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Kaspari M, Welti EAR. Nutrient dilution and the future of herbivore populations. Trends Ecol Evol 2024:S0169-5347(24)00112-5. [PMID: 38876933 DOI: 10.1016/j.tree.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 04/29/2024] [Accepted: 05/02/2024] [Indexed: 06/16/2024]
Abstract
Nutrient dilution (ND) - the decrease in the concentration of nutritional elements in plant tissue - arises from an increase in the mass of carbohydrates and/or a decrease in the 20+ essential elements. Increasing CO2 levels and its promotion of biomass are linked to nutrient dilution. We build a case for nutrient dilution as a key driver in global declines in herbivore abundance. Herbivores must build element-rich animal tissue from nutrient-poor plant tissue, and their abundance commonly increases with fertilization of both macro- and micronutrients. We predict the global impacts of nutrient dilution will be magnified in some of Earth's most biodiverse, highly productive, and/or nutrient-poor ecosystems and should favor specific traits of herbivores, including sap-feeding and ruminant microbiomes.
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Affiliation(s)
- Michael Kaspari
- School of Biological Sciences, University of Oklahoma, Norman, OK 73019, USA; Conservation Ecology Center, Smithsonian's National Zoo and Conservation Biology Institute, Front Royal, VA 22630, USA.
| | - Ellen A R Welti
- Conservation Ecology Center, Smithsonian's National Zoo and Conservation Biology Institute, Front Royal, VA 22630, USA
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2
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Vaudo AD, Dyer LA, Leonard AS. Pollen nutrition structures bee and plant community interactions. Proc Natl Acad Sci U S A 2024; 121:e2317228120. [PMID: 38190523 PMCID: PMC10801918 DOI: 10.1073/pnas.2317228120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 11/19/2023] [Indexed: 01/10/2024] Open
Abstract
As bees' main source of protein and lipids, pollen is critical for their development, reproduction, and health. Plant species vary considerably in the macronutrient content of their pollen, and research in bee model systems has established that this variation both modulates performance and guides floral choice. Yet, how variation in pollen chemistry shapes interactions between plants and bees in natural communities is an open question, essential for both understanding the nutritional dynamics of plant-pollinator mutualisms and informing their conservation. To fill this gap, we asked how pollen nutrition (relative protein and lipid content) sampled from 109 co-flowering plant species structured visitation patterns observed among 75 subgenera of pollen-collecting bees in the Great Basin/Eastern Sierra region (USA). We found that the degree of similarity in co-flowering plant species' pollen nutrition predicted similarity among their visitor communities, even after accounting for floral morphology and phylogeny. Consideration of pollen nutrition also shed light on the structure of this interaction network: Bee subgenera and plant genera were arranged into distinct, interconnected groups, delineated by differences in pollen macronutrient values, revealing potential nutritional niches. Importantly, variation in pollen nutrition alone (high in protein, high in lipid, or balanced) did not predict the diversity of bee visitors, indicating that plant species offering complementary pollen nutrition may be equally valuable in supporting bee diversity. Nutritional diversity should thus be a key consideration when selecting plants for habitat restoration, and a nutritionally explicit perspective is needed when considering reward systems involved in the community ecology of pollination.
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Affiliation(s)
- Anthony D. Vaudo
- Department of Biology, University of Nevada, Reno, NV89557
- Rocky Mountain Research Station, United States Department of Agriculture Forest Service, Moscow, ID83843
| | - Lee A. Dyer
- Department of Biology, University of Nevada, Reno, NV89557
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3
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Rodríguez-Pólit C, Gonzalez-Pastor R, Heredia-Moya J, Carrera-Pacheco SE, Castillo-Solis F, Vallejo-Imbaquingo R, Barba-Ostria C, Guamán LP. Chemical Properties and Biological Activity of Bee Pollen. Molecules 2023; 28:7768. [PMID: 38067498 PMCID: PMC10708394 DOI: 10.3390/molecules28237768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/18/2023] [Accepted: 11/21/2023] [Indexed: 12/18/2023] Open
Abstract
Pollen, a remarkably versatile natural compound collected by bees for its abundant source of proteins and nutrients, represents a rich reservoir of diverse bioactive compounds with noteworthy chemical and therapeutic potential. Its extensive biological effects have been known and exploited since ancient times. Today, there is an increased interest in finding natural compounds against oxidative stress, a factor that contributes to various diseases. Recent research has unraveled a multitude of biological activities associated with bee pollen, ranging from antioxidant, anti-inflammatory, antimicrobial, and antifungal properties to potential antiviral and anticancer applications. Comprehending the extensive repertoire of biological properties across various pollen sources remains challenging. By investigating a spectrum of pollen types and their chemical composition, this review produces an updated analysis of the bioactive constituents and the therapeutic prospects they offer. This review emphasizes the necessity for further exploration and standardization of diverse pollen sources and bioactive compounds that could contribute to the development of innovative therapies.
