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Biological invasions increase with the intensity of globalization, human activities, and climate change. Insects represent a high potential of invasive species due to their adaptability to new environment. We analysed here the potential of an Asian phytophagous bug, Corythauma ayyari (Heteroptera, Tingidae) to become widespread, recently recorded in Europe, and that depends on Jasminum spp., an ornamental plant widespread in Europe. We modelled its current distribution, projected it into the future and tested its niche overlap between native and invaded areas. When considering the host plants as environmental variables, the analysis shows that C. ayyari shifted to a new ecological niche but its distribution is restricted by its host plant distribution. Including or excluding the host plants as environmental variables has an impact on C. ayyari distribution. We recommend to consider host plant interactions when dealing with niche modelling of phytophagous species. [ABSTRACT FROM AUTHOR]

Butterflies are charismatic insects and have been well studied, particularly in Europe. They are disproportionately used in generating and testing hypotheses; on everything from general evolutionary processes, such as speciation or host association dynamics; to conservation‐related studies, such as climate change or habitat loss. Accurate lists of the larval foodplants for European butterflies are not readily available. Mistakes are propagated and information cannot be checked for accuracy. The level of evidence is unknown, and how usage varies between countries is poorly understood. The study consulted 1119 references to produce 19,488 records of larval foodplants for European butterflies. This resulted in 5589 larval host plant records for 464 European butterfly species, with multiple references, enabling information to be checked. Information was unavailable for 59 species. The level of evidence for each relationship shows the current state of knowledge. Significant issues were identified for 3.9% of records extracted from references due to mistakes, ambiguous or unknown plant names, distribution issues, resulting in information being lost. Plants with questionable distributions suggest either mis‐identification or species that have been split. Little is known about plant usage in Eastern Europe. The larval foodplants of many monophagous and Satyrinae butterflies are poorly studied. Only 63% of threatened 2010 Red Listed butterflies have reliable host plant records. The study has provided ecologists with a valuable resource, of a more accurate checklist of the larval foodplants for each European country. Why plant usage varies over a butterfly's distribution opens up some interesting research questions. [ABSTRACT FROM AUTHOR]

Wheat dwarf disease (WDD) is an important disease of monocotyledonous species, including economically important cereals. The causative pathogen, wheat dwarf virus (WDV), is persistently transmitted mainly by the leafhopper Psammotettix alienus and can lead to high yield losses. Due to climate change, the periods of vector activity increased, and the vectors have spread to new habitats, leading to an increased importance of WDV in large parts of Europe. In the light of integrated pest management, cultivation practices and the use of resistant/tolerant host plants are currently the only effective methods to control WDV. However, knowledge of the pathosystem and epidemiology of WDD is limited, and the few known sources of genetic tolerance indicate that further research is needed. Considering the economic importance of WDD and its likely increasing relevance in the coming decades, this study provides a comprehensive compilation of knowledge on the most important aspects with information on the causal virus, its vector, symptoms, host range, and control strategies. In addition, the current status of genetic and breeding efforts to control and manage this disease in wheat will be discussed, as this is crucial to effectively manage the disease under changing environmental conditions and minimize impending yield losses. [ABSTRACT FROM AUTHOR]

In this paper, a comprehensive overview of the 'Candidatus Liberibacter solanacearum' presence in Europe was provided. The analyzed findings revealed that, since the first appearance of this pathogen in Finland and Spain in 2008, it has spread to 13 new European countries. Therefore, 'Ca. L. solanacearum' has spread very quickly across the European continent, as evident from the emergence of new host plants within the Apiaceae, Urticaceae, and Polygonaceae families, as well as new haplotypes of this pathogen. Thus far, 5 of the 15 'Ca. L. solanacearum' haplotypes determined across the globe have been confirmed in Europe (haplotypes C, D, E, U, and H). Fully competent 'Ca. L. solanacearum' vectors include Bactericera cockerelli, Trioza apicalis, and B. trigonica; however, only T. apicalis and B. trigonica are presently established in Europe and are very important for plants from the Apiaceae family in particular. Moreover, psyllid species such as B. tremblayi, T. urticae, and T. anthrisci have also been confirmed positive for 'Ca. L. solanacearum'. Constant monitoring of its spread in the field (in both symptomatic and asymptomatic plants), use of sensitive molecular diagnostic techniques, and application of timely management strategies are, therefore, of utmost importance for the control of this destructive pathogen. [ABSTRACT FROM AUTHOR]

It has been suggested that palms of the genus Arenga (Arecales: Arecaceae) or forms close to it were distributed in the Eocene of North America and Europe. Records of Metrioxenini (Belidae), which are monophages on these palms, confirm this assumption. A new species, Succinometrioxena andrushchenkoi Legalov, sp. n. from Baltic amber is described. The new species differs from S. poinari Legalov, 2012 in the smaller body sizes, elytral punctation larger than the distances between them, and a rostrum weakly curved in females. It is distinguished from S. bachofeni Legalov, 2013 and S. attenuata Legalov et Poinar, 2020 by the forehead lacking horn-like tubercles on either side of the eyes. A description of male of S. poinari was herein compiled for the first time. A list and key to fossil Metrioxenini were given. The modern and fossil distribution of the tribe Metrioxenini and Arenga palms was shown. [ABSTRACT FROM AUTHOR]

Early detection of insect infestation is a key to the adoption of control measures appropriated to each local condition. The use of remote sensing was recommended for a quick scanning of large areas, although it does not work well with signals bearing low intensity or items that are difficult to detect. Unmanned Aerial Vehicle (UAV, or drone) may help in getting closer to individual trees and detect atypical signals of small dimensions. The larvae of the pine processionary moth (PPM, Thaumetopoea pityocampa (Denis & Schiffermüller, 1775, Lepidoptera, Notodontidae) build conspicuous silk nests on the external parts of the host plants at the beginning of the winter and their early detection may prompt managers to adopt management techniques. This work aims at testing two deep learning methods (Region-based Convolutional Neural Network - R-CNN and You Only Look Once - YOLO) to detect the nests under three different conditions of host plant species and forest stands in southern Europe. YOLO algorithm provided better results and it allowed us to achieve F1-scores as high as 0.826 and 0.696 for the detection of presence / absence and the individual nests, respectively. The detection of all the nests that can be present on a tree is not achievable with either UAV scanning or traditional ground observation, therefore the integration of the methods may allow the complete efficiency of the surveillance. The use of UAV combined with Artificial Intelligence (AI) image analysis is recommended for further use in forest and urban settings for the detection of the PPM nests. The recommended methods can be extended to other pest systems, especially when specific symptoms can be associated with an insect pest species. [ABSTRACT FROM AUTHOR]

Leafmining insects have extraordinarily intimate relationships with their host plants and are therefore prime candidates for potential ecological speciation in sympatry, but how commonly this mode of speciation occurs in any group of life remains debated. Prior research on the pygmy moth (Nepticulidae) genus Ectoedemia using morphology, DNA barcoding, and multi‐marker phylogenetic approaches left two unresolved species complexes, each with each four described species. In this study, we thoroughly sampled each complex across a range of host plants and localities across Europe. We used a double digest restriction‐site associated DNA (ddRAD) sequencing approach to clarify species boundaries. In the E. rubivora complex, ddRAD data resolved all four species, contrary to morphological and COI data, which supports a potential scenario of host plant‐driven speciation where the host plant specialization provides an ecological barrier to hybridization. However, we found no indication of host race formation within the oligophagous E. atricollis (Stainton). In the E. subbimaculella complex, SNP data only partly distinguishes between the parapatric E. subbimaculella (Haworth) and E. heringi (Toll), but with some statistical overlap, suggesting incomplete lineage sorting which may represent early phases of host‐based ecological speciation, or admixture following a period of isolation. [ABSTRACT FROM AUTHOR]

