Control of Xylella fastidiosa in organic olive oil production
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 IDENTIKIT OF AN “UNUSUAL” PATHOGEN
• Xylem-limited bacterium Vessels occlusion: agglomerates • Genetically, morphologically and of cells and biofilm biologically different from other phytopathogenic bacteria
Woody vases
Membrane Water stress symptoms – NOT SPECIFIC Woody • Symptoms are not sufficient to vases define a diagnosis • Active principles MUST reach xylem and MUST be systemic • Root absorption (????) Courtesy: EFSA 2018 IDENTIKIT OF AN “UNUSUAL” PATHOGEN • High variability both genetic and biological
fastidiosa
Different ability in infecting plants, with a wide range od aggressiveness. Toady there is a wide genetic of the bacteria: biology remains a critical and multiplex important point
There is a general correlation between subspecies pauca and crop that can be damaged Europe and Xylella • 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
2015 2018 2016 2013 2018 2017 2018
High risk in Mediterranean areas: temperate with dry-hot summer
Climatic suitability 1 0 Courtesy5 Dr. J. Navas INFECTED INFECTED AREA AREA
2019
From 2013 the «speed» of the XF has been of 30 km/year From Olive Quick Decline Syndrome (OQDS) to OQD Progression of the disease symptoms on the infected trees
Gallipoli, October 2013 Gallipoli, March 2016 30 September 2018
Giant of Alliste (1500 years) 30 September 2014
First symptoms (north sided on the upper part) 2016 near Gallipoli (South Salento ) 2019 near Gallipoli (South Salento ) France outbreaks as determined by analyses of samples taken in the frame of the National survey plan and control of imported plants Corsica region Update: July 2018 -354 outbreaks -36 plant species Eradication -80% focolai - P. myrtifolia -6 outbreaks between PACA region 700m e 950m over the -67 foci sea level -23 plant species 2017 - containment
Positive Undetermined
Positive Undetermined Positive Undetermined
http://www.corse-du-sud.gouv.fr/xylella-fastidiosa-une-menace-qui-demande-une-a1409.html http://www.alpes-maritimes.gouv.fr/Politiques-publiques/Securite-et-protection-de-la-population/Xylella-Fastidiosa/Communiques Acacia dealbata Link Acer pseudoplatanus L. Positive samples in Corsica (%) Host plants of Xf in France Anthyllis hermanniae L. Artemisia arborescens L. Asparagus acutifolius L. Calicotome villosa (Poiret) Link 33% + in PACA Metrosideros Cercis silicastrum Polygala myrtifolia excelsa Cistus creticus L. Euryops chrysanthemoides Artemisia Medicago sativa L. arborecens Cistus monspeliensis L. 10% Cistus salviifolius L. Westringia longifolia Coronilla valentina L. Acer Cytisus scoparius (L.) Link Lavendula sp.. pseudoplatanus Cytisus sp. Helichrysum Cytisus villosus L italicum Genista x spachiana (syn. Cytisus racemosus Broom) Pelargonium Quercus Genista corsica (Loisel.) DC. graveolens suber Genista ephedroides DC. Genista x spachiana (syn. Cytisus racemosus Broom) Common to Mediterranean Hebe sp. scrubs Prunus Coronilla Helichrysum italicum (Roth) G. Don 13% valentina Spartium junceum cerasifera Lavandula angustifolia Mill. 10% Lavandula dentata L. Lavandula sp. Calicotome Rosa x villosa Lavandula stoechas L. CistusNotsp. a realfloribunda epidemic situation but a “silent”Lavandula x allardii infection.(syn. Lavandula x heterophyllaThe question) is what could happen Lavandula x intermedis Regional economic impact in a near future of globalisation andMetrosideros taking excelsa into Sol. ex account Gaertn. the European genetic diversity Asparagus Myrtus communis L. Myrtus communis acutifolius Acacia dealbata Nerium oleanderof XF? Pelargonium graveolens L'Hér Nerium Phagnalon saxatile (L.) Cass. oleander Genista Anthyllis Polygala myrtifolia L. 26% Hebe sp. hephredoides hermaniae Prunus cerasifera Ehrh. Prunus dulcis (Mill.) D.A Webb Quercus suber L. Rosa canina L. Rosmarinus Phagnalon Rosmarinus officinalis L. Cytisus racemosus officinalis Prunus dulcis saxatile Spartium junceum L. 22% Situation of Xylella fastidiosa in the Balearic islands
Mallorca 476(+) Menorca Fig tree 4% Olive 8% 139 (+) grapevine 14% Olive 41% Wild olive 26% Wild olive 46% Almond 38% Mallorca