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Affiliation(s)
- Cristina Rodríguez-Pólit
- Centro de Investigación Biomédica (CENBIO), Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito 170527, Ecuador; (R.G.-P.); (J.H.-M.); (S.E.C.-P.); (F.C.-S.)
- Centro de Referencia Nacional de Genómica, Secuenciación y Bioinformática, Instituto Nacional de Investigación en Salud Pública “Leopoldo Izquieta Pérez”, Quito 170403, Ecuador;
- Escuela de Salud Pública, Universidad San Francisco de Quito USFQ, Quito 170527, Ecuador
| | - Rebeca Gonzalez-Pastor
- Centro de Investigación Biomédica (CENBIO), Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito 170527, Ecuador; (R.G.-P.); (J.H.-M.); (S.E.C.-P.); (F.C.-S.)
| | - Jorge Heredia-Moya
- Centro de Investigación Biomédica (CENBIO), Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito 170527, Ecuador; (R.G.-P.); (J.H.-M.); (S.E.C.-P.); (F.C.-S.)
| | - Saskya E. Carrera-Pacheco
- Centro de Investigación Biomédica (CENBIO), Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito 170527, Ecuador; (R.G.-P.); (J.H.-M.); (S.E.C.-P.); (F.C.-S.)
| | - Fabián Castillo-Solis
- Centro de Investigación Biomédica (CENBIO), Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito 170527, Ecuador; (R.G.-P.); (J.H.-M.); (S.E.C.-P.); (F.C.-S.)
| | - Roberto Vallejo-Imbaquingo
- Departamento de Estudios Organizacionales y Desarrollo Humano DESODEH, Facultad de Ciencias Administrativas, Escuela Politécnica Nacional, Quito 170525, Ecuador;
| | - Carlos Barba-Ostria
- Escuela de Medicina, Colegio de Ciencias de la Salud Quito, Universidad San Francisco de Quito USFQ, Quito 170901, Ecuador;
- Instituto de Microbiología, Universidad San Francisco de Quito USFQ, Quito 170901, Ecuador
| | - Linda P. Guamán
- Centro de Investigación Biomédica (CENBIO), Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito 170527, Ecuador; (R.G.-P.); (J.H.-M.); (S.E.C.-P.); (F.C.-S.)
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4
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Crone MK, Boyle NK, Bresnahan ST, Biddinger DJ, Richardson RT, Grozinger CM. More than mesolectic: Characterizing the nutritional niche of Osmia cornifrons. Ecol Evol 2023; 13:e10640. [PMID: 37869440 PMCID: PMC10589078 DOI: 10.1002/ece3.10640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 09/18/2023] [Accepted: 10/09/2023] [Indexed: 10/24/2023] Open
Abstract
Characterizing the nutritional needs of wild bee species is an essential step to better understanding bee biology and providing suitable supplemental forage for at-risk species. Here, we aim to characterize the nutritional needs of a model solitary bee species, Osmia cornifrons (Radoszkowski), by using dietary protein-to-lipid ratio (P:L ratio) as a proxy for nutritional niche and niche breadth. We first identified the mean target P:L ratio (~3.02:1) and P:L collection range (0.75-6.26:1) from pollen provisions collected across a variety of sites and time points. We then investigated the P:L tolerance range of larvae by rearing bees in vitro on a variety of diets. Multifloral and single-source pollen diets with P:L ratios within the range of surveyed provisions did not always support larval development, indicating that other dietary components such as plant secondary compounds and micronutrients must also be considered in bee nutritional experiments. Finally, we used pollen metabarcoding to identify pollen from whole larval provisions to understand how much pollen bees used from plants outside of their host plant families to meet their nutritional needs, as well as pollen from individual forager bouts, to observe if bees maintained strict floral constancy or visited multiple plant genera per foraging bout. Whole larval provision surveys revealed a surprising range of host plant pollen use, ranging from ~5% to 70% of host plant pollen per provision. Samples from individual foraging trips contained pollen from multiple genera, suggesting that bees are using some form of foraging decision making. Overall, these results suggest that O. cornifrons have a wide nutritional niche breadth, but while pollen P:L ratio tolerance is broad, a tolerable P:L ratio alone is not enough to create a quality diet for O. cornifrons, and the plant species that make up these diets must also be carefully considered.
