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Chen R, Yan J, Wickham JD, Gao Y. Genomic identification and evolutionary analysis of chemosensory receptor gene families in two Phthorimaea pest species: insights into chemical ecology and host adaptation. BMC Genomics 2024; 25:493. [PMID: 38762533 PMCID: PMC11102633 DOI: 10.1186/s12864-024-10428-6] [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: 04/01/2024] [Accepted: 05/17/2024] [Indexed: 05/20/2024] Open
Abstract
BACKGROUND Insects rely on sophisticated sensitive chemosensory systems to sense their complex chemical environment. This sensory process involves a combination of odorant receptors (ORs), gustatory receptors (GRs) and ionotropic receptors (IRs) in the chemosensory system. This study focused on the identification and characterization of these three types of chemosensory receptor genes in two closely related Phthorimaea pest species, Phthorimaea operculella (potato tuber moth) and Phthorimaea absoluta (tomato leaf miner). RESULTS Based on manual annotation of the genome, we identified a total of 349 chemoreceptor genes from the genome of P. operculella, including 93 OR, 206 GR and 50 IR genes, while for P. absoluta, we identified 72 OR, 122 GR and 46 IR genes. Through phylogenetic analysis, we observed minimal differences in the number and types of ORs and IRs between the potato tuber moth and tomato leaf miner. In addition, we found that compared with those of tomato leaf miners, the gustatory receptor branch of P. operculella has undergone a large expansion, which may be related to P. absoluta having a narrower host range than P. operculella. Through analysis of differentially expressed genes (DEGs) of male and female antennae, we uncovered 45 DEGs (including 32ORs, 9 GRs, and 4 IRs). CONCLUSIONS Our research provides a foundation for exploring the chemical ecology of these two pests and offers new insights into the dietary differentiation of lepidopteran insects, while simultaneously providing molecular targets for developing environmentally friendly pest control methods based on insect chemoreception.
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Affiliation(s)
- Ruipeng Chen
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Junjie Yan
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Jacob D Wickham
- A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, 119071, Russia
- Department of Entomology, Rutgers University, 93 Lipman Drive, New Brunswick, New Jersey, USA
| | - Yulin Gao
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
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2
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Schreurs M, Piampongsant S, Roncoroni M, Cool L, Herrera-Malaver B, Vanderaa C, Theßeling FA, Kreft Ł, Botzki A, Malcorps P, Daenen L, Wenseleers T, Verstrepen KJ. Predicting and improving complex beer flavor through machine learning. Nat Commun 2024; 15:2368. [PMID: 38531860 DOI: 10.1038/s41467-024-46346-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 02/21/2024] [Indexed: 03/28/2024] Open
Abstract
The perception and appreciation of food flavor depends on many interacting chemical compounds and external factors, and therefore proves challenging to understand and predict. Here, we combine extensive chemical and sensory analyses of 250 different beers to train machine learning models that allow predicting flavor and consumer appreciation. For each beer, we measure over 200 chemical properties, perform quantitative descriptive sensory analysis with a trained tasting panel and map data from over 180,000 consumer reviews to train 10 different machine learning models. The best-performing algorithm, Gradient Boosting, yields models that significantly outperform predictions based on conventional statistics and accurately predict complex food features and consumer appreciation from chemical profiles. Model dissection allows identifying specific and unexpected compounds as drivers of beer flavor and appreciation. Adding these compounds results in variants of commercial alcoholic and non-alcoholic beers with improved consumer appreciation. Together, our study reveals how big data and machine learning uncover complex links between food chemistry, flavor and consumer perception, and lays the foundation to develop novel, tailored foods with superior flavors.
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Affiliation(s)
- Michiel Schreurs
- VIB-KU Leuven Center for Microbiology, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- CMPG Laboratory of Genetics and Genomics, KU Leuven, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- Leuven Institute for Beer Research (LIBR), Gaston Geenslaan 1, B-3001, Leuven, Belgium
| | - Supinya Piampongsant
- VIB-KU Leuven Center for Microbiology, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- CMPG Laboratory of Genetics and Genomics, KU Leuven, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- Leuven Institute for Beer Research (LIBR), Gaston Geenslaan 1, B-3001, Leuven, Belgium
| | - Miguel Roncoroni
- VIB-KU Leuven Center for Microbiology, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- CMPG Laboratory of Genetics and Genomics, KU Leuven, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- Leuven Institute for Beer Research (LIBR), Gaston Geenslaan 1, B-3001, Leuven, Belgium
| | - Lloyd Cool
- VIB-KU Leuven Center for Microbiology, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- CMPG Laboratory of Genetics and Genomics, KU Leuven, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- Leuven Institute for Beer Research (LIBR), Gaston Geenslaan 1, B-3001, Leuven, Belgium
- Laboratory of Socioecology and Social Evolution, KU Leuven, Naamsestraat 59, B-3000, Leuven, Belgium
| | - Beatriz Herrera-Malaver
- VIB-KU Leuven Center for Microbiology, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- CMPG Laboratory of Genetics and Genomics, KU Leuven, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- Leuven Institute for Beer Research (LIBR), Gaston Geenslaan 1, B-3001, Leuven, Belgium
| | - Christophe Vanderaa
- Laboratory of Socioecology and Social Evolution, KU Leuven, Naamsestraat 59, B-3000, Leuven, Belgium
| | - Florian A Theßeling
- VIB-KU Leuven Center for Microbiology, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- CMPG Laboratory of Genetics and Genomics, KU Leuven, Gaston Geenslaan 1, B-3001, Leuven, Belgium
- Leuven Institute for Beer Research (LIBR), Gaston Geenslaan 1, B-3001, Leuven, Belgium
| | - Łukasz Kreft
- VIB Bioinformatics Core, VIB, Rijvisschestraat 120, B-9052, Ghent, Belgium
| | - Alexander Botzki
- VIB Bioinformatics Core, VIB, Rijvisschestraat 120, B-9052, Ghent, Belgium
| | | | - Luk Daenen
- AB InBev SA/NV, Brouwerijplein 1, B-3000, Leuven, Belgium
| | - Tom Wenseleers
- Laboratory of Socioecology and Social Evolution, KU Leuven, Naamsestraat 59, B-3000, Leuven, Belgium
| | - Kevin J Verstrepen
- VIB-KU Leuven Center for Microbiology, Gaston Geenslaan 1, B-3001, Leuven, Belgium.
