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Sobhy IS, Gurr GM, Hefin Jones T. Induced plant resistance and its influence on natural enemy use of plant-derived foods. CURRENT OPINION IN INSECT SCIENCE 2024; 64:101218. [PMID: 38838913 DOI: 10.1016/j.cois.2024.101218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 05/28/2024] [Accepted: 05/30/2024] [Indexed: 06/07/2024]
Abstract
In response to herbivory, plants employ several inducible defenses to mitigate herbivore damage. These plant-induced responses can trigger subtle changes in plant metabolite composition, altering the profiles of plant-produced exudates such as (extra-) floral nectar and plant guttation. Natural enemies consume these plant-produced exudates, which serve as consistent and nutrient-dense food sources. There is mounting evidence that natural enemies' access to plant-produced exudates impacts their fitness, performance, and life history traits. Nonetheless, the role of induced plant defense on plant-produced exudates and the subsequent effect on natural enemies remains under-researched. This review, thus, highlights the potential role of induced plant defense on the profiles of plant-produced exudates, with a particular emphasis on altered metabolic changes affecting resource nutritional value and consequently the fitness and performance of natural enemies. Future directions and potential implications in biological control practices are also highlighted.
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Affiliation(s)
- Islam S Sobhy
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK.
| | - Geoff M Gurr
- Gulbali Institute, Charles Sturt University, Leeds Parade, Orange NSW 2800, Australia
| | - T Hefin Jones
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
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2
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Sobhy IS, Berry C. Chemical ecology of nectar-mosquito interactions: recent advances and future directions. CURRENT OPINION IN INSECT SCIENCE 2024; 63:101199. [PMID: 38588943 DOI: 10.1016/j.cois.2024.101199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 04/03/2024] [Accepted: 04/03/2024] [Indexed: 04/10/2024]
Abstract
Mosquitoes, males and females, rely on sugar-rich resources, including floral nectar as a primary source of sugar to meet their energy and nutritional needs. Despite advancements in understanding mosquito host-seeking and blood-feeding preferences, significant gaps in our knowledge of the chemical ecology mediating mosquito-nectar associations remain. The influence of such association with nectar on mosquito behavior and the resulting effects on their fitness are also not totally understood. It is significant that floral nectar frequently acts as a natural habitat for various microbes (e.g. bacteria and yeast), which substantially alter nectar characteristics, influencing the nutritional ecology of flower-visiting insects, such as mosquitoes. The role of nectar-inhabiting microbes in shaping the nectar-mosquito interactions remains, however, under-researched. This review explores recent advances in understanding the role of such multitrophic interactions on the fitness and life history traits of mosquitoes and outlines future directions for research toward their control as disease vectors.
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Affiliation(s)
- Islam S Sobhy
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK.
| | - Colin Berry
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
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3
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Rering CC, Rudolph AB, Li QB, Read QD, Muñoz PR, Ternest JJ, Hunter CT. A quantitative survey of the blueberry (Vaccinium spp.) culturable nectar microbiome: variation between cultivars, locations, and farm management approaches. FEMS Microbiol Ecol 2024; 100:fiae020. [PMID: 38366934 PMCID: PMC10903978 DOI: 10.1093/femsec/fiae020] [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: 08/01/2023] [Revised: 01/25/2024] [Accepted: 02/15/2024] [Indexed: 02/19/2024] Open
Abstract
Microbes in floral nectar can impact both their host plants and floral visitors, yet little is known about the nectar microbiome of most pollinator-dependent crops. In this study, we examined the abundance and composition of the fungi and bacteria inhabiting Vaccinium spp. nectar, as well as nectar volume and sugar concentrations. We compared wild V. myrsinites with two field-grown V. corymbosum cultivars collected from two organic and two conventional farms. Differences in nectar traits and microbiomes were identified between V. corymbosum cultivars but not Vaccinium species. The microbiome of cultivated plants also varied greatly between farms, whereas management regime had only subtle effects, with higher fungal populations detected under organic management. Nectars were hexose-dominant, and high cell densities were correlated with reduced nectar sugar concentrations. Bacteria were more common than fungi in blueberry nectar, although both were frequently detected and co-occurred more often than would be predicted by chance. "Cosmopolitan" blueberry nectar microbes that were isolated in all plants, including Rosenbergiella sp. and Symmetrospora symmetrica, were identified. This study provides the first systematic report of the blueberry nectar microbiome, which may have important implications for pollinator and crop health.
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Affiliation(s)
- Caitlin C Rering
- Chemistry Research Unit, Center for Medical, Agricultural and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, 1700 SW 23rd Dr, Gainesville, FL 32608, United States
| | - Arthur B Rudolph
- Chemistry Research Unit, Center for Medical, Agricultural and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, 1700 SW 23rd Dr, Gainesville, FL 32608, United States
| | - Qin-Bao Li
- Chemistry Research Unit, Center for Medical, Agricultural and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, 1700 SW 23rd Dr, Gainesville, FL 32608, United States
| | - Quentin D Read
- Agricultural Research Service, Southeast Area, United States Department of Agriculture, 840 Oval Drive, Raleigh, NC 27606, United States
| | - Patricio R Muñoz
- Horticultural Sciences Department, University of Florida, 2550 Hull Rd, Gainesville, FL 32611, United States
| | - John J Ternest
- Department of Entomology and Nematology, University of Florida, 1881 Natural Area Dr, Gainesville, FL 32611, United States
| | - Charles T Hunter
- Chemistry Research Unit, Center for Medical, Agricultural and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, 1700 SW 23rd Dr, Gainesville, FL 32608, United States
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4
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Wilberts L, Vuts J, Caulfield JC, Thomas G, Withall DM, Wäckers F, Birkett MA, Jacquemyn H, Lievens B. Effects of root inoculation of entomopathogenic fungi on olfactory-mediated behavior and life-history traits of the parasitoid Aphidius ervi (Haliday) (Hymenoptera: Braconidae). PEST MANAGEMENT SCIENCE 2024; 80:307-316. [PMID: 37682693 DOI: 10.1002/ps.7762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 08/23/2023] [Accepted: 09/08/2023] [Indexed: 09/10/2023]
Abstract
BACKGROUND Although most biological control programs use multiple biological agents to manage pest species, to date only a few programs have combined the use of agents from different guilds. Using sweet pepper (Capsicum annuum L.), the entomopathogenic fungus Akanthomyces muscarius ARSEF 5128, the tobacco peach aphid Myzus persicae var. nicotianae and the aphid parasitoid Aphidius ervi as the experimental model, we explored whether root inoculation with an entomopathogenic fungus is compatible with parasitoid wasps for enhanced biocontrol of aphids. RESULTS In dual-choice behavior experiments, A. ervi was significantly attracted to the odor of M. persicae-infested C. annuum plants that had been inoculated with A. muscarius, compared to noninoculated infested plants. There was no significant difference in attraction to the odor of uninfested plants. Myzus persicae-infested plants inoculated with A. muscarius emitted significantly higher amounts of indole, (E)-nerolidol, (3E,7E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene and one unidentified terpene compared to noninoculated infested plants. Coupled gas chromatography-electroantennography, using the antennae of A. ervi, confirmed the physiological activity of these elevated compounds. Inoculation of plants with A. muscarius did not affect parasitism rate nor parasitoid longevity, but significantly increased the speed of mummy formation in parasitized aphids on fungus-inoculated plants. CONCLUSION Our data suggest that root inoculation of C. annuum with A. muscarius ARSEF 5128 alters the olfactory-mediated behavior of parasitoids, but has little effect on parasitism efficiency or life-history parameters. However, increased attraction of parasitoids towards M. persicae-infested plants when inoculated by entomopathogenic fungi can accelerate host localization and hence improve biocontrol efficacy. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Liesbet Wilberts
- CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, KU Leuven, Leuven, Belgium
- Leuven Plant Institute, KU Leuven, Leuven, Belgium
| | - József Vuts
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, UK
| | - John C Caulfield
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, UK
| | - Gareth Thomas
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, UK
| | - David M Withall
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, UK
| | - Felix Wäckers
- Biobest, Westerlo, Belgium
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
| | - Michael A Birkett
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, UK
| | - Hans Jacquemyn
- Leuven Plant Institute, 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, Department of Microbial and Molecular Systems, KU Leuven, Leuven, Belgium
- Leuven Plant Institute, KU Leuven, Leuven, Belgium
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5
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Álvarez-Pérez S, Lievens B, de Vega C. Floral nectar and honeydew microbial diversity and their role in biocontrol of insect pests and pollination. CURRENT OPINION IN INSECT SCIENCE 2024; 61:101138. [PMID: 37931689 DOI: 10.1016/j.cois.2023.101138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 10/29/2023] [Accepted: 10/30/2023] [Indexed: 11/08/2023]
Abstract
Sugar-rich plant-related secretions, such as floral nectar and honeydew, that are commonly used as nutrient sources by insects and other animals, are also the ecological niche for diverse microbial communities. Recent research has highlighted the great potential of nectar and honeydew microbiomes in biological pest control and improved pollination, but the exploitation of these microbiomes requires a deep understanding of their community dynamics and plant-microbe-insect interactions. Additionally, the successful application of microbes in crop fields is conditioned by diverse ecological, legal, and ethical challenges that should be taken into account. In this article, we provide an overview of the nectar and honeydew microbiomes and discuss their potential applications in sustainable agricultural practices.