Xylem‐feeding is apparently the only requirement making an insect a competent vector of the bacterium Xylella fastidiosa, an organism responsible for the devastation of the Southern Italian olive forest and nowadays considered one of the most feared threats to agriculture and landscape in Europe, including vineyards. Here, we used the direct current‐electrical penetration graph (DC‐EPG) technique to compare and describe the feeding behaviour on grapevine of four xylem‐feeding species considered candidate vectors of X. fastidiosa widespread in Europe, namely two spittlebugs (the meadow spittlebug Philaenus spumarius and the spittlebug Neophilaenus campestris) and two sharpshooter leafhoppers (the rhododendron leafhopper Graphocephala fennahi and the green leafhopper Cicadella viridis). We created a standard for the analysis of EPG waveforms recorded with a DC‐EPG device, describing feeding activities performed by these insects from stylet insertion into the plant to withdrawal. This standard, along with freely available software, has been developed to harmonize the calculation of feeding behavioural parameters in xylem‐feeders. The most relevant differences between the two vector taxa were the probing frequency and the dynamics of xylem ingestion. Sharpshooters tended to perform significantly more probes than spittlebugs. In contrast, the latter spent longer times in low‐frequency xylem ingestion, characterized by scattered contractions of the cibarial dilator muscle interspersed with periods of pump inactivity. Cicadella viridis was the species displaying the highest frequency of the electrical pattern found to be associated with X. fastidiosa inoculation in spittlebugs (Xe). Feeding behavioural data presented here represent an important step forward for deepening our knowledge of xylem‐sap feeding insects' interaction with both the host plants and the bacterium they transmit. [ABSTRACT FROM AUTHOR]

Wild boar is among the most abundant ungulates in Europe and its spread is locally creating concerns as a major threat to biodiversity. However, through their rooting activity, wild boars could play an effective role in the creation of specific microhabitat resources for plants and animals. Here, we tested the hypothesis that wild boar affects the habitat suitability to threatened butterflies, by evaluating the influence of rooting on multiple key aspects of the biology and ecology of the Mediterranean endemic Zerynthia cassandra. Namely, we used Z. cassandra as a model to test the effects of wild boar rooting on adult foraging opportunities, host plant occurrence, and oviposition site selection. We found that herbaceous communities disturbed by wild boar rooting have a higher proportion of plants representing nectar resources for early-flying butterflies. We also discovered that wild boar rooting positively influences the occurrence and abundance of the larval host plant of Z. cassandra, as well as the butterfly site selection for egg-laying. Our results indicate that wild boars may locally prove beneficial to endangered butterflies by favoring habitat quality and availability, and their role as ecosystem engineers should thus be further investigated to improve species and habitat management and conservation actions. [ABSTRACT FROM AUTHOR]

Modeling the potential spread of Xylella fastidiosa can document contingency plans in northern Europe, so far uncolonized by the bacterium. Through mark–release–recapture (MRR) and flight-mill experiments, the flight capacity of two potential vectors for temperate Europe was studied: Philaenus spumarius, the reported southern European vector, and Aphrophora salicina, a xylem-specialist feeding on potential host plants of X. fastidiosa. Aphrophora salicina displayed significantly better flight performances than P. spumarius. In flight-mills, the average distance flown was, respectively, 623 m vs. 102 m and the maximal distance flown was 6.16 km vs. 1.54 km in 2.5 h. In MRRs, A. salicina travelled more than 30 m in a single flight, with a maximal interception distance of 80 m after two days, highlighting that dispersal is driven by connectivity and host plant quality. Philaenus spumarius mainly jumped, with 1 m movements in length and a maximal interception distance of 32 m in 27 days. Models estimated P. spumarius' daily mean dispersal at 1.5 m and A. salicina's at 3.5 m. Although only a small part of the population moves over very long distances, this pool of efficient insects could already be sufficient to effectively spread an epidemic. As Salicaceae have been reported as host plants of the bacterium, the association of Aphrophoridae and Salicaceae in riparian areas could create bacterium reservoirs in corridors allowing for transportation over medium to long distances. [ABSTRACT FROM AUTHOR]

Sap sucking heteropteran cereal bugs—members of the Eurygaster and Aelia genus—are serious pests of wheat. Moreover, they feed on a variety of gramineous plant species, including rye, barley, oat, maize, and millet. They are widely distributed in the European continent. The purpose of this review paper is two-fold; it summarizes the currently available data on the biological characteristics, the inflicted damage, and their European distribution and, in addition, we aimed to determine their economic importance, based on data available in the current literature. For the most important cereal bug species, we have collected data on their occurrence in Europe to provide a comprehensive picture of their distribution, and characterized them according to their temperature requirements at different life stages. We have also determined the degree of their attachment to wheat as their host plant, examining the synchronization between the pests and the life cycle of the plant. Finally, we compared their migration characteristics. All the above-mentioned characteristics were merged, in order to assess and rank the damage potential of each species. [ABSTRACT FROM AUTHOR]

The sharpshooter Cicadella viridis L. (Hemiptera: Cicadellidae) is the most common sharpshooter in Europe and, given its xylem feeding behavior, is considered a potential vector of the plant pathogenic bacterium Xylella fastidiosa Wells et al. (Xanthomonadales: Xanthomonadaceae). We tested X. fastidiosa subsp. pauca ST53 (Xfp) transmission capabilities of C. viridis adults, namely 1) acquisition efficiency from four host plant species—periwinkle, milkwort, lavender, alfalfa—and from two artificial diets (PD3 and Xfm), 2) inoculation efficiency to periwinkle at different times post acquisition from different plant and artificial diet sources. The main European vector species—Philaenus spumarius L. (Hemiptera: Aphrophoridae)—was used as a control. C. viridis was able to acquire Xfp from periwinkle, milkwort, and lavender, although with low efficiency (3–16%) and from artificial diets (23–25%). Successful inoculation on periwinkle was extremely rare, being observed only three times, following feeding on milkwort plant and PD3 artificial diet sources. Our study shows that C. viridis is not a relevant vector of Xfp, given the very low transmission rate in controlled conditions, and the inability to feed on olive. The low efficiency reported here correlates with ecological constraints of the vector (mainly monocots host plants, humid environments) that make it difficult to forecast a relevant role in dispersing X. fastidiosa, at least within the present distribution of the exotic bacterium in Europe. However, a possible role of this species in spreading Xf in other agroecosystems, e.g., vineyard and stone fruits grown in humid areas, cannot be excluded. [ABSTRACT FROM AUTHOR]

Xylella fastidiosa infects several economically important crops in the Americas, and it also recently emerged in Europe. Here, using a set of Xylella genomes reflective of the genus-wide diversity, we performed a pan-genome analysis based on both core and accessory genes for two purposes: (i) to test associations between genetic divergence and plant host species and (ii) to identify positively selected genes that are potentially involved in arms-race dynamics. For the former, tests yielded significant evidence for the specialization of X. fastidiosa to plant host species. This observation contributes to a growing literature suggesting that the phylogenetic history of X. fastidiosa lineages affects the host range. For the latter, our analyses uncovered evidence of positive selection across codons for 5.3% (67 of 1,257) of the core genes and 5.4% (201 of 3,691) of the accessory genes. These genes are candidates to encode interacting factors with plant and insect hosts. Most of these genes had unknown functions, but we did identify some tractable candidates, including nagZ_2, which encodes a beta-glucosidase that is important for Neisseria gonorrhoeae biofilm formation; cya, which modulates gene expression in pathogenic bacteria, and barA, a membrane associated histidine kinase that has roles in cell division, metabolism, and pili formation. [ABSTRACT FROM AUTHOR]

