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The honey bee Apis mellifera is a model organism for sociogenomics and one of the most important managed pollinators. High mortalities experienced by honey bee colonies over the past several decades are expected to have a substantive effect on crop pollination and global food security. These threats and the availability of a growing number of genomic resources for the honey bee have motivated research on how genetics and genomics can be practically applied to manage bee health. The authors review 3 such applications: (1) Certification of bee lineages using single-polymorphism markers; (2) breeding bees using marker-assisted selection; (3) diagnosing honey bee stressors using biomarkers.

The dependence of commercial crops on pollinators is closely related to their reproductive strategies and has direct impacts on production yields. Fruit production of Averrhoa carambola, the star fruit, is highly dependent on bee pollination. This distylous species may exhibit monomorphism associated with self-compatibility, a condition that may influence its degree of dependence on pollinators for fruit set. We evaluated the floral morphology and mating system of A. carambola and their relationships with pollinator dependence in an apparently pin-monomorphic orchard to address the following questions: Is the orchard indeed pin-monomorphic? Is the orchard self-compatible? Are pollination services sufficient to reach maximum productivity? Is fruit set related to the number of visits? We investigated floral morphometrics, mating system, and pollination following standard methods of plant reproduction research. The orchard exhibited pin-monomorphism and self-compatibility. Herkogamy strongly impaired spontaneous self-pollination, emphasizing the relevance of pollinators to crop yield. Considering that Apis mellifera was the only pollinator observed, and that the orchard showed pollen limitation, we recommend the implementation of pollinator management strategies. Additional studies will be needed to assess if the atypical distyly observed here occurs in other situations.

Pollinators support the production of the leading food crops worldwide. Organophosphates are a heavily used group of insecticides that pollinators can be exposed to, especially during crop pollination. Exposure to lethal or sublethal doses can impair fitness of wild and managed bees, risking pollination quality and food security. Here we report a low-cost, scalable in vivo detoxification strategy for organophosphate insecticides involving encapsulation of phosphotriesterase (OPT) in pollen-inspired microparticles (PIMs). We developed uniform and consumable PIMs capable of loading OPT at 90% efficiency and protecting OPT from degradation in the pH of a bee gut. Microcolonies of Bombus impatiens fed malathion-contaminated pollen patties demonstrated 100% survival when fed OPT−PIMs but 0% survival with OPT alone, or with plain sucrose within five and four days, respectively. Thus, the detrimental effects of malathion were eliminated when bees consumed OPT−PIMs. This design presents a versatile treatment that can be integrated into supplemental feeds such as pollen patties or dietary syrup for managed pollinators to reduce risk of organophosphate insecticides. Organophosphate insecticides are highly toxic to pollinators. Bumblebees fed pollen patties contaminated with phosphotriesterase insecticide encapsulated in pollen-inspired microparticles demonstrated 100% survival.

Global environmental change is critically endangering plant-pollinator interactions, as shown in this issue of One Earth by Huang et al., who combine phenomenological models with empirical plant-pollinator networks. Losses of pollination services in agricultural landscapes also endanger global food security but meeting the challenge of better understanding and sustaining crop pollination needs new approaches and policies.

Super-generalism is a pollinator trait where species obtain floral resources from a very wide range of plant species. Theoretical and empirical studies suggest that on islands with low pollinator diversity, such pollinators should evolve to exploit a very wide range of floral morphologies. Super-generalism has implications not only for securing pollination network stability, but also for the invasibility of potential weeds that require specialist pollinators in their original ranges. Here we expand earlier studies on bees in Fiji to include a wider range of bee-plant interactions for bees that have been recently introduced into Fiji as well as the endemic Fijian halictine bee, Homalictus fijiensis. Our data show that the endemic Fijian bee has a much wider range of floral hosts than introduced bees, and this extends to pollen larceny of solanoid plant species that are usually buzz pollinated. Importantly, solanoid plants were not visited by introduced bee species, including the honeybee Apis mellifera, which is usually regarded as a super-generalist. Our findings are important because they add critical support to the hypothesis that super-generalism evolves in insular ecosystems with low pollinator diversity and that this may make such ecosystems vulnerable to invasion by exotic weeds. However, insular super-generalists may also have potential to stabilize plant-pollinator networks and may also be effective pollinators for exotic crop species, and this needs to be further explored in agricultural settings. Refereed/Peer-reviewed

International audience; AbstractThe need for basic information on tropical crop pollinators remains a key priority. Here, we used a dataset on Brazilian bee-crop interactions to determine important bee species for crop pollination and discuss their management in Brazilian croplands. We developed an analytical approach to select key bee species and genera from datasets based on different criteria, selecting only interactions reported as effective pollination events. Data on pollination included 261 records of unique crop-pollinator interaction, 144 bee species, and 23 crops. Despite the importance of social species, solitary bees accounted for 56% of the observed interactions. Of the 14 most important species, eight are solitary and six are social. A few of the selected species are already reared in Brazil, e.g., honeybees and some stingless bees, but practical knowledge on their management for crop pollination is poorly disseminated among farmers, hindering such an application.

Non-bee insects have been identified as important crop pollinators globally. However, strategies to protect pollinators and enhance crop pollination usually focus on supporting bees. This study examined the effects of landscape structure, location within field, and floral resources on pollinators’ visits on mass-flowering caraway (Carum carvi L.) in boreal farmland, and the effects of the visits on caraway yield. Pollinator visits on caraway flowers were monitored and caraway yield measured in 30 fields at landscapes ranging from field-dominated to forest-dominated landscapes. Hoverflies were the most abundant flower-visitors of caraway, followed by honeybees. Hoverflies and other flies made more flower visits on caraway than all bee species combined. Pollinator groups differed in their responses to landscape and local factors. Flies were most abundant near field edges and in landscapes with high forest cover. Non-syrphid flies and solitary bees responded positively to the cover of flowering herbs in the adjacent field margins. Flower visits by honeybees, instead, were positively related to the flowering crop cover in the study fields. Caraway seed yield increased with increasing number of flower visits by honeybees, hoverflies and all pollinators together. Pollinator exclusion reduced caraway fruit set (i.e. the number of fruits per flower) by 13% and seed yield by 40%. Our study is the first to report the high importance of flies to crop pollination in boreal farmland, where caraway is an important export crop. The results highlight the need of taking flies and their habitat requirements into account when developing strategies to enhance crop pollination. Highlights • Hoverflies were the most frequent flower-visitors on caraway, followed by honeybees. • Flies made more flower visits than all bee species combined. • Flies were abundant near field edges and in landscapes with high forest cover. • Honeybees responded positively to the flowering crop cover. • Flower visits by both honeybees and hoverflies increased caraway yield.

Significance Environmental damage from insecticide overuse is a major concern, particularly for conservation of “good” insects such as pollinators that ensure stable production of food crops like fruits and vegetables. However, insecticides are also necessary for farmers to manage “bad” insects (i.e., pests), and thus, a more holistic view of crop management needs to account for the proper balance between the beneficial and detrimental aspects of pesticides. Here, we used multiyear field experiments with a paired corn–watermelon cropping system to show that insecticide use can be dramatically reduced (by ∼95%) while maintaining or even increasing yields through the conservation of wild bees as crop pollinators. These data demonstrate that food production and ecosystem sustainability are not necessarily conflicting goals., Pest management practices in modern industrial agriculture have increasingly relied on insurance-based insecticides such as seed treatments that are poorly correlated with pest density or crop damage. This approach, combined with high invertebrate toxicity for newer products like neonicotinoids, makes it challenging to conserve beneficial insects and the services that they provide. We used a 4-y experiment using commercial-scale fields replicated across multiple sites in the midwestern United States to evaluate the consequences of adopting integrated pest management (IPM) using pest thresholds compared with standard conventional management (CM). To do so, we employed a systems approach that integrated coproduction of a regionally dominant row crop (corn) with a pollinator-dependent specialty crop (watermelon). Pest populations, pollination rates, crop yields, and system profitability were measured. Despite higher pest densities and/or damage in both crops, IPM-managed pests rarely reached economic thresholds, resulting in 95% lower insecticide use (97 versus 4 treatments in CM and IPM, respectively, across all sites, crops, and years). In IPM corn, the absence of a neonicotinoid seed treatment had no impact on yields, whereas IPM watermelon experienced a 129% increase in flower visitation rate by pollinators, resulting in 26% higher yields. The pollinator-enhancement effect under IPM management was mediated entirely by wild bees; foraging by managed honey bees was unaffected by treatments and, overall, did not correlate with crop yield. This proof-of-concept experiment mimicking on-farm practices illustrates that cropping systems in major agricultural commodities can be redesigned via IPM to exploit ecosystem services without compromising, and in some cases increasing, yields.

