1
|
Ravigné V, Rodrigues LR, Charlery de la Masselière M, Facon B, Kuczyński L, Radwan J, Skoracka A, Magalhães S. Understanding the joint evolution of dispersal and host specialisation using phytophagous arthropods as a model group. Biol Rev Camb Philos Soc 2024; 99:219-237. [PMID: 37724465 DOI: 10.1111/brv.13018] [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: 05/25/2023] [Revised: 09/11/2023] [Accepted: 09/11/2023] [Indexed: 09/20/2023]
Abstract
Theory generally predicts that host specialisation and dispersal should evolve jointly. Indeed, many models predict that specialists should be poor dispersers to avoid landing on unsuitable hosts while generalists will have high dispersal abilities. Phytophagous arthropods are an excellent group to test this prediction, given extensive variation in their host range and dispersal abilities. Here, we explore the degree to which the empirical literature on this group is in accordance with theoretical predictions. We first briefly outline the theoretical reasons to expect such a correlation. We then report empirical studies that measured both dispersal and the degree of specialisation in phytophagous arthropods. We find a correlation between dispersal and levels of specialisation in some studies, but with wide variation in this result. We then review theoretical attributes of species and environment that may blur this correlation, namely environmental grain, temporal heterogeneity, habitat selection, genetic architecture, and coevolution between plants and herbivores. We argue that theoretical models fail to account for important aspects, such as phenotypic plasticity and the impact of selective forces stemming from other biotic interactions, on both dispersal and specialisation. Next, we review empirical caveats in the study of this interplay. We find that studies use different measures of both dispersal and specialisation, hampering comparisons. Moreover, several studies do not provide independent measures of these two traits. Finally, variation in these traits may occur at scales that are not being considered. We conclude that this correlation is likely not to be expected from large-scale comparative analyses as it is highly context dependent and should not be considered in isolation from the factors that modulate it, such as environmental scale and heterogeneity, intrinsic traits or biotic interactions. A stronger crosstalk between theoretical and empirical studies is needed to understand better the prevalence and basis of the correlation between dispersal and specialisation.
Collapse
Affiliation(s)
- Virginie Ravigné
- CIRAD, UMR PHIM, - PHIM, University of Montpellier, CIRAD, INRAE, Institut Agro, IRD, TA A-120/K, Campus international de Baillarguet, avenue du Campus d'Agropolis, Montpellier Cedex 5, 34398, France
| | - Leonor R Rodrigues
- cE3c: Centre for Ecology, Evolution and Environmental Changes & CHANGE - Global Change and Sustainability Institute, Departamento Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, edifício C2, Lisboa, 1749-016, Portugal
| | - Maud Charlery de la Masselière
- cE3c: Centre for Ecology, Evolution and Environmental Changes & CHANGE - Global Change and Sustainability Institute, Departamento Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, edifício C2, Lisboa, 1749-016, Portugal
| | - Benoît Facon
- CBGP, INRAE, IRD, CIRAD, Institut Agro, University of Montpellier, 755 avenue du Campus Agropolis, CS 34988, Montferrier sur Lez cedex, 30016, France
| | - Lechosław Kuczyński
- Population Ecology Lab, Faculty of Biology, Institute of Environmental Biology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 6, Poznań, 61-614, Poland
| | - Jacek Radwan
- Evolutionary Biology Group, Faculty of Biology, Institute of Environmental Biology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 6, Poznań, 61-614, Poland
| | - Anna Skoracka
- Population Ecology Lab, Faculty of Biology, Institute of Environmental Biology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 6, Poznań, 61-614, Poland
| | - Sara Magalhães
- cE3c: Centre for Ecology, Evolution and Environmental Changes & CHANGE - Global Change and Sustainability Institute, Departamento Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, edifício C2, Lisboa, 1749-016, Portugal
| |
Collapse
|
2
|
Seifert CL, Strutzenberger P, Fiedler K. Ecological specialisation and range size determine intraspecific body size variation in a speciose clade of insect herbivores. OIKOS 2022. [DOI: 10.1111/oik.09338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Carlo L. Seifert
- Dept of Nature Forest Conservation, Georg‐August‐Univ. of Göttingen Göttingen Germany
| | | | - Konrad Fiedler
- Dept of Botany and Biodiversity Research, Univ. of Vienna Vienna Austria
| |
Collapse
|
3
|
Bisch-Knaden S, Rafter MA, Knaden M, Hansson BS. Unique neural coding of crucial versus irrelevant plant odors in a hawkmoth. eLife 2022; 11:77429. [PMID: 35622402 PMCID: PMC9142141 DOI: 10.7554/elife.77429] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 05/09/2022] [Indexed: 12/29/2022] Open
Abstract
The sense of smell is pivotal for nocturnal moths to locate feeding and oviposition sites. However, these crucial resources are often rare and their bouquets are intermingled with volatiles emanating from surrounding ‘background’ plants. Here, we asked if the olfactory system of female hawkmoths, Manduca sexta, could differentiate between crucial and background cues. To answer this question, we collected nocturnal headspaces of numerous plants in a natural habitat of M. sexta. We analyzed the chemical composition of these headspaces and used them as stimuli in physiological experiments at the antenna and in the brain. The intense odors of floral nectar sources evoked strong responses in virgin and mated female moths, most likely enabling the localization of profitable flowers at a distance. Bouquets of larval host plants and most background plants, in contrast, were subtle, thus potentially complicating host identification. However, despite being subtle, antennal responses and brain activation patterns evoked by the smell of larval host plants were clearly different from those evoked by other plants. Interestingly, this difference was even more pronounced in the antennal lobe of mated females, revealing a status-dependent tuning of their olfactory system towards oviposition sites. Our study suggests that female moths possess unique neural coding strategies to find not only conspicuous floral cues but also inconspicuous bouquets of larval host plants within a complex olfactory landscape.
