Page 1
Fusarium Dieback in California: another ambrosia beetle associated disease of avocado and urban forest
A.Eskalen1, S.C.Lynch1,F.Na,J.S.Mayorquin1,J.D.Carrillo1,A.Lira2,T.Atkinson3
1DepartmentofPlantPathologyandMicrobiology,UniversityofCalifornia,Riverside,CA925212Ecologyandevolutionarybiology,Inecol,Mexico
3EcologyofambrosiabeetlesfromUniversityofTexas
AvocadoLaurelWiltSummit,Homestead,FloridaNov3-4,2016
Page 2
Outline• Overview• CurrentreproductivehostsofSHB• CurrentsituationonavocadoinCalifornia• CurrentsituationonurbanforestinCalifornia• Controlstrategiesandbestmanagementpracticesonavocado
Page 3
LosAngelesCoOrangeCo
SanBernardinoCoRiversideCoVenturaCo.
PolyphagousShotHoleBorerPSHB
Euwallacea sp.
KuroshioShotHoleBorerKSHB
Euwallacea sp.SanDiegoCoOrangeCo
SantaBarbaraCoSanLuisObispoCo
Graphiumeuwallaceae
Paracremoniumpembeum
Fusariumeuwallaceae(Freemanetal.2013) (Lynchetal.2015 (Lynchetal.2015)
Fusarium sp. Graphium sp.(Newspecies) (Newspecies)
A.Eskalen
Polyphagous and Kuroshio Shot Hole Borersand their symbiotic fungi
Page 4
Koch’s Postulates – Pathogenicity test
MeanlesionlengthsonavocadoandboxeldershootsinoculatedwithisolatesofFusarium euwallaceae, Graphiumeuwallaceae andParacremonium pembeum.VerticallinesrepresentstandarderrorofthemeanaccordingtoFisherprotectedLeastsignificantdifference(LSD)meanseparationtestatα=0.05.
BB
A
0
2
4
6
8
10
12
14
16
Fusarium euwallaceae Graphium euwallaceae Acremonium sp. Control
Lesi
on L
engt
h (c
m)
Persea americana Acer negundo
C
Paracremonium pembeumGraphium euwallaceae
Avocado BoxElder
• Lynch and Eskalen , 2016. Mycologia, 108(2), pp.313-329
Page 5
Growth rate of symbiotic fungi in different temperature
Fungaldiameter(cm)
Temperature°C
12345678910
5 10 15 20 25 30 35 40
Paracremonium pembeum
Graphium euwallaceae
0
Fusarium euwallaceae
Page 6
Fusarium dieback and symbiotic fungal pathogens
Page 7
+51&80:;%'718<:1&4:=5'':>%$#
N7F)(B)8 Q=5$' *$0B*2+S$*A(;%2#J'&#QPB$'5B: '+6B'S#
!"$%&'()* !"$%&'()*
Page 8
Number of reproductive hosts that beetle/fungus can produce their offsprings
1. Boxelder(Acernegundo)*2. Californiasycamore(Platanusracemosa)*3. Londonplane(Platanus xacerfolia)4. Redwillow(Salixlaevigata)*5. Blackwillow(Salixgooddingii)*6. Arroyowillow(Salixlasiolepis)*7. Cottonwood (Populus fremontii)*8. Blackpoplar(Populus nigra)*9. Blackcottonwood(Populus trichocarpa)*10. Mimosa (Albizia julibrissin)11. EnglishOak(Quercusrobur)12. Engelmannoak(Quercusengelmannii)*13. Valleyoak(Quercuslobata)*14. Paloverde(Parkinsoniaaculeata)*15. Bigleafmaple (Acermacrophyllum)*16. Japanesemaple (Acer palmatum)17. Castorbean (Ricinus communis)18. CanyonLiveoak(Quercus chrysolepis)*19.Avocado (Persea americana20.Tridentmaple(Acerbuergerianum)21.Coastliveoak (Quercus agrifolia)22.WhiteAlder (Alnus rhombifolia)*23.Titoki (Alectryon excelsus)24.CorkOak(Quercus suber)
Eskalen andLynch,2016.Unpublisheddata
