Limited variation in microbial communities across populations of Macrosteles leafhoppers (Hemiptera: Cicadellidae).

Microbial symbionts play crucial roles in insect biology, yet their diversity, distribution, and temporal dynamics across host populations remain poorly understood. In this study, we investigated the spatio-temporal distribution of bacterial symbionts within the widely distributed and economically significant leafhopper genus Macrosteles, with a focus on Macrosteles laevis. Using host and symbiont marker gene amplicon sequencing, we explored the intricate relationships between these insects and their microbial partners. Our analysis of the cytochrome oxidase subunit I (COI) gene data revealed several intriguing findings. First, there was no strong genetic differentiation across M. laevis populations, suggesting gene flow among them. Second, we observed significant levels of heteroplasmy, indicating the presence of multiple mitochondrial haplotypes within individuals. Third, parasitoid infections were prevalent, highlighting the complex ecological interactions involving leafhoppers. The 16S rRNA data confirmed the universal presence of ancient nutritional endosymbionts-Sulcia and Nasuia-in M. laevis. Additionally, we found a high prevalence of Arsenophonus, another common symbiont. Interestingly, unlike most previously studied species, M. laevis exhibited only occasional cases of infection with known facultative endosymbionts and other bacteria. Notably, there was no significant variation in symbiont prevalence across different populations or among sampling years within the same population. Comparatively, facultative endosymbionts such as Rickettsia, Wolbachia, Cardinium and Lariskella were more common in other Macrosteles species. These findings underscore the importance of considering both host and symbiont dynamics when studying microbial associations. By simultaneously characterizing host and symbiont marker gene amplicons in large insect collections, we gain valuable insights into the intricate interplay between insects and their microbial partners. Understanding these dynamics contributes to our broader comprehension of host-microbe interactions in natural ecosystems.

Environmental impact assessment of dicationic ionic liquids with ammonium-phosphonium cations and amino acid anions.

Progress in the development of biodegradable or biobased ionic liquids (ILs) has led to the design of green compounds for several applications. Herein, four biocompatible dicationic ionic liquids (DILs) with ammonium-phosphonium cations and amino acid anions were synthesized and investigated their environmental impact. The structures of the DILs were confirmed by spectral analyses (1H, 13C and 31P NMR). Furthermore, physicochemical properties such as density, viscosity and refractive index were determined. Water content, bromide content and solubility were thereafter determined as the parameters needed for further studies. Subsequently, their antifeedant activity towards economically important pests of grain in storage warehouses: the granary weevil, the confused flour beetle, and the khapra beetle was examined, showing the dependence on structure. Moreover, selected DILs were investigated for toxicity towards white mustard, Daphnia magna, and Artemia franciscana to specify the environmental impact. These studies were complemented by understand the biodegradation of DILs by bacterial communities derived from soil at the agricultural land. The result was DILs with limited environmental footprints that have great potential for further application studies.

Body Remains Left by Bird Predators as a Reliable Source for Population Genetic Studies in the Great Capricorn Beetle Cerambyx cerdo, a Veteran Oak Specialist.

Obtaining biological material for DNA extraction is often challenging in organisms of conservation interest. Non-invasive sampling (i.e., sampling without injuring or disturbing an animal) is preferred as it carries no risk to the population's survival. Here, we tested the possibility of using the body remains left by bird predators for microsatellite genotyping in Cerambyx cerdo, a veteran oak specialist. We compared results obtained from such potentially degraded samples with samples of fresh beetle tarsi (i.e., invasive and destructive but non-lethal samples). Using 10 SSR loci, we genotyped 28 fresh, and 28 remains samples. The analysis indicated that PCR amplification efficiency was not influenced by sample type but allele length and individual heterozygosity. Allele frequencies were perfectly correlated for both sample types (R2 = 0.94). Additionally, null allele frequencies and genotyping failure rates were not significantly different from zero. Although the point estimates of individual inbreeding rates (fi) were higher in remains than fresh samples (medians 0.08 vs. 0.02, respectively), both groups were not significantly different from each other and zero. Our study demonstrated that non-invasive remains samples could provide satisfactory data for population-genetic studies. However, we highlight the problem of biased inbreeding estimates, which may result from samples affected by allelic dropout.

First record of a highly melanic morph of Cyphostethus tristriatus (Fabricius, 1787) (Hemiptera: Heteroptera: Acanthosomatidae).

The term 'melanism' means the occurrence of variant(s) that is/are mostly or completely dark in pigmentation either as intraspecific polymorphisms or as fixed differences between closely related species. Melanism can refer to variation involving discrete melanic and non-melanic phenotypes (melanic and typical morphs) or to cases of continuously varying pigmentation (True 2003). Melanism of moths inhabiting areas with industrial pollution is a very well-known example involving melanic polymorphisms in insects. However, melanism is also known in other insect orders, e.g. Coleoptera and Diptera (Majerus 1998, True 2003).

Third-generation ionic liquids with N-alkylated 1,4-diazabicyclo[2.2.2]octane cations and pelargonate anions.