In Europe, 50%–70% of former natural grassland area has been destroyed during the past 30 years due to land use changes, losses are expected to increase in the future. Restoration is thought to reverse this situation by creating suitable abiotic conditions. In this paper, we investigate the effects of sod translocation with specific vegetation to facilitate the restoration of a former intensive agricultural field into a wet meadow. First, starting conditions were optimized including modification of the local hydrology, removal of the fertilized topsoil, application of liming, and translocation of fresh clippings as a seed source. The second part aimed at restoring the habitat for the butterfly species Phengaris (Maculinea) teleius, one of the species that was especially affected by the loss of wet meadows. This species engages in a complex myrmecophilous relationship with one host plant, Sanguisorba officinalis, and one obligate host ant, Myrmica scabrinodis. We used sod translocation to create islands of habitat to promote host plant and host ant colonization. After 4 years following the restoration, we observed that plants spread from the transplanted sods to the surroundings. The vegetation composition and structure of the transplanted sods attracted colonization of Myrmica ants into the restored areas. Following the increase in vegetation cover and height, Myrmica ant colonies further spread into the restored areas. Therefore, sod translocations can be considered an effective restoration method following topsoil removal in the process of restoring wet meadows to provide a starting point for ant colonization and plant dispersion. With these findings, this paper contributes to the evidence‐based restoration of wet meadows on former agricultural fields, including complex interactions between invertebrates and their required ecological relationships. [ABSTRACT FROM AUTHOR]

The leafminers on gymnosperms receive much less attention than those on either angiosperms or ferns. Given the distinctly different leaf shape and leaf venation found in gymnosperms, they would be expected to host significantly different leafminer groups. Very few comprehensive reports on gymnosperm-feeding leafminers have been presented. Based on the well-studied fauna in North America and Europe, we compiled a list of 133 species, 30 genera and 13 families of gymnosperm-feeding leafminers. The gymnospermmining families (in descending order of leafminer number) included Tortricidae, Gelechiidae, Argyresthiidae, Yponomeutidae, Batrachedridae, Pyralidae, Adelidae, Agromyzidae, Blastobasidae, Bucculatricidae, Coleophoridae, Curculionidae and Noctuidae. There were 109 species, 22 genera and ten families in North America and 34 species, 19 genera and nine families in Europe. We compiled a list of 102 species and 16 genera of host plants, belonging to four families: Pinaceae, Cupressaceae, Taxaceae and Zamiaceae. There were 84 host species, 15 genera and three host families in North America and 46 host species, ten genera and three host families in Europe. Dominant gymnosperm-mining families and dominant host families were generally the same in the two continents. [ABSTRACT FROM AUTHOR]

The Marsh Fritillary (Euphydryas aurinia) was once widespread in large parts of Central Europe. However, in the course of the last century, populations of the butterfly largely collapsed. Here, we surveyed patch and microhabitat occupancy and its drivers in one of the last vital populations in calcareous grasslands. Our study revealed that environmental conditions at the landscape and habitat level determined the occurrence of E. aurinia in a montane agricultural landscape with low land‐use intensity. Patch occupancy increased with the cover of Devil's‐bit Scabious (Succisa pratensis) grasslands in the surroundings of the patches, habitat heterogeneity and host‐plant cover. Microhabitat occupancy was driven by a warm microclimate and high availability of host plants. In the well‐connected landscape of nutrient‐poor grasslands, patch occupancy of E. aurinia was driven by parameters defining a high habitat quality. Habitat heterogeneity very likely buffers E. aurinia populations against environmental stochasticity and, hence, enhances long‐term viability. For the gregariously feeding caterpillars of E. aurinia, host‐plant biomass is essential. Due to their more luxuriant growth, S. pratensis plants were clearly preferred, although the Glossy Scabious (Scabiosa lucida) was also widespread. Additionally, the growth of large Succisa plants was favored by soil humidity and grassland abandonment. To cope with the adverse macro‐ and mesoclimatic conditions of the study area, females of the butterfly selected host plants growing in extraordinarily warm microhabitats for oviposition. To secure long‐term viability of E. aurinia populations, we recommend creating mosaics of traditionally managed grasslands and early stages of abandonment within the patches. [ABSTRACT FROM AUTHOR]

Aim: Latitudinal clines in dietary specialization and range size are used to explain biodiversity distributions at large spatial scales, such as the latitudinal diversity gradient. The aim of this study was to test whether dietary breadth (as a dimension of niche breadth) and range size decrease towards lower latitudes in a species‐rich clade of herbivorous insects as predicted by the latitude–niche breadth hypothesis and Rapoport's rule, respectively. We also aimed to study whether these species characteristics are positively linked with each other as stated by the niche breadth–range size hypothesis. Location: Europe (35–71° N). Time period: Present‐day. Major taxa: Geometrid moths (Lepidoptera: Geometridae). Methods: For every species, we compiled information on latitudinal distribution and host‐plant use based on available literature and online sources. We estimated the level of fundamental dietary specialization of each species while accounting for phylogenetic relationships among the host plants used. We also reconstructed a phylogeny including all studied moth taxa, in order to control for phylogenetic dependence in species characteristics. Phylogenetic least squares (PGLS) analyses were used to test each of our hypotheses. Results: We analysed 631 species of geometrids (85.2% of taxa within the biogeographical region) and found strong support for the latitude–niche breadth hypothesis and for Rapoport's rule. Fundamental dietary breadth was also found to be positively related to latitudinal range size, which supports the niche breadth–range size hypothesis. These results were retained when the subfamilies Ennominae and Larentiinae were analysed separately. Main conclusions: Our findings indicate that latitudinal clines in range size and fundamental dietary breadth covary in European geometrid moths and are likely to be drivers of increased species richness towards lower latitudes. This supports the idea that both characteristics should be studied simultaneously in order to unveil mechanisms structuring biodiversity patterns at the macroecological scale. [ABSTRACT FROM AUTHOR]

The wide host range phytopathogen D. dianthicola, first described in ornamentals in the 1950s, rapidly became a threat for potato production in Europe and, more recently, worldwide. Previous genomic analyses, mainly of strains isolated from potato, revealed little sequence diversity. To further analyse D. dianthicola genomic diversity, we used a larger genome panel of 41 isolates encompassing more strains isolated from potato over a wide time scale and more strains isolated from other hosts. The phylogenetic and pan-genomic trees revealed a large cluster of highly related genomes but also the divergence of two more distant strains, IPO 256 and 67.19, isolated from potato and impatiens, respectively, and the clustering of the three strains isolated from Kalanchoe with one more distinct potato strain. An SNP-based minimal spanning tree highlighted both diverse clusters of (nearly) clonal strains and several strains scattered in the MST, irrespective of country or date of isolation, that differ by several thousand SNPs. This study reveals a higher diversity in D. dianthicola than previously described. It indicates the clonal spread of this pathogen over long distances, as suspected from worldwide seed trading, and possible multiple introductions of D. dianthicola from alternative sources of contaminations. [ABSTRACT FROM AUTHOR]