Collapse
Affiliation(s)
- Sonja Bisch-Knaden
- Max-Planck-Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Jena, Germany
| | | | - Markus Knaden
- Max-Planck-Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Jena, Germany
| | - Bill S Hansson
- Max-Planck-Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Jena, Germany
| |
Collapse
|
4
|
Samková A, Raška J, Hadrava J, Skuhrovec J. Effect of host switching simulation on the fitness of the gregarious parasitoid Anaphes flavipes from a novel two-generation approach. Sci Rep 2021; 11:19473. [PMID: 34593852 PMCID: PMC8484349 DOI: 10.1038/s41598-021-98393-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 08/30/2021] [Indexed: 11/13/2022] Open
Abstract
Herbivorous insects can escape the strong pressure of parasitoids by switching to feeding on new host plants. Parasitoids can adapt to this change but at the cost of changing their preferences and performance. For gregarious parasitoids, fitness changes are not always observable in the F1 generation but only in the F2 generation. Here, with the model species and gregarious parasitoid Anaphes flavipes, we examined fitness changes in the F1 generation under pressure from the simulation of host switching, and by a new two-generation approach, we determined the impact of these changes on fitness in the F2 generation. We showed that the parasitoid preference for host plants depends on hatched or oviposited learning in relation to the possibility of parasitoid decisions between different host plants. Interestingly, we showed that after simulation of parasitoids following host switching, in the new environment of a fictitious host plant, parasitoids reduced the fictitious host. At the same time, parasitoids also reduced fertility because in fictitious hosts, they are not able to complete larval development. However, from a two-generation approach, the distribution of parasitoid offspring into both native and fictitious hosts caused lower parasitoid clutch size in native hosts and higher individual offspring fertility in the F2 generation.
Collapse
Affiliation(s)
- Alena Samková
- Department of Plant Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 00, Prague 6-Suchdol, Czech Republic.
| | - Jan Raška
- Department of Plant Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 00, Prague 6-Suchdol, Czech Republic
| | - Jiří Hadrava
- Department of Zoology, Faculty of Science, Charles University, Viničná 7, 128 43, Prague 2, Czech Republic.,Institute of Entomology, Biological Centre, Czech Academy of Sciences, Branišovská 31, 370 05, České Budějovice, Czech Republic
| | - Jiří Skuhrovec
- Crop Research Institute, Drnovská 507, 161 06, Praha 6-Ruzyně, Czech Republic
| |
Collapse
|
5
|
Elliott CH, Gillett CPDT, Parsons E, Rubinoff D. Conservation conundrum: Endangered species persists on noxious weed. Biotropica 2021. [DOI: 10.1111/btp.13003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Christine H. Elliott
- Department of Plant and Environmental Protection Sciences University of Hawaiʻi at Mānoa Honolulu HI USA
| | - Conrad P. D. T. Gillett
- Department of Plant and Environmental Protection Sciences University of Hawaiʻi at Mānoa Honolulu HI USA
| | | | - Daniel Rubinoff
- Department of Plant and Environmental Protection Sciences University of Hawaiʻi at Mānoa Honolulu HI USA
| |
Collapse
|
6
|
Johnson CA, Smith GP, Yule K, Davidowitz G, Bronstein JL, Ferrière R. Coevolutionary transitions from antagonism to mutualism explained by the Co-Opted Antagonist Hypothesis. Nat Commun 2021; 12:2867. [PMID: 34001894 PMCID: PMC8129128 DOI: 10.1038/s41467-021-23177-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 04/07/2021] [Indexed: 11/13/2022] Open
Abstract
There is now good evidence that many mutualisms evolved from antagonism; why or how, however, remains unclear. We advance the Co-Opted Antagonist (COA) Hypothesis as a general mechanism explaining evolutionary transitions from antagonism to mutualism. COA involves an eco-coevolutionary process whereby natural selection favors co-option of an antagonist to perform a beneficial function and the interacting species coevolve a suite of phenotypic traits that drive the interaction from antagonism to mutualism. To evaluate the COA hypothesis, we present a generalized eco-coevolutionary framework of evolutionary transitions from antagonism to mutualism and develop a data-based, fully ecologically-parameterized model of a small community in which a lepidopteran insect pollinates some of its larval host plant species. More generally, our theory helps to reconcile several major challenges concerning the mechanisms of mutualism evolution, such as how mutualisms evolve without extremely tight host fidelity (vertical transmission) and how ecological context influences evolutionary outcomes, and vice-versa. While there is strong evidence that many mutualisms evolved from antagonism, how or why remains unclear. A study combining theory and a data-based model sheds light on how mutualisms evolve without extremely tight host fidelity and how ecological context affects evolutionary outcomes and vice-versa.