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Affiliation(s)
- Sergio Álvarez-Pérez
- Department of Animal Health, Complutense University of Madrid, 28040 Madrid, Spain.
| | - Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department of Microbial and Molecular Systems, KU Leuven, B-3001 Heverlee, Belgium
| | - Clara de Vega
- Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, 41012 Sevilla, Spain
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6
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Dötterl S, Gershenzon J. Chemistry, biosynthesis and biology of floral volatiles: roles in pollination and other functions. Nat Prod Rep 2023; 40:1901-1937. [PMID: 37661854 DOI: 10.1039/d3np00024a] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Covering: 2010 to 2023Floral volatiles are a chemically diverse group of plant metabolites that serve multiple functions. Their composition is shaped by environmental, ecological and evolutionary factors. This review will summarize recent advances in floral scent research from chemical, molecular and ecological perspectives. It will focus on the major chemical classes of floral volatiles, on notable new structures, and on recent discoveries regarding the biosynthesis and the regulation of volatile emission. Special attention will be devoted to the various functions of floral volatiles, not only as attractants for different types of pollinators, but also as defenses of flowers against enemies. We will also summarize recent findings on how floral volatiles are affected by abiotic stressors, such as increased temperatures and drought, and by other organisms, such as herbivores and flower-dwelling microbes. Finally, this review will indicate current research gaps, such as the very limited knowledge of the isomeric pattern of chiral compounds and its importance in interspecific interactions.
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Affiliation(s)
- Stefan Dötterl
- Department of Environment & Biodiversity, Paris Lodron University Salzburg, Hellbrunnerstr 34, 5020 Salzburg, Austria.
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany.
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7
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Cusumano A, Lievens B. Microbe-mediated alterations in floral nectar: consequences for insect parasitoids. CURRENT OPINION IN INSECT SCIENCE 2023; 60:101116. [PMID: 37741616 DOI: 10.1016/j.cois.2023.101116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 09/11/2023] [Accepted: 09/14/2023] [Indexed: 09/25/2023]
Abstract
Floral nectar is frequently colonized by microbes among which bacteria and yeasts are the most abundant. These microbes have the ability to alter nectar characteristics with consequences for the whole community of flower-visiting insects. Recent research carried out on natural enemies of insect herbivores has shown that microbe-mediated changes in nectar traits can influence the foraging behavior and life history traits of parasitoids. The production of microbial volatile organic compounds can affect the attraction of parasitoids to nectar, while changes in sugar and amino acid composition can impact their longevity. Future research should focus on understanding the effects of nectar microbial colonization on parasitoid reproduction, with a specific emphasis on the interactions among different microbial taxa known to co-occur in floral nectar. Overall, this review highlights the importance of considering the role of nectar-inhabiting microbes in shaping the interactions between parasitoids and their food resources.
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Affiliation(s)
- Antonino Cusumano
- Department of Agricultural, Food, and Forest Sciences, University of Palermo, 90128 Palermo, Italy.
| | - Bart Lievens
- Department of Microbial and Molecular Systems, KU Leuven, B-3001 Leuven, Belgium
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8
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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 DOI: 10.3390/biom13060997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 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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9
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Liu D, Smagghe G, Liu TX. Interactions between Entomopathogenic Fungi and Insects and Prospects with Glycans. J Fungi (Basel) 2023; 9:jof9050575. [PMID: 37233286 DOI: 10.3390/jof9050575] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/27/2023] Open
Abstract
Concerns regarding the ecological and health risks posed by synthetic insecticides have instigated the exploration of alternative methods for controlling insects, such as entomopathogenic fungi (EPF) as biocontrol agents. Therefore, this review discusses their use as a potential alternative to chemical insecticides and especially focuses on the two major ones, Beauveria bassiana and Metarhizium anisopliae, as examples. First, this review exemplifies how B. bassiana- and M. anisopliae-based biopesticides are used in the world. Then, we discuss the mechanism of action by which EPF interacts with insects, focusing on the penetration of the cuticle and the subsequent death of the host. The interactions between EPF and the insect microbiome, as well as the enhancement of the insect immune response, are also summarized. Finally, this review presents recent research that N-glycans may play a role in eliciting an immune response in insects, resulting in the increased expression of immune-related genes and smaller peritrophic matrix pores, reducing insect midgut permeability. Overall, this paper provides an overview of the EPF in insect control and highlights the latest developments relating to the interaction between fungi and insect immunity.
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Affiliation(s)
- Dongdong Liu
- Institute of Entomology, Guizhou University, Guiyang 550025, China
- Institute of Plant Health and Medicine, Guizhou University, Guiyang 550025, China
| | - Guy Smagghe
- Institute of Entomology, Guizhou University, Guiyang 550025, China
- Institute of Plant Health and Medicine, Guizhou University, Guiyang 550025, China
| | - Tong-Xian Liu
- Institute of Entomology, Guizhou University, Guiyang 550025, China
- Institute of Plant Health and Medicine, Guizhou University, Guiyang 550025, China
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10
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Pekas A, Tena A, Peri E, Colazza S, Cusumano A. Competitive interactions in insect parasitoids: effects of microbial symbionts across tritrophic levels. CURRENT OPINION IN INSECT SCIENCE 2023; 55:101001. [PMID: 36494029 DOI: 10.1016/j.cois.2022.101001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 11/30/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
Competition for hosts is a common ecological interaction in insect parasitoids. In the recent years, it has become increasingly evident that microorganisms can act as 'hidden players' in parasitoid ecology. In this review, we propose that parasitoid competition should take into consideration the microbial influence. In particular, we take a tritrophic perspective and discuss how parasitoid competition can be modulated by microorganisms associated with the parasitoids, their herbivore hosts, or the plants attacked by the herbivores. Although research is still in its infancy, recent studies have shown that microbial symbionts can modulate the contest outcome. The emerging pattern is that microorganisms not only affect the competitive traits of parasitoids but also the fighting arena (i.e. the herbivore host and its food plant), in which competition takes place. We have also identified important gaps in the literature that should be addressed in future studies to advance our understanding about parasitoid competition.
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Affiliation(s)
| | - Alejandro Tena
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - Ezio Peri
- Department of Agricultural, Food, and Forest Sciences, University of Palermo, Palermo, Italy
| | - Stefano Colazza
- 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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11
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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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12
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Niu J, Li X, Zhang S, Yao Y, Zhang Y, Liu Y, Peng X, Huang J, Peng F. Identification and functional studies of microbial volatile organic compounds produced by Arctic flower yeasts. FRONTIERS IN PLANT SCIENCE 2023; 13:941929. [PMID: 36684747 PMCID: PMC9850290 DOI: 10.3389/fpls.2022.941929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 11/29/2022] [Indexed: 06/17/2023]
Abstract
Microbial volatile organic compounds (mVOCs) can serve as a communication channel among microorganisms, insects and plants, making them important in ecosystem. In order to understand the possible role of mVOCs in Arctic ecology, the microbes in Arctic flowers and their mVOCs and effects on plants were investigated. This study aims to isolate different yeast species from the flowers of five Arctic plant species and further to explore the function of mVOCs emitted by these microbes to plant. It was found that the composition and amount of mVOCs produced by the isolated yeasts were considerably affected by changes in incubation temperature. When the incubation temperature rose, the species of alcohols, aldehydes, esters, organic acids, and ketones increased, but substances specific to low temperature decreased or disappeared. When yeasts were co-cultured with Arabidopsis thaliana without any direct contact, mVOCs produced by the isolated yeasts inhibited the seed germination of A. thaliana at low temperatures; however, the mVOCs promoted the chlorophyll content, fresh weight, root weight and flowering rate of Arabidopsis plants. Although the overall growth-promoting effect of yeast mVOCs was higher at 20°C than at 10°C, the growth-promoting effect on roots, flowers and chlorophyll was highest at 10°C. When cultured at 10°C, the mVOCs produced by Cystofilobasidium capitatum A37, Cryptococcus sp. D41, and Sporidiobolus salmonicolor D27 had the highest growth-promoting effects on the root, flowering rate and chlorophyll content of Arabidopsis, respectively. In the co-culture system, some new mVOCs were detected, such as hendecane, tetradecane, and 1-hexanol that have been proven to promote plant growth. In addition, mVOCs of the isolated Arctic yeasts could inhibit the growth of several microorganisms, especially filamentous fungi. It was the first time to prove that mVOCs produced by the isolated yeasts had varying effects on plant growth at different incubating temperatures, providing a reference for the interactions between microorganisms and plants and their possible responses to climate change in the Arctic area. Moreover, the characteristics of promoting plant growth and inhibiting microbial growth by mVOCs of Arctic yeasts would lay a foundation for potential applications in the future.