Premise Many animals provide ecosystem services in the form of pollination, including honeybees which have become globally dominant floral visitors. A rich literature documents considerable variation in single visit pollination effectiveness, but this literature has yet to be extensively synthesized to address whether honeybees are effective pollinators. Methods We conducted a hierarchical meta-analysis of 168 studies and extracted 1564 single visit effectiveness (SVE) measures for 240 plant species. We paired SVE data with visitation frequency data for 69 of these studies. We used these data to ask: 1) Do honeybees (Apis mellifera) and other floral visitors differ in their SVE?; 2) To what extent do plant and pollinator attributes predict differences in SVE between honeybees and other visitors?; and 3) Is there a correlation between visitation frequency and SVE? Key results Honeybees were significantly less effective than the most effective non-honeybee pollinators but as effective as the average pollinator. The type of pollinator moderated these effects. Honeybees were less effective compared to the most effective and average bird and bee pollinators but were as effective as other taxa. Visitation frequency and SVE were positively correlated, but this trend was largely driven by data from communities where honeybees were absent. Conclusions Although high visitation frequencies make honeybees important pollinators, they were less effective than the average bee and rarely the most effective pollinator of the plants they visit. As such, honeybees may be imperfect substitutes for the loss of wild pollinators and safeguarding pollination will benefit from conservation of non-honeybee taxa. This article is protected by copyright. All rights reserved.

Bees are critical for crop pollination, but there is limited information on levels and sources of pesticide exposure in commercial agriculture. We collected pollen from foraging honey bees and bumble bees returning to colonies placed in blooming blueberry fields with different management approaches (conventional, organic, unmanaged) and located across different landscape settings to determine how these factors affect pesticide exposure. We also identified the pollen and analyzed whether pesticide exposure was correlated with corbicular load composition. Across 188 samples collected in 2 years, we detected 80 of the 259 pesticide active ingredients (AIs) screened for using a modified QuEChERS method. Detections included 28 fungicides, 26 insecticides, and 21 herbicides. All samples contained pesticides (mean = 22 AIs per pollen sample), with pollen collected from bees on conventional fields having significantly higher average concentrations (2019 mean = 882.0 ppb) than those on unmanaged fields (2019 mean = 279.6 ppb). Pollen collected by honey bees had more AIs than pollen collected by bumble bees (mean = 35 vs. 19 AIs detected at each farm, respectively), whereas samples from bumble bees had higher average concentrations, likely reflecting differences in foraging behavior. Blueberry pollen was more common in pollen samples collected by bumble bees (25.9% per sample) than honey bees (1.8%), though pesticide concentrations were only correlated with blueberry pollen for honey bees. Pollen collected at farms with more blueberry in the surrounding landscape had higher pesticide concentrations, mostly AIs applied for control of blueberry pathogens and pests during bloom. However, for honey bees, the majority of AIs detected at each farm are not registered for use on blueberry at any time (55.2% of AIs detected), including several highly toxic insecticides. These AIs therefore came from outside the fields and farms they are expected to pollinate. For bumble bees, the majority of AIs detected in their pollen are registered for use on blueberry during bloom (56.9% of AIs detected), though far fewer AIs were sprayed at the focal farm (16.7%). Our results highlight the need for integrated farm and landscape-scale stewardship of pesticides to reduce exposure to pollinators during crop pollination.

The importance of wild bees for crop pollination is well established, but less is known about which species contribute to service delivery to inform agricultural management, monitoring and conservation. Using sites in Great Britain as a case study, we use a novel qualitative approach combining ecological information and field survey data to establish a national list of crop pollinating bees for four economically important crops (apple, field bean, oilseed rape and strawberry). A traits data base was used to establish potential pollinators, and combined with field data to identify both dominant crop flower visiting bee species and other species that could be important crop pollinators, but which are not presently sampled in large numbers on crops flowers. Whilst we found evidence that a small number of common, generalist species make a disproportionate contribution to flower visits, many more species were identified as potential pollinators, including rare and specialist species. Furthermore, we found evidence of substantial variation in the bee communities of different crops. Establishing a national list of crop pollinators is important for practitioners and policy makers, allowing targeted management approaches for improved ecosystem services, conservation and species monitoring. Data can be used to make recommendations about how pollinator diversity could be promoted in agricultural landscapes. Our results suggest agri-environment schemes need to support a higher diversity of species than at present, notably of solitary bees. Management would also benefit from targeting specific species to enhance crop pollination services to particular crops. Whilst our study is focused upon Great Britain, our methodology can easily be applied to other countries, crops and groups of pollinating insects., SCOPUS: ar.j, info:eu-repo/semantics/published

The entomophilous pollination niche (abundance, phenotypic traits, foraging behaviours and environmental tolerances of insect pollinators) helps to understand and better manage crop polli-nation. We apply this niche approach to assess how an entomophilous crop (blueberry, Vaccinium ashei) can be expanded into new territories (i.e., northern Spain) far from their original area of domestication (North America). Insect visits to blueberry flowers were monitored in a plantation on 12 different days, at 8 different times during day and covering various weather conditions. Abundance, visitation rate, pollen gathering behaviour, and frequency of inter-plant and inter-row movements were recorded. The pollinator assemblage was basically composed of one managed honeybee species (50.8% of visits) and three native bumblebee species (48.3%). There was a marked pattern of seasonal segregation throughout bloom, with bumblebees dominating the early bloom and honeybee the late bloom. Pollinators also segregated along gradients of daily temperature and relative humidity. Finally, the two pollinator types differed in foraging behaviour, with bumblebees having a visitation rate double that of honeybee, collecting pollen more frequently and changing plant and row more frequently. The spatio-temporal and functional complementarity between honeybee and bumblebees suggested here encourages the consideration of an integrated crop pollination strategy for blueberries, based on the concurrence of both wild and managed bees., The study was supported by grants INIA-RTA2013-00139-C03-01 and INIA-RTA2017-00051-C02-01 (Ministerio de Economía, Industria y Competitividad (MinECo) and Fondo Europeo de Desarrollo Regional) to MM.

Insecticide use and insufficient forage are two of the leading stressors to pollinators in agroecosystems. While these factors have been well studied individually, the experimental designs do not reflect real-world conditions where insecticide exposure and lack of forage occur simultaneously and could interactively suppress pollinator health. Using outdoor enclosures, we tested the effects of insecticides (imidacloprid + lambda-cyhalothrin) and non-crop forage (clover) in a factorial design, measuring the survival, behaviour and performance of bumblebees ( Bombus impatiens ), as well as pollination of the focal crop, watermelon. Colony survival was synergistically reduced to 17% in watermelon alone + insecticides (survival was 100% in all other treatments). However, behavioural shifts in foraging were mainly owing to insecticides (e.g. 95% reduced visitation rate to watermelon flowers), while impacts on hive performance were primarily driven by clover presence (e.g. 374% increase in the number of live eggs). Insecticide-mediated reductions in foraging decreased crop pollination (fruit set) by 32%. Altogether, these data indicate that both insecticides and non-crop forage play integral roles in shaping pollinator health in agricultural landscapes, but the relative importance and interaction of these two factors depend on which aspect of ‘health’ is being considered.

We evaluated the capacity of selected plants, sown along a processing tomato field margin in central Greece and natural vegetation, to attract beneficial and Hymenoptera pollinating insects and questioned whether they can distract pollinators from crop flowers. Measurements of flower cover and attracted pollinators and beneficial arthropods were recorded from early-May to mid-July, during the cultivation period of the crop. Flower cover was higher in the sown mixtures compared to natural vegetation and was positively correlated with the number of attracted pollinators. The sown Glebionis coronaria, Coriandrum sativum, Anethum graveolens, and Fagopyrum esculentum attracted mainly wild bees, which were the most abundant pollinating insects. In the natural vegetation, Rapistrum rugosum attracted mainly honeybees, while Asteraceae, Convolvulaceae, and Apiaceae species attracted wild bees. Beneficial arthropod abundance and diversity were higher in the sown mixture. Tomato flowers were visited by a small number of wild bees. Their number was not affected by the distance from the field margin, indicating no distraction effect from the sown or natural vegetation flowering plants. Our results suggest that selected flowering plants can improve the field margin habitats for pollinating insects and beneficial arthropods, but more work is needed to elucidate the effect on crop pollination.