Collapse
Affiliation(s)
- Christopher A Johnson
- Dept. of Ecology and Evolutionary Biology, University of Arizona, P.O. Box 210088, Tucson, AZ, USA. .,Institute of Integrative Biology, ETH Zürich, Universitäetstrasse 16, Zürich, Switzerland. .,Dept. of Ecology and Evolutionary Biology, Princeton University, 106a Guyot Hall, Princeton, NJ, USA.
| | - Gordon P Smith
- Dept. of Ecology and Evolutionary Biology, University of Arizona, P.O. Box 210088, Tucson, AZ, USA.,Dept. of Neurobiology and Behavior, Cornell University, 215 Tower Road, Ithaca, NY, USA
| | - Kelsey Yule
- Dept. of Ecology and Evolutionary Biology, University of Arizona, P.O. Box 210088, Tucson, AZ, USA.,Biodiversity Knowledge Integration Center, Arizona State University, 734W Alameda Drive, Tempe, AZ, USA
| | - Goggy Davidowitz
- Dept. of Entomology, University of Arizona, 1140 E. South Campus Dr., Tucson, AZ, USA
| | - Judith L Bronstein
- Dept. of Ecology and Evolutionary Biology, University of Arizona, P.O. Box 210088, Tucson, AZ, USA
| | - Régis Ferrière
- Dept. of Ecology and Evolutionary Biology, University of Arizona, P.O. Box 210088, Tucson, AZ, USA.,Institut de Biologie de l'ENS (IBENS), École Normale Supérieure CNRS UMR 8197, 46 rue d'Ulm, Paris, France.,iGLOBES International Research Laboratory, École Normale Supérieure, Université Paris Sciences & Lettres CNRS UMI 3157, University of Arizona, 845N Park Avenue, Tucson, AZ, USA
| |
Collapse
|
7
|
Kingsolver JG, Moore ME, Augustine KE, Hill CA. Responses of Manduca sexta larvae to heat waves. J Exp Biol 2021; 224:238099. [PMID: 34424973 DOI: 10.1242/jeb.236505] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 02/16/2021] [Indexed: 01/01/2023]
Abstract
Climate change is increasing the frequency of heat waves and other extreme weather events experienced by organisms. How does the number and developmental timing of heat waves affect survival, growth and development of insects? Do heat waves early in development alter performance later in development? We addressed these questions using experimental heat waves with larvae of the tobacco hornworm, Manduca sexta. The experiments used diurnally fluctuating temperature treatments differing in the number (0-3) and developmental timing (early, middle and/or late in larval development) of heat waves, in which a single heat wave involved three consecutive days with a daily maximum temperature of 42°C. Survival to pupation declined with increasing number of heat waves. Multiple (but not single) heat waves significantly reduced development time and pupal mass; the best models for the data indicated that both the number and developmental timing of heat waves affected performance. In addition, heat waves earlier in development significantly reduced growth and development rates later in larval development. Our results illustrate how the frequency and developmental timing of sublethal heat waves can have important consequences for life history traits in insects.
Collapse
Affiliation(s)
- Joel G Kingsolver
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - M Elizabeth Moore
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Kate E Augustine
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Christina A Hill
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| |
Collapse
|
8
|
Paudel S, Lin PA, Hoover K, Felton GW, Rajotte EG. Asymmetric Responses to Climate Change: Temperature Differentially Alters Herbivore Salivary Elicitor and Host Plant Responses to Herbivory. J Chem Ecol 2020; 46:891-905. [PMID: 32700062 PMCID: PMC7467972 DOI: 10.1007/s10886-020-01201-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 06/07/2020] [Accepted: 07/20/2020] [Indexed: 12/31/2022]
Abstract
The effect of temperature on insect-plant interactions in the face of changing climate is complex as the plant, its herbivores and their interactions are usually affected differentially leading to an asymmetry in response. Using experimental warming and a combination of biochemical and herbivory bioassays, the effects of elevated temperatures and herbivore damage (Helicoverpa zea) on resistance and tolerance traits of Solanum lycopersicum var. Better boy (tomato), as well as herbivory performance and salivary defense elicitors were examined. Insects and plants were differentially sensitive towards warming within the experimental temperature range. Herbivore growth rate increased with temperature, whereas plants growth as well as the ability to tolerate stress measured by photosynthesis recovery and regrowth ability were compromised at the highest temperature regime. In particular, temperature influenced the caterpillars’ capacity to induce plant defenses due to changes in the amount of a salivary defense elicitor, glucose oxidase (GOX). This was further complexed by the temperature effects on plant inducibility, which was significantly enhanced at an above-optimum temperature; this paralleled with an increased plants resistance to herbivory but significantly varied between previously damaged and undamaged leaves. Elevated temperatures produced asymmetry in species’ responses and changes in the relationship among species, indicating a more complicated response under a climate change scenario.
Collapse
Affiliation(s)
- Sulav Paudel
- Department of Entomology, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Po-An Lin
- Department of Entomology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Kelli Hoover
- Department of Entomology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Gary W Felton
- Department of Entomology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Edwin G Rajotte
- Department of Entomology, The Pennsylvania State University, University Park, PA, 16802, USA
| |
Collapse
|
9
|
Wilson JK, Ruiz L, Duarte J, Davidowitz G. The nutritional landscape of host plants for a specialist insect herbivore. Ecol Evol 2019; 9:13104-13113. [PMID: 31871632 PMCID: PMC6912913 DOI: 10.1002/ece3.5730] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 09/15/2019] [Indexed: 01/03/2023] Open
Abstract
Nutrition has far-reaching effects on both the ecology and evolution of species. A substantial body of work has examined the role of host plant quality on insect herbivores, with a particular focus on specialist-generalist dynamics, the interaction of growth and other physiological attributes on fitness and tritrophic effects. Measures of plant quality usually involve one or two axes of nutritional space: typically secondary metabolites or elemental proxies (N and C) of protein and carbohydrates, respectively.Here, we describe the nutrient space of seven host plants of the specialist insect herbivore, Manduca sexta, using an approach that measures physiologically relevant sources of nutrition, soluble protein and digestible carbohydrates. We show that plant species differ markedly in their nutrient content, offering developing insect herbivores a range of available nutrient spaces that also depend on the age of the leaves being consumed.The majority of host-plant species produce diets that are suboptimal to the herbivore, likely resulting in varying levels of compensatory feeding for M. sexta to reach target levels of protein to ensure successful growth and development. Low-quality diets can also impact immune function leading to complex patterns of optimization of plant resources that maximizes both growth and the ability to defend from parasitoids and pathogens. This study is the first to quantify the nutrient space of a suite of host plants used by an insect herbivore using physiologically relevant measures of nutrition.
