Fakultät Naturwissenschaften

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Biologie, Ernährungs-wissenschaften und Lebensmittelwissenschaften sind die Schwerpunkte der Fakultät. Die Forschung befasst sich mit Schlüsselthemen der Life Sciences.

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Characterization of the major odor-active compounds in fresh rhizomes and leaves of Houttuynia cordata by comparative aroma extract dilution analysis
(2025) Xu, Zhenli; Liu, Jing; Kreissl, Johanna; Oellig, Claudia; Vetter, Walter; Steinhaus, Martin; Frank, Stephanie; Rodov, Victor
Houttuynia cordata is a culinary herb from Asia. Its edible rhizomes and leaves have a fishy aroma, the molecular background of which was unknown. A comparative aroma extract dilution analysis applied to fresh rhizomes and leaves resulted in 44 and 41 odorants, respectively, 38 of which were present with FD factors ≥1 in both samples. The odorant with the highest FD factors, whether in the rhizomes or leaves, was identified as metallic, soapy, fishy smelling 3-oxododecanal. Toward clarifying its tautomeric composition, quantum calculations suggested a predominance of the enol forms in the plant. However, the form perceived at the sniffing port during GC–O remained unclear.
Competitive hierarchies in bryozoan assemblages mitigate network instability by keeping short and long feedback loops weak
(2023) Koch, Franziska; Neutel, Anje-Margriet; Barnes, David K. A.; Tielbӧrger, Katja; Zarfl, Christiane; Allhoff, Korinna T.
Competitive hierarchies in diverse ecological communities have long been thought to lead to instability and prevent coexistence. However, system stability has never been tested, and the relation between hierarchy and instability has never been explained in complex competition networks parameterised with data from direct observation. Here we test model stability of 30 multispecies bryozoan assemblages, using estimates of energy loss from observed interference competition to parameterise both the inter- and intraspecific interactions in the competition networks. We find that all competition networks are unstable. However, instability is mitigated considerably by asymmetries in the energy loss rates brought about by hierarchies of strong and weak competitors. This asymmetric organisation results in asymmetries in the interaction strengths, which reduces instability by keeping the weight of short (positive) and longer (positive and negative) feedback loops low. Our results support the idea that interference competition leads to instability and exclusion but demonstrate that this is not because of, but despite, competitive hierarchy.
Complex European invasion history of Anoplophora glabripennis (Motschulsky): new insights in its population genomic differentiation using genotype-by-sequencing
(2024) Haeussermann, Iris; Hasselmann, Martin; Haeussermann, Iris; Institute of Animal Science, Department of Livestock Population Genomics, Centre for Biodiversity and Integrative Taxonomy (KomBioTa), University of Hohenheim, Stuttgart, Germany; Hasselmann, Martin; Institute of Animal Science, Department of Livestock Population Genomics, Centre for Biodiversity and Integrative Taxonomy (KomBioTa), University of Hohenheim, Stuttgart, Germany
Anthropogenic activities like trade facilitate increasing rates of biological invasions. Asian long-horned beetle (ALB), which is naturally distributed in eastern Asia (China, Korean peninsula), was introduced via wood packing materials (WPM) used in trade to North America (1996) and Europe (2001). We used 7810 single nucleotide polymorphisms (SNPs) derived by a genotype-by-sequencing (GBS) approach to decipher the introduction patterns into Europe. This is applied for the first time on European ALB outbreaks from Germany, Switzerland, and Italy, both from still active and already eradicated infestations. The genome-wide SNPs detected signs of small and highly structured populations within Europe, showing clear founder effects. The very high population differentiation is presumably derived from multiple independent introductions to Europe, which are spatially restricted in mating. By admixture and phylogenetic analyses, some cases of secondary dispersal were observed. Furthermore, some populations suggest admixture, which might have been originated by either multiple introductions from different sources into the new sites or recurrent introductions from an admixed source population. Our results confirmed a complex invasion history of the ALB into Europe and the usability of GBS obtained SNPs in invasion science even without source populations.
