Botrytis Management in Cut Roses · 10.0 12.5 15.0 17.5 20.0 22.5 50 60 70 80 90 0 10 20 30 40 50 60 ... After 4 h of incubation (spores present on wet petals), roses display no symptoms.

BotrytisManagementinCutRoses

MelissaMuñoz,JamesE.Faust&GuidoSchnabel

Ph.D. Horticulture• FloriculturePhysiology• Effectsofenvironmentalandculturalfactorson

theproductionofornamentalgreenhousecrops

• Botrytis foundonpansyflowersataFloridanurserythatwasresistanttoallofthemainfungicidesusedtocontrol Botrytis

Ph.D. Plant pathology• Integratedmanagementofdiseases• Botrytis controlinstrawberriesandblackberries• Fungicideresistancemechanisms• Decision-supportmodelsandsmart-phoneapps

toreduceandbettertimepesticideapplications

Context

BBCnews

• Botrytiscinerea:üUbiquitous

ü200speciesplanthostsüNecrotrophic

• Roses:üReductioninthepostharvestquality,leadingtosubstantialeconomicloss

bygrowersandwholesalers

The problem

The problem

400x 400x

Ø LeafwetnessØ 93%Relativehumidity

Ø 15-25ºC Optimum.0ºC to35.5ºC

DiseasetriangleSusceptiblehost

VirulentpathogenConduciveenvironment

ToevaluateweatherconditionsincommercialgreenhousesandtheirrelationshipwithBotrytis occurrence

Context

• SAS- StrawberryAdvisorySystem: isawebsite,andsmarth-phoneappthatprovidesaneasywayforstrawberrygrowersinFloridatotrackandforecastrisklevelsforBotrytisandanthracnosefruitrot

diseases.Italsoprovidesfungicideapplicationrecommendationsandallowsgrowerstoreceivealertsforselectedweatherstationsviapush

notifications.

Installationofweatherstations

• Solarradiation(W/m2)• Leafwetness(min)• Airtemperature(°C)• Relativehumidity(%)• Dewpoint(°C)• Leaftemperature(°C)• Soiltemperature(°C)• Electricalconductivity(mS/cm)• Watercontentofsoilmedia(%)• Windspeed(m/s)• Winddirection

Typicaldailyweatherpattern

Sola

r rad

iatio

n

(W/m

2)Ai

r tem

pera

ture

(ºC

)Re

lativ

e hu

mid

ity

(%)

Leaf

wet

ness

(min

/hou

r)

0100200300400500

10.012.515.017.520.022.5

5060708090

0102030405060

6:00

7:00

8:00

9:0010

:0011

:0012

:0013

:0014

:0015

:0016

:0017

:0018

:0019

:0020

:0021

:0022

:0023

:00 0:00

1:00

2:00

3:00

4:00

5:00

Hour

Solarradiation(W/m2)

Airtemperature(oC)

Relativehumidity(%)

Leafwetness(min/h)

BOTRYTIS RISKMODELDEVELOPMENT

Botrytisinfectionrisk

Month DateLeafwetness

(h)Temperature

(oC)Infectionrisk

(%)Risk

February 2/20/17 7.5 11.4 6.3 NoFebruary 2/21/17 0.0 16.9 1.4 NoMarch 3/17/17 12.5 11.6 16.9 NoApril 4/15/17 12.5 11.3 15.9 NoApril 4/17/17 24.0 14.3 88.1 HighMay 5/29/17 11.5 11.6 14.2 NoMay 5/30/17 10.6 11.9 12.5 NoJun 6/9/17 19 14.3 67.7 MidJun 6/14/17 15.3 13.2 36.9 LowJun 6/15/17 8.0 12.8 8.5 NoJun 6/16/17 24.0 15.4 91.5 HighJun 6/29/17 13.5 11.1 17.9 noJun 6/30/17 17.8 13.2 51.8 MidJuly 7/1/17 20.1 15.0 76.6 HighJuly 7/15/17 14.5 11.7 24.5 NoJuly 7/28/17 15.25 11.9 29 No

August 8/17/17 14.5 11.7 24.9 NoSeptember 9/02/17 14.8 11.7 25.6 NoSeptember 9/03/17 24 12.2 76 High

Predictedvs.realBotrytisincidencevalues

0102030405060708090100

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35

Incide

nce(%

)