Collapse
Affiliation(s)
| | - Laura Ruiz
- Neuroscience and Cognitive ScienceUniversity of ArizonaTucsonAZUSA
| | - Jesse Duarte
- Ecology and Evolutionary BiologyUniversity of ArizonaTucsonAZUSA
| | | |
Collapse
|
10
|
Campbell SA, Vallano DM. Plant defences mediate interactions between herbivory and the direct foliar uptake of atmospheric reactive nitrogen. Nat Commun 2018; 9:4743. [PMID: 30413701 PMCID: PMC6226520 DOI: 10.1038/s41467-018-07134-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 03/23/2018] [Indexed: 11/09/2022] Open
Abstract
Reactive nitrogen from human sources (e.g., nitrogen dioxide, NO2) is taken up by plant roots following deposition to soils, but can also be assimilated by leaves directly from the atmosphere. Leaf uptake should alter plant metabolism and overall nitrogen balance and indirectly influence plant consumers; however, these consequences remain poorly understood. Here we show that direct foliar assimilation of NO2 increases levels of nitrogen-based defensive metabolites in leaves and reduces herbivore consumption and growth. These results suggest that atmospheric reactive nitrogen could have cascading negative effects on communities of herbivorous insects. We further show that herbivory induces a decrease in foliar uptake, indicating that consumers could limit the ability of vegetation to act as a sink for nitrogen pollutants (e.g., smog from mobile emissions). Our study suggests that the interactions of foliar uptake, plant defence and herbivory could have significant implications for understanding the environmental consequences of reactive nitrogen.
Collapse
Affiliation(s)
- Stuart A Campbell
- Department of Animal & Plant Sciences, P3 Centre for Translational Plant Science, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
- Department of Ecology & Evolutionary Biology, Cornell University, Ithaca, NY, 14853, USA.
| | - Dena M Vallano
- Department of Ecology & Evolutionary Biology, Cornell University, Ithaca, NY, 14853, USA
- Region 9 Air Division, U.S. Environmental Protection Agency, San Francisco, CA, 94105, USA
| |
Collapse
|
11
|
Vidal MC, Murphy SM. Quantitative measure of fitness in tri-trophic interactions and its influence on diet breadth of insect herbivores. Ecology 2018; 99:2681-2691. [PMID: 30289561 DOI: 10.1002/ecy.2527] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 09/03/2018] [Accepted: 09/18/2018] [Indexed: 11/12/2022]
Abstract
Herbivore-plant interactions should be studied using a tri-trophic approach, but we lack a quantitative measure of the combined effect of top-down and bottom-up forces on herbivore fitness. We propose the combination of the bi-trophic fitness slopes as a tri-trophic fitness measure. We use the relationship between fitness associated with top-down and bottom-up forces and the frequency of host plant use to calculate the top-down and bottom-up fitness slopes, which we then combine to obtain three possible directions of tri-trophic slopes. A positive tri-trophic slope indicates that herbivores have overall greater tri-trophic fitness on the more frequently used hosts. A null tri-trophic fitness slope indicates that herbivores have similar fitness on all host plants. A negative tri-trophic slope indicates that herbivores have generally lower fitness on the more frequently used hosts. We tested the explanation power of our method using data from the literature that tested herbivore host shifts and experimentally using a generalist herbivore with variable diet breadth across populations. We found that in host shifts, herbivores have higher tri-trophic fitness on the novel host, while in generalist populations, herbivores use most frequently the best host available. We present applications in other research areas and consider the limitations of our approach. Our approach is a first step towards a comprehensive model of multiple selective forces acting on the evolution of interactions.