Crop cultivation in the Talayotic settlement of Son Fornés (Mallorca, Spain): agricultural practices on the western Mediterranean islands in the first millennium bce
(2024) Stika, Hans-Peter; Neugebauer, Aleta; Rihuete-Herrada, Cristina; Risch, Roberto; Micó, Rafael; Voltas, Jordi; Amengual, Paula; Gelabert, Lara; Lull, Vicente
The Balearic Islands were colonised around the transition from the Chalcolithic to the Bronze Age, not earlier than 2300 cal bce and certainly much later than any central or eastern Mediterranean islands. The number of archaeobotanical records is low and consists mainly of cereals and a few pulses. We present here new results of our long-term study of Son Fornés, an archaeological site on Mallorca which was occupied since the beginning of the Iron Age Talayotic period (~ 850 cal bce ) and until Roman times (123 bce onwards), in the Balearic Islands. In the Talayotic period of Son Fornés Hordeum vulgare var. vulgare (hulled barley) and Triticum aestivum/durum/turgidum (free-threshing wheat) were the main cereals grown and Vicia faba (broad bean) was the main pulse, while Avena sp. (oats) is considered to have been a weed but was nonetheless consumed and was probably in an early phase of being domesticated. For the subsequent post-Talayotic (ca. 550 − 250 bce ), Classic I and Classic II, the Republican Roman occupation period (from 123 bce onwards) the databases are weak, displaying hulled barley as the main crop and broad bean as the main pulse. The archaeobotanical records of Ficus carica (fig), Olea europaea (olive) and Vitis vinifera (grapevine) represent wild or cultivated and domesticated forms. Prunus dulcis (almond) and Pinus pinea (stone pine) were found on Eivissa (Ibiza), pointing to a Phoenician introduction to the islands, while Phoenix dactylifera (date palm) and Castanea sativa (chestnut), found on Menorca, might have been brought in by the Romans. The number of crops being used on the Balearic Islands was limited when compared to sites of similar periods on the European mainland or the central and eastern Mediterranean islands. According to carbon isotope results of Δ 13 C, hulled barley grew under damper conditions than free-threshing wheat. The high δ 15 N values indicated that both crops were well-manured with animal dung during the entire occupation period.
Decoding the geography of natural TBEV microfoci in German: a geostatistical approach based on land-use patterns and climatological conditions
(2022) Borde, Johannes P.; Glaser, Rüdiger; Braun, Klaus; Riach, Nils; Hologa, Rafael; Kaier, Klaus; Chitimia-Dobler, Lidia; Dobler, Gerhard
Background: Tickborne-encephalitis (TBE) is a potentially life-threating neurological disease that is mainly transmitted by ticks. The goal of the present study is to analyze the potential uniform environmental patterns of the identified TBEV microfoci in Germany. The results are used to calculate probabilities for the present distribution of TBEV microfoci in Germany based on a geostatistical model. Methods: We aim to consider the specification of environmental characteristics of locations of TBEV microfoci detected in Germany using open access epidemiological, geographical and climatological data sources. We use a two-step geostatistical approach, where in a first step, the characteristics of a broad set of environmental variables between the 56 TBEV microfoci and a control or comparator set of 3575 sampling points covering Germany are compared using Fisher’s Exact Test. In the second step, we select the most important variables, which are then used in a MaxEnt distribution model to calculate a high resolution (400 × 400 m) probability map for the presence of TBEV covering the entire area of Germany. Results: The findings from the MaxEnt prediction model indicate that multi annual actual evapotranspiration (27.0%) and multi annual hot days (22.5%) have the highest contribution to our model. These two variables are followed by four additional variables with a lower, but still important, explanatory influence: Land cover classes (19.6%), multi annual minimum air temperature (14.9%), multi annual sunshine duration (9.0%), and distance to coniferous and mixed forest border (7.0%). Conclusions: Our findings are based on defined TBEV microfoci with known histories of infection and the repeated confirmation of the virus in the last years, resulting in an in-depth high-resolution model/map of TBEV microfoci in Germany. Multi annual actual evapotranspiration (27%) and multi annual hot days (22.5%) have the most explanatory power in our model. The results may be used to tailor specific regional preventive measures and investigations.
