1
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Thiel L, Mergenthaler M, Wutke M, Haberlah-Korr V. Use of insect pest thresholds in oilseed rape and cereals: is it worth it? Pest Manag Sci 2024; 80:2353-2361. [PMID: 37402269 DOI: 10.1002/ps.7647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 05/08/2023] [Accepted: 07/05/2023] [Indexed: 07/06/2023]
Abstract
BACKGROUND Integrated pest management (IPM) uses thresholds to minimize pesticide use, and field monitoring of damaging organisms is an important component to evaluate whether or not thresholds have been breached. However, monitoring requires time and knowledge which impacts costs and benefits. In this study, we evaluated the effects of using insect pest thresholds on time effort, frequency of insecticide treatment and economics in comparison with common farm practices (business as usual) in winter wheat (WW), winter barley (WB) and winter oilseed rape (OSR). This study was done over 2 years (2018 to 2020) on 24 conventionally managed farms in North Rhine-Westphalia (Germany). RESULTS Farmers spent significantly more time (42 min ha-1/season) monitoring insect pests in OSR than in WW (16 min ha-1/season) and WB (19 min ha-1/season). The use of insecticides in OSR was significantly reduced by 42% in comparison to business as usual. In cereal crops, the use of insecticide treatment was reduced by 50% but this was not significantly different to business as usual. Yields were not significantly reduced when crops were managed in accordance with IPM, and negative differences were small and not significant. However, economically, the costs of monitoring can only be recovered when labor costs and commodity prices are low and insecticide cost is high. CONCLUSION Insect pest thresholds can help link the policy and environmental goals of insecticide reduction and the agronomic goal of production security. In the future, the time and cost required for monitoring should be reduced through intelligent solutions and tools, increasing the economic viability of monitoring and IPM. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Lukas Thiel
- Faculty of Agronomy, South Westphalia University of Applied Sciences, Soest, Germany
| | - Marcus Mergenthaler
- Faculty of Agronomy, South Westphalia University of Applied Sciences, Soest, Germany
| | - Martin Wutke
- Faculty of Agronomy, South Westphalia University of Applied Sciences, Soest, Germany
| | - Verena Haberlah-Korr
- Faculty of Agronomy, South Westphalia University of Applied Sciences, Soest, Germany
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2
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Louati K, Maalej A, Kolsi F, Kallel R, Gdoura Y, Borni M, Hakim LS, Zribi R, Choura S, Sayadi S, Chamkha M, Mnif B, Khemakhem Z, Boudawara TS, Boudawara MZ, Safta F. Shotgun Proteomic-Based Approach with a Q-Exactive Hybrid Quadrupole-Orbitrap High-Resolution Mass Spectrometer for Protein Adductomics on a 3D Human Brain Tumor Neurospheroid Culture Model: The Identification of Adduct Formation in Calmodulin-Dependent Protein Kinase-2 and Annexin-A1 Induced by Pesticide Mixture. J Proteome Res 2023; 22:3811-3832. [PMID: 37906427 PMCID: PMC10696604 DOI: 10.1021/acs.jproteome.3c00484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/27/2023] [Accepted: 10/16/2023] [Indexed: 11/02/2023]
Abstract
Pesticides are increasingly used in combinations in crop protection, resulting in enhanced toxicities for various organisms. Although protein adductomics is challenging, it remains a powerful bioanalytical tool to check environmental exposure and characterize xenobiotic adducts as putative toxicity biomarkers with high accuracy, facilitated by recent advances in proteomic methodologies and a mass spectrometry high-throughput technique. The present study aims to predict the potential neurotoxicity effect of imidacloprid and λ-cyhalothrin insecticides on human neural cells. Our protocol consisted first of 3D in vitro developing neurospheroids derived from human brain tumors and then treatment by pesticide mixture. Furthermore, we adopted a bottom-up proteomic-based approach using nanoflow ultraperformance liquid chromatography coupled with a high-resolution mass spectrometer for protein-adduct analysis with prediction of altered sites. Two proteins were selected, namely, calcium-calmodulin-dependent protein kinase-II (CaMK2) and annexin-A1 (ANXA1), as key targets endowed with primordial roles. De novo sequencing revealed several adduct formations in the active site of 82-ANXA1 and 228-CaMK2 as a result of neurotoxicity, predicted by the added mass shifts for the structure of electrophilic precursors. To the best of our knowledge, our study is the first to adopt a proteomic-based approach to investigate in depth pesticide molecular interactions and their potential to adduct proteins which play a crucial role in the neurotoxicity mechanism.
