control of xylella fastidiosa in organicolive oilproduction€¦ · vincenzo verrastro...
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VINCENZO VERRASTRO
Mediterranean Agronomic Institute of Bari, CIHEAM BARI (Italian site)
This project has received funding from the European Union’s Horizon
2020 research and innovation programme under grant agreement
No 727987
Control of Xylella fastidiosa in organic olive oil production
IDENTIKIT OF AN “UNUSUAL” PATHOGEN• Xylem-limited bacterium
• Symptoms are not sufficient todefine a diagnosis
• Active principles MUST reachxylem and MUST be systemic
• Root absorption (????)
Vessels occlusion: agglomerates of cells and biofilm• Genetically, morphologically and
biologically different from otherphytopathogenic bacteria
Woody vases
Woody vases
MembraneWater stress symptoms – NOT SPECIFIC
Courtesy: EFSA 2018
IDENTIKIT OF AN “UNUSUAL” PATHOGEN• High variability both genetic and biological
Different ability in infecting plants, with a widerange od aggressiveness. Toady there is a widegenetic of the bacteria: biology remains a critical andimportant point
There is a general correlation between subspecies and crop that can be damaged
fastidiosa
multiplex
pauca
6 subspecies
1 0Climatic suitability
5
Europe and Xylella
Courtesy Dr. J. Navas
2013
2015
20162017
2018
2018
• 4 EU countries are facing outbreaks or epidemics
• 3 strains belonging to 3 subspecies and some «new» strains
• more than 80 species susceptible (host plants)
• Olive and almonds the most damaged
High risk in Mediterranean areas:temperate with dry-hot summer
2018
2019From 2013 the «speed» of the XF has been of 30 km/year
INFECTED AREAINFECTED AREA
From Olive Quick Decline Syndrome (OQDS) to OQD
Gallipoli, October 2013
Progression of the disease symptoms on the infected trees
Gallipoli, March 2016
Giant of Alliste (1500 years)30 September 2014
30 September 2018
First symptoms (north sided on the upper part)
2016 near Gallipoli (South Salento )
2019 near Gallipoli (South Salento )
France outbreaks
Update: July 2018
PACA region-67 foci-23 plant species
Corsica region-354 outbreaks-36 plant species-80% focolai - P. myrtifolia
as determined by analyses of samples taken in the frame of the National survey plan and control of imported plants
-6 outbreaks between700m e 950m over the sea level
PositiveUndetermined
PositiveUndetermined
PositiveUndetermined
http://www.alpes-maritimes.gouv.fr/Politiques-publiques/Securite-et-protection-de-la-population/Xylella-Fastidiosa/Communiqueshttp://www.corse-du-sud.gouv.fr/xylella-fastidiosa-une-menace-qui-demande-une-a1409.html
2017 - containment
Eradication
Acacia dealbata Link Acer pseudoplatanus L. Anthyllis hermanniae L. Artemisia arborescens L. Asparagus acutifolius L.
Calicotome villosa (Poiret) Link 33%Cistus creticus L.
Cistus monspeliensis L. 10%Cistus salviifolius L. Coronilla valentina L. Cytisus scoparius (L.) Link Cytisus sp.Cytisus villosus LGenista x spachiana (syn. Cytisus racemosus Broom) Genista corsica (Loisel.) DC. Genista ephedroides DC. Genista x spachiana (syn. Cytisus racemosus Broom) Hebe sp.
Helichrysum italicum (Roth) G. Don 13% Lavandula angustifolia Mill. 10%Lavandula dentata L. Lavandula sp.Lavandula stoechas L. Lavandula x allardii (syn. Lavandula x heterophylla)Lavandula x intermedisMetrosideros excelsa Sol. ex Gaertn. Myrtus communis L. Nerium oleanderPelargonium graveolens L'HérPhagnalon saxatile (L.) Cass.
Polygala myrtifolia L. 26%Prunus cerasifera Ehrh. Prunus dulcis (Mill.) D.A Webb Quercus suber L. Rosa canina L.Rosmarinus officinalis L.
