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The vector‐borne bacterium Xylella fastidiosa(Wells and Raju) causes several serious diseases to plants. Recently, different subspecies of X. fastidiosa were reported in some European countries. The risk of the bacterium’s spread on the entire European territory is very high; therefore, it has been added into the priority pest list (2019/1702/EU Regulation). The main purposes of this work were to verify the presence of potential vectors in areas at a high risk of introduction in Tuscany and to ascertain the presence of X. fastidiosa in these insect vectors. Over 4,000 Auchenorrhyncha were collected and analysed from 2015 to 2019. Among the xylem sap-feeder putative vectors, most of the insects collected belonged to the family Aphrophoridae, but also many species of leafhopper were identified. Overall, in Tuscany four species were the most represented: Philaenus spumarius(L.), Cicadella viridis(L.), Synophropsis lauri (Horvath) and Neophilaenus campestris(Fallen).In 2018 an outbreak of X. fastidiosa subsp. multiplex was reported in Monte Argentario (Grosseto province, Tuscany). In 2019 X. fastidiosa subspecies multiplex ST 87 was detected in seven P. spumarius and three N. campestris collected from the infected area.

[eng] Xylella fastidiosa (Wells et al. 1987) is a gram-negative Gammaproteobacterium pathogen of plants and limited to the xylem conduits. The bacterium is capable to infect more than 600 different plant species causing several types of diseases (i.e., Pierce's disease, citrus variegated chlorosis, leaf scorch). It is transmitted by xylem sap feeder insects from the order Hemiptera and suborder Cicadomorpha. In Europe, the major vectors belong to the family Aphrophoridae. Xylella fastidiosa was detected in 2013 in Italy and in 2016 in the Balearic Islands. The general objectives of the thesis are i) macrocosm and microcosm studies of the vectors in the major agrosystems of the Balearic Islands; ii) Prevalence of X. fastidiosa in the vectors and vectorial capacity of potential vectors; iii) Test a cultural method against vectors. Nine organic farms (three olive, three vineyards and three almond) were selected in Majorca for conducting annual monitoring. The islands of Minorca, Ibiza and Formentera were sampled twice a year (summer and autumn). Insects were collected biweekly in each plot in Majorca by using a sweep net for adults and a wood frame of 0.25 m2 for nymphs. In the microcosm study, 50 cages containing one male and one female of Philaenus spumarius, one plant species per cage (Rosmarinus officinalis, Mentha x piperita, Ocimum basilicum, Pistacia lentiscus or Lavandula dentata) and substrate for oviposition (straw) were placed at field conditions. Insects were placed inside the cages from September to November, then cages were checked to detect egg batches and monitor nymphs’ development. From the adults collected from the field, the prevalence of X. fastidiosa was determined by qPCR. In a first approach, field collected insects were caged for the vector competence studies with X. fastidiosa free plants of Medicago sativa for 96 h. Then, insects were analysed by qPCR. Samples taken from plants were analysed 15, 30, 45 and 60d post inoculation. Moreover, in a second approach, nymphs were collected from the field, reared until adults and put in contact with vine and almond X. fastidiosa infected trees for 96 h acquisition access period. Then, adults were in contact with alfalfa plants for 96 h inoculation access period. Both adults and alfalfa plants were analysed by qPCR. Finally, for the mechanical control method test, the ground cover vegetation was mowed or tilled from olive and vineyard farms to assess the control of nymphs of X. fastidiosa vectors. Philaenus spumarius and Neophilaenus campestris (Aphrophoridae) were recorded in the Balearic Islands. Results indicated that nymphs were present from early-May to early-June. Philaenus spumarius nymphs were more abundant in the cover vegetation of olive crops, followed by vineyard and almond ones, while N. campestris was more abundant in olive and almond. The highest abundance of P. spumarius adults was recorded in May and October in the cover vegetation. Presence of adults increased in trees in June, while presence in the border vegetation of the crop increased in August and decreased around October. In the case of N. campestris, the highest abundance of adults was detected in the cover plants in May and November, however its presence in trees and border vegetation can be considered negligible. The prevalence of X. fastidiosa from the insects collected (1059 insects analysed) was 22.8 %; P. spumarius showed a prevalence of 23.6 % and N. campestris of 20.8 %. The island with the highest prevalence was Majorca reaching the 24 %, followed by Menorca (21.5 %) and Ibiza (21 %), Formentera remained free of X. fastidiosa. Xylella fastidiosa subsp. fastidiosa and multiplex were detected in insects form Majorca, X. fastidiosa subsp. multiplex was determined in Minorca and X. fastidiosa subsp. pauca was identified in Ibiza. The first approach of transmission test showed a 16.3 % of positive insects (N = 264). Inoculation to M. sativa was confirmed since the plants were positive by qPCR 15, 30, 45 and 60 days after inoculation. In the second approach, P. spumarius acquired the bacteria from almond (34.4 % of insects) and from vineyard (87.7 %). Only insects that acquired the bacterium from almond, transmitted X. fastidiosa to alfalfa plants. Results on the mechanical control test showed that mowing and tilling affect nymphs of X. fastidiosa vectors by reducing its density significantly below that of control zones. [cat] Xylella fastidiosa (Wells et al. 1987) és un fitopatogen gramnegatiu que pertany als Gammaproteobacteris i només envaeix els conductes del xilema. El bacteri és capaç d'infectar més de 600 espècies vegetals diferents causant diversos tipus de malalties (com per exemple, la malaltia de Pierce, la clorosi variegada dels cítrics o el Síndrome del decaïment sobtat de l’olivera). Es transmet per insectes de l'ordre dels hemípters i del subordre dels cicadomorfs que s’alimenten del fluid xilemàtic. A Europa, els principals vectors de propagació pertanyen a la família Aphrophoridae. Xylella fastidiosa es va detectar a Europa l’any 2013 i al 2016 a les Illes Balears. Els objectius generals de la tesi són: i) Estudi del macrocosmos i microcosmos dels vectors en els agrosistemes més rellevants de les Illes Balears; ii) Prevalença de X. fastidiosa als vectors i capacitat vectorial dels potencials vectors; iii) Assaig d’un mètode de control cultural enfront els vectors. S'han seleccionat a Mallorca nou explotacions ecològiques (tres d'olivera, tres de vinya i tres d'ametllers) per fer un seguiment anual. Les illes de Menorca, Eivissa i Formentera es van mostrejar dos cops l'any (estiu i tardor). Els insectes es van recollir quinzenalment a cada parcel·la de Mallorca, els adults mitjançant màniga entomològica i les nimfes amb un marc de fusta de 0,25 m2. A l'estudi del microcosmos, es van col·locar al camp 50 gàbies que contenien un mascle i una femella de P. spumarius, una planta per gàbia (Rosmarinus officinalis, Mentha x piperita, Ocimum basilicum, Pistacia lentiscus o Lavandula dentata) i substrat per a l'oviposició (palla). Els insectes es van col·locar dins de les gàbies de setembre a novembre, després es van comprovar per detectar postes d'ous i controlar el desenvolupament de les nimfes. A partir dels vectors adults recollits al camp, es va determinar la prevalença de X. fastidiosa mitjançant qPCR. Per als estudis de competència vectorial, es van realitzar dos tipus d'assajos. Per al primer tipus, els insectes adults recollits al camp es van posar en contacte amb Medicago sativa lliures de X. fastidiosa durant 96 h. A continuació, es van analitzar els insectes mitjançant qPCR. Les mostres de plantes es van analitzar els 15, 30, 45 i 60 dies després de la inoculació. Per al segon tipus, es van recollir nimfes del camp, es van criar fins a adults i es van posar en contacte amb arbres de vinya i ametller infectats de X. fastidiosa durant 96 h. Aleshores, els adults es van posar en contacte amb plantes d'alfals durant un període d'inoculació de 96 h. Tant les plantes d’alfals com els vectors es van analitzar mitjançant qPCR. Finalment, per a l’assaig del mètode de control mecànic, es va segar o llaurar la vegetació de la coberta del sòl de granges d’olivera i vinya per avaluar el control de les nimfes dels vectors X. fastidiosa. A les Illes Balears s’han detectat els insectes vectors P. spumarius i N. campestris (Aphrophoridae). Les nimfes estaven presents des de principis de maig fins a principis de juny. Les nimfes de P. spumarius eren més abundants a la vegetació de coberta dels cultius d'olivera, seguides de vinya i ametller, mentre que N.campestris era més abundant en olivera i ametller. La major abundància d'adults de P. spumarius es va registrar a maig i octubre a la vegetació de coberta. La presència d'adults va augmentar als arbres al juny, mentre que la presència a la vegetació de vora del cultiu va augmentar a l'agost i va disminuir cap a l'octubre. En el cas de N. campestris, la major abundància d'adults es va detectar a les plantes de coberta durant els mesos de maig i novembre, però la seva presència en arbres i vegetació de vorera es pot considerar insignificant. La prevalença de X. fastidiosa dels insectes recollits a camp va ser del 22.8 %, P. spumarius va mostrar una prevalença del 23.6 % i N. campestris del 20.8 %. L'illa amb major prevalença va ser Mallorca arribant al 24 %, seguida de Menorca (21.5 %) i Eivissa (21 %), Formentera es va