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Im Sommer 2021 wurden parasitierte Eigelege der Grünen Reiswanze Nezara viridula (Linnaeus, 1758) in Wiener Privatgärten festgestellt. Die morphologischen und molekularbiologischen Untersuchungen ergaben, dass es sich um den Eiparasitoiden Trissolcus basalis (Wollaston, 1858) handelt. Dies ist der erste Nachweis von Trissolcus basalis aus Nezara viridula Eigelegen in Österreich., Journal für Kulturpflanzen, Bd. 74 Nr. 03-04 (2022): Zukünftige Wege des Pflanzenschutzes gegen Schadinsekten

���Candidatus Liberibacter solanacearum��� (Lso) is a phloem-limited phytopathogenic bacterium vectored by psyllids. Lso has caused major damage in Solanaceous and Apiaceous crops worldwide where the psyllid vectors use cultivated crops as their main host or food plant. Psyllids often have a limited range of plant hosts but may feed on plants closely related to their host. The diversity and availability of plant hosts surrounding crops plants can significantly influence the epidemiology of Lso because of vector feeding behaviour and migration (Cooper et al. 2016). In many regions the presence and diversity of Lso and its vectors is poorly understood, especially for weed hosts surrounding cultivated crops. The WeedVect project aimed to develop a better understanding of Lso, in terms of its crop hosts, vectors and native/weed hosts. Knowledge on potential vectors and natural reservoirs of Lso may help to anticipate or prevent outbreaks in new areas and mitigate the impact on crops in existing areas. Liberibacters have been found in several psyllid species and while some seem to be benign, others are known as the causative agents of plant diseases with significant impacts on crop production worldwide. For Lso several new plant and psyllid vectors are being described and different Lso haplotypes are being characterised. Discovery of these alternative insect vectors and plant hosts will improve our understanding of Lso interactions with plants and insects, evolution, and epidemiology and will inevitably increase knowledge on new haplotypes of Lso, thus broadening current knowledge on the bacterium taxonomy. WeedVect is a consortium of 3 institutions working to better understand the role of weed plants in the epidemiology of Lso. The consortium has also explored the potential role of aphids and other hemiptera as vectors of Lso. The project aimed: To improve the understanding of Lso diversity and presence in weed hosts including findings of Lso in previously unreported non-crop host plants To improve the understanding of Lso diversity, including the characterization of new Lso haplotypes, and presence of Lso in psyllids, To identify Lso within non-psyllid plant-sucking insects, including the characterization of new Lso haplotypes To assess the potential for using DNA barcoding to identify food plants of psyllids and other plant-sucking insects, Report of the Euphresco project 2017-C-257 'Role of weed hosts as pathogen reservoirs of insect vectored diseases (WEEDVECT)'

Background: The Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae), is an important pest species of African origin and has been introduced at various locations outside the species’ natural range. It has made its way into Europe in the 19th century and became well established throughout the Mediterranean Basin. It is rapidly expanding its range and has the ability to colonize a wide variety of environments. Incursions of C. capitata beyond the northern margin of its range are increasing while established populations are pushing the boundaries of the species’ current distribution further north. However, knowledge on annual and seasonal population dynamics of C. capitata is lacking. For this reason, we assessed whether populations within the core of European C. capitata distribution and populations at the edge of the distribution (marginal areas and satellite occurrences) show different genetic signatures in terms of genetic structuring and genetic diversity on a temporal scale. Methods: To address our objectives, flies were repeatedly collected at locations in core, marginal and satellite regions within the C. capitata distribution. DNA samples were acquired and submitted for Whole-Genome Resequencing, followed by SNP- calling. Genetic differentiation (FST) was calculated and spatio-temporal structuring was assessed using admixture, principal component and cluster analysis together with kinship estimation. In order to test for significant differences between seasons, a series of permutation tests were performed. Results: C. capitata in Europe exhibits a low level of spatial genetic structuring and could be a typical example of range expansion with a rapid invasion of suitable habitat. Additionally, we bring forward evidence of significant annual variation in genetic composition in populations of C. capitata at multiple locations. The case study of satellite occurrences (Vienna, Austria) suggested that isolated allotments where fruits and vegetables are grown on a small scale, likely serves as a habitat of transient nature with independent year- to-year genetic variation. Conclusion: Here, we provide evidence for annual variation in genetic composition at both the core and margin of the distribution of C. capitata. The occurrence of C. capitata in Vienna is likely associated with annual fruit import and populations there are assumed to be transient. Geographical structuring of C. capitata in Europe is weak which is likely the result of intense gene flow and a shared ancestry.

