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Commercial blueberry Vaccinium spp. (Ericales: Ericaceae) production relies on insect-mediated pollination. Pollination is mostly provided by rented honey bees, Apis mellifera L. (Hymenoptera: Apidae), but blueberry crop yields can be limited due to pollination deficits. Various hive placement strategies have been recommended to mitigate pollination shortfalls, but the effect of hive placement has received limited formal investigation. This study explores the effects of clumped and dispersed hive placement strategies on honey bee visitation and pollination outcomes in "Bluecrop" and "Duke" fields over 2 years (2021 and 2022) within 2 economically important regions of production in the United States-the Midwest (Michigan) and Pacific Northwest (Oregon and Washington). Clumping hives consistently increased honey bee visitation rate but did not result in higher fruit set, fruit weight, or seed count. Increases in honey bee visitation through clumping could perhaps improve pollination outcomes in more pollination-limited blueberry cultivars and other pollination-dependent crops. Clumping hives is substantially more efficient and cost-effective for beekeepers due to fewer drop locations and could lead to cost savings for both beekeepers and blueberry growers without growers sacrificing pollination levels and crop yields., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America.)

Wild bees are key providers of pollination services in agroecosystems. The abundance of these pollinators and the ecosystem services they provide rely on supporting resources in the landscape. Spatially explicit models that quantify wild bee abundance and pollination services in food crops are built on the foundations of foraging and nesting resources. This dependence limits model implementation as land-cover maps and pollination experts capable of evaluating habitat resource quality are scarce. This study presents a novel approach to assessing crop pollination services using remote sensing data (RSD) as an alternative to the more conventional use of land-cover data and local expertise on spatially explicit models. We used landscape characteristics derived from remote sensors to qualify nesting resources in the landscape and to evaluate the delivery of pollination services by mining bees (Andrena spp.) in 30 fruit orchards located in the Flemish region of Belgium. For this study, we selected mining bees for their importance as local pollinators and underground nesting behavior. We compared the estimated pollination services derived from RSD with those derived from the conventional qualification of nesting resources. We did not observe significant differences (p = 0.68) in the variation in mining bee activity predicted by the two spatial models. Estimated pollination services derived from RSD and conventional characterizations explained 69% and 72% of the total variation, respectively. These results confirmed that RSD can deliver nesting suitability characterizations sufficient for estimating pollination services. This research also illustrates the importance of nesting resources and landscape characteristics when estimating pollination services delivered by insects like mining bees. Our results support the development of holistic agroenvironmental policies that rely on modern tools like remote sensors and promote pollinators by considering nesting resources., (© 2022 The Ecological Society of America.)

Seventy five percent of the world's food crops benefit from insect pollination. Hence, there has been increased interest in how global change drivers impact this critical ecosystem service. Because standardized data on crop pollination are rarely available, we are limited in our capacity to understand the variation in pollination benefits to crop yield, as well as to anticipate changes in this service, develop predictions, and inform management actions. Here, we present CropPol, a dynamic, open, and global database on crop pollination. It contains measurements recorded from 202 crop studies, covering 3,394 field observations, 2,552 yield measurements (i.e., berry mass, number of fruits, and fruit density [kg/ha], among others), and 47,752 insect records from 48 commercial crops distributed around the globe. CropPol comprises 32 of the 87 leading global crops and commodities that are pollinator dependent. Malus domestica is the most represented crop (32 studies), followed by Brassica napus (22 studies), Vaccinium corymbosum (13 studies), and Citrullus lanatus (12 studies). The most abundant pollinator guilds recorded are honey bees (34.22% counts), bumblebees (19.19%), flies other than Syrphidae and Bombyliidae (13.18%), other wild bees (13.13%), beetles (10.97%), Syrphidae (4.87%), and Bombyliidae (0.05%). Locations comprise 34 countries distributed among Europe (76 studies), North America (60), Latin America and the Caribbean (29), Asia (20), Oceania (10), and Africa (7). Sampling spans three decades and is concentrated on 2001-2005 (21 studies), 2006-2010 (40), 2011-2015 (88), and 2016-2020 (50). This is the most comprehensive open global data set on measurements of crop flower visitors, crop pollinators and pollination to date, and we encourage researchers to add more datasets to this database in the future. This data set is released for non-commercial use only. Credits should be given to this paper (i.e., proper citation), and the products generated with this database should be shared under the same license terms (CC BY-NC-SA)., (© 2021 The Ecological Society of America.)

Recently, the concept of Integrated Pest Management (IPM) was further extended into Integrated Pest and Pollinator Management (IPPM). Implementation of IPPM strategies entails the combination of actions for pest and pollinator management providing complementary or synergistic benefits for yield and/or quality of the harvest. The aim of this study was to examine IPPM elements (i.e., mixed hedgerow, nesting boxes for mason bees, Osmia spp.) and demonstrate their impact in the practical context of modern commercial fruit cultivation in a 4-year case study in an intensive 'Conference' pear orchard. The outcomes of visual observations during transect walks and molecular analysis of pollen collected by mason bees, showed the importance of additional floral resources for the presence of mason bees and other pollinating insects in the orchard environment. Pear quality assessments indicated that insect-mediated pollination had a significant positive impact, with a tendency for higher quality pears in the close vicinity of Osmia nesting boxes. However, despite the fact that pear pollen was also detected in Osmia spp. nest cells, the amount and frequency of pear pollen collection for their nest built-up turned out to be rather low. In the same intensive pear orchard studied for pollination effects, we simultaneously demonstrate the impact of a mixed hedgerow to enhance integrated pest control.

Parasites influence wild bee population dynamics and are regarded as one of the main drivers of wild bee decline. Most of these parasites are mainly transmitted between bee species via the use of shared floral resources. Disturbance of the plant-pollinator network at a location can hence disturb the transmission of these parasites. Expansion and intensification of agriculture, another major driver of wild bee decline, often disturbs local plant-pollinator networks by altering the availability and diversity of floral resources. Mass-flowering crops are an extreme example as they provide an abundance of floral resources for a short period of time, substantially altering the present plant-pollinator network. This likely has repercussions on parasite transmission in the pollinator community. Using the bloom of mass-flowering crops we tested the hypothesis that an increase in floral resources can dilute parasite transmission in the pollinator community. To test this, we analysed the presence of parasites in the pollen of the brood cell provisions of Osmia spp., collected from trap nests placed in apple and sweet cherry orchards. We collected pollen at several time intervals during and after mass bloom, and found that pollen collected during mass bloom had significantly lower parasite prevalence compared with pollen collected after mass bloom. Furthermore, using pollen barcoding data we found that the presence of MFCs in pollen was a good predictor for lower parasite prevalence. Taken together, our results indicate that an increase in flower availability can reduce parasite transmission between bees., (Copyright © 2021 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.)