Spartium junceum L. 22%
Polygala myrtifolia
Lavendula sp.
Pelargoniumgraveolens
Cistus sp.
Myrtus communis
Hebe sp.
Cytisus racemosusRosmarinus officinalis
Genista hephredoides
Acer pseudoplatanus
Quercus suber
Prunus cerasifera
Asparagus acutifolius
Rosa x floribunda
Metrosideros excelsa
Spartium junceum
Calicotome villosa
Coronilla valentina
Helichrysum italicum
Artemisia arborecens
Phagnalon saxatilePrunus dulcis
Anthyllis hermaniae
Acacia dealbata
Host plants of Xf in France Positive samples in Corsica (%)
Calicotome villosa
Polygala myrtifolia
Spartium junceum
Helichrysum italicum
Cistus sp.
Lavendula sp.
Common to Mediterranean scrubs
Regional economic impact
+ in PACA Cercis silicastrum Euryops chrysanthemoidesMedicago sativa L.Westringia longifolia
Nerium oleander
Not a real epidemic situation but a “silent” infection. The question is what could happen in a near future of globalisation and taking into account the European genetic diversity
of XF?
Total positives = 740 (February 2019) & 21 host plants
228 (+)
Mallorca
Ibiza
Menorca139 (+)
Xf subsp. multiplex ST81
Xf subsp. pauca ST80
Olive 9%Wild olive 81%
Olive 41%Wild olive 46%
Xf subsp. multiplex ST81Xf subsp. multiplex ST7Xf subsp. fastidiosa ST1
Mallorca 476(+)Fig tree 4%
Olive 8%grapevine 14%Wild olive 26%
Almond 38%
Situation of Xylella fastidiosa in the Balearic islands
Situation of Xylella fastidiosa in the Balearic islands
Oleastermultiplex ST81/pauca ST80
PlumGrapesØ Host plants: 21 species of crops, ornamentals and natural vegetation
Almond
Walnut
fastidiosa ST1Cherry
fastidiosa ST1
Olivemultiplex ST81/pauca ST80
Figmultiplex ST81
fastidiosa ST1 /multiplex ST7,ST81 multiplex ST81
Subsp. fastidiosa ST1
Situation of Xylella fastidiosa in the Balearic islandsOlive (Olea europea var. europaea) Xylella fastidiosa subsp. multiplex
Situation of Xylella fastidiosa in the Balearic islandsOlive (Olea europea var. europaea) Xylella fastidiosa subsp. multiplex
Situation of Xylella fastidiosa in the Balearic islandsAlmond (Prunus dulcis) Xylella fastidiosa subsp. fastidiosa
Foto: Andreu Juan
Foto: Blanca B Landa
Foto: Andreu Juan
Foto: Blanca B Landa
Situation of Xylella fastidiosa in the Balearic islandsAlmond (Prunus dulcis) Xylella fastidiosa subsp. fastidiosa
Situation of Xylella fastidiosa in the Balearic islandsGrapes (Vitis vinifera) Xylella fastidiosa subsp. fastidiosa
Situation of Xylella fastidiosa in mainland Spain (Alicante)Almond (Prunus dulcis) Xylella fastidiosa subsp. multiplex ST 6
European Union projects on Xylella fastidiosa
Starting date: 01/11/2015Ending date: 31/10/2019
Xylella fastidiosa and itsvectors in olive, grapevine,citrus, stone fruit,ornamentals and landscapetrees of high socio-economicimportance.
Starting date: 01/11/2016Ending date : 31/10/2020
Research project to improve prevention,early detection and control of Xylellafastidiosa through the establishment of amultidisciplinary research program.
Starting date: 01/09/2017Ending date : 31/08/2021
Exchange scientific capacities amongEuropean and third countries, strengthenthe knowledge and the know-how on Xf inthird countries, raise awareness inrelation to Xf impacts and risks upon itsestablishment
XF Actors: Xylella Fastidiosa Active Containment Through a multidisciplinary-Oriented Research Strategy
The overall goal of the research program is todevelop scientific knowledge on thepathogenicity, transmissibility and hostsusceptibility to the Xf strains recovered inthe EU outbreaks, toward theimplementation of tools for pest riskassessment, for prevention and reduction ofthe impact of the Xylella-induced diseases.