Cryphonectria parasitica is a devastating plant pathogen infecting chestnuts (Castanea spp.). The long-distance spread of C. parasitica is thought to occur through the movement of infected plants for planting, bark or wood material. There is evidence of a long latent period on infected plants. Long latent periods are problematic as affected trees do not show symptoms for some time and are being shipped to previously non-affected areas. Plants for planting were emphasized as the highest risk pathway for entry of the pathogen into protected zones, therefore a robust, sensitive detection method to screen for latent infections of planting material is required to support plant health inspection and potential certification regimes. This project was the result of a collaboration between specialists of Cryphonectria parasitica disease in Castanea spp. The CPARA project aimed to support the diagnosis of C. parasitica in plants for planting, with a focus on latent infections. The project contributed to: - Development of a diagnostic protocol for the detection of C. parasitica in planting material. This included development of an extraction protocol, and comparison of published real-time PCR tests. - Validation of the published real-time PCR test by Chandelier et al., (2019) for use on planting material to detect early infections before symptom expression., Report of the Euphresco project 2017-A-249 'Early detection of Cryphonectria parasitica in planting material (CPARA)'

Additional file 3: Figure S2. Approximate location and CRR1 genotype of E. amylovora isolates in the region spanning from Eastern Europe to Central Asia. Two main areas of influence are recognizable, with the A-derived genotype radiating from the region surrounding Black and Caspian Seas and the D-derived genotype moving toward Russia from Eastern Europe. It can be noted that in Russia, the region between the rivers Don and Volga apparently lies at the crossroad between the movements of the two above-mentioned primal populations.

Additional file 4: Figure S3 (a–k). Prevalence of A-derived (blue), D-derived (green) and PCR null genotype in Austria in the period 1993–2017. The number of isolates retrieved in each federal state in a certain timeframe is indicated in parentheses using the pattern (A-D-null). Federal states are colored accordingly. The interval for each slide is highlighted on the timeline, which shows the cumulative data for the whole country.

Additional file 1: Figure S1. a Schematic structure of CRR1 and CRR2 in E. amylovora. The CRR is constituted of an AT-rich leader sequence followed by identical direct repeats (DR) that are separated by unique spacers (S1–S8). The sequence of the DR is highly similar between CRR1 and CRR2 and differs only in two adjacent base pair in the central region of the 29-bp sequence (Rezzonico et al. 2011). Newest spacers are incorporated immediately downstream of the AT-rich leader sequence. b Spacer arrangement and evolution of a CRISPR array in six hypothetical strains (A-F) sharing a common ancestor. Older spacers are shared among the different strains and are located at the 3’ end of the array. New spacers are added in a polar fashion at the 5’ end next to the leader (L) sequence. Spacers of the same color sharing the same vertical position are identical between strains. Divergence points, i.e. the addition of different set of spacers in two lineages, are represented by the change in their color. In the depicted example, B is probably the most ancient strain, since it is the one which is closest to the last common ancestor (situated on the branching point between A-C and D-F). Strain A is more recent than B as suggested by the presence of seven additional spacers at the 5’ end of the array. It is also clear that strain C diverged from the lineage containing A and B before their separation into two distinct strains. On the right side of the tree the loss/duplication of two internal spacers in strain F, although close to the 3’ end of the array, suggests that the latter strain has separated from strain E only after the branching point between D and E (otherwise the same deletion would have been present also in strain D).