Many modern crop varieties rely on animal pollination to set fruit and seeds. Intensive crop plantations usually do not provide suitable habitats for pollinators so crop yield may depend on the surrounding vegetation to maintain pollination services. However, little is known about the effect of pollinator‐mediated interactions among co‐flowering plants on crop yield or the underlying mechanisms. Plant reproductive success is complex, involving several pre‐ and post‐pollination events; however, the current literature has mainly focused on pre‐pollination events in natural plant communities. We assessed pollinator sharing and the contribution to pollinator diet in a community of wild and cultivated plants that co‐flower with a focal papaya plantation. In addition, we assessed heterospecific pollen transfer to the stigmatic loads of papaya and its effect on fruit and seed production. We found that papaya shared at least one pollinator species with the majority of the co‐flowering plants. Despite this, heterospecific pollen transfer in cultivated papaya was low in open‐pollinated flowers. Hand‐pollination experiments suggest that heterospecific pollen transfer has no negative effect on fruit production or weight, but does reduce seed production. These results suggest that co‐flowering plants offer valuable floral resources to pollinators that are shared with cultivated papaya with little or no cost in terms of heterospecific pollen transfer. Although HP reduced seed production, a reduced number of seeds per se are not negative, given that from an agronomic perspective the number of seeds does not affect the monetary value of the papaya fruit.

Introduction. The species and functional diversity of pollinators are important components for the reproduction of cultivated plants. More information is necessary about this diversity and its geographical variation in crops such as Cucurbita pepo, one of the most important crops in global agriculture. Objective. To describe the diversity and geographic variation of the community of bees that visit C. pepo crops in Costa Rica and their foraging s Introduction: The species and functional diversity of pollinators are important components for the reproduction of cultivated plants. More information is necessary about this diversity and its geographical variation in crops such as Cucurbita pepo, an important crop in global agriculture. Objective: To describe the taxonomic diversity, geographic variation and foraging patterns of the community of bees that visit C. pepo crops in Costa Rica. Methods: Squash fields were visited at 11 locations within three geographic regions of the country, where the groups of bees and their relative frequency were determined. Through video recordings, information was obtained on their behavior at two locations. Results: A minimum of 27 species belonging to 19 genera and 2 families of bees were found. Three species were dominant in 10 localities (Eucera limitaris, Apis mellifera and Trigona corvina). Altitude reduces bee diversity due to the dominance of Bombus ephipiatus in high regions. Two genera of halictids (Megalopta and Caenaugochlora) that are rarely reported in this crop were frequently observed. Trigona bees dominated among the flowers later in the morning, lacerating nectary holes to facilitate nectar collection. Conclusions: Squash fields in Costa Rica are visited by a highly diverse bee community, which may ensure pollination via complementarity in the face of spatial or seasonal changes in environmental conditions. chedule and intrafloral behavior. Methods. Squash fields were visited at 12 locations within three geographic regions of the country, where the groups of bees and their relative frequency were determined. Through video recordings, information was obtained on their behavior at two locations. Results. A minimum of 27 species belonging to 19 genera and 2 families of bees were found. Three species were dominant at many localities (Eucera limitaris, Apis mellifera and Trigona corvina). Altitude causes drastic changes in their diversity and composition. Two genera of halictids (Megalopta and Caenaugochlora) that are rarely reported in this crop were frequently observed. Trigona bees dominated among the flowers later in the morning. Conclusions. Squash fields in Costa Rica are visited by a highly diverse bee community, which may ensure pollination via complementarity in the face of spatial or seasonal changes in environmental conditions. Introducción. Dada la importancia del componente diversidad para la polinización de plantas cultivadas, es necesario obtener más información de esta diversidad y su variación geográfica en cultivos como Cucurbita pepo, uno de los cultivos más importantes de la agricultura centroamericana. Objetivo: Describir la diversidad y la variación geográfica de la comunidad de abejas que visitan este cultivo en Costa Rica, y algunos aspectos de sus patrones de búsqueda de alimento. Métodos: Se visitaron cultivos de C. pepo en 11 localidades dentro de tres regiones geográficas de Costa Rica, donde se determinó los grupos de abejas y su frecuencia relativa. Por medio de grabaciones de video se registró el comportamiento de cada grupo en dos localidades. Resultados: Fueron encontradas un mínimo de 27 especies pertenecientes a 19 géneros y 2 familias de abejas. Tres especies son dominantes en 10 localidades (Eucera limitaris, Apis mellifera y Trigona corvina). La altitud reduce la diversidad de abejas debido a la dominancia de Bombus ephipiatus en regiones altas. Se observaron dos géneros de halíctidos (Megalopta y Caenaugochlora) no previamente reportados en este cultivo. Abejas Trigona dominan las flores en horarios más tardíos de la mañana, donde algunas veces muerden los orificios de los nectarios para facilitar la recolecta de néctar. Conclusiones: La diversidad de abejas que visitan C. pepo en Costa Rica parece asegurar su polinización ante cambios espaciales o estacionales en condiciones ambientales.

Pollinator refuges such as wildflower strips are planted on farms with the goals of mitigating wild pollinator declines and promoting crop pollination services. It is unclear, however, whether or how these goals are impacted by managed honey bee (Apis mellifera L.) hives on farms. We examined how wildflower strips and honey bee hives and/or their interaction influence wild bee communities and the fruit count of two pollinator-dependent crops across 21 farms in the Mid-Atlantic U.S. Although wild bee species richness increased with bloom density within wildflower strips, populations did not differ significantly between farms with and without them whereas fruit counts in both crops increased on farms with wildflower strips during one of 2 years. By contrast, wild bee abundance decreased by 48%, species richness by 20%, and strawberry fruit count by 18% across all farm with honey bee hives regardless of wildflower strip presence, and winter squash fruit count was consistently lower on farms with wildflower strips with hives as well. This work demonstrates that honey bee hives could detrimentally affect fruit count and wild bee populations on farms, and that benefits conferred by wildflower strips might not offset these negative impacts. Keeping honey bee hives on farms with wildflower strips could reduce conservation and pollination services. NIFA Agroecosystem Management award [2015-67019-23215] We would like to thank the collaborating farms. Bob Glennon and Velva Groover helped establish wildflower strips; Roy Flanagan, Jane Lassiter, and Michael Sigrist helped locate collaborating farms; Jayesh Samtani provided strawberry plants; Erica Head, Monique Ayers, Sarah Head, and Courtney Floyd assisted with field work; and Sam Droege provided bee species determinations. Lisa Horth and Heather Grab provided insightful comments on the manuscript. Funds were provided by a NIFA Agroecosystem Management award to M. O'Rourke number 2015-67019-23215. The United States Department of Agriculture is an equal opportunity provider and employer. The use of trade names or commercial products in this publication is to provide information for the and does not imply recommendation or endorsement by the USDA. We have no conflicts of interest to report.

Global biodiversity is declining under pressure of agricultural intensification and land-use change. Two-thirds of the agricultural lands is directly or indirectly devoted to the production of animal products. Replacing animal-based proteins by plant-based proteins can be an important step to a more sustainable agricultural system. Lupins (Lupinus sp.) are promising crop species due to a high protein content of up to 40 %, but crop yields are unstable in both quantity and quality. This might be due to a lack of effective pollinators, but the contribution of insect pollination to lupin crop yield is unknown. Here we studied for five varieties of two common lupin crop species (L. albus and L. angustifolius) which pollinators visit lupin flowers, whether this depends on nectar production, and what the contribution of insect pollination is to crop yield. We used a semi-experimental setup and placed bagged and open-pollinated plants in pots along an expected gradient of insect visitors and determined several yield parameters. We recorded 1355 pollinator visits of only eight bee species. None of the varieties tested produced nectar. Compared to bagged plants, protein yield increase of open-pollinated plants ranged from 3 to 11% depending on variety. Yield of open-pollinated plants was only consistently related to visitation of the large-bodied buff-tailed bumblebee (B. terrestris group; 59 % of all pollinators) with impact on seed set related yield parameters (number of seeds and pods) being generally larger than on seed filling related yield parameters (g/plant). Within the observed range, higher visitation rate of buff-tailed bumblebees increased protein yield of open-pollinated plants with 10–40 %. Visitation rates of the smaller common carder bee (B. pascuorum; 33 % of all pollinators), or all pollinators combined, were not significantly related to protein crop yield. This could indicate that only relatively large species are effective lupin pollinators. Lupins are generally considered self-pollinating, and therefore growers do not actively manage for insect pollination. Our results show that insect pollination, and in particular buff-tailed bumblebees, can contribute substantially to the crop yield, which suggests that management aimed at enhancing effective pollinator species can help to make lupin crop cultivation more profitable. Amongst others, such management should make sure that ample nectar is available in the surroundings of lupin crops, as lupin does not produce nectar.

Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Aizen, Marcelo A. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Arbetman, Marina P. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Arbetman, Marina P. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Chacoff, Natacha P. Universidad Nacional de Tucumán. Instituto de Ecología Regional; Argentina. Fil: Chalcoff, Vanina R. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Chalcoff, Vanina R. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Feinsinger, Peter. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Centro de Estudio y Aplicación del Ciclo de Indagación; Argentina. Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garibaldi, Lucas A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Harder, Lawrence D. University of Calgary. Department of Biological Sciences; Canada. Fil: Morales, Carolina L. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Morales, Carolina L. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Sáez, Agustín. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Sáez, Agustín. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Vanbergen, Adam J. Université de Bourgogne Franche-Comté. AgroSup Dijon; Francia. Increasing honey demand and global coverage of pollinator-dependent crops within the context of global pollinator declines have accelerated international trade in managed bees. Bee introductions into agricultural landscapes outside their native ranges have triggered noteworthy invasions, especially of the African honey bee in the Americas and the European bumble bee Bombus terrestris in southern South America, New Zealand, Tasmania, and Japan. Such invasions have displaced native bees via competition, pathogen transmission, and invaders' capacity to exploit anthropogenic landscapes. At high abundance, invasive bees can degrade the mutualistic nature of many of the flower-pollinator interactions they usurp, either directly by affecting flower performance or indirectly by reducing the pollination effectiveness of other flower visitors, with negative consequences for crop pollination and yield. We illustrate such effects with empirical examples, focusing particularly on interactions in the Americas between B. terrestris and raspberry and between the African honey bee and coffee. Despite high bee abundance and flower visitation in crops, theoretical and empirical evidence suggests that agricultural landscapes of pollinator-dependent crops dominated by invasive bees will be less productive than landscapes with more diverse pollinator assemblages. Safeguarding future crop yield and aiding the transition to more sustainable agricultural landscapes and practices require we address this impact of invasive bees. Actions include tighter regulation of the trade in bees to discourage further invasions, reducing invasive bee densities and dominance, and active enhancement of ecological infrastructure from field to landscape scales to promote wild bee abundance and diversity for sustained delivery of crop pollination services.

Pollination by wild pollinators is a key ecosystem service threatened by anthropogenic-induced land-use change. The proximity to natural habitat has previously been shown to positively affect pollinator communities and improve crop yield and quality but empirical evidence is limited from most parts of the World. Here, across six farms in Southern Thailand, we investigated the significance of landscape-level effects of natural habitat (proportion of and distance to evergreen forest) on both visitation rate and richness of pollinators as well as fruit set of guava (Psidium guajava L.), a local economically-important crop in the tropics. Overall, the most abundant pollinator was the Asian honey bee Apis cerana (39% of all visits) and different species of stingless bees (37%). We found that pollinator richness was unrelated to the proportion and distance to evergreen forest, however, the proportion of forest within a 1, 5 and 10 km radius had a significant positive impact on visitation rate of wild pollinators. Still, neither the various forest parameters nor pollinator visitation rate showed a significant impact on fruit set of guava, perhaps because guava self-pollinates. This illustrates that landscape-level degradation of natural habitat may negatively impact pollinator communities without diminishing the crop yield of the farmers.

We investigated the foraging pattern of A. mellifera in five commercial types of melon (Yellow, Cantaloupe, Charentais, Galia and Piel de Sapo) grown side by side. We also observed if this bee species can discriminate between flowers of the five melon types and if it shows preference for flowers of any of them. Results showed that the bees visit flowers of all types of melon throughout the day collecting pollen and nectar in similar foraging patterns. However, they visited significantly more flowers of the Cantaloupe type followed by the types Piel de Sapo and Yellow, while the melons type Galia and Charentais were the least visited by the bees. This behavior has implications for the use of A. mellifera for melon pollination, requiring that the bees be managed according to the type of melon cultivated. It also highlights the need to find out what makes flowers of some melon types to be more visited than others in order to select within the less visited types of melon for cultivars more attractive to the bees. RESUMO Investigamos o padrão de forrageamento de A. mellifera em cinco tipos comerciais de melão (Amarelo, Cantaloupe, Charentais, Gália e Pele de Sapo) cultivados lado a lado. Observamos também se esta espécie de abelha pode discriminar entre flores dos cinco tipos de melão e se mostra preferência por flores de qualquer um deles. Os resultados mostraram que as abelhas visitam flores de todos os tipos de melão ao longo do dia coletando pólen e néctar em padrões similares de forrageamento. No entanto, elas visitaram significativamente mais flores do tipo Cantaloupe, seguido dos tipos Pele de Sapo e Amarelo, enquanto os melões tipo Gália e Charentais foram os menos visitados pelas abelhas. Este comportamento tem implicações para o uso de A. mellifera na polinização do melão, exigindo que as abelhas sejam manejadas de acordo com o tipo de melão cultivado. Ele também destaca a necessidade de descobrir o que faz com que as flores de alguns tipos de melão sejam mais visitadas do que de outros, a fim de selecionar, dentro dos tipos de melão menos visitados, cultivares mais atraentes para as abelhas.

