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Introduction: Room air class (RC) Ib may be necessary for surgiccedures in aseptic working areas. The aim of the study was to examine whether a mobile, three-stage sterile ventilation unit (MSVU) can replace a room ventilation system (RVS) with turbulent mixed flow (TMF) in the area of the operating field and on the instrument table from hygienic-microbiological point of view. Method: During 26 surgeries (varicose vein stripping or treatment of umbilical and inguinal hernias), the microbial load was recorded at easuring points (M1–M4) during regular operations by setting up sedimentation plates and measuring the particle concentration. Measuring points M1 and M2 were located at the beginning and the end of the instrument table, measuring point M3 next to the operating field and measuring point M4 outside the sterilely ventilated area approx. 135 cm from the operating field. The measured values were compared with results with simulated, incorrect positioning and with MSVU not switched on. Results: The number of people and the duration of the operation differ between the 3 measurement situations.The MSVU achieved a significant reduction in the number of sedimented colony-forming units (CFU) at M1 by 88.4%, at M2 by 91.5% and at M3 by 65.2%. At measuring point M4, the values did not differ between MSVU switched on or off. Even with an unacceptably increased distance between the MSVU and the instrument table, the difference at measuring points M1, M2 and M3 was still significant in comparison with MSVU switched off. Coagulase-negative staphylococci were predominantly detected, followed by and apathogenic spore-forming bacteria, but Gram-negative bacteria were not detected in any cases. The number of CFU detected fulfils the criteria for conventionally turbulent non-directionally ventilated surgical units with TMF of RC Ib.The particle count was reduced by an average of 66%. As comparable particle counts were found in the aseptic working area in a separately conducted study in an RC Ib surgical unit, it can be assumed that the results obtained with the MSVU are hygienically safe. Conclusion: With the MSVU, a reduction of the microbial load and the particle count in the room air was achieved in the area of the operating field and on the instrument table during operation in an RC II surgical unit, which can be categorised as sufficient for operations in RC Ib. With the aid of an MSVU, operations with a high risk of surgical sire infections can also be carried out in surgical units of RC II from hygienic-microbiological point of view. The MSVU is an organisationally flexible and economically interesting, safe and sustainable option in terms of the microbiological load and particle count in the operating field and instrument table instead of an RVS that ventilates the entire room. In times of increasing outpatientisation of surgical services, MSVU is a promising option for outpatieurgical units in particular.

Simple Summary: Scaphoideus titanus is the main transmission vector Flavescence doreé (FD) in Europe, causing significant damage to grapevine production. The causative agent of FD is the bacterium 'Candidatus Phytoplasma vitis'. However, little is known about the interaction of this plant pathogen with the bacterial communities within the insect host. In this study, we characterize the bacterial communities in S. titanus across different European populations and different life stages. We found significant differences in the microbial composition across different populations but did not observe any differences between nymphs and adults of the same population. The Nearctic leafhopper Scaphoideus titanus (Hemiptera: Cicadellidae) is the primary vector of 'Candidatus Phytoplasma vitis', the causative agent of Flavescence doreé in Europe. Although microorganisms play an important role in the ecology and behavior of insects, knowledge about the interaction between S. titanus and microbes is limited. In this study, we employed an amplicon metabarcoding approach for profiling the V4 region of the 16S rRNA gene to characterize the bacterial communities of S. titanus across several populations from four European localities. Additionally, we investigated changes in bacterial communities between nymphal and adult stages. In total, we identified 7,472 amplicon sequence variants (ASVs) in adults from the European populations. At the genus level, 'Candidatus Karelsulcia' and 'Candidatus Cardinium' were the most abundant genera, with both being present in every individual. While we found significant changes in the microbial composition of S. titanus across different European populations, no significant differences were observed between nymphal and adult stages. Our study reveals new insights into the microbial composition of S. titanus and highlights the role of geography in influencing its bacterial community. [ABSTRACT FROM AUTHOR]

The introduction of non‐native species across the world represents a major global challenge. Retracing invasion origin is an important first step in understanding the invasion process, often requiring detailed sampling within the native range. Insect species frequently host Wolbachia, a widespread endosymbiotic bacterium that manipulates host reproduction to increase infected female fitness. Here, we draw on the spatial variation in infection frequencies of an actively spreading Wolbachia strain wCer2 to investigate the invasion origin of the European cherry fruit fly, Rhagoletis cerasi. This pest of cherries was introduced from Europe to North America within the last decade. First, we screen the introduced fly population for the presence of Wolbachia. The introduced populations lack the wCer2 strain and the strongly associated mitochondrial haplotype, suggesting strain absence due to founder effects with invading individuals originating from wCer2‐uninfected native population(s). To narrow down geographic regions of invasion origin, we perform spatial interpolation of the wCer2 infection frequency across the native range and predict the infection frequency in unsampled regions. For this, we use an extensive dataset of R. cerasi infection covering 238 populations across Europe over 25 years, complemented with 14 additional populations analyzed for this study. We find that R. cerasi was unlikely introduced from wCer2‐infected populations in Central and Western Europe. We propose wCer2‐uninfected populations from Eastern Europe and the Mediterranean region as the most likely candidates for the invasion origin. This work utilizes Wolbachia as an indirect instrument to provide insights into the invasion source of R. cerasi in North America, revealing yet another application for this multifaceted heritable endosymbiont. Given the prevalence of biological invasions, rapidly uncovering invasion origins gives fundamental insights into how invasive species adapt to new environments. [ABSTRACT FROM AUTHOR]