Disc mower versus bar mower: Evaluation of the direct effects of two common mowing techniques on the grassland arthropod fauna
(2025) von Berg, Lea; Frank, Jonas; Betz, Oliver; Steidle, Johannes L. M.; Böttinger, Stefan; Sann, Manuela
1. In Central Europe, species‐rich grasslands are threatened by intensive agriculture with frequent mowing, contributing to the reduction of arthropods such as insects and spiders. However, comprehensive and standardised studies on the direct effects of the two most agriculturally relevant mowing techniques, e.g., double‐blade bar mower versus disc mower, are lacking. 2. In a 2‐year experiment, we have investigated the direct effect of mowing on eight abundant arthropod groups in grassland, covering two seasonal mowing events in both years, using a randomised block design. We compared (a) an unmown control, (b) a double‐blade bar mower and (c) a disc mower. 3. For most of the taxonomic groups studied, a significantly lower number of individuals was found in the experimental plots immediately after mowing, regardless of the mowing technique, compared to an unmown control. This was not the case for Orthoptera and Coleoptera, which did not show a significant reduction in the number of individuals for both mowing techniques (Orthoptera) or only for the double‐blade bar mower (Coleoptera). 4. Between both mowing techniques, no significant differences were found for all taxonomic groups investigated. 5. Synthesis and applications: Our findings suggest that mowing in general has a negative impact on abundant arthropod groups in grassland, regardless of the method used. Tractor‐driven double‐blade bar mowers do not seem to be a truly insect‐friendly alternative to a conventional disc mower. Other factors such as cutting height and mowing regimes should be seriously considered to protect spiders and insects from the negative effects of mowing. In addition, we strongly recommend the maintenance of unmown refugia. Insects and spiders that are spared by mowing can take refuge in these unmown areas to avoid subsequent harvesting and thermally unfavourable conditions that arise on mown areas. Further, unmown refugia are basic habitat structures for a subsequent recolonisation of mown areas once the flora has recovered.
Echinococcus multilocularis and other taeniid metacestodes of muskrats in Luxembourg: prevalence, risk factors, parasite reproduction, and genetic diversity
(2022) Martini, Matilde; Dumendiak, Sonja; Gagliardo, Anna; Ragazzini, Francesco; La Rosa, Letizia; Giunchi, Dimitri; Thielen, Frank; Romig, Thomas; Massolo, Alessandro; Wassermann, Marion
Muskrats (Ondatra zibethicus) are competent intermediate hosts for Echinococcus multilocularis, are frequently infected with this zoonotic cestode, and have even been proposed as a target species to monitor endemicity levels of this parasite. However, their contribution to maintaining the parasitic lifecycle is still unclear. To obtain data on infection frequency and reproductive potential, 280 muskrats from the Grand Duchy of Luxembourg were examined for cestode larvae in the years 2013–2017. Based on morphological and molecular identification, Echinococcus multilocularis was found at a prevalence of 14.6%. Other metacestodes were Hydatigera kamiyai, with a prevalence of 45.7%, Taenia martis with 8.9%, Taenia polyacantha with 5.0%, and Versteria mustelae, which was found in 0.7% of all muskrats. More than 80% of E. multilocularis-infected muskrats contained fertile metacestodes with a mean number of >300,000 (and up to 1,609,816) protoscoleces, which is by far the highest reproductive potential known from any intermediate host species in Europe. Temporal analysis of E. multilocularis prevalence within the study period (and in comparison with earlier data) strongly indicates a robust increase in the studied area. Host age seemed to be an important risk factor for infection, as well as co-infections with Hydatigera kamiyai. A preference for the right medial lobe of the liver as the location of E. multilocularis metacestode was observed. Intraspecific genetic variation among 89 discrete E. multilocularis metacestodes was non-existent based on 300–1590 bp sections of cox1. This is a stark contrast to H. kamiyai, of which nine haplotypes were found on a short 318 bp section of cox1, resulting in genetic diversity in the small country of Luxembourg at a similar level than previously reported from large stretches of Europe and northern Asia.
