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Pollen microbiomes of solitary bees (Osmia rufa L. syn. O. bicornis) from seed orchards
Abstract The red mason (Osmia rufa L. syn. O. bicornis) is a solitary bee that is commonly used for pollination of fruit crops. Given the declining numbers of pollinators in various environments, the mason bee has not only become an effective insect as an additional pollinator, but sometimes it becomes the main species that is used to increase the yield of crops. Due to easy rearing and not showing aggressiveness towards people. The individual features of the mason bee have made the interest in this species constantly growing. Currently, the wild bees is more important for the forestry and production the seeds. So far, only the honeybee (Apis mellifera mellifera) has been successfully used to work in forest areas, especially with the flowers of Tilia cordata Mill. The rearing of mason bee (Osmia rufa L.) in forest areas is new. The paper presents information on the microbiome of pollen collected from the brood chambers of the solitary bee Osmia rufa L. in various forest biotopes: Tilia cordata Mill, Quercus petraea Liebl. and Prunus avium L. The presence of five groups of bacteria was found in all analyzed pollens were rich in α-Proteabacteria, Actinobacteria and Firmicutes, while β-Proteobacteria and Bacteroides were present in a lower level. Despite the presence of bacteria in the pollen, no increased bee mortality was observed in any of the bee nests of forest biotopes. It was found that the forest environment does not pose a threat to the development of Osmia rufa L. bees.
The Influence of Lead and Acyrthosiphon pisum (Harris) on Generation of Pisum sativum Defense Signaling Molecules and Expression of Genes Involved in Their Biosynthesis
The main aim of this study was to understand the regulation of the biosynthesis of phytohormones as signaling molecules in the defense mechanisms of pea seedlings during the application of abiotic and biotic stress factors. It was important to identify this regulation at the molecular level in Pisum sativum L. seedlings under the influence of various concentrations of lead—i.e., a low concentration increasing plant metabolism, causing a hormetic effect, and a high dose causing a sublethal effect—and during feeding of a phytophagous insect with a piercing-sucking mouthpart—i.e., pea aphid (Acyrthosiphon pisum (Harris)). The aim of the study was to determine the expression level of genes encoding enzymes of the biosynthesis of signaling molecules such as phytohormones—i.e., jasmonates (JA/MeJA), ethylene (ET) and abscisic acid (ABA). Real-time qPCR was applied to analyze the expression of genes encoding enzymes involved in the regulation of the biosynthesis of JA/MeJA (lipoxygenase 1 (LOX1), lipoxygenase 2 (LOX2), 12-oxophytodienoate reductase 1 (OPR1) and jasmonic acid-amido synthetase (JAR1)), ET (1-aminocyclopropane-1-carboxylate synthase 3 (ACS3)) and ABA (9-cis-epoxycarotenoid dioxygenase (NCED) and aldehyde oxidase 1 (AO1)). In response to the abovementioned stress factors—i.e., abiotic and biotic stressors acting independently or simultaneously—the expression of the LOX1, LOX2, OPR1, JAR1, ACS3, NCED and AO1 genes at both sublethal and hormetic doses increased. Particularly high levels of the relative expression of the tested genes in pea seedlings growing at sublethal doses of lead and colonized by A. pisum compared to the control were noticeable. A hormetic dose of lead induced high expression levels of the JAR1, OPR1 and ACS3 genes, especially in leaves. Moreover, an increase in the concentration of phytohormones such as jasmonates (JA and MeJA) and aminococyclopropane-1-carboxylic acid (ACC)-ethylene (ET) precursor was observed. The results of this study indicate that the response of pea seedlings to lead and A. pisum aphid infestation differed greatly at both the gene expression and metabolic levels. The intensity of these defense responses depended on the organ, the metal dose and direct contact of the stress factor with the organ.
In Memoriam: Professor Philippe Jeandet – an outstanding scientist and his legacy in natural product chemistry and bioactivity
Professor Philippe Jeandet was one of the world’s leading biologists and plant biochemists, best known for his research on the chemical structure of natural products and their bioactivity, particularly that of stilbenoids. His scientific interests primarily focused on resveratrol (trans-3,5,4'-trihydroxystilbene), a stilbene with a wide range of biological activities. Additionally, his work highlighted the potential of combining pharmacological treatments with the use of natural products of plant origin, which have made significant contributions to the treatment of various diseases. He leaves behind a legacy of groundbreaking research and a lasting influence in the field. He was also involved in research on sugar signaling during plant responses to abiotic and biotic stress factors, as well as the role of signaling molecules in fruit development. His scientific achievements demonstrate that he was, first and foremost, a dedicated scientist – but also a honourable colleague who understood and respected the work of others.
Morpholinium-based Ionic Liquids as Potent Antibiofilm and Sensitizing Agents for the Control of Pseudomonas aeruginosa
Moisture governs diesel biodegradation in sand soil – polystyrene microplastic have a negligible impact
The effect of lead and Acyrthosiphon pisum (Harris) on expression levels of genes encoding enzymes of the pisatin biosynthesis pathway in pea seedlings
Rapid Identification of Rhizobia Nodulating Soybean by a High-Resolution Melting Analysis
Soybean [Glycine max (L.) Merr.] is one of the most important and oldest crops. Due to its ability to form symbiotic interactions with nitrogen-fixing bacteria, it is a valuable source of nitrogen for agriculture and proteins for humans and livestock. In Europe, for instance, in Poland, the soybean cultivation area is still not large but is gradually increasing due to climate change. The lack of indigenous soybean microsymbionts in Polish soils forces the application of commercial strains to establish effective symbioses. Fast and reliable identification methods are needed to study the persistence, competitiveness, and dispersal of bradyrhizobia introduced as inocula. Our study aimed to apply real-time PCR coupled with high-resolution melting curve (HRM) analysis to detect and differentiate bacterial strains occupying soybean nodules. HRM-PCR was performed on crude extracts from nodules using primers specific for recA, a highly conserved nonsymbiotic gene. By comparing them with the reference strains, we were able to identify and assign Bradyrhiobium strains that had been introduced into field locations in Poland. In conclusion, HRM analysis was proven to be a fast and accurate method for identifying soybean microsymbionts and might be successfully used for identifying other legume-nodulating bacteria.