Xylella fastidiosa causes diseases in many plant species. Originally confined to the Americas, infecting mainly grapevine, citrus, and coffee, X. fastidiosa has spread to several plant species in Europe causing devastating diseases. Many pathogenicity and virulence factors have been identified, which enable the various X. fastidiosa strains to successfully colonize the xylem tissue and cause disease in specific plant hosts, but the mechanisms by which this happens have not been fully elucidated. Here we present thorough comparative analyses of 94 whole-genome sequences of X. fastidiosa strains from diverse plant hosts and geographic regions. Core-genome phylogeny revealed clades with members sharing mostly a geographic region rather than a host plant of origin. Phylogenetic trees for 1605 orthologous CDSs were explored for potential candidates related to host specificity using a score of mapping metrics. However, no candidate host-specificity determinants were strongly supported using this approach. We also show that X. fastidiosa accessory genome is represented by an abundant and heterogeneous mobilome, including a diversity of prophage regions. Our findings provide a better understanding of the diversity of phylogenetically close genomes and expand the knowledge of X. fastidiosa mobile genetic elements and immunity systems. [ABSTRACT FROM AUTHOR]

Simple Summary: Cacyreus marshalli is strictly dependent on its host plant (Pelargonium spp.), which is widely cultivated as an ornamental plant in mountain areas. An experiment demonstrated that the butterfly is able to develop on some wild geraniums, too, making mountain areas highly at risk for a potential expansion to natural habitats. We therefore decided to carry out research in a protected mountain area (Gran Paradiso National Park), focusing on the drivers which determine the distribution of C. marshalli using data provided by either an opportunistic approach or a rigorous survey protocol. The data collected via the planned survey were more informative than the opportunistic observations, which were few and narrow. We suggest investing more in citizen science projects and combining them with a designed protocol according to an integrated approach. We observed that C. marshalli distribution is strictly linked to host plant availability but is constrained by cold temperatures, although Pelargonium spp. are abundant. The temperature increase scenario showed an increase of butterfly abundance, but halving of the host plant population could drive the rate of infestation to return to what it was previously, excluding a countertrend in some high-altitude sites. It is therefore important to test management actions designed to control alien species before implementing them. Cacyreus marshalli is the only alien butterfly in Europe. It has recently spread in the Gran Paradiso National Park (GPNP), where it could potentially compete with native geranium-consuming butterflies. Our study aimed to (1) assess the main drivers of its distribution, (2) evaluate the potential species distribution in GPNP and (3) predict different scenarios to understand the impact of climate warming and the effect of possible mitigations. Considering different sampling designs (opportunistic and standardised) and different statistical approaches (MaxEnt and N-mixture models), we built up models predicting habitat suitability and egg abundance for the alien species, testing covariates as bioclimatic variables, food plant (Pelargonium spp.) distribution and land cover. A standardised approach resulted in more informative data collection due to the survey design adopted. Opportunistic data could be potentially informative but a major investment in citizen science projects would be needed. Both approaches showed that C. marshalli is associated with its host plant distribution and therefore confined in urban areas. Its expansion is controlled by cold temperatures which, even if the host plant is abundant, constrain the number of eggs. Rising temperatures could lead to an increase in the number of eggs laid, but the halving of Pelargonium spp. populations would mostly mitigate the trend, with a slight countertrend at high elevations. [ABSTRACT FROM AUTHOR]

Although much research has been carried out to develop taxa resistant to Dutch elm disease (DED), newly occurring pests represent a new challenge for the protection of elms (Ulmacae). The invasive zigzag elm sawfly (Aproceros leucopoda) is a recent invader of Asian origin in Europe defoliating elm trees that are otherwise often characterized with major resistance to DED. The range expansion of this pest poses a major threat to elms. The aim of this study was to identify the susceptibility of Ulmus crassifolia, Hemiptelea davidii and Zelkova serrata to this pest by using three different methods (oviposition trials with cut shoots and with plants in pots, and larval feeding trials with plants in pots) to define the performance of A. leucopoda on potential hosts. The fact is that A. leucopoda was unable to complete its development on either of these three taxa of Ulmaceae, whereas Ulmus pumila (the reference during the trials) was again confirmed as a true host of the pest clearly indicating that the host plant range of A. leucopoda is probably limited not only to Ulmus but also within this genus. Our results may be considered in future resistance breeding programmes, pest risk assessments, and for the selection of Ulmaceae species. [ABSTRACT FROM AUTHOR]

Charcoal rot of the sunflower roots and stems is present worldwide in all the areas with arid climate where is determining major loses. The etiologic agent of this disease is the fungus Macrophomina phaseolina considered as invasive due to its great range of host plants (over 500 species) and the very high harvest loses of the cultivated crops, mostly sunflower. The present climate changes are favouring the spread of the disease in areas where it wasn't present before. The climatic simulations realised until now in Europe shows the adaptation trend of the fungus in areas from Central and Southern Europe. The survival of the pathogen Macrophomina phaseolina in soil for long time periods makes its control almost impossible. In this work it was brought to attention the state of the art of the researches regarding the symptomatology, pathogeny, epidemiology and the control of this pathogen in conjunction with the climate change. The control strategies should highlight the prevention methods and the biological ones and less attention to be addressed to the chemical ones. The fungal and bacterial agents can be in future a viable alternative for the control of the pathogen M. phaseolina. [ABSTRACT FROM AUTHOR]

The recent history of Xylella fastidiosa Wells et al. introduction in Europe illustrates how the lack of knowledge about the bacterium‐vector‐host interactions hinders the application of effective containment strategies, with the bacterial spread that currently appears relentless. Vector behavior is a key component in plant pathogen transmission; therefore, detailed knowledge of vector probing behavior on various host plants would furnish useful data for containing the bacterium. Aiming at this goal, we carried out electrical penetration graph (EPG)‐assisted probing behavior observations of the spittlebug, Neophilaenus campestris (Fallen) (Hemiptera: Aphrophoridae), a candidate vector widespread in all the areas where X. fastidiosa is currently established. Spittlebug probing was first characterized on one of its preferred host plants, Bromus madritensis L. (Poaceae), over short (6 h) and long (16 h) time spans. Thereafter, we performed comparative observations of the spittlebug probing on B. madritensis, olive, and grapevine. Overall, the probing behavior of N. campestris, that is, the main characteristic waveforms, did not differ substantially from that of Philaenus spumarius (L.) (Hemiptera: Aphrophoridae); however, here we report and describe a new kind of xylem activity interruption, provisionally termed N2, not previously observed in P. spumarius. Considering the time spent in xylem ingestion as a percentage of the total probing time (host‐suitability indicator used for spittlebugs), grapevine and B. madritensis are the preferred hosts for N. campestris, with olive as the least suitable among the plants tested. Successful probes, that is, probes during which xylem ingestion occurred, on grapevine were 2.5× greater than olive. Therefore, our data on N. campestris probing behavior suggest that the spittlebug role in X. fastidiosa epidemiology in European vineyards should be given more attention. In the present manuscript, we also discuss the current difficulties in interpreting and analyzing the outcomes of EPG studies on spittlebugs. [ABSTRACT FROM AUTHOR]

Alien and invasive thrips (Thysanoptera) species from tropical and subtropical regions are spread into temperate countries by human activities and by shifting their natural range as a result of global climate change. The presence of glasshouses with suitable host plants may contribute to the survival of these species and provide overwintering sites necessary for establishment of outdoor populations. Sampling the first male of Microcephalothrips abdominalis in Slovakia has given the reason to discuss on climate change induced infiltration of this alien species in Central Europe and consider its possible reproduction mechanisms as well as colonization strategies. [ABSTRACT FROM AUTHOR]