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Affiliation(s)
- Makaylee K. Crone
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPennsylvaniaUSA
- Intercollege Graduate Program in Ecology, Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Natalie K. Boyle
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Sean T. Bresnahan
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPennsylvaniaUSA
- Intercollege Graduate Degree Program in Molecular, Cellular, and Integrative Biosciences, Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - David J. Biddinger
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPennsylvaniaUSA
- Penn State Fruit Research and Extension CenterBiglervillePennsylvaniaUSA
| | | | - Christina M. Grozinger
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPennsylvaniaUSA
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Bernklau E, Arathi HS. Seasonal patterns of beneficial phytochemical availability in honey and stored pollen from honey bee colonies in large apiaries. JOURNAL OF ECONOMIC ENTOMOLOGY 2023; 116:1069-1077. [PMID: 37247384 DOI: 10.1093/jee/toad096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 04/24/2023] [Accepted: 05/10/2023] [Indexed: 05/31/2023]
Abstract
Honey bees (Apis mellifera L.; Hymenoptera, Apidae) are the most efficient pollinators in agroecosystems, responsible for the successful production of fruits, nuts, and vegetables, but they continue to face debilitating challenges. One of the major factors leading to these challenges could be linked to poor nutrition that results in weakening the colony, increasing susceptibility to pests and pathogens, and reducing the ability of bees to adapt to other abiotic stresses. Extensively used for commercial pollination, honey bee colonies regularly face exposure to limited diversity in their pollen diet as they are placed in flowering monocrops. Lack of access to diverse plant species compromises the availability of plant secondary compounds (phytochemicals), which, in small amounts, provide significant benefits to honey bee health. We analyzed the beneficial phytochemical content of honey and stored pollen (bee bread) samples from colonies in large apiaries through the active bee season. Samples were evaluated for 4 beneficial phytochemicals (caffeine, kaempferol, gallic acid, and p-coumaric acid), which have previously been shown to improve honey bee health. Our results, as relevant to the apiary locations in the study, indicated that p-coumaric acid is uniformly available throughout the season. Caffeine is completely absent, and gallic acid and kaempferol are not regularly available. Our results suggest the need to explore the potential to deliver beneficial phytochemicals as nutritional supplements to improve bee health. It may be vital for the pollination industry to consider such targeted dietary supplementation as beekeepers strive to meet the increasing demand for crop pollination services.
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Affiliation(s)
- Elisa Bernklau
- Department of Agricultural Biology, Colorado State University, Fort Collins, CO 80525, USA
| | - H S Arathi
- Invasive Species and Pollinator Health Research Unit, USDA-ARS, Davis, CA 95616, USA
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Filipiak ZM, Ollerton J, Filipiak M. Uncovering the significance of the ratio of food K:Na in bee ecology and evolution. Ecology 2023; 104:e4110. [PMID: 37232411 DOI: 10.1002/ecy.4110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 05/04/2023] [Accepted: 05/18/2023] [Indexed: 05/27/2023]
Abstract
Bees provide important ecological services, and many species are threatened globally, yet our knowledge of wild bee ecology and evolution is limited. While evolving from carnivorous ancestors, bees had to develop strategies for coping with limitations imposed on them by a plant-based diet, with nectar providing energy and essential amino acids and pollen as an extraordinary, protein- and lipid-rich food nutritionally similar to animal tissues. Both nectar and pollen display one characteristic common to plants, a high ratio of potassium to sodium (K:Na), potentially leading to bee underdevelopment, health problems, and death. We discuss why and how the ratio of K:Na contributes to bee ecology and evolution and how considering this factor in future studies will provide new knowledge, more accurately depicting the relationship of bees with their environments. Such knowledge is essential for understanding how plants and bees function and interact and is needed to effectively protect wild bees.