Collapse
Affiliation(s)
- Mayra C Vidal
- Department of Biological Sciences, University of Denver, Boettcher West 302, 2050 E. Iliff Avenue Denver, Colorado, 80208, USA
| | - Shannon M Murphy
- Department of Biological Sciences, University of Denver, Boettcher West 302, 2050 E. Iliff Avenue Denver, Colorado, 80208, USA
| |
Collapse
|
12
|
Bernal JS, Medina RF. Agriculture sows pests: how crop domestication, host shifts, and agricultural intensification can create insect pests from herbivores. CURRENT OPINION IN INSECT SCIENCE 2018; 26:76-81. [PMID: 29764664 DOI: 10.1016/j.cois.2018.01.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 01/23/2018] [Accepted: 01/26/2018] [Indexed: 05/28/2023]
Abstract
We argue that agriculture as practiced creates pests. We use three examples (Corn leafhopper, Dalbulus maidis; Western corn rootworm, Diabrotica virgifera virgifera; Cotton fleahopper, Pseudatomoscelis seriatus) to illustrate: firstly, how since its origins, agriculture has proven conducive to transforming selected herbivores into pests, particularly through crop domestication and spread, and agricultural intensification, and; secondly, that the herbivores that became pests were among those hosted by crop wild relatives or associates, and were pre-adapted either as whole species or component subpopulations. Two of our examples, Corn leafhopper and Western corn rootworm, illustrate how following a host shift to a domesticated host, emergent pests 'hopped' onto crops and rode expansion waves to spread far beyond the geographic ranges of their wild hosts. Western corn rootworm exemplifies how an herbivore-tolerant crop was left vulnerable when it was bred for yield and protected with insecticides. Cotton fleahopper illustrates how removing preferred wild host plants from landscapes and replacing them with crops, allows herbivores with flexible host preferences to reach pest-level populations. We conclude by arguing that in the new geological epoch we face, the Anthropocene, we can improve agriculture by looking to our past to identify and avoid missteps of early and recent farmers.
Collapse
Affiliation(s)
- Julio S Bernal
- Department of Entomology, Texas A&M University, College Station, TX 77843-2475, United States.
| | - Raul F Medina
- Department of Entomology, Texas A&M University, College Station, TX 77843-2475, United States
| |
Collapse
|
13
|
McMillan LE, Miller DW, Adamo SA. Eating when ill is risky: immune defense impairs food detoxification in the caterpillar Manduca sexta. ACTA ACUST UNITED AC 2018; 221:jeb.173336. [PMID: 29217626 DOI: 10.1242/jeb.173336] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 11/30/2017] [Indexed: 11/20/2022]
Abstract
Mounting an immune response consumes resources, which should lead to increased feeding. However, activating the immune system reduces feeding (i.e. illness-induced anorexia) in both vertebrates and invertebrates, suggesting that it may be beneficial. We suggest that illness-induced anorexia may be an adaptive response to conflicts between immune defense and food detoxification. We found that activating an immune response in the caterpillar Manduca sexta increased its susceptibility to the toxin permethrin. Conversely, a sublethal dose of permethrin reduced resistance to the bacterium Serratia marcescens, demonstrating a negative interaction between detoxification and immune defense. Immune system activation and toxin challenge each depleted the amount of glutathione in the hemolymph. Increasing glutathione concentration in the hemolymph increased survival for both toxin- and immune+toxin-challenged groups. The results of this rescue experiment suggest that decreased glutathione availability, such as occurs during an immune response, impairs detoxification. We also found that the expression of some detoxification genes were not upregulated during a combined immune-toxin challenge, although they were when animals received a toxin challenge alone. These results suggest that immune defense reduces food detoxification capacity. Illness-induced anorexia may protect animals by decreasing exposure to food toxins when detoxification is impaired.
Collapse
Affiliation(s)
- Laura E McMillan
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, NS, Canada, B3H4R2
| | - Dylan W Miller
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, NS, Canada, B3H4R2
| | - Shelley A Adamo
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, NS, Canada, B3H4R2
| |
Collapse
|
14
|
Temperature effects on a marine herbivore depend strongly on diet across multiple generations. Oecologia 2018; 187:483-494. [DOI: 10.1007/s00442-018-4084-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 01/22/2018] [Indexed: 10/18/2022]
|
15
|
Davidowitz G, Roff D, Nijhout HF. Synergism and Antagonism of Proximate Mechanisms Enable and Constrain the Response to Simultaneous Selection on Body Size and Development Time: An Empirical Test Using Experimental Evolution. Am Nat 2016; 188:499-520. [PMID: 27788344 DOI: 10.1086/688653] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Natural selection acts on multiple traits simultaneously. How mechanisms underlying such traits enable or constrain their response to simultaneous selection is poorly understood. We show how antagonism and synergism among three traits at the developmental level enable or constrain evolutionary change in response to simultaneous selection on two focal traits at the phenotypic level. After 10 generations of 25% simultaneous directional selection on all four combinations of body size and development time in Manduca sexta (Sphingidae), the changes in the three developmental traits predict 93% of the response of development time and 100% of the response of body size. When the two focal traits were under synergistic selection, the response to simultaneous selection was enabled by juvenile hormone and ecdysteroids and constrained by growth rate. When the two focal traits were under antagonistic selection, the response to selection was due primarily to change in growth rate and constrained by the two hormonal traits. The approach used here reduces the complexity of the developmental and endocrine mechanisms to three proxy traits. This generates explicit predictions for the evolutionary response to selection that are based on biologically informed mechanisms. This approach has broad applicability to a diverse range of taxa, including algae, plants, amphibians, mammals, and insects.
