Modeling spatiotemporal dynamics and time to regional outbreaks of soybean rust in southern Brazil

Transcript

1. Modeling spatiotemporal dynamics and time to regional outbreaks of soybean rust in southern Brazil Kaique Alves | Adam Sparks | Emerson Del Ponte
2. Why Soybean rust? More models?
3. Fungicides are key, but.. AZOX + CYPR TEBU
4. Background … from my talk last year
5. Follow up: now using 15 years - SBR prevalence All years (2005 - 2019) 2 States (south) PR and RS Commercial soybean fields First (date) report in a county 2,027 records ~15,000 records PR RS
6. Epidemic time MaxPrev AUDPC r Time_10 10% Prev90 Prev120 Temporal progress description / analysis Time to outbreak (Survival analysis)
7. NND Nearest neighbour distances Epidemic area Monthly maps Spatial description and analysis Initial Final area
8. Results: reports over time Peak in January Peak in February PR State RS State
9. Early onset Late onset Results: reports space and time
10. Results: NND over time
11. Results: Epidemic area over time Weak correlation between Initial and final epidemic area
12. Results: Correlations initial and final area Week after Sep 15 Jan 15
13. Results: Correlations initial and final area Jan 1st
14. Results: Time to outbreak ~ 70 days
15. Results: Principal Components
16. Results: Principal Components
17. From my talk last year, using 4 seasons
18. Euclidean distances Clustering method "ward.D2" Is the evidence consistent with other years?
19. Survival analysis Cox modeling Is time to outbreak affected by ENSO?
20. From my talk last year, using 4 seasons
21. What about the next season?
22. Conclusions • Large scale spatiotemporal spread varies among seasons and states • Multiple inoculum sources affect initial epidemic area • Early- and mid- season weather plays a major role • ENSO conditions useful as early warning Tactical Strategical Pre-season Growing season Risk prediction Outlook Forecasting Warning What's next? Develop models for predicting and mapping disease risk at the regional level Thank you! @edelponte