Risk assessment of pesticides involves ecotoxicological testing. In case pesticide exposure to bees is likely, toxicity tests are performed with honey bees (Apis mellifera), with a tiered approach, for which validated and internationally accepted test protocols exist. However, concerns have grown regarding the protection of non-Apis bees [bumble bees (Bombus spp.), solitary and stingless bees], given their different life cycles and therefore distinct exposure routes. Larvae of solitary bees of the genus Osmia feed on unprocessed pollen during development, yet no toxicity test protocol is internationally accepted or validated to assess the impact of pesticide exposure during this stage of their life cycle. Therefore, the purpose of this study is to further validate a test protocol with two solitary bee species (O. cornuta and O. bicornis) to assess lethal and sublethal effects of pesticide exposure on larval development. Larvae were exposed to thiacloprid (neonicotinoid insecticide) mixed in a new, artificial pollen provision. Both lethal (developmental and winter mortality) and sublethal endpoints (larval development time, pollen provision consumption, cocoon weight, emergence time and adult longevity) were recorded. Effects of lower, more environmentally realistic doses were only reflected in sublethal endpoints. In both bee species, thiacloprid treatment was associated with increased developmental mortality and larval development time, and decreased pollen provision consumption and cocoon weight. The test protocol proved valid and robust and showed that for higher doses of thiacloprid the acute endpoint (larval mortality) is sufficient. In addition, new insights needed to develop a standardized test protocol were acquired, such as testing of a positive control for the first time and selection of male and female individuals at egg level., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Recent declines in insect pollinators and the increasing dependence on insect pollination in agriculture present major challenges to ensuring future food production. As part of the effort to deal with this challenge, there is a pressing need to understand growers' perceptions with regard to pollinator diversity and crop pollination management. At present, many growers are dependent on domesticated honey bees ( Apis mellifera ), however, targeted management strategies involving naturally occurring pollinator species might be necessary to ensure future crop pollination. In this study we used semi-structured interviews to explore growers' knowledge about crop pollination and current practices to manage insect pollination in sweet cherry cultivation. Our findings suggest that growers have a clear understanding of the importance of pollination and its determining factors. However, with respect to their current pollination management, growers depend mainly on honey bees and only apply measures to enhance wild pollinator communities to a limited extent. Our study highlights the gap between the growers' perception of the contribution of wild pollinators to crop pollination, and their efforts to manage these species. We conclude that this is due to a lack of communication of recent scientific findings on the contribution of pollinating insects to crop pollination through the information channels that are being used by growers today. It is therefore crucial that scientists, government and other stakeholders work together with growers and communicate scientific evidence as well as practical guidelines to growers.

Kiwifruit has a strong dependence on insect pollinators, and yet the relatively low attractiveness of kiwi flowers to European pollinators may lead to deficits in production. In Italy, due to the scarce efficacy of the honey bee in pollinating kiwifruit, the most used strategy to mitigate this issue is artificial pollination with mass-produced pollen, which incurs high costs and increases the risk of disease; alternative strategies are thus direly needed. The aims of this study are i) to quantify pollination deficit and pollinator contribution to kiwifruit production and quality, and ii) to investigate the release of red mason bees Osmia bicornis (L.) (synonym Osmia rufa) (Hymenoptera Megachilidae) and the use of flower strips (supporting both wild pollinators and the released red mason bees) as strategies for the improvement of kiwifruit pollination. Through manipulative experiments in 3 golden kiwifruit orchards in Northern Italy, we verified that kiwifruit production in the area was significantly improved by insect pollinators, but also suffered from pollination deficit, with average reductions of 9% in fruitlet set, 15% in final fruit set, and 30% in seed number. Our findings confirmed successful population establishment of managed O. bicornis in most sites, and analyses of pollen collected in their provisions indicated that these bees effectively gathered kiwi pollen. While the presence of O. bicornis had limited but statistically significant positive effects on fruit production and quality, the introduction of flower strips had a distraction effect on O. bicornis and other pollinators, leading to some negative consequences on the target crop. This suggests a need for careful management of floral resources to balance the benefits of supporting pollinator populations with the goal of maximizing kiwifruit production; at the same time, the introduction of managed pollinators such as O. bicornis might be especially beneficial to this crop in agroecosystems that are poor in alternative flower resources. [ABSTRACT FROM AUTHOR]

This review paper explores the multifaceted relationship between sweet cherry nutrients and human health, aiming to uncover the comprehensive impact of these bioactive compounds from orchard to wellness. Furthermore, it highlights how advanced crop techniques can be pivotal in optimizing these beneficial compounds. Synthesizing existing literature, the paper examines the diverse bioactive nutrients in sweet cherries, including antioxidants, polyphenols, vitamins, and minerals, and elucidating their mechanisms of action and potential health benefits. From antioxidant properties to anti-inflammatory effects, the paper elucidates how these nutrients may mitigate chronic diseases such as cardiovascular disorders, diabetes, and neurodegenerative conditions. Additionally, it explores their role in promoting gastrointestinal health, enhancing exercise recovery, and modulating sleep patterns. The review discusses emerging research on the potential anti-cancer properties of sweet cherry compounds, highlighting their promising role in cancer prevention and treatment. Furthermore, it delves into the impact of sweet cherry consumption on metabolic health, weight management, and skin health. By providing a comprehensive overview of the current understanding of sweet cherry nutrients and their health effects, this paper offers valuable insights for researchers, healthcare professionals, and consumers interested in utilizing nature's bounty for holistic wellness. [ABSTRACT FROM AUTHOR]

Pollination is one of the most fascinating aspects of insect-plant interactions. Pollen is the male reproductive element of flowering plants, gathered by foraging Honeybees from the male parts of flowering plants called the anther. Guizotia abyssinica (L.f) is an important oilseed crop cultivated in Ethiopia and India, which belongs to the family Asteraceae. Although self-incompatibility is found in Guizotia abyssinica, a higher seed set is experienced in places with an active Honeybees population. Agricultural practices usually focus on inputs such as fertilizer application to improve seed yield of Guizotia abyssinica. However, these practices have little effect on yield if the availability of insect pollination is too low. To fill this gap, an experiment was carried out at Dandi district, West Shao zone, Oromia, Ethiopia to see the effect of Honeybees pollination management as an agronomic input. Pollination management of Honeybees was tested under feeding and non-feeding of colonies management. Pollen was trapped with and without sugar syrup feeding. The results discovered that Honeybees fed sugar syrup collected much more pollen than colonies not fed sugar syrup. The proportion of Guizotia abyssinica pollen collected through sugar syrup feeding of the colony was greater (62.2%), compared to the proportion of Guizotia abyssinica pollen trapped without sugar syrup feeding (37.8%). This indicates that sugar syrup feeding enhances the collection of pollen and probably enhances the pollination efficiency of Honeybees since they visit frequently to fulfill their daily protein requirement of pollen. Therefore, Honeybees pollination services should be included as one of the agronomic inputs with sugar syrup feeding as pollination management that might increase the yield of Guizotia abyssinica since it increases visiting frequency. [ABSTRACT FROM AUTHOR]