mantenir lliure de X. fastidiosa. Xylella fastidiosa subsp. fastidiosa i multiplex es va detectar a insectes capturats a Mallorca, X. fastidiosa subsp. multiplex a Menorca i X. fastidiosa subsp. pauca a Eivissa. El primer tipus de prova de transmissió va mostrar un 16.3 % d'insectes positius (N = 264). Es va confirmar la inoculació a M. sativa ja que les plantes eren positives per qPCR 15, 30, 45 i 60 dies després de la inoculació. En el segon tipus de prova, P. spumarius va adquirir el bacteri de l'ametller (34.4 % dels insectes) i de la vinya (87.7 %), i, només d'insectes d'ametller, es va confirmar la inoculació a plantes d'alfals. Els resultats de la prova de control mecànic van mostrar que la sega i el conreu afecten a les nimfes de vectors de X. fastidiosa reduint la seva densitat significativament a les zones de control. [spa] Xylella fastidiosa (Wells et al. 1987) es una Gammaproteobacteria gramnegativa patógena que invade los conductos del xilema de las plantas. La bacteria es capaz de infectar a más de 600 especies de plantas diferentes y causar varios tipos de enfermedades (p.ej. la enfermedad de Pierce, la clorosis variegada de los cítricos y el síndrome del declive rápido del olivo). Se transmite mediante insectos que se alimentan de la savia del xilema perteneciente al orden Hemiptera y el suborden Cicadomorpha. En Europa, los principales vectores de propagación pertenecen a la familia Aphrophoridae. Xylella fastidiosa se detectó en 2013 en Europa y en 2016 en las Islas Baleares. Los objetivos generales de la tesis son: i) estudio del macrocosmos y microcosmos en los agrosistemas más relevantes de las Islas Baleares; ii) Prevalencia de X. fastidiosa en los vectores y capacidad vectorial de los potenciales vectores; iii) Ensayo de un método de control cultural frente a los vectores. Se seleccionaron nueve fincas ecológicas (tres de olivo, tres de viña y tres de almendro) en Mallorca para realizar un seguimiento anual. Las islas de Menorca, Ibiza y Formentera se muestrearon dos veces al año (verano y otoño). Los insectos se recolectaron quincenalmente en cada parcela de Mallorca utilizando una manga entomológica para capturar los adultos y un marco de madera de 0,25 m2 para ninfas. En el estudio de microcosmos, se colocaron en campo 50 jaulas que contenían un macho y una hembra de P. spumarius, una planta por jaula (Rosmarinus officinalis, Mentha x piperita, Ocimum basilicum, Pistacia lentiscus o Lavandula dentata) y sustrato para la oviposición (paja). Los insectos se colocaron dentro de las jaulas de septiembre a noviembre, luego se revisaron para detectar puestas de huevos y monitorear el desarrollo de las ninfas. De los adultos recolectados en el campo, se determinó la prevalencia de X. fastidiosa por qPCR. Para los estudios de competencia vectorial, se llevaron a cabo dos tipos de ensayos. Para el primer tipo, los insectos recolectados en el campo se pusieron en contacto con plantas de Medicago sativa libres de X. fastidiosa de durante 96 h. Luego, los insectos fueron analizados por qPCR. Las muestras tomadas de las plantas se analizaron 15, 30, 45 y 60 días después de la inoculación. Para el segundo tipo, las ninfas se recolectaron del campo, se criaron hasta adultos y se pusieron en contacto con árboles de almendro y vid infectados con X. fastidiosa durante un periodo de adquisición de 96 h. Pasado este tiempo, los adultos estuvieron en contacto con las plantas de alfalfa durante un período de inoculación de 96 h. Tanto los adultos como las plantas de alfalfa se analizaron mediante qPCR. Finalmente, para la prueba del método de control mecánico, se segó o labró la vegetación de la cubierta vegetal de fincas de olivos y viñedos para evaluar el control de las ninfas de los vectores X. fastidiosa. En las Islas Baleares se han encontrado dos especies de vectores, P. spumarius y N. campestris (Aphrophoridae). Las ninfas estuvieron presentes desde principios de mayo hasta principios de junio. Las ninfas de P. spumarius fueron más abundantes en la cubierta vegetal de los cultivos de olivo, seguidas de las de vid y almendro, mientras que N. campestris fue más abundante en el olivo y el almendro. La mayor abundancia de adultos de P. spumarius se registró en mayo y octubre en la cubierta vegetal. La presencia de adultos aumentó en los árboles en junio, mientras que la presencia en la vegetación de borde del cultivo fue mayor en agosto y disminuyó en octubre. En el caso de N. campestris, la mayor abundancia de adultos se detectó en la cubierta en mayo y noviembre, sin embargo, su presencia en árboles y vegetación de borde puede considerarse negligible. La prevalencia de X. fastidiosa en los insectos recolectados fue de 23 %, P. spumarius mostró una prevalencia de 23.8 % y N. campestris de 20.8 %. La isla con mayor prevalencia fue Mallorca con un 24 %, seguida de Menorca (21.5 %) e