Invasive species have considerably increased in recent decades due to direct and indirect effects of ever‐increasing international trade rates and new climate conditions derived from global change. We need to better understand how the dynamics of early species invasions develop and how these result in impacts on the invaded ecosystems. Here we studied the distribution and severe defoliation processes of the box tree moth (Cydalimaperspectalis W.), a tree defoliator insect native to Asia and invasive in Europe since 2007, through the combination of species distribution models based on climate and landscape composition information. The results showed that the combination of data from the native and the invaded areas was the most effective methodology for the appropriate invasive species modeling. The species was not influenced by overall landscape factors, but only by the presence of its host plant, dispersal capacity, and climate suitability. Such climate suitability was described by low precipitation seasonality and minimum annual temperatures around 0°C, defining a continentality effect throughout the territory. We emphasize the need of studying distribution and severe defoliation processes separately because we identified that climate suitability was slightly involved in limiting species spread processes but strongly constrained ecosystem impact in terms of defoliation before the species reaches equilibrium with the new environment. New studies on habitat recovery after disturbance, ecological consequences of such impact, and community dynamics in a context of climate change are required for a better understanding of this invasive species. [ABSTRACT FROM AUTHOR]

Introduction: Due to land-use intensification at productive soils and abandonment of marginal farmland, biodiversity has dramatically declined throughout Europe. The dryad (Minois dryas) is a grassland butterfly that has strongly suffered from land-use change across Central Europe. Aims/Methods: Here, we analysed the habitat preferences of adult M. dryas and the oviposition-site preferences in common pastures located in mire ecosystems of the German pre-Alps. Results: Our study revealed that plot occupancy was equal at common pastures and control plots. However, the abundance of M. dryas was higher at common pastures, although the composition of vegetation types did not differ between the two plot types. Discussion: Open fens and transition mires traditionally managed as common pastures or litter meadows (= meadows mown in autumn to obtain bedding for livestock) were the main habitats of M. dryas in our study area. They offered (i) sufficient host plants (Carex spp.), (ii) had a high availability of nectar resources and (iii) a vegetation that was neither too sparse nor too short. In contrast, both abandonment and intensive land use had negative impacts on the occurrence of the endangered butterfly species. Implications for Insect Conservation: Based on our study and other recent research from the common pastures, we recommend to maintain the current grazing regime to foster biodiversity in general and M. dryas in particular. Additionally, where possible, abandoned fens and transition mires adjacent to common pastures should be integrated into the low-intensity pasture systems. The preservation of traditionally managed litter meadows is the second important possibility to conserve M. dryas populations. [ABSTRACT FROM AUTHOR]

Xanthogaleruca luteola (Müller) is a monophagous pest species indigenous to Europe, known as elm leaf beetle. During the larval and adult stages, this insect damages elm leaves as it chews small holes in the leaves, causing, even, complete defoliation, leaving only the nervation. Although this species only uses Ulmus spp. as host plants to complete its development, some preliminary results have shown that is attracted to non-host plants such as Eucalyptus globulus Labill. In order to understand the role of volatile organic compounds emitted by E. globulus when the insect is attracted to this non-host plant, dichloromethane extracts of E. globulus were analyzed through gas chromatography-mass spectrometry, and main compounds were identified. Likewise, to evaluate the response of the antennae in X. luteola males and females to the compounds contained in the extract, a gas chromatographic-electroantennographic detection (GC-EAD) was conducted. Only females were observed to respond to a-pinene, eucalyptol, 4-terpineol, a-terpineol, a-terpineol acetate, a-gurjunene, alloaromadendrene, alloaromadendrene, viridiflorene, and globulol compounds. This study is the first step to identify substances mediating the host plant selection of X. luteola. [ABSTRACT FROM AUTHOR]

Many exotic pine species are planted in Europe. These pines are tested for resistance to ozone, sulfur dioxide, drought and frost. However, their resistance can be reduced by bark beetles. In Poland the bark beetles Pityophthorus pityographus and Pityophthorus lichtensteinii were detected on Pinus armandi and Pinus ×schwerinii pines. In Europe these are the first findings of bark beetles on these trees and, at the same time, new host plants for these bark beetles. [ABSTRACT FROM AUTHOR]

The strawberry blossom weevil (SBW), Anthonomus rubi, is a major pest in strawberry fields throughout Europe. Traps baited with aggregation pheromone are used for pest monitoring. However, a more effective lure is needed. For a number of pests, it has been shown that the attractiveness of a pheromone can be enhanced by host plant volatiles. The goal of this study was to explore floral volatile blends of different strawberry species (Fragaria x ananassa and Fragaria vesca) to identify compounds that might be used to improve the attractiveness of existing lures for SBW. Floral emissions of F. x a. varieties Sonata, Beltran, Korona, and of F. vesca, were collected by both solid-phase microextraction (SPME) and dynamic headspace sampling on Tenax. Analysis by gas chromatography/mass spectrometry showed the floral volatiles of F. x ananassa. and F. vesca were dominated by aromatic compounds and terpenoids, with 4-methoxybenzaldehyde (p-anisaldehyde) and α-muurolene the major compounds produced by the two species, respectively. Multi-dimensional scaling analyses separated the blends of the two species and explained differences between F. vesca genotypes and, to some degree, variation between F. x ananassa varieties In two-choice behavioral tests, SBW preferred odors of flowering strawberry plants to those of non-flowering plants, but weevils did not discriminate between odors from F. x ananassa and F. vesca flowering plants. Adding blends of six synthetic flower volatiles to non-flowering plants of both species increased the preference of SBW for these over the plants alone. When added individually to non-flowering plants, none of the components increased the preference of SBW, indicating a synergistic effect. However, SBW responded to 1,4-dimethoxybenzene, a major component of volatiles from F. viridis, previously found to synergize the attractiveness of the SBW aggregation pheromone in field studies. [ABSTRACT FROM AUTHOR]

Exotic ambrosia beetles are increasing in Europe due to global trade and global warming. Among these xylomycetophagous insects, Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae) is a serious threat for several Mediterranean host plants. Carob trees growing in Sicily (Italy) have been extensively attacked by beetles leading to rapid tree decline. Although X. compactus has been found in Europe for several years, most aspects of its ecology are still unknown. We thus studied the population structure and dynamics of X. compactus, together with its twig size preference during a sampling of infested carob trees in south east Sicily. In addition, fungi associated with insects or galleries were isolated and characterized. The results showed that, in this newly-colonized environment and host plant, adult X. compactus overwinters inside twigs and starts to fly and reproduce in mid spring, completing five generations before overwintering in late fall. The mean diameter of carob twigs infested by the beetle varied significantly over the seasons, with the insect tending to infest larger twigs as season progresses. The mean number of adults/gallery was 19.21, ranging from 6 to 28. The minimum temperature significantly affected the overwintering adult mortality. Ambrosiella xylebori and Fusarium solani were the main symbionts associated with the pest in this study. Acremonium sp. was instead recorded for the first time in Europe inside X. compactus galleries. Several other fungi species were also found for the first time in association with X. compactus. Our findings provide useful insights into the sustainable management of this noxious pest. [ABSTRACT FROM AUTHOR]