Echinococcus multilocularis and other zoonotic helminths in red foxes (Vulpes vulpes) from a southern German hotspot for human alveolar echinococcosis
(2023) Schneider, Carina; Kratzer, Wolfgang; Binzberger, Andreas; Schlingeloff, Patrycja; Baumann, Sven; Romig, Thomas; Schmidberger, Julian
Background: We describe the spatial distribution of Echinococcus multilocularis in its main definitive host, the red fox, and the distribution of human cases of alveolar echinococcosis (AE) within a highly endemic focus in southern Germany (13.7–19.9/100,000 in 1992–2018). Human cases were unequally distributed within the endemicity focus. The purpose of the study was to test whether this is reflected in the small-scale distribution of E. multilocularis in foxes. Methods: Three areas with contrasting numbers of human cases were selected within the counties of Ravensburg and Alb-Donau, Baden-Württemberg, Germany. From 2018 to 2020, a total of 240 fox carcasses were obtained from traditional hunters in these areas. Carcasses were necropsied and examined for the presence of intestinal helminths. The statistical analysis was performed with SAS version 9.4, and the geo-mapping with QGIS version 3.16.0 Hannover. Results: The prevalence of E. multilocularis in foxes was 44/106 (41.5%) in area I (commune Leutkirch and environs), 30/59 (50.8%) in area II (commune Isny and environs), and 31/75 (41.3%) in area III (commune Ehingen and environs). From 1992 to 2018, a total of nine human cases of alveolar echinococcosis were recorded in area I, five cases were recorded in study area III, and no cases were recorded in area II. No statistically significant differences between the areas were observed ( P > 0.05) for intestinal infections with E. multilocularis , and no apparent spatial correlation with the small-scale distribution of human cases was found. Concerning other zoonotic helminths, Toxocara spp. were equally common, with prevalence of 38.7%, 47.4% and 48.0%, respectively, while the frequency of Alaria alata varied among the study areas (0.0–9.4%), probably reflecting the specific habitat requirements for the establishment of its complex life cycle. Conclusions: Echinococcus multilocularis is highly prevalent in foxes in all the studied areas. The varying number of human AE cases within these areas should therefore be caused by factors other than the intensity of parasite transmission in foxes.
The emergence of ecotypes in a parasitoid wasp: a case of incipient sympatric speciation in Hymenoptera?
(2021) Malec, Pawel; Weber, Justus; Böhmer, Robin; Fiebig, Marc; Meinert, Denise; Rein, Carolin; Reinisch, Ronja; Henrich, Maik; Polyvas, Viktoria; Pollmann, Marie; von Berg, Lea; König, Christian; Steidle, Johannes L. M.
Background: To understand which reproductive barriers initiate speciation is a major question in evolutionary research. Despite their high species numbers and specific biology, there are only few studies on speciation in Hymenoptera. This study aims to identify very early reproductive barriers in a local, sympatric population of Nasonia vitripennis (Walker 1836), a hymenopterous parasitoid of fly pupae. We studied ecological barriers, sexual barriers, and the reduction in F1-female offspring as a postmating barrier, as well as the population structure using microsatellites. Results: We found considerable inbreeding within female strains and a population structure with either three or five subpopulation clusters defined by microsatellites. In addition, there are two ecotypes, one parasitizing fly pupae in bird nests and the other on carrion. The nest ecotype is mainly formed from one of the microsatellite clusters, the two or four remaining microsatellite clusters form the carrion ecotype. There was slight sexual isolation and a reduction in F1-female offspring between inbreeding strains from the same microsatellite clusters and the same ecotypes. Strains from different microsatellite clusters are separated by a reduction in F1-female offspring. Ecotypes are separated only by ecological barriers. Conclusions: This is the first demonstration of very early reproductive barriers within a sympatric population of Hymenoptera. It demonstrates that sexual and premating barriers can precede ecological separation. This indicates the complexity of ecotype formation and highlights the general need for more studies within homogenous populations for the identification of the earliest barriers in the speciation process.