25.Coraltree (Erythrina corallodendon)26. Bluepalo verde (Cercidium floridum)*27.MoretonBayChestnut (Castanospermum australe)28.Brea(Cercidium sonorae)29.Mesquite(Prosopis articulata)*30.Weepingwillow (Salixbabylonica)31.Chineseholly (Ilex cornuta)32.Camelia (Camelliasemiserrata)33.Acacia(Acacia spp.)34.Liquidambar(Liquidambarstyraciflua)35.RedFloweringGum (Eucalyptusficifolia)36.Japanesewisteria(Wisteriafloribunda)37.Goodding's blackwillow(Salixgooddingii)*38.Treeofheaven(Ailanthusaltissima)39.Kurrajong (Brachychiton populneus)40.Blackmissionfig(Ficus carica)41.Japanesebeech(Faguscrenata)42.Denselogwood(Xylosma congestum)43.MuleFat(Baccharis salicifolia)*44.Carrotwood (Cupaniopsis anacardioides)45.Californiabuckeye(Aesculus californica)*46.MuleFat(Baccharis salicifolia)*47.KentiaPalm(Howea forsteriana)48.KingPalm(Ptychosperma elegans)
Page 9
ParksBackyardTrees
Urban Forests Impacted
GolfCourses
StreetTrees
Page 10
MixedEvergreenForests OakWoodlands FoothillWoodlands
Riparian
California Native Plant Communities Impacted
Page 11
Current Situation onavocado in California
Page 12
• Totalgrovessurveyed:26• 1ha(2.47acres)monitoringplotestablished• Examinedeverytreewithintheplot• Totaltreessurveyed:4,346x3times
Monitoring infested avocado groves
Page 13
SHB infestation habit on avocado in California
Page 14
Branch dieback on Avocado
Page 15
Sugar exudate and internal symptoms on avocado branch
Page 16
Beetle attack on branch collar and pruning wounds on avocado
Page 17
Current Situation in Urban Forest in California
Page 18
Damage on Landscape trees
Page 19
Mean(attacks/m^2) vs. TimePark
Carbon Canyon
atta
cks/m
^2
0
50
100
150
200
250
Aug '15Sep Oct Nov
Dec Jan Feb Mar AprMay Jun Jul
Aug '16
Time
Beetle attack incidence on an infested sycamore tree overtime
Page 20
May2015 Feb2016
Tijuana River Valley Before and After Pictures
Boland,2016
Page 21
Control Strategies
Page 22
Laboratory Fungicide Screening Experiment
aaaab
abb
cc
dNoInhibitionNoInhibitionNoInhibitionNoInhibition
0 1 2 3 4 5
Metconazole
Pyraclostrobin
Tebuconazole
Thiabendazole
Propiconazole
Triflumizole
Fluopyram
Mycobutanil
Pyrimethanil
Fluxapyroxad
Trifloxystrobin
Triadimefon
Azoxystrobin
EC50Values(ug/ml)
Treatm
ent
EC50Values
Page 23
TreeIVinjectionsystem Quick-JetAirinjectionsystem
Field Pesticide Trial on Avocado
Page 24
This slide is blank on purpose. Please see next slide.
Page 25
• Iftheinfestationisonthebranchcollar,cutintobranchcollar.
Best Management Practices on Avocado
• SpraypruningwoundwitheitherBifenthrin or2%(Bacillussubtilis).
Page 26
• Chipinfestedwoodon-sitetoasizeofoneinchorsmaller.• Solarizechippingmaterialusingclearplastictarpforseveralmonths
• CompostchippingmaterialandthenuseasmulchinthegroveIfthebranchistoolargetochip
• Fumigationwithphosphinegas(Arpaia andRios,2015)
• Don'tmoveinfestedplantmaterialwithoutchippingandsolarizing
Best Management Practices on Avocado Cont.
Page 27
FrederiqueRevenchon,Inecol,MexicoBenFaber,FarmAdvisor,VenturaCounty,CA\RichardDemerjian,UCIrvineSoniaRios,UCCEFarmAdvisor,SanDiegoSabrinaDrill,UCCELAandVenturaDanBerry,HuntingtonBotanicalGarden,GaryBender,UCCE,Emeritus,SanDiegoCo.JanisGonzales,UCCESanDiegoJimFolsom,HuntingtonBotanicalGardenJiriHulcr,Univ.ofFloridaKerryO’Donnell,NCUR-ARS-USDAMaryLuArpaia,UCRiversideKimCorella,CalFireTomSmith,CalFireJoeBarcinas,PCATomRoberts,PCAMathewHand,PCALindaBellamy,VentureSusanFrankel,USDAForestServiceTomAtkinson,UniversityofTexasSeanFeirer,UCANRJimDowner,UCCEVentura
CaliforniaAvocadoCommissionU.S.ForestService,OCParks,UCIrvine,UCANR,USDAFarmBill,Arborjet,Mauget,USDAForestService,Cal-Fire,HuntingtonbotanicalgardenandLAarboretum,UCMexus,Inecol,Mexico.
Collaborators
www.eskalenlab.ucr.edu