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Affiliation(s)
- Zuzanna M Filipiak
- Institute of Nature Conservation, Polish Academy of Sciences, Kraków, Poland
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, Poland
| | - Jeff Ollerton
- Faculty or Arts, Science and Technology, University of Northampton, Northampton, UK
- Kunming Institute of Botany, Kunming, China
| | - Michał Filipiak
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, Poland
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Russo L, Ruedenauer F, Gronert A, Van de Vreken I, Vanderplanck M, Michez D, Klein A, Leonhardt S, Stout JC. Fertilizer and herbicide alter nectar and pollen quality with consequences for pollinator floral choices. PeerJ 2023; 11:e15452. [PMID: 37334137 PMCID: PMC10269573 DOI: 10.7717/peerj.15452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 05/03/2023] [Indexed: 06/20/2023] Open
Abstract
Background Pollinating insects provide economically and ecologically valuable services, but are threatened by a variety of anthropogenic changes. The availability and quality of floral resources may be affected by anthropogenic land use. For example, flower-visiting insects in agroecosystems rely on weeds on field edges for foraging resources, but these weeds are often exposed to agrochemicals that may compromise the quality of their floral resources. Methods We conducted complementary field and greenhouse experiments to evaluate the: (1) effect of low concentrations of agrochemical exposure on nectar and pollen quality and (2) relationship between floral resource quality and insect visitation. We applied the same agrochemcial treatments (low concentrations of fertilizer, low concentrations of herbicide, a combination of both, and a control of just water) to seven plant species in the field and greenhouse. We collected data on floral visitation by insects in the field experiment for two field seasons and collected pollen and nectar from focal plants in the greenhouse to avoid interfering with insect visitation in the field. Results We found pollen amino acid concentrations were lower in plants exposed to low concentrations of herbicide, and pollen fatty acid concentrations were lower in plants exposed to low concentrations of fertilizer, while nectar amino acids were higher in plants exposed to low concentrations of either fertilizer or herbicide. Exposure to low fertilizer concentrations also increased the quantity of pollen and nectar produced per flower. The responses of plants exposed to the experimental treatments in the greenhouse helped explain insect visitation in the field study. The insect visitation rate correlated with nectar amino acids, pollen amino acids, and pollen fatty acids. An interaction between pollen protein and floral display suggested pollen amino acid concentrations drove insect preference among plant species when floral display sizes were large. We show that floral resource quality is sensitive to agrochemical exposure and that flower-visiting insects are sensitive to variation in floral resource quality.
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Affiliation(s)
- Laura Russo
- University of Tennessee, Knoxville, United States of America
- Trinity College Dublin, Dublin, Ireland
| | | | - Angela Gronert
- Chair of Nature Conservation and Landscape Ecology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | | | | | | | - Alexandra Klein
- Chair of Nature Conservation and Landscape Ecology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
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Kacemi R, Campos MG. Translational Research on Bee Pollen as a Source of Nutrients: A Scoping Review from Bench to Real World. Nutrients 2023; 15:nu15102413. [PMID: 37242296 DOI: 10.3390/nu15102413] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/11/2023] [Accepted: 05/15/2023] [Indexed: 05/28/2023] Open
Abstract
The emphasis on healthy nutrition is gaining a forefront place in current biomedical sciences. Nutritional deficiencies and imbalances have been widely demonstrated to be involved in the genesis and development of many world-scale public health burdens, such as metabolic and cardiovascular diseases. In recent years, bee pollen is emerging as a scientifically validated candidate, which can help diminish conditions through nutritional interventions. This matrix is being extensively studied, and has proven to be a very rich and well-balanced nutrient pool. In this work, we reviewed the available evidence on the interest in bee pollen as a nutrient source. We mainly focused on bee pollen richness in nutrients and its possible roles in the main pathophysiological processes that are directly linked to nutritional imbalances. This scoping review analyzed scientific works published in the last four years, focusing on the clearest inferences and perspectives to translate cumulated experimental and preclinical evidence into clinically relevant insights. The promising uses of bee pollen for malnutrition, digestive health, metabolic disorders, and other bioactivities which could be helpful to readjust homeostasis (as it is also true in the case of anti-inflammatory or anti-oxidant needs), as well as the benefits on cardiovascular diseases, were identified. The current knowledge gaps were identified, along with the practical challenges that hinder the establishment and fructification of these uses. A complete data collection made with a major range of botanical species allows more robust clinical information.