Ibiza (21 %), Formentera se mantuvo libre de X. fastidiosa. Xylella fastidiosa subsp. fastidiosa y multiplex se detectó en insectos capturados en Mallorca, X. fastidiosa subsp. multiplex en Menorca y X. fastidiosa subsp. pauca en Ibiza. El primer tipo de prueba de transmisión mostró un 16.3 % de insectos positivos (N = 264). Se confirmó la inoculación a M. sativa ya que las plantas fueron positivas por qPCR a los 15, 30, 45 y 60 días después de la inoculación. En el segundo tipo, P. spumarius adquirió la bacteria del almendro (34.4 % de los insectos) y del viñedo (87.7 %), y, solo de los insectos del almendro, se confirmó la inoculación a las plantas de alfalfa. Los resultados de la prueba de control mecánico mostraron que la siega y la labranza afectan a las ninfas de los vectores X. fastidiosa al reducir su densidad de forma significativa a las zonas de control, disminuyéndola.

El conocimiento de la biología y dinámica poblacional de los insectos vectores de la bacteria fitopatógena Xylella fastidiosa Wells et al., 1987, es fundamental para llevar a cabo un adecuado control de las enfermedades que produce en plantas cultivadas, por medio del manejo de dichos vectores. En la Comunidad Valenciana, en la Zona Demarcada por presencia de la bacteria localizada en la provincia de Alicante, Philaenus spumarius (Linnaeus, 1758), Neophilaenus campestris (Fallén, 1805) y Neophilaenus lineatus (Linnaeus, 1758) han evidenciado portar la bacteria, si bien solo las dos primeras especies son vectores reconocidos en Europa.

International audience; The bacterium Xylella fastidiosa represents a potential risk to the Moroccan flora. For this reason, several surveys were conducted in 2019 and 2020 to assess its occurrence and to establish an inventory of its potential insect vectors with emphasis on their characterization and importance from 85 sites in 25 provinces across the country. Using a sweeping net, 2604 specimens belonging to the Auchenorrhyncha suborder (Hemiptera) were collected. A total of 213 samples from different crops, including two ornamental species Nerium oleander and Polygala spp., were sampled and tested for the presence of X. fastidiosa by ELISA and PCR techniques during the same period within the same surveyed provinces (plus two additional ones, i.e. 27 provinces). Aphrophoridae species were mainly located in the northern part of Morocco where five potential insect vectors occur, namely Philaenus tesselatus, P. maghresignus, Philaenus sp., Neophilaenus campestris and N. lineatus. Philaenus tesselatus was the most important spittlebug recorded with uneven occurrence throughout the country. Philaenus spumarius has not been found in the present surveys which could indicate that it has been replaced by P. tesselatus. Therefore, the latter should be considered as the main potential insect vector of X. fastidiosa in Morocco. Current status and importance of spittlebugs, sharpshooter-leafhoppers, treehoppers and planthoppers are given. ELISA and PCR results did not show any positive results, which may be seen as good news indicating that X. fastidiosa was not found in Morocco. Regarding occurrence and importance of P. tesselatus in Morocco, pest risk analysis of X. fastidiosa in the country should be revised. Our findings highlight the factors that would contribute to the active spread of the X. fastidiosa once introduced into the country.; La bactérie Xylella fastidiosa représente un risque potentiel pour la flore au Maroc. Pour cette raison, des prospections ont été menées entre 2019 et 2020 pour évaluer sa présence et établir un inventaire exhaustif de ses insectes vecteurs potentiels tout en mettant l’accent sur leurs caractéristiques et leur importance dans 85 sites au niveau de 25 provinces à travers le pays. À l’aide d’un filet fauchoir, 2604 spécimens appartenant au sous-ordre des Auchenorrhyncha (Hemiptera) ont été collectés. Un total de 213 échantillons provenant de différentes cultures, dont deux espèces ornementales, Nerium oleander et Polygala spp., ont été échantillonnées et testées pour la présence de X. fastidiosa par les techniques d’ELISA et PCR, et ce au cours de la même période dans les mêmes zones étudiées (plus deux autres supplémentaires, soit 27 provinces). Les espèces d’Aphrophoridae étaient principalement localisées dans la partie nord du Maroc où se trouvent cinq insectes vecteurs potentiels : Philaenus tesselatus, P. maghresignus, Philaenus sp., Neophilaenus campestris et N. lineatus. Philaenus tesselatus était le plus important vecteur recensé avec une présence inégale dans tout le pays. Philaenus spumarius n’a pas été trouvé lors des observations actuelles ce qui pourrait indiquer qu’il ait été remplacé par P. tesselatus. Ce dernier devrait donc être considéré comme le principal insecte vecteur potentiel de X. fastidiosa au Maroc. L’état actuel et l’importance des insectes appartenant aux familles Aphrophoridae, Cicadellidae, Membracidae, Issidae, Dictyopharidae et Tettigometridae sont indiqués. Les résultats d’ELISA et de PCR n’ont montré aucun résultat positif, ce qui peut être considéré comme une bonne nouvelle indiquant que X. fastidiosa n’a pas été trouvée au Maroc. Tenant en compte la présence et l’importance de P. tesselatus au Maroc, l’analyse du risque phytosanitaire de X. fastidiosa au Maroc devrait être revue. Nos données mettent en évidence les facteurs qui pourraient contribuer à la propagation active de X. fastidiosa une fois introduite dans le pays.