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Affiliation(s)
- Kaouthar Louati
- Faculty
of Pharmacy, Laboratory of Pharmacology, Analytics & Galenic Drug
Development-LR12ES09, University of Monastir, Road Avicenne, Monastir 5000, Tunisia
| | - Amina Maalej
- Laboratory
of Environmental Bioprocesses, Centre of
Biotechnology of Sfax, Road of Sidi-Mansour, P.O. Box 1177, Sfax 3018, Tunisia
| | - Fatma Kolsi
- Department
of Neurosurgery, Habib Bourguiba University
Hospital, Road El Ain
km 1.5, Avenue of Ferdaous, Sfax 3089, Tunisia
- Faculty
of Medicine, Avenue of Majida Boulila, University
of sfax, Sfax 3029, Tunisia
| | - Rim Kallel
- Laboratory
of Pathological Anatomy and Cytology, Habib
Bourguiba University Hospital, Road El Ain km 1.5, Avenue of Ferdaous, Sfax 3089, Tunisia
- Faculty
of Medicine, Avenue of Majida Boulila, University
of sfax, Sfax 3029, Tunisia
| | - Yassine Gdoura
- Department
of Neurosurgery, Habib Bourguiba University
Hospital, Road El Ain
km 1.5, Avenue of Ferdaous, Sfax 3089, Tunisia
- Faculty
of Medicine, Avenue of Majida Boulila, University
of sfax, Sfax 3029, Tunisia
| | - Mahdi Borni
- Department
of Neurosurgery, Habib Bourguiba University
Hospital, Road El Ain
km 1.5, Avenue of Ferdaous, Sfax 3089, Tunisia
- Faculty
of Medicine, Avenue of Majida Boulila, University
of sfax, Sfax 3029, Tunisia
| | - Leila Sellami Hakim
- Laboratory
of Pathological Anatomy and Cytology, Habib
Bourguiba University Hospital, Road El Ain km 1.5, Avenue of Ferdaous, Sfax 3089, Tunisia
| | - Rania Zribi
- Higher
Institute of Applied Studies to Humanities of Tunis (ISEAHT), University of Tunis, 11 Road of Jebel Lakdhar, Tunis 1005, Tunisia
| | - Sirine Choura
- Laboratory
of Environmental Bioprocesses, Centre of
Biotechnology of Sfax, Road of Sidi-Mansour, P.O. Box 1177, Sfax 3018, Tunisia
| | - Sami Sayadi
- Biotechnology
Program, Center for Sustainable Development, College of Arts and Sciences, Qatar University, Doha 2713, Qatar
| | - Mohamed Chamkha
- Laboratory
of Environmental Bioprocesses, Centre of
Biotechnology of Sfax, Road of Sidi-Mansour, P.O. Box 1177, Sfax 3018, Tunisia
| | - Basma Mnif
- Department
of Bacteriology, Habib Bourguiba University
Hospital, Road El Ain
km 1.5, Avenue of Ferdaous, Sfax 3089, Tunisia
- Faculty
of Medicine, Avenue of Majida Boulila, University
of sfax, Sfax 3029, Tunisia
| | - Zouheir Khemakhem
- Legal Medicine
Department, Habib Bourguiba University Hospital, Road El Ain km 1.5, Avenue of Ferdaous, Sfax 3089, Tunisia
- Faculty
of Medicine, Avenue of Majida Boulila, University
of sfax, Sfax 3029, Tunisia
| | - Tahya Sellami Boudawara
- Laboratory
of Pathological Anatomy and Cytology, Habib
Bourguiba University Hospital, Road El Ain km 1.5, Avenue of Ferdaous, Sfax 3089, Tunisia
- Faculty
of Medicine, Avenue of Majida Boulila, University
of sfax, Sfax 3029, Tunisia
| | - Mohamed Zaher Boudawara
- Department
of Neurosurgery, Habib Bourguiba University
Hospital, Road El Ain
km 1.5, Avenue of Ferdaous, Sfax 3089, Tunisia
- Faculty
of Medicine, Avenue of Majida Boulila, University
of sfax, Sfax 3029, Tunisia
| | - Fathi Safta
- Faculty
of Pharmacy, Laboratory of Pharmacology, Analytics & Galenic Drug
Development-LR12ES09, University of Monastir, Road Avicenne, Monastir 5000, Tunisia
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3
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Murrell EG, Zio KR, Chérémond NE, Van Tassel DL. Assessing effective mechanical and chemical strategies for managing Eucosma giganteana (Lepidoptera: Tortricidae) in the perennial oilseed crop, Silphium integrifolium (Asteraceae: Heliantheae). J Insect Sci 2023; 23:4. [PMID: 37987629 PMCID: PMC10661661 DOI: 10.1093/jisesa/iead102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 10/24/2023] [Accepted: 11/02/2023] [Indexed: 11/22/2023]
Abstract
Eucosma giganteana (Riley) is a native specialist pest of silflower, Silphium integrifolium Michx., which is currently being domesticated as a perennial oilseeds crop. The larvae of this moth attack silflower capitula and root crowns, causing both seed damage and long-term degradation of plants. To determine methods to manage E. giganteana in silflower crop fields, we conducted a laboratory bioassay and 3 field experiments to assess the effects of a suite of organic, conventional, and mechanical treatments on E. giganteana mortality and colonization of flower heads. Pyrethroids (permethrin, cyfluthrin), chlorantraniliprole, and methoxyfenozide each had significant insecticidal effects on E. giganteana in at least 2 of the experiments conducted. Nematodes marginally increased larva mortality in the laboratory bioassay and could be further investigated as a soil-applied biological control. In 2 separate field experiments, trimming the top 15% of silflower plants to delay flowering did not alone reduce E. giganteana colonization of flower heads throughout the growing season. However, when trimming was paired with a single chlorantraniliprole application, colonization of capitula was reduced by 83% over untreated control plants. Collectively, these experiments provide evidence for several treatments that could be further tested and incorporated into an integrated pest management strategy for E. giganteana.
