A decrease among honey bee populations (Apis mellifera) in the traditional apiaries has been observed in recent years. In light of this negative phenomenon, urban beekeeping seems to be an appropriate alternative solution for the bee population in reducing the toxic effects of a large number of pesticides that are commonly used in agricultural ecosystems. Despite the rapid development of urban beekeeping, there is little information regarding the different aspects of the defense effectiveness of bees from the urban and rural areas. The study was aimed to show whether honey bees from these two locations differ in the level of the valuable biomarkers of stress exposure helpful in establishing which bees, from urban or rural areas, are under greater environmental pressure. For this purpose, foragers from an urban rooftop apiary and a traditional rural apiary were collected. The chosen biomarkers were measured in various tissues of bees. The activity of glutathione S-transferase and acetylcholinesterase, the level of total antioxidant capacity, heat shock protein 70 (Hsp70), and defensin were selected for the analyses. In our opinion, the Hsp70 and defensin levels seemed to be important in the indication of urban multistress factors. The higher level of heat shock proteins and defensins in tissues/organs of bees from the urban apiary—in the gut (an increase, respectively, 92% and 7.3%) and fat body (an increase, respectively, 130% and 7.8%), known as targets of environmental toxins, pointed out the urban environment as highly stressful at both the individual and colony levels. In turn, high total antioxidant capacity was measured in the guts of honey bees from rural area (an increase 107%). Such a situation suggests a different mechanism of defense and specificity of rural and urban environmental stressors and also honey bees foraging activity.

Honey is a source of natural antioxidant compounds exerting several health-beneficial effects. Since urban beekeeping is quite common, the fear among potential consumers about the quality and the safety of honey produced exclusively in the cities is observed. However, the antioxidant properties of urban honey have not yet been tested. We described the antioxidant properties of linden honey from urban and rural areas. We analyzed the total phenolic content, DPPH• radical scavenging activity, Trolox equivalent antioxidant activity assay, the protein content, and catalase activity. The analysis showed that all tested parameters were significantly higher in honey from rural areas than in urban samples. The differences in the obtained results are certainly not the effect of the floral composition of honey, but rather due to the location of the honeybee colonies. It seems that the consumption of honey from urban areas for health purposes should be considered.

Background Knowledge about vitellogenesis in spiders is rudimentary. Therefore, the aim of study was to check the vitellogenin (Vg) presence in various tissues of the female spider Parasteatoda tepidariorum , determine when and where vitellogenesis starts and takes place, and the putative role of selected hormones in the vitellogenesis. Results Here we show two genes encoding Vg (Pt Vg 4 and Pt Vg 6) in the genome of the spider P. tepidariorum . One gene Pt Vg 4 and three subunits of Vg (250 kDa, 47 kDa and 30 kDa) are expressed in the midgut glands, ovaries and hemolymph . Heterosynthesis of the Vg in the midgut glands and autosynthesis in the ovaries were observed. Vitellogenesis begins in the last nymphal stage in the midgut glands (heterosynthesis). However, after sexual maturity is reached, Vg is also synthesized in the ovaries (autosynthesis). Changes in the Pt Vg 4 expression level and in the Vg concentration after treatment with 20-hydroxyecdysone, a juvenile hormone analog (fenoxycarb) and an antijuvenoid compound (precocene I) were observed. Therefore, we propose a hypothetical model for the hormonal regulation of vitellogenesis in P. tepidariorum . Conclusions Our results are the first comprehensive study on spider vitellogenesis. In our opinion, this work will open discussion on the evolutionary context of possible similarities in the hormonal control of vitellogenesis between P. tepidariorum and other arthropods as well as their consequences.

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Spiders (Araneae) create abundant and diverse assemblages in many agroecosystems, where they play a crucial role as the main group of predators and pest controllers. However, seasonal disturbance in the agricultural environment (e.g., harvesting or ploughing) affects spider assemblages. The main aim of this research was to compare assemblages of Araneae colonising cereal fields cultivated under two different systems of soil tillage: conventional with ploughing and non-inversion tillage. The research covered plantations of triticale, wheat, and barley, situated in northeastern Poland. Ground-dwelling spiders were captured into modified pitfall traps filled up to 1/3 height with an ethylene glycol solution. In total, 6744 spiders representing 67 species classified in 13 families were caught. The traps were emptied every two weeks from the end of April until the end of July. A total of 2410 specimens representing 55 species were captured in the fields with simplified cultivation, while the remaining 4334 specimens representing 49 species were trapped in conventional fields where ploughing was performed. The Shannon diversity (H’) and evenness (J’) indices reached higher values in the fields without ploughing. According to IndVal Erigone, dentipalpis and Bathyphantes gracilis were signifi-cantly characteristic (p < 0.05) for non-inversion soil tillage, whereas six species, Oedothorax apicatus, Pardosa prativaga, Pardosa paludicola, Pachygnatha clerki, Dicimbium nigrum brevisetosum, and Clubiona reclusa, were typical of soil tillage with ploughing. The research showed that simplification of soil tillage in cereal fields improves the biodiversity of arachnofauna in agricultural ecosystems. The use of conventional tillage systems with ploughing promotes agrobiontic species of the families Linyphiidae and Lycosidae.