[EN] Neophilaenus campestris is one of the spittlebugs (Hemiptera: Cercopoidea) able to transmit Xylella fastidiosa to olive trees. Considering its vector ability and the wide distribution of this species in Spain, N. campestris should be considered a serious threat to key crops such as olive, almonds and grapevines. Migration and dispersal abilities of insect vectors have profound implications in the spread of vector-borne diseases. Thus, knowledge on the dispersal ability of N. campestris is essential to model, predict and limit the spread of the diseases caused by X. fastidiosa. A mass-mark-recapture technique was developed to track between-field movements of N. campestris during its late spring migration from the ground cover grasses within olive groves to sheltered areas dominated by pine trees. The fluorescent dust used for marking did not affect the survival nor the flying ability of N. campestris. Spittlebug adults captured in olive groves during late spring were dusted with fluorescent colours and released in different locations. Six recapture samplings were performed 23¿42 days after release in 12 different sites located within a maximum distance of 2.8 km from the release point. Results indicated that N. campestris was able to disperse a maximum distance of 2,47 m in 35 days. Furthermore, flight mill studies showed that N. campestris was able to fly long distances, reaching 1.4 km in an 82-min single flight. Altogether, our findings suggest that eradication measures are of limited value because vectors are able to disperse rapidly over distances much longer than expected., Ministerio de Ciencia e Innovacion, Grant/Award Number: AGL2017-89604--R and PRE2018-083307; Comunidad de Madrid, Grant/Award Number: FP19-XYLELLA

In the last 5 years several trials have been developed under field and semifield conditions in Apulia (southern Italy) to test the effectiveness of different strategies to control the populations of Philaenus spumarius (Ps) and Neophilaenus campestris (Nc) in olive groves. Trials were optimized based on the outcomes (biology, host preference and population dynamics) of a multiyear monitoring program. It is well estabhlished that mechanical interventions for removing the ground vegetation in spring, is one of the best and environmentally sustainable strategies against juveniles. However, we demonstrated that the timing for these interventions is critical to get high suppression efficiency and should be defined locally based on the microclimatic conditions. Nevertheless, a wide range of alternative strategies have been tested: mulching, pyroherbicides, applications of herbicides/insecticides, replacement of the natural ground vegetation, reaching in some cases mortality rates close to 100%. Sowing gramineous (negatively selected by Ps) can contribute to reduce Ps nymphs but not Nc. Among insecticides, neonicotinoids and pyrethoids showed the highest efficacy in the control of juveniles of both species, while other products (i.e. buprofenzin , orange essential oil, kaolin and zeolite) contributed to reduce the nymphs population but showed lower effectiveness. With regard to adults, insecticides are so far the only practical option available. Neonicotinoids and pyrethroids showed the highest efficacy and persistence up to 15-20 and 20-25 days after treatment, respectively. High values of mortality and persistence were obtainded in trials where cyantraniliprole was used. Organophosphate insecticides yielded lower mortality rates or inconsistent results. Good knockdown effect was recorded using spinosad, spinetoram, abamectina and orange essential oil, with a persistence up to 7 days for spinetoram, but with no-persistence in other insecticides tested. Other insecticides, i.e spirotetramat, flonicamid, pymetrozine, buprofenzin, natural pyrethrin and azadirachtin, did not cause significant mortality compared to the untreated controls. As for the juveniles, investigations on the population dynamics in olive groves and other crops, allowed to identify the best timing for insecticides applications. All togheter, the data gathered from the different control strategies tested allowed to define a set of recommended interventions for reducing juvenile and adult spittlebugs.