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Affiliation(s)
| | - Konilo R Zio
- The Land Institute, Salina, KS, USA
- Groupe ESA, Institute of Higher Education and Research in Life Sciences, Angers, France
- Wooclap, Etterbeek, Belgium
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4
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Fattorini R, Egan PA, Rosindell J, Farrell IW, Stevenson PC. Grayanotoxin I variation across tissues and species of Rhododendron suggest pollinator-herbivore defence trade-offs. Phytochemistry 2023; 212:113707. [PMID: 37149121 DOI: 10.1016/j.phytochem.2023.113707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/25/2023] [Accepted: 05/03/2023] [Indexed: 05/08/2023]
Abstract
Grayanotoxin I (GTX I) is a major toxin in leaves of Rhododendron species, where it provides a defence against insect and vertebrate herbivores. Surprisingly, it is also present in R. ponticum nectar, and this can hold important implications for plant-pollinator mutualisms. However, knowledge of GTX I distributions across the genus Rhododendron and in different plant materials is currently limited, despite the important ecological function of this toxin. Here we characterise GTX I expression in the leaves, petals, and nectar of seven Rhododendron species. Our results indicated interspecific variation in GTX I concentration across all species. GTX I concentrations were consistently higher in leaves compared to petals and nectar. Our findings provide preliminary evidence for phenotypic correlation between GTX I concentrations in defensive tissues (leaves and petals) and floral rewards (nectar), suggesting that Rhododendron species may commonly experience functional trade-offs between herbivore defence and pollinator attraction.
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Affiliation(s)
- Róisín Fattorini
- Department of Life Sciences, Imperial College London, Silwood Park Campus, Ascot, Berkshire, SL5 7PY, UK; Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK.
| | - Paul A Egan
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, PO Box 102, Alnarp 23053, Sweden
| | - James Rosindell
- Department of Life Sciences, Imperial College London, Silwood Park Campus, Ascot, Berkshire, SL5 7PY, UK
| | - Iain W Farrell
- Royal Botanic Gardens, Kew Green, Kew, Richmond, Surrey, TW9 3AE UK
| | - Philip C Stevenson
- Royal Botanic Gardens, Kew Green, Kew, Richmond, Surrey, TW9 3AE UK; Natural Resources Institute, University of Greenwich, Chatham Maritime, Kent, ME4 4TB, UK
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5
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Chen S, Wang Y, Li Y, Zhang X, Wu J. Effects of honeybee ( Apis cerana) visiting behaviour on toxic plant ( Tripterygium hypoglaucum) reproduction. AoB Plants 2022; 14:plac002. [PMID: 35531307 PMCID: PMC9071085 DOI: 10.1093/aobpla/plac002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 04/12/2022] [Indexed: 06/14/2023]
Abstract
Honeybees play a significant role in the plant-pollinator interactions of many flowering plants. The ecological and evolutionary consequences of plant-pollinator interactions vary by geographic region, and the effects of honeybees on the reproduction of toxic plants have not been well studied. We measured the florescence of toxic plants, the flower-visiting behaviour of honeybees and the effects of pollination on the fertility, weight and moisture content of seeds. The effects of climatic factors on the number of flowers, and the spatial and temporal variation in pollinator visits were evaluated, and the effects of pollinator visits on seed quality were evaluated. Flower visitors were diverse, climatic factors had a great impact on spatio-temporal flowering variation and the number of bee visits was strongly correlated with the spatio-temporal variation in the number of flowers. Honeybees strongly increase the fullness and weight of seeds. Our study demonstrated a good ecological fit between the spatio-temporal variation in the flowering of toxic plants and the general validity of honeybee pollination syndrome in the south of Hengduan Mountains in East Asia. A linear relationship between honeybee visitation and plant reproduction can benefit the stabilization of plant reproduction.
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Affiliation(s)
- Shunan Chen
- Institute of Apicultural Research, Chinese Academy of Agricultural Sciences; Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture and Rural Affairs; Key Laboratory of Bee Products for Quality and Safety Control, Ministry of Agriculture and Rural Affairs; Bee Product Quality Supervision and Testing Center, Ministry of Agriculture and Rural Affairs; Beijing 100093, People’s Republic of China
| | - Yunfei Wang
- Committee of Communist Youth League, Yunnan Agricultural University, Kunming 650201, People’s Republic of China
| | - Yi Li
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100093, People’s Republic of China
| | - Xuewen Zhang
- Yunnan Academy of Agricultural Sciences, Kunming 661101, People’s Republic of China
| | - Jie Wu
- Institute of Apicultural Research, Chinese Academy of Agricultural Sciences; Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture and Rural Affairs; Key Laboratory of Bee Products for Quality and Safety Control, Ministry of Agriculture and Rural Affairs; Bee Product Quality Supervision and Testing Center, Ministry of Agriculture and Rural Affairs; Beijing 100093, People’s Republic of China
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6
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Mokkapati JS, Bednarska AJ, Choczyński M, Laskowski R. Toxicokinetics of three insecticides in the female adult solitary bee Osmia bicornis. Environ Pollut 2022; 293:118610. [PMID: 34861333 DOI: 10.1016/j.envpol.2021.118610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 11/12/2021] [Accepted: 11/28/2021] [Indexed: 06/13/2023]
Abstract
The worldwide decline of pollinators is of growing concern and has been related to the use of insecticides. Solitary bees are potentially exposed to many insecticides through contaminated pollen and/or nectar. The kinetics of these compounds in solitary bees is, however, unknown, limiting the use of these important pollinators in pesticide regulations. Here, the toxicokinetics (TK) of chlorpyrifos (as Dursban 480 EC), cypermethrin (Sherpa 100 EC), and acetamiprid (Mospilan 20 SP) was studied for the first time in Osmia bicornis females at sublethal concentrations (near LC20s). The TK of the insecticides was analysed in bees continuously exposed to insecticide-contaminated food in the uptake phase followed by feeding with clean food in the decontamination phase. The TK models differed substantially between the insecticides. Acetamiprid followed the classic one-compartment model with gradual accumulation during the uptake phase followed by depuration during the decontamination phase. Cypermethrin accumulated rapidly in the first two days and then its concentration decreased slowly. Chlorpyrifos accumulated similarly rapidly but no substantial depuration was found until the end of the experiment. Our study demonstrates that some insecticides can harm solitary bees when exposed continuously even at trace concentrations in food because of their constant accumulation leading to time-reinforced toxicity.