Evolutionary genomics of socially polymorphic populations of Pogonomyrmex californicus
(2024) Errbii, Mohammed; Ernst, Ulrich R.; Lajmi, Aparna; Privman, Eyal; Gadau, Jürgen; Schrader, Lukas; Errbii, Mohammed; Molecular Evolution and Sociobiology Group, Institute for Evolution and Biodiversity, University of Münster, Hüfferstr. 1, DE-48149, Münster, Germany; Ernst, Ulrich R.; Molecular Evolution and Sociobiology Group, Institute for Evolution and Biodiversity, University of Münster, Hüfferstr. 1, DE-48149, Münster, Germany; Lajmi, Aparna; Department of Evolutionary and Environmental Biology, Institute of Evolution, University of Haifa, Haifa, Israel; Privman, Eyal; Department of Evolutionary and Environmental Biology, Institute of Evolution, University of Haifa, Haifa, Israel; Gadau, Jürgen; Molecular Evolution and Sociobiology Group, Institute for Evolution and Biodiversity, University of Münster, Hüfferstr. 1, DE-48149, Münster, Germany; Schrader, Lukas; Molecular Evolution and Sociobiology Group, Institute for Evolution and Biodiversity, University of Münster, Hüfferstr. 1, DE-48149, Münster, Germany
Background: Social insects vary considerably in their social organization both between and within species. In the California harvester ant, Pogonomyrmex californicus (Buckley 1867), colonies are commonly founded and headed by a single queen (haplometrosis, primary monogyny). However, in some populations in California (USA), unrelated queens cooperate not only during founding (pleometrosis) but also throughout the life of the colony (primary polygyny). The genetic architecture and evolutionary dynamics of this complex social niche polymorphism (haplometrosis vs pleometrosis) have remained unknown. Results: We provide a first analysis of its genomic basis and evolutionary history using population genomics comparing individuals from a haplometrotic population to those from a pleometrotic population. We discovered a recently evolved (< 200 k years), 8-Mb non-recombining region segregating with the observed social niche polymorphism. This region shares several characteristics with supergenes underlying social polymorphisms in other socially polymorphic ant species. However, we also find remarkable differences from previously described social supergenes. Particularly, four additional genomic regions not in linkage with the supergene show signatures of a selective sweep in the pleometrotic population. Within these regions, we find for example genes crucial for epigenetic regulation via histone modification (chameau) and DNA methylation (Dnmt1). Conclusions: Altogether, our results suggest that social morph in this species is a polygenic trait involving a potential young supergene. Further studies targeting haplo- and pleometrotic individuals from a single population are however required to conclusively resolve whether these genetic differences underlie the alternative social phenotypes or have emerged through genetic drift.
Hitze als Schlüssel zur Aufklärung der Lysogenie beim SPß-Phagen
(2025) Kohm, Katharina
Integrative description of Temnothorax siculus sp. n.: a new ant species from Sicily, Italy (Hymenoptera, Formicidae)
(2025) Schifani, Enrico; Alicata, Antonio; Prebus, Matthew M.; Csősz, Sándor; Fernández, Fernando; Guerrero, Roberto José
The mostly Holarctic genus Temnothorax (Hymenoptera, Formicidae) is the most diverse ant genus in temperate regions. The Mediterranean, a biodiversity hotspot of rare ant species, hosts over 150 Temnothorax taxa, including several short-range endemics. Over the last few years, phylogenomic reconstructions and integrative taxonomy have significantly improved the understanding of global Temnothorax diversity, but much taxonomic work is still needed in the Mediterranean region. Here, we present the integrative description of a new species of the genus, discovered in the central Mediterranean island of Sicily: Temnothorax siculus sp. n. is defined and compared to congeneric species integrating morphometrics and phylogenomics. It is a ground-nesting, lowland species, of which workers were regularly observed foraging on bushes and small trees. In the global phylogeny, covering all the main lineages of the region, it belongs to the Palearctic clade and is related to the tuberum and unifasciatus complexes. Morphological separation from other Sicilian Temnothorax species can generally be achieved on qualitative characters, but we also provide morphometric discriminant functions to separate it from T. apenninicus and especially T. unifasciatus . Temnothorax siculus has been rarely collected but appears to be widespread in Sicily, and may occur in neighboring regions.