The research actions are complementary tothose carried out under the Project POnTEthus ensuring effective cooperation andcontinuity with currently ongoing efforts.
XF Actors project: results achieved so farPUBLICATIONS
- 10 Books; 12 international papers and/or publications on referred journals in open access; 25 publications of featured bibliography on scientific papers ; 2 practice abstract on EIP –AGRI website coming from the XF Actors project
TECHNICAL RESULTS ACHIEVED
- Full genomes of XF obtained from several EU isolates,
- Full demonstration of pathogenicity of selected EU strains of XF, fulfilling the Koch postulate on olive an other crops
- Harmonized diagnostic test with interlaboratory validation able to define a common panel of recommended methods for detection of XF fromdifferent hosts
- Remote sensing approach techniques implemented at local level for early identification of Xylella-infected trees
- EU candidate vectors and confirmation of Philaenus spumarius as main responsible of XF transmission with two additional species in SouthernItaly (Apulia)
- Identification of traits of resistance to Xylella in olives
- Molecular research approaches for biocontrol strategies to restrain bacterial multiplication and virulence in the host plants.
- Innovative tools for risk assessment and prevention using different and complementary technologies
- Crosstalk (dialogue) with relevant stakeholders and local authorities to support knowledge transfer and exchange of views for implementationof integrated and organic control strategies
25
Xylellafastidiosapathways
IDENTIFICATION AND EVALUATION OF RISK REDUCTION OPTIONS TO REDUCE THE PROBABILITY OF ENTRYAND SPREAD
BACTERIA TRANSMISSION ON SHORT AND LONG DISTANCE
Infectious only through insect vectors
Crop or part of crops
Seeds
Detached wood
Fruits
Cut flowers
Courtesy EFSA
No seeds - No roots contact - No cutting tools
Obliged parasite
IDENTIKIT OF AN “UNUSUAL” PATHOGEN
Atypical "persistent" transmission:bacteria it’s alive only in the internalpart of the cuticle of the mouthpartVector lose infectivity at eachdevelopmental stage: adults maintainalive bacteria for all their lifetimeInspections are difficult and much more
controls or strategies !!!!!!!!!
Vectors are xylem-sap feeders NO SPECIFICITY
• 560 host species at world level• Only sometimes very critical damages• Crops reply in a different way linked to
immunity, resistance, susceptibility
XF HOSTS IDENTIFIED IN APULIA
1. Acacia saligna (Labill.)2. Amaranthus spp.3. Asparagus acutifolius L. 4. Catharanthus5. Chenopodium album L.6. Cistus creticus L. 7. Dimorphoteca fruticosa L.8. Dodonaea viscosa Jacq. 9. Eremophila maculata F. Muell. 10. Erigeron sumatrensis Retz. 11. Erigeron bonariensis L.12. Euphorbia terracina L.13. Euphorbia chamaesyce L.14. Grevillea juniperina L.15. Heliotropium europaeum L.16. Hebe spp.17. Laurus nobilis L. 18. Lavandula angustifolia Mill. 19. Lavandula stoechas L.
20. Myrtus communis L. 21. Myoporum insulare R. Br. 22. Nerium oleander L. 23. Olea europaea L. 24. Pelargonium x fragrans25. Phillyrea latifolia L. 26. Polygala myrtifolia L. 27. Prunus avium (L.) L. 28. Prunus dulcis (Mill.) D.A. 29. Rhamnus alaternus L. 30. Rosmarinus officinalis L. 31. Spartium junceum L. 32. Vinca 33. Westringia fruticosa (Willd.)34. Westringia glabra L.