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Affiliation(s)
- Jaya Sravanthi Mokkapati
- Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland.
| | - Agnieszka J Bednarska
- Institute of Nature Conservation, Polish Academy of Sciences, Mickiewicza 33, 31-120, Kraków, Poland
| | - Maciej Choczyński
- Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Ryszard Laskowski
- Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
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7
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Barascou L, Brunet JL, Belzunces L, Decourtye A, Henry M, Fourrier J, Le Conte Y, Alaux C. Pesticide risk assessment in honeybees: Toward the use of behavioral and reproductive performances as assessment endpoints. Chemosphere 2021; 276:130134. [PMID: 33690036 DOI: 10.1016/j.chemosphere.2021.130134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 02/18/2021] [Accepted: 02/23/2021] [Indexed: 06/12/2023]
Abstract
The growing gap between new evidence of pesticide toxicity in honeybees and conventional toxicological assays recommended by regulatory test guidelines emphasizes the need to complement current lethal endpoints with sublethal endpoints. In this context, behavioral and reproductive performances have received growing interest since the 2000s, likely due to their ecological relevance and/or the emergence of new technologies. We review the biological interests and methodological measurements of these predominantly studied endpoints and discuss their possible use in the pesticide risk assessment procedure based on their standardization level, simplicity and ecological relevance. It appears that homing flights and reproduction have great potential for pesticide risk assessment, mainly due to their ecological relevance. If exploratory research studies in ecotoxicology have paved the way toward a better understanding of pesticide toxicity in honeybees, the next objective will then be to translate the most relevant behavioral and reproductive endpoints into regulatory test methods. This will require more comparative studies and improving their ecological relevance. This latter goal may be facilitated by the use of population dynamics models for scaling up the consequences of adverse behavioral and reproductive effects from individuals to colonies.
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Affiliation(s)
- Lena Barascou
- INRAE, Abeilles et Environnement, Avignon, France; UMT PrADE, Avignon, France.
| | - Jean-Luc Brunet
- INRAE, Abeilles et Environnement, Avignon, France; UMT PrADE, Avignon, France
| | - Luc Belzunces
- INRAE, Abeilles et Environnement, Avignon, France; UMT PrADE, Avignon, France
| | - Axel Decourtye
- UMT PrADE, Avignon, France; ITSAP-Institut de L'abeille, Avignon, France
| | - Mickael Henry
- INRAE, Abeilles et Environnement, Avignon, France; UMT PrADE, Avignon, France
| | - Julie Fourrier
- UMT PrADE, Avignon, France; ITSAP-Institut de L'abeille, Avignon, France
| | - Yves Le Conte
- INRAE, Abeilles et Environnement, Avignon, France; UMT PrADE, Avignon, France
| | - Cedric Alaux
- INRAE, Abeilles et Environnement, Avignon, France; UMT PrADE, Avignon, France.
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8
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Sonter CA, Rader R, Stevenson G, Stavert JR, Wilson SC. Biological and behavioral responses of European honey bee (Apis mellifera) colonies to perfluorooctane sulfonate exposure. Integr Environ Assess Manag 2021; 17:673-683. [PMID: 33829642 DOI: 10.1002/ieam.4421] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 12/31/2020] [Accepted: 03/29/2021] [Indexed: 06/12/2023]
Abstract
Bees provide pollination services to managed and wild ecosystems but are threatened globally due to multiple stressors, including exposure to contaminants. Perfluorooctane sulfonate (PFOS) is a widely detected and persistent contaminant that accumulates and biomagnifies in food chains. In this exposure effect study, small whole colonies of Apis mellifera (1000 bees) were exposed to PFOS using a purpose-built cage system over a 4-week period. The PFOS exposure concentrations were provided to bees in sugar syrup at concentrations detected in the environment, ranging from 0 to 1.6 mg L-1 . A range of biological and behavioral responses were monitored. Bee tissue, honey, and fecal matter were analyzed using isotope dilution combined with liquid chromatography-tandem mass spectrometry adapted for bee and honey matrix analysis. Bee mortality increased significantly with PFOS exposure at 0.8 mg L-1 or greater, and brood development ceased entirely at 0.02 mg L-1 or greater. Colony activity, temperament, hive maintenance, and defense were adversely affected in all PFOS exposure treatments compared with the control, even at the lowest PFOS exposure of 0.02 mg L-1 . Perfluorooctane sulfonate was detected in bee tissue with a mean bioaccumulation factor of 0.3, and it was also identified in honey and in feces collected from the hive cages. These findings provide the first evidence that PFOS exposure adversely affects honey bee colonies and may transfer to honey. With PFOS contaminating thousands of sites worldwide, our study has implications for exposed bee populations under natural conditions, pollination services, the honey industry, and human health. Integr Environ Assess Manag 2021;17:673-683. © 2021 SETAC.