Fil: Pérez Méndez, Néstor. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Pérez Méndez, Néstor. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Pérez Méndez, Néstor. Institut de Recerca i Tecnologia Agroalimentàries. Estació Experimental de l'Ebre; España. Fil: Andersson, Georg K. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Andersson, Georg K. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Andersson, Georg K. Lund University. Centre for Environmental and Climate Research; Suecia. Fil: Requier, Fabrice. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Requier, Fabrice. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Requier, Fabrice. Université Paris-Sud. Evolution Génome Comportement et Ecologie; Francia. Fil: Hipólito, Juliana. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Hipólito, Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Hipólito, Juliana. Instituto Nacional de Pesquisas da Amazônia; Brasil. Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Aizen, Marcelo A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Morales, Carolina. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Morales, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: García, Nancy. Agencia de desarrollo económico del Neuquén. Centro Pyme Adeneu; Argentina. Fil: Gennari, Gerardo P. Instituto Nacional de Tecnología Agropecuaria. Estación Experimental Agropecuaria Famaillá; Argentina. Fil: Garibaldi, Lucas Alejandro. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Garibaldi, Lucas Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. The alarming loss of pollinator diversity world‐wide can reduce the productivity of pollinator‐dependent crops, which could have economic impacts. However, it is unclear to what extent the loss of a key native pollinator species affects crop production and farmer's profits. By experimentally manipulating the presence of colonies of a native bumblebee species Bombus pauloensis in eight apple orchards in South Argentina, we evaluated the impact of losing natural populations of a key native pollinator group on (a) crop yield, (b) pollination quality, and (c) farmer's profit. To do so, we performed a factorial experiment of pollinator exclusion (yes/no) and hand pollination (yes/no). Our results showed that biotic pollination increased ripe fruit set by 13% when compared to non‐biotic pollination. Additionally, fruit set and the number of fruits per apple tree was reduced by less than a half in those orchards where bumblebees were absent, even when honeybees were present at high densities. Consequently, farmer's profit was 2.4‐fold lower in farms lacking bumblebees than in farms hosting both pollinator species. The pollination experiment further suggested that the benefits of bumblebees could be mediated by improved pollen quality rather than quantity. Synthesis and applications. This study highlights the pervasive consequences of losing key pollinator functional groups, such as bumblebees, for apple production and local economies. Adopting pollinator‐friendly practices such as minimizing the use of synthetic inputs or restoring/maintaining semi‐natural habitats at farm and landscape scales, will have the double advantage of promoting biodiversity conservation, and increasing crop productivity and profitability for local farmers. Yet because the implementation of these practices can take time to deliver results, the management of native pollinator species can be a provisional complementary strategy to increase economic profitability of apple growers in the short term. La alarmante pérdida de polinizadores que acontece a escala global puede reducir la productividad y el potencial económico de muchos cultivos entomófilos (p.ej. frutales). Sin embargo, aún no está claro hasta qué punto la pérdida de una única especie (o grupo funcional) puede afectar al rendimiento del cultivo y al beneficio económico del agricultor. Se manipuló experimentalmente la presencia de una especie de abejorro nativo Bombus pauloensis en ocho fincas de manzano en el sur de Argentina, para evaluar cómo la pérdida de las poblaciones nativas de este grupo de polinizadores (abejorros) afecta a (a) el rendimiento del cultivo, (b) a la calidad de la polinización y (c) al rendimiento económico del cultivo. Para ello, llevamos a cabo además un experimento factorial de exclusión de polinizadores (sí/no) y suplemento manual de polen (sí/no). Nuestros resultados muestran que la polinización biótica, es decir mediada por polinizadores, incrementó el cuajado de frutos maduros en un 13% respecto a la polinización abiótica (sin polinizadores). Además, el cuajado y el número de frutos por manzano se redujo a más de la mitad en aquellas fincas donde, a pesar de que la abeja de la miel estaba presente en altas densidades, el abejorro nativo estaba ausente. Como consecuencia, el beneficio económico para el agricultor en estas fincas fue 2.4 veces menor que en aquellas donde la abeja de la miel y el abejorro nativo estaban presentes simultáneamente. Nuestro experimento sugiere que la mejora del rendimiento aportada por los abejorros nativos está mediada por una mejora en la calidad del polen más que por un incremento en la cantidad. Síntesis y aplicaciones. Este estudio muestra las consecuencias negativas que van emparejadas a la pérdida de grupos de polinizadores clave, como los abejorros, en la producción de manzana y en el beneficio económico del agricultor. La adopción de prácticas agrícolas amigables con los polinizadores, como la reducción de agroquímicos o la restauración y mantenimiento de hábitats seminaturales a escala local y a escala de paisaje, se espera que tenga la doble ventaja de promover, por un lado, la conservación de la biodiversidad y, por otro, incrementar la productividad y el rendimiento económico para los productores. Dado que estas prácticas pueden tardar un tiempo en dar resultados, el manejo de especies nativas de polinizadores puede ser una estrategia provisional y complementaria para reducir, a corto plazo, el impacto económico para el agricultor.

Chamer, Ana María. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica General. Buenos Aires, Argentina. - Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica Sistemática. Buenos Aires, Argentina. Medan, Diego. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica General. Buenos Aires, Argentina. - Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica Sistemática. Buenos Aires, Argentina. - CONICET. Buenos Aires, Argentina. Montaldo, Norberto Horacio. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica General. Buenos Aires, Argentina. - Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica Sistemática. Buenos Aires, Argentina. Mantese, Anita Ida. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica General. Buenos Aires, Argentina. - Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica Sistemática. Buenos Aires, Argentina. Devoto, Mariano. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica General. Buenos Aires, Argentina. - Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica Sistemática. Buenos Aires, Argentina. - CONICET. Buenos Aires, Argentina. La producción, la calidad y la estabilidad de muchos cultivos, incluido el girasol, aumenta por la presencia de polinizadores que, en su mayoría, nidifican y obtienen recursos florales de los fragmentos de hábitat seminatural presentes en el paisaje. Los objetivos del estudio fueron 1) comprender la interacción del girasol con sus visitantes florales, con especial atención al efecto de la distancia al borde del cultivo, y 2) caracterizar la estructura de la red planta-polinizador, que incluye al girasol, la vegetación acompañante y sus visitantes florales, en el marco de un paisaje de la Región Pampeana sometido a uso agrícola intensivo (Gral. Villegas, provincia de Buenos Aires), donde el cultivo de girasol coexiste con la vegetación espontánea del borde. Entre los principales resultados se destaca, primero, que un grupo de abejas nativas dominó el elenco de visitantes florales; segundo, que la tasa de visita de Apis mellifera al girasol cayó hacia el interior del lote; finalmente, que los recursos florales del borde del cultivo que utilizan los polinizadores nativos son en su mayoría de origen exótico. Además, el enfoque de redes utilizado permitió ver la importancia de la vegetación circundante en el sostenimiento de las poblaciones de polinizadores del cultivo de girasol. En el presente contexto de intensificación del manejo agrícola, con la consiguiente reducción de bordes de cultivo y pérdida generalizada de biodiversidad en agroecosistemas resulta imperativo conocer mejor el valor económico y ecológico de los bordes de cultivo para sostener a los polinizadores y a la fauna benéfica en general. grafs.

The sustainability of agriculture can be improved by integrating management of ecosystem services, such as insect pollination, into farming practices. However, large‐scale adoption of ecosystem services‐based practices in agriculture is lacking, possibly because growers undervalue the benefits of ecosystem services compared to those of conventional management practices. Here we show that, under representative real‐world conditions, pollination and plant quality made similar contributions to marketable seed yield of hybrid leek (Allium porrum). Relative to the median, a 25% improvement of plant quality and pollination increased crop value by an estimated $18 007 and $17 174 ha−1 respectively. Across five crop lines, bumblebees delivered most pollination services, while other wild pollinator groups made less frequent but nevertheless substantial contributions. Honeybees actively managed for pollination services did not make significant contributions. Our results show that wild pollinators are an undervalued agricultural input and managing for enhancing pollinators makes sense economically in high‐revenue insect‐pollinated cropping systems.

Managed and wild pollinators of different functional groups can provide pollination services in agricultural landscapes. These pollinators differ in their resource requirements and response to the amount and arrangement of different habitat types, that is, landscape composition and configuration. Most current approaches to test landscape effects on pollinators and pollination services are either applied to central individual crop fields or other landscape elements but rarely consider that pollinators depend on and make use of multiple habitat elements in an entire landscape. To capture these complex spatial and temporal interactions between different pollinators and habitat elements at the landscape scale, we propose to apply a combination of experimental and observational approaches across multiple habitat types and seasons.

Regional declines in insect pollinators have raised concerns about crop pollination. Many pollinator studies use visitation rate (pollinators/time) as a proxy for the quality of crop pollination. Visitation rate estimates are based on observation durations that vary significantly between studies. How observation duration relates to the accuracy of the visitation rate estimate is, however, unknown. We studied this relationship using six day-long observations (06:00. h-19:00. h) in leek-seed production fields (totalling 78. h). We analysed beyond which point in time observing longer did not significantly improve the accuracy of the visitation rate estimate (minimum observation duration). We furthermore explored the relationship between the minimum observation duration and visitation rate, time of day and temperature. We found that the minimum observation duration (mean. ±. SD: 24. ±. 11.9. min) was significantly related to visitation rate, where the observation time required to obtain accurate estimates decreased with increasing visitation rate. Minimum observation duration varied greatly between days and between fields but not within days. Within days, the visitation rates differed significantly only between the hour-intervals 06:00. h-07:00. h (lowest visitation rate) and 09:00. h-11:00. h (highest rate). Minimum observation duration decreased up to around 22. °C beyond which it remained fairly stable. Surprisingly, even after three day-long observations on the same plant we found new pollinator species visiting the flowers, suggesting that species-richness estimates based on plant observations alone probably underestimate true species richness. Because especially between-day variation in visitation rate on single plants can be large, reliable estimates of the pollinator visitation rate during the plant's flowering time require observations on multiple days. Standardising the number of pollinators rather than the time to observe (standardised pollinator timing approach: time to n-pollinator visits) may provide more consistent accurate assessments of visitation rate, especially for studies that use gradients in visitation rates to examine the contribution of pollinators to crop pollination.