Symptomless hosts
Crop species
• Olea europaea mostcommon host in Apulia
• Crop death for Oilves,Polygala and Thorntree
• But the level ofdamages depends onthe environmentalconditions
In Salento area we have different percentages of infection and damages
Olive trees : 100 % and death in a couple of years Almonds: 25% of crops and not death (after 5 years)
XF actors project defined the genetic characterization of Apulian strain
Costa Rica similitudesEvidences: - Unique ST (ST53) = Single introduction- Recent introduction (low SNPs)- Molecular dating of the introduction:
~2008 (1952-2015) (Vanhove et al., 2019)
Diffusion take place mainly from olive tree to olive tree
Xylella
Altre piante
Infected olive orchards: results of observations in Xf Project
July 2016 December 2017Susceptible variety (Ogliarola)
• Green points: no symptoms• Red points: big symptoms
Vectors catchmentstarting form the centreof one olive orchard =100-155 meters in 7-12 days
NOXylella
Other crops
Apulia situation for Olea Euroepa: a phytopatological apocalypse A combination of different factorswere the reason for the epidemic inSalento area
Vector population extremely high
Climatic conditions extremely favorable
Olive trees in Salento area are almost everywherewithout any interruption
OLIVE TREES IN SALENTO
Olea europea extremelysusceptible to Xylella fastidiosa
A bacterium strain very aggressive on olive trees and also on other 32 different species
Canopy very wide. In summer theideal place for the insect. Manypuncture = very high level ofbacteria «inside» the vector
Olive oil crop evergreen
In Salento only two varieties(Cultivar: Ogliarola and Cellina)
Crops in which no Xf bacteria was found
CITRUSDeath Olive Vineyards
Is there a cure for organic olives in Apulia region and in Mediterranean countries?
NOT AT THE MOMENT
Approaches on bacteria: multiplication happen only in xylem
AT WORLD LEVEL THERE IS NO CURE THAT MAY INFLUENCE BACTERIA DEVELOPMENTTHERE ARE NO ACTIVE PRINCIPLES THAT HAVE EFFICACY AGAINST XF
IS THERE A CURE? NO BUT THERE CAN BE A STRATEGYKEYWORDS: VECTOR, RESISTANT VARIETIES AND PREVENTION
VECTORS
AAP % 10 20 16
Transmission rates (%)
Olive 0 31 7
Polygala 9,5 80 33
N.campestris
P. spumarius
P. italosignus
TO Expand knowledge on spittlebugs as basic information for risk assessment, disease prevention and management
• Phenology, population dynamics and host affiliation
• Feeding behavior and transmission
• Acoustic and chemical communication
• Effectiveness of different control strategies
• P. spumarius : • preferred hosts Asteraceae, Fabaceae, Lamiacea, Rosaceae; • negatively selected Oxalis (Oxalidaceae), Lysimachia (Myrsinaceae), Sherardia (Rubiaceae), Geranium
(Geraniaceae), Papaver (Papaveraceae), Fumaria (Fumariaceae) and Raphanus (Brassicaceae) • Host plant association of later instars nymphs is not fully static.
• Neophilaenus restricted to Poaceae (mainly Avena, Hordeum and Lolium)
• Other Philaenus species with more narrow host range
Phenology, population dynamics and host affiliation: Systematic surveys done using standardized procedures
The phenology and abundance of spittlebugs nymphal and adult stages greatly varyaccording to the environmental, anthropic and climatic conditions
The data on the stage-structured populations of nymphs and adults allows identifying thebest time to apply control measures.
KEY STAGE
SPITTLE = TOO LATE!!!!!!