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Affiliation(s)
- Jingjing Niu
- China Center for Type Culture Collection (CCTCC), College of Life Sciences, Wuhan University, Wuhan, China
| | - Xuhuan Li
- China Center for Type Culture Collection (CCTCC), College of Life Sciences, Wuhan University, Wuhan, China
| | - Siyu Zhang
- China Center for Type Culture Collection (CCTCC), College of Life Sciences, Wuhan University, Wuhan, China
| | - Yifeng Yao
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Yongping Zhang
- China Center for Type Culture Collection (CCTCC), College of Life Sciences, Wuhan University, Wuhan, China
| | - Yixuan Liu
- China Center for Type Culture Collection (CCTCC), College of Life Sciences, Wuhan University, Wuhan, China
| | - Xiaoya Peng
- China Center for Type Culture Collection (CCTCC), College of Life Sciences, Wuhan University, Wuhan, China
| | - Jun Huang
- China Center for Type Culture Collection (CCTCC), College of Life Sciences, Wuhan University, Wuhan, China
| | - Fang Peng
- China Center for Type Culture Collection (CCTCC), College of Life Sciences, Wuhan University, Wuhan, China
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Davis TS, Stewart JE, Clark C, Van Buiten C. Nutritional Profile and Ecological Interactions of Yeast Symbionts Associated with North American Spruce Beetle (Dendroctonus rufipennis). MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02158-7. [PMID: 36542127 DOI: 10.1007/s00248-022-02158-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 12/08/2022] [Indexed: 06/17/2023]
Abstract
To better understand functional ecology of bark beetle-microbial symbioses, we characterized yeast associates of North American spruce beetle (Dendroctous rufipennis Kirby) across populations. Seven yeast species were detected; Wickerhamomyces canadensis (Wickerham) Kurtzman et al. (Sachharomycetales: Saccharomycetaceae) was the most common (74% of isolates) and found in all populations. Isolates of W. canadensis were subsequently tested for competitive interactions with symbiotic (Leptographium abietinum, = Grosmannia abietina) and pathogenic (Beauvaria bassiana) filamentous fungi, and isolates were nutritionally profiled (protein and P content). Exposure to yeast headspace emissions had isolate-dependent effects on colony growth of symbiotic and pathogenic fungi; most isolates of W. canadensis slightly inhibited growth rates of symbiotic (L. abietinum, mean effect: - 4%) and entomopathogenic (B. bassiana, mean effect: - 6%) fungi. However, overall variation was high (range: - 35.4 to + 88.6%) and some yeasts enhanced growth of filamentous fungi whereas others were consistently inhibitory. The volatile 2-phenylethanol was produced by W. canadensis and synthetic 2-phenylethanol reduced growth rates of both L. abietinum and B. bassiana by 36% on average. Mean protein and P content of Wickerhamomyces canadensis cultures were 0.8% and 7.2%, respectively, but isolates varied in nutritional content and protein content was similar to that of host tree phloem. We conclude that W. canadensis is a primary yeast symbiont of D. rufipennis in the Rocky Mountains and emits volatiles that can affect growth of associated microbes. Wickerhamomyces canadensis isolates vary substantially in limiting nutrients (protein and P), but concentrations are less than reported for the symbiotic filamentous fungus L. abietinum.
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Affiliation(s)
- Thomas S Davis
- Forest & Rangeland Stewardship, Warner College of Natural Resources, Colorado State University, Fort Collins, USA.
- Graduate Degree Program in Ecology, Colorado State University, Fort Collins, USA.
| | - Jane E Stewart
- Graduate Degree Program in Ecology, Colorado State University, Fort Collins, USA
- Agricultural Biology, College of Agricultural Sciences, Colorado State University, Fort Collins, USA
| | - Caitlin Clark
- Food Science and Human Nutrition, College of Health and Human Sciences, Colorado State University, Fort Collins, USA
| | - Charlene Van Buiten
- Food Science and Human Nutrition, College of Health and Human Sciences, Colorado State University, Fort Collins, USA
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14
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Fenner ED, Scapini T, da Costa Diniz M, Giehl A, Treichel H, Álvarez-Pérez S, Alves SL. Nature's Most Fruitful Threesome: The Relationship between Yeasts, Insects, and Angiosperms. J Fungi (Basel) 2022; 8:984. [PMID: 36294549 PMCID: PMC9605484 DOI: 10.3390/jof8100984] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 09/13/2022] [Accepted: 09/18/2022] [Indexed: 07/30/2023] Open
Abstract
The importance of insects for angiosperm pollination is widely recognized. In fact, approximately 90% of all plant species benefit from animal-mediated pollination. However, only recently, a third part player in this story has been properly acknowledged. Microorganisms inhabiting floral nectar, among which yeasts have a prominent role, can ferment glucose, fructose, sucrose, and/or other carbon sources in this habitat. As a result of their metabolism, nectar yeasts produce diverse volatile organic compounds (VOCs) and other valuable metabolites. Notably, some VOCs of yeast origin can influence insects' foraging behavior, e.g., by attracting them to flowers (although repelling effects have also been reported). Moreover, when insects feed on nectar, they also ingest yeast cells, which provide them with nutrients and protect them from pathogenic microorganisms. In return, insects serve yeasts as transportation and a safer habitat during winter when floral nectar is absent. From the plant's point of view, the result is flowers being pollinated. From humanity's perspective, this ecological relationship may also be highly profitable. Therefore, prospecting nectar-inhabiting yeasts for VOC production is of major biotechnological interest. Substances such as acetaldehyde, ethyl acetate, ethyl butyrate, and isobutanol have been reported in yeast volatomes, and they account for a global market of approximately USD 15 billion. In this scenario, the present review addresses the ecological, environmental, and biotechnological outlooks of this three-party mutualism, aiming to encourage researchers worldwide to dig into this field.
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Affiliation(s)
- Eduardo D. Fenner
- Graduate Program in Environment and Sustainable Technologies, Federal University of Fronteira Sul, Campus Cerro Largo, Cerro Largo 97900-000, RS, Brazil
- Laboratory of Yeast Biochemistry, Federal University of Fronteira Sul, Campus Chapecó, Chapecó 89815-899, SC, Brazil
| | - Thamarys Scapini
- Laboratory of Microbiology and Bioprocesses, Federal University of Fronteira Sul, Campus Erechim, Erechim 99700-970, RS, Brazil
| | - Mariana da Costa Diniz
- Laboratory of Yeast Biochemistry, Federal University of Fronteira Sul, Campus Chapecó, Chapecó 89815-899, SC, Brazil
| | - Anderson Giehl
- Laboratory of Yeast Biochemistry, Federal University of Fronteira Sul, Campus Chapecó, Chapecó 89815-899, SC, Brazil
| | - Helen Treichel
- Laboratory of Microbiology and Bioprocesses, Federal University of Fronteira Sul, Campus Erechim, Erechim 99700-970, RS, Brazil
| | - Sergio Álvarez-Pérez
- Department of Animal Health, Faculty of Veterinary Medicine, Complutense University of Madrid, 28040 Madrid, Spain
| | - Sérgio L. Alves
- Graduate Program in Environment and Sustainable Technologies, Federal University of Fronteira Sul, Campus Cerro Largo, Cerro Largo 97900-000, RS, Brazil
- Laboratory of Yeast Biochemistry, Federal University of Fronteira Sul, Campus Chapecó, Chapecó 89815-899, SC, Brazil
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15
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Burgess EC, Schaeffer RN. The Floral Microbiome and Its Management in Agroecosystems: A Perspective. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:9819-9825. [PMID: 35917340 DOI: 10.1021/acs.jafc.2c02037] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Disease management is critical to ensuring healthy crop yields and is often targeted at flowers because of their susceptibility to pathogens and direct link to reproduction. Many disease management strategies are unsustainable however because of the potential for pathogens to evolve resistance, or nontarget effects on beneficial insects. Manipulating the floral microbiome holds some promise as a sustainable alternative to chemical means of disease control. In this perspective, we discuss the current state of research concerning floral microbiome assembly and management in agroecosystems as well as future directions aimed at improving the sustainability of disease control and insect-mediated ecosystem services.
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Affiliation(s)
- Emily C Burgess
- Department of Biology, Utah State University, Logan, Utah 84322, United States
| | - Robert N Schaeffer
- Department of Biology, Utah State University, Logan, Utah 84322, United States
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16
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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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17
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Jiménez Elvira N, Ushio M, Sakai S. Are microbes growing on flowers evil? Effects of old flower microbes on fruit set in a wild ginger with one-day flowers, Alpinia japonica (Zingiberaceae). METABARCODING AND METAGENOMICS 2022. [DOI: 10.3897/mbmg.6.84331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Flowers are colonized and inhabited by diverse microbes. Flowers have various mechanisms to suppress microbial growth, such as flower volatiles, reactive oxygen and secondary compounds. Besides, plants rapidly replace flowers that have a short lifespan, and old flowers senesce. They may contribute to avoiding adverse effects of the microbes. In this study, we investigate if the flower microbial community on old flowers impedes fruit and seed production in a wild ginger with one-day flowers. We focus on microbes on old flowers because they may be composed of microbes that would grow during flowering if the flowers did not have mechanisms to suppress microbial growth. We inoculated newly opened flowers with old flower microbes, and monitored the effects on fruit and seed set. We also assessed prokaryotic communities on the flowers using 16S rRNA amplicon sequencing. We found six bacterial amplicon sequence variants (ASVs) whose proportions were increased on the inoculated flowers. These ASVs were also found on flower buds and flowers that were bagged by net or paper during anthesis, suggesting that they had been present in small numbers prior to flowering. Fruit set was negatively associated with the proportions of these ASVs, while seed set was not. The results suggest that old flowers harbor microbial communities different from those at anthesis, and that the microbes abundant on old flowers negatively affect plant reproduction. Although it has received little attention, antagonistic microbes that rapidly proliferate on the flowers may have affected the evolution of various flower characteristics such as flower volatiles and life span.
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18
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Martin VN, Schaeffer RN, Fukami T. Potential effects of nectar microbes on pollinator health. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210155. [PMID: 35491594 DOI: 10.1098/rstb.2021.0155] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Floral nectar is prone to colonization by nectar-adapted yeasts and bacteria via air-, rain-, and animal-mediated dispersal. Upon colonization, microbes can modify nectar chemical constituents that are plant-provisioned or impart their own through secretion of metabolic by-products or antibiotics into the nectar environment. Such modifications can have consequences for pollinator perception of nectar quality, as microbial metabolism can leave a distinct imprint on olfactory and gustatory cues that inform foraging decisions. Furthermore, direct interactions between pollinators and nectar microbes, as well as consumption of modified nectar, have the potential to affect pollinator health both positively and negatively. Here, we discuss and integrate recent findings from research on plant-microbe-pollinator interactions and their consequences for pollinator health. We then explore future avenues of research that could shed light on the myriad ways in which nectar microbes can affect pollinator health, including the taxonomic diversity of vertebrate and invertebrate pollinators that rely on this reward. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.