- CMPG Laboratory of Genetics and Genomics, KU Leuven, Gaston Geenslaan 1, B-3001, Leuven, Belgium.
- Leuven Institute for Beer Research (LIBR), Gaston Geenslaan 1, B-3001, Leuven, Belgium.
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3
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Revell LJ. phytools 2.0: an updated R ecosystem for phylogenetic comparative methods (and other things). PeerJ 2024; 12:e16505. [PMID: 38192598 PMCID: PMC10773453 DOI: 10.7717/peerj.16505] [Citation(s) in RCA: 45] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 10/31/2023] [Indexed: 01/10/2024] Open
Abstract
Phylogenetic comparative methods comprise the general endeavor of using an estimated phylogenetic tree (or set of trees) to make secondary inferences: about trait evolution, diversification dynamics, biogeography, community ecology, and a wide range of other phenomena or processes. Over the past ten years or so, the phytools R package has grown to become an important research tool for phylogenetic comparative analysis. phytools is a diverse contributed R library now consisting of hundreds of different functions covering a variety of methods and purposes in phylogenetic biology. As of the time of writing, phytools included functionality for fitting models of trait evolution, for reconstructing ancestral states, for studying diversification on trees, and for visualizing phylogenies, comparative data, and fitted models, as well numerous other tasks related to phylogenetic biology. Here, I describe some significant features of and recent updates to phytools, while also illustrating several popular workflows of the phytools computational software.
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Affiliation(s)
- Liam J. Revell
- Department of Biology, University of Massachusetts Boston, Boston, MA, USA
- Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Concepción, Chile
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4
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van Neerbos FAC, Dewitte P, Wäckers F, Wenseleers T, Jacquemyn H, Lievens B. Bacterial volatiles elicit differential olfactory responses in insect species from the same and different trophic levels. INSECT SCIENCE 2023; 30:1464-1480. [PMID: 36644938 DOI: 10.1111/1744-7917.13176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 12/18/2022] [Accepted: 12/24/2022] [Indexed: 06/17/2023]
Abstract
Insect communities consist of species from several trophic levels that have to forage for suitable resources among and within larger patches of nonresources. To locate their resources, insects use diverse stimuli, including olfactory, visual, acoustic, tactile and gustatory cues. While most research has focused on cues derived from plants and other insects, there is mounting evidence that insects also respond to volatile organic compounds (VOCs) emitted by microorganisms. However, to date little is known about how the olfactory response of insects within and across different trophic levels is affected by bacterial VOCs. In this study, we used Y-tube bioassays and chemical analysis of VOCs to assess how VOCs emitted by bacteria affect the olfactory response of insects of the same and different trophic levels. Experiments were performed using two aphid species (Amphorophora idaei Börner and Myzus persicae var. nicotianae Blackman), three primary parasitoid species (Aphidius colemani Viereck, A. ervi Haliday, and A. matricariae Viereck), and two hyperparasitoid species (Asaphes suspensus Nees and Dendrocerus aphidum Rondani). Olfactory responses were evaluated for three bacterial strains (Bacillus pumilus ST18.16/133, Curtobacterium sp. ST18.16/085, and Staphylococcus saprophyticus ST18.16/160) that were isolated from the habitat of the insects. Results revealed that insects from all trophic levels responded to bacterial volatiles, but olfactory responses varied between and within trophic levels. All bacteria produced the same set of volatile compounds, but often in different relative concentrations. For 11 of these volatiles we found contrasting correlations between their concentration and the behavior of the primary parasitoids and hyperparasitoids. Furthermore, olfactometer experiments on three of these compounds confirmed the contrasting olfactory responses of primary parasitoids and hyperparasitoids. The potential of these findings for the development of novel semiochemical-based strategies to improve biological aphid control has been discussed.