Drosophila suzukii is an invasive pest which became a serious threat to stone and berry fruit production in Europe. Knowledge about the host range of this pest and the effect of the succession of available hosts over time is however lacking in vineyard landscapes. Our study aimed to evaluate the host range of D. suzukii throughout the year in a vineyarddominated area. We assessed egg deposition and emergence on nine wild and cultivated plant species sampled in twenty vineyard landscapes during two years. The temporal dynamics of D. suzukii presence was observed on five fruit species (Viscum album L., Prunus avium L., Sambucus nigra L., Rubus fruticosus L. aggr. and Vitis vinifera L. cv. Merlot) with different phenologies. Infestations on host plants depended on the season and the proportion of other fruits species in the landscape around the vineyard plots. The data collected enabled us to provide estimates of the population dynamics among different hosts and generations of the pest and to propose a pattern of temporal succession of host plant species adapted to our regional and agroecological context. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is an important crop disease worldwide and is mainly caused by members of the Fusarium graminearum species complex. F. graminearum sensu stricto is the most common cosmopolitan and predominant FHB causal agent in Europe. Thus far, the majority of studies have focused on the primary hosts (wheat and barley) of this pathogen, while the relationships between other sources of infection remain unclear. We monitored and sampled test fields over the course of 3 years and acquired 804 F. graminearum isolates from different sources: primary hosts and other plant species included in the crop rotations, weeds from the test fields, decaying plant residue, soil samples, and crop seed. Of these isolates, 73.3% had the 15-acetyldeoxynivalenol genotype and 26.7% had the 3-acetyldeoxynivalenol genotype. F. graminearum isolation rates from weeds (>50%) were much higher than from soil (< 10%) or decaying plant matter (4%). Variable number of tandem repeat markers were used for population analysis. Noticeable genetic differentiation was detected between isolates from living plants and soil biome. In contrast, absence of any noticeable division between primary and alternative plant host communities indicates the importance of weeds and other segetal plants for FHB control and prevention. [ABSTRACT FROM AUTHOR]

Phengaris alcon is an endangered butterfly that is subject to several conservation programs in Europe. Our study aims at evaluating how grazing pressure by domestic animals affects the maintenance of Gentiana pneumonanthe stems, larval plant host of Phengaris alcon and the survival of Phengaris alcon's eggs. We selected 304 stems of G. pneumonanthe (including 125 with P. alcon eggs) that were distributed over 4 ungrazed plots and 18 plots grazed by cattle or horses, for which we collected a grazing pressure index (Livestock Units days grazed ha−1). We monitored each stem over seven sampling sessions at 10 days intervals during the summer (from 02 July to 12 September 2018). We demonstrated that the G. pneumonanthe stems browsing probability was two times higher in the grazed plots than in the ungrazed plots. The number of eggs sharply decreased in the grazed plots, whereas it remained constant in the ungrazed plots during successive sampling sessions. Grazing, even at low intensity (10 LU days grazed ha−1), induced defoliation of G. pneumonanthe stems. The probability of the maintenance of G. pneumonanthe stems and the probability of survival of P. alcon eggs is close to zero above 20 LU days grazed ha−1. In order to protect the P. alcon population, we recommend extensive and early grazing (before mid-July) before the growth of G. pneumonanthe stems, or late grazing (after early September) avoiding the development period of G. pneumonanthe, the oviposition period and the early caterpillar development of P. alcon. Alternatively, we suggest the establishment of temporary exclosures on high densities areas of G. pneumonanthe between mid-July to early September. [ABSTRACT FROM AUTHOR]

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae) is a vector of the bacterium that causes huanglongbing (HLB), a disease heavily impacting citrus production in many areas worldwide. Neither the psyllid nor the disease have been found in the Mediterranean yet, where citrange Carrizo (Citrus sinensis Osb. x Poncirus trifoliata L. Raf.) is extensively used as citrus rootstock. This study evaluated the suitability of this rootstock as a host for D. citri in both laboratory and greenhouse conditions. The suitability of sour orange (Citrus aurantium L.) (highly susceptible) and trifoliate orange (Poncirus trifoliata L. Raf.) (highly resistant) was also assessed. Host suitability was determined based on host plant selection, oviposition, and survival of D. citri. Under laboratory conditions the psyllid preferentially chose and oviposited on citrange Carrizo and sour orange rather than on P. trifoliata. Greenhouse experiments demonstrated that oviposition on P. trifoliata was nil and provided evidence that citrange Carrizo is an extremely favorable host for D. citri development and reproduction. This information is important for the Mediterranean region, where HLB could prove devastating for the citrus industry because of the widespread use of citrange Carrizo as rootstock. [ABSTRACT FROM AUTHOR]

The most likely scenarios for Xylella fastidiosa introduction in Central Europe is through infected ornamental plants, with a successive spillover from gardens and parks to cultivated orchards. Given its polyphagy and wide distribution, the meadow spittlebug Philaenus spumarius, the only ascertained vector of X. fastidiosa in Europe so far, might play an important role in such a scenario. Here, we combined and analyzed spittlebug's behavioral data obtained through Electrical Penetration Graph (EPG), preference and survival tests as well as field surveys, in order to infer possible bacterium patterns of spread. For our case study, we selected oleander and rosemary as potential introductory hosts and grapevine and cherry as economically important threatened plants. Philaenus spumarius was collected in field near all the four plant species, although choice and no-choice tests indicated that the spittlebug rather prefers to settle on cherry and grapevine than on rosemary and oleander. Considering the results of the EPG, the duration of xylem sap ingestion was longer in cherry, grapevine and rosemary than in oleander. However, P. spumarius spent on rosemary most of the time in resting activities, this implying a lower duration of xylem sap ingestion compared to grapevine and cherry. Overall, our data suggest that cultivated plants as grapevine and cherry could be more relevant than oleander and rosemary as X. fastidiosa source plants; therefore, P. spumarius might acquire the bacterium from cultivated plants, then first spread it within cultivated orchards, and successively to ornamental plants during its dispersal. [ABSTRACT FROM AUTHOR]

Xylella fastidiosa (Xf) is an insect-borne bacterium confined to the xylem vessels of plants. This plant pathogen has a broad host range estimated to 560 plant species. Five subspecies of the pathogen with different but overlapping host ranges have been described, but only three subspecies are widely accepted, namely subspecies fastidiosa , multiplex , and pauca. Initially limited to the Americas, Xf has been detected in Europe since 2013. As management of X. fastidiosa outbreaks in Europe depends on the identification of the subspecies, accurate determination of the subspecies in infected plants as early as possible is of major interest. Thus, we developed various tetraplex and triplex quantitative PCR (qPCR) assays for X. fastidiosa detection and subspecies identification in planta in a single reaction. We designed primers and probes using SkIf, a bioinformatics tool based on k -mers, to detect specific signatures of the species and subspecies from a data set of 58 genome sequences representative of X. fastidiosa diversity. We tested the qPCR assays on 39 target and 30 non-target strains, as well as on 13 different plant species spiked with strains of the different subspecies of X. fastidiosa , and on samples from various environmental and inoculated host plants. Sensitivity of simplex assays was equal or slightly better than the reference protocol on purified DNA. Tetraplex qPCR assays had the same sensitivity than the reference protocol and allowed X. fastidiosa detection in all spiked matrices up to 103 cells.ml−1. Moreover, mix infections of two to three subspecies could be detected in the same sample with tetraplex assays. In environmental plant samples, the tetraplex qPCR assays allowed subspecies identification when the current method based on multilocus sequence typing failed. The qPCR assays described here are robust and modular tools that are efficient for differentiating X. fastidiosa subspecies directly in plant samples. [ABSTRACT FROM AUTHOR]