Pollinators are fundamental for plant reproduction in natural and agricultural ecosystems. However, their populations are declining worldwide, threatening the functioning of the ecosystem service they provide. The factors driving this change are manifold, but land use changes and interspecific transmission of pathogens between managed and wild bees are prominent. In this context, most research efforts have focused on specific taxa and rarely at the community level, limiting our ability to fully understand the effects of global change on the functioning of plant–pollinator interactions in ecosystems. Here, we investigate the impact of human activities (beekeeping and land use intensity) on the spread of an emergent pathogen Vairimorpha ceranae in Mediterranean wild bee communities inhabiting landscapes with varying levels of anthropogenic disturbance. Plant–pollinator interactions were sampled in nine one‐hectare plots along a gradient of land use (urban structures, croplands and natural vegetation) and beekeeping intensity. We analysed the impact of human disturbances on pollination networks and pathogen prevalence, and applied a network approach to examine whether total effects of species in networks (i.e. direct plus indirect interactions) explain pathogen spread through bee communities. We found that V. ceranae prevalence in honey bees is not a good predictor of the pathogen spread through bee communities. There seems to be a temporal mismatch between pathogen dynamics in managed and wild bees. Networks with more diversity of interactions and more plants showed less pathogen prevalence, but total effect analyses (i.e. combining direct and indirect interactions) failed to explain pathogen transmission across pollination networks. Croplands increased wild bee density, and interactions and species diversity in networks, while shrublands had the opposite effect. Our results highlight the importance of studying pathogen dynamics at the community level and analysing species interaction patterns to improve our understanding of pathogen spread through communities. [ABSTRACT FROM AUTHOR]

Interspecific crop diversity (e.g., intercropping) has been documented to promote sustainability in agroecological systems with benefits for pollination services and insect pollinators. These benefits may also be extended to intraspecific crop diversity (e.g., cultivation of multiple genotypes or cultivars in a production space), but no review to date has examined the benefits of intraspecific crop diversity for pollination and pollinator communities. While mixing cultivars is necessary and a widespread practice for pollination of self-incompatible or male-sterile crops, it is not as widespread for other crop species. However, many other crops have shown reduced yield quantity or quality with self-fertilization due to partial self-sterility, early acting inbreeding depression, and xenia. These crops could thus experience increased production in diverse cultivar mixtures. Cultivar mixtures could also benefit pollinator communities through providing complementary and temporally consistent floral resources, with cascading effects on pollination services. However, successfully implementing cultivar mixtures requires an understanding of how cultivar identity and arrangement affect successful cross-pollination. In this review, we describe the potential benefits of increased intraspecific crop diversity for optimal pollination and pollinator populations across insect-pollinated crops. Additionally, we explore how research advances in cultivar characteristics and insect pollinator behavior and movement, as well as crop pollen flow, can inform cultivar mixtures and spatial arrangements. We find evidence that mixing cultivars, even in self-compatible crops, improves pollination outcomes and yields. Additionally, given insect pollinator behavior and pollen flow, such mixing must occur at relatively small spatial scales. Furthermore, cultivar diversity could ensure successful pollination and resource production for pollinators under extreme weather events. We also discuss costs and benefits of diverse cultivar mixtures from a grower’s perspective and offer suggestions for future research including translating findings within the context of farming systems so that recommendations are practical and achievable. [ABSTRACT FROM AUTHOR]

Pollination services are crucial for maintaining ecological stability and ensuring food security for humans. Managed honey bees, which are economically valuable and are experiencing population growth due to the increasing demand for their products, play a significant role in pollination. To produce high-quality honey, beekeepers often choose natural high meadows, characterized by high plant species richness, for their apiaries. This practice, in turn, may contribute to the pollination of native plants, as managed honey bees are likely to forage on diverse floral resources within these meadows In this study, we investigated the nutritional position of managed bees in the pollination of native plants in Iran using the melissopalynology method to determine the extent of their contribution to the pollination of native plants. Ninety-four honey samples were collected from beekeepers located in the natural pastures of two biodiversity hotspots in Iran (Zagros and Alborz). Then, plant pollens were extracted from the honey and photographed by scanning electron microscopy. In the next step, plant species were identified, and their abundance was calculated. The results showed that managed bees visited 54 plant genera, seven of which were non-native plants. Additionally, more plant species and the highest abundance of pollen were observed at altitudes ranging from 1000 to 3000 m. Therefore, beekeepers set up their hives in this altitude range to obtain high-quality honey. In general, in this study, the results of melissopalynological analysis, involving the identification of plant genera and pollen counts, revealed that managed honey bees likely contributed less than 3% to the pollination of native plant species in Iran. [ABSTRACT FROM AUTHOR]

Sweet cherry (Prunus avium) production relies on modern growing practices like polytunnel coverings to improve yields but this may interrupt arthropod- mediated ecosystem services. The distribution of beneficial arthropods (natural enemies and flower visitors) and the ecosystem services they provide may be affected under polytunnel systems, especially at orchard edges. Across 10 commercial cherry orchards grown in polytunnels, we explored how wildflower strips mitigated edge effects on beneficial arthropods and pest regulation and pollination services. In each orchard, we established a standard wildflower strip (SWS; single cut at the end of the season) and an actively managed wildflower strip (AMWS; regularly cut at 20 cm height) between tree rows and compared this to a conventional control strip (CS). We recorded natural enemies in alleyways and cherry trees post-cherry anthesis (flowering) and flower visitors during and post-cherry anthesis at different distances from the orchard edge (2017-2019). In 2019, we deployed insect prey bait cards in trees to measure pest regulation services and recorded fruit quality (2017-2019) and fruit set (2018-2019) to measure pollination services. Distance from the orchard edge did not affect natural enemy density or diversity in any year or under any alleyway treatment, but pest regulation services decreased towards orchard centres with CS (by 33.0% reduction). Flower visitor density (-34% individuals) and diversity declined with distance from the edge during cherry anthesis. For post-cherry anthesis, marginal negative edge effects were observed for flower visitor density and diversity and behaviour. Overall, fruit set decreased towards the orchard centre while fruit quality increased. Our results suggest that wildflower strips are an effective tool to mitigate edge effects on pest regulation services but have limited effects on flower visitors and pollination. [ABSTRACT FROM AUTHOR]

Background: Pollination is crucial to obtaining optimal blueberry yield and fruit quality. Despite substantial investments in seasonal beekeeping services, blueberry producers consistently report suboptimal pollinator visitation and fruit set in some cultivars. Flower morphology and floral rewards are among the key factors that have shown to contribute to pollinator attraction, however little is known about their relative importance for improving yield in the context of plant breeding. Clarifying the relationships between flower morphology, nectar reward content, pollinator recruitment, and pollination outcomes, as well as their genetic components, can inform breeding priorities for enhancing blueberry production. In the present study, we measured ten flower and nectar traits and indices of successful pollination, including fruit set, seed count, and fruit weight in 38 southern highbush blueberry genotypes. Additionally, we assessed pollinator visitation frequency and foraging behavior over two growing seasons. Several statistical models were tested to optimize the prediction of pollinator visitation and pollination success, including partial least squares, BayesB, ridge-regression, and random forest. Results: Random forest models obtained high predictive abilities for pollinator visitation frequency, with values of 0.54, 0.52, and 0.66 for honey bee, bumble bee, and total pollinator visits, respectively. The BayesB model provided the most consistent prediction of fruit set, fruit weight, and seed set, with predictive abilities of 0.07, -0.08, and 0.42, respectively. Variable importance analysis revealed that genotypic differences in nectar volume had the greatest impact on honey bee and bumble bee visitation, although preferences for flower morphological traits varied depending on the foraging task. Flower density was a major driving factor attracting nectar-foraging honey bees and bumble bees, while pollen-foraging bumble bees were most influenced by flower accessibility, specifically corolla length and the length-to-width ratio. Conclusions: Honey bees comprised the majority of pollinator visits, and were primarily influenced by nectar volume and flower density. Corolla length and the length-to-width ratio were also identified as the main predictors of fruit set, fruit weight, seed count, as well as pollen-foraging bumble bee visits, suggesting that these bees and their foraging preferences may play a pivotal role in fruit production. Moderate to high narrow-sense heritability values (ranging from 0.30 to 0.77) were obtained for all floral traits, indicating that selective breeding efforts may enhance cultivar attractiveness to pollinators. [ABSTRACT FROM AUTHOR]