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Affiliation(s)
| | | | - Tadashi Fukami
- Department of Biology, Stanford University, Stanford, CA, USA
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19
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Crowley-Gall A, Trouillas FP, Niño EL, Schaeffer RN, Nouri MT, Crespo M, Vannette RL. Floral Microbes Suppress Growth of Monilinia laxa with Minimal Effects on Honey Bee Feeding. PLANT DISEASE 2022; 106:432-438. [PMID: 34455807 DOI: 10.1094/pdis-03-21-0549-re] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Management of Monilinia laxa, the causal agent of brown rot blossom blight in almond (Prunus dulcis), relies heavily on the use of chemical fungicides during bloom. However, chemical fungicides can have nontarget effects on beneficial arthropods, including pollinators, and select for resistance in the pathogen of concern. Almond yield is heavily reliant on successful pollination by healthy honey bees (Apis mellifera); thus, identifying sustainable, effective, and pollinator-friendly control methods for blossom blight during bloom is desirable. Flower-inhabiting microbes could provide a natural, sustainable form of biocontrol for M. laxa, while potentially minimizing costly nontarget effects on almond pollinators and the services they provide. As pollinators are sensitive to floral microbes and their associated taste and scent cues, assessing effects of prospective biocontrol species on pollinator attraction is also necessary. Here, our objective was to isolate and identify potential biocontrol microbes from an array of agricultural and natural flowering hosts and test their efficacy in suppressing M. laxa growth in culture. Out of an initial 287 bacterial and fungal isolates identified, 56 were screened using a dual culture plate assay. Most strains reduced M. laxa growth in vitro. Ten particularly effective candidate microbes were further screened for their effect on honey bee feeding. Of the 10, nine were found to both strongly suppress M. laxa growth in culture and not reduce honey bee feeding. These promising results suggest a number of strong candidates for augmentative microbial biocontrol of brown rot blossom blight in almond with potentially minimal effects on honey bee pollination.
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Affiliation(s)
- Amber Crowley-Gall
- Department of Entomology and Nematology, University California-Davis, Davis, CA 95616
| | - Florent P Trouillas
- Department of Plant Pathology, University California-Davis and Kearney Agriculture Research and Extension Center, Davis, CA 95616
| | - Elina L Niño
- Department of Entomology and Nematology, University California-Davis, Davis, CA 95616
| | | | - Mohamed T Nouri
- University of California Cooperative Extension San Joaquin County, Stockton, CA 95206
| | - Maria Crespo
- Department of Plant Pathology, University California-Davis and Kearney Agriculture Research and Extension Center, Davis, CA 95616
| | - Rachel L Vannette
- Department of Entomology and Nematology, University California-Davis, Davis, CA 95616
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20
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Nicoletti R, Becchimanzi A. Ecological and Molecular Interactions between Insects and Fungi. Microorganisms 2022; 10:microorganisms10010096. [PMID: 35056545 PMCID: PMC8779020 DOI: 10.3390/microorganisms10010096] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 12/24/2021] [Accepted: 01/01/2022] [Indexed: 02/04/2023] Open
Abstract
Insects and fungi represent two of the most widespread groupings of organisms in nature, occurring in every kind of ecological context and impacting agriculture and other human activities in various ways. Moreover, they can be observed to reciprocally interact, establishing a wide range of symbiotic relationships, from mutualism to antagonism. The outcome of these relationships can in turn affect the extent at which species of both organisms can exert their noxious effects, as well as the management practices which are to be adopted to counter them. In conjunction with the launch of a Special Issue of Microorganisms with the same title, this article offers a general overview of the manifold aspects related to such interactions from the perspective of implementing our capacity to regulate them in a direction more favorable for the environment, crop production and human health.
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Affiliation(s)
- Rosario Nicoletti
- Council for Agricultural Research and Economics, Research Centre for Olive, Fruit and Citrus Crops, 81100 Caserta, Italy
- Department of Agricultural Sciences, University of Naples Federico II, 80055 Portici, Italy;
- Correspondence:
| | - Andrea Becchimanzi
- Department of Agricultural Sciences, University of Naples Federico II, 80055 Portici, Italy;
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21
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Tiwari S, Jadhav R, Avchar R, Lanjekar V, Datar M, Baghela A. Nectar Yeast Community of Tropical Flowering Plants and Assessment of Their Osmotolerance and Xylitol-Producing Potential. Curr Microbiol 2021; 79:28. [PMID: 34905093 DOI: 10.1007/s00284-021-02700-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 11/03/2021] [Indexed: 11/29/2022]
Abstract
Floral nectar is colonised by microbes, especially yeasts which alter the scent, temperature, and chemical composition of nectar, thereby playing an essential role in pollination. The yeast communities inhabiting the nectar of tropical flowers of India are not well explored. We isolated 48 yeast strains from seven different tropical flowering plants. Post MSP-PCR-based screening, 23 yeast isolates and two yeast-like fungi were identified, which belonged to 16 species of 12 genera viz. Candida (2 species), Aureobasidium (2 species), Metschnikowia (2 species), Meyerozyma (1 species), Saitozyma (1 species), Wickerhamomyces (1 species), Kodamaea (2 species), Pseudozyma (1 species), Starmerella (1 species), Hanseniaspora (1 species), Rhodosporidiobolus (1 species), Moesziomyces (1 species), and two putative novel species. All yeast strains were assessed for their osmotolerance abilities in high salt and sugar concentration. Among all the isolates, C. nivariensis (SRA2.2, SRA1.1 and SRA2.1), M. caribbica (SRA4.8 and SRA4.6), S. flava SRA4.2, and M. reukaufii SRA3.2 showed significant growth in high concentrations of sugar (40-50% glucose), as well as salt (12-15% NaCl). All 25 strains were also screened for their ability to utilise xylose to produce xylitol. Meyerozyma caribbica was the most efficient xylitol producer, wherein three strains of this species (SRA4.6, SRA4.1, and SRA4.8) generated 18.61 to 21.56 g l-1 of xylitol, with 0.465-0.539 g g-1 yields. Through this study, we draw attention towards the tropical floral nectar as a potential niche for the isolation of diverse, osmotolerant, and xylitol-producing yeasts. Such osmotolerant yeasts have potential applications in food industries and biofuel production.
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Affiliation(s)
- Snigdha Tiwari
- National Fungal Culture Collection of India (NFCCI), Biodiversity and Palaeobiology Group, MACS-Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India.,Savitribai Phule Pune University, Ganeshkhind, Pune, 411007, India
| | - Reshma Jadhav
- National Fungal Culture Collection of India (NFCCI), Biodiversity and Palaeobiology Group, MACS-Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India
| | - Rameshwar Avchar
- National Fungal Culture Collection of India (NFCCI), Biodiversity and Palaeobiology Group, MACS-Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India.,Savitribai Phule Pune University, Ganeshkhind, Pune, 411007, India
| | - Vikram Lanjekar
- Bioenergy Group, MACS-Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India
| | - Mandar Datar
- Biodiversity and Palaeobiology Group, Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India
| | - Abhishek Baghela
- National Fungal Culture Collection of India (NFCCI), Biodiversity and Palaeobiology Group, MACS-Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India. .,Savitribai Phule Pune University, Ganeshkhind, Pune, 411007, India.
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22
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Vannette RL, McMunn MS, Hall GW, Mueller TG, Munkres I, Perry D. Culturable bacteria are more common than fungi in floral nectar and are more easily dispersed by thrips, a ubiquitous flower visitor. FEMS Microbiol Ecol 2021; 97:6430164. [PMID: 34791198 DOI: 10.1093/femsec/fiab150] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 11/15/2021] [Indexed: 01/04/2023] Open
Abstract
Variation in dispersal ability among taxa affects community assembly and biodiversity maintenance within metacommunities. Although fungi and bacteria frequently coexist, their relative dispersal abilities are poorly understood. Nectar-inhabiting microbial communities affect plant reproduction and pollinator behavior, and are excellent models for studying dispersal of bacteria and fungi in a metacommunity framework. Here, we assay dispersal ability of common nectar bacteria and fungi in an insect-based dispersal experiment. We then compare these results with the incidence and abundance of culturable flower-inhabiting bacteria and fungi within naturally occurring flowers across two coflowering communities in California across two flowering seasons. Our microbial dispersal experiment demonstrates that bacteria disperse via thrips among artificial habitat patches more readily than fungi. In the field, incidence and abundance of culturable bacteria and fungi were positively correlated, but bacteria were much more widespread. These patterns suggest shared dispersal routes or habitat requirements among culturable bacteria and fungi, but differences in dispersal or colonization frequency by thrips, common flower visitors. The finding that culturable bacteria are more common among nectar sampled here, in part due to superior thrips-mediated dispersal, may have relevance for microbial life history, community assembly of microbes, and plant-pollinator interactions.
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Affiliation(s)
- Rachel L Vannette
- Department of Entomology and Nematology, University of California Davis, Davis, CA 95616, USA
| | - Marshall S McMunn
- Department of Entomology and Nematology, University of California Davis, Davis, CA 95616, USA
| | - Griffin W Hall
- Department of Entomology and Nematology, University of California Davis, Davis, CA 95616, USA
| | - Tobias G Mueller
- Department of Entomology and Nematology, University of California Davis, Davis, CA 95616, USA
| | - Ivan Munkres
- Department of Entomology and Nematology, University of California Davis, Davis, CA 95616, USA
| | - Douglas Perry
- Department of Entomology and Nematology, University of California Davis, Davis, CA 95616, USA
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23
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Avalos M, Garbeva P, Vader L, van Wezel GP, Dickschat JS, Ulanova D. Biosynthesis, evolution and ecology of microbial terpenoids. Nat Prod Rep 2021; 39:249-272. [PMID: 34612321 DOI: 10.1039/d1np00047k] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Covering: through June 2021Terpenoids are the largest class of natural products recognised to date. While mostly known to humans as bioactive plant metabolites and part of essential oils, structurally diverse terpenoids are increasingly reported to be produced by microorganisms. For many of the compounds biological functions are yet unknown, but during the past years significant insights have been obtained for the role of terpenoids in microbial chemical ecology. Their functions include stress alleviation, maintenance of cell membrane integrity, photoprotection, attraction or repulsion of organisms, host growth promotion and defense. In this review we discuss the current knowledge of the biosynthesis and evolution of microbial terpenoids, and their ecological and biological roles in aquatic and terrestrial environments. Perspectives on their biotechnological applications, knowledge gaps and questions for future studies are discussed.