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Affiliation(s)
- Carolyn A Sonter
- School of Environmental and Rural Science, University of New England, Armidale, New South Wales, Australia
| | - Romina Rader
- School of Environmental and Rural Science, University of New England, Armidale, New South Wales, Australia
| | - Gavin Stevenson
- National Measurement Institute, North Ryde, New South Wales, Australia
| | - Jamie R Stavert
- Department of Conservation, Te Papa Atawhai, Auckland, New Zealand
| | - Susan C Wilson
- School of Environmental and Rural Science, University of New England, Armidale, New South Wales, Australia
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9
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Mokkapati JS, Bednarska AJ, Laskowski R. The development of the solitary bee Osmia bicornis is affected by some insecticide agrochemicals at environmentally relevant concentrations. Sci Total Environ 2021; 775:145588. [PMID: 33611176 DOI: 10.1016/j.scitotenv.2021.145588] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/27/2021] [Accepted: 01/29/2021] [Indexed: 06/12/2023]
Abstract
Solitary bees provide essential pollination services for many arable crops, but are prone to global decline. Agricultural intensification, which is connected with pesticide usage, is among major threats to bees and, thus, to the food security and ecosystem stability. As it may not be possible to cease pesticide usage currently because of the growing demand for food, it is crucial to understand the pesticide toxicities to bees for better protection of pollinator populations. The majority of studies have focused on social bees, and those on solitary bees studied effects of adult exposure, whereas these bees are also likely to be exposed as larvae via the consumption of contaminated pollen. Here, the effects of three commonly used insecticide-based plant protection products on the development of the solitary bee, Osmia bicornis (red mason bee), were studied by exposing larvae to insecticide-contaminated multifloral pollen. The tested insecticides were: Dursban480EC, containing the organophosphate chlorpyrifos (CHP), Sherpa100EC, containing the pyrethroid cypermethrin (CYP), and Mospilan20SP with the neonicotinoid acetamiprid (ACT). When compared to the control larvae fed with uncontaminated-pollen, both CHP and CYP significantly reduced the O. bicornis larval survival and their body mass at all tested concentrations. In contrast, ACT did not affect either larval survival or body mass, but the length of larval stage to cocoon formation was significantly shortened compared to controls. None of studied insecticides affected the mass of cocooned individuals. However, at least 80% of individuals exposed to any of the tested insecticides died before reaching the adult stage, whereas 43% of the controls emerged successfully after overwintering. Although no clear monotonic dose-response relationships were found, our study showed that at least some insecticide formulations affect the development of O. bicornis even at concentrations actually found in pollen in the field, indicating an urgent need for revising current pesticide usage recommendations.
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Affiliation(s)
- Jaya Sravanthi Mokkapati
- Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
| | - Agnieszka J Bednarska
- Institute of Nature Conservation, Polish Academy of Sciences, Mickiewicza 33, 31-120 Kraków, Poland
| | - Ryszard Laskowski
- Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland
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10
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Rossini C, Rodrigo F, Davyt B, Umpiérrez ML, González A, Garrido PM, Cuniolo A, Porrini LP, Eguaras MJ, Porrini MP. Sub-lethal effects of the consumption of Eupatorium buniifolium essential oil in honeybees. PLoS One 2020; 15:e0241666. [PMID: 33147299 PMCID: PMC7641371 DOI: 10.1371/journal.pone.0241666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 10/19/2020] [Indexed: 11/23/2022] Open
Abstract
When developing new products to be used in honeybee colonies, further than acute toxicity, it is imperative to perform an assessment of risks, including various sublethal effects. The long-term sublethal effects of xenobiotics on honeybees, more specifically of acaricides used in honeybee hives, have been scarcely studied, particularly so in the case of essential oils and their components. In this work, chronic effects of the ingestion of Eupatorium buniifolium (Asteraceae) essential oil were studied on nurse honeybees using laboratory assays. Survival, food consumption, and the effect on the composition of cuticular hydrocarbons (CHC) were assessed. CHC were chosen due to their key role as pheromones involved in honeybee social recognition. While food consumption and survival were not affected by the consumption of the essential oil, CHC amounts and profiles showed dose-dependent changes. All groups of CHC (linear and branched alkanes, alkenes and alkadienes) were altered when honeybees were fed with the highest essential oil dose tested (6000 ppm). The compounds that significantly varied include n-docosane, n-tricosane, n-tetracosane, n-triacontane, n-tritriacontane, 9-tricosene, 7-pentacosene, 9-pentacosene, 9-heptacosene, tritriacontene, pentacosadiene, hentriacontadiene, tritriacontadiene and all methyl alkanes. All of them but pentacosadiene were up-regulated. On the other hand, CHC profiles were similar in healthy and Nosema-infected honeybees when diets included the essential oil at 300 and 3000 ppm. Our results show that the ingestion of an essential oil can impact CHC and that the effect is dose-dependent. Changes in CHC could affect the signaling process mediated by these pheromonal compounds. To our knowledge this is the first report of changes in honeybee cuticular hydrocarbons as a result of essential oil ingestion.