Habitat loss is a primary driver of global biodiversity decline, negatively impacting many species, including native bees. One approach to counteract the consequences of habitat loss is through restoration, which includes the transformation of degraded or damaged habitats to increase biodiversity. In this review, we survey bee habitat restoration literature over the last 14 years to provide insights into how best to promote bee diversity and abundance through the restoration of natural landscapes in North America. We highlight relevant questions and concepts to consider throughout the various stages of habitat restoration projects, categorizing them into pre-, during-, and post-restoration stages. We emphasize the importance of planning speciesand site-specific strategies to support bees, including providing floral and non-floral resources and increasing nest site availability. Lastly, we underscore the significance of conducting evaluations and long-term monitoring following restoration efforts. By identifying effective restoration methods, success indicators, and areas for future research, our review presents a comprehensive framework that can guide land managers during this urgent time for bee habitat restoration. [ABSTRACT FROM AUTHOR]

Highbush blueberry pollination depends on managed honey bees (Apis mellifera L.) for adequate fruit sets; however, beekeepers have raised concerns about the poor health of colonies after pollinating this crop. Postulated causes include agrochemical exposure, nutritional deficits, and interactions with parasites and pathogens, particularly Melisococcus plutonius [(ex. White) Bailey and Collins, Lactobacillales: Enterococcaceae], the causal agent of European foulbrood disease, but other pathogens could be involved. To broadly investigate common honey bee pathogens in relation to blueberry pollination, we sampled adult honey bees from colonies at time points corresponding to before (t1), during (t2), at the end (t3), and after (t4) highbush blueberry pollination in British Columbia, Canada, across 2 years (2020 and 2021). Nine viruses, as well as M. plutonius , Vairimorpha ceranae, and V. apis [Tokarev et al. Microsporidia: Nosematidae; formerly Nosema ceranae (Fries et al.) and N. apis (Zander)], were detected by PCR and compared among colonies located near and far from blueberry fields. We found a significant interactive effect of time and blueberry proximity on the multivariate pathogen community, mainly due to differences at t4 (corresponding to ~6 wk after the beginning of the pollination period). Post hoc comparisons of pathogens in near and far groups at t4 showed that detections of sacbrood virus (SBV), which was significantly higher in the near group, not M. plutonius , was the primary driver. Further research is needed to determine if the association of SBV with highbush blueberry pollination is contributing to the health decline that beekeepers observe after pollinating this crop. [ABSTRACT FROM AUTHOR]

Sitobion miscanthi and Schizaphis graminum (Rondani) are the 2 main aphid species that occur simultaneously, causing significant loss to wheat production. Acetamiprid has been used to control a variety of pests, including aphids. In this study, the sublethal effect of acetamiprid on S. miscanthi and S. graminum was evaluated using life-table analyses. The results showed that acetamiprid has a high toxicity to S. miscanthi and S. graminum with a LC50 of 1.90 and 3.58 mg/L at 24 h, respectively. The adult longevity and fecundity of S. miscanthi and S. graminum F0 generation were significantly reduced after being exposed to a sublethal concentration of acetamiprid. Additionally, the sublethal concentration of acetamiprid had negative transgenerational effects on S. miscanthi and S. graminum , which showed a significant decrease in fecundity and population life-table parameters involving age-stage-specific survival rate (s xj ), age-specific survival rate (l x ), and intrinsic rate of increase (r). Furthermore, the population projections showed that the total population size of S. miscanthi and S. graminum was significantly lower in the aphid group exposed to sublethal concentration of acetamiprid compared to the control group. These results suggest that sublethal concentration of acetamiprid suppresses the population growth of S. miscanthi and S. graminum. This finding is beneficial to the control of wheat aphids, and is important to fully understand the role of acetamiprid in integrated pest management. [ABSTRACT FROM AUTHOR]

One method of crop protection is the application of a widely used group of pesticides—pyrethroids. As xenobiotics, sub-lethal doses of insecticides cause stress in pests, resulting in a change in the shape and size of their organs or bodies. The stress caused by pesticides may lead to acute destabilization of development, but also to transgenerational canalization through the process of genetic assimilation. Fluctuating asymmetry (FA), small random deviations between the right and left sides of bilaterally symmetrical traits, is an outcome of developmental instability and is a measurable indicator of phenotypic response to stress. We exposed four populations of the seed beetle Acanthoscelides obtectus to sub-lethal doses of cypermethrin for ten generations in a laboratory evolution experiment. Using geometric morphometrics, we analyzed size and shape changes and the level of fluctuating asymmetry in untreated beetles and in samples from the fifth and tenth generation. Exposure over ten generations led to an increase in the body size of the beetles, shortening of their pronotum and elongation of their thorax and abdomen. After ten generations of exposure to cypermethrin, FA levels decreased, indicating a canalization of development. This study provides new insights into the phenotypic markers of environmental pollution from agricultural activities. [ABSTRACT FROM AUTHOR]

Cherry (Prunus avium) fruits are important sources of vitamins, minerals, and nutrients in the human diet; however, they contain a large stone, making them inconvenient to eat 'on the move' and process. The exogenous application of gibberellic acid (GA3) can induce parthenocarpy in a variety of fruits during development. Here, we showed that the application of GA3 to sweet cherry unpollinated pistils acted as a trigger for fruit set and permitted the normal formation of fruit up to a period of twenty-eight days, indicating that gibberellins are involved in the activation of the cell cycle in the ovary wall cells, leading to fruit initiation. However, after this period, fruit development ceased and developing fruit began to be excised from the branch by 35 days post treatment. This work also showed that additional signals are required for the continued development of fully mature parthenocarpic fruit in sweet cherry. [ABSTRACT FROM AUTHOR]

Extreme heat poses a major threat to plants and pollinators, yet the indirect consequences of heat stress are not well understood, particularly for native solitary bees. To determine how brief exposure of extreme heat to flowering plants affects bee behaviour, fecundity, development and survival we conducted a no-choice field cage experiment in which Osmia lignaria were provided blueberry (Vaccinium corymbosum), phacelia (Phacelia tanacetifolia) and white clover (Trifolium repens) that had been previously exposed to either extreme heat (37.5°C) or normal temperatures (25°C) for 4 h during early bloom. Despite a similar number of open flowers and floral visitation frequency between the two treatments, female bees provided with heat-stressed plants laid approximately 70% fewer eggs than females provided with non-stressed plants. Their progeny received similar quantities of pollen provisions between the two treatments, yet larvae consuming pollen from heat-stressed plants had significantly lower survival as larvae and adults. We also observed trends for delayed emergence and reduced adult longevity when larvae consumed heat-stressed pollen. This study is the first to document how short, field-realistic bursts of extreme heat exposure to flowering host plants can indirectly affect bee pollinators and their offspring, with important implications for crop pollination and native bee populations. [ABSTRACT FROM AUTHOR]