Pollination is an ecosystem service that directly contributes to agricultural production, and can therefore provide a strong incentive to conserve natural habitats that support pollinator populations. However, we have yet to provide consistent and convincing pollination service valuations to effectively slow the conversion of natural habitats. We use coffee in Kodagu, India, to illustrate the uncertainties involved in estimating costs and benefits of pollination services. First, we fully account for the benefits obtained by coffee agroforests that are attributable to pollination from wild bees nesting in forest habitats. Second, we compare these benefits to the opportunity cost of conserving forest habitats and forgoing conversion to coffee production. Throughout, we systematically quantify the uncertainties in our accounting exercise and identify the parameters that contribute most to uncertainty in pollination service valuation. We find the value of pollination services provided by one hectare of forest to be 25% lower than the profits obtained from converting that same surface to coffee production using average values for all parameters. However, our results show this value is not robust to moderate uncertainty in parameter values, particularly that driven by variability in pollinator density. Synthesis and applications. Our findings emphasize the need to develop robust estimates of both value and opportunity costs of pollination services that take into account landscape and management variables. Our analysis contributes to strengthening pollination service arguments used to help stakeholders make informed decisions on land use and conservation practices. © 2019 The Authors. Journal of Applied Ecology © 2019 British Ecological Society

Insect pollination improves the yield and quality of many crops, yet there is increasing evidence of insufficient insect pollinators limiting crop production. Effective Integrated Crop Pollination (ICP) involves adaptable, targeted and cost-effective management of crop pollination and encourages the use of both wild and managed pollinators where appropriate. In this study we investigate how the addition of honeybee hives affects the community of insects visiting oilseed rape, and if hive number and location affect pollinator foraging and oilseed rape pollination in order to provide evidence for effective ICP. We found that introducing hives increased overall flower visitor numbers and altered the pollinator community, which became dominated by honeybees. Furthermore a greater number of hives did not increase bee numbers significantly but did result in honeybees foraging further into fields. The timing of surveys and proximity to the field edge influenced different pollinators in different ways and represents an example of spatial and temporal complementarity. For example dipteran flower visitor numbers declined away from the field edge whereas honeybees peaked at intermediate distances into the field. Furthermore, no significant effects of survey round on wild bees overall was observed but honeybee numbers were relatively lower during peak flowering and dipteran abundance was greater in later survey rounds. Thus combining diverse wild pollinators and managed species for crop pollination buffers spatial and temporal variation in flower visitation. However we found no effect of insect pollination on seed set or yield of oilseed rape in our trial, highlighting the critical need to understand crop demand for insect pollination before investments are made in managing pollination services.

Pollinator biodiversity may benefit crop pollination. Yet benefits in agro-ecosystems may be context-dependent and offset by agronomic or other limiting orchard-specific or tree-specific factors that obscure biodiversity-ecosystem service relationships. To test if crop pollination benefitted from pollinator biodiversity, we sampled local wild bee communities in five organic and five Integrated Pest Management (IPM) apple orchards in Germany and experimentally measured the pollination success of apple flowers, quantified as the number of pollen tubes reaching the base of styles. Using standard statistical modelling approaches for over-dispersed count data, we found little or no effect of wild bee biodiversity on pollination success, irrespectively of farm management (organic versus IPM). There was, however, a positive relationship between the number of pollen tubes in insect-pollinated and pollen-supplemented flowers across trees and orchards, suggesting confounding effects of local tree- or orchard-specific factors limiting pollination success. Using a statistical two-part hurdle model which allowed us to separate (i) the probability of pollination and (ii) the quantity of pollination, we were able to demonstrate that the collective effects of local tree/orchard factors acted as a primary limiting threshold for pollination success. Once the threshold was crossed, the hurdle model demonstrated that increasing wild bee abundance enhanced pollination success of apple trees. We advocate the use of statistical two-part models as a more powerful approach to identifying limiting factors of, and the role of biodiversity in, crop pollination and potentially other ecosystem services in agro-ecosystems.

Simple Summary Methods to rear Osmia bees to pollinate fruit trees have been developed in various parts of the world. These bees are excellent pollinators but evidence that their populations can be sustained in orchards and their use results in increased fruit production is scarce. We released an Osmia cornuta population at one end of an almond orchard. Then, we surveyed the pollinators visiting the almond flowers and measured fruit set in trees located at increasing distances from the nesting stations. We found that fruit production was higher in the trees that received more Osmia visits. Importantly, this result was obtained against a strong background of honeybees, which were 10 times more abundant than Osmia. The Osmia population obtained at the end of the flowering period was 1.28 larger than the population initially released. Our study demonstrates that Osmia populations can be sustained in orchard environments and that even a small population of a highly effective pollinator may have a significant impact on fruit set. Our results are encouraging for the use of Osmia populations and for the implementation of measures to promote wild pollinators in agricultural environments. Abstract Osmia spp. are excellent orchard pollinators but evidence that their populations can be sustained in orchard environments and their use results in increased fruit production is scarce. We released an Osmia cornuta population in an almond orchard and measured its population dynamics, as well as visitation rates and fruit set at increasing distances from the nesting stations. Honeybees were 10 times more abundant than O. cornuta. However, the best models relating fruit set and bee visitation included only O. cornuta visitation, which explained 41% and 40% of the initial and final fruit set. Distance from the nesting stations explained 27.7% and 22.1% of the variability in initial and final fruit set. Of the 198 females released, 99 (54.4%) established and produced an average of 9.15 cells. Female population growth was 1.28. By comparing our results with those of previous O. cornuta studies we identify two important populational bottlenecks (female establishment and male-biased progeny sex ratios). Our study demonstrates that even a small population of a highly effective pollinator may have a significant impact on fruit set. Our results are encouraging for the use of Osmia managed populations and for the implementation of measures to promote wild pollinators in agricultural environments.

The phenology of crop flowering and pollinator reproduction can become asynchronous at the edge of their respective ranges. At a northern site in Peterborough County, Ontario, we evaluated offspring emergence of Cucurbita pollen specialist hoary squash bees (Eucera pruinosa) from nests in enclosures to determine their phenological synchrony with a squash crop (Cucurbita pepo). For the crop, we evaluated the percentage of bees that emerged in time to provide pollination services during the crop pollination window. For the bees, we compared the period when both male and females were present and could mate to the whole crop flowering period. We found that fewer than half the bees had emerged by the time the crop pollination window closed and only 34.1% of the flowering period of the crop could support the reproductive activities of the bees, suggesting that phenological synchrony was imperfect from the perspective of both the crop and the pollinator at this northern site.

Mass-flowering crops (MFCs) are increasingly cultivated and might influence pollinator communities in MFC fields and nearby semi-natural habitats (SNHs). Across six European regions and 2 years, we assessed how landscape-scale cover of MFCs affected pollinator densities in 408 MFC fields and adjacent SNHs. In MFC fields, densities of bumblebees, solitary bees, managed honeybees and hoverflies were negatively related to the cover of MFCs in the landscape. In SNHs, densities of bumblebees declined with increasing cover of MFCs but densities of honeybees increased. The densities of all pollinators were generally unrelated to the cover of SNHs in the landscape. Although MFC fields apparently attracted pollinators from SNHs, in landscapes with large areas of MFCs they became diluted. The resulting lower densities might negatively affect yields of pollinator-dependent crops and the reproductive success of wild plants. An expansion of MFCs needs to be accompanied by pollinator-supporting practices in agricultural landscapes., The study was funded by the EU FP7 project “Status and Trends of European Pollinators” (244 090, www.STEP-project.net) and Biodiversa‐FACCE project “Enhancing biodiversity‐based ecosystem services to crops through optimised densities of green infrastructure in agricultural landscapes” (PCIN‐2014‐048, http://www.cec.lu.se/research/ecodeal). JPGV and MV acknowledge support from the Severo Ochoa Program for Centres of Excellence in R+D+I (SEV‐2012‐0262), and FLORMAS (CGL 2012‐33801). JBW, VJW, SGP and SPMR acknowledge the support of Insect Pollinators Initiative research funded jointly by a grant from BBSRC, Defra, NERC, the Scottish Government and the Wellcome Trust, under the Living with Environmental Change Partnership. HGS and RB were supported by the Swedish Research Council FORMAS. JS and DK were supported by the Dutch Ministry of Economic Affairs (BO‐11‐011.01‐011 and KB‐14‐003‐006), AH and ISD were supported by the DFG Collaborative Research Centre 1047 Insect timing, and ISD and MD through the 2013–2014 BiodivERsA/FACCE – JPI project Ecodeal with national funding from BMBF.