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Affiliation(s)
- Francine Antoinette Cornelus van Neerbos
- CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department M2S, KU Leuven, Leuven, Belgium
- Leuven Plant Institute (LPI), KU Leuven, Leuven, Belgium
| | - Peter Dewitte
- Laboratory of Socioecology and Social Evolution, Biology Department, KU Leuven, Leuven, Belgium
| | - Felix Wäckers
- Biobest, Westerlo, Belgium
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
| | - Tom Wenseleers
- Laboratory of Socioecology and Social Evolution, Biology Department, KU Leuven, Leuven, Belgium
| | - Hans Jacquemyn
- Leuven Plant Institute (LPI), KU Leuven, Leuven, Belgium
- Laboratory of Plant Conservation and Population Biology, Biology Department, KU Leuven, Leuven, Belgium
| | - Bart Lievens
- CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department M2S, KU Leuven, Leuven, Belgium
- Leuven Plant Institute (LPI), KU Leuven, Leuven, Belgium
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5
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Thomas G, Rusman Q, Morrison WR, Magalhães DM, Dowell JA, Ngumbi E, Osei-Owusu J, Kansman J, Gaffke A, Pagadala Damodaram KJ, Kim SJ, Tabanca N. Deciphering Plant-Insect-Microorganism Signals for Sustainable Crop Production. Biomolecules 2023; 13:997. [PMID: 37371577 PMCID: PMC10295935 DOI: 10.3390/biom13060997] [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: 03/29/2023] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
Agricultural crop productivity relies on the application of chemical pesticides to reduce pest and pathogen damage. However, chemical pesticides also pose a range of ecological, environmental and economic penalties. This includes the development of pesticide resistance by insect pests and pathogens, rendering pesticides less effective. Alternative sustainable crop protection tools should therefore be considered. Semiochemicals are signalling molecules produced by organisms, including plants, microbes, and animals, which cause behavioural or developmental changes in receiving organisms. Manipulating semiochemicals could provide a more sustainable approach to the management of insect pests and pathogens across crops. Here, we review the role of semiochemicals in the interaction between plants, insects and microbes, including examples of how they have been applied to agricultural systems. We highlight future research priorities to be considered for semiochemicals to be credible alternatives to the application of chemical pesticides.
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Affiliation(s)
- Gareth Thomas
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Quint Rusman
- Department of Systematic and Evolutionary Botany, University of Zürich, Zollikerstrasse 107, 8008 Zürich, Switzerland;
| | - William R. Morrison
- United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Center for Grain and Animal Health Research, 1515 College Ave., Manhattan, KS 66502, USA;
| | - Diego M. Magalhães
- Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba 13418-900, SP, Brazil;
| | - Jordan A. Dowell
- Department of Plant Sciences, University of California, Davis, One Shields Ave., Davis, CA 95616, USA;
| | - Esther Ngumbi
- Department of Entomology, University of Illinois at Urbana Champaign, Urbana, IL 61801, USA;
| | - Jonathan Osei-Owusu
- Department of Biological, Physical and Mathematical Sciences, University of Environment and Sustainable Development, Somanya EY0329-2478, Ghana;
| | - Jessica Kansman
- Center for Chemical Ecology, Department of Entomology, The Pennsylvania State University, University Park, PA 16802, USA;
| | - Alexander Gaffke
- United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Center for Medical, Agricultural, and Veterinary Entomology, 6383 Mahan Dr., Tallahassee, FL 32308, USA;
| | | | - Seong Jong Kim
- United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Natural Products Utilization Research Unit, University, MS 38677, USA;
| | - Nurhayat Tabanca
- United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Subtropical Horticulture Research Station, 13601 Old Cutler Rd., Miami, FL 33158, USA
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6
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Colazza S, Peri E, Cusumano A. Chemical Ecology of Floral Resources in Conservation Biological Control. ANNUAL REVIEW OF ENTOMOLOGY 2023; 68:13-29. [PMID: 36130040 DOI: 10.1146/annurev-ento-120220-124357] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Conservation biological control aims to enhance populations of natural enemies of insect pests in crop habitats, typically by intentional provision of flowering plants as food resources. Ideally, these flowering plants should be inherently attractive to natural enemies to ensure that they are frequently visited. We review the chemical ecology of floral resources in a conservation biological control context, with a focus on insect parasitoids. We highlight the role of floral volatiles as semiochemicals that attract parasitoids to the food resources. The discovery that nectar-inhabiting microbes can be hidden players in mediating parasitoid responses to flowering plants has highlighted the complexity of the interactions between plants and parasitoids. Furthermore, because food webs in agroecosystems do not generally stop at the third trophic level, we also consider responses of hyperparasitoids to floral resources. We thus provide an overview of floral compounds as semiochemicals from a multitrophic perspective, and we focus on the remaining questions that need to be addressed to move the field forward.