The launch is considered the most stressful rocket flight stage due to the hypergravity occurrences. The possibility of using honey bees (Apis mellifera) as the extraterrestrial pollinator depends on their ability to reproduce correctly after experiencing hypergravity. The described study aims to verify the impact of a launching rocket’s acceleration on honey bee queen’s egg-laying behavior. Four artificially inseminated A. mellifera carnica queens were placed in the Human Training Centrifuge and given to the acceleration pattern of the launching Soyuz rocket. Next, the data on the number of food stores, eggs, larvae, and worker and drone pupae were collected from the test and control hives using the modified Liebefeld method. The pilot study results imply that accelerated queen’s egg-laying behavior may change twofold: limiting or maximizing the number of laid eggs, with the control queen egg-laying rate remaining stable for all samples. The number of drone pupae is greater for the test sample colonies, with its earlier appearance in the hive. No impact on overwintering success was observed. Authors indicate limitations of the results and a need to continue the study to verify the occurrence of anomalies potentially related to the examined factor. [ABSTRACT FROM AUTHOR]

Weed management is challenging for vegetable crops that are highly sensitive to weed competition, such as onions. Thrips (Thysanoptera: Thripidae) are major insect pests of onions, causing damage through feeding, and vectoring bacterial pathogens causing bulb rot. Both thrips and their associated pathogens are known to survive on many weed species in onion growing regions. Combining weeding with biopesticides may synergistically manage thrips and reduce disease prevalence. However, disturbances from weeding may negatively impact natural enemies. We estimated the effects of organic weed management and biopesticides on weed density, thrips and natural enemy activity, disease severity, and yield. The experiment was a randomized complete block design, with 4 replications of each weeding (control, tine-weeded twice, tine-weeded 4 times, and hand-weeded) and biopesticide (control, OxiDate 2.0, Serenade) combination. Arthropods were monitored using yellow sticky cards, and weed counts, marketable yield, and bulb rot prevalence were estimated. Hand-weeding resulted in the lowest weed density and thrips abundance. Additionally, hand-weeding produced a 9× higher yield compared to all other treatments. Significant interactions were observed between tine-weeding and biopesticide treatments on the prevalence of bulb rot. Natural enemy abundance was slightly negatively impacted by weeding, dependent on the year. DNA metabarcoding results showed high parasitoid diversity in this onion system and high numbers of reads for multiple genera containing important known biological control agents. Our study suggests hand-weeding is necessary in the southeast for maximum onion yield. Future research should focus on exploring the impact of management on natural enemy communities in onion systems on a large scale. [ABSTRACT FROM AUTHOR]

Scopolia carniolica Jacq. is a perennial plant from the family Solanaceae. The study objective was to examine floral traits that may be important for interactions with floral visitors (i.e., blooming phenology, floral micromorphology, nectary characteristics, nectar quantity, nectar sugar composition, and pollen production). In S. carniolica, papillae, numerous non-glandular trichomes, and a few glandular trichomes were present on the inner corolla epidermal surface. Lipids, acidic lipids, tannins, and alkaloids were present in the non-glandular trichomes and in the corolla cells. The discoid-type nectary was located at the base of the ovary. Floral nectar was released through nectarostomata. The process of nectar release started in the bud stage (ca. 5–8 h before corolla opening) and continued to the 4th day of anthesis. The amount of secreted nectar peaked in 2-day-old flowers. The amount of produced nectar, nectar sugar concentration, and sugar mass varied significantly across years. On average, the total mass of sugars in the nectar was 0.54 mg/flower. S. carniolica produced sucrose-dominant nectar with no glucose. The sugar proportions did not differ during the flowering season. On average, 1.95 mg of pollen per flower was produced. Among floral visitors, bumblebees were most frequently noted, accounting for 79.7% of the total number of floral visitors to S. carniolica flowers. The species can be used in early spring ornamental arrangements to support the food supply for insects, mainly bumblebees. [ABSTRACT FROM AUTHOR]

Introduction: The self-incompatibility system in sweet cherry (Prunus avium L.) prevents fertilization with own or genetically related pollen, and is genetically determined by the multi-allelic S-locus. Therefore, determining S-alleles is crucial for plant breeding and fruit production, as it enables the selection of compatible combinations of S-genotypes for successful pollination. Methods: In this study, S-alleles were identified in a total of 260 genotypes from the Caucasian region, the species' center of origin. S-allele genotyping was conducted using PCR fragment length analysis with the standard marker PaConsI-F/R2 and reference genotypes, complemented by sequence analysis through amplicon deep sequencing. Results and discussion: The genotypes collected from Azerbaijan and Turkey exhibit a high allelic richness at the S-locus, particularly compared to modern sweet cherry cultivars worldwide. Nine previously undescribed S-alleles were identified and designated as S45, S46, S47, S48, S49, S50, S51, S52 and S53. Given the expected high diversity for other traits, this plant material represents a valuable resource for further breeding research and introgression of new traits in future breeding programs. Furthermore, our results underscore that fragment length alone may not be sufficient for unambiguous assignment of S-alleles due to minimal length differences between different alleles. To address this issue, an Sallele reference ladder was developed using the rich diversity for precise assignment of the S-alleles. This tool can be applied in future experiments as a robust and cost-effective method for accurate S-genotyping across different runs and laboratories. Additionally, several selected S-genotypes were planted in a trial field and will be maintained as an S-allele reference collection. [ABSTRACT FROM AUTHOR]

This study evaluates the engineering properties of various carriers for date palm pollen grains, including Wheat Flour (WF), Wheat Bran (WB), Banana Peels (BP), Male Spathe Flowers (MSF), and Female Bunch Strands (FBS). The focus is on bulk density, repose angle, dynamic coefficient of friction, and terminal velocity. Bulk density ranged from 0.321 to 0.831 g cm-3, with date palm pollen grain (DPP) showing the highest value, suggesting efficient storage but potential flowability issues. Repose angles varied from 24 to 47 degrees; DPP and DPP+FBS (Female bunch strands) had the lowest angles, favoring smooth flow during pollination, while wheat flour (WF) had the highest, indicating resistance and clumping. Friction analysis across different surfaces (acrylic, PVC, aluminum, and stainless steel) highlighted material-surface interactions. Terminal velocity results showed DPP with a balanced value of 0.96 m s-1, while mixtures like DPP+FBS and DPP+BP (banana peels) had low to moderate velocities (0.6 m s-1 and 1.02 m s-1), enhancing dispersion. DPP and its mixtures, especially DPP+FBS, exhibited favorable pollination properties with good flowability and moderate friction, promoting efficient distribution. In contrast, higher friction materials like FBS could hinder application. The study emphasizes the need to select carriers with optimal density, repose angle, and friction to improve pollination efficiency, supporting better agricultural outcomes. Mixtures DPP+FBS and DPP+MSF emerged as the best option, balancing physical, mechanical and aerodynamic characteristics for effective pollination. [ABSTRACT FROM AUTHOR]