Xylella fastidiosa is a bacterial pathogen transmitted by insect vectors. In the Americas, the primary vectors are Cicadellidae, subfamily Cicadellinae, i.e. glassy-winged and blue-green sharpshooters whereas in Europe the common meadow spittlebug or froghopper Philaenus spumarius has been identified as the primary vector beside two other spittlebugs, Neophilaenus campestris and Philaenus italosignus. P. spumarius is abundant in Europe, wide-ranging geographically and present in a variety of habitats as well as being highly polyphagous. However, it is important to recognise that although Philaenus spumarius is the most important vector identified at this time, any xylem feeding insect could potentially act as a vector. Although routine surveillance for X. fastidiosa is carried out on plant material it is also possible to detect the bacterium within the foregut of insects. Recent studies have indicated that, in conjunction with plant surveys, testing vectors for Xylella could be an important tool for monitoring for the bacteria within the wider environment. The main activities of this project focussed on: Surveys of potential vector species and association with plant hosts within different habitats including agroecosystems such as vineyards and olive groves collecting data on abundance and host plant preferences. Evaluation of sampling and trapping methods for vectors surveillance. Sweep netting is the most effective method and is therefore recommended. However yellow sticky-traps or pan-traps as passive trapping methods also proved to be suitable for monitoring for the presence of spittlebugs. Development and evaluation of molecular tests to identify vectors alongside well-established DNA barcoding techniques. CO1 sequences are readily available within GenBank and BOLD for several Philaenus and other species. A specific real-time PCR test was developed for the identification of Philaenus spumarius. Development and evaluation of molecular methods (PCR, Real-time PCR and LAMP) for the detection of X. fastidiosa in vectors. CTAB is the most suitable extraction method for the obtention of high concentration of X. fastidiosa genomic DNA from insects. Initial results indicate that although real-time PCR is more sensitive than LAMP, the LAMP test provides advantages as a useful tool for screening vectors in the field. A CTAB extraction protocol is the most suitable for the obtention of high concentration of Xf-genomic DNA from insects. Comparative analysis was also undertaken between different molecular techniques (PCR, Real-time PCR and LAMP). Initial results indicate that although qPCR is more sensitive than LAMP that the LAMP assay is a useful tool for screening vectors., Report of the Euphresco project 2016-F-221 'Xylella fastidiosa and its insect vectors'

PhyLib II is a consortium of 18 institutions from 14 countries that continued the work of the PhyLib consortium. The consortium collaborated on the project: ‘The biology and epidemiology of ‘Candidatus Liberibacter solanacearum’ (Lso) and potato phytoplasmas and their contribution to risk management in potato and other crops (PhyLib II)’. The aims of this project were to expand knowledge of emerging bacterial plant diseases associated with the presence of phytoplasmas and Lso and to survey their distribution, genetic diversity, epidemiology, insect vectors, and risk to crops worldwide. The consortium aimed to co-ordinate research on these crop pests and to provide a network of expertise to develop detection methods and a framework within which to share knowledge and compare the experiences of disease epidemiology across a wide range of geographical locations including North America (Canada), Northern Europe, the Mediterranean basin, Central Europe and Eastern Europe. The consortium developed and validated methods for the extraction of metagenomic DNA and total RNA and for the detection of bacterial DNA from complex matrices including plants, seeds and insect vectors. This involved testing current methodologies and developing novel approaches including High Throughput Sequencing (HTS)-based diagnostic techniques. Through field surveys carried out by the partners, our knowledge of the distribution and genetic diversity of phytoplasmas and Lso worldwide has improved. This includes the discovery of novel Lso haplotypes in different plants and insect vectors and the finding of Lso and phytoplasmas in areas where hitherto they were not known to be present. The consortium was effective in promoting exchange of materials between partners and sharing knowledge, enabling countries to facilitate testing for phytoplasmas and Lso. The consortium will build on the success of PhyLib II and the Euphresco project PhyLib III (17 institutes from 14 countries) has started in 2020., Report of the Euphresco project 2015-B-115 'The biology and epidemiology of 'Candidatus Liberibacter solanacearum' and potato phytoplasmas and their contribution to risk management in potato and other crops (PhyLib II)'

Slide of the Euphresco project 2017-A-242 'Early detection of fungal storage pathogens on pome fruits (EARLDETEC)', Project funded through the Euphresco network