Inter-laboratory comparison of plant volatile analyses in the light of intra-specific chemodiversity
(2023) Eckert, Silvia; Eilers, Elisabeth J.; Jakobs, Ruth; Anaia, Redouan Adam; Aragam, Kruthika Sen; Bloss, Tanja; Popp, Moritz; Sasidharan, Rohit; Schnitzler, Jörg-Peter; Stein, Florian; Steppuhn, Anke; Unsicker, Sybille B.; van Dam, Nicole M.; Yepes, Sol; Ziaja, Dominik; Müller, Caroline
Introduction: Assessing intraspecific variation in plant volatile organic compounds (VOCs) involves pitfalls that may bias biological interpretation, particularly when several laboratories collaborate on joint projects. Comparative, inter-laboratory ring trials can inform on the reproducibility of such analyses. Objectives: In a ring trial involving five laboratories, we investigated the reproducibility of VOC collections with polydimethylsiloxane (PDMS) and analyses by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). As model plant we used Tanacetum vulgare , which shows a remarkable diversity in terpenoids, forming so-called chemotypes. We performed our ring-trial with two chemotypes to examine the sources of technical variation in plant VOC measurements during pre-analytical, analytical, and post-analytical steps. Methods: Monoclonal root cuttings were generated in one laboratory and distributed to five laboratories, in which plants were grown under laboratory-specific conditions. VOCs were collected on PDMS tubes from all plants before and after a jasmonic acid (JA) treatment. Thereafter, each laboratory (donors) sent a subset of tubes to four of the other laboratories (recipients), which performed TD-GC-MS with their own established procedures. Results: Chemotype-specific differences in VOC profiles were detected but with an overall high variation both across donor and recipient laboratories. JA-induced changes in VOC profiles were not reproducible. Laboratory-specific growth conditions led to phenotypic variation that affected the resulting VOC profiles. Conclusion: Our ring trial shows that despite large efforts to standardise each VOC measurement step, the outcomes differed both qualitatively and quantitatively. Our results reveal sources of variation in plant VOC research and may help to avoid systematic errors in similar experiments.
Das Land‐Atmosphäre‐System der Erde: die „Erdung“ von Wetter‐ und Klimaprozessen
(2025) Wulfmeyer, Volker; Jach, Lisa; Branch, Oliver; Breil, Marcus
Das System Land-Atmosphäre umfasst den Boden, die Landbedeckung und die untere Troposphäre. Die komplexen Prozesse in diesem System sind gekoppelt über den Austausch von Impuls, Energie und Masse. Unter anderem spielt der Pflanzenbewuchs eine zentrale Rolle. Daher ist ein tiefgreifendes Verständnis dieses Systems fundamental für die Genauigkeit von Wettervorhersagen, mittelfristige bis subsaisonale Vorhersagen und Klimaprognosen. Dazu gehört auch die Vorhersage von Extremereignissen wie Dürren.
The low mutational flexibility of the EPSP synthase in Bacillus subtilis is due to a higher demand for shikimate pathway intermediates
(2023) Schwedt, Inge; Schöne, Kerstin; Eckert, Maike; Pizzinato, Manon; Winkler, Laura; Knotkova, Barbora; Richts, Björn; Hau, Jann-Louis; Steuber, Julia; Mireles, Raul; Noda‐Garcia, Lianet; Fritz, Günter; Mittelstädt, Carolin; Hertel, Robert; Commichau, Fabian M.
Glyphosate (GS) inhibits the 5-enolpyruvyl-shikimate-3-phosphate (EPSP) synthase that is required for aromatic amino acid, folate and quinone biosynthesis in Bacillus subtilis and Escherichia coli. The inhibition of the EPSP synthase by GS depletes the cell of these metabolites, resulting in cell death. Here, we show that like the laboratory B. subtilis strains also environmental and undomesticated isolates adapt to GS by reducing herbicide uptake. Although B. subtilis possesses a GS-insensitive EPSP synthase, the enzyme is strongly inhibited by GS in the native environment. Moreover, the B. subtilis EPSP synthase mutant was only viable in rich medium containing menaquinone, indicating that the bacteria require a catalytically efficient EPSP synthase under nutrient-poor conditions. The dependency of B. subtilis on the EPSP synthase probably limits its evolvability. In contrast, E. coli rapidly acquires GS resistance by target modification. However, the evolution of a GS-resistant EPSP synthase under non-selective growth conditions indicates that GS resistance causes fitness costs. Therefore, in both model organisms, the proper function of the EPSP synthase is critical for the cellular viability. This study also revealed that the uptake systems for folate precursors, phenylalanine and tyrosine need to be identified and characterized in B. subtilis.
