Fusarium head blight (FHB) in Brazil: what have we learned in 15 years?

Fusarium head blight (FHB) in Brazil: what have we learned in 15 years?

Summary of almost 20 of research on Fusarium head blight of wheat that started during my PhD in 2000 year. I provide a historical perspective of the work organized by interests that developed over time during the establishment of my research program on the topic.

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Emerson M. Del Ponte

November 17, 2020
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  1. Fusarium head blight (FHB) in Brazil: what have we learned

    in 15 years? Emerson M. Del Ponte Prof. Plant Pathology/Epidemiology
  2. Major disease of wheat and barley

  3. FHB +rain cool +rain warm -rain hot +rain/dry hot Wheat

    Blast 90% wheat crops (5 million T) Re-emergent in Brazil
  4. Photo: Dr. Flávio Santana Embrapa Trigo

  5. But also for other crops..

  6. Trail (2009) Why does FHB matter? Trail (2009)

  7. My FHB research in 6 episodes A new old problem

    Knowing the enemy The chief species Food in danger Man weapons Statistical modelling Computer simulation Disease forecasting Field surveys Molecular Identification Population genetics Chemistry Immunology Pathogen biology and ecology Plant-pathogen interaction Fungicide efficacy Meta-analysis Economic analysis Failure ahead? Fungicide resistance Phenotypic and molecular 1 2 3 4 5 6
  8. Episode one A new old problem

  9. Season Yield losses (%) 1984 - 1994 5.4 2000 17.5

    2001 13.4 2002 11.6 2003 26.2 2004 12.0 2005 22.2 2007 39.8 2008 23.2 2009 32.2 2010 17.8 A problem is noticed E.M. Reis R.T. Casa
  10. Del Ponte et al. (2005) Daily infection risk Why here,

    why now? How to predict it?
  11. Cumulative risk Model testing

  12. Cumulative risk Model testing

  13. No-till Cumulative risk Growing season (year) Del Ponte et al.

    (2009) Climate variability effect? no till?
  14. 9 years 11 locations 37 trials Meta-analysis of damage coefficients

  15. = 4,419.5 kg ha-1 = -46.3 kg ha-1 = 2,883.6

    kg ha-1 = -46.3 kg ha-1 Damage coefficient = -1.05% pp -1 Damage coefficient = -1.60% pp -1 Estimation of damage coefficients Duffeck et al. (2020)
  16. Crop simulation (10 dates x 28 years) FHB index FHB

    risk Attainable yield Yield losses (FHB) Damage coefficient (Dc) -1.05 % 1980-1989 1990-1999 2000-2007 10.3% 10.2% 5.8% Simulations of historical yield losses Duffeck et al. (2020)
  17. FHB index Fungicide spray (1x or 2x) Probability of non-offsetting

    costs $ Actual yield (Treated) Actual yield (Nontreated) Yield diff. (kg ha-1) Are fungicides profitable? Duffeck et al. (2020)
  18. Are two sprays worth? Duffeck et al. (2020)

  19. Episode Two Knowing the enemy

  20. The rise of a species complex Phylogenetic species recognition based

    on genealogical concordance
  21. FGSC species and trichothecene profile

  22. (Scoz et al 2009; Astolfi et al. 2012; Del Ponte

    et al. 2015) > 850 FGSC strains (5 years) Diverse population of species and toxin types
  23. (Del Ponte et al. 2015) Region shaping species distribution?

  24. South of Paraná: new surveys > 750 isolates Pereira et

    al. (2020)
  25. Crop and year effect on FGSC composition? Pereira et al.

    (2020)
  26. episode Three Food in danger

  27. n = 66 samples 2ppm line Del Ponte et al.