Wild bees are highly valuable pollinators. Along with managed honey bees, they provide a critical ecosystem service by ensuring stable pollination to agriculture and wild plant communities. Increasing concern about the welfare of both wild and managed pollinators, however, has prompted recent calls for national evaluation and action. Here, for the first time to our knowledge, we assess the status and trends of wild bees and their potential impacts on pollination services across the coterminous United States. We use a spatial habitat model, national land-cover data, and carefully quantified expert knowledge to estimate wild bee abundance and associated uncertainty. Between 2008 and 2013, modeled bee abundance declined across 23% of US land area. This decline was generally associated with conversion of natural habitats to row crops. We identify 139 counties where low bee abundances correspond to large areas of pollinator-dependent crops. These areas of mismatch between supply (wild bee abundance) and demand (cultivated area) for pollination comprise 39% of the pollinator-dependent crop area in the United States. Further, we find that the crops most highly dependent on pollinators tend to experience more severe mismatches between declining supply and increasing demand. These trends, should they continue, may increase costs for US farmers and may even destabilize crop production over time. National assessments such as this can help focus both scientific and political efforts to understand and sustain wild bees. As new information becomes available, repeated assessments can update findings, revise priorities, and track progress toward sustainable management of our nation's pollinators.

As abelhas sao os principais polinizadores na natureza, sendo de fundamental importância na conducao de muitas culturas agricolas ao redor do mundo, promovendo varias melhorias na cadeia produtiva da agricultura. A polinizacao realizada por abelhas contribui para a melhoria da qualidade e/ou a quantidade de frutos e sementes produzidos. Entretanto, apesar de toda importância, as abelhas encontram-se em processo de desaparecimento em varias partes do mundo, principalmente na Europa e em alguns paises da America do Norte. Pesquisas recentes estao mostrando um grande declinio das abelhas nativas e abelhas meliferas ( Apis mellifera ), principalmente como consequencia das alteracoes ambientais, que provocam severos efeitos negativos na disponibilidade de alimentos disponiveis para as abelhas. Assim essa revisao tem como objetivo, reforcar a importância das abelhas da polinizacao agricola e alertar sobre a atual situacao e o declinio populacional de diferentes grupos desses importantes polinizadores. Population decline of crop bee pollinators Bees are the main pollinators in nature, being of fundamental importance of many agricultural crops around the world, causing improvements in the productivity of these crops. The pollination by bees contributes to improving the quality and / or quantity of produced fruits and seeds. However, despite all importance, the bees are in the process of disappearing in several parts of the world, mainly in Europe and in some countries in North America. Recent surveys are showing a large decline in native bees and honeybees ( Apis mellifera ), mainly as a result of environmental changes, that cause severe negative effects on the availability of food for the bees. So, this review aims to reinforce the importance of bees in crop pollination, and warn about the current situation and the population decline of different groups of these important pollinators.

To better understand the relationship between Spondias mombin (Anacardiaceae) with its floral visitors, we investigated stigma receptivity and flowering pattern, as well as the abundance, frequency and behavior of bees visiting its flowers, aiming to discuss their potential as pollinator of this plant species. We studied S. mombin in an orchard in Northeastern Brazil. Stigma receptivity coincided with the time bees were foraging, mainly for pollen. According to the bee behavior on flowers, their visiting hour, abundance, and frequency in the studied area, we concluded that Apis mellifera (Linnaeus), Trigona spinipes (Fabricius), Xylocopa grisescens (Lepeletier) and Augochloropsis sp. are potential pollinators of S. mombin. Also, A. mellifera and T. spinipes were the most abundant species in the area and collected floral resources with greater frequency, contributing more significantly to pollination. Due to the overwhelmingly presence of these two bee species in NE Brazil, we conclude they are the main potential pollinators of S. mombin in the region. Para comprender mejor la relación entre Spondias mombin (Anacardiaceae) y sus visitantes florales, investigamos la receptividad del estigma y el patrón de floración, así como la abundancia, frecuencia y comportamiento de las abejas que visitan sus flores, con el fin de discutir su potencial como polinizadores de esta frutífera. Estudiamos esta relación en un cultivo en el noreste de Brasil. La receptividad del estigma ocorrió en el momento en que las abejas visitaban las flores para recolectar recursos, principalmente polen. De acuerdo al comportamiento de las abejas en flores, horarios de visita, abundancia y frecuencia en el área estudiada, se concluye que Apis mellifera (Linnaeus), Trigona spinipes (Fabricius), Xylocopa grisescens (Lepeletier) y Augochloropsis sp. son polinizadores potenciales de S. mombin. Además, A. mellifera y T. spinipes fueron las especies más abundantes en el área y recolectaron recursos florales con mayor frecuencia, contribuyendo más significativamente a la polinización y la fructificación inicial que otras especies de abejas. Debido a la abundante presencia de estas dos especies de abejas en el noreste de Brasil, concluimos que son los principales potenciales polinizadores de S. mombin en la región. Para compreender melhor a relação entre Spondias mombin (Anacardiaceae) e seus visitantes florais, investigamos a receptividade do estigma e o padrão de florescimento, bem como a abundância, frequência e o comportamento das abelhas que visitam suas flores, com o objetivo de discutir seu potencial como polinizadores desta espécie de planta. Estudamos essa relação em um pomar no Nordeste do Brasil. A receptividade do estigma coincidiu com o momento em que as abelhas visitavam as flores para coleta de recursos, principalmente pólen. De acordo com o comportamento das abelhas nas flores, horário de visitas, abundância e frequência na área estudada, concluímos que Apis mellifera (Linnaeus), Trigona spinipes (Fabricius), Xylocopa grisescens (Lepeletier) e Augochloropsis sp. são potenciais polinizadores de S. mombin. Além disso, A. mellifera e T. spinipes foram as espécies mais abundantes na área e coletaram recursos florais com maior frequência, contribuindo de forma mais significativa para a polinização. Devido à abundante presença dessas duas espécies de abelhas no Nordeste do Brasil, concluímos que elas são os principais potenciais polinizadores de S. mombin na região.

Globally, agriculture increasingly depends on pollinators to produce many seed and fruit crops. However, what constitutes optimal pollination service for pollinator-dependent crops remains unanswered. We developed a simulation model to identify the optimal pollination service that maximizes fruit quality in crops. The model depicts the pollination (i.e., autonomous self-fertilization, pollen deposition) and post-pollination (i.e., pollen germination, and time from germination to ovule fertilization) processes leading to fruit and seed set and allows for negative flower–pollinator interactions, specifically pistil damage. We parameterized and validated the model based on empirical observations of commercial raspberry in western Argentina. To assess the effects of pollination intensity for fruit production, we conducted simulations over a range of visit number per flower by the two primary managed pollinators worldwide, Apis mellifera and Bombus terrestris. Simulations identified that ~15–35 visits per flower by A. mellifera or ~10–20 visits by B. terrestris provide adequate pollination and maximize raspberry fruit quality (i.e., estimated as the proportion of ovules that develop into drupelets). Visits in excess of these optima reduce simulated fruit quality, and flowers receiving >670 honey bee visits or >470 bumble bee visits would produce fruits of poorer quality than those receiving no bee visits. The simulations generated consistent, unbiased predictions of fruit quality for 12 raspberry fields. This model could be adapted easily to other animal-pollinated crops and used to guide efficient pollinator management in any agro-ecosystem. Fil: Sáez, Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Morales, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Morales, Carolina Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Harder, Lawrence D.. University of Calgary. Departament of Biological Sciences; Canadá Fil: Aizen, Marcelo Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

Insect crop visitations do not necessarily translate to carriage or transfer of pollen. To evaluate the potential of the various insects visiting hybrid carrot flowers to facilitate pollen transfer, this study examines insect visitation rates to hybrid carrot seed crops in relation to weather, time of day and season, pollen carrying capacity, inter-row movement, and visitation frequency to male-fertile and male-sterile umbels. The highest pollen loads were carried by nectar scarabs, honey bees, and the hover fly Eristalis tenax (Linnaeus). Honey bees and muscoid flies were observed to forage mostly within the male fertile carrot row while nectar scarabs and E. tenax foraged across rows, carrying equal pollen loads regardless of their distance from the pollen source. All observed insect taxa were more frequently seen visiting male-fertile than male-sterile umbels. In contrast to other visiting insects, honey bees were abundant and frequent visitors and were observed carrying high pollen loads. Consequently, we suggest both optimizing honey bee management and improving the attraction of carrot lines to honey bees to improve pollination rates for hybrid carrot seed crops.