Collapse
|
16
|
Clarke AR. Why so many polyphagous fruit flies (Diptera: Tephritidae)? A further contribution to the ‘generalism’ debate. Biol J Linn Soc Lond 2016. [DOI: 10.1111/bij.12880] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anthony R Clarke
- School of Earth, Environment and Biological Sciences; Queensland University of Technology (QUT); Brisbane Qld 4001 Australia
- Plant Biosecurity Cooperative Research Centre; LPO Box 5012 Bruce ACT 2617 Australia
| |
Collapse
|
17
|
Grosman AH, Molina-Rugama AJ, Mendes-Dias R, Sabelis MW, Menken SBJ, Pallini A, Breeuwer JAJ, Janssen A. No adaptation of a herbivore to a novel host but loss of adaptation to its native host. Sci Rep 2015; 5:16211. [PMID: 26577696 PMCID: PMC4649677 DOI: 10.1038/srep16211] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 10/05/2015] [Indexed: 11/25/2022] Open
Abstract
Most herbivorous arthropods are host specialists and the question is which mechanisms drive the evolution of such specialization. The theory of antagonistic pleiotropy suggests that there is a trade-off between adaptation of herbivores to a novel host and their native host. The mutation accumulation hypothesis proposes that herbivores on a novel host lose their adaptation to the native host through the accumulation of mutations with negligible effects on performance on the novel host. Experimental evidence for either of the two hypotheses is scarce. We compared the fitness of two sympatric moth strains from an introduced host and a native host. The strain from the novel host did not perform better on this host than the strain from the native host. The strain from the novel host performed less well on the native host than did the strain from the native host. Hence, selection on the novel host did not result in noticeable gain in performance, but adaptation to the native host was lost. These results are more readily explained by the mutation-accumulation hypothesis than by the trade-off hypothesis.
Collapse
Affiliation(s)
- Amir H Grosman
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | | | | | - Maurice W Sabelis
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Steph B J Menken
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Angelo Pallini
- Department of Entomology, Federal University of Viçosa, Minas Gerais, Brazil
| | - Johannes A J Breeuwer
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Arne Janssen
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| |
Collapse
|
18
|
Eck DJ, Shaw RG, Geyer CJ, Kingsolver JG. An integrated analysis of phenotypic selection on insect body size and development time. Evolution 2015; 69:2525-32. [DOI: 10.1111/evo.12744] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 07/18/2015] [Indexed: 12/01/2022]
Affiliation(s)
- Daniel J. Eck
- School of Statistics; University of Minnesota; 313 Ford Hall, 224 Church Street S.E. Minneapolis Minnesota 55455
| | - Ruth G. Shaw
- Department of Ecology, Evolution, and Behavior and Minnesota Center for Community Genetics; University of Minnesota; 100 Ecology Building, 1987 Upper Buford Circle St. Paul Minnesota 55108
| | - Charles J. Geyer
- School of Statistics; University of Minnesota; 313 Ford Hall, 224 Church Street S.E. Minneapolis Minnesota 55455
| | | |
Collapse
|
19
|
Chaianunporn T, Hovestadt T. Evolutionary responses to climate change in parasitic systems. GLOBAL CHANGE BIOLOGY 2015; 21:2905-2916. [PMID: 25857843 DOI: 10.1111/gcb.12944] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Accepted: 03/10/2015] [Indexed: 06/04/2023]
Abstract
Species may respond to climate change in many ecological and evolutionary ways. In this simulation study, we focus on the concurrent evolution of three traits in response to climate change, namely dispersal probability, temperature tolerance (or niche width), and temperature preference (optimal habitat). More specifically, we consider evolutionary responses in host species involved in different types of interaction, that is parasitism or commensalism, and for low or high costs of a temperature tolerance-fertility trade-off (cost of generalization). We find that host species potentially evolve all three traits simultaneously in response to increasing temperature but that the evolutionary response interacts and may be compensatory depending on the conditions. The evolutionary adjustment of temperature preference is slower in the parasitism than in commensalism scenario. Parasitism, in turn, selects for higher temperature tolerance and increased dispersal. High costs for temperature tolerance (i.e. generalization) restrict evolution of tolerance and thus lead to a faster response in temperature preference than that observed under low costs. These results emphasize the possible role of biotic interactions and the importance of 'multidimensional' evolutionary responses to climate change.
Collapse
Affiliation(s)
- Thotsapol Chaianunporn
- Biozentrum, Field Station Fabrikschleichach, University of Würzburg, Glashüttenstrasse 5, 96181, Rauhenebrach, Germany
| | - Thomas Hovestadt
- Biozentrum, Field Station Fabrikschleichach, University of Würzburg, Glashüttenstrasse 5, 96181, Rauhenebrach, Germany
- Department of Biology (TEREC), Ghent University, K.L. Ledeganckstraat 35, 9000, Gent, Belgium
| |
Collapse
|
20
|
Kingsolver JG, Higgins JK, Augustine KE. Fluctuating temperatures and ectotherm growth: distinguishing non-linear and time-dependent effects. J Exp Biol 2015; 218:2218-25. [DOI: 10.1242/jeb.120733] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 05/11/2015] [Indexed: 12/16/2022]
Abstract
Most terrestrial ectotherms experience diurnal and seasonal variation in temperature. Because thermal performance curves are non-linear, mean performance can differ in fluctuating and constant thermal environments. However, time-dependent effects—effects of the order and duration of exposure to temperature—can also influence mean performance. We quantified the non-linear and time-dependent effects of diurnally fluctuating temperatures for larval growth rates in the Tobacco Hornworm, Manduca sexta L., with four main results. First, the shape of the thermal performance curve for growth rate depended on the duration of exposure: e.g. optimal temperature and thermal breadth were greater for growth rates measured over short (24h during the last instar) compared with long (the entire period of larval growth) time periods. Second, larvae reared in diurnally fluctuating temperatures had significantly higher optimal temperatures and maximal growth rates than larvae reared in constant temperatures. Third, we quantified mean growth rates for larvae maintained at three mean temperatures (20°C, 25°C, 30°C) and three diurnal temperature ranges (+0°C, +5°C, +10°C). Diurnal fluctuations had opposite effects on mean growth rates at low vs high mean temperature. Fourth, we used short-term and long-term thermal performance curves to predict the non-linear effects of fluctuating temperatures for mean growth rates, and compared these to our experimental results. Both short- and long-term curves yielded poor predictions of mean growth rate at higher mean temperatures with fluctuations. Our results suggest caution in using constant temperature studies to model the consequences of variable thermal environments.