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Affiliation(s)
- Carmen Rossini
- Laboratorio de Ecología Química, Facultad de Química, Universidad de la República de Uruguay, Montevideo, Uruguay
- * E-mail:
| | - Federico Rodrigo
- Laboratorio de Ecología Química, Facultad de Química, Universidad de la República de Uruguay, Montevideo, Uruguay
| | - Belén Davyt
- Laboratorio de Ecología Química, Facultad de Química, Universidad de la República de Uruguay, Montevideo, Uruguay
- Centro de Investigación en Abejas Sociales (CIAS), Instituto de Investigaciones en Producción Sanidad y Ambiente (IIPROSAM), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Buenos Aires, Argentina
| | - María Laura Umpiérrez
- Laboratorio de Ecología Química, Facultad de Química, Universidad de la República de Uruguay, Montevideo, Uruguay
- Centro de Investigación en Abejas Sociales (CIAS), Instituto de Investigaciones en Producción Sanidad y Ambiente (IIPROSAM), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Buenos Aires, Argentina
| | - Andrés González
- Laboratorio de Ecología Química, Facultad de Química, Universidad de la República de Uruguay, Montevideo, Uruguay
| | - Paula Melisa Garrido
- Centro de Investigación en Abejas Sociales (CIAS), Instituto de Investigaciones en Producción Sanidad y Ambiente (IIPROSAM), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Buenos Aires, Argentina
| | - Antonella Cuniolo
- Centro de Investigación en Abejas Sociales (CIAS), Instituto de Investigaciones en Producción Sanidad y Ambiente (IIPROSAM), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Buenos Aires, Argentina
| | - Leonardo P. Porrini
- Centro de Investigación en Abejas Sociales (CIAS), Instituto de Investigaciones en Producción Sanidad y Ambiente (IIPROSAM), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Buenos Aires, Argentina
| | - Martín Javier Eguaras
- Centro de Investigación en Abejas Sociales (CIAS), Instituto de Investigaciones en Producción Sanidad y Ambiente (IIPROSAM), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Buenos Aires, Argentina
| | - Martín P. Porrini
- Laboratorio de Ecología Química, Facultad de Química, Universidad de la República de Uruguay, Montevideo, Uruguay
- Centro de Investigación en Abejas Sociales (CIAS), Instituto de Investigaciones en Producción Sanidad y Ambiente (IIPROSAM), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Buenos Aires, Argentina
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11
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Wang F, Yang JF, Wang MY, Jia CY, Shi XX, Hao GF, Yang GF. Graph attention convolutional neural network model for chemical poisoning of honey bees' prediction. Sci Bull (Beijing) 2020; 65:1184-91. [PMID: 36659148 DOI: 10.1016/j.scib.2020.04.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 02/03/2020] [Accepted: 03/24/2020] [Indexed: 01/21/2023]
Abstract
The impact of pesticides on insect pollinators has caused worldwide concern. Both global bee decline and stopping the use of pesticides may have serious consequences for food security. Automated and accurate prediction of chemical poisoning of honey bees is a challenging task owing to a lack of understanding of chemical toxicity and introspection. Deep learning (DL) shows potential utility for general and highly variable tasks across fields. Here, we developed a new DL model of deep graph attention convolutional neural networks (GACNN) with the combination of undirected graph (UG) and attention convolutional neural networks (ACNN) to accurately classify chemical poisoning of honey bees. We used a training dataset of 720 pesticides and an external validation dataset of 90 pesticides, which is one order of magnitude larger than the previous datasets. We tested its performance in two ways: poisonous versus non-poisonous and GACNN versus other frequently-used machine learning models. The first case represents the accuracy in identifying bee poisonous chemicals. The second represents performance advantages. The GACNN achieved ~6% higher performance for predicting toxic samples and more stable with ~7% Matthews Correlation Coefficient (MCC) higher compared to all tested models, demonstrating GACNN is capable of accurately classifying chemicals and has considerable potential in practical applications. In addition, we also summarized and evaluated the mechanisms underlying the response of honey bees to chemical exposure based on the mapping of molecular similarity. Moreover, our cloud platform (http://beetox.cn) of this model provides low-cost universal access to information, which could vitally enhance environmental risk assessment.
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12
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Zeng JY, Wu DD, Shi ZB, Yang J, Zhang GC, Zhang J. Influence of dietary aconitine and nicotine on the gut microbiota of two lepidopteran herbivores. Arch Insect Biochem Physiol 2020; 104:e21676. [PMID: 32323892 DOI: 10.1002/arch.21676] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/12/2020] [Accepted: 03/26/2020] [Indexed: 06/11/2023]
Abstract
The gut microbiota plays an important role in pheromone production, pesticide degradation, vitamin synthesis, and pathogen prevention in the host animal. Therefore, similar to gut morphology and digestive enzyme activity, the gut microbiota may also get altered under plant defensive compound-induced stress. To test this hypothesis, Dendrolimus superans larvae were fed either aconitine- or nicotine-treated fresh leaves of Larix gmelinii, and Lymantria dispar larvae were fed either aconitine- or nicotine-treated fresh leaves of Salix matsudana. Subsequently, the larvae were sampled 72hr after diet administration and DNA extracted from larval enteric canals were employed for gut microbial 16S ribosomal RNA gene sequencing (338 F and 806 R primers). The sequence analysis revealed that dietary nicotine and aconitine influenced the dominant bacteria in the larval gut and determined their abundance. Moreover, the effect of either aconitine or nicotine on D. superans and L. dispar larvae had a greater dependence on insect species than on secondary plant metabolites. These findings further our understanding of the interaction between herbivores and host plants and the coevolution of plants and insects.