The notion that robotic crop pollination will solve the decline in pollinators has gained wide popularity recently (Fig. 1), and in March 2018 Walmart filed a patent for autonomous robot bees. However, w present six arguments showing that this is a technically and economically inviable ‘solution’ at present and poses substantial ecological and moral risks: (1) despite recent advances, robotic pollination is far from being able to replace bees to pollinate crops efficiently; (2) using robots is very unlikely to be economically viable; (3) there would be unacceptably high environmental costs; (4) wider ecosystems would be damaged; (5) it would erode the values of biodiversity; and, (6) relying on robotic pollination could actually lead to major food insecurity., SCOPUS: no.j, info:eu-repo/semantics/published

Onion (Allium cepa L.) is one of the main vegetable crops. Pollinators are required for onion seed production, being honeybees the most used. Around the world, two types of onion varieties are grown: open pollinated (OP) and hybrids. Hybrids offer numerous advantages to growers, but usually have lower seed yields than OP cultivars, which in many cases compromise the success of new hybrids. As pollination is critical for seed set, understanding the role of floral rewards and attractants to pollinator species is the key to improve crop seed yield. In this study, the correlation of nectar-analyzed compounds, floral traits, and seed yield under open field conditions in two experimental sites was determined. Nectar composition was described through the analysis of sugars, phenol, and alkaloid compounds. Length and width of the style and tepals of the flowers were measured to describe floral traits. Floral and nectar traits showed differences among the studied lines. For nectar traits, we found a significant influence of the environment where plants were cultivated. Nonetheless, flower traits were not influenced by the experimental sites.The OP and the male-sterile lines (MSLs) showed differences in nectar chemical composition and floral traits. In addition, there were differences between and within MSLs, some of which were correlated with seed yield, bringing the opportunity to select the most productive MSL, using simple determinations of morphological characters like the length of the style or tepals size. Fil: Soto Vargas, Verónica Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentina Fil: Caselles, Cristian A. Monsanto; Argentina Fil: Silva, María Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentina Fil: Galmarini, Claudio Romulo. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; Argentina

This literature review seeks to provide an outlook of the use of Western honeybee for crop pollination around the world. It was prepared by collecting information on the use of managed honey bees, Apis mellifera in crop pollination from different sources. To address pollination deficits, farmers around the world contract with beekeepers that provide colonies of Western honey, Apis mellifera , in order to perform crop pollination. Some farmers pay for the bee colonies they host in their farms; while others obtain them for free. Apis mellifera is widely used for pollination purposes for several reasons, including its polylectic nature, its wide distribution, its relatively ease and low cost management, and hive products from which the beekeeper get additional incomes. The Western honey bee is used to pollinate 66 commodities on all continents, except Antarctica. A controlled use of Western honey bee for pollination services is reported mainly in developed countries. Because of the low application of this technology in Africa, research must be conducted in order to access the need of pollination service and then the profitability of this technology in the current African entomological fauna context. Despite its benefits, the use of managed Western honey bees can affect native pollinators and contribute to the spread of diseases, parasites and weeds. Key words: Apis mellifera , bee colonies, pollination deficit, pollination services

International audience; AbstractThe magnitude and the stability of pollination services in entomophilous crops both depend not only on honeybee management but also on the diversity of wild pollinators, which enables additive contributions and replacement of species. This work evaluated the functional niche of cider apple pollinators in Spain and found a highly heterogeneous community of pollinators in taxonomic and functional terms. Through different niche dimensions, our results suggest complementarity (i.e. niche differentiation) in the contribution of the various groups to pollination, through differences in abundance, foraging behaviour, diet and daytime and canopy distribution patterns, as well as redundancy (i.e. niche similarity) in their responses to environmental conditions. Thus, quantitative and qualitative complementarity would promote an additive effect of different insects on pollination, while similarity in environmental response would provide insurance against potential honeybee loss.

International audience; As the Anthropocene advances, understanding the complex web of interactions between species has become a central theme in the maintenance of biodiversity, ecosystem functions, and agricultural systems. Plant-flower visitor networks yield insights into how natural vegetation supports crop pollination. Although crops themselves also support pollinators, the importance of spillover of flower-visiting pollinators from natural vegetation into croplands is increasingly appreciated. Natural vegetation not only provides forage and nesting sites, but can also support crop flower visitors when the crop is not flowering. We evaluated indirect effects between mango (the dominant tropical fruit crop globally) and wild plant species in neighbouring vegetation, and the factors determining these indirect effects, by constructing flower visitor networks. We constructed these networks for transects that included mango fields and neighbouring natural vegetation in northeastern South Africa. Surveys were conducted before, during and after mango flowering, to allow evaluation of the importance of pollinator support when the crop was not in flower. Network analysis showed that potential indirect effects of other plant species on mango increased with flower abundance of those species, although this increase was less marked for species growing in natural vegetation. The cumulative (total, i.e. indirect effects summed) effect of natural vegetation on mango flower visitation was greater both during mango flowering and when it was not flowering. This is likely because of the greater plant diversity in natural systems, and because the combination of these species provided flowers over a protracted period. These positive indirect effects among plants flowering over extended periods of time have to date rarely been considered in crop pollination studies. Given the rapid expansion of high-intensity, high-yield monoculture plantings, such effects warrant further investigation.

International audience; AbstractDeclines in honey bee health and increasing demand for pollination services highlight a need to optimize crop pollination by wild bees. Apple is an economically important crop in eastern North America, requires insect pollination, and is visited by a diverse bee fauna, but a direct assessment of wild bee pollination in apple orchards is lacking. We combined measurements of two facets of pollination service, per-visit efficiency (fruit and seed set) and relative abundance, to estimate orchard-level, pollinator importance of mining bees (Andrena subgenus Melandrena), bumble bees (Bombus), and honey bees (Apis mellifera L.). Average pollinator importance provided a relative measure that allowed comparison of pollination service among the three focal bees across the study region. On average, a wild bee visit resulted in higher pollen transfer to stigmas, but had the same probability of setting fruit and seed as a honey bee visit. Regionally, pollinator importance of Melandrena and Bombus were 32 and 14 % that of honey bees, respectively. Because per-visit performances were similar, such disparities in importance were based largely on differences in relative abundance. Although the summed pollinator importance of Melandrena and Bombus was less than that of the honey bee, these, and other, wild pollinators have a role to play in filling future pollination gaps, and thus, warrant further study and conservation.

Honey bees (Apis mellifera) pollinate melon (Cucumis melo) and improve production and quality of fruits. However, little is known about bee behavior and number of hives required. The aims of this study were to compare bees visiting flowers in crop areas with different number of hives (0, 1, 2, and 3), and to evaluate which is the best number. Flowers were observed (n=78) from 5 am to 6 pm, for five consecutive days, in four experimental areas (0.5ha each). Comparisons were made for male (MF) and hermaphrodite (HF) flowers, number of hives and fruit production. The HF were always more visited than MF. Most comparisons made for three hives presented significant differences, since visits increased drastically, competition among bees for floral resources became stronger and reduced the production of commercial fruit (93.4%). On the other hand, the highest percentage of commercial fruit was obtained (99%) with two hives, setting the ideal number of hives as four hives ha-1. As abelhas melíferas (Apis mellifera) polinizam o melão (Cucumis melo) e melhoram a produção e qualidade dos frutos. Entretanto, pouco é conhecido sobre seu comportamento e o número de colmeias necessário. Os objetivos deste trabalho foram comparar a visitação das abelhas nas flores em áreas de cultivo com diferente número de colmeias (0,1, 2 e 3) e avaliar a produção de frutos em cada situação. Nas quatro áreas experimentais (0,5 ha cada), foram observadas flores (n=78), de 5 às 18h, por cinco dias consecutivos. Foram realizadas comparações para as flores masculinas (FM) e hermafroditas (FH), número de colmeias e produção de frutos. Os resultados mostraram que sempre as FH foram mais visitadas que as FM. A maioria das comparações feitas para três colmeias apresentaram diferenças significativas, já que as visitas aumentaram drasticamente. Provavelmente, a competição entre as abelhas pelos recursos florais foi maior e reduziu a produção de frutos comerciais (93,4%). Por outro lado, com duas colmeias, obteve-se a maior porcentagem de frutos comerciais (99%), indicando que o número ideal é de quatro colmeias ha-1.