Life cycle of P. spumarius in Southern Italy
First period of the year when X.fastidiosa can be transmitted toolive by new adults
Feeding behaviour and transmission1) Persistence and transmission dynamics
open field (3 days)
Spittlebug
acquisition(AAP)
037
142128
Differenttimes post AAP (days)
Inoculation(IAP)
The experiment was done twice, in Summer and Autumn
Xf-free adults
olive
Insects maintained on a Xf non-host plants
% IN
FECT
ED P
LAN
TS
0
10
20
30
40
50
60
70
80
90
0 3 7 14 28 56 72 0 3 7 14 28
July 2018 September 2018
% of infected plants - olivo
1) STUDY THE VIBRATIONAL COMMUNICATION
Laser vibrometer
MATING and Courtship – DUET STAGE
Female Calling Signal
Male Courtship Song (MCrS)
Duet(MCrS + Female reply)
Male Courtship Song
S1 S2
Meadow environment: • maximum distance 60-80m in 15 days
Olive grove:• Maximum distance 100-155m in 7-12days• The majority of the marked-insects were captured within 60m
from the release point• In summer population more stationary than autumn (80% of
the marked insects were found within 18 m from the releasepoint)
• Thus, > dispersal capacity in autumn than in summer (favoredby the emergence of the weeds and ground vegetation)
Active movement Mark-release-recapture - Albumin
NO TILLAGE TILLAGE/MULCHING CEREALS
Replacement of the natural vegetationwith non-hosts species
15 meters 15 meters 15 meters
0
10
20
30
40
50
60
70
80
90
100
Abb
ott's
inde
x (%
)
2017 2018
P. spumarius
Hord
eusLoliu
m Tilla
gein
sprin
g
Tilla
gein
win
ter
Efficacy in reducing the spittles
Hord
eus
Loliu
m
Tilla
gein
sprin
g
Tilla
gein
win
ter
- Herbicides (ongoing trials)- Nematodes/fungal entomopath (ongoing trials)- Insecticides
Other applications tested
Treatment/
formulation
Number of nymphs/m2
Rate
(gr or mL/ha)
Before applicationDAT3 DAT7
Untreated check - 136.8 a 236.8 a 152.0 aDELTAMETRIN 800 154.4 a 1.2 c 0.4 d
IMIDACLOPRID 200 1,120 94.0 a 17.6 c 1.2 dBUPROFEZIN 1,500 94.8 a 151.2 ab 40.8 c
Kaolin 40,000 131.2 a 147.2 ab 54.0 cZeolite 6,000 132.8 a 141.2 ab 113.2 b
ORANGE OIL 8,000 132.0 a 112.0 b 72.0 c
Testing different formulations for adultsThese data on efficacy of different chemicals and formulations to control P. spumarius showed that neonicotinoids and pyretroids performed better than the other products.
Neonicotinoidsand
Pyrethroids
Organic: otheractive
principles
Organic (orange oils), high volume of
application
Example of the results in one of the trials
Application of kaolin (repellent) to reduce the spread of the infections in olives
New plantation in 2015
Field experiment
Periodic surveys and sampling
Xf- infections
Testing different colored traps
Almond orchardOlive orchard
Yellow traps gave the best results, those with black circles or lines captured an higher number of Ps but also cicadellidi
SCORRANOLate 2016
OGLIAROLA SALENTINA
LECCINO
LECCINO OGLIAROLA
LECCINOOGLIAROLA
OrganicFarms…
Centennial olive tree in Salento Area: left side Leccino - rigth side Ogliarola(COPERTINO SEPTEMBER 2018)
Grafted part
FIRST PUBLICATION ON «RESISTENT» VARIETIES
Leccino is the third variety for importance in Salento area. It’s an old variety that derives from natural breeding (No GMO). It is well diffused all among Italy and present in different Italian PDO.
1. Leccino2. FS17 o Favolosa3. Frantoio4. Ascolana tenera5. Cipressino6. Coratina7. Picholine8. Carolea9. Nociara10. Termite di Bitetto11. Bella di Cerignola12. Cima di Melfi13. Koroneiki14. Pendolino15. Uggiana16. Peranzana
Xf in Leccino is 100xless concentrated than
di Ogliarola. In FS17 ten times less
than Leccino.