The present study focused on the impact of weather parameters over the foraging efficiency and pollination potential of stingless bees, Tetragonula iridipennis in tomato ecosystem which was located in Coimbatore district, Tamil Nadu, India. The maximum foraging activity (outgoing bees - 24.56/5 min, Pollen foragers - 8.64 bees/5 min, nectar foragers - 13.54 bees/5 min and resin foragers - 2.89 bees/5 min) was observed between 10.00 - 12.00 h during the study period. The activity of stingless bees was minimal between 06.00 - 08.00 h when the foraging commences. The maximum temperature was significantly positively associated with the foraging potential and average relative humidity was negatively correlated. Heavy rainfall also affects their capacity of flight thereby the foraging activity could be restricted to the favourable time of the day. The monthly pooled averages recorded throughout the summer season, revealed that the peak foraging activity of outgoing and incoming foragers was observed in March, followed by April, while the lowest activity was recorded in May. Peak foraging activity occurred in early summer, likely due to greater resource availability and favourable weather conditions. These weather-related factors reveal how stingless bees adapt to environmental conditions, showing their sensitivity and strategic adjustments in response to climate variability and change. Moreover, the potential pollination services offered by stingless bees yielded significant results. With the aid of stingless bee pollination, the yield of tomato fruit per plant reached 3.53 kg, and the fruit's length and diameter measured up to 3.92 cm and 4.21 cm, respectively. Additionally, the weight of 100 seeds per tomato fruit was recorded at 0.31 g. The overall quality of the tomato fruit was notably enhanced by the pollination assistance from T. iridipennis., Competing Interests: Declarations. Ethical approval: This study does not contain any studies with human or animal participants performed by authors. Consent to participate: The authors agreed with the content and all gave explicit content to submit and obtained consent from the responsible authorities at the institution where the work has been carried out. Consent to publish: The authors agreed to publish this manuscript. Competing interest: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Pollination is a crucial ecosystem service, yet pollinator species diversity is declining as a result of factors such as climate change, habitat loss and agricultural intensification. While previous studies have often examined the extreme scenario of complete pollinator removal, showing negative impacts on plant reproductive success, we take a more realistic approach by focusing on the effects of decreasing pollinator diversity. Our global meta-analysis reveals a notable negative impact of reduced pollinator species diversity on plant reproductive success measures, such as seed set, fruit set and fruit weight. Notably, this effect varies across plant families, impacting both self-incompatible and self-compatible species. We also find that wild plant species suffer more than cultivated ones. Furthermore, the loss of invertebrate, nocturnal and wild pollinators has a more substantial impact than the loss of vertebrate, diurnal or managed pollinators. Overall, our findings consistently underscore the positive role of biodiversity in maintaining ecosystem functioning, highlighting the urgency of mitigating factors that lead to the decline in pollinator species diversity., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Agricultural pesticides have historically been a critical tool in controlling pests and diseases, preventing widespread suffering and crop losses that led to catastrophes such as the Great Irish Famine (1845-1852) and the Cotton Boll Weevil Infestation (1915-1916). However, their usage has brought challenges, including resistance development, secondary pest outbreaks, harm to non-target organisms like pollinators, and environmental contamination. In response to these concerns, integrated pest management (IPM) has emerged as a comprehensive approach, emphasizing non-chemical pest control methods such as cultural practices, biological control, and crop rotation, with pesticides as the last resort. IPM has evolved, influenced by regulations like the Food Quality Protection Act (FQPA), which prioritizes human health protection, especially for children. The development of systemic pesticides, particularly neonicotinoids, introduced a more efficient and targeted pest control method within the IPM framework. However, they have also raised concerns due to their potential adverse effects on pollinators. In recent years, integrated pest and pollinator management (IPPM) has emerged as an enhanced approach, integrating pollinator health considerations into pest management strategies. In this article, we discuss this new approach, and briefly present an example of a modifying pesticide program in Pennsylvania apple orchards to illustrate the application of IPPM, in order to highlight the importance of IPPM in sustaining agriculture, protecting vital pollinators, and maintaining effective pest control practices. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., (© 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.)

Predictive modelling tools can be used to support the design of agricultural landscapes to promote pollinator biodiversity and pollination services. Despite the proliferation of such modelling tools in recent decades, there remains a gap in synthesising their main characteristics and representation capacities. Here, we reviewed 42 studies that developed non-correlative models to explore the impact of land use and land cover changes on bee populations, and synthesised information about the modelled systems, modelling approaches, and key model characteristics like spatiotemporal extent and resolution. Various modelling approaches are employed to predict the biodiversity of bees and the pollination services they provide, with a prevalence of models focusing on wild populations compared to managed ones. Of these models, landscape indicators and distance decay models are relatively simple, with few parameters. They allow mapping bee visitation probabilities using basic land cover data and considering bee foraging ranges. Conversely, mechanistic or agent-based models delineate, with varying degrees of complexity, a multitude of processes that characterise, among others, the foraging behaviour and population dynamics of bees. The reviewed models collectively encompass 38 ecological, agronomic, and economic processes, producing various outputs including bee abundance, habitat visitation rate, and crop yield. To advance the development of predictive modelling tools aimed at fostering pollinator biodiversity and pollination services in agricultural landscapes, we highlight future avenues for increasing biophysical realism in models predicting the impact of land use and land cover changes on bees. Additionally, we address the challenges associated with balancing model complexity and practical usability., (© 2024 Cambridge Philosophical Society.)

Background: The use of DNA metabarcoding has become an increasingly popular technique to infer feeding relationships in polyphagous herbivores and predators. Understanding host plant preference of native and invasive herbivore insects can be helpful in establishing effective integrated pest management (IPM) strategies. The invasive Halyomorpha halys and native Pentatoma rufipes are piercing-sucking stink bug pests that are known to cause economic damage in commercial fruit orchards., Results: In this study, we performed molecular gut content analysis (MGCA) on field-collected specimens of these two herbivorous pentatomids using next-generation amplicon sequencing (NGAS) of the internal transcribed spacer 2 (ITS2) barcode region. Additionally, a laboratory experiment was set up where H. halys was switched from a mixed diet to a monotypic diet, allowing us to determine the detectability of the initial diet in a time series of ≤3 days after the diet switch. We detected 68 unique plant species from 54 genera in the diet of two stink bug species, with fewer genera found per sample and a smaller diet breadth for P. rufipes than for H. halys. Both stink bug species generally prefer deciduous trees over gymnosperms and herbaceous plants. Landscape type significantly impacted the observed genera in the diet of both stink bug species, whereas season only had a significant effect on the diet of H. halys., Conclusion: This study provides further insights into the dietary composition of two polyphagous pentatomid pests and illustrates that metabarcoding can deliver a relevant species-level resolution of host plant preference. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