Market-based instruments for biodiversity in agricultural landscapes: An evaluation of quality criteria in a German case study
(2025) Streit, Lea; Feuerbacher, Arndt; Röhl, Markus
Market-based instruments (MBIs) for the protection and promotion of biodiversity have gained significant importance in recent years. The success of MBIs depends largely on the transparent presentation of their actual effects, which rely on the quality of implementation. Quality criteria can be used to evaluate this. To date, few studies have examined whether and how these criteria are applied. This study seeks to address this gap, by using MBIs in the German agricultural landscape as a case study. Quality criteria were defined on the basis of a literature review; then applied to MBIs identified through an internet search and finally analyzed. Quality criteria related to methodological approaches (implementation, maintenance, used seed mixtures) and quality control (monitoring, localization) are presented less frequently than information on rights and obligations or the use of financial funds. Among the 151 MBIs analyzed, 70% lack control mechanisms and monitoring systems, indicating unverified effectiveness. Additionally, MBIs financed through program approaches are more likely to have control mechanisms and include perennial measures than MBIs funded by direct payments of sponsors or consumers purchasing a product. The development of MBI offerings suggests that there is persistent and growing demand, as some programs have been running for several decades. However, without ecological monitoring, it is not possible to ascertain whether these measures benefit biodiversity. To establish standardized methods for comparing MBIs for biodiversity, policymakers must consider official guidelines and, where appropriate, implement regulatory frameworks.
Monomorium dine sp. nov. (Hymenoptera, Formicidae): a new inquiline social parasite ant species from North America
(2025) Cover, Stefan P.; Rabeling, Christian
Among the very rarest of Nearctic ants are three species of inquiline social parasites belonging to the genus Monomorium, namely Monomorium inquilinum DuBois, Monomorium pergandei (Emery), and Monomorium talbotae DuBois. All three species are known only from the type collections. Here, we describe Monomorium dine Cover & Rabeling, sp. nov., from the Navajo Nation in New Mexico, USA, a new species closely similar to the three known social parasites. Like them, M. dine appears to be a workerless inquiline that exploits a free-living Monomorium host. We also provide keys to the queens of the Nearctic Monomorium inquilines, provide the first images of these species, report new collections for Monomorium talbotae DuBois, discuss host-parasite associations, and summarize what is presently known about these mysterious social parasites.
Morphological and molecular identification of sarcocystis arctica in captive cheetahs (Acinonyx jubatus) in China helps clarify phylogenetic relationships with Sarcocystis caninum and Sarcocystis felis
(2025) Liao, Zhe; Zhu, Niuping; Yang, Yurong; Deng, Shuangsheng; Jäkel, Thomas; Hu, Junjie; Salvarani, Felipe M.; Domingues, Sheyla Farhayldes Souza; Da Silveira, Júlia Angélica Gonçalves
To date, only one case is known where protozoan parasites of the genus Sarcocystis were found to infect cheetahs ( Acinonyx jubatus ); the cysts in the musculature were morphologically identified as S. felis . Here, we characterized sarcocysts by morphological and molecular methods that were observed in cheetahs who died in zoos in China. Only one type of sarcocyst was present in two of six cheetahs. By light microscopy, the sarcocyst wall was striated, 1.4–2.1 μm thick. Ultrastructurally, the wall had irregular-shaped, small villar protrusions, resembling wall type 9c, similar to those of S. arctica , S. caninum , and S. felis . The samples shared their highest molecular identity values with those of S. arctica and S. caninum : 99.9–100% and 99.8–100% (18S rRNA), 99.5% and 99.3–99.5% (28S rRNA), 95.9–97.5% and 96.3–97.3% (ITS-1), and 99.6% and 99.2–99.7% ( cox 1), respectively. Compared with ITS-1 of S. felis , identities ranged between 87.5% and 88.9%. Phylogenetic reconstruction revealed that the newly sequenced Sarcocystis clustered with S. arctica and S. caninum , whereas S. felis (ITS-1) and S. canis (ITS-1, 18S rRNA, cox 1) were sister species. Thus, we addressed the Sarcocystis species from the cheetahs as S. arctica , which is the first record of a Sarcocystis species believed to be specific for canids as intermediate hosts to infect a feline host.