Week

ActualBotrytisIncidence PredictedBotrytisIncidence

• Thediseaseriskmodelhasvalueandcanbecomeaspartofanintegratemanagement

programofBotrytis• Weatherstationsareatoolthatmayimprovetimingforfungicideapplications

ToevaluateBotrytissporesdensityincommercialgreenhousesandtheirrelationtoculturalpractices

Installationofsporetraps

Countingsporesprocess

100x400x

Spores density

Spores density

Spores density

Culturalpractices

• Harvesting• Pinching• Sweepingfloors*• Blowing(debris

removal)*• Manualdebris

removal• Downymildew

removal

• Botrytisremoval• Deadstemspruning• Deadstemsremoval• Weeding• Drenching• Fungicidespray

application• Pesticidespray

application

• Thermo-fogging• Supplementary

wateringofbeds• PGRsapplication• Cuttingzonecleaning• Plasticchange• Fertilizercontainers

change

ThenumberandtypeofculturalpracticeshaveaneffectonBotrytissporedensity

TodetermineBotrytis severityindifferentrosetissuesfromcommercialshipments

• SouthAmericanStudy:• OneFarm• 2Greenhouses• OneSusceptibleVariety:OrangeCrush• SixShipments

• GeographicalStudy:• FourLocations:Ecuador,Africa,Colombia;

GuatemalaorMexico• FourShipments

AssessingBotrytisOccurrence&SeverityonCommercialRoseShipments

Inner Petals

Outer Petals

Mid Petals

Sepals

Ovary andStamens

Leaves

Stems

SampleCollectionandProcessing

Petals

Results:Botrytis occurrenceindifferentplanttissue:

SouthAmericaStudy

Petalsarethemostsusceptibletissue

Stems

Sepals

Stamens&ovary

73.7%

13.2%

7.9%

5.3%

Results:Botrytis occurrenceindifferentplanttissue:

SouthAmericaStudyStems

Sepals

Stamens&ovary

Outer34.2%

13.2%

7.9%

5.3%

Petals

Asignificantportionoftheinfectionoccursintissuesthatarenotexposed(Midandinnerpetals,stamensandovary)

Mid26.3%

Inner13.2%

ToassessfungicideresistanceprofilesinBotrytis isolatesfromcommercialcutroses

Context

• Resistencia:referstoanacquired,heritablereductioninsensitivityofafungustoaspecificanti-fungalagent(orfungicide).• FRAC (Fungicideresistanceactioncommittee):Grouptogetherthefungicidesthatareinriskofcrossresistancedevelopment,becausehaveasimilarmodeofaction

Inner Petals

Outer Petals

Mid Petals

Sepals

Ovary andStamens

Leaves

Stems

ControlFRAC9: Cyprodinil

FRAC12:FludioxonilFRAC17: Fenhexamid

FRAC2:IprodioneFRAC1:Thiophanate-methyl

FRAC19:Polyoxin DFRAC7:Boscalid

FRAC7:FluopyramFRAC7:Penthiopyrad

FRAC7:IsofetamidFRAC7:Pidiflumetophen

FUNGICIDERESISTANCEPROFILES:11FUNGICIDESTHATBELONGTO7CHEMICALCLASSES(FRAC)

FungicideResistanceProfiles

SouthAmericaStudy49Singlesporeisolates

GeographicalStudy58Singlesporeisolates

FungicideResistantIsolates:6Shipments(SouthAmericaStudy)

020406080100

FRAC

1FRAC

2FRAC

9FRAC

7FRAC

17

FRAC

7FRAC

7FRAC

7FRAC

12

FRAC

7FRAC

19

ResistantIsolates(%

)

Shipment2n=11

0.020.040.060.080.0100.0

FRAC

1FRAC

2FRAC

9FRAC

7FRAC

17

FRAC

7FRAC

7FRAC

7FRAC

12

FRAC

7FRAC

19

ResistantIsolates(%

)

Shipment3n=5

0.020.040.060.080.0100.0

FRAC

1FRAC

2FRAC

9FRAC

7FRAC

17

FRAC

7FRAC

7FRAC

7FRAC

12

FRAC

7FRAC

19

ResistantIsolates(%

)

Shipment5n=7

0.020.040.060.080.0100.0

FRAC

1FRAC

2FRAC

9FRAC

7FRAC

17

FRAC

7FRAC

7FRAC

7FRAC

12

FRAC

7FRAC

19

ResistantIsolates(%

)