Orientus ishidae (Matsumura) (subfamily Deltocephalinae) is an Asian species now widespread in Europe, and a vector of 16SrV phytoplasmas agents of grapevine Flavescence dorée (FDP). Embryonic and post-embryonic development, spatial distribution, and relationships with grapevine of nymphs were studied under field and laboratory conditions. Egg-hatching dynamics and post-embryonic development of nymphs were studied by collecting grapevine wood from managed and unmanaged vineyards (including bot European Vitis vinifera L. and wild American rootstocks) and storing it inside rearing cages at T = 21–23°C. Field sampling of nymphs were made on both grapevine and two elective host plants of O. ishidae: hazelnut and hornbeam. Taylor's Power Law was applied to assess the aggregation coefficient of early- (first and second) and late- (third to fifth) life instars on leaves and shoots of host plants. More nymphs were obtained from wood collected in unmanaged rather than managed vineyards. Under lab conditions, the embryonic development lasted 34–48 d, whereas the whole post-embryonic development averaged 27 d. Under field conditions, early instars peaked at the end of May, and late instars peaked 2–4 wk later. The aggregation patterns decreased from early to late instars, and from leaves to shoots. Very few nymphs were observed on unmanaged grapevine, either European or American, and none on managed European grapevine. Some behavioral and FDP epidemiological consequences of the results obtained are discussed. [ABSTRACT FROM AUTHOR]

The genera Eumerus and Merodon (Syrphidae: Merodontini) form together the most speciose grouping of hoverflies in the Palaearctic Region. However, little is known about the morphology and biology of their larvae. The few larvae of Eumerus and Merodon that have been uncovered are phytophagous in underground organs of plants (some Eumerus and all Merodon) or saprophagous in a variety of plants' parts (the reminder of Eumerus). In this study, the second larval stage (L2) of Eumerus lyneborgi Ricarte & Hauser, 2020 and both the larva (L2) and puparium of Merodon constans (Rossi, 1794) are described for the first time. Larvae of E. lyneborgi were found in a decaying stem of Cyphostemma juttae (Dinter & Gilg) Desc., 1960 (Vitaceae) in Namibia (Africa), while larvae of M. constans were collected in bulbs of Leucojum vernum Linnaeus, 1753, (Amaryllidaceae) in France (Europe). Morphology of the immature forms was studied by observation and imaging with stereomicroscopy and scanning electron microscopy. The head skeleton of E. lyneborgi larvae was found to be of the filter feeding type, i.e., in accordance with a saprophagous trophic regime, while that of M. constans was typically phytophagous. Variability in certain characters of the M. constans early stages is described and discussed in relation to the adult form and molecular information published in literature. An updated identification key to all known third larval stages/puparia of Merodon is provided., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Both close inbreeding and distant outbreeding may reduce fitness below the level of individuals with intermediate parental relatedness. In the haplodiploid plant-inhabiting predatory mite Phytoseiulus persimilis, which is patchily distributed within and among host plants, fitness is indeed reduced in the short term, i.e. by a single generation of inbreeding. However, in the medium to long term (multiple generations), distant out-breeding should provide for favorable demographic founder effects in isolated populations. We tested this prediction in isolated experimental lineages founded by females mated to a sibling (close inbreeding), a male from the same population (intermediate relatedness) or a male from another population (distant outbreeding) and monitored lineage growth and persistence over four generations. Cross-generationally, lineages founded by distantly outbred females performed the best, i.e. produced the most descendants. However, this was solely due to superior performance from the F2 generation onwards, whereas in the F1 generation, lineages founded by females mated to males from their own population (intermediate relatedness) performed the best, as predicted from short-term in- and out-breeding depression effects. At the genetic level, this result was most likely due to distantly outbred founders introducing higher allelic variability and lower homozygosity levels, counterbalancing inbreeding depression, which inevitably occurs in isolated lineages, from the F2 generation onwards. [ABSTRACT FROM AUTHOR]

During a recent survey on insect pests of ornamental plants in Spain, the leafhoppers Chloropelix canariensis Lindberg 1936 and Balclutha brevis Lindberg 1954 (Hemiptera, Cicadellidae) were found. These species, described from Canary Island, are recorded here for the first time from Spain and continental Europe. Adults and immature stages of C. canariensis and B. brevis have been found associated with Pennisetum setaceum (Forsskal) Chiovenda (Poaceae) practically all the year round. Emergence period of the adults, morphological features, and some biological notes are provided to C. canariensis. Furthermore, a review is given on alien Auchenorrhyncha species introduced in Europe. From literature, 30 species have been accidentally introduced, representatives of the following seven families: Delphacidae (1 sp.), Issidae (1 sp.), Acanaloniidae (1 sp.), Flatidae (1 sp.), Ricaniidae (3 spp.), Membracidae (1 sp.), Cicadellidae (22 spp.). Four species previously erroneously or equivocally cited for Europe as alien species must be excluded from the list. Details on the first record and country in Europe, the year of publication of the first record, original distribution, current distribution and host plants are given for each species. [ABSTRACT FROM AUTHOR]

African citrus greening (ACGD) and huanglongbing (HLB) diseases are the most damaging diseases of citrus worldwide. Currently, the disease has no cure and has been attributed to the collapse of the citrus industry in several countries. In Africa, the causative agent "Candidatus" Liberibacter africanus is vectored by African citrus triozid (ACT) Trioza erytreae Del Guercio (Hemiptera: Triozidae). African citrus triozid is native to Africa but has been recently reported in Asia and Europe. Apart from citrus, Murraya koenigii (L.) and Clausena anisata (Willd) Hook. F. ex Benth. are also considered as preferred host plants. At present, there is scant information on host plant suitability and preference of T. erytreae. Also, there are contradictory reports on its reproduction and survival on rutaceous and non‐rutaceous host plants. In the present study, we tested the suitability and preference of rutaceous and non‐rutaceous trees and shrubs as potential ACT host plants in choice and no‐choice bioassays. The development from egg to the adult stage was longest on Calodendrum capense (Wright & Arn.) Engl. Host plants of superior quality accordingly to several ACT's biological parameters measured also revealed significantly higher morphometric characteristics. Our findings on the host status of the five rutaceous plants imply that these plants can greatly influence the population dynamics of ACT as well as the epidemiology of ACGD, and these can be a useful guide in the area‐wide management of the pest in Kenya. [ABSTRACT FROM AUTHOR]

The pathogenic fungus Sclerotinia sclerotiorum infects over 600 species of plant. It is present in numerous environments throughout the world and causes significant damage to many agricultural crops. Fragmentation and lack of gene flow between populations may lead to population sub-structure. Within discrete recombining populations, positive selection may lead to a ‘selective sweep’. This is characterised by an increase in frequency of a favourable allele leading to reduction in genotypic diversity in a localised genomic region due to the phenomenon of genetic hitchhiking. We aimed to assess whether isolates of S. sclerotiorum from around the world formed genotypic clusters associated with geographical origin and to determine whether signatures of population-specific positive selection could be detected. To do this, we sequenced the genomes of 25 isolates of S. sclerotiorum collected from four different continents–Australia, Africa (north and south), Europe and North America (Canada and the northen United States) and conducted SNP based analyses of population structure and selective sweeps. Among the 25 isolates, there was evidence for two major population clusters. One of these consisted of 11 isolates from Canada, the USA and France (population 1), and the other consisted of nine isolates from Australia and one from Morocco (population 2). The rest of the isolates were genotypic outliers. We found that there was evidence of outcrossing in these two populations based on linkage disequilibrium decay. However, only a single candidate selective sweep was observed, and it was present in population 2. This sweep was close to a Major Facilitator Superfamily transporter gene, and we speculate that this gene may have a role in nutrient uptake from the host. The low abundance of selective sweeps in the S. sclerotiorum genome contrasts the numerous examples in the genomes of other fungal pathogens. This may be a result of its slow rate of evolution and low effective recombination rate due to self-fertilisation and vegetative reproduction. [ABSTRACT FROM AUTHOR]