From MAY 2018 it is again possible to make new olive orchards in
infected area
INFECTED AREA
Leccino: a low transmission rate
Leccino has a population ofXylella that is more erratic and100 times lower than Ogliarola.Experimental tests show asignificant reduction intransmission efficiencycompared to Ogliarola
Four hectares are under evaluation for assessing varietal susceptibilityProjects inolved: EFSA (2015), POnTE & XF-ACTORS: 89 different varities
This year other 85 regional varities will be tested in a regional project (REDOXY)
Pathogenic tests with artificial inoculations under
controlled conditions
Summer 2016: olive trees in infected area without symptoms = potential seedlings
Since summer 2016: over 15,000 plants observed –- over 100 asymptomatic seedlings –23 seedlings, already productive- negative results at 3 subsequent analyses (Q-PCR)
From 2017 starting of
morphologicand technologiccharacterisation
Potential results:• New resistant sources or of immunity• New varieties naturally born from local varieties• New potential breeding with local and susceptible varieties
440 different varieties (180 grafted in 2018)3 orchards : 12,5 hectares - 1.000 crops and 6.400 grafted
Cultivars/biotypes of all Italian regions and 15 other countries, advanced cross-breeding selections, 10 wild olive genotypes (wild)
Testing of otherMediterranean
varities
59European Conference on Xylella fastidiosa 2017: finding answers to a global problem
32 days after grafting
9 JUNE 2018
1 year later
NINE SCIENTIFIC PUBLICATION ON ASSOCIATION BETWEEN XF (SUB. PAUCA) AND OLIVE QUICK DECLINE
Scientific Report, hosted 7 works by different research groups on Xylella fastidiosa and 33 in which Xf was in the text
1. Extensive and continuous monitoring
2. Vector control (chemical and mechanic)
3. Elimination of source of infection (uproot infectedcrops)
4. Prohibition of movement of «host and specified»plants (strong restrictions in nurseries)
5. Prohibition of new orchard of hosts in infectedarea (except for resistant species or varieties)
Containment strategy founded on 5 pillars
Monitoring
Vector control
Source of infection
Movem
ent
New
orchards
In absence of a cure for the XF the only way remains prevention !!!!!
• ERADICATION: In continental Spain, in France, in Portugal andin Tuscany it is necessary to eradicate XF (EU Directive onquarantine organisms)
• CONTAINMENT (Apulia, Baleares, Corsica) are INFECTED AREA : contain the expansion decrease the diffusion of XF (EU Directive as well)
AREA DELIMITATION (infected area and buffer area)
UPROOT of infected trees (or crops), vector control, limitation in nursery movements.
General Conclusions
q Awareness that Xylella Fastidiosa (subspecies pauca ST53) it’s the only causes on olive of one of the most serious diseases ever described, as well as (if not more…..) than the famous Pierce disease in USA.
q Several independent introductions took place in Europe in the last century,although there was an obligation to ban the import of citrus and vines.Approach MUST change and the USA standard must be the new rule:“everything is banned except the one that will be authorized” (oppositethan today)
q At the moment infected area are of a limited entity if compared to theEuropean Union. But the movements of goods and persons could lead tonew outbreaks or can be the reason of new infections or recombinationof strains, that could the most terrible option. For this reason the level ofalert must be the highest.
Conclusions for organic farming and olivicolture
q The XF attacks in Apulia with the same intensity organic and conventional olive orchards.
q All the possible differences of managing between organic and conventional farms have beenexamined in a scientific way (soil organic matter, pesticide contaminations, air pollution, watercontent an leaching, rotations scheme and many others).
q Despite these evidences, the Apulia regional authority financed several small “research”projects evoking Organic Agriculture as the real solution to XF on olive trees in Salento area.Today projects are over but no concrete results on the cure was found.
q Resistant and/or tolerant varieties, vector lifecycle investigations, predators and/or naturalenemies, mating disruption and/or mass trapping, seedlings for the identification of oldvarieties with genes of resistance, grafting techniques able to substitute the canopy arekeywords that Organic Agriculture movements are using since the late 80’s.
q We are loosing in Apulia more than 10 million of olive trees on 80 million in 7 years: all ourefforts must be devoted to save the last one.
q In infected area for organic olive trees the most promising methods remains theintroduction of resistant varieties and the vector strategy of control.
December 2013 December 2019