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Affiliation(s)
- Stefano Colazza
- Department of Agricultural, Food, and Forest Sciences, University of Palermo, Palermo, Italy; , ,
| | - Ezio Peri
- Department of Agricultural, Food, and Forest Sciences, University of Palermo, Palermo, Italy; , ,
| | - Antonino Cusumano
- Department of Agricultural, Food, and Forest Sciences, University of Palermo, Palermo, Italy; , ,
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7
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Almeida OAC, de Araujo NO, Dias BHS, de Sant’Anna Freitas C, Coerini LF, Ryu CM, de Castro Oliveira JV. The power of the smallest: The inhibitory activity of microbial volatile organic compounds against phytopathogens. Front Microbiol 2023; 13:951130. [PMID: 36687575 PMCID: PMC9845590 DOI: 10.3389/fmicb.2022.951130] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 09/20/2022] [Indexed: 01/06/2023] Open
Abstract
Plant diseases caused by phytopathogens result in huge economic losses in agriculture. In addition, the use of chemical products to control such diseases causes many problems to the environment and to human health. However, some bacteria and fungi have a mutualistic relationship with plants in nature, mainly exchanging nutrients and protection. Thus, exploring those beneficial microorganisms has been an interesting and promising alternative for mitigating the use of agrochemicals and, consequently, achieving a more sustainable agriculture. Microorganisms are able to produce and excrete several metabolites, but volatile organic compounds (VOCs) have huge biotechnology potential. Microbial VOCs are small molecules from different chemical classes, such as alkenes, alcohols, ketones, organic acids, terpenes, benzenoids and pyrazines. Interestingly, volatilomes are species-specific and also change according to microbial growth conditions. The interaction of VOCs with other organisms, such as plants, insects, and other bacteria and fungi, can cause a wide range of effects. In this review, we show that a large variety of plant pathogens are inhibited by microbial VOCs with a focus on the in vitro and in vivo inhibition of phytopathogens of greater scientific and economic importance in agriculture, such as Ralstonia solanacearum, Botrytis cinerea, Xanthomonas and Fusarium species. In this scenario, some genera of VOC-producing microorganisms stand out as antagonists, including Bacillus, Pseudomonas, Serratia and Streptomyces. We also highlight the known molecular and physiological mechanisms by which VOCs inhibit the growth of phytopathogens. Microbial VOCs can provoke many changes in these microorganisms, such as vacuolization, fungal hyphal rupture, loss of intracellular components, regulation of metabolism and pathogenicity genes, plus the expression of proteins important in the host response. Furthermore, we demonstrate that there are aspects to investigate by discussing questions that are still not very clear in this research area, especially those that are essential for the future use of such beneficial microorganisms as biocontrol products in field crops. Therefore, we bring to light the great biotechnological potential of VOCs to help make agriculture more sustainable.
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Affiliation(s)
- Octávio Augusto Costa Almeida
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil,Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Natália Oliveira de Araujo
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil,Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Bruno Henrique Silva Dias
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil,Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Carla de Sant’Anna Freitas
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil,Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Luciane Fender Coerini
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil,Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Choong-Min Ryu
- Molecular Phytobacteriology Laboratory, Korea Research Institute of Bioscience & Biotechnology (KRIBB), Daejeon, South Korea,Biosystems and Bioengineering Program, University of Science and Technology, Daejeon, South Korea
| | - Juliana Velasco de Castro Oliveira
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil,Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil,*Correspondence: Juliana Velasco de Castro Oliveira,
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8
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Ai S, Zhang Y, Chen Y, Zhang T, Zhong G, Yi X. Insect-Microorganism Interaction Has Implicates on Insect Olfactory Systems. INSECTS 2022; 13:1094. [PMID: 36555004 PMCID: PMC9787996 DOI: 10.3390/insects13121094] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/23/2022] [Accepted: 11/25/2022] [Indexed: 06/17/2023]
Abstract
Olfaction plays an essential role in various insect behaviors, including habitat selection, access to food, avoidance of predators, inter-species communication, aggregation, and reproduction. The olfactory process involves integrating multiple signals from external conditions and internal physiological states, including living environments, age, physiological conditions, and circadian rhythms. As microorganisms and insects form tight interactions, the behaviors of insects are constantly challenged by versatile microorganisms via olfactory cues. To better understand the microbial influences on insect behaviors via olfactory cues, this paper summarizes three different ways in which microorganisms modulate insect behaviors. Here, we deciphered three interesting aspects of microorganisms-contributed olfaction: (1) How do volatiles emitted by microorganisms affect the behaviors of insects? (2) How do microorganisms reshape the behaviors of insects by inducing changes in the synthesis of host volatiles? (3) How do symbiotic microorganisms act on insects by modulating behaviors?