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Affiliation(s)
- Mariana Avalos
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands. .,Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB Wageningen, The Netherlands
| | - Paolina Garbeva
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB Wageningen, The Netherlands
| | - Lisa Vader
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands.
| | - Gilles P van Wezel
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands. .,Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB Wageningen, The Netherlands
| | - Jeroen S Dickschat
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB Wageningen, The Netherlands.,University of Bonn, Kekulé-Institute of Organic Chemistry and Biochemistry, Gerhard-Domagk-Straße 1, 53121 Bonn, Germany
| | - Dana Ulanova
- Faculty of Agriculture and Marine Science, Kochi University, 200 Otsu, Monobe, Nankoku, Kochi 783-8502, Japan.
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24
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Đurović G, Van Neerbos FAC, Bossaert S, Herrera-Malaver B, Steensels J, Arnó J, Wäckers F, Sobhy IS, Verstrepen KJ, Jacquemyn H, Lievens B. The Pupal Parasitoid Trichopria drosophilae Is Attracted to the Same Yeast Volatiles as Its Adult Host. J Chem Ecol 2021; 47:788-798. [PMID: 34269959 DOI: 10.1007/s10886-021-01295-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/20/2021] [Accepted: 06/22/2021] [Indexed: 10/20/2022]
Abstract
There is increasing evidence that microorganisms, particularly fungi and bacteria, emit volatile compounds that mediate the foraging behaviour of insects and therefore have the potential to affect key ecological relationships. However, to what extent microbial volatiles affect the olfactory response of insects across different trophic levels remains unclear. Adult parasitoids use a variety of chemical stimuli to locate potential hosts, including those emitted by the host's habitat, the host itself, and microorganisms associated with the host. Given the great capacity of parasitoids to utilize and learn odours to increase foraging success, parasitoids of eggs, larvae, or pupae may respond to the same volatiles the adult stage of their hosts use when locating their resources, but compelling evidence is still scarce. In this study, using Saccharomyces cerevisiae we show that Trichopria drosophilae, a pupal parasitoid of Drosophila species, is attracted to the same yeast volatiles as their hosts in the adult stage, i.e. acetate esters. Parasitoids significantly preferred the odour of S. cerevisiae over the blank medium in a Y-tube olfactometer. Deletion of the yeast ATF1 gene, encoding a key acetate ester synthase, decreased attraction of T. drosophilae, while the addition of synthetic acetate esters to the fermentation medium restored parasitoid attraction. Bioassays with individual compounds revealed that the esters alone were not as attractive as the volatile blend of S. cerevisiae, suggesting that other volatile compounds also contribute to the attraction of T. drosophilae. Altogether, our results indicate that pupal parasitoids respond to the same volatiles as the adult stage of their hosts, which may aid them in locating oviposition sites.
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Affiliation(s)
- Gordana Đurović
- CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department M2S, KU Leuven, B-3001, Leuven, Belgium.,Leuven Plant Institute (LPI), KU Leuven, B-3001, Leuven, Belgium.,Research and Innovation Centre, Fondazione Edmund Mach, 38098, San Michele all'Adige, Italy.,Biobest, B-2260, Westerlo, Belgium
| | - Francine A C Van Neerbos
- CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department M2S, KU Leuven, B-3001, Leuven, Belgium.,Leuven Plant Institute (LPI), KU Leuven, B-3001, Leuven, Belgium
| | - Sofie Bossaert
- CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department M2S, KU Leuven, B-3001, Leuven, Belgium.,Leuven Plant Institute (LPI), KU Leuven, B-3001, Leuven, Belgium
| | - Beatriz Herrera-Malaver
- CMPG Laboratory of Genetics and Genomics, Department M2S, KU Leuven, B-3001, Leuven, Belgium.,Flanders Institute for Biotechnology (VIB), KU Leuven Center for Microbiology, B-3001, Leuven, Belgium
| | - Jan Steensels
- CMPG Laboratory of Genetics and Genomics, Department M2S, KU Leuven, B-3001, Leuven, Belgium.,Flanders Institute for Biotechnology (VIB), KU Leuven Center for Microbiology, B-3001, Leuven, Belgium
| | | | - Felix Wäckers
- Biobest, B-2260, Westerlo, Belgium.,Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK
| | - Islam S Sobhy
- CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department M2S, KU Leuven, B-3001, Leuven, Belgium.,Leuven Plant Institute (LPI), KU Leuven, B-3001, Leuven, Belgium.,Department of Plant Protection, Faculty of Agriculture, Suez Canal University, Ismailia, Egypt
| | - Kevin J Verstrepen
- CMPG Laboratory of Genetics and Genomics, Department M2S, KU Leuven, B-3001, Leuven, Belgium.,Flanders Institute for Biotechnology (VIB), KU Leuven Center for Microbiology, B-3001, Leuven, Belgium
| | - Hans Jacquemyn
- Leuven Plant Institute (LPI), KU Leuven, B-3001, Leuven, Belgium.,Laboratory of Plant Conservation and Population Biology, Biology Department, KU Leuven, B-3001, Leuven, Belgium
| | - Bart Lievens
- CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department M2S, KU Leuven, B-3001, Leuven, Belgium. .,Leuven Plant Institute (LPI), KU Leuven, B-3001, Leuven, Belgium.
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25
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Colda A, Bossaert S, Verreth C, Vanhoutte B, Honnay O, Keulemans W, Lievens B. Inoculation of pear flowers with Metschnikowia reukaufii and Acinetobacter nectaris enhances attraction of honeybees and hoverflies, but does not increase fruit and seed set. PLoS One 2021; 16:e0250203. [PMID: 33886638 PMCID: PMC8061982 DOI: 10.1371/journal.pone.0250203] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 04/02/2021] [Indexed: 11/28/2022] Open
Abstract
Currently, one of the most important challenges is to provide sufficient and affordable food and energy for a fast-growing world population, alongside preserving natural habitats and maintaining biodiversity. About 35% of the global food production depends on animals for pollination. In recent years, an alarming worldwide decline in pollinators has been reported, putting our food production under additional pressure. Therefore, there is an urgent need to find sustainable ways to ensure this crucial ecosystem service. Recent studies have shown that floral nectar is generally colonized by microorganisms, specifically yeasts and bacteria, which may alter nectar chemistry and enhance attraction of pollinators. In this study, we investigated changes in pollinator foraging behavior and pollination success in European pear (Pyrus communis L.) cultivars 'Regal Red' and 'Sweet Sensation' (red sports of 'Doyenné de Comice') after flower inoculation with the typical nectar-inhabiting microorganisms Metschnikowia reukaufii and Acinetobacter nectaris, and a combination of both. Pollination success was monitored by measuring the number of flower visits, fruit set and seed set in two consecutive years, 2019 and 2020. Results revealed that application of a mixture of M. reukaufii and A. nectaris resulted in significantly higher visitation rates of honeybees and hoverflies. By contrast, no effects on flower visits were found when yeasts and bacteria were applied separately. Fruit set and seed set were not significantly affected by any of the inoculation treatments. The only factors affecting fruit set were initial number of flower clusters on the trees and the year. The absence of treatment effects can most likely be attributed to the fact that pollination was not a limiting factor for fruit set in our experiments. Altogether, our results show that inoculation of flowers with nectar microbes can modify pollinator foraging patterns, but did not lead to increased pollination success under the conditions tested.
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Affiliation(s)
- Agneta Colda
- Division of Crop Biotechnics, Laboratory for Fruit Breeding and Biotechnology, Department of Biosystems, KU Leuven, Leuven, Belgium
| | - Sofie Bossaert
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, Center of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Christel Verreth
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, Center of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Bart Vanhoutte
- Research Center for Fruit Growing, Sint-Truiden, Belgium
| | - Olivier Honnay
- Division of Ecology, Evolution and Biodiversity Conservation, Department of Biology, Plant Conservation and Population Biology, KU Leuven, Leuven, Belgium
| | - Wannes Keulemans
- Division of Crop Biotechnics, Laboratory for Fruit Breeding and Biotechnology, Department of Biosystems, KU Leuven, Leuven, Belgium
| | - Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, Center of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
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26
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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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Cullen NP, Fetters AM, Ashman TL. Integrating microbes into pollination. CURRENT OPINION IN INSECT SCIENCE 2021; 44:48-54. [PMID: 33248285 DOI: 10.1016/j.cois.2020.11.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/02/2020] [Accepted: 11/06/2020] [Indexed: 06/12/2023]
Abstract
Microbes (fungi, bacteria and viruses) living within flowers are hypothesized to affect pollination. We evaluate current support for this idea at each stage of the pollination process. Evidence to date is convincing that microbes influence pollinator attraction, but data are heavily weighted toward bumblebees and the effects of nectar yeasts. Effects of microbes on the efficacy of pollinator visits is understudied and variable outcomes from field studies suggest quality of pollinator visits, not only quantity, are likely involved. The effect of microbes on pollen performance is underappreciated. Beyond the effect of pathogenic viruses, the impacts of pollen-transmitted endophytic microbes on pollen viability or tube growth are unknown but could affect the outcome of pollen receipt. Future research integrating microbes into pollination should broaden taxonomic diversity of microbes, pollinators and plants and the processes under study.