Xf subsp. multiplex ST81 Xf subsp. multiplex ST81 Xf subsp. multiplex ST7 Xf subsp. fastidiosa ST1
Total positives = 740 (February 2019) & 21 host plants
Ibiza 228 (+) Olive 9% Wild olive 81%
Xf subsp. pauca ST80 Situation of Xylella fastidiosa in the Balearic islands Ø Host plants: 21 species of crops, ornamentals and natural vegetation Grapes Almond Cherry Plum fastidiosa ST1 fastidiosa ST1 /multiplex ST7,ST81 fastidiosa ST1 multiplex ST81
Olive Oleaster Fig Walnut multiplex ST81/pauca ST80 multiplex ST81/pauca ST80 multiplex ST81 Subsp. fastidiosa ST1 Situation of Xylella fastidiosa in the Balearic islands Olive (Olea europea var. europaea) Xylella fastidiosa subsp. multiplex Situation of Xylella fastidiosa in the Balearic islands Olive (Olea europea var. europaea) Xylella fastidiosa subsp. multiplex Situation of Xylella fastidiosa in the Balearic islands Almond (Prunus dulcis) Xylella fastidiosa subsp. fastidiosa
Foto: Blanca B Landa Foto: Blanca B Landa
Foto: Andreu Juan
Foto: Andreu Juan Situation of Xylella fastidiosa in the Balearic islands Almond (Prunus dulcis) Xylella fastidiosa subsp. fastidiosa Situation of Xylella fastidiosa in the Balearic islands Grapes (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: 01/09/2017 Starting date: 01/11/2015 Starting date: 01/11/2016 Ending date : 31/08/2021 Ending date: 31/10/2019 Ending date : 31/10/2020 Exchange scientific capacities among Xylella fastidiosa and its Research project to improve prevention, European and third countries, strengthen vectors in olive, grapevine, early detection and control of Xylella the knowledge and the know-how on Xf in citrus, stone fruit, fastidiosa through the establishment of a third countries, raise awareness in ornamentals and landscape multidisciplinary research program. relation to Xf impacts and risks upon its trees of high socio-economic establishment importance. XF Actors: Xylella Fastidiosa Active Containment Through a multidisciplinary-Oriented Research Strategy
The overall goal of the research program is to develop scientific knowledge on the pathogenicity, transmissibility and host susceptibility to the Xf strains recovered in the EU outbreaks, toward the implementation of tools for pest risk assessment, for prevention and reduction of the impact of the Xylella-induced diseases.
The research actions are complementary to those carried out under the Project POnTE thus ensuring effective cooperation and continuity with currently ongoing efforts. XF Actors project: results achieved so far PUBLICATIONS
- 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 from different 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 Southern Italy (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 implementation of integrated and organic control strategies BACTERIA TRANSMISSION ON SHORT AND LONG DISTANCE
IDENTIFICATION AND EVALUATION OF RISK REDUCTION OPTIONS TO REDUCE THE PROBABILITY OF ENTRY NoAND seeds SPREAD - No roots contact - No cutting tools
Xylella Fruits fastidiosa pathways Obliged parasite Seeds Infectious only through insect vectors Crop or part of crops Detached wood
Courtesy EFSA
Cut flowers
25 IDENTIKIT OF AN “UNUSUAL” PATHOGEN • 560 host species at world level Vectors are xylem-sap feeders • Only sometimes very critical damages NO SPECIFICITY • Crops reply in a different way linked to immunity, resistance, susceptibility
Atypical "persistent" transmission: bacteria it’s alive only in the internal part of the cuticle of the mouthpart Vector lose infectivity at each developmental stage: adults maintain Inspections are difficult and much more alive bacteria for all their lifetime controls or strategies !!!!!!!!! XF HOSTS IDENTIFIED IN APULIA