Monitoring spittlebugs has become crucial for the implementation of preventive measures against the spread of Xylella fastidiosa in Europe. So far, sweep nets have been commonly used to monitor spittlebugs in ground vegetation and canopies of trees or shrubs. From 2018 to 2020, we conducted several field experiments to test the effectiveness of sticky traps as tool for monitoring insect populations in different crops. We evaluated different coloured sticky traps (white, red, blue, yellow, yellow with circle-pattern and yellow with line-pattern) in comparison with sweep nets, and validated their efficiency on olive, almond, and cherry orchards. Results showed that: (i) yellow traps were the most attractive for Philaenus spumarius and Neophilaenus campestris; (ii) while in olive groves no differences were recorded for the yellow traps with different background, in the almond and cherry orchards, the capture of P. spumarius on those with black line-pattern were significantly higher than the other in some of the inspection periods; (iii) leafhoppers were the predominant non-target insects captured on the yellow sticky traps in our experimental fields. Comparison between yellow sticky traps and sweep nets for monitoring P. spumarius clearly showed that early in the season (April-May), i.e. when the adults emerge, insects were prevalently caught by sweeping net. Later on, the number of adults captured on traps were constantly higher than those captured by sweep nets, especially in olive groves with medium-high population densities and in almond and cherry orchards. In conditions with low population densities of P. spumarius, the two methods showed similar efficiency. Regarding N. campestris, no differences were observed between the two sampling methods on olive trees and cherry. While on almond yellow sticky traps were mostly effective than sweep net, prevalently in late summer when leaves fall and sweep net were difficult to use due to the stiffness of the branches. Our results suggest that the use of sweep nets soon after the emergence of the adults coupled with sticky traps for the rest of the adult season, can expedite monitoring programs finalized to the implementation of control measures (i.e. defining the threshold and the best time for insecticide applications)., IT; PDF; biagiotedone2@gmail.com

Tese de mestrado em Ecologia e Gestão Ambiental, Universidade de Lisboa, Faculdade de Ciências, 2020 Submitted by Cristina Manessiez (camanessiez@fc.ul.pt) on 2020-12-18T17:59:37Z No. of bitstreams: 1 ulfc125992_tm_Ganna_Popova.pdf: 13035984 bytes, checksum: 58846cd96fd21a158692bafb9d12c26b (MD5) Made available in DSpace on 2020-12-18T17:59:47Z (GMT). No. of bitstreams: 1 ulfc125992_tm_Ganna_Popova.pdf: 13035984 bytes, checksum: 58846cd96fd21a158692bafb9d12c26b (MD5) Previous issue date: 2020

Much of the work regarding insecticidal efficacy against Philaenus spumarius has been initiated only in the past few years, when the control of this spittlebug species in the area where outbreaks of Xylella fastidiosa emerged, became essential. Among the numerous formulations (synthetic and organic insecticides) tested to control the adults on olives, a major affected European crop, neonicotinoids and pyrethoids showed the highest efficacy and persistence (Dongiovanni et al., 2018). These trials were extended in 2018 and 2019 by testing a new formulate based on acetamiprid and one based on cyantraniliprole, a systemic insecticide belonging to anthranilic diamide. For both, results showed high efficacy against P. spumarius indicating they could be adopted for controlling spittlebug populations in the framework of the application of containment measures for X. fastidiosa. Whereas, with the purpose of reducing the efficiency of X. fastidiosa vector transmission under organic farming management, applications of kaolin were tested for four consecutive years as a preventive approach to protect a new olive plantation exposed to the natural inoculum pressure. Although, applied on a calendar basis, the use of kaolin did not protect the young olives from infections and subsequent symptoms development. Surprisingly, this was also the case of the plants treated with the insecticide used as control, based on imidachloprid, for which, even if to a lower extent, infections also occurred. Attempts were also made to implement strategies, alternative to the mechanical control of weeds, for controlling the juveniles, a stage of the insect life when they are more vulnerable and control can be more efficient. Sowing different gramineous species to replace the natural ground vegetation, applications of herbicides and pyroherbicides, were compared. Soil tillage, pyroherbicides and herbicides applied in spring were the only interventions able to reduce almost to zero the presence of juvenile spittlebugs. The experimental data herein developed will be helpful for the end-users to choose better options for the management of this vector in different agroecosystems.