The PROMODE project workplan was developed to achieve two goals: (i) to strengthten/build the capacity of the laboratories working on the diagnosis of plant pathogens and (ii) to improve the performance (such as reliability and sensitivity) of the diagnostic tests used for the detection and identification of X. fastidiosa in host plants and insect vectors. In order to avoid duplication of efforts, the PROMODE network had set relevant collaborations with the EU-funded consortia of POnTE (GA 635646) and XF-ACTORS (GA 727987), whose research activities were also focused on the same pathogen. Three main actions were undertaken during the PROMODE project lifespan: To support the organization of laboratory training courses through which trainees could get hands-on practise on different diagnostic protocols; To organize proficiency tests and test performance studies, to gather data on the proficiency of the laboratories involved in the official monitoring program as well as to assess the performance criteria of the different diagnostic tests available. To improve specific aspects of the diagnostic protocols: i.e. use of novel approaches like digital PCR, LAMP or HTS, and to validate the use of reliable internal controls. Four distinct training courses were organized and three large interlaboratory validations were carried out. Useful information on the most suitable diagnostic tests for the rapid detection of the bacterium in different plant matrices was obtained, as well as data on the detection limit of the different tests. The test performance studies carried out within PROMODE implemented the availability of supporting validation data for the diagnostic tests nowadays included in the EPPO Diagnostic Protocol for X. fastidiosa (EPPO 7/24). With regard to the development of novel diagnostic tests, partners of PROMODE successfully demonstrated the possibility to detect the bacterium in the host plants by digital PCR, HTS, and triplex real-time PCR. The PROMODE network was actively involved in numerous dissemination events, among which the most relevant was the co-organization of the first European Conference on Xylella fastidiosa, held in November 2017 in Palma de Mallorca (Spain)., Report of the Euphresco project 2015-F-146 'Harmonized protocol for monitoring and detection of Xylella fastidiosa in its host plants and its vectors (PROMODE)'

Monitoring and surveillance of bacterial plant pathogens is vital in efforts to control disease and maintain freedom from alien and newly emerging diseases. Rapid and reliable identification of species and pathovars provides the primary means of evaluating the disease threat from isolated pathogens. With the development and reduced cost of DNA sequencing technologies, phylogenetic-based identification based on comparative sequence analysis of protein coding genes has been shown to be rapid, reliable, reproducible and cost-effective. Multilocus sequence typing (MLST), multilocus sequence analysis (MLSA) and DNA barcoding methods are all now commonly used procedures for identification of bacteria to genus, species and subspecific levels. These methods enable discrimination of species, strains and pathovars that could not previously be reproducibly resolved using traditional phenotype profiling methods, representing a significant advance in pathogen identification. Full taxonomic identification using MLST, MLSA or multiple barcoding markers from a series of housekeeping genes can be time consuming and expensive and is not always required for routine identification purposes in the diagnostic laboratory. This work was therefore undertaken to validate a number of protocols, each based on partial sequence analysis of a single gene previously used in more comprehensive phylogenetic analyses, for the routine identification of specific plant pathogenic bacteria of quarantine importance. The aim of the project was to collate, evaluate and format data from published phylogenetic studies and ongoing sequencing studies in European diagnostic laboratories to provide standardised protocols for routine use in diagnostic laboratories for rapid identification of bacterial plant pathogens of statutory importance (including certain Xanthomonas spp., pathovars of the Pseudomonas syringae complex, Erwinia amylovora and Dickeya spp)., Scientific report of the Euphresco funded project 'Rapid identification of quarantine bacterial plant pathogens by sequence comparisons within single housekeeping genes'

For the EU member states there is no harmonized diagnostic method for Erwinia stewartii ssp. stewartii (Pantoea stewartii ssp. stewartii). The EPPO protocol PM 7/60 (1) lists several tests for the first investigation and the following isolation/screening and identification. These tests haven’t been tested in ring tests so far. For the preliminary examination, isolation, IF, ELISA and conventional PCR were proposed. The EPPO protocol contains no information on sensitivity, specificity and reproducibility. In addition, naturally infested seeds were not used for the development of these protocols. Newly available methods as real-time assays were also considered for inclusion in the ring test. The research aims of the project were validation and standardisation of the diagnostic methods used by national plant protection services and other relevant laboratories, considering detection and identification methods by ring testing. The ring test allowed to: 1. Determine sensitivity, specificity and reproducibility of the different methods. 2. Compare different media for the isolation of the bacteria, and compare isolation with other tests, using artificially contaminated seed. 3. Test sensitivity, specificity and reproducibility of the results of methods used so far (IF and ELISA) and the PCR (with previously released primers) with naturally infected seed, or with artificially contaminated samples if naturally infected seeds., Scientific report of the Euphresco funded project 'Ring test on diagnostic methods for Erwinia stewartii ssp. stewartii (Pantoea stewartii ssp. stewartii)'