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Affiliation(s)
- Nevin P Cullen
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Andrea M Fetters
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Tia-Lynn Ashman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
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Evolutionary and Ecological Considerations on Nectar-Mediated Tripartite Interactions in Angiosperms and Their Relevance in the Mediterranean Basin. PLANTS 2021; 10:plants10030507. [PMID: 33803275 PMCID: PMC7999006 DOI: 10.3390/plants10030507] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 02/22/2021] [Accepted: 03/03/2021] [Indexed: 11/16/2022]
Abstract
The Mediterranean basin hosts a high diversity of plants and bees, and it is considered one of the world's biodiversity hotspots. Insect pollination, i.e., pollen transfer from male reproductive structures to conspecific female ones, was classically thought to be a mutualistic relationship that links these two groups of organisms, giving rise to an admirable and complex network of interactions. Although nectar is often involved in mediating these interactions, relatively little is known about modifications in its chemical traits during the evolution of plants. Here, we examine how the current sucrose-dominated floral nectar of most Mediterranean plants could have arisen in the course of evolution of angiosperms. The transition from hexose-rich to sucrose-rich nectar secretion was probably triggered by increasing temperature and aridity during the Cretaceous period, when most angiosperms were radiating. This transition may have opened new ecological niches for new groups of insects that were co-diversifying with angiosperms and for specific nectar-dwelling yeasts that originated later (i.e., Metschnikowiaceae). Our hypothesis embeds recent discoveries in nectar biology, such as the involvement of nectar microbiota and nectar secondary metabolites in shaping interactions with pollinators, and it suggests a complex, multifaceted ecological and evolutionary scenario that we are just beginning to discover.
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29
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Álvarez-Pérez S, Dhami MK, Pozo MI, Crauwels S, Verstrepen KJ, Herrera CM, Lievens B, Jacquemyn H. Genetic admixture increases phenotypic diversity in the nectar yeast Metschnikowia reukaufii. FUNGAL ECOL 2021. [DOI: 10.1016/j.funeco.2020.101016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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30
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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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31
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Vannette RL. The Floral Microbiome: Plant, Pollinator, and Microbial Perspectives. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2020. [DOI: 10.1146/annurev-ecolsys-011720-013401] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Flowers at times host abundant and specialized communities of bacteria and fungi that influence floral phenotypes and interactions with pollinators. Ecological processes drive variation in microbial abundance and composition at multiple scales, including among plant species, among flower tissues, and among flowers on the same plant. Variation in microbial effects on floral phenotype suggests that microbial metabolites could cue the presence or quality of rewards for pollinators, but most plants are unlikely to rely on microbes for pollinator attraction or reproduction. From a microbial perspective, flowers offer opportunities to disperse between habitats, but microbial species differ in requirements for and benefits received from such dispersal. The extent to which floral microbes shape the evolution of floral traits, influence fitness of floral visitors, and respond to anthropogenic change is unclear. A deeper understanding of these phenomena could illuminate the ecological and evolutionary importance of floral microbiomes and their role in the conservation of plant–pollinator interactions.
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Affiliation(s)
- Rachel L. Vannette
- Department of Entomology and Nematology, University of California, Davis, California 95616, USA
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32
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From Diverse Origins to Specific Targets: Role of Microorganisms in Indirect Pest Biological Control. INSECTS 2020; 11:insects11080533. [PMID: 32823898 PMCID: PMC7469166 DOI: 10.3390/insects11080533] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/12/2020] [Accepted: 08/13/2020] [Indexed: 01/29/2023]
Abstract
Integrated pest management (IPM) is today a widely accepted pest management strategy to select and use the most efficient control tactics and at the same time reduce over-dependence on chemical insecticides and their potentially negative environmental effects. One of the main pillars of IPM is biological control. While biological control programs of pest insects commonly rely on natural enemies such as predatory insects, parasitoids and microbial pathogens, there is increasing evidence that plant, soil and insect microbiomes can also be exploited to enhance plant defense against herbivores. In this mini-review, we illustrate how microorganisms from diverse origins can contribute to plant fitness, functional traits and indirect defense responses against pest insects, and therefore be indirectly used to improve biological pest control practices. Microorganisms in the rhizosphere, phyllosphere and endosphere have not only been shown to enhance plant growth and plant strength, but also promote plant defense against herbivores both above- and belowground by providing feeding deterrence or antibiosis. Also, herbivore associated molecular patterns may be induced by microorganisms that come from oral phytophagous insect secretions and elicit plant-specific responses to herbivore attacks. Furthermore, microorganisms that inhabit floral nectar and insect honeydew produce volatile organic compounds that attract beneficial insects like natural enemies, thereby providing indirect pest control. Given the multiple benefits of microorganisms to plants, we argue that future IPMs should consider and exploit the whole range of possibilities that microorganisms offer to enhance plant defense and increase attraction, fecundity and performance of natural enemies.
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Goelen T, Sobhy IS, Vanderaa C, Wäckers F, Rediers H, Wenseleers T, Jacquemyn H, Lievens B. Bacterial phylogeny predicts volatile organic compound composition and olfactory response of an aphid parasitoid. OIKOS 2020. [DOI: 10.1111/oik.07301] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tim Goelen
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Dept of Microbial and Molecular Systems, KU Leuven BE‐3001 Leuven Belgium
| | - Islam S. Sobhy
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Dept of Microbial and Molecular Systems, KU Leuven BE‐3001 Leuven Belgium
- Dept of Plant Protection, Faculty of Agriculture, Suez Canal Univ. Ismailia Egypt
| | - Christophe Vanderaa
- Laboratory of Socio‐Ecology & Social Evolution, Biology Dept, KU Leuven Leuven Belgium
| | - Felix Wäckers
- Biobest, Westerlo, Belgium, and: Lancaster Environment Centre, Lancaster Univ. Lancaster UK
| | - Hans Rediers
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Dept of Microbial and Molecular Systems, KU Leuven BE‐3001 Leuven Belgium
| | - Tom Wenseleers
- Laboratory of Socio‐Ecology & Social Evolution, Biology Dept, KU Leuven Leuven Belgium
| | - Hans Jacquemyn
- Laboratory of Plant Conservation and Population Biology, Biology Dept, KU Leuven Leuven Belgium
| | - Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Dept of Microbial and Molecular Systems, KU Leuven BE‐3001 Leuven Belgium
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Goelen T, Sobhy IS, Vanderaa C, Boer JG, Delvigne F, Francis F, Wäckers F, Rediers H, Verstrepen KJ, Wenseleers T, Jacquemyn H, Lievens B. Volatiles of bacteria associated with parasitoid habitats elicit distinct olfactory responses in an aphid parasitoid and its hyperparasitoid. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13503] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tim Goelen
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM) Department of Microbial and Molecular Systems KU Leuven Leuven Belgium
| | - Islam S. Sobhy
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM) Department of Microbial and Molecular Systems KU Leuven Leuven Belgium
- Department of Plant Protection Faculty of Agriculture Suez Canal University Ismailia Egypt
| | - Christophe Vanderaa
- Laboratory of Socio‐Ecology & Social Evolution Biology Department KU Leuven Leuven Belgium
| | - Jetske G. Boer
- Department of Terrestrial Ecology Netherlands Institute of Ecology (NIOO‐KNAW) Wageningen The Netherlands
| | - Frank Delvigne
- Microbial Processes and Interactions (MiPI) TERRA Université de Liège‐Gembloux Agro‐Bio Tech Gembloux Belgium
| | - Frédéric Francis
- Functional & Evolutionary Entomology TERRA Université de Liège‐Gembloux Agro‐Bio Tech Gembloux Belgium
| | - Felix Wäckers
- Biobest Westerlo Belgium
- Lancaster Environment Centre Lancaster University Lancaster UK
| | - Hans Rediers
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM) Department of Microbial and Molecular Systems KU Leuven Leuven Belgium
| | - Kevin J. Verstrepen
- Lab for Systems Biology VIB Center for Microbiology & Centre of Microbial and Plant Genetics (CMPG) Lab for Genetics and Genomics Department of Microbial and Molecular Systems KU Leuven Leuven Belgium
| | - Tom Wenseleers
- Laboratory of Socio‐Ecology & Social Evolution Biology Department KU Leuven 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) Department of Microbial and Molecular Systems KU Leuven Leuven Belgium
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Klaps J, Lievens B, Álvarez-Pérez S. Towards a better understanding of the role of nectar-inhabiting yeasts in plant-animal interactions. Fungal Biol Biotechnol 2020; 7:1. [PMID: 31921433 PMCID: PMC6947986 DOI: 10.1186/s40694-019-0091-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 12/26/2019] [Indexed: 11/29/2022] Open
Abstract
Flowers offer a wide variety of substrates suitable for fungal growth. However, the mycological study of flowers has only recently begun to be systematically addressed from an ecological point of view. Most research on the topic carried out during the last decade has focused on studying the prevalence and diversity of flower-inhabiting yeasts, describing new species retrieved from floral parts and animal pollinators, and the use of select nectar yeasts as model systems to test ecological hypotheses. In this primer article, we summarize the current state of the art in floral nectar mycology and provide an overview of some research areas that, in our view, still require further attention, such as the influence of fungal volatile organic compounds on the foraging behavior of pollinators and other floral visitors, the analysis of the direct and indirect effects of nectar-inhabiting fungi on the fitness of plants and animals, and the nature and consequences of fungal-bacterial interactions taking place within flowers.