Remote sensing of spectral reflectance is a crucial parameter in precision agriculture. In particular, the visual color produced from reflected light can be used to determine plant health (VIS-IR) or attract pollinators (Near-UV). However, the UV spectral reflectance studies largely focus on non-crop plants, even though they provide essential information for plant-pollinator interactions. This literature review presents an overview of UV-reflectance in crops, identifies gaps in the literature, and contributes new data based on strawberry cultivars. The study found that most crop spectral reflectance studies relied on lab-based methodologies and examined a wide spectral range (Near UV to IR). Moreover, the plant family distribution largely mirrored global food market trends. Through a spectral comparison of white flowering strawberry cultivars, this study discovered visual differences for pollinators in the Near UV and Blue ranges. The variation in pollinator visibility within strawberry cultivars underscores the importance of considering UV spectral reflectance when developing new crop breeding lines and managing pollinator preferences in agricultural fields. [ABSTRACT FROM AUTHOR]

Pollinators play important roles in providing pollination services, maintaining biodiversity, and boosting crop production. Even though pollinators are essential to the environment and agriculture, their decline has been noted across multiple studies in the recent past. Both natural and anthropogenic factors have contributed to their decline. Much of the focus has been placed on climate change, habitat loss, pests and pathogens, and synthetic pesticides, but relatively little is known about the effects of biopesticides. Biopesticides are biological control agents derived from living organisms and are classified into three groups: microbial, biochemical, and plant-incorporated protectant-based products. Biopesticides are formulated similarly to their synthetic counterparts and are readily available and used within urban and agricultural settings by pest management experts and household residents. The general public and much scientific literature support the prevailing idea that biopesticides are environmentally safe and pollinator friendly in comparison with synthetic versions. However, such generalizations are based on studies with a few key pollinator species and may not be relevant to several other species that provide crop pollination services. Studies focused on native pollinators have shown that some biopesticides have lethal and sublethal effects. Because each biopesticide exhibits varying effects across pollinator species, it could be dangerous to generalize their non-toxicity across taxa and environmental settings. In this article, recent research in this direction is discussed. [ABSTRACT FROM AUTHOR]

The western honey bee (Apis mellifera L.) is the most globally used managed pollinator species, but it can have limited pollinating activity on nectariferous crops displaying anthers isolated from stigmas, i.e., when anthers are spatially or temporally separated from stigma within or between flowers. We supplemented honey bee colonies with pollen in the combs or in paste form laid on top of the hive frames to test if these treatments could reduce their pollen foraging and increase their pollinating activity in a monoecious and nectariferous cultivar of cantaloupe melon (Cucumis melo L.), in comparison with control colonies not supplemented. We recorded the pollen forager density per flower, the number of pollen grains deposited per stigma and their resulting fruit set, seed set and fruit mass, before and after the colony pollen supplementations. The number of pollen grains deposited by honey bees on stigmas increased gradually after pollen supplementation in the combs. But pollen foraging decreased only moderately, and no effect could be observed on any yield component except the seed set. On the other hand, there was no effect of the pollen paste laid on top of the frames either on stigmatic pollen loads, on colony pollen foraging or on any yield component. Supplementing honey bee colonies with pollen in the combs can therefore be an effective means for increasing their pollinating activity in nectariferous crops displaying anthers isolated from stigmas, e.g., Amaryllidaceae, Apiaceae, Cucurbitaceae, avocado, all hybrid seed productions. The context for the potential use of pollen substitutes is discussed. [ABSTRACT FROM AUTHOR]

Solitary bees are in constant decline due to climate change, pesticide toxicity, and habitat loss. Provision of nesting sites is an important conservation strategy. Various factors affect bee nesting, including parasitism, entrance orientation, nesting substrate type, and diameter. This study explored the impact of nesting substrate, cavity diameter, and entrance orientation on solitary bee nesting preferences. Additionally, it investigated the influence of landscape type and seasonality on bee nesting efficiency which is the ability of a bee to successfully establish nest. Trap nests were placed at eight locations, representing five landscapes (forest, desert, agriculture, peri-urban, and urban). These trap nests had five different nesting substrates (bamboo reeds, wooden blocks, wooden logs, mud blocks, and paper tubes). At each location, four traps were set in all directions. The results showed maximum cavity occupation in south-facing nests. Peri-urban landscapes were the most favored for nesting, followed by forests. Solitary bees primarily preferred bamboo reeds for nesting, with peak occupation from April to June. Bees favored cavities with 6- and 8-mm entrance diameters, while wasps occupied smaller diameters (< 5 mm). Overall, bee species occupied fewer nests compared to parasitic wasps. Future research should explore brood chamber numbers and species-specific nesting preferences for bees, along with the impact of cavity microclimate on bee growth. [ABSTRACT FROM AUTHOR]

Wild bees (Hymenoptera: Apoidea) play an important role as pollinators of many crops and managed populations of Osmia spp. (Megachilidae), through the installation of trap-nests, proved to be efficient in several fruit orchards. In order to optimize the trap-nest protocols, it is necessary to understand which environmental factors play a major role in the reproductive success of these bees. Here, we studied how climate, land use and vegetation affect nest occupation rate (OR, i.e. total number of colonized tunnels/total number of tunnels in the trap-nest), brood productivity (BP, i.e. total number of brood cells built in a completed nest tunnel) and parasitism rate (PR, i.e. total number of parasitized brood cells/BP) in Osmia bees nearby almond orchards in South-East Spain, a largely understudied Mediterranean area. We found that the summer solar radiation positively influenced all three parameters, while spring solar radiation positively affected OR and BP, and negatively PR. Higher abundance of pastures and forests compared with crops increased OR, though not BP, and reduced PR. Vegetation evenness and diversity of dominant plant species also positively affected OR and BP, while they were unimportant for PR. OR was not affected by climate, but BP increased with maximum temperature in the warmest month and decreased with temperature annual range. PR also increased with high temperature, as well as with precipitation. Arid conditions limited OR and BP and boosted parasitism. Overall, it seems that Osmia bees nearby almond field in this area would benefit from trap-nest installation in well solar-radiated, hot and humid sites with a diverse vegetation. Since we have also found a negative association between PR and BP in nests with at least one parasitized cell, environmental conditions which improve productivity will also likely reduce parasitism in these bees. Implications for insect conservation Optimization of trap-nesting protocols for maintaining abundant Osmia populations is crucial to an effective use of these bees as managed pollinators. In our study we suggest that trap-nests locations should be chosen also taking into account a number of local climatic and habitat factors, given their importance in affecting key traits of reproductive success in these solitary bees. [ABSTRACT FROM AUTHOR]

Honey bees have significant ecological and economic value as important pollinators, but they are continuously exposed to various environmental stressors, including insecticides, which can impair their health and cause colony decline. (1) Background: Cognitive abilities are vital for the functional maintenance of honey bees; however, it remains unknown if chronic, low-dose exposure to thiacloprid during the larval stage impairs the cognitive abilities of emerged adult honey bees. (2) Methods: To explore this question, honey bee larvae were fed 0, 0.5, and 1.0 mg/L thiacloprid during their developmental phase. Then, the cognitive (i.e., olfactory learning and memory) abilities of adult honey bees were quantified to assess the delayed impacts of early-stage thiacloprid exposure on adult honey bee cognition. Neural apoptosis and transcriptomic level were also evaluated to explore the neurological mechanisms underlying these effects. (3) Results: Our results revealed that chronic larval exposure to sublethal thiacloprid impaired the learning and memory abilities of adult honey bees by inducing neuronal apoptosis and transcriptomic alterations. (4) Conclusions: We highlighted a previously unknown impairment caused by thiacloprid in honey bees. [ABSTRACT FROM AUTHOR]