Ionic liquids that belong to the third-generation designs due to their intended biological activity are compounds with high potential applications as plant-protection products. The present study describes the synthesis and characterization of novel ionic liquids with cations based on the alkyl derivatives of 1,4-diazabicyclo[2.2.2]octane (DABCO) and an anion derived from naturally occurring pelargonic acid. The developed synthesis method allowed obtaining products with a high yield (≥96%), and the liquids were characterized as high-viscosity liquids at room temperature. This allowed classifying the products as ionic liquids (ILs). The structures of the obtained ILs were confirmed on the basis of their NMR and IR spectra as well as by elemental analysis. All the products exhibited surface activity and were capable of partially wetting a hydrophobic surface. The tested ionic liquids exhibited higher herbicidal activity against winter oilseed rape (Brassica napus L.) and common lambsquarters (Chenopodium album L.) at a lower dose compared to a commercial preparation in greenhouse studies. The studied ionic liquids also exhibited different effects as antifeedants on various insect species. The best results were obtained against beetles belonging to the granary weevil species (Sitophilus granarius L.). The relation between the surface-tension-reduction efficiency pC20 and biological activity was investigated. The herbicidal activity was also correlated with the value of the contact angles for the studied pelargonates. All the obtained results indicate that the designed and synthesized ionic liquids possess double biological functions: herbicidal activity and deterrent activity.

Dicationic ionic liquids as new feeding deterrents.

ABSTRACT: In this study, new quaternary bis(ammonium) salts with alkyl-1,X-bis(dimethyldecylammonium) cation and saccharinate, acesulfamate, lactate and pyroglutamate anions were synthesized and characterized by 1H and 13C NMR spectroscopy. Thermal gravimetric and differential scanning calorimetry analyses confirmed that all salts were thermally stable and the majority of them exhibited melting points below 100 °C. The physicochemical properties (viscosity, density, refractive index values, and solubility) of the obtained salts were determined for three compounds with lactate anions. All the tested salts have suitable properties which, in practical application, will reduce the losses caused by the most important storage insects. Most of the synthesized ionic liquids had comparable or better deterrent activity than azadirachtin-an alkaloid known as the most active antifeedant.

Ammonium bio-ionic liquids based on camelina oil as potential novel agrochemicals.

Third generation bio-ionic liquids (bio-ILs) were synthesized based on cheap and increasingly available camelina oil. The ionic liquids were obtained with high yield based on the reaction between camelina oil, which contained the following carboxylic acids: C18:3ω-3 linolenic >30%, C20:1 eicosenoic 28%, C18:2ω-6 linoleic 13%, C18:1 oleic 13%, C16:0 palmitic 4.5%, C22:1 erucic 4.5% and C18:0 stearic 2.5%, and quaternary ammonium hydroxides comprising cations such as: choline, di(hydrogenated tallow)dimethylammonium, oleylmethylbis(2-hydroxyethyl)ammonium, benzalkonium, tetradecyltrimethylammonium, tetramethylammonium and didecyldimethylammonium. The synthesized bio-ILs were characterized as high viscosity liquids which are thermally stable and their solubility in water and organic solvents depended on the type of cation. Two extreme examples of bio-ILs include the water soluble one comprising choline as the cation and the one comprising the di(hydrogenated tallow)dimethylammonium cation, which is soluble in hexane. The presented results show the importance of ammonium bio-ILs as antifeedants with a wide spectrum of activity. The tested beetles (Insecta: Coleoptera) of storage pests: grain weevil (Sitophilus granarius (L.)), confused flour beetle (Tribolium confusum Duv.) and khapra beetle (Trogoderma granarium Ev.) presented notable differences in terms of susceptibility to the synthesized ILs. The synthesized bio-ILs are effective adjuvants for herbicides belonging to the sylfonylurea group. They exhibited high activity despite the fact they were applied at a dose almost half that used for commercial adjuvants, which opens the era of adjuvant ILs. Aside from its use in the production of biodiesel, renewable diesel and renewable jet fuel, camelina oil is starting to become a potential resource for the production of novel agrochemicals.

Lactones 46. Synthesis, antifeedant and antibacterial activity of γ-lactones with a p-methoxyphenyl substituent.

BACKGROUND: Lactones are well known for their biological activity. Grosheimin and repin are potent deterrents against storage pests. The unsaturated lactones have exhibited a wide spectrum of antibacterial activity. In our study we focused on the synthesis and evaluation of the biological activity of anisaldehyde derivatives containing lactone function. RESULTS: Four new lactones were synthesized in one-step reductive dehalogenation or dehydrohalogenation reactions. These compounds, together with halolactones synthesized earlier, were tested for their antifeedant activity towards Sitophilus granaries, Trogoderma granarium and Tribolium confusum. The results of the tests showed that the highest activity, comparable with that of azadirachtin, towards all tested pests (total coefficient of deterrence 143.3-183.9) was observed for lactone with a vinyl substituent. The antibacterial activity of these compounds was also evaluated. The most potent lactone was active towards gram-positive bacteria strains. CONCLUSIONS: The results of biological tests showed that halogen atom removal significantly increased the antifeedant properties of γ-lactones with a p-methoxyphenyl substituent. Unsaturated lactones are most promising in the context of their possible industrial application as crop protection agents. Further structural modifications of lactones with aromatic rings are needed to find important structural factors increasing the antibacterial activity.