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Affiliation(s)
- Joon Klaps
- Department of Microbial and Molecular Systems (M2S), Laboratory for Process Microbial Ecology and Bioinspirational Management (PME & BIM), KU Leuven, Willem De Croylaan 46, Leuven, 3001 Belgium
| | - Bart Lievens
- Department of Microbial and Molecular Systems (M2S), Laboratory for Process Microbial Ecology and Bioinspirational Management (PME & BIM), KU Leuven, Willem De Croylaan 46, Leuven, 3001 Belgium
| | - Sergio Álvarez-Pérez
- Department of Microbial and Molecular Systems (M2S), Laboratory for Process Microbial Ecology and Bioinspirational Management (PME & BIM), KU Leuven, Willem De Croylaan 46, Leuven, 3001 Belgium
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36
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Mbaluto CM, Ayelo PM, Duffy AG, Erdei AL, Tallon AK, Xia S, Caballero-Vidal G, Spitaler U, Szelényi MO, Duarte GA, Walker WB, Becher PG. Insect chemical ecology: chemically mediated interactions and novel applications in agriculture. ARTHROPOD-PLANT INTERACTIONS 2020; 14:671-684. [PMID: 33193908 PMCID: PMC7650581 DOI: 10.1007/s11829-020-09791-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 10/16/2020] [Indexed: 05/19/2023]
Abstract
Insect chemical ecology (ICE) evolved as a discipline concerned with plant-insect interactions, and also with a strong focus on intraspecific pheromone-mediated communication. Progress in this field has rendered a more complete picture of how insects exploit chemical information in their surroundings in order to survive and navigate their world successfully. Simultaneously, this progress has prompted new research questions about the evolution of insect chemosensation and related ecological adaptations, molecular mechanisms that mediate commonly observed behaviors, and the consequences of chemically mediated interactions in different ecosystems. Themed meetings, workshops, and summer schools are ideal platforms for discussing scientific advancements as well as identifying gaps and challenges within the discipline. From the 11th to the 22nd of June 2018, the 11th annual PhD course in ICE was held at the Swedish University of Agricultural Sciences (SLU) Alnarp, Sweden. The course was made up of 35 student participants from 22 nationalities (Fig. 1a) as well as 32 lecturers. Lectures and laboratory demonstrations were supported by literature seminars, and four broad research areas were covered: (1) multitrophic interactions and plant defenses, (2) chemical communication focusing on odor sensing, processing, and behavior, (3) disease vectors, and (4) applied aspects of basic ICE research in agriculture. This particular article contains a summary and brief synthesis of these main emergent themes and discussions from the ICE 2018 course. In addition, we also provide suggestions on teaching the next generation of ICE scientists, especially during unprecedented global situations.
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Affiliation(s)
- Crispus M. Mbaluto
- Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Pusch straße 4, 04103 Leipzig, Germany
- Institute of Biodiversity, Friedrich-Schiller-Universität Jena, Dornburger Str. 159, 07743 Jena, Germany
| | - Pascal M. Ayelo
- International Centre of Insect Physiology and Ecology (Icipe), P.O. Box 30772-00100, Nairobi, Kenya
- Department of Zoology and Entomology, University of Pretoria, Hatfield, Private Bag X20, Pretoria, 0028 South Africa
| | - Alexandra G. Duffy
- Evolutionary Ecology Laboratories, Department of Biology, Brigham Young University, 4102 Life Science Building, Provo, UT 84602 USA
| | - Anna L. Erdei
- Zoology Department, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó str. 15, Budapest, 1022 Hungary
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 102, 23053 Alnarp, Sweden
| | - Anaїs K. Tallon
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 102, 23053 Alnarp, Sweden
| | - Siyang Xia
- Department of Ecology and Evolutionary Biology, Yale University, 21 Sachem Street, New Haven, CT 06511 USA
| | - Gabriela Caballero-Vidal
- INRAE, Institute of Ecology and Environmental Sciences of Paris, CNRS, IRD, UPEC, Sorbonne Université, Université Paris Diderot, Route de Saint-Cyr, 78026 Versailles Cedex, France
| | - Urban Spitaler
- Institute of Plant Health, Laimburg Research Centre, Laimburg 6, 3904 Ora, South Tyrol Italy
- Department of Crop Sciences, Institute of Plant Protection, University of Natural Resources and Life Sciences (BOKU), Gregor-Mendel-Straße 33, 1180 Vienna, Austria
| | - Magdolna O. Szelényi
- Zoology Department, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó str. 15, Budapest, 1022 Hungary
| | - Gonçalo A. Duarte
- LEAF-Linking Landscape, Environment, Agriculture and Food Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisbon, Portugal
| | - William B. Walker
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 102, 23053 Alnarp, Sweden
| | - Paul G. Becher
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 102, 23053 Alnarp, Sweden
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Pozo MI, Kemenade G, Oystaeyen A, Aledón‐Catalá T, Benavente A, Van den Ende W, Wäckers F, Jacquemyn H. The impact of yeast presence in nectar on bumble bee behavior and fitness. ECOL MONOGR 2019. [DOI: 10.1002/ecm.1393] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- María I. Pozo
- KU Leuven Biology Department Plant Population and Conservation Biology B‐3001 Heverlee Belgium
- Biobest Group, Research and Development B‐2260 Westerlo Belgium
| | - Gaby Kemenade
- KU Leuven Biology Department Plant Population and Conservation Biology B‐3001 Heverlee Belgium
- Biobest Group, Research and Development B‐2260 Westerlo Belgium
| | | | - Tomás Aledón‐Catalá
- KU Leuven Biology Department Plant Population and Conservation Biology B‐3001 Heverlee Belgium
- Biobest Group, Research and Development B‐2260 Westerlo Belgium
| | | | - Wim Van den Ende
- KU Leuven Biology Department Molecular Plant Biology B‐3001 Heverlee Belgium
| | - Felix Wäckers
- Biobest Group, Research and Development B‐2260 Westerlo Belgium
| | - Hans Jacquemyn
- KU Leuven Biology Department Plant Population and Conservation Biology B‐3001 Heverlee Belgium
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Yeast Volatomes Differentially Affect Larval Feeding in an Insect Herbivore. Appl Environ Microbiol 2019; 85:AEM.01761-19. [PMID: 31444202 PMCID: PMC6803314 DOI: 10.1128/aem.01761-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 08/18/2019] [Indexed: 01/25/2023] Open
Abstract
Yeasts interface insect herbivores with their food plants. Communication depends on volatile metabolites, and decoding this chemical dialogue is key to understanding the ecology of insect-yeast interactions. This study explores the volatomes of eight yeast species which have been isolated from foliage, from flowers or fruit, and from plant-feeding insects. These yeasts each release a rich bouquet of volatile metabolites, including a suite of known insect attractants from plant and floral scent. This overlap underlines the phylogenetic dimension of insect-yeast associations, which according to the fossil record long predate the appearance of flowering plants. Volatome composition is characteristic for each species, aligns with yeast taxonomy, and is further reflected by a differential behavioral response of cotton leafworm larvae, which naturally feed on foliage of a wide spectrum of broad-leaved plants. Larval discrimination may establish and maintain associations with yeasts and is also a substrate for designing sustainable insect management techniques. Yeasts form mutualistic interactions with insects. Hallmarks of this interaction include provision of essential nutrients, while insects facilitate yeast dispersal and growth on plant substrates. A phylogenetically ancient chemical dialogue coordinates this interaction, where the vocabulary, the volatile chemicals that mediate the insect response, remains largely unknown. Here, we used gas chromatography-mass spectrometry, followed by hierarchical cluster and orthogonal partial least-squares discriminant analyses, to profile the volatomes of six Metschnikowia spp., Cryptococcus nemorosus, and brewer’s yeast (Saccharomyces cerevisiae). The yeasts, which are all found in association with insects feeding on foliage or fruit, emit characteristic, species-specific volatile blends that reflect the phylogenetic context. Species specificity of these volatome profiles aligned with differential feeding of cotton leafworm (Spodoptera littoralis) larvae on these yeasts. Bioactivity correlates with yeast ecology; phylloplane species elicited a stronger response than fruit yeasts, and larval discrimination may provide a mechanism for establishment of insect-yeast associations. The yeast volatomes contained a suite of insect attractants known from plant and especially floral headspace, including (Z)-hexenyl acetate, ethyl (2E,4Z)-deca-2,4-dienoate (pear ester), (3E)-4,8-dimethylnona-1,3,7-triene (DMNT), linalool, α-terpineol, β-myrcene, or (E,E)-α-farnesene. A wide overlap of yeast and plant volatiles, notably floral scents, further emphasizes the prominent role of yeasts in plant-microbe-insect relationships, including pollination. The knowledge of insect-yeast interactions can be readily brought to practical application, as live yeasts or yeast metabolites mediating insect attraction provide an ample toolbox for the development of sustainable insect management. IMPORTANCE Yeasts interface insect herbivores with their food plants. Communication depends on volatile metabolites, and decoding this chemical dialogue is key to understanding the ecology of insect-yeast interactions. This study explores the volatomes of eight yeast species which have been isolated from foliage, from flowers or fruit, and from plant-feeding insects. These yeasts each release a rich bouquet of volatile metabolites, including a suite of known insect attractants from plant and floral scent. This overlap underlines the phylogenetic dimension of insect-yeast associations, which according to the fossil record long predate the appearance of flowering plants. Volatome composition is characteristic for each species, aligns with yeast taxonomy, and is further reflected by a differential behavioral response of cotton leafworm larvae, which naturally feed on foliage of a wide spectrum of broad-leaved plants. Larval discrimination may establish and maintain associations with yeasts and is also a substrate for designing sustainable insect management techniques.