    (2012) Trichothecenes in wheat: NIV too!
  28. Duffeck et al. (2017) DON by state

  29. Duffeck et al. (2017) Zearalenone by state

  30. Duffeck et al. (2017) UHPLC vs. Elisa kit

  31. episode Four The chief species

  32. Spolti et al. (2012) Duffeck et al (unpublished) Is F.

    graminearum more aggressive?
  33. Is F. graminearum more aggressive? F. graminearum F. meridionale

  34. Machado et al. (unpublished) Is F. graminearum more aggressive?

  35. Species x Cultivar = P > 0.05 highly aggressive isolate

    Mendes et al. (2018) Cultivar x species effect?
  36. Nicolli et al. (2015) Chemical analysis Toxigenic potential

  37. Sexual fertility 1 Nicolli et al. (2015)

  38. 38 * * Sexual fertility 2 Machado et al. (Unpublished)

  39. Episode four Man weapons

  40. Machado et al. (2017) Fungicides do work, but varies with

    AI
  41. Machado et al. (2017) Do they protect yield?

  42. + 102 kg/ha Efficacy (%) Yield gain (kg/ha) Machado et

    al. (2017) Estimates of mean efficacy and yield gain
  43. Does a second spray pay off?

  44. QoI + DMI mixtures: are they worth? Barro et al.

    (2020)
  45. Yield gain from using mixtures? Barro et al. (2020)

  46. Effect size Yield Return (%) Fungicidea kb D SE(D) CI

    L c CI U c P value Y CI L c CI U c PYRA + METC 70 532.08 46.40 441.14 623.02 <0.0001 17.17 14.30 20.11 TFLX + PROT 45 494.99 45.09 406.60 583.38 <0.0001 16.21 13.14 19.37 TEBU 25 448.20 54.04 342.27 554.13 <0.0001 14.68 11.24 18.22 AZOX + TEBU 25 462.43 48.92 366.53 558.32 <0.0001 14.74 11.54 18.02 TFLX + TEBU 40 468.24 42.43 385.08 551.41 <0.0001 14.66 11.92 17.46 PYRA + METC 1X 23 413.72 53.66 308.53 518.90 <0.0001 12.97 9.70 16.35 Estimates of mean efficacy and yield gain Barro et al. (2020)
  47. Show me the money again Barro et al. (2020)

  48. episode six Failure ahead?

  49. EC50 levels for 50 strains from RS Spolti et al.

    (2012) Sensitivity to Triazoles (TEBU and METC)
  50. EC50 levels for 35 strains R2 R1 R2 Machado et

    al. (unpublished) Sensitivity to TEBU and Carbendazim
  51. F. graminearum less sensitive to TEBU Machado et al. (unpublished)

    R2 R1 R2 F. graminearum others F. graminearum others 15-ADON 15-ADON 15-ADON Are EC50 dependent on FGSC species?
  52. Check Check Check Fungicide Fungicide Fungicide Less sensitive isolates Sensitive

    isolate Does it affect control efficacy?
  53. 1. Previous crop not important risk factor in the subtropics

    (no-till) 2. At least two important species/chemotypes to concern 3. DON and NIV should be a target in surveys (only DON now) 4. One seems more adapted to wheat environments (F. graminearum) 5. Breeders should use the most aggressive strains Lessons learned
  54. 6. One spray of tebuconazole is a cost-effective choice (yield)

    7. Premixes (DMI+QoI) likely do not break even on costs 8. The pathogen may be adapting to fungicides - future concern? Lessons learned
  55. Open FGSC database

  56. Cooperative trial network

  57. Key Collaborators Dr. J. Maurício Fernandes Dr. Gary Bergstrom Dr.

    Willingthon Pavan Dr. Dauri Tessmann Dr. Todd Ward Dr. Eliana Furlong Dr. Casiane Tibola Dr. Flávio Santana Dr. Lisa Vaillancourt Graduate Students (2008 - now) Paula Astolfi Piérri Spolti Paulo R. Kuhnem Jr. Camila Nicolli Gabriela Mendes Franklin Machado Maíra Duffeck Jhonatan Barro Acknowledgements
  58. Thank you! @edelponte