Download - Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14
![Page 1: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/1.jpg)
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
![Page 2: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/2.jpg)
Abou
nd
Topsin-M
Gray mold management in strawberry
![Page 3: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/3.jpg)
Widespread Resistance in FL Strawberry Fields13.5
86.5Pristine
Sensitive Resistant
14.6
85.4
Cabrio
47.352.7
Switch (Cyprodinil)
60
40
Elevate
5
95Topsin-M
100
Switch (fludioxonil)
![Page 4: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/4.jpg)
Botrytis outbreak on strawberry in 2012
![Page 5: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/5.jpg)
The many faces of Botrytis on blueberry
Leaf
Shoot blight Total blossom damage
Sporulation on a blossom
Shoot tip
Green and mature fruit
![Page 6: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/6.jpg)
Gray mold management in blueberry
Trade name Active ingredient Efficacy* Resistance Risk
Cabrio Pyraclostrobin + (curative ?) ++++
Pristine Pyraclostrobin + Boscalid ++ ++++
Fontelis** Penthiopyrad +++ +++
Elevate/Captevate Fenhexamid +++ +++
Switch Fludioxonil+cyprodinil ++++ +/+++
Captan/Captec Captan ++ (Protectant)
?
* Efficacy will depend on frequency and distribution of resistant population** Labeled for lowbush blueberry
![Page 7: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/7.jpg)
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
![Page 8: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/8.jpg)
Fungicide sensitivity in Botrytis in Central- FL
* The other active ingredient of Pristine
Switch
![Page 9: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/9.jpg)
Is population shift between crops a potential source of resistance in blueberry?
?
Labeled in strawberrynot in blueberry
From the same chemical group
New, potentially effective
* Labeled for lowbush blueberry** Not registered yet
![Page 10: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/10.jpg)
Some variability but resistance is spread across locations
a Number of isolates from each field* Both active ingredients of Switch
Location County n a Cabrio Pristine Elevate Cyprodinil* Fludioxonil*1 Polk 15 100.0 73.3 40.0 40.0 0.02 Polk 10 90.0 10.0 40.0 40.0 0.03 Citrus 15 100.0 80.0 20.0 60.0 0.04 Citrus 20 85.0 30.0 45.0 30.0 0.05 Citrus 40 85.0 52.5 52.5 42.5 0.06 Hillsborough 20 100.0 65.0 85.0 60.0 0.07 Hillsborough 10 90.0 60.0 10.0 20.0 0.08 Hillsborough 15 86.7 33.3 20.0 60.0 13.39 Hillsborough 19 64.4 42.1 21.1 31.6 0.0
10 Hillsborough 28 100.0 78.6 71.4 60.7 0.0
Resistance frequency (%)
![Page 11: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/11.jpg)
Management at risk because of multiple resistance
MFR2 2 fungicidesMFR3 3 “MFR4 4 “MFR5 5 “MFR6 6 “MFR7 7 “
Phenotype Resistant to
MFR = The same isolate may be resistant to 2, 3, 4 or more fungicides, simultaneously.
![Page 12: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/12.jpg)
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)
![Page 13: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/13.jpg)
Is reducing number of sprays the solution?
Citrus County: Floral City
Polk County: Lake Alfred
Hillsborough County:DoverPlant CityBalm
Locations of weather stations
![Page 14: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/14.jpg)
Reducing sprays doesn’t seem to affect control efficacy
Calendar = Weekly applicationAlert = Spray only when conditions are conducive to Botrytis
2011-2012 Strawberry season
17* 9
* Number of fungicide applications/season
168
21
11
15 10
![Page 15: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/15.jpg)
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
http://www.agroclimate.org/tools/strawberry/
Monitoring weather conditions, sign up, alerts:
![Page 16: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/16.jpg)
Additional management recommendations
https://edis.ifas.ufl.edu/hs380
![Page 17: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/17.jpg)
Perspective
Conduct additional resistance monitorings across the State: Please contact us
Develop efficient rotation programs
Investigate the impact of different sources of botrytis inoculum
![Page 18: Achour Amiri, Philip F. Harmon, Natalia A. Peres Winter BGA meeting, Plant City, FL, 02/20/14](https://reader035.vdocuments.us/reader035/viewer/2022081520/56816924550346895de05b05/html5/thumbnails/18.jpg)
Acknowledgements
Participating growers Mr. Gary K. England Strawberry pathology lab team
Contact Information:
Dr. Achour AmiriGulf Coast Research and Education Center14625 CR 672Wimauma, FL, 33598
Phone: 813-633-4153Email: [email protected]
Dr. Harmon and Dr. Peres