Most of the diseases associated to the insect-transmitted bacterium Xylella fastidiosa (Xf) have been described in North and South America, but in the last five years widespread infections were reported in a restricted area of the Apulia region (southern Italy), on olives suffering a severe disease denoted “olive quick decline syndrome - OQDS”. Following this first report, several outbreaks have been reported in Corsica and Balearic Islands, and some in mainland France and Spain. Because many xylem sap-feeding insects can function as vectors for the transmission of this exotic pathogen in EU, several research programs are ongoing to assess the role of candidate vectors in the spread of the infections. Initial investigations identified Philaenus spumarius as the predominant vector species in the olive orchards affected by the OQDS. Additional experiments carried out over the past two years included, the spittlebugs Philaenus italosignus and Neophilaenus campestris, and of the planthopper Latilica tunetana (Hemiptera Issidae). Adults have been tested in transmission experiments to assess their ability to acquire the bacterium from infected olives and to infect different susceptible plant species. Acquisition rates determined by testing individual insects in quantitative PCR assays, ranged from 4,9% in N. campestris to 22% in P. italosignus, whereas no acquisition was recorded for L. tunetana. Successful transmissions were detected in some of the plant species exposed to P. italosignus or N. campestris, whereas L. tunetana did not transmit, even when adults were collected directly from the canopies of field-infected trees a nd tested positive in qPCR (1,4%). The ecological and epidemiological relevance of these findings are discussed. Although still limited, the data so far collected on the candidate vectors of Xf in Europe remark the major, if not exclusive, role of spittlebugs in the spread of this emerging pathogen.

Tese de mestrado, Ecologia e Gestão Ambiental, Universidade de Lisboa, Faculdade de Ciências, 2017 Submitted by Teresa Boa (tdboa@fc.ul.pt) on 2018-02-28T15:44:27Z No. of bitstreams: 1 ulfc124352_tm_Ana_Carina_Neto.pdf: 11749247 bytes, checksum: 69a69c2b527b9368b947d0fe44edf97a (MD5) Made available in DSpace on 2018-02-28T15:44:36Z (GMT). No. of bitstreams: 1 ulfc124352_tm_Ana_Carina_Neto.pdf: 11749247 bytes, checksum: 69a69c2b527b9368b947d0fe44edf97a (MD5) Previous issue date: 2017

Neophilaenus campestris (Fall��n, 1805) (Figs 7, 16 a���b, 26) Cercopis campestris Fall��n, 1805: 252. Neophilaenus campestris (Fall��n, 1805): Dlabola (1981): 211. Material examined. Alborz: Azadbar, vii. 2005, vii. 1995, leg. Linnavuori, 1 ♂, 1 ♀ (NMWC). Azarbaiejan-e Sharghi: Kalibar, 1793m, 2.ix. 2007, leg. Mozaffarian, 1 ♂ (HMIM). Gilan: Barasar, vii. 1996, leg. Linnavuori, 1 ♂ (NMWC); Ganjeh, vi. 1995, leg. Linnavuori, 2 ♂, 1 ♀ (NMWC); Jirandeh, vii. 1996, leg. Linnavuori, 4 ♂, 2 ♀ (NMWC); Manjil, vii. 1995, leg. Linnavuori, 11 ♂, 11 ♀ (NMWC); Masuleh, vii. 1996, vii. 2002, leg. Linnavuori, 7 ♂, 7 ♀ (NMWC); Salansar. v. 2005, leg. Linnavuori, 4 ♂, 2 ♀ (NMWC); Sangrud, vi. 2005, viii. 2007, vi. 1996, leg. Linnavuori, 47 ♂, 55 ♀ (NMWC); Tutbabon���Rudbar, vi. 1995, leg. Linnavuori, 2 ♂, 2 ♀ (NMWC). Golestan: 35km N. Kalaleh, vii. 2005, leg. Linnavuori, 3 ♂ (NMWC); Baghshah, 930m, 1.viii. 2008, leg. Lashkari, 8 ♂, 3 ♀ (HMIM); Ghozlogh, 1686m, 30.viii. 2008, leg. Lashkari, 141 ♂, 162 ♀ and 1935m, 7.viii. 2008, leg. Lashkari, 2 ♂, 2 ♀ (HMIM); Jozvali, 630m, 30.viii. 2008, leg. Lashkari, 3 ♂, 1 ♀ (HMIM); Koylar, 1250m, 23.vii. 1996, Ebrahimi/ Nazari, 4 ♀ (HMIM); Maravehtappeh, vii. 2005, leg. Linnavuori, 3 ♂, 2 ♀ (NMWC); Tang-e Gol, 700���1000m, 27���28.vi. 