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Affiliation(s)
- Jian-Yong Zeng
- Department of Forest Protection, School of Forestry, Northeast Forestry University, Harbin, China
| | - De-Dong Wu
- Department of Forest Protection, School of Forestry, Northeast Forestry University, Harbin, China
| | - Zhong-Bin Shi
- Department of Forest Protection, School of Forestry, Northeast Forestry University, Harbin, China
| | - Jing Yang
- Department of Forest Protection, School of Forestry, Northeast Forestry University, Harbin, China
| | - Guo-Cai Zhang
- Department of Forest Protection, School of Forestry, Northeast Forestry University, Harbin, China
| | - Jie Zhang
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Science, Northeast Forestry University, Harbin, China
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13
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Qi S, Zhu L, Wang D, Wang C, Chen X, Xue X, Wu L. Flumethrin at honey-relevant levels induces physiological stresses to honey bee larvae (Apis mellifera L.) in vitro. Ecotoxicol Environ Saf 2020; 190:110101. [PMID: 31874407 DOI: 10.1016/j.ecoenv.2019.110101] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 12/09/2019] [Accepted: 12/17/2019] [Indexed: 06/10/2023]
Abstract
Varroa mites often inflict heavy losses on the global bee industry and there are few effective control options. Among these methods to control mites, pesticides are extensively used as a cheap, easy to use, and high-efficiency control measure. However, bees are sensitive to many pesticides; thus, a balance between losses induced by drugs and maximum benefits are important for beekeeping and risk assessment. In this study, the effects of flumethrin, a pyrethroid miticide used on bee colonies, was evaluated using bee larvae reared in vitro. We found that flumethrin induced significant mortality during larval metamorphosis and adult emergence. After continuous exposure during the larval stage, significant changes were observed in antioxidative enzymes (SOD and CAT), lipid peroxidation (MDA, LPO, and POD), and detoxification enzymes (GSH, GST, and GR) in the late instar larvae before pupation. It is also noteworthy that flumethrin significantly regulated the expression of immune (Basket and Dscam) and developmental (Amems, Amhex10869, Vtg and Mfe) genes in larvae, which influences can also be found in the subsequent pupae and adult stages. These findings indicate that flumethrin itself is toxic to bee larvae and has potential risks during colony development. Bees are important pollinators and the sustainable and healthy development of colonies is the foundation of pollinating success for agricultural production. This study would provide some useful thinking for pesticides application techniques and processes in risk assessment of pesticides to bee larvae, even colony.
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Affiliation(s)
- Suzhen Qi
- Risk Assessment Laboratory for Bee Products Quality and Safety of the Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing, 100093, China
| | - Lizhen Zhu
- Risk Assessment Laboratory for Bee Products Quality and Safety of the Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing, 100093, China
| | - Donghui Wang
- College of Life Sciences, Peking University, 5 Yiheyuan Road, Beijing, 100871, PR China
| | - Chen Wang
- Chinese Research Academy of Environmental Sciences, Beijing, 10012, PR China
| | - Xiaofeng Chen
- Shenzhen Noposion Agrochemicals Co., Ltd, 113-Tiegang Shuiku Road, Xixiang, Shenzhen, 518102, PR China
| | - Xiaofeng Xue
- Risk Assessment Laboratory for Bee Products Quality and Safety of the Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing, 100093, China
| | - Liming Wu
- Risk Assessment Laboratory for Bee Products Quality and Safety of the Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing, 100093, China.
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14
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Qi S, Niu X, Wang DH, Wang C, Zhu L, Xue X, Zhang Z, Wu L. Flumethrin at sublethal concentrations induces stresses in adult honey bees (Apis mellifera L.). Sci Total Environ 2020; 700:134500. [PMID: 31627045 DOI: 10.1016/j.scitotenv.2019.134500] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 09/10/2019] [Accepted: 09/15/2019] [Indexed: 06/10/2023]
Abstract
Flumethrin is a typical pyrethroid varroacide widely used for mite control in beekeeping worldwide. Currently, information on the toxicological characteristics of flumethrin on bees at sublethal concentrations is still lacking. To fill this gap in information, we performed a 48-h acute oral and 14-day chronic toxicity testing of flumethrin in newly emerged adult honey bees under laboratory conditions. Results showed that flumethrin had high acute toxicity to honey bees with a 48-h LD50 of 0.47 µg/bee (95% CI, 0.39 ∼ 0.57 µg/bee), which is higher than that of many other commercial pyrethroid insecticides, but lower than that of tau-fluvalinate. After 14 days of chronic exposure to flumethrin at 0.01, 0.10, and 1.0 mg/L, significant antioxidant response, detoxification, immune reaction, and apoptosis were observed in the midguts. These findings indicated that flumethrin had potential risks to bees, and it can disturb the homeostasis of bees at sublethal concentrations under longer exposure conditions. Flumethrin is highly lipophilic and easy to accumulate in beeswax; thus, careless practices might pose risks to colony development in commercial beekeeping and native populations. This laboratory study can serve as an early warning, and further studies are required to understand the real residual level of flumethrin in bees and the risks of flumethrin in field condition.