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Smessaert J, Van Geel M, Verreth C, Crauwels S, Honnay O, Keulemans W, Lievens B. Temporal and spatial variation in bacterial communities of "Jonagold" apple (Malus x domestica Borkh.) and "Conference" pear (Pyrus communis L.) floral nectar. Microbiologyopen 2019; 8:e918. [PMID: 31441243 PMCID: PMC6925153 DOI: 10.1002/mbo3.918] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 07/07/2019] [Accepted: 07/14/2019] [Indexed: 12/24/2022] Open
Abstract
Production of many agricultural crops and fruits strongly depends on pollinators. For instance, pome fruits such as apple and pear are highly dependent on pollination for fruit set, fruit quality, and yield. Nectar is often inhabited by microbes, most often yeasts and bacteria, which may change nectar quality and therefore also affect plant–pollinator interactions. Here, we used high‐throughput 16S ribosomal RNA gene amplicon sequencing to investigate the temporal and spatial variation in bacterial communities in floral nectar of apple and pear. We sampled 15 apple (Malus x domestica Borkh.) and 15 pear (Pyrus communis L.) orchards distributed over the eastern part of Belgium over a timespan of seven days. Nectar bacterial community composition differed strongly among fruit species. Nectar of pear was dominated by Actinobacteria, followed by Proteobacteria and Firmicutes. Apple nectar was strongly enriched in Bacteroidetes, a phylum which until now has been found to be rarely associated with floral nectar. Nectar was dominated by only a few bacterial species, with Brevibacterium (Actinobacteria) and Undibacterium (Proteobacteria) as the most abundant bacteria in pear and apple nectar, respectively. Bacterial richness and diversity were found to fluctuate during flowering, likely due to changing environmental conditions. Additionally, spatial structure in nectar bacterial community composition was found in apple orchards, while this was not the case for pear. Differences in nectar bacterial communities between apple and pear nectar may differently affect the chemical and nutritional composition of the nectar, influencing pollinator attraction and visitation, and thus pollination efficacy in general.
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Affiliation(s)
- Jolien Smessaert
- Laboratory for Fruit Breeding and Biotechnology, Department of Biosystems, KU Leuven, Leuven, Belgium
| | - Maarten Van Geel
- Plant Conservation and Population Biology, Biology Department, KU Leuven, Leuven, Belgium
| | - Christel Verreth
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, KU Leuven, Sint-Katelijne-Waver, Belgium
| | - Sam Crauwels
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, KU Leuven, Sint-Katelijne-Waver, Belgium
| | - Olivier Honnay
- Plant Conservation and Population Biology, Biology Department, KU Leuven, Leuven, Belgium
| | - Wannes Keulemans
- Laboratory for Fruit Breeding and Biotechnology, Department of Biosystems, KU Leuven, Leuven, Belgium
| | - Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, KU Leuven, Sint-Katelijne-Waver, Belgium
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Rusman Q, Lucas-Barbosa D, Poelman EH, Dicke M. Ecology of Plastic Flowers. TRENDS IN PLANT SCIENCE 2019; 24:725-740. [PMID: 31204246 DOI: 10.1016/j.tplants.2019.04.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 04/16/2019] [Accepted: 04/25/2019] [Indexed: 05/20/2023]
Abstract
Plant phenotypic plasticity in response to herbivore attack includes changes in flower traits. Such herbivore-induced changes in flower traits have consequences for interactions with flower visitors. We synthesize here current knowledge on the specificity of herbivore-induced changes in flower traits, the underlying molecular mechanisms, and the ecological consequences for flower-associated communities. Herbivore-induced changes in flower traits seem to be largely herbivore species-specific. The extensive plasticity observed in flowers influences a highly connected web of interactions within the flower-associated community. We argue that the adaptive value of herbivore-induced plant responses and flower plasticity can be fully understood only from a community perspective rather than from pairwise interactions.
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Affiliation(s)
- Quint Rusman
- Laboratory of Entomology, Wageningen University, PO Box 16, 6700 AA Wageningen, The Netherlands.
| | - Dani Lucas-Barbosa
- Laboratory of Entomology, Wageningen University, PO Box 16, 6700 AA Wageningen, The Netherlands
| | - Erik H Poelman
- Laboratory of Entomology, Wageningen University, PO Box 16, 6700 AA Wageningen, The Netherlands
| | - Marcel Dicke
- Laboratory of Entomology, Wageningen University, PO Box 16, 6700 AA Wageningen, The Netherlands
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Yang M, Deng GC, Gong YB, Huang SQ. Nectar yeasts enhance the interaction between Clematis akebioides and its bumblebee pollinator. PLANT BIOLOGY (STUTTGART, GERMANY) 2019; 21:732-737. [PMID: 30636362 DOI: 10.1111/plb.12957] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 01/07/2019] [Indexed: 06/09/2023]
Abstract
It has been hypothesised that intense metabolism of nectar-inhabiting yeasts (NIY) may change nectar chemistry, including volatile profile, which may affect pollinator foraging behaviours and consequently plant fitness. However, empirical evidence for the plant-microbe-pollinator interactions remains little known. To test this hypothesis, we use a bumblebee-pollinated vine Clematis akebioides endemic to southwest China as an experimental model plant. To quantify the incidence and density of Metschnikowia reukaufii, a cosmopolitan NIY in floral nectar, a combination of yeast cultivation and microscopic cell-counting method was used. To examine the effects of NIY on plant-pollinator interactions, we used real flowers filled with artificial nectar with or without yeast cells. Then the volatile metabolites produced in the yeast-inoculated nectar were analysed with coupled gas chromatography and mass spectrometry (GC-MS). On average 79.3% of the C. akebioides flowers harboured M. reukaufii, and cell density of NIY was high to 7.4 × 104 cells mm-3 . In the field population, the presence of NIY in flowers of C. akebioides increased bumblebee (Bombus friseanus) pollinator visitation rate and consequently seed set per flower. A variety of fatty acid derivatives produced by M. reukaufii may be responsible for the above beneficial interactions. The volatiles produced by the metabolism of M. reukaufii may serve as an honest signal to attract bumblebee pollinators and indirectly promote the female reproductive fitness of C. akebioides, forming a potentially tripartite plant-microbe-pollinator mutualism.
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Affiliation(s)
- M Yang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - G-C Deng
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Y-B Gong
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - S-Q Huang
- Institute of Evolution and Ecology, School of Life Sciences, Central China Normal University, Wuhan, China
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Álvarez-Pérez S, Lievens B, Fukami T. Yeast-Bacterium Interactions: The Next Frontier in Nectar Research. TRENDS IN PLANT SCIENCE 2019; 24:393-401. [PMID: 30792076 DOI: 10.1016/j.tplants.2019.01.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 01/19/2019] [Accepted: 01/25/2019] [Indexed: 05/28/2023]
Abstract
Beyond its role as a reward for pollinators, floral nectar also provides a habitat for specialized and opportunistic yeasts and bacteria. These microbes modify nectar chemistry, often altering mutualistic relationships between plants and pollinators in ways that we are only beginning to understand. Many studies on this multi-partite system have focused on either yeasts or bacteria without consideration of yeast-bacterium interactions, but recent evidence suggests that such interactions drive the assembly of nectar microbial communities and its consequences for pollination. Unexplored potential mechanisms of yeast-bacterium interactions include the formation of physical complexes, nutritional interactions, antibiosis, signaling-based interactions, and horizontal gene transfer. We argue that studying these mechanisms can elucidate how nectar microbial communities are established and affect plant fitness via pollinators.
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Affiliation(s)
- Sergio Álvarez-Pérez
- KU Leuven, Department of Microbial and Molecular Systems (M2S), Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Campus De Nayer, B-2860 Sint-Katelijne-Waver, Belgium; Department of Biology, Stanford University, Stanford, CA 94305, USA.
| | - Bart Lievens
- KU Leuven, Department of Microbial and Molecular Systems (M2S), Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Campus De Nayer, B-2860 Sint-Katelijne-Waver, Belgium
| | - Tadashi Fukami
- Department of Biology, Stanford University, Stanford, CA 94305, USA. https://twitter.com/@TadashiFukami
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Attraction of the Green Lacewing Chrysoperla comanche (Neuroptera: Chrysopidae) to Yeast. J Chem Ecol 2019; 45:388-391. [PMID: 30828777 DOI: 10.1007/s10886-019-01060-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 02/13/2019] [Accepted: 02/21/2019] [Indexed: 10/27/2022]
Abstract
Many adult Chrysoperla comanche (Stephens) green lacewings were caught in traps baited with live yeast cultures during tests designed to catch olive fruit flies. All 13 yeast species tested were more attractive than the industry-standard dried torula yeast (Cyberlindnera jadinii; syn. Candida utilis). Live C. jadinii culture attracted significantly more lacewings than the inactive dried-pellet form of the same yeast species, demonstrating that volatiles from live yeast cultures attract adults of this lacewing. Odor profiles for two of the highly active yeasts tested herein (Lachancea thermotolerans and Solicoccozyma terrea) were similar to that for Metschnikowia pulcherrima, a yeast species isolated earlier from the gut diverticulum of Chrysoperla rufilabris. A new Metschnikowia species (M. chrysoperlae), along with two new Candida spp. that were recently realigned to one of the Metschnikowia clades (M. picachoensis and M. pimensis), were also identified from the diverticulum of C. comanche. Thus, one clade of Metschnikowia yeasts that commonly occur in floral nectar appears to exhibit mutualistic symbioses with Chrysoperla green lacewings. Both male and female C. comanche adults were attracted in the present study, and we speculate that males have exploited this symbiosis by offering Metschnikowia-laden regurgitant, including attractive volatiles, to females ('mating trophallaxis') as a nuptial gift.
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