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Affiliation(s)
- Shupei Ai
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Yuhua Zhang
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Yaoyao Chen
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Tong Zhang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Guohua Zhong
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Xin Yi
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
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9
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Le Sage EH, Ohmer MEB, LaBumbard BC, Altman KA, Reinert LK, Bednark JG, Bletz MC, Inman B, Lindauer A, McDonnell NB, Parker SK, Skerlec SM, Wantman T, Rollins‐Smith LA, Woodhams DC, Voyles J, Richards‐Zawacki CL. Localized carry‐over effects of pond drying on survival, growth, and pathogen defenses in amphibians. Ecosphere 2022. [DOI: 10.1002/ecs2.4224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Emily H. Le Sage
- Department of Pathology, Microbiology and Immunology Vanderbilt University School of Medicine Nashville Tennessee USA
| | - Michel E. B. Ohmer
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | | | - Karie A. Altman
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Laura K. Reinert
- Department of Pathology, Microbiology and Immunology Vanderbilt University School of Medicine Nashville Tennessee USA
| | - Jeffery G. Bednark
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Molly C. Bletz
- Department of Biology University of Massachusetts Boston Massachusetts USA
| | - Brady Inman
- Department of Pathology, Microbiology and Immunology Vanderbilt University School of Medicine Nashville Tennessee USA
- Department of Biology University of Massachusetts Boston Massachusetts USA
| | - Alexa Lindauer
- Department of Biology University of Nevada Reno Nevada USA
| | - Nina B. McDonnell
- Department of Biology University of Massachusetts Boston Massachusetts USA
| | - Sadie K. Parker
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Samantha M. Skerlec
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Trina Wantman
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Louise A. Rollins‐Smith
- Department of Pathology, Microbiology and Immunology Vanderbilt University School of Medicine Nashville Tennessee USA
- Department of Biological Sciences Vanderbilt University Nashville Tennessee USA
- Department of Pediatrics Vanderbilt University School of Medicine Nashville Tennessee USA
| | | | - Jamie Voyles
- Department of Biology University of Nevada Reno Nevada USA
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10
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Cusumano A, Bella P, Peri E, Rostás M, Guarino S, Lievens B, Colazza S. Nectar-Inhabiting Bacteria Affect Olfactory Responses of an Insect Parasitoid by Altering Nectar Odors. MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02078-6. [PMID: 35913610 DOI: 10.1007/s00248-022-02078-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 07/15/2022] [Indexed: 05/28/2023]
Abstract
Floral nectar is ubiquitously colonized by a variety of microorganisms among which yeasts and bacteria are the most common. Microorganisms inhabiting floral nectar can alter several nectar traits, including nectar odor by producing microbial volatile organic compounds (mVOCs). Evidence showing that mVOCs can affect the foraging behavior of insect pollinators is increasing in the literature, whereas the role of mVOCs in altering the foraging behavior of third-trophic level organisms such as insect parasitoids is largely overlooked. Parasitoids are frequent visitors of flowers and are well known to feed on nectar. In this study, we isolated bacteria inhabiting floral nectar of buckwheat, Fagopyrum esculentum (Polygonales: Polygonaceae), to test the hypothesis that nectar bacteria affect the foraging behavior of the egg parasitoid Trissolcus basalis (Hymenoptera: Scelionidae) via changes in odors of nectar. In behavioral assays, we found that T. basalis wasps are attracted toward nectar fermented by 4 out of the 14 bacterial strains isolated, which belong to Staphylococcus epidermidis, Terrabacillus saccharophilus (both Firmicutes), Pantoea sp. (Proteobacteria), and Curtobacterium sp. (Actinobacteria). Results of chemical investigations revealed significant differences in the volatile blend composition of nectars fermented by the bacterial isolates. Our results indicate that nectar-inhabiting bacteria play an important role in the interactions between flowering plants and foraging parasitoids. These results are also relevant from an applied perspective as flowering resources, such as buckwheat, are largely used in agriculture to promote conservation biological control of insect pests.
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Affiliation(s)
- Antonino Cusumano
- Department of Agricultural, Food and Forest Sciences, University of Palermo Viale delle Scienze, Building 5, 90128, Palermo, Italy
- Interuniversity Center for Studies on Bioinspired Agro-Environmental Technology (BATCenter), University of Napoli Federico II, 80055, Portici, Italy
| | - Patrizia Bella
- Department of Agricultural, Food and Forest Sciences, University of Palermo Viale delle Scienze, Building 5, 90128, Palermo, Italy
- Interuniversity Center for Studies on Bioinspired Agro-Environmental Technology (BATCenter), University of Napoli Federico II, 80055, Portici, Italy
| | - Ezio Peri
- Department of Agricultural, Food and Forest Sciences, University of Palermo Viale delle Scienze, Building 5, 90128, Palermo, Italy.
- Interuniversity Center for Studies on Bioinspired Agro-Environmental Technology (BATCenter), University of Napoli Federico II, 80055, Portici, Italy.