Collapse
Affiliation(s)
- Joel G. Kingsolver
- Department of Biology, University of North Carolina, Chapel Hill NC 27599, USA
| | - Jessica K. Higgins
- Department of Biology, University of North Carolina, Chapel Hill NC 27599, USA
| | - Kate E. Augustine
- Department of Biology, University of North Carolina, Chapel Hill NC 27599, USA
| |
Collapse
|
21
|
Bauerfeind SS, Fischer K. Targeting the right trait: The relative suitability of a host plant depends on the herbivore trait considered and ambient temperature. Basic Appl Ecol 2013. [DOI: 10.1016/j.baae.2013.08.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
22
|
Seiter S, Kingsolver J. Environmental determinants of population divergence in life-history traits for an invasive species: climate, seasonality and natural enemies. J Evol Biol 2013; 26:1634-45. [DOI: 10.1111/jeb.12159] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 01/16/2013] [Accepted: 01/23/2013] [Indexed: 12/01/2022]
Affiliation(s)
- S. Seiter
- Department of Ecology, Evolution and Organismal Biology; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - J. Kingsolver
- Department of Biology; University of North Carolina; Chapel Hill NC USA
| |
Collapse
|
23
|
Trauer U, Hilker M. Parental legacy in insects: variation of transgenerational immune priming during offspring development. PLoS One 2013; 8:e63392. [PMID: 23700423 PMCID: PMC3658988 DOI: 10.1371/journal.pone.0063392] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 04/03/2013] [Indexed: 02/06/2023] Open
Abstract
In insects, a parental immune challenge can prepare and enhance offspring immune activity. Previous studies of such transgenerational immune priming (TGIP) mainly focused on a single offspring life stage. However, different developmental stages may be exposed to different risks and show different susceptibility to parental immune priming. Here we addressed the question (i) whether TGIP effects on the immunity of Manduca sexta offspring vary among the different developmental offspring stages. We differentiated between unchallenged and immunochallenged offspring; for the latter type of offspring, we further investigated (ii) whether TGIP has an impact on the time that enhanced immune levels persist after offspring immune challenge. Finally, we determined (iii) whether TGIP effects on offspring performance depend on the offspring stage. Our results show that TGIP effects on phenoloxidase (PO) activity, but not on antibacterial activity, vary among unchallenged offspring stages. In contrast, TGIP effects on PO and antibacterial activity did not vary among immunochallenged offspring stages. The persistence of enhanced immune levels in immunochallenged offspring was dependent on the parental immune state. Antibacterial (but not PO) activity in offspring of immunochallenged parents decreased over five days after pupal immune challenge, whereas no significant change over time was detectable in offspring of control parents. Finally, TGIP effects on the developmental time of unchallenged offspring varied among stages; young larvae of immunochallenged parents developed faster and gained more weight than larvae of control parents. However, offspring females of immunochallenged parents laid fewer eggs than females derived from control parents. These findings suggest that the benefits which the offspring gains from TGIP during juvenile development are paid by the adults with reduced reproductive power. Our study shows that TGIP effects vary among offspring stages and depend on the type of immunity (PO or antibacterial activity) as well as the time past offspring immune challenge.
Collapse
Affiliation(s)
- Ute Trauer
- Institute of Biology – Applied Zoology/Animal Ecology, Freie Universität Berlin, Berlin, Germany
| | - Monika Hilker
- Institute of Biology – Applied Zoology/Animal Ecology, Freie Universität Berlin, Berlin, Germany
- * E-mail:
| |
Collapse
|
24
|
Chaianunporn T, Hovestadt T. Concurrent evolution of random dispersal and habitat niche width in host-parasitoid systems. Ecol Modell 2012. [DOI: 10.1016/j.ecolmodel.2012.09.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
25
|
Influences of Plant Traits on Immune Responses of Specialist and Generalist Herbivores. INSECTS 2012; 3:573-92. [PMID: 26466545 PMCID: PMC4553612 DOI: 10.3390/insects3020573] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 05/25/2012] [Accepted: 06/13/2012] [Indexed: 11/25/2022]
Abstract
Specialist and generalist insect herbivore species often differ in how they respond to host plant traits, particularly defensive traits, and these responses can include weakened or strengthened immune responses to pathogens and parasites. Accurate methods to measure immune response in the presence and absence of pathogens and parasites are necessary to determine whether susceptibility to these natural enemies is reduced or increased by host plant traits. Plant chemical traits are particularly important in that host plant metabolites may function as antioxidants beneficial to the immune response, or interfere with the immune response of both specialist and generalist herbivores. Specialist herbivores that are adapted to process and sometimes accumulate specific plant compounds may experience high metabolic demands that may decrease immune response, whereas the metabolic demands of generalist species differ due to more broad-substrate enzyme systems. However, the direct deleterious effects of plant compounds on generalist herbivores may weaken their immune responses. Further research in this area is important given that the ecological relevance of plant traits to herbivore immune responses is equally important in natural systems and agroecosystems, due to potential incompatibility of some host plant species and cultivars with biological control agents of herbivorous pests.