Increasing agricultural intensification, combined with land transformation and fragmentation, poses significant threats to biodiversity. While extensively cultivated landscapes serve as vital refuges against biodiversity loss, they are modified by land abandonment and intensification. Orchard meadows in Central Europe represent traditional extensive land management systems, exhibiting high biodiversity. Comprising cultivated grasslands and scattered fruit trees, orchard meadows feature structures rich in different habitats supporting a diverse flora and fauna. However, their decreasing economic importance in recent decades has resulted in severe degradation or abandonment. Despite their importance for biodiversity conservation, there remains no comprehensive overview of orchard meadow biodiversity and management in Central Europe. This review aims to summarize existing knowledge on orchard meadows' role in biodiversity conservation and the effects of management practices on habitat diversity and quality at both smaller (structure and microhabitats, local scale) and larger scales (surrounding landscape, regional scale). The first part focuses on orchard meadow biodiversity, including both plants and animals and their link to landscape-scale factors. Biodiversity in orchard meadows is predominantly affected by patch size, determining species richness and composition, and connectivity to neighbouring orchard meadows, influencing species migration and recolonization success. The second part evaluates management impacts, illustrating differences in the benefits of mowing versus grazing across taxonomic groups. An intermediate management intensity for orchard meadows determines their conservation value in terms of species composition, varying among different taxonomic groups. To prevent area loss and abandonment of orchard meadows, we advocate for political and public support, along with incentives for farmers to maintain their biodiversity. [ABSTRACT FROM AUTHOR]

Communities are characterized by the dominance of a few species, which are crucial for shaping communities. Bees compete for scarce resources, and offer an ideal system to study the effect of dominance on the diversity of bees. The effect of bee dominance is studied predominantly for the western honeybee, which often is illustrated negative in introduced sites. Solitary bees, stingless bees, native honeybees and bumblebees can also be dominant on flowers. We test the hypothesis that dominance, regardless of the identity of the species, negatively influence diversity of bees on flowers. We analyzed 95,160 visits of 58 species of bees on 59,211 flowers of 12 plant species for five years. Before the analyses, the visitors were grouped into honeybees, solitary bees, and stingless bees. Proportion of the total abundance accounted by the most abundant species was considered as the measure of dominance. Dominance was negatively associated with richness and visitation rate of bees, but identity of bee taxonomic group predicted the magnitude of the effects. Richness decreased with the dominance of honeybees and solitary bees, but not with the stingless bees. Visits of honeybees decreased when solitary bees dominated the visits. Visits of solitary bees decreased when honeybees or stingless bees dominated the flowers. We have shown that native bees of different taxonomic groups can exert a similar negative effect on bee diversity in flowers as invasive and managed species do. Honeybees and stingless bees, though native to some parts, deteriorate bee diversity if unnecessarily augmented to ecosystems for beekeeping. [ABSTRACT FROM AUTHOR]

Optimal fruit production from many tree crops relies on the transfer of cross-pollen between trees of different cultivars rather than the transfer of self-pollen between trees of the same cultivar. However, many orchards are established with wide blocks of single cultivars, which can result in high percentages of self-fertilised fruit and sub-optimal yield and quality. We aimed to determine whether outcrossing rates and yield of Hass avocado fruit decline with increasing distance from polliniser trees of cultivar Shepard and whether selfed fruit are smaller than outcrossed fruit. Outcrossing rates declined from 49% at six trees (40 m) from a block of Shepard trees to 30% at thirty trees (160 m) from a block of Shepard trees. Tree yield across this distance declined by 44% as a result of a 69% decline in the number of outcrossed fruit per tree, without a significant decline in the number of selfed fruit per tree. Outcrossed Hass fruit were 12% heavier than selfed Hass fruit, with 3% greater diameter and 5% greater length. The study results demonstrate the importance of interplanting Type B avocado pollinisers closely with Type A Hass trees to increase fruit yield and size. [ABSTRACT FROM AUTHOR]

Understanding how working landscapes can maintain viable wildlife populations is key to evaluating their conservation potential. We assessed the potential of intensively managed conifer forests for supporting healthy, productive bee populations in one of the major timber‐growing regions of the world, the Pacific Northwest. We examined the direct effect of the number of years post‐harvest and other forest characteristics on flowering plant and bee communities and their indirect effect on parasite prevalence (Apicystis spp., Ascosphaera spp., and Crithidia spp.) and reproduction of a native, forest‐dwelling solitary bee (Osmia lignaria). Forest characteristics, including the time elapsed since harvest, influenced floral and bee community diversity and abundance and indirectly impacted parasite prevalence and offspring production. We found that increased bee diversity was associated with reduced parasite prevalence—consistent with a dilution effect—but the strength of the relationship varied across the different parasites. Additionally, bee abundance was more consistently associated with increased parasite prevalence, providing evidence of amplification. Floral abundance was only associated with lower Apicystis spp. prevalence. Across all parasite models, however, the R2 values were <20%, indicating that additional factors shape bee communities beyond those we examined. Offspring production was positively related to floral diversity but not to parasite prevalence. Our results suggest that managing floral diversity is critical to enhancing the value of these landscapes for wild bee communities, both directly through promoting bee diversity and reproduction, and indirectly through facilitating parasite dilution. [ABSTRACT FROM AUTHOR]

Currently, only Apis mellifera is used in environmental regulation to evaluate the hazard of pesticides to pollinators. The low representativeness of pollinators and bee diversity in this approach may result in insufficient protection for the wild species. This scenario is intensified in tropical environments, where little is known about the effects of pesticides on solitary bees. We aimed to calculate the medium lethal dose (LD50) and medium lethal concentration (LC50) of the insecticide dimethoate in the Neotropical solitary bee Centris analis, a cavity‐nesting, oil‐collecting bee distributed from Brazil to Mexico. Males and females of C. analis were exposed orally to dimethoate for 48 h under laboratory conditions. Lethality was assessed every 24 h until 144 h after the beginning of the test. After the LD50 calculation, we compared the value with available LD50 values in the literature of other bee species using the species sensitivity distribution curve. In 48 h of exposure, males showed an LD50 value 1.33 times lower than females (32.78 and 43.84 ng active ingredient/bee, respectively). Centris analis was more sensitive to dimethoate than the model species A. mellifera and the solitary bee from temperate zones, Osmia lignaria. However, on a body weight basis, C. analis and A. mellifera had similar LD50 values. Ours is the first study that calculated an LD50 for a Neotropical solitary bee. Besides, the results are of crucial importance for a better understanding of the effects of pesticides on the tropical bee fauna and will help to improve the risk assessment of pesticides to bees under tropical conditions, giving attention to wild species, which are commonly neglected. Environ Toxicol Chem 2023;42:2758–2767. © 2023 SETAC [ABSTRACT FROM AUTHOR]