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Affiliation(s)
- Rachid Kacemi
- Observatory of Drug-Herb Interactions, Laboratory of Pharmacognosy, Faculty of Pharmacy, University of Coimbra, Heath Sciences Campus, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - Maria G Campos
- Observatory of Drug-Herb Interactions, Laboratory of Pharmacognosy, Faculty of Pharmacy, University of Coimbra, Heath Sciences Campus, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
- Coimbra Chemistry Centre (CQC, FCT Unit 313), Faculty of Science and Technology, University of Coimbra, Rua Larga, 3004-516 Coimbra, Portugal
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Powell JE, Lau P, Rangel J, Arnott R, De Jong T, Moran NA. The microbiome and gene expression of honey bee workers are affected by a diet containing pollen substitutes. PLoS One 2023; 18:e0286070. [PMID: 37205696 PMCID: PMC10198554 DOI: 10.1371/journal.pone.0286070] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 05/08/2023] [Indexed: 05/21/2023] Open
Abstract
Pollen is the primary source of dietary protein for honey bees. It also includes complex polysaccharides in its outer coat, which are largely indigestible by bees but can be metabolized by bacterial species within the gut microbiota. During periods of reduced availability of floral pollen, supplemental protein sources are frequently provided to managed honey bee colonies. The crude proteins in these supplemental feeds are typically byproducts from food manufacturing processes and are rarely derived from pollen. Our experiments on the impact of different diets showed that a simplified pollen-free diet formulated to resemble the macronutrient profile of a monofloral pollen source resulted in larger microbial communities with reduced diversity, reduced evenness, and reduced levels of potentially beneficial hive-associated bacteria. Furthermore, the pollen-free diet sharply reduced the expression of genes central to honey bee development. In subsequent experiments, we showed that these shifts in gene expression may be linked to colonization by the gut microbiome. Lastly, we demonstrated that for bees inoculated with a defined gut microbiota, those raised on an artificial diet were less able to suppress infection from a bacterial pathogen than those that were fed natural pollen. Our findings demonstrate that a pollen-free diet significantly impacts the gut microbiota and gene expression of honey bees, indicating the importance of natural pollen as a primary protein source.
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Affiliation(s)
- J. Elijah Powell
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, United States of America
| | - Pierre Lau
- Department of Entomology, Texas A&M University, College Station, TX, United States of America
- USDA-ARS, Pollinator Health in Southern Crop Ecosystem Research Unit, Stoneville, MS, United States of America
| | - Juliana Rangel
- Department of Entomology, Texas A&M University, College Station, TX, United States of America
| | - Ryan Arnott
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, United States of America
| | - Tyler De Jong
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, United States of America
| | - Nancy A. Moran
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, United States of America
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Filipiak M, Shields MW, Cairns SM, Grainger MNC, Wratten SD. The conserved and high K-to-Na ratio in sunflower pollen: Possible implications for bee health and plant-bee interactions. FRONTIERS IN PLANT SCIENCE 2022; 13:1042348. [PMID: 36388528 PMCID: PMC9664163 DOI: 10.3389/fpls.2022.1042348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 10/13/2022] [Indexed: 06/16/2023]
Abstract
Sodium (Na) concentrations are low in plant tissues, and its metabolic function in plants is minor; however, Na is a key nutrient for plant consumers. Previous studies have thus far focused on Na concentration. Nevertheless, a balanced potassium (K) to Na ratio (K:Na) is more important than Na concentration alone since food with high K:Na has detrimental effects on consumers irrespective of Na concentration. Therefore, plants may actively regulate K:Na in their tissues and products, shaping plant-insect interactions. Studies considering nutritional aspects of plant-insect interactions have focused on nonreproductive tissues and nectar. In this study, we consider pollen as serving a primary reproductive function for plants as well as a food of pollinivores. Plants might regulate K:Na in pollen to affect their interactions with pollinivorous pollinators. To investigate whether such a mechanism exists, we manipulated Na concentrations in soil and measured the proportion of K, Na, and 13 other nutrient elements in the pollen of two sunflower (Helianthus annuus) cultivars. This approach allowed us to account for the overall nutritional quality of pollen by investigating the proportions of many elements that could correlate with the concentrations of K and Na. Of the elements studied, only the concentrations of Na and K were highly correlated. Pollen K:Na was high in both cultivars irrespective of Na fertilization, and it remained high regardless of pollen Na concentration. Interestingly, pollen K:Na did not decrease as pollen increased the Na concentration. We hypothesize that high K:Na in pollen might benefit plant fertilization and embryonic development; therefore, a tradeoff might occur between producing low K:Na pollen as a reward for pollinators and high K:Na pollen to optimize the plant fertilization process. This is the first study to provide data on pollen K:Na regulation by plants. Our findings broaden the understanding of plant-bee interactions and provide a foundation for a better understanding of the role of the soil-plant-pollen-pollinator pathway in nutrient cycling in ecosystems. Specifically, unexplored costs and tradeoffs related to balancing the K:Na by plants and pollinivores might play a role in past and current shaping of pollination ecology.