| | - Michael Rostás
- Agricultural Entomology, Department of Crop Sciences, University of Göttingen, Grisebachstr. 6, 37077, Göttingen, Germany
| | - Salvatore Guarino
- Institute of Biosciences and Bioresources (IBBR), National Research Council of Italy (CNR), Corso Calatafimi 414, 90129, Palermo, Italy
| | - Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department of Microbial and Molecular Systems, Willem De Croylaan 46, Leuven, KU, 3001, Belgium
- Leuven Plant Institute (LPI), Leuven, KU, 3001, Belgium
| | - Stefano Colazza
- Department of Agricultural, Food and Forest Sciences, University of Palermo Viale delle Scienze, Building 5, 90128, Palermo, Italy
- Interuniversity Center for Studies on Bioinspired Agro-Environmental Technology (BATCenter), University of Napoli Federico II, 80055, Portici, Italy
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11
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Inhibitory Bacterial Diversity and Mucosome Function Differentiate Susceptibility of Appalachian Salamanders to Chytrid Fungal Infection. Appl Environ Microbiol 2022; 88:e0181821. [PMID: 35348389 PMCID: PMC9040618 DOI: 10.1128/aem.01818-21] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Mucosal defenses are crucial in animals for protection against pathogens and predators. Host defense peptides (antimicrobial peptides, AMPs) as well as skin-associated microbes are key components of mucosal immunity, particularly in amphibians. We integrate microbiology, molecular biology, network-thinking, and proteomics to understand how host and microbially derived products on amphibian skin (referred to as the mucosome) serve as pathogen defenses. We studied defense mechanisms against chytrid pathogens, Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), in four salamander species with different Batrachochytrium susceptibilities. Bd infection was quantified using qPCR, mucosome function (i.e., ability to kill Bd or Bsal zoospores in vitro), skin bacterial communities using 16S rRNA gene amplicon sequencing, and the role of Bd-inhibitory bacteria in microbial networks across all species. We explored the presence of candidate-AMPs in eastern newts and red-backed salamanders. Eastern newts had the highest Bd prevalence and mucosome function, while red-back salamanders had the lowest Bd prevalence and mucosome function, and two-lined salamanders and seal salamanders were intermediates. Salamanders with highest Bd infection intensity showed greater mucosome function. Bd infection prevalence significantly decreased as putative Bd-inhibitory bacterial richness and relative abundance increased on hosts. In co-occurrence networks, some putative Bd-inhibitory bacteria were found as hub-taxa, with red-backs having the highest proportion of protective hubs and positive associations related to putative Bd-inhibitory hub bacteria. We found more AMP candidates on salamanders with lower Bd susceptibility. These findings suggest that salamanders possess distinct innate mechanisms that affect chytrid fungi. IMPORTANCE How host mucosal defenses interact, and influence disease outcome is critical in understanding host defenses against pathogens. A more detailed understanding is needed of the interactions between the host and the functioning of its mucosal defenses in pathogen defense. This study investigates the variability of chytrid susceptibility in salamanders and the innate defenses each species possesses to mediate pathogens, thus advancing the knowledge toward a deeper understanding of the microbial ecology of skin-associated bacteria and contributing to the development of bioaugmentation strategies to mediate pathogen infection and disease. This study improves the understanding of complex immune defense mechanisms in salamanders and highlights the potential role of the mucosome to reduce the probability of Bd disease development and that putative protective bacteria may reduce likelihood of Bd infecting skin.
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12
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Dewitte P, Van Kerckvoorde V, Beliën T, Bylemans D, Wenseleers T. Identification of Blackberry ( Rubus fruticosus) Volatiles as Drosophila suzukii Attractants. INSECTS 2021; 12:insects12050417. [PMID: 34066514 PMCID: PMC8148594 DOI: 10.3390/insects12050417] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/28/2021] [Accepted: 05/01/2021] [Indexed: 11/16/2022]
Abstract
The spotted wing drosophila, Drosophila suzukii, is an invasive pest species from Southeast Asia that was recently introduced in Europe and North America. As this fruit fly lays its eggs in ripening soft-skinned fruit, it causes great damage to a variety of crops, including cherries, blueberries, blackberries, raspberries, grapes, plums and strawberries. Consequently, there is a great demand for an effective and species-specific lure, which requires the development of successful attractants. Until now, there is no lure available that is species-specific and can detect the presence of D. suzukii before infestation. As blackberry (Rubus fruticosus) is one of the preferred host crops of D. suzukii, the volatile compounds of R. fruticosus berries are here identified and quantified using multiple headspace SPME (solid phase micro extraction) GC-MS (gas chromatography-mass spectrometry). Subsequently, the attractivity of 33 of the identified compounds was tested with a two-choice laboratory bioassay. Acetaldehyde, hexyl acetate, linalool, myrtenol, L-limonene and camphene came out as significantly attractive to D. suzukii. The first four attractive compounds induced the strongest effect and therefore provided the best prospects to be implemented in a potential lure. These findings could contribute towards the development of more effective attractants for monitoring and mass trapping D. suzukii.
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Affiliation(s)
- Peter Dewitte
- Laboratory of Socioecology and Social Evolution, Department of Biology, KU Leuven, Naamsestraat 59, B-3000 Leuven, Belgium;
- Correspondence:
| | - Vincent Van Kerckvoorde
- Zoology Department, Research Centre for Fruit Cultivation (pcfruit npo), Fruittuinweg 1, B-3800 Sint-Truiden, Belgium; (V.V.K.); (T.B.); (D.B.)
| | - Tim Beliën
- Zoology Department, Research Centre for Fruit Cultivation (pcfruit npo), Fruittuinweg 1, B-3800 Sint-Truiden, Belgium; (V.V.K.); (T.B.); (D.B.)
| | - Dany Bylemans
- Zoology Department, Research Centre for Fruit Cultivation (pcfruit npo), Fruittuinweg 1, B-3800 Sint-Truiden, Belgium; (V.V.K.); (T.B.); (D.B.)