Collapse
|
26
|
Diamond SE, Kingsolver JG. Host plant adaptation and the evolution of thermal reaction norms. Oecologia 2012; 169:353-60. [PMID: 22127429 DOI: 10.1007/s00442-011-2206-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 11/08/2011] [Indexed: 10/15/2022]
Abstract
For most ectotherms, increasing the rearing temperature reduces the final (adult) body size, producing a negative slope for the thermal reaction norm. Recent studies show that this relationship may be reversed under conditions of low resource quality, producing a positive slope for the thermal reaction norm. If populations or species differ in the degree of evolutionary adaptation to a resource, how does this differential adaptation alter their thermal reaction norms? We used a common garden experiment with the tobacco hornworm, Manduca sexta, to address this question. We examined the thermal reaction norms for body size of two populations of M. sexta that differ in their evolutionary exposures to an atypical, low-quality resource (devil's claw; Proboscidea louisianica), but have comparable exposures to a typical, high-quality resource (tobacco; Nicotiana tabacum). Both populations had increased mean larval mortalities and development times when reared on devil's claw compared with tobacco, but the magnitudes of these increases differed between populations. Both populations had similar, negatively sloped thermal reaction norms on the typical, high-quality resource (tobacco), but had divergent, non-negative thermal reaction norms on the atypical, low-quality resource (devil's claw): the population with the longer evolutionary history of exposure to the atypical resource exhibited a flat (rather than positive) reaction norm. These results suggest that population differences in host plant adaptation can predictably influence the slopes of thermal reaction norms.
Collapse
Affiliation(s)
- Sarah E Diamond
- Department of Biology, North Carolina State University, Raleigh, NC 27695-7617, USA.
| | | |
Collapse
|
27
|
Kingsolver JG, Diamond SE, Seiter SA, Higgins JK. Direct and indirect phenotypic selection on developmental trajectories in Manduca sexta. Funct Ecol 2012. [DOI: 10.1111/j.1365-2435.2012.01972.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
28
|
Barman AK, Parajulee MN, Sansone CG, Medina RF. Host preference of cotton fleahopper, Pseudatomoscelis seriatus (Reuter) is not labile to geographic origin and prior experience. ENVIRONMENTAL ENTOMOLOGY 2012; 41:125-132. [PMID: 22525067 DOI: 10.1603/en11221] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Several phytophagous insects exhibit distinct preference for their host plants. In widely distributed generalist insects, host preference can be influenced by geographic variation in host plant distribution and abundance as well as by prior experience. We have studied host preference of the cotton fleahopper, Pseudatomoscelis seriatus (Reuter), a pest of cotton in Texas and other neighboring states, by measuring olfactory orientation to horsemint (Monarda punctata L.) and cotton (Gossypium hirsutum L.). Horsemint is one of the primary, native, wild hosts of cotton fleahopper during late-spring and early summer in Texas, and it is commonly believed to be the main source of this pest in cotton. Although the abundance of horsemint, and therefore the fleahopper exposure to it, varies geographically, cotton fleahopper's preference for this native host-plant is maintained across two ecoregions in Texas, TX High Plains (Lubbock area) and Brazos Valley (College Station area). Similarly, preference for horsemint was retained regardless of prior experience with cotton throughout all the life stages of the insect. This fixed preference of cotton fleahopper to horsemint could be because of their ancestral insect-plant interaction, better fitness of cotton fleahopper on horsemint, and relatively low abundance of horsemint compared with cotton. Information gained from this study could be used to implement cultural control practices such as trap cropping, to develop attractants to monitor this pest, or both.
Collapse
Affiliation(s)
- Apurba K Barman
- Department of Entomology, Texas A&M University, 2475 TAMU, College Station, TX 77843, USA
| | | | | | | |
Collapse
|
29
|
|
30
|
Diamond SE, Kingsolver JG. Host plant quality, selection history and trade-offs shape the immune responses of Manduca sexta. Proc Biol Sci 2011; 278:289-97. [PMID: 20702461 PMCID: PMC3013389 DOI: 10.1098/rspb.2010.1137] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Accepted: 07/19/2010] [Indexed: 11/12/2022] Open
Abstract
Immune defences are an important component of fitness. Yet susceptibility to pathogens is common, suggesting the presence of ecological and evolutionary limitations on immune defences. Here, we use structural equation modelling to quantify the direct effects of resource quality and selection history, and their indirect effects mediated via body condition prior to an immune challenge on encapsulation and melanization immune defences in the tobacco hornworm, Manduca sexta. We also investigate allocation trade-offs among immune defences and growth rate following an immune challenge. We found considerable variation in the magnitude and direction of the direct effects of resource quality and selection history on immune defences and their indirect effects mediated via body condition and allocation trade-offs. Greater resource quality and evolutionary exposure to pathogens had positive direct effects on encapsulation and melanization. The indirect effect of resource quality on encapsulation mediated via body condition was substantial, whereas indirect effects on melanization were negligible. Individuals in better condition prior to the immune challenge had greater encapsulation; however, following the immune challenge, greater encapsulation traded off with slower growth rate. Our study demonstrates the importance of experimentally and analytically disentangling the relative contributions of direct and indirect effects to understand variation in immune defences.
Collapse
Affiliation(s)
- Sarah E Diamond
- Department of Biology, University of North Carolina, CB-3280, Coker Hall, Chapel Hill, NC 27599-3280, USA.
| | | |
Collapse
|