1 / 18

Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14

Early signs of widespread fungicide resistance in Botrytis across blueberry fields in central Florida. Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14. Gray mold management in strawberry. Abound . Topsin -M .

justis
Download Presentation

Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Early signs of widespread fungicide resistance in Botrytis across blueberry fields in central Florida Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14

  2. Gray mold management in strawberry Abound Topsin-M

  3. Widespread Resistance in FL Strawberry Fields

  4. Botrytis outbreak on strawberry in 2012

  5. The many faces of Botrytis on blueberry Total blossom damage Shoot tip Shoot blight Green and mature fruit Sporulation on a blossom Leaf

  6. Gray mold management in blueberry * Efficacy will depend on frequency and distribution of resistant population ** Labeled for lowbush blueberry

  7. Survey of fungicide sensitivity in Botrytis in Central- FL • 10 locations surveyed in 2013 (March-May) • 2 in Polk County • 3 in Citrus County • 5 in Hillsborough County • Total number of isolates: 192 • Sensitivity to 9 fungicides from different chemical groups

  8. Fungicide sensitivity in Botrytis in Central- FL Switch * The other active ingredient of Pristine

  9. Is population shift between crops a potential source of resistance in blueberry? ? New, potentially effective Labeled in strawberry not in blueberry From the same chemical group * Labeled for lowbush blueberry ** Not registered yet

  10. Some variability but resistance is spread across locations a Number of isolates from each field * Both active ingredients of Switch

  11. Management at risk because of multiple resistance PhenotypeResistant to MFR2 2 fungicides MFR3 3 “ MFR4 4 “ MFR5 5 “ MFR6 6 “ MFR7 7 “ MFR = The same isolate may be resistant to 2, 3, 4 or more fungicides, simultaneously.

  12. Best management practices • Spray when the plant is most susceptible: Flowering • and • When weather conditions are conducive: Temperature (~68°F) and wetness (10 to 14h)

  13. Is reducing number of sprays the solution? Locations of weather stations Citrus County: Floral City Polk County: Lake Alfred Hillsborough County: Dover Plant City Balm

  14. Reducing sprays doesn’t seem to affect control efficacy 2011-2012 Strawberry season 11 21 8 16 10 15 9 17* * Number of fungicide applications/season Calendar = Weekly application Alert = Spray only when conditions are conducive to Botrytis

  15. Spray at appropriate timing and growth stage • Low Botrytis Risk: spray Captan • Moderate Botrytis risk: spray Elevate, Pristine, Fontelis (lowbush) • High Botrytis risk: spray Switch Preferably within the 24 hours following the alert Monitoring weather conditions, sign up, alerts: http://www.agroclimate.org/tools/strawberry/

  16. Additional management recommendations https://edis.ifas.ufl.edu/hs380

  17. Perspective • Conduct additional resistance monitoringsacross the State: Please contact us • Develop efficient rotation programs • Investigate the impact of different sources of botrytis inoculum

  18. Acknowledgements Contact Information: Dr. Achour Amiri Gulf Coast Research and Education Center 14625 CR 672 Wimauma, FL, 33598 Phone: 813-633-4153 Email: aamiri@ufl.edu Dr. Harmon and Dr. Peres • Participating growers • Mr. Gary K. England • Strawberry pathology lab team

More Related