- Department of Biosystems, KU Leuven, Decroylaan 42, B-3001 Heverlee, Belgium
| | - Tom Wenseleers
- Laboratory of Socioecology and Social Evolution, Department of Biology, KU Leuven, Naamsestraat 59, B-3000 Leuven, Belgium;
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13
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Crowley-Gall A, Rering CC, Rudolph AB, Vannette RL, Beck JJ. Volatile microbial semiochemicals and insect perception at flowers. CURRENT OPINION IN INSECT SCIENCE 2021; 44:23-34. [PMID: 33096275 DOI: 10.1016/j.cois.2020.10.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/06/2020] [Accepted: 10/08/2020] [Indexed: 06/11/2023]
Abstract
Many plant-associated microbial communities produce volatile signals that influence insect responses, yet the impact of floral microorganisms has received less attention than other plant microbiomes. Floral microorganisms alter plant and floral odors by adding their own emissions or modifying plant volatiles. These contextual and microbe species-specific changes in floral signaling are detectable by insects and can modify their behavior. Opportunities for future work in floral systems include identifying specific microbial semiochemicals that underlie insect behavioral responses and examining if insect species vary in their responses to microbial volatiles. Examining if documented patterns are consistent across diverse plant-microbe-insect interactions and in realistic plant-based studies will improve our understanding of how microbes mediate pollination interactions in complex system.
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Affiliation(s)
- Amber Crowley-Gall
- Department of Entomology and Nematology, University of California Davis, 43 Briggs Hall, Davis, CA 95616, USA.
| | - Caitlin C Rering
- Chemistry Research Unit, Center for Medical, Agricultural, and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, Gainesville, FL 32608, USA
| | - Arthur B Rudolph
- Chemistry Research Unit, Center for Medical, Agricultural, and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, Gainesville, FL 32608, USA
| | - Rachel L Vannette
- Department of Entomology and Nematology, University of California Davis, 43 Briggs Hall, Davis, CA 95616, USA
| | - John J Beck
- Chemistry Research Unit, Center for Medical, Agricultural, and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, Gainesville, FL 32608, USA
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14
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Winter is coming-Temperature affects immune defenses and susceptibility to Batrachochytrium salamandrivorans. PLoS Pathog 2021; 17:e1009234. [PMID: 33600433 PMCID: PMC7891748 DOI: 10.1371/journal.ppat.1009234] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 12/08/2020] [Indexed: 12/24/2022] Open
Abstract
Environmental temperature is a key factor driving various biological processes, including immune defenses and host-pathogen interactions. Here, we evaluated the effects of environmental temperature on the pathogenicity of the emerging fungal pathogen, Batrachochytrium salamandrivorans (Bsal), using controlled laboratory experiments, and measured components of host immune defense to identify regulating mechanisms. We found that adult and juvenile Notophthalmus viridescens died faster due to Bsal chytridiomycosis at 14°C than at 6 and 22°C. Pathogen replication rates, total available proteins on the skin, and microbiome composition likely drove these relationships. Temperature-dependent skin microbiome composition in our laboratory experiments matched seasonal trends in wild N. viridescens, adding validity to these results. We also found that hydrophobic peptide production after two months post-exposure to Bsal was reduced in infected animals compared to controls, perhaps due to peptide release earlier in infection or impaired granular gland function in diseased animals. Using our temperature-dependent susceptibility results, we performed a geographic analysis that revealed N. viridescens populations in the northeastern United States and southeastern Canada are at greatest risk for Bsal invasion, which shifted risk north compared to previous assessments. Our results indicate that environmental temperature will play a key role in the epidemiology of Bsal and provide evidence that temperature manipulations may be a viable disease management strategy. In 2010, a new skin-eating fungus, Batrachochytrium salamandrivorans (Bsal), was discovered killing salamanders in the Netherlands. Since then, the pathogen has spread to other European countries. Bsal is believed to be from Asia and is being translocated through the international trade of amphibians. To our knowledge, Bsal has not arrived to North America. As a proactive strategy for disease control, we evaluated how a range of environmental temperatures in North America could affect invasion risk of Bsal into a widely distributed salamander species, the eastern newt (Notophthalmus viridescens). Our results show that northeastern USA, southeastern Canada, and the higher elevations of the Appalachian Mountains have the greatest likelihood of Bsal invasion, when temperature-dependent susceptibility is included in risk analyses. Changes in eastern newt susceptibility to Bsal infection associated with temperature are likely an interaction between pathogen replication rate and host immune defenses, including changes in skin microbiome composition and the host’s ability to produce Bsal-killing proteins on the skin. Our study provides new insights into how latitude, elevation and season can impact the epidemiology of Bsal, and suggests that strategies that manipulate microclimate of newt habitats could be useful in managing Bsal outbreaks and that climate change will impact Bsal invasion probability.