Nutritional potential of underutilized edible plant species in coffee agroforestry systems of Yayu, southwestern Ethiopia
(2021) Aragaw, Habtamu Seyoum; Nohr, Donatus; Callo-Concha, Daniel
Ethiopia is confronted with the paradox of hosting hundreds of edible plants and having high food and nutritional insecurity. Meals are mainly made up of staples and often lack of protein and micronutrients. Therefore, a large section of the population, particularly children and women, are malnourished. We hypothesize that wild edible plant species can contribute to fulfil the micronutrient demands of local people. Hence, we assessed the nutritional potential of underutilized edible plant species growing in understories of coffee agroforestry systems of southwestern Ethiopia. An ethnobotanical household survey (n = 300) documented the edible existing plants; and a promising subset of them (n = 12) was analysed for nutrient and antinutritional factor content in the lab. All 12 species, except fruits, have higher calcium, iron and zinc contents compared to regularly cultivated crops. Vitamin C was high in Syzygium guineense (330.72 mg/100 g edible parts or EP) and Rubus apetalus (294.19 mg/100 g). Beta-carotene ranged from 9.2 to 75 µg retinol activity equivalent (RAE) /100 g 25 among all species, but was exceptionally high in Rubus apetalus (161.7 µg RAE/100 g). Concerning the antinutritional factors, phytate content varied from 31.06 to 601.65 µg/100 g, being lower in Dioscorea prehensilis (31.06 µg/100 g) and D. alata (90.17 µg/100 g) compared to Carissa spinarum (601.65 µg/100 g) and Solanum nigrum (536.48 µg/100 g). Thus, we conclude that the assessed underutilized species are potential sources of dietary nutrients locally needed, and are notable Amaranthus graecizans, Portulaca oleracea and Dioscorea cayenensis as providers of Ca, Fe and Zn, and the fruit Rubus apetalus of provitamin A.
The potential of farnesene isomer mixtures to support the control of aphids in the cultivation of lettuce crops
(2025) Kuhn, Denise; Bauer, Philipp; Tolasch, Till; Petschenka, Georg; Steidle, Johannes L. M.; Kuhn, Denise; Department of Chemical Ecology 190 T, Institute of Biology, University of Hohenheim, 70599, Stuttgart, Germany; Bauer, Philipp; Department of Applied Entomology 360 C, Institute of Phytomedicine, University of Hohenheim, 70599, Stuttgart, Germany; Tolasch, Till; Department of Chemical Ecology 190 T, Institute of Biology, University of Hohenheim, 70599, Stuttgart, Germany; Petschenka, Georg; Department of Applied Entomology 360 C, Institute of Phytomedicine, University of Hohenheim, 70599, Stuttgart, Germany; Steidle, Johannes L. M.; Department of Chemical Ecology 190 T, Institute of Biology, University of Hohenheim, 70599, Stuttgart, Germany
(E)-ß-farnesene (EBF) acts as an alarm pheromone of many aphid species and is also used as an aphid repellent by plants. Upon perception of EBF, aphids exhibit avoidance behavior. They walk away, stop feeding or drop from leaves. Moreover, EBF is an attractant for natural enemies of aphids. However, EBF is not used in pest management because it is expensive in its pure form. Therefore, we assessed the effect of a less expensive farnesene isomer mixture (FIM) on Myzus persicae (Sternorrhyncha: Aphidiae) on lettuce ( Lactuca sativa var. Ulmo) in the laboratory and under field conditions. First, we tested under laboratory conditions if FIM has the same effect on M. persicae as it is described for pure EBF. The aphids were influenced by EBF. They stopped feeding, withdrew their stylets, went away from the danger zone, or developed and reproduced more slowly. Therefore, we studied the behavioral response of the aphids after FIM application and aphid reproduction under permanent exposure of FIM. Second, we tested in the field the reaction to FIM either directly applied to lettuce or released by dispensers. In the lab experiments, we found that M. persicae reacts to FIM by walking away and that reproduction tends to be reduced in the presence of FIM. In the field, we found lower numbers of aphids in the treatments with FIM. In particular, dispenser application caused higher aphid reduction compared to spray application on lettuce. In addition, more natural enemies of aphids could be found in dispenser-treated plots. Taken together, these results indicate that the use of FIM could contribute to insecticide-free aphid control in lettuce, but possibly also in other crops.

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