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Affiliation(s)
- Suzhen Qi
- Risk Assessment Laboratory for Bee Products Quaity and Safety of Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China
| | - Xinyue Niu
- Risk Assessment Laboratory for Bee Products Quaity and Safety of Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China; College of Resources and Environment, Henan Institute of Science and Technology, Xinxiang 453000, Henan, China
| | - Dong Hui Wang
- College of Life Sciences, Peking University, 5 Yiheyuan Road, Beijing 100871, PR China
| | - Chen Wang
- Chinese Research Academy of Environmental Sciences, Beijing 10012, China
| | - Lizhen Zhu
- Risk Assessment Laboratory for Bee Products Quaity and Safety of Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China
| | - Xiaofeng Xue
- Risk Assessment Laboratory for Bee Products Quaity and Safety of Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China
| | - Zhongyin Zhang
- College of Resources and Environment, Henan Institute of Science and Technology, Xinxiang 453000, Henan, China
| | - Liming Wu
- Risk Assessment Laboratory for Bee Products Quaity and Safety of Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China.
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15
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Drummond J, Williamson SM, Fitchett AE, Wright GA, Judge SJ. Spontaneous honeybee behaviour is altered by persistent organic pollutants. Ecotoxicology 2017; 26:141-150. [PMID: 27933553 PMCID: PMC5241328 DOI: 10.1007/s10646-016-1749-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 11/20/2016] [Indexed: 06/06/2023]
Abstract
The effect of environmental pollutants on honeybee behaviour has focused mainly on currently used pesticides. However, honeybees are also exposed to persistent organic pollutants (POPs). The aim of this laboratory based study was to determine if exposure to sublethal field-relevant concentrations of POPs altered the spontaneous behaviour of foraging-age worker honeybees. Honeybees (Apis mellifera) were orally exposed to either a sublethal concentration of the polychlorinated biphenyl (PCB) mixture Aroclor 1254 (100 ng/ml), the organochlorine insecticide lindane (2.91 ng/ml) or vehicle (0.01% DMSO, 0.00015% ethanol in 1M sucrose) for 1-4 days. The frequency of single event behaviours and the time engaged in one of four behavioural states (walking, flying, upside down and stationary) were monitored for 15 min after 1, 2, 3 and 4 days exposure. Exposure to Aroclor 1254 but not lindane increased the frequency and time engaged in honeybee motor activity behaviours in comparison to vehicle. The Aroclor 1254-induced hyperactivity was evident after 1 day of exposure and persisted with repeated daily exposure. In contrast, 1 day of exposure to lindane elicited abdominal spasms and increased the frequency of grooming behaviours in comparison to vehicle exposure. After 4 days of exposure, abdominal spasms and increased grooming behaviours were also evident in honeybees exposed to Aroclor 1254. These data demonstrate that POPs can induce distinct behavioural patterns, indicating different toxicokinetic and toxicodynamic properties. The changes in spontaneous behaviour, particularly the PCB-induced chronic hyperactivity and the associated energy demands, may have implications for colony health.
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Affiliation(s)
- Jade Drummond
- Medical Toxicology Centre, Newcastle University, Newcastle upon Tyne, NE2 4AA, UK
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Sally M Williamson
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Ann E Fitchett
- Medical Toxicology Centre, Newcastle University, Newcastle upon Tyne, NE2 4AA, UK
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Geraldine A Wright
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Sarah J Judge
- Medical Toxicology Centre, Newcastle University, Newcastle upon Tyne, NE2 4AA, UK.
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
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16
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Scott-Brown AS, Gregory T, Farrell IW, Stevenson PC. Leaf trichomes and foliar chemistry mediate defence against glasshouse thrips; Heliothrips haemorrhoidalis (Bouché) in Rhododendron simsii. Funct Plant Biol 2016; 43:1170-1182. [PMID: 32480536 DOI: 10.1071/fp16045] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 08/10/2016] [Indexed: 06/11/2023]
Abstract
Herbivore defence mechanisms are a costly diversion of resources away from growth and reproduction. Thus time-limited and tissue specific expression in critical plant parts is more efficient as defined by optimal defence theory. Surprisingly little is known about Rhododendron herbivore defence but it may be mediated by combined chemical and physical mechanisms. Rhododendron simsii Planch. survives cyclic infestations of a leaf-feeding thrips, Heliothrips haemorrhoidalis (Bouché), which severely damage mature leaves but avoid terminal young leaves suggesting specific, localised defence expression. We examined correlations between the distribution of thrips and feeding damage with density of trichomes and the concentration of the diterpenoid, grayanotoxin I, a compound implicated in but not previously reported to mediate invertebrate defence in Rhododendron. Our data show that as leaves matured the number of thrips and area of feeding damage increased as trichome density and grayanotoxin I concentration decreased, this inverse correlation suggesting trichomes and grayanotoxin I mediate defence in younger leaf tissue. Grayanotoxin I was tested against H. haemorrhoidalis and was toxic to immature life stages and repellent to the adult thrips, reducing numbers of first instars emerging on leaves when applied at ecologically relevant concentrations. This work demonstrates that the pattern of defensive traits in foliage of a species of Rhododendron is key to its ability to tolerate cyclic infestations of a generalist herbivore, effectively conserving vital tissues required for growth and reproduction.
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Affiliation(s)
- Alison S Scott-Brown
- Department of Natural Capital and Plant Health, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, UK
| | - Tom Gregory
- UCL Institute of Archaeology, 31-34 Gordon Square, London, WC1H 0PY, UK
| | - Iain W Farrell
- Department of Natural Capital and Plant Health, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, UK
| | - Philip C Stevenson
- Department of Natural Capital and Plant Health, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, UK
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