1. Acacia saligna (Labill.) 20. Myrtus communis L. 2. Amaranthus spp. 21. Myoporum insulare R. Br. 3. Asparagus acutifolius L. 22. Nerium oleander L. 4. Catharanthus 23. Olea europaea L. 5. Chenopodium album L. 24. Pelargonium x fragrans • Olea europaea most 6. Cistus creticus L. 25. Phillyrea latifolia L. common host in Apulia 7. Dimorphoteca fruticosa L. 26. Polygala myrtifolia L. 8. Dodonaea viscosa Jacq. 27. Prunus avium (L.) L. • Crop death for Oilves, 9. Eremophila maculata F. Muell. 28. Prunus dulcis (Mill.) D.A. 10. Erigeron sumatrensis Retz. 29. Rhamnus alaternus L. Polygala and Thorntree 11. Erigeron bonariensis L. 30. Rosmarinus officinalis L. • But the level of 12. Euphorbia terracina L. 31. Spartium junceum L. 13. Euphorbia chamaesyce L. 32. Vinca damages depends on 14. Grevillea juniperina L. 33. Westringia fruticosa (Willd.) the environmental 15. Heliotropium europaeum L. 34. Westringia glabra L. 16. Hebe spp. conditions 17. Laurus nobilis L. Symptomless hosts 18. Lavandula angustifolia Mill. 19. Lavandula stoechas L. Crop species 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
Evidences: Costa Rica similitudes - 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
NO Susceptible variety (Ogliarola) July 2016 December 2017 Xylella
Other crops
• Green points: no symptoms • Red points: big symptoms
Vectors catchment starting form the centre of one olive orchard = 100-155 meters in 7-12 days Apulia situation for Olea Euroepa: a phytopatological apocalypse
A combination of different factors were the reason for the epidemic in Salento area
Climatic conditions extremely favorable
Olea europea extremely susceptible to Xylella fastidiosa
Olive oil crop evergreen
In Salento only two varieties (Cultivar: Ogliarola and Cellina) OLIVE TREES IN SALENTO A bacterium strain very aggressive on olive trees and also on other 32 different species Vector population extremely high Canopy very wide. In summer the Olive trees in Salento area are almost everywhere ideal place for the insect. Many without any interruption puncture = very high level of bacteria «inside» the vector Crops in which no Xf bacteria was found
Vineyards Death Olive CITRUS 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 DEVELOPMENT THERE ARE NO ACTIVE PRINCIPLES THAT HAVE EFFICACY AGAINST XF
IS THERE A CURE? NO BUT THERE CAN BE A STRATEGY KEYWORDS: VECTOR, RESISTANT VARIETIES AND PREVENTION VECTORS
N. P. P. campestris spumarius italosignus
AAP % 10 20 16
Transmission rates (%) Olive 0 31 7 Polygala 9,5 80 33 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 vary according to the environmental, anthropic and climatic conditions The data on the stage-structured populations of nymphs and adults allows identifying the best time to apply control measures. SPITTLE = TOO LATE!!!!!! KEY STAGE Life cycle of P. spumarius in Southern Italy
First period of the year when X. fastidiosa can be transmitted to olive by new adults Feeding behaviour and transmission 1) Persistence and transmission dynamics % of infected plants - olivo
90 Inoculation (IAP) 80 acquisition Different 70 (AAP) times post AAP (days) 60Spittlebug Insects 50 maintained on a Xf non- 0 40 3 olive host plants Xf-free 7 30 adults open field (3 days) 14
20 21
% INFECTED PLANTS % INFECTED 28 10
0 0 3 7 14 28 56 72 0 3 7 14 28 The experimentJuly 2018 was done twice, in Summer Septemberand Autumn 2018 1) STUDY THE VIBRATIONAL COMMUNICATION
Laser vibrometer MATING and Courtship – DUET STAGE
Male Courtship Song (MCrS)
Duet Female Calling Signal (MCrS + Female reply) Male Courtship Song
S1 S2 Active movement Mark-release-recapture - Albumin
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 release point) • Thus, > dispersal capacity in autumn than in summer (favored by the emergence of the weeds and ground vegetation) Replacement of the natural vegetation with non-hosts species
NO TILLAGE TILLAGE/MULCHING CEREALS
15 meters 15 meters 15 meters Efficacy in reducing the spittles 100
90 P. spumarius
80
70
60 spring 50 in
40 winter Tillage in 30 spring winter Lolium Abbott's index (%) in in Lolium Tillage 20 Hordeus Hordeus Tillage
10 Tillage
0 2017 2018 Other applications tested
- Herbicides (ongoing trials) - Nematodes/fungal entomopath (ongoing trials) - Insecticides
Treatment/ Number of nymphs/m2 Rate Before application formulation DAT DAT (gr or mL/ha) 3 7 Untreated check - 136.8 a 236.8 a 152.0 a DELTAMETRIN 800 154.4 a 1.2 c 0.4 d IMIDACLOPRID 200 1,120 94.0 a 17.6 c 1.2 d BUPROFEZIN 1,500 94.8 a 151.2 ab 40.8 c Kaolin 40,000 131.2 a 147.2 ab 54.0 c Zeolite 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 adults These data on efficacy of different chemicals and formulations to control P. spumarius showed that neonicotinoids and pyretroids performed better than the other products. Example of the results in one of the trials
