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In this study, the pollinating potential of the red mason bee (Osmia bicornis syn. O. rufa) in seed production of a major ornamental plant - Persian cyclamen (Cyclamen persicum), was evaluated under horticultural farm conditions. The study was conducted under a greenhouse environment for five months, from October to the end of February. The juvenile hormone analogue methoprene supported the termination of bee diapause. Experimental results from Osmia pollination plots were compared with control plots that applied the hand-pollination method. Plants with flowers pollinated by the solitary bee had significantly more fruits than those pollinated by the hand method in November, December and February. In addition, significantly more seeds per capsule were produced by plants pollinated by O. bicornis from December to February. Finally, plants pollinated by Osmia bees produced more seeds than those hand-pollinated at all experimental months. These results showed that if the diapause of O. bicornis is successfully broken, this bee can be a very efficient pollinator in greenhouse environments, even during winter.

This study discusses the longevity and emergence rate of O. rufa males and females after an extended wintering period in artificial conditions. Experimental activation of the wintering bees was carried out every fifteen days, starting at the end of March and finishing at the beginning of June (25 March, 9 April, 24 April, 9 May, 24 May, 8 June). In our study, the shortest emergence time (5 days) was observed in females that overwintered for at least 220 days and were activated at the beginning of May or later. Their mean emergence time in the last three terms was similar and ranged from 4.6 to 5.1 days. Prolonged wintering increased female emergence dynamics in May and June. Half of the emerged males in our study lived up to 28 days when activated during the first term, and up to 15 days when activated during the last one. In females, half of the bees lived up to 64 and 20 days, respectively.

In this study methoprene, a juvenile hormone analogues, was tested as a factor that stimulates the end of diapause, bee activation and emergence. In addition, the survival of bees was checked when combined with an application of methoprene. The experimental activation of wintering bees was carried out once a month between December and March, Three groups of bee cocoons were selected for each activation term: treated with either methoprene or acetone as vehicle control and untreated as controls. After the applications were finished the cocoons were incubated at temperature 26°C. The emerged adult males and females were then kept in the laboratory and fed sucrose solution to evaluate the longevity of bees. The application of juvenile hormone analogue reduced the emergence time of adult bees in December, February and March. The rate of emergence presented in the form of cumulative percentage of emerged adult bees indicated that the bees treated with methoprene started to emerge 1-2 days earlier than bees from acetone and control groups and finished emergence 2-5 days earlier too. Methopren application did not reduce the longevity of the bees after emergence. Moreover, the median longevity of these females was higher than untreated in December and February.

Osmia bicornis syn. O. rufa is a univoltine bee species in which adults fly in spring and the offspring overwinter as cocooned imagoes. The flight period of solitary bees is short, so methods of control for development and emergence time are needed to synchronize the activity of managed pollinators with blooming. In our study, we tested the effectiveness of a juvenile hormone analog for the prevention of winter diapause. Bees developed in settled nests outdoors or in the laboratory (22 °C) until the end of the pre-pupa stage, then cocoons were removed from the nest cells and treated with a JH analog-methoprene-during the pupa and young imago stages. Then, bees were activated at 25 °C until the adults left the cocoons. Topical application of methoprene to the cocoon at the pupa or imago stage induced the emergence of some adult bees in the pre-diapause period, while no adults emerged when the bees were not treated with methoprene. Most adults emerged (about 50%) when treated with methoprene on 3-week-old cocooned imagoes. Bees treated in the pupal stage had a lower emergence rate (20-30%), but adult bees emerged earlier. The emergence time of adults for the laboratory group was, on average, from 70 to 91 days, and that for outdoor groups was from 57 to 72 days.

Neuropeptide B (NPB) is reported to regulate energy homeostasis and metabolism via the NPBWR1 and NPBWR2 receptors in various tissues. However, the molecular mechanisms triggered from their interaction are not well investigated in brown adipose tissue. In this study, we specifically analyzed the role of NPB in controlling brown adipogenesis in rat brown preadipocytes. We first detected the expression of NPBWR1 and NPB on mRNA and protein level in brown preadipocytes and observed that NPB increased viability and proliferation of preadipocytes. Moreover, NPB stimulated expression of adipogenic genes (Prdm16, Ucp1) and suppressed the expression of antiadipogenic preadipocyte factor 1 (Pref1) during the differentiation process. Altogether, this led to an increase in intracellular lipid accumulation during preadipocyte differentiation, coupled with an increase in adrenaline-induced oxygen consumption mediated by NPB. Furthermore, Ucp1 expression stimulated by NPB was attenuated by blockade of p38 kinase. In summary, we conclude that NPB promotes proliferation and differentiation of rat brown preadipocytes via p38-dependent mechanism and plays an important role in controlling brown adipose tissue formation., (© 2021 The Authors. FEBS Open Bio published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

