPLOIDIZATION Crosses 4x - 2x 2013 Ploidy identification ( seedlings) Tuber families 2014 Micronutrient Screening & Field trials genotypes 4500 genotypes Clean copy Clean copy Loc 1-LM 230 masl Loc 2-PAUC 3300 masl Loc masl Disease screening Loc 5-OXA Late blight Loc 6-SR Potato Virus Y genotypes Clean copy Invitro introduction Loc masl Loc masl Clean genotypes copy Loc masl Loc 5-OXA Late blight Loc 1- LM (GH) Late blight & Citometry Analysis Loc 6-SR Potato Virus Y 2018 Intercrossing Start cycle 2 International Distribution for Variety Selection MET s of 30 Biofortified clones in 8 localities of the highland in Peru

18 More than 50 new generation of biofortified tetraploid potato clones adapted to tropical highland and mid-elevation ecologies were selected for international distribution: Buthan, Nepal, Kenya, Malawi, India & Peru High Fe contents (30-45 mg/kg) Zn contents (26-35 mg/kg) Resistance to late blight and/or PVY High yield (from ton/ha) Cusco 2018 Cusco 2018

19 CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP % Selection Top families and parents Parents 4x CIP CIP CIP CIP CIP CIP CIP CIP Parents 2x CIP CIP CIP CIP CIP CIP CIP CIP CIP CIP Traits: Iron & Zinc, yield, tuber appearance Families (4x-2X)