Clair Hershey - PowerPoint PPT Presentation

odessa
clair hershey n.
Skip this Video
Loading SlideShow in 5 Seconds..
Clair Hershey PowerPoint Presentation
Download Presentation
Clair Hershey

play fullscreen
1 / 26
Download Presentation
Clair Hershey
193 Views
Download Presentation

Clair Hershey

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Cassava at CIAT Annual Program Review 2011 Nairobi, Kenya10 May 2011 Clair Hershey

  2. Starches

  3. Waxy cassava starch granules (AM206-5) Hidrolisis Small granule cassava starch (5 G160-13)

  4. Glucose content during Simultaneous Saccharification & Fermentation (SSF) of Very High Gravity (VHG) cassava starch for ethanol production Enzyme: Stargen 2; Genencor

  5. Development of double mutants to generate new starch phenotypes Waxystarch (wxwxSGSG) Small Granule WxWxsgsg X F1 (WxwxSGsg) Self-pollinated or crossed Wx-- SG-- (Normal starch) wxwx SG-- (Waxy starch) Wx -- sgsg (Small granule) wxwxsgsg (Double mutant) 784 S1 and 188 “F2”, transplanted at the end of 2010, will be harvested and tested by the end of 2011

  6. Progress increasing carotenoids content

  7. y = 2.346x + 8.6995 R2 = 0.7763 Progress in total carotenoids content in cassava roots during the last six years of breeding 30 Maximum 25 20 TCC (µg/ g) 15 Average 10 5 Minimum 0 2005 2006 2007 2008 2009 2010 Year

  8. Relevant results from the evaluations made in 2010 Nutritional goal of 15 ug established in 2005 achieved through a rapid cycling scheme

  9. New tools

  10. The use of colorimeter (based on 478 observations) for quantifying β-carotene: combining the two relevant parameters in a selection index: (a – (h2*10) 50 y = 2.4242x - 1.7686 2 R = 0.6247 40 30 20 Selection index 10 0 2 6 10 14 18 -10 -20 All trans β-carotene

  11. Tolerance to PPD and/or training

  12. First evaluation of post-harvest physiological deterioration in Thailand (Huey Bong) 1. Training on the procedure 2. Introduction of potential sources of tolerance

  13. Gender issues

  14. Most women in Africa are involved in weeding cassava fields (typically for the first two months of the crop) Tolerance to herbicides could have a positive impact on the lives of these women. We are focusing on this trait Women in Africa and LAC are involved in peelingcassava for small processing facilities (i.e. gari,farinha, etc.) Thick peels facilitate peeling, but is undesirable for starch extraction The article “Genetic variability of root peel thickness and its influence in extractable starch from cassava (ManihotesculentaCrantz) roots” to be published in Plant Breeding adress this issue

  15. Better understanding of cassavareproductive biology

  16. New research on reproductive biology of cassava is required for the doubled haploids project Germination of pollen and definition of time required by the pollen tube to reach the micropyle of the ovule Stages of “normal” embryo sac development through the first four weeksafter pollination Definition of timing of stigma viability (before or after optimum timing) Pollination of female cassava flowers with castor pollen for the production of (doubled) haploid seeds

  17. Methodology to analyze the growth of pollen tube in un-pollinated female flowers (a-b); one hour after pollination (c-d) and three hours after pollination (e-f) P: pollen grain;PT: pollen tube

  18. Illustrations of the kind of preparations made to understand the development of the embryo sac in cassava

  19. Training Lisette Natalia Ramos(Ph.D. student, wide crosses)

  20. Plant Resources Colored root segregation pattern in an advance breeding family 17 μg 0 μg

  21. Plant Resources Advance breeding family CM8996for WFR MEcu72 MCol2246 MCol2246 Susceptible MEcu 72 Resistant

  22. Genetic and Genomics - MAS -Carotene Pathway in Plants IPP Geranylgeranyl diphosphate Phytoene synthase Phytoene Phytoene desaturase ξ-carotene desaturase Lycopene Lycopene-beta-cyclase  -carotene (vitamin A precursor)

  23. Genetic and Genomics - MAS

  24. Genetic and Genomics - MAS • Cassava SSRs were Silver stained • TheseSSRsareexpensive & time consuming to perform

  25. Genetic and Genomics - MAS • Electronic data capturing and analysis A B B 96 or 384 well-plates A B B A A B Previously developed genetic maps

  26. Processes and time-frame for developing breeder ready tools N N • SNPdiscoveryby genome RESCANing N N N N N N N N N N RRG Barcode Non-Illumina Adapter BREAD: Extending Unisexuality and Heterosisto Cosexual Cereal Crops Illumina Adapter Barcode Combine at least 48 genotypes per sequencing lane ~2-3X coverage