The use of Zophobas morio extracts in the aspect of cellulose hydrolysis is presented for the first time. The aim of this study was to investigate the action of enzymes obtained from Z. morio on cellulose hydrolysis and to determine their influence on the structural properties of cellulose with use the Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). Cellulose hydrolysis products were analyzed by high performance liquid chromatography (HPLC). This analysis indicated that microcrystalline cellulose with smaller particle size was more susceptible to enzymatically treatment. Moreover, our investigation of cellulase activity showed a different profile of the used enzyme during particular developmental stages of Z. morio. Midgut extracts obtained from adult insects are more effective in degrading cellulose than extracts from larvae. The analysis of cellulose hydrolysis confirms that the efficiency of this reaction also depends on the structure of cellulosic materials and internal conditions of enzymatic reaction. In this study the cellulolytic activity of Z. morio midgut extracts showed that these insects could be valuable sources of cellulases., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Every species has certain habitat requirements, which may be altered by interactions with other co-occurring species. These interactions are mostly ignored in predictive models trying to identify key habitat variables correlated with species population abundance/occurrence. We investigated how the structure of the urban landscape, food resources, potential competitors, predators, and interaction between these factors influence the abundance of house sparrow Passer domesticus and the tree sparrow P. montanus in sixty 25 ha plots distributed randomly across residential areas of the city of Poznań (Poland). The abundance of the house sparrow was positively correlated with the abundance of pigeons but negatively correlated with human-related food resources. There were significant interaction terms between abundances of other urban species and habitat variables in statistical models. For example, the abundance of house sparrow was negatively correlated with the abundance of corvids and tree sparrows but only when food resources were low. The abundance of tree sparrows positively correlated with density of streets and the distance from the city center. The abundance of this species positively correlated with the abundance of corvids when food resources were low but negatively correlated at low covers of green area. Our study indicates that associations between food resources, habitat covers, and the relative abundance of two sparrow species are altered by the abundance of other urban species. Competition, niche separation and social facilitation may be responsible for these interactive effects. Thus, biotic interactions should be included not only as an additive effect but also as an interaction term between abundance and habitat variables in statistical models predicting species abundance and occurrence.

The effects of enhanced UV-B radiation on the oogenesis and morpho-anatomical characteristics of the European solitary red mason bee Osmia bicornis L. (Hymenoptera: Megachilidae) were tested under laboratory conditions. Cocooned females in the pupal stage were exposed directly to different doses (0, 9.24, 12.32, and 24.64 kJ/m(2) /d) of artificial UV-B. Our experiments revealed that enhanced UV-B radiation can reduce body mass and fat body content, cause deformities and increase mortality. Following UV exposure at all 3 different doses, the body mass of bees was all significantly reduced compared to the control, with the highest UV dose causing the largest reduction. Similarly, following UV-B radiation, in treated groups the fat body index decreased and the fat body index was the lowest in the group receiving the highest dose of UV radiation. Mortality and morphological deformities, between untreated and exposed females varied considerably and increased with the dose of UV-B radiation. Morphological deformities were mainly manifested in the wings and mouthparts, and occurred more frequently with an increased dose of UV. Cell death was quantified by the Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay (DNA fragmentation) during early stages of oogenesis of O. bicornis females. The bees, after UV-B exposure exhibited more germarium cells with fragmented DNA. The TUNEL test indicated that in germarium, low doses of UV-B poorly induced the cell death during early development. However, exposure to moderate UV-B dose increased programmed cell death. In females treated with the highest dose of UV-B the vast majority of germarium cells were TUNEL-positive., (© 2014 Institute of Zoology, Chinese Academy of Sciences.)

The influence of simulated climate change on body weight and depletion of fat body reserves was studied during diapause in the European solitary bee Osmia rufa L. (Hymenoptera: Megachilidae). Insects (females) were reared and collected from outdoor nests from September to March. One cohort of females was weighed and dissected immediately for analyses, whereas another cohort was subjected to simulated warmer temperature (15°C for 7 d) before analyses. A gradual decline in body mass and fat body content was recorded with declining temperatures from September to January in female bees from natural conditions. Temperature increased gradually from January to March with a further decline in body mass and fat body content. The fat body development index dropped from five in September-October (≈ 89% individuals) to four for the period from November to February (≈ 84% individuals) and further to three in March (95% individuals) before emergence. Simulated warmer winter temperature also resulted in a similar decline in body weight and fat body content; however, body weight and fat body content declined faster. The fat body development index dropped to three in December in the majority of individuals and continued at this level until March just before emergence. Taken together, our data indicate an earlier depletion of fat body reserves under simulated climate change conditions that may impact ovarian development and reproductive fitness in O. rufa.

Females of Osmia rufa, as most species in this genus, enter an obligatory diapause, overwintering as an imago inside a cocoon until the ensuing spring when after emergence - mating, egg development and oviposition occur. Diapause in this species is initiated in November, undergoes 2 months of a pre-wintering period that is terminated at the end of January, after 1 month of maintenance. In this study, factors that affect the termination of adult diapause in the female of this species were investigated. The experimental material consisted of bees that were brought from nests kept in natural conditions 1 month prior to natural termination of diapause. Three different experimental treatments were planned to evaluate the potential effect of methoprene and temperature on diapause termination. During the 5 day experimental period the first group of females was kept at 4°C, the second group at 15°C and the last group of females was kept at 20°C. All groups of females were treated with methoprene topically at a dose of 200 μg. After methoprene application a significant increase (p<0.001) in the size of terminal oocytes was recorded in the three experimental groups. However, no changes in the size of terminal oocytes between acetone treated and untreated control groups were observed. The number of oocytes progressively increased following topical application of methoprene compared to non-treated or acetone treated females. In successive applications of 200 μg methoprene gradual changes in ovary and fat body protein concentration were observed. As compared to controls, protein content in ovaries isolated from methoprene-treated females increased, whereas it decreased in fat body. The least differences in oocyte size and protein concentration in ovary and fat body between control groups and with methoprene application occurred at 4°C. Differences increased and were higher in females kept at 20°C and increased rapidly after methoprene application. Exposure to increasing temperature regimes accelerated the juvenile hormone (JH) induced termination of diapause. Taken together, our results indicate that temperature may play an important role in termination of diapause in O. rufa, but its role is secondary to that played by JH., (Copyright © 2011 Elsevier Ltd. All rights reserved.)