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15
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Goelen T, Vuts J, Sobhy IS, Wäckers F, Caulfield JC, Birkett MA, Rediers H, Jacquemyn H, Lievens B. Identification and application of bacterial volatiles to attract a generalist aphid parasitoid: from laboratory to greenhouse assays. PEST MANAGEMENT SCIENCE 2021; 77:930-938. [PMID: 32975888 DOI: 10.1002/ps.6102] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 08/25/2020] [Accepted: 09/25/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Recent studies have shown that microorganisms emit volatile compounds that affect insect behaviour. However, it remains largely unclear whether microbes can be exploited as a source of attractants to improve biological control of insect pests. In this study, we used a combination of coupled gas chromatography-electroantennography (GC-EAG) and Y-tube olfactometer bioassays to identify attractive compounds in the volatile extracts of three bacterial strains that are associated with the habitat of the generalist aphid parasitoid Aphidius colemani, and to create mixtures of synthetic compounds to find attractive blends for A. colemani. Subsequently, the most attractive blend was evaluated in two-choice cage experiments under greenhouse conditions. RESULTS GC-EAG analysis revealed 20 compounds that were linked to behaviourally attractive bacterial strains. A mixture of two EAG-active compounds, styrene and benzaldehyde applied at a respective dose of 1 μg and 10 ng, was more attractive than the single compounds or the culture medium of the bacteria in Y-tube olfactometer bioassays. Application of this synthetic mixture under greenhouse conditions resulted in significant attraction of the parasitoids, and outperformed application of the bacterial culture medium. CONCLUSION Compounds isolated from bacterial blends were capable of attracting parasitoids both in laboratory and greenhouse assays, indicating that microbial cultures are an effective source of insect attractants. This opens new opportunities to attract and retain natural enemies of pest species and to enhance biological pest control.
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Affiliation(s)
- Tim Goelen
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Centre of Microbial and Plant Genetics (CMPG), Department of Microbial and Molecular Systems (M2S), Leuven, Belgium
| | - József Vuts
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, UK
| | - Islam S Sobhy
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Centre of Microbial and Plant Genetics (CMPG), Department of Microbial and Molecular Systems (M2S), Leuven, Belgium
- Department of Plant Protection, Faculty of Agriculture, Suez Canal University, Ismailia, Egypt
| | - Felix Wäckers
- Biobest, Westerlo, Belgium
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
| | - John C Caulfield
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, UK
| | - Michael A Birkett
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, UK
| | - Hans Rediers
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Centre of Microbial and Plant Genetics (CMPG), Department of Microbial and Molecular Systems (M2S), Leuven, Belgium
| | - Hans Jacquemyn
- Laboratory of Plant Conservation and Population Biology, Biology Department, KU Leuven, Leuven, Belgium
| | - Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Centre of Microbial and Plant Genetics (CMPG), Department of Microbial and Molecular Systems (M2S), Leuven, Belgium
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16
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Le Sage EH, LaBumbard BC, Reinert LK, Miller BT, Richards-Zawacki CL, Woodhams DC, Rollins-Smith LA. Preparatory immunity: Seasonality of mucosal skin defences and Batrachochytrium infections in Southern leopard frogs. J Anim Ecol 2020; 90:542-554. [PMID: 33179786 DOI: 10.1111/1365-2656.13386] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 10/28/2020] [Indexed: 12/14/2022]
Abstract
Accurately predicting the impacts of climate change on wildlife health requires a deeper understanding of seasonal rhythms in host-pathogen interactions. The amphibian pathogen, Batrachochytrium dendrobatidis (Bd), exhibits seasonality in incidence; however, the role that biological rhythms in host defences play in defining this pattern remains largely unknown. The aim of this study was to examine whether host immune and microbiome defences against Bd correspond with infection risk and seasonal fluctuations in temperature and humidity. Over the course of a year, five populations of Southern leopard frogs (Rana [Lithobates] sphenocephala) in Tennessee, United States, were surveyed for host immunity, microbiome and pathogen dynamics. Frogs were swabbed for pathogen load and skin bacterial diversity and stimulated to release stored antimicrobial peptides (AMPs). Secretions were analysed to estimate total hydrophobic peptide concentrations, presence of known AMPs and effectiveness of Bd growth inhibition in vitro. The diversity and proportion of bacterial reads with a 99% match to sequences of isolates known to inhibit Bd growth in vitro were used as an estimate of predicted anti-Bd function of the skin microbiome. Batrachochytrium dendrobatidis dynamics followed the expected seasonal fluctuations-peaks in cooler months-which coincided with when host mucosal defences were most potent against Bd. Specifically, the concentration and expression of stored AMPs cycled synchronously with Bd dynamics. Although microbiome changes followed more linear trends over time, the proportion of bacteria that can function to inhibit Bd growth was greatest when risk of Bd infection was highest. We interpret the increase in peptide storage in the fall and the shift to a more anti-Bd microbiome over winter as a preparatory response for subsequent infection risk during the colder periods when AMP synthesis and bacterial growth is slow and pathogen pressure from this cool-adapted fungus is high. Given that a decrease in stored AMP concentrations as temperatures warm in spring likely means greater secretion rates, the subsequent decrease in prevalence suggests seasonality of Bd in this host may be in part regulated by annual immune rhythms, and dominated by the effects of temperature.
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Affiliation(s)
- Emily H Le Sage
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | | | - Laura K Reinert
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Brian T Miller
- Department of Biology, Middle Tennessee State University, Murfreesboro, TN, USA
| | | | - Doug C Woodhams
- Department of Biology, University of Massachusetts, Boston, MA, USA
| | - Louise A Rollins-Smith
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA.,Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA.,Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, USA
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