The relationship between phytophagous insects and plants is a central aspect of food webs and ecosystem functioning. The introduction of new species into an environment can have significant impacts on the food web of a native ecosystem. In many cases, there is a lack of knowledge on the biology and feeding behavior of invasive species prior their introduction and in the invaded regions. Gut content analyses of insects have provided valuable information on the host spectrum of insects. However, current approaches are time‐consuming and costly. Here, we describe a new molecular gut content analysis (GCA) approach using the Oxford Nanopore (ONT) Flongle sequencing platform to characterize the plant DNA present in the gut of the highly polyphagous insect species Halyomorpha halys. We demonstrate that this technique efficiently amplifies and correctly identifies plant DNA in a mock community. We performed a feeding experiment to determine the sensitivity of this approach and to assess how long the plant DNA can be detected. All plants used in the feeding experiment were correctly identified and detected after 56 days. Surprisingly, we also detected various plant genera that were not included in the feeding experiment and thus were likely ingested months before the experiment. Our study suggests that the GCA using the ONT Flongle sequencing platform represents a rapid and cost‐efficient diagnosis of the dietary preferences, host range, and the diversity of consumed plant species of pest insects with high precision. [ABSTRACT FROM AUTHOR]

Simple Summary: Correct taxonomic identification is essential for conducting successful biological research, especially with regard to economically important insects, such as jumping plant lice or psyllids. In the present study, we identify and diagnose the morphologically characterised aphalarid species from Bulgaria using two molecular markers, cytochrome c oxidase I and cytochrome b. A total of 80 sequences of 25 Aphalaridae species were obtained and included in the BOLD and GenBank databases. This should enable even non-experts to identify these species quickly and accurately. The results of the current study show that two barcode genes are sufficient to distinguish most aphalarid species. Psyllids (Hemiptera: Psylloidea) are plant sap-sucking insects whose identification is often difficult for non-experts. Despite the rapid development of DNA barcoding techniques and their widespread use, only a limited number of sequences of psyllids are available in the public databases, and those that are available are often misidentified. Here, we provide 80 sequences of two mitochondrial genes, cytochrome c oxidase I (COI) and cytochrome b (Cytb), for 25 species of Aphalaridae, mainly from Bulgaria. The DNA barcodes for 15 of these species are published for the first time. In cases where standard primers failed to amplify the target gene fragment, we designed new primers that can be used in future studies. The distance-based thresholds for the analysed species were between 0.0015 and 0.3415 for COI and 0.0771 and 0.4721 for Cytb, indicating that the Cytb gene has a higher interspecific divergence, compared to COI, and therefore allows for more accurate species identification. The species delimitation based on DNA barcodes is largely consistent with the differences resulting from morphological and host plant data, demonstrating that the use of DNA barcodes is suitable for successful identification of most aphalarid species studied. The phylogenetic reconstruction based on maximum likelihood and Bayesian inference analyses, while showing similar results at high taxonomic levels to previously published phylogenies, provides additional information on the placement of aphalarids at the species level. The following five species represent new records for Bulgaria: Agonoscena targionii, Aphalara affinis, Colposcenia aliena, Co. bidentata, and Craspedolepta malachitica. Craspedolepta conspersa is reported for the first time from the Czech Republic, while Agonoscena cisti is reported for the first time from Albania. [ABSTRACT FROM AUTHOR]

The bark beetle Ips typographus (L.) is the most important pest in European Norway spruce forests. Especially after abiotic disturbance events, like storms or snowfall, this beetle can utilise vast amounts of trees with impaired defences, leading to mass outbreaks and further mortality of spruce. In 2018, the 'Vaia' storm damaged huge areas of Norway spruce-dominated forests in the Southern Alps. In the following years, the same regions were additionally affected by heavy snowfalls providing high amounts of suitable material for I. typographus brood establishment and development. Since then, these forests have faced unprecedented population outbreaks of I. typographus with severe effects for forest ecosystems, from both an ecological and an economic perspective. A comprehensive understanding of this beetle's genetic structure, including effects of the last ice ages as well as consequences of current population outbreaks, can give insights into the population dynamics of an eruptive species. Here, we studied the genetic structure of five epidemic populations from the Southern Alps and one from a potential glacial refugium in the Apennines. Our results revealed a low genetic diversity and a weak population structure among all studied locations. In the six analysed populations, four already described haplotypes, belonging to three slightly divergent haplogroups, were found. These haplotypes were evenly distributed among populations, including the potential glacial refugium in the Apennines. High gene flow among populations is probably maintained by the beetle's high dispersal capacity and high population densities, resulting in a panmictic population structure. [ABSTRACT FROM AUTHOR]