The project aimed to provide new knowledge of the epidemiology and diagnosis of Potato spindle tuber viroid (PSTVd), Citrus exocortis viroid (CEVd), Columnea latent viroid (CLVd), Chrysanthemum stunt viroid (CSVd), Tomato apical stunt viroid (TASVd) and Tomato chlorotic dwarf viroid (TCDVd) with major efforts targeting the risk of transmission of pospiviroids from ornamental plants to crops of tomato and potato and the development and validation of diagnostic laboratory manuals tobe presented to national and EC plant health authorities for surveillance and seedt esting purposes.To address these challenges the following activities were carried out: -Surveying for new ‘natural’ host plants of the six targeted pospiviroids and investigation of host-pospiviroid interactions -Investigation of possible transmission pathways that might spread pospiviroids from ornamental plants to crops -Development of diagnostic RT-PCR-based assays for pospiviroids and validation of them by ringtesting -Development of reliable assays for the detection of PSTVd in tomato seeds, Scientific report of the Euphresco funded project 'Detection and Epidemiology of Pospiviroids' (DEP)

Zur oekopysiologischen Charakterisierung eines montanen tropischen Regenwaldes wurden Photosyntheseaktivitaet, Blatt-Mineralstoffgehalte und Blattphaenologie ausgesuchter typischer Bergregenwaldarten untersucht. Der erste Teil der Studie beschaeftigte sich mit der potentiellen Photosynthese-Kapazitaet montaner Pflanzen und ihrer Abhaengigkeit von den Blattmineralstoffgehalten, wobei auch ein Vergleich mit Pflanzen zweier Tieflandstandorte gezogen wurde. Dabei wurde eine neue, sensiblere Methode zur Erfassung von Naehrstofflimitierungen entwickelt, die darauf abzielt aus Korrelationen der Photosynthesekapazitaeten mit den Naehrstoffverhaeltnissen den Einfluss der einzelnen Naehrstoffe zu quantifizieren. Eine Kombination dieser Aussagen mit Ergebnissen von Bodenmineralstoffanalysen sowie mit den N-Isotopen Verhaeltnissen in den Blaettern, die eine Abreicherung an “15N anzeigen, deuten stark auf eine N Limitierung des montanen Standortes hin. Nach dem in Literatur bekannten Korrelationsverfahren der Photosynthesekapazitaet mit den Gehalten der einzelnen Mineralstoffen in den Blaettern wuerden der montane und der sekundaere Tiefland-Standort durch N und P limitiert und der primaere Tieflandwald durch N und K kolimitiert sein. Einige dieser Ergebnisse widersprechen allerdings etablierten Naehrstofflimitierungsmodellen und werden deshalb mit Vorsicht diskutiert. Im zweiten Teil der Studie wurden die Photosynthesekapazitaet, der Kohlenstoffgewinn und die Blatt-Stickstoffkonzentrationen von drei tropischen Bergregenwaldbaumarten fuer die gesamte Blattlebensdauer bestimmt. Die Ergebnisse bestaetigen die Verwendbarkeit zweier Methoden zur Bestimmung des Kohlenstoffgewinnes anhand von Kurzzeitmessungen erstmalig an einem Montanstandort: So koennen einerseits Jahreskohlenstoffbilanzen aus Blattstickstoffbestimmungen und andererseits Tageskohlenstoffbilanzen durch Korrelationen mit Photosynthesekapazitaeten erhalten werden. Die Blatt-Stickstoffkonzentrationen scheinen einen Einfluss auf die Photosynthesekapazitaeten von zwei der untersuchten Baumarten zu haben. Nachdem eine moegliche N-Limitierung durch Duengung abgeschwaecht wurde, wuchs der Einfluss von Licht auf die Photosynthese von Clusia und Hedyosmum. Geduengte Pflanzen hatten hoehere N-Konzentrationen in den Blaettern, die Photosyntheseraten blieben jedoch unveraendert. Der dritte Teil der Studie beschaeftigte sich mit dem Einfluss von Klimafaktoren auf die Blattphaenologie von 6 Bergregenwaldarten. Alle Arten waren immergruen, zeigten aber dennoch saisonale Schwankungen in der Blattproduktion und im Laubabwurf. Waehrend bei Calophyllum, Lysianthus und Eugenia durch Trockenheit der Laubabwurf hervorgerufen wurde, war andererseits die Blattproduktion von Ardisia in der Trockenzeit angeregt und es bestand eine Abhaengigkeit der Blattproduktion vom Licht. Hoehere Temperaturen hatten einen positiven Einfluss auf die Blattproduktion von Calophyllum. Generell scheint die Blattphaenologie endogen gesteuert zu sein, allerdings hatten klimatische Parameter teilweise signifikante Einfluesse