2000, leg. Barari/ Mofidi/ Deuv, 1 ♂ (HMIM); Toskestan, 1450m, 30.viii. 2008, leg. Lashkari, 1 ♂, 1 ♀ and 2167m, 7.viii. 2007, leg. Lashkari, 3 ♂, 4 ♀ (HMIM). Khorasan-e Shomali: 150 km W. Bojnurd, viii. 1994, leg. Linnavuori, 2 ♂, 1 ♀ (NMWC); Zard, 100 km WNW Bojnurd, vii. 1994, leg. Linnavuori, 1 ♂ (NMWC). Mazandaran: Hassanabad, vii. 1996, leg. Linnavuori, 1 ♂ (NMWC). Distribution and habitat. The publications by Dlabola (1958, 1961, 1964, 198) and Nast (1972) and the museum specimens indicates the existence of this species from 400 m to 2545 m, in sunny habitats on Poaceae in mountains, steppes and Hyrcanian type forests habitats. Neophilaenus campestris is known as a pontomediterranean faunal element and is recorded from Europe, Northern Africa, Western Asia and Iran (North, fig. 26). The species is considered as a potential vector for the bacterium X. fastidiosa, which infests olive trees (Anonymous 2013)., Published as part of Mozaffarian, Fariba & Wilson, Michael R., 2015, The aphrophorid spittlebugs of Iran (Hemiptera: Cercopoidea: Aphrophoridae), pp. 442-456 in Zootaxa 4052 (4) on pages 447-448, DOI: 10.11646/zootaxa.4052.4.2, http://zenodo.org/record/238924, {"references":["Fallen, C. F. (1805) Forsok till Svenska Cicad-Arternas uppstallning och beskrifning (continued). Nya Handligar. Kongliga Svenska Vetenskaps-Akademiens. Uppsala and Stockholm, 26, 229 - 253.","Dlabola, J. (1981) Ergebnisse der tschechoslovakisch-iranischen entomologischen Expeditionen nach dem Iran (Mit Angaben uber einige Sammelresultate in Anatolien) (1970 und 1973) (Homoptera, Auchenorrhycha). - II Teil. Acta Musei Nationalis Pragae, 40, 127 - 311.","Dlabola, J. (1958) Zikaden - Ausbeute vom Kaukasus. Acta Entomologica Musei Nationalis Pragae, 32, 317 - 352.","Dlabola, J. (1961) Die Zikaden von Zentralasien, Dagestan und Transkaukasien (Homopt. Auchenorrhyncha). Acta Entomologica Musei Nationalis Pragae, 34 (587), 241 - 358.","Dlabola, J. (1964) Ergebnisse der Albaniens - Expedition 1961 des Dt. Ent. Inst., 22: Auchenorrhyncha. Beitraege zur Entomologie, 14, 269 - 318.","Nast, J. (1972) Palaearctic Auchenorrhyncha (Homoptera) An annotated check list. Polish Scientific Publishers, Warsaw, Poland, 550 pp."]}

The phytosanitary emergency caused by the spread of Xylella fastidiosa in the Mediterranean has raised demands for a better understanding of the ecology of its presumed and candidate insect vectors. Here, we present the results of a two-year survey carried out in olive groves across southern, eastern and Central Spain and northeastern Portugal. Several sampling methods were tested and compared to select the most appropriate to estimate population levels of potential vectors of X. fastidiosa. The spittlebugs Philaenus spumarius and Neophilaenus campestris (Hemiptera: Aphrophoridae) were the main species associated with olive groves. Both species were widely present on herbaceous ground vegetation within the olive groves; P. spumarius mainly associated with Asteraceae and N. campestris with Poaceae. Due to the patchy distribution of spittlebugs within the olive groves, sweep nets were the most effective and least time-consuming sampling method for the estimation of population size both in the ground cover and tree canopies. Trends in population density showed that spittlebugs can be abundant on ground vegetation but very rare on olive canopies. Spittlebugs disperse in late spring to non-cultivated hosts that act as natural reservoirs. In late fall, adults return to the olive groves for oviposition. However, olive trees may act as transient hosts for spittlebugs and high population densities of these insect vectors should be avoided in areas where X. fastidiosa is present.