Endosymbiont‐induced cytoplasmic incompatibility (CI) may play an important role in arthropod speciation. However, whether CI consistently becomes associated or coupled with other host‐related forms of reproductive isolation (RI) to impede the transfer of endosymbionts between hybridizing populations and further the divergence process remains an open question. Here, we show that varying degrees of pre‐ and postmating RI exist among allopatric populations of two interbreeding cherry‐infesting tephritid fruit flies (Rhagoletis cingulata and R. indifferens) across North America. These flies display allochronic and sexual isolation among populations, as well as unidirectional reductions in egg hatch in hybrid crosses involving southwestern USA males. All populations are infected by a Wolbachia strain, wCin2, whereas a second strain, wCin3, only co‐infects flies from the southwest USA and Mexico. Strain wCin3 is associated with a unique mitochondrial DNA haplotype and unidirectional postmating RI, implicating the strain as the cause of CI. When coupled with nonendosymbiont RI barriers, we estimate the strength of CI associated with wCin3 would not prevent the strain from introgressing from infected southwestern to uninfected populations elsewhere in the USA if populations were to come into secondary contact and hybridize. In contrast, cytoplasmic–nuclear coupling may impede the transfer of wCin3 if Mexican and USA populations were to come into contact. We discuss our results in the context of the general paucity of examples demonstrating stable Wolbachia hybrid zones and whether the spread of Wolbachia among taxa can be constrained in natural hybrid zones long enough for the endosymbiont to participate in speciation. [ABSTRACT FROM AUTHOR]

Adaptation to novel environments can result in unanticipated genomic responses to selection. Here, we illustrate how multifarious, correlational selection helps explain a counterintuitive pattern of genetic divergence between the recently derived apple‐ and ancestral hawthorn‐infesting host races of Rhagoletis pomonella (Diptera: Tephritidae). The apple host race terminates diapause and emerges as adults earlier in the season than the hawthorn host race, to coincide with the earlier fruiting phenology of their apple hosts. However, alleles at many loci associated with later emergence paradoxically occur at higher frequencies in sympatric populations of the apple compared to the hawthorn race. We present genomic evidence that historical selection over geographically varying environmental gradients across North America generated genetic correlations between two life history traits, diapause intensity and diapause termination, in the hawthorn host race. Moreover, the loci associated with these life history traits are concentrated in genomic regions in high linkage disequilibrium (LD). These genetic correlations are antagonistic to contemporary selection on local apple host race populations that favours increased initial diapause depth and earlier, not later, diapause termination. Thus, the paradox of apple flies appears due, in part, to pleiotropy or linkage of alleles associated with later adult emergence and increased initial diapause intensity, the latter trait strongly selected for by the earlier phenology of apples. Our results demonstrate how understanding of multivariate trait combinations and the correlative nature of selective forces acting on them can improve predictions concerning adaptive evolution and help explain seemingly counterintuitive patterns of genetic diversity in nature. [ABSTRACT FROM AUTHOR]

The brown marmorated stink bug Halyomorpha halys is one of the most harmful invasive species in the world. Native to East Asia, this insect was introduced into North America in the 1990s and into Europe in the 2000s where it subsequently established and spread across the continent. Previous population genetic studies determined the invasion pathways at continental and national levels. However, information on the dynamics on a small-scale is currently scarce. Here we study the genetic diversity and population dynamics of H. halys in South Tyrol, a region in Northern Italy, since its arrival to its widespread establishment over a period of four years. By haplotyping 162 individuals from ten populations (including six previously published individuals) we found a high haplotype diversity in most populations with an increasing diversity across the different years. Most haplotypes were previously found in other regions of Northern Italy, providing evidence for migration from neighboring regions. However, the presence of four previously undescribed haplotypes as well as a haplotype previously found exclusively in Greece highlights additional long-distance dispersal across the continent. Phylogenetic analysis of the haplotypes found in South Tyrol showed that the majority of haplotypes clustered with haplotypes predominantly found in Japan. This suggests a potential recent introduction of H. halys individuals from Japan into Europe, and thus an additional invasion pathway that was previously unidentified. [ABSTRACT FROM AUTHOR]