auf die Blattproduktion. Einige dieser Einfluesse veraenderten sich bei den geduengten Pflanzen. Dies deutet auf eine Verschiebung der Kosten-Nutzen Bilanz nachdem eine Naehrstofflimitierung durch Duengung ausgeschlossen wurde., An ecophysiological approach on a montane tropical forest on Cerro Jefe (Panama) was performed, to describe the photosynthetical characteristics, nutrient relations and leaf phenological patterns of typical plants on different time scales. The first part of the study was dedicated to the potential photosynthetical capacity of montane plants and their relation to leaf nutrient characteristics, compared with two lowland forest sites, differing in succession and water availability. A new and more precize method in detecting nutrient limitation was developed, using correlations of photosynthetic capacity with nutrient ratios and quantifying the influence of the single nutrient within such ratios. A combination of the results with soil mineral analyses and nitrogen isotope ratios, indicating that the montane site is depleted in “15N, give strong evidence, that plants at the studied montane site are primary nitrogen limited. Applying the from the literature already established method of the correlation significance of photosynthetic capacity with a single nutrient, photosynthesis at the montane site and the secondary lowland forest would thereafter be N and P, and the primary lowland site be N and K co-limited. Some of these results are contradictory to general models of nutrient limitation in the tropics and are therefore discussed carefully. A second part of the study was dedicated to the photosynthetic capacity, carbon gain and leaf N concentrations of three tropical montane tree species on an ontogenetic basis. The results obtained, confirmed two methods of predicting carbon gain of plants, with much less time consuming measurements, for the first time for tropical montane plant species. Annual carbon gain can be predicted from mean leaf N concentration although on montane forest trees at a natural stand, and daily carbon assimilation can be predicted with short-term measurements of photosynthetic capacity. There is evidence that leaf N has an influence on photosynthetic parameters at least for two analysed tree species. Light was related to photosynthetic parameters of Clusia and Hedyosmum especially after a possible N limitation was removed. However, photosynthesis was saturated at very low light levels, resulting in the highly significant correlation of photosynthetic capacity and daily carbon and the confirmed prediction method. Fertilized plants showed a luxurious accumulation of leaf N, without significant response in photosynthesis. The third aspect of the study dealt with the leaf phenology of six tree species and their dependence on climatic triggers. All studied species were evergreen, but nevertheless showed some fluctuation in leaf production and fall. Calophyllum, Lysianthus and Eugenia leaf phenology was negatively influenced by drought parameters suggesting the dry season period as a trigger for leaf fall and the rainy season for leaf production. Ardisia showed the opposite pattern concerning water related parameters, additionally there was a significant positive influence of light on the number of leaves, suggesting this parameter as a positive trigger for this species. Increasing of air and soil temperature were positive triggers for production of Calophyllum leaves and a decrease of air temperature enhanced leaf mortality of Lysianthus plants. However, potential geographical daylength was positively related to air and soil temperature and could have a masked influence on leaf phenology. Leaf phenology is suggested to be internally programmed, in addition triggered by external factors. Some climatic influences changed markedly after fertilization for the single plant species. However, a single factor that was valid for a majority of the analysed tree species could not be found. Nonetheless, a shift in leaf cost-benefit balance after fertilization can be suggested Apparently, the interrelation of these climatic parameters and the relatively weak seasonality masked a clear effect on the leaf phenology of this montane forest species.