This paper presents the European distribution of the understudied, host-specific rust fungus, Uromyces erythronii (Pucciniomycetes, Pucciniales, Pucciniaceae). Distribution data were derived from the survey of herbarium materials of its European host plant, Erythronium dens-canis. We demonstrate the presence of this rust fungus in 14 countries within the distribution area of its host. The temporal trend of emergence of the two rust fungus generations (aecia and telia) is presented. Based on the study of 1700 E. dens-canis individuals, we conclude that the overall infection rate has not changed significantly over the last 200 years. During field surveys, U. erythronii infection was detectable in most of the studied Erythronium populations (88.5%). A high similarity in the nrITS region was detected among samples from Europe (Croatia, Romania) and Asia (Japan). Citation: Nagy T., Pfliegler W. P., Takács A., Tökölyi J. & Molnár V. A. 2019: Distribution, infection rates and DNA barcoding of Uromyces erythronii (Pucciniaceae), a parasite of Erythronium (Liliaceae) in Europe. – Willdenowia 49: 13–20. doi: https://doi.org/10.3372/wi.49.49103 Version of record first published online on 14 March 2019 ahead of inclusion in April 2019 issue. [ABSTRACT FROM AUTHOR]

The genus Aleurocanthus Quaintance & Baker, 1914 comprises about 80 species worldwide, several of which are of economic importance for crops including Aleurocanthus woglumi and A. spiniferus. During import interceptions A. camelliae , a look-alike of the former species, has occasionally been found on imported Camellia bonsai, pot plants and shrubs in the Netherlands. Living populations of this species may be locally found on imported and traded plants in the EPPO region. In Europe all species of the genus Aleurocanthus are regulated, which makes early recognition necessary. A reliable identification is needed to take adequate measures that prevent the establishment and spread of newly intercepted species in Europe. A key is given to related genera and to developmental stages, together with an overview of field views of puparia and the main discriminating morphological and microscopic characters of both adult and pre-adult stages of three species. Since 2008, A. spiniferus is established in southern Italy and is spreading, both in Italy and in surrounding countries in the Mediterranean region, causing severe economic and ecological damage not only to the Citrus culture but because of its polyphagy to many other host plants as well. The early recognition of species newly introduced into Europe is complicated by the loss of taxonomical knowledge and the diminishing number of taxonomic workers. A revision of the genus should include the delimitation of the genus, separating it from related genera, the (re)description of the intraspecific variation of known species and the description of newly collected species by molecular techniques and morphological methods. [ABSTRACT FROM AUTHOR]

Soil is one of the most essential life-supporting environments. The processes that define these environments' structures over time and space are still poorly understood. In order to contribute to elucidating the dynamics of microbial communities in soil with different fertility levels, this study analyzes 197 rhizosphere microbiome samples obtained from different soil types, available in six articles. Data from amplicon sequencing analyses were extracted from the articles and 15 main prokaryotic phyla were identified. Soil physical and chemical characteristics enabled to classify soils as poor, medium, and rich. The SIMPER test showed that prokaryotic communities presented approximately 40 % of dissimilarities when comparing three levels of soil fertility. Proteobacteria, Acidobacteria, and Actinobacteria were the dominant phyla, accounting for 58 % of total OTUs in poor, 54 % in medium, and 47 % in rich soils. However, Verrucomicrobia, Gemmatimonadetes, and Elusimicrobia phyla that seem to present a central importance in the microbial distributions. The relative abundance profile of the main phyla was better separated according to soil fertility level than plant host. Clay, organic matter, pH, K, and P availability show significant linear correlations with some phyla studied. In conclusion, soil physical and chemical characteristics are the main influencers of relative abundance of some prokaryotic phylum. The high diversity of prokaryotic communities present in the plant rhizosphere systems seems to be shifted mainly by soil characteristics. • Review and meta-analysis of 197 soils samples regarding microbial communities • Prokaryotic communities at phyla level change according to soil fertility. • Soil physicochemical characteristics, not plant species, are the main modulator of soil prokaryotic communities. • Soil pH seems to be most important characteristic to shape microbial community. • Verrucomicrobia, Gemmatimonadetes, and Elusimicrobia phyla seem to have a central importance in distributions. [ABSTRACT FROM AUTHOR]

The nearctic moth Acontia candefacta (Lepidoptera Noctuidae) is expanding its range in Europe. The species is considered a successful agent for biological control of Ambrosia artemisiifolia (Asterales Asteraceae), a weed whose pollen causes allergies in humans. A few additional findings of the moth have been recorded at several new sites in southeastern Europe (Serbia) using light trapping. We here present and discuss the current distribution of the moth in Europe and the paths of its spreading on the basis of GIS data. GIS technology was used to map the distribution and quantify values of environmental variables within the range of the analysed moth species. Additionally, the potential colonization of the moth across Europe is modelled on the basis of its current distribution, environmental variables and the host plant's distribution. [ABSTRACT FROM AUTHOR]

The Special Collection 'Spodoptera frugiperda (fall armyworm): Ecology and Management of its World-scale Invasion Outside of the Americas' presents reviews and research that address topics of overarching interest and contributes to a better understanding of this pest and its management, now that it has spread outside the Americas. The collection is a combination of invited articles presenting new information published for the first time, invited review papers, and a selection of relevant high-quality articles previously published in Journal of Economic Entomology (JEE). Articles in the Collection, as well as selected citations of articles in other publications, reflect the increase in research on S. frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), which became the most important pest of maize in the world during recent years. This Special Collection addresses a wide range of topics, including pest behavior, host strains, insecticide and Bt protein resistance, biological control, host plant resistance, and yield loss estimates. Topics are presented in context of research primarily conducted in regions outside of the Americas where S. frugiperda has invaded and disrupted crop production to varying degrees. In recognition of further spread, the threat of a S. frugiperda invasion into Europe and potential management options are also presented. [ABSTRACT FROM AUTHOR]

The oak wilt fungus, Ceratocystis fagacearum, is native to North America, and is a threat to oaks in Europe. Therefore, the European Union has regulated the importation of oak wood from the US into Europe. We developed a pathway model to calculate the exposure of oak trees in Europe to the fungus under different regulatory scenarios and thus evaluate the effectiveness of the measures. The model describes the import, inspection and treatments of wood, as well as the trade among European countries and processing to sawn wood, final product and residues. The model quantifies the frequency of escape of the fungus from wood with a vector, and the transfer to host trees. Existing regulations reduce exposure by a factor >30 000 compared with a scenario without regulation. Exposure is highest around European ports and during transportation of wood across Europe. Wood treatments and shipment to a restricted set of ports are effective measures, each reducing exposure by more than 90%. Pathway modelling is a promising tool to study entry pathways of alien tree pests and evaluate risk reduction options: it provides a systematic and transparent approach but is limited by availability of biological data. [ABSTRACT FROM AUTHOR]

The introduced black locust ( Robinia pseudoacacia ) has become an invasive plant species in Europe. The introduction of alien plants such as the black locust may modify ecosystem composition and functioning. In response to the presence of a potential host plant, herbivores can adapt and shift to the consumption of the new host plant. In Eastern-Central Europe, the seed predator Bruchophagus robiniae (Hymenoptera: Eurytomidae ) is an important consumer of black locust seeds which presumably shifted from its formerly host species to black locust. We tested the influence of host plant abundance on a seed predator – parasitoid community. We found that the seed predator B. robiniae was present in higher numbers in woodlots than in small patches of black locust. The density of the specialist parasitoid Mesopolobus sp. was lower in woodlots than in small patches, while the generalist parasitoid Eupelmus urozonos was evenly distributed between woodlots and small patches of black locust. We found that parasitoid species are influenced by the patch size of host plants, thus characteristics of introduced host plants can also manifest in higher trophic levels. [ABSTRACT FROM AUTHOR]

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