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Affiliation(s)
- Michał Filipiak
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, Poland
| | - Morgan W. Shields
- Bio-Protection Research Centre, Lincoln University, Lincoln, New Zealand
| | - Sarah M. Cairns
- Bio-Protection Research Centre, Lincoln University, Lincoln, New Zealand
| | | | - Stephen D. Wratten
- Bio-Protection Research Centre, Lincoln University, Lincoln, New Zealand
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11
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Gekière A, Michez D, Vanderplanck M. Bumble Bee Breeding on Artificial Pollen Substitutes. JOURNAL OF ECONOMIC ENTOMOLOGY 2022; 115:1423-1431. [PMID: 36000563 DOI: 10.1093/jee/toac126] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Indexed: 06/15/2023]
Abstract
Bumble bees are important pollinators for many temperate crops. Because of the growing demand for food from entomophilous crops, bumble bee colonies are commercially reared and placed in fields or greenhouses to guarantee sufficient pollination services. Besides, commercial colonies are increasingly used in laboratories for various bioassays under controlled conditions. For both usages, bumble bee colonies are commonly provided with sugar solution and honey bee-collected pollen pellets. However, the latter display several disadvantages since they may contain pollutants, pathogens, or toxic phytochemicals. Consequently, companies have developed pollen-free artificial diets to sustain colonies. Such diets are designed to boost worker health in the field, in complement of floral pollen collected by workers outside the colonies, but their suitability in 'closed' systems without access to floral pollen, such as in laboratory bioassays, is arguable. Here, we used microcolonies of the commercially important bumble bee Bombus terrestris L. (Hymenoptera: Apidae) to assess the suitability of five artificial pollen substitutes and three mixed diets. We also assessed the evaporation rate of the different diets as it could impact their suitability. At the end of the bioassays, microcolonies fed the artificial diets showed a reduced offspring development when compared to microcolonies fed natural pollen, which was partly offset by mixing these diets with natural pollen. By contrast, the artificial diets did not have deleterious effects on worker's health. We discuss the potential nutritional and physical causes of artificial diets unsuitability for offspring development and encourage further research to accordingly establish appropriate pollen-free diets for bumble bee breeding.
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Affiliation(s)
- Antoine Gekière
- Laboratory de Zoology, Research institute for Biosciences, University of Mons, Mons, Belgium
| | - Denis Michez
- Laboratory de Zoology, Research institute for Biosciences, University of Mons, Mons, Belgium
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12
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Stevenson PC, Koch H, Nicolson SW, Brown MJF. Natural processes influencing pollinator health. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210154. [PMID: 35491596 PMCID: PMC9062705 DOI: 10.1098/rstb.2021.0154] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Evidence from the last few decades indicates that pollinator abundance and diversity are at risk, with many species in decline. Anthropogenic impacts have been the focus of much recent work on the causes of these declines. However, natural processes, from plant chemistry, nutrition and microbial associations to landscape and habitat change, can also profoundly influence pollinator health. Here, we argue that these natural processes require greater attention and may even provide solutions to the deteriorating outlook for pollinators. Existing studies also focus on the decline of individuals and colonies and only occasionally at population levels. In the light of this we redefine pollinator health and argue that a top-down approach is required focusing at the ecological level of communities. We use examples from the primary research, opinion and review articles published in this special issue to illustrate how natural processes influence pollinator health, from community to individuals, and highlight where some of these processes could mitigate the challenges of anthropogenic and natural drivers of change. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.
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Affiliation(s)
- Philip C Stevenson
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey TW9 3AE, UK.,Natural Resources Institute, University of Greenwich, Kent ME4 4TB, UK
| | - Hauke Koch
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey TW9 3AE, UK
| | - Susan W Nicolson
- Department of Zoology & Entomology, University of Pretoria, Pretoria 0002, South Africa
| | - Mark J F Brown
- Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
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