Neonicotinoids and Pyrethroids
Organic (orange oils), high volume of application
Organic: other active principles Application of kaolin (repellent) to reduce the spread of the infections in olives Xf- infections New plantation in 2015
Periodic surveys and sampling
Field experiment Testing different colored traps
Almond orchard Olive orchard
Yellow traps gave the best results, those with black circles or lines captured an higher number of Ps but also cicadellidi OGLIAROLA SALENTINA SCORRANO Late 2016
LECCINO LECCINO OGLIAROLA Organic Farms…
OGLIAROLA LECCINO Centennial olive tree in Salento Area: left side Leccino - rigth side Ogliarola Grafted part (COPERTINO SEPTEMBER 2018) FIRST PUBLICATION ON «RESISTENT» VARIETIES
1. Leccino INFECTED 2. FS17 o Favolosa AREA 3. Frantoio 4. Ascolana tenera 5. Cipressino From MAY 2018 it is 6. Coratina again possible to make 7. Picholine new olive orchards in 8. Carolea infected area 9. Nociara 10. Termite di Bitetto 11. Bella di Cerignola Xf in Leccino is 100x 12. Cima di Melfi less concentrated than 13. Koroneiki di Ogliarola. 14. Pendolino In FS17 ten times less 15. Uggiana than Leccino. 16. Peranzana
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. Leccino: a low transmission rate
Leccino has a population of Xylella that is more erratic and 100 times lower than Ogliarola. Experimental tests show a significant reduction in transmission efficiency compared to Ogliarola Four hectares are under evaluation for assessing varietal susceptibility Projects 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 From 2017 starting of morphologic and technologic characterisation
Potential results: • New resistant sources or of immunity • New varieties naturally born from local varieties • New potential breeding with local and susceptible varieties Since summer 2016: over 15,000 plants observed – - over 100 asymptomatic seedlings –23 seedlings, already productive - negative results at 3 subsequent analyses (Q-PCR) Testing of other Mediterranean varities
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) 9 JUNE 2018
32 days after grafting 1 year later
European Conference on Xylella fastidiosa 2017: finding answers to a global problem 59 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 Containment strategy 2. Vector control (chemical and mechanic) founded on 5 pillars
3. Elimination of source of infection (uproot infected crops)
4. Prohibition of movement of «host and specified» Sourceinfection of New plants (strong restrictions in nurseries) control Vector Monitoring Movement orchards 5. Prohibition of new orchard of hosts in infected area (except for resistant species or varieties) In absence of a cure for the XF the only way remains prevention !!!!!
• ERADICATION: In continental Spain, in France, in Portugal and in Tuscany it is necessary to eradicate XF (EU Directive on quarantine 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” (opposite than today) q At the moment infected area are of a limited entity if compared to the European Union. But the movements of goods and persons could lead to new outbreaks or can be the reason of new infections or recombination of strains, that could the most terrible option. For this reason the level of alert 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 been examined in a scientific way (soil organic matter, pesticide contaminations, air pollution, water content 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 natural enemies, mating disruption and/or mass trapping, seedlings for the identification of old varieties with genes of resistance, grafting techniques able to substitute the canopy are keywords 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 our efforts must be devoted to save the last one. q In infected area for organic olive trees the most promising methods remains the introduction of resistant varieties and the vector strategy of control. December 2013 December 2019 THANKS FOR YOUR ATTENTION
VINCENZO VERRASTRO CIHEAM BARI [email protected]