Fast-track breeding of high-yielding varieties of Artemisia annua by dfsiopmhy6

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									     Fast-track breeding of high-yielding
        varieties of Artemisia annua
                       David Clayton
Centre for Novel Agricultural Products, University of York, UK
          Aims of the CNAP Artemisia Research Project

     •   to identify plants of A. annua with increased yields of artemisinin.
     •   to field trial plants, confirm heritability of high yield trait and select the
         best lines
     •   to develop robust and stable high yield
         varieties which will slot into the current
         supply chain for ACTs
     •   to deliver high-yielding seed to the ACT
         supply chain in as short a timeframe as
         possible
     •   to reduce the cost of ACTs




Tackling malaria with fast-track plant breeding
                                        Scientific strategy
       induced variation                            natural variation



      forward (trait)               reverse            marker assisted breeding
         screen                 (genetic) screen



       identify individuals with high artemisinin yield




                             develop robust
                              new varieties

Tackling malaria with fast-track plant breeding
                                         Starting material


             • Artemis - developed by Mediplant and currently used
                commercially. Yielding from 0.6 to 1.2% depending on
                the location

             • collection of other varieties from various locations
                including Vietnam and East Africa




Tackling malaria with fast-track plant breeding
                           Summary of Breeding Routes

          Route 1: Forward Screen
          Route 2: Natural variation from the Artemis gene pool
          Route 3: QTL analysis of Artemis
          Route 4: Use of natural populations
          Route 5: Association study of natural variation
          Route 6: Heteroduplex mapping
          Route 7: Combining traits                         Induced variation
                                                            Natural variation




Tackling malaria with fast-track plant breeding
                                                        Delivery timeline
     % Artemisinin / unit dry weight




                                       6
                                                                                  Phase 3
                                                                                  Route 7
                                       5
                                                                     Phase 2
                                       4                            Routes 3b-6

                                       3
                                                     Phase 1
                                                  Routes 1,2 & 3a
                                       2

                                       1


                                           2008       2011          2012-2013     2014-2015

Tackling malaria with fast-track plant breeding
                                        Scientific strategy
       induced variation                            natural variation



      forward (trait)               reverse            marker assisted breeding
         screen                 (genetic) screen



       identify individuals with high artemisinin yield




                             develop robust
                              new varieties

Tackling malaria with fast-track plant breeding
                         Route 1: Forward (trait) Screen


 •    high throughput screen of M2 (selfed)
      plants for artemisinin yield
       – Chloroform dip
       – UPLC MS with 2.5 min run time

 •    identify high yielding individuals and
      confirm trait in the field                  RT: 0.00 - 2.50

                                                                     100


                                                                      95
                                                                                                                                                                    1.05


                                                                                                                                                                                  Artemis inin
                                                                                                                                                                                  C 15 H 22 O 5
                                                                      90
                                                                                                                                                                                  Mw =  282.2
                                                                      85


                                                                      80




 •    ~1000 plants screened every two / three
                                                                      75


                                                                      70


                                                                      65


                                                                      60




      weeks.
                                                   R la eA u d n e
                                                    e tiv b n a c
                                                                      55


                                                                      50


                                                                      45                                                                          0.84


                                                                      40


                                                                      35


                                                                      30


                                                                      25                                                          0.68
                                                                                                                                           0.80
                                                                      20                                                                                                                   1.33
                                                                                                      0.41
                                                                      15                                                                                                            1.25
                                                                                                                                         0.78
                                                                                                                           0.62
                                                                                                                                                                                                  1.36
                                                                      10
                                                                                                                                                         0.91              1.11
                                                                                                                                                                                                                         1.70 1.72 1.79
                                                                                                                                                             1.00                                          1.53   1.62
                                                                                                             0.44                                                                                   1.44                                  1.87
                                                                       5                                                                                                                                                                          1.97   2.16   2.23   2.34 2.36
                                                                                 0.11                               0.51
                                                                                        0.13   0.30
                                                                       0
                                                                           0.0           0.2          0.4                  0.6                  0.8           1.0             1.2                 1.4             1.6          1.8               2.0        2.2            2.4
                                                                                                                                                                              Tim e (m in)




Tackling malaria with fast-track plant breeding
                                 Forward Screen Update
                       •    screened 21 000 / 25 000 plants
                       •    identified 230 high yield individuals
                            (between 1.5 and 3 fold higher than Artemis)


                                                                   Distribution of Forward screen Batch 9
                                                                  120


                                                                  100


                                                                  80




                                                      Frequency
                                                                  60


                                                                  40


                                                                  20


                                                                   0
                                                                        0   8     16      24    32     40   48
                                                                             Artemisinin ug/mg dry weight




Tackling malaria with fast-track plant breeding
                                  Forward Screen Status


                                                  230

                        130                                               100+
                Experimental Trials                                 Experimental Trials
                      2008                                                2009

            •   experimental trials will characterise
                   –   metabolite content
                   –   trichome density
                   –   biomass traits (height, fresh weight, leaf area, nodes)
                   –   vegetative stage
                   –   plant architecture
                to determine field performance and establish basis of high yield trait

Tackling malaria with fast-track plant breeding
                                            Project status
            •   multiple lines exhibiting increased yield in artemisinin
                identified using a forward screen.
            •   first heritability data suggests a significant proportion of
                these are due to genotype
            •   mapping populations established in 3 different
                environments and genetic map constructed.
            •   mutations in target genes identified with potential to
                increase yield of artemisinin




Tackling malaria with fast-track plant breeding
                               EARLIEST DELIVERY - 2011
  Minimum target yield improvement is double the yield of Artemis


                              Potential yield improvement from Phase 1 routes
                           already known ~ 2-4% artemisinin per unit dry weight




    2007                   2008                        2009                         2010                       2011              2012


             Potential High Yielder                                   Hybrid seed for                                 Earliest date
                 identification                                         field trials                                   to market
                                  Heritability testing/Backcrossing


                                                        Experimental Field Trials
             Potential yield known
                                                                                           Commercial Field Trials



                                                                                           True yield known



Tackling malaria with fast-track plant breeding
            Acknowledgements – Artemisia Research Project




      The CNAP Artemisia Research Project is funded by The Bill & Melinda Gates Foundation.
      Initial work was financed by Medicines for Malaria Venture, GlaxoSmithKline and the Garfield Weston Foundation


     • Ian Graham    • Anne Rae        • Elspeth Bartlet
     • Dianna Bowles • Debs Rathbone • Wendy Lawley
                     • Thilo Winzer    • Caroline Calvert
                     • Tony Larson
                                                                                Department of Biology
                     • Yi Li
                     • Godfree Chigeza

Tackling malaria with fast-track plant breeding

								
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