Shipment6n=9

ResistantIsolate SensitiveIsolate

020406080100

FRAC

1FRAC

2FRAC

9FRAC

7FRAC

17

FRAC

7FRAC

7FRAC

7FRAC

12

FRAC

7FRAC

19

ResistantIsolates(%

)

Shipment1n=4

020406080100

FRAC

1FRAC

2FRAC

9FRAC

7FRAC

17

FRAC

7FRAC

7FRAC

7FRAC

12

FRAC

7FRAC

19

ResistantIsoates(%)

Shipment4n=13

ResistantIsolate SensitiveIsolate

FungicideResistantIsolates(SouthAmericaStudy)

0102030405060708090100

ResistantIsolates(%

) FungicidesappliedinthelastyearFluxapyroxad :FRAC7Pyrimethanil:FRAC9Famoxadone:FRAC11Azoxystrobin:FRAC11Propamocarb:FRAC28Fluopicolide:FRAC43Cymoxanil:FRAC27Tebuconazole:FRAC3Fluazinam:FRAC29Prochloraz:MultisiteCaptan:Multisite

Iminoctadine:MultisiteZincdiethyldithiocarbamate:Protectant

FungicideResistantIsolates(GeographicalStudy)

Aislamientos resistentes Aislamientos sensibles

0102030405060708090100

FRAC1

FRAC9

FRAC2

FRAC17

FRAC7

FRAC7

FRAC7:

FRAC12

FRAC7

FRAC7

FRAC19

Resistantisolates(%

)

Ecuadorn=23

0102030405060708090100

FRAC1

FRAC9

FRAC2

FRAC17

FRAC7

FRAC7

FRAC7:

FRAC12

FRAC7

FRAC7

FRAC19

Resistantisolates(%

)

Guatemalan=4

0102030405060708090100

FRAC1

FRAC9

FRAC2

FRAC17

FRAC7

FRAC7

FRAC7:

FRAC12

FRAC7

FRAC7

FRAC19

Resistantisolates(%

)

African=26

0102030405060708090100

FRAC1

FRAC9

FRAC2

FRAC17

FRAC7

FRAC7

FRAC7:

FRAC12

FRAC7

FRAC7

FRAC19

Resistantisolates(%

)

Colombian=4

0102030405060708090100

FRAC1 FRAC9 FRAC2 FRAC17 FRAC7 FRAC7 FRAC7: FRAC12 FRAC7 FRAC7 FRAC19Re

sistantisolates(%

)

Mexicon=2

Resistance:

• Insomechemicalclasses,theresistanceeffectisconservedevenwhenthefungicidesarenotusedinthepresentbuttheywereusedbeforee.g.FRAC1•Resistancetosomefungicidescanbedecreasedordisappeariftheresistancehasaneffectonthefitnessofthepathogenandnoapplicationsofthefungicidearedoneinawhilee.g.FRAC7- Boscalid onstrawberries

Botrytissymptoms

Abioticsymptoms

Pinkspotson petals arenot Botrytis symptoms

Alternaria sp.

Aspergillussp.

Diplodia sp.

400x

400x

400x

BioticSymptoms

12h

8hSporesuspension Water

ASSESSTHEINITIALSYMPTOMSFORBOTRYTIS

4h

Incubate(highRH)

DAY1 DAY2 DAY3 DAY4 DAY5 DAY6 DAY7

4h

8h

12h

Incubatio

ndu

ratio

nSymptomDevelopment Incubate

(highRH)

DAY9

LatentInfections

After4hofincubation(sporespresentonwetpetals),rosesdisplaynosymptoms.However,latentinfectionhasoccurredandsporulationwilloccuriftheflowersareexposedtotheproperconditions(highhumidity).

After>8hofincubation,Botrytissymptomsappearonpetals(beige/tan/discoloredspots).

ComprehensiveapproachSusceptiblehost

VirulentpathogenConduciveenvironment

CaandSicontentinrosetissue

00.20.40.60.81

1.21.41.61.82

Ca(%

)

Rosetissue

Calciumcontentindifferentrosetissue

00.050.1

0.150.2

0.250.3

0.350.4

Si(%

)Rosetissue

Sicontentindifferentrosetissue

Acknowledgements

SchnabelLab:Mengjun Hu

MadelineDowlingMarthaFroelichKarenBrysonLinusSmithBrodieCox

FaustLab:KatieBennettKellyLewisJiwoo Park

QUESTIONS?Questions?

¡Muchas gracias!