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Nihranz CT, Helms AM, Tooker JF, Mescher MC, De Moraes CM, Stephenson AG. Adverse effects of inbreeding on the transgenerational expression of herbivore-induced defense traits in Solanum carolinense. PLoS One 2022; 17:e0274920. [PMID: 36282832 PMCID: PMC9595541 DOI: 10.1371/journal.pone.0274920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 09/06/2022] [Indexed: 01/24/2023] Open
Abstract
In addition to directly inducing physical and chemical defenses, herbivory experienced by plants in one generation can influence the expression of defensive traits in offspring. Plant defense phenotypes can be compromised by inbreeding, and there is some evidence that such adverse effects can extend to the transgenerational expression of induced resistance. We explored how the inbreeding status of maternal Solanum carolinense plants influenced the transgenerational effects of herbivory on the defensive traits and herbivore resistance of offspring. Manduca sexta caterpillars were used to damage inbred and outbred S. carolinense maternal plants and cross pollinations were performed to produced seeds from herbivore-damaged and undamaged, inbred and outbred maternal plants. Seeds were grown in the greenhouse to assess offspring defense-related traits (i.e., leaf trichomes, internode spines, volatile organic compounds) and resistance to herbivores. We found that feeding by M. sexta caterpillars on maternal plants had a positive influence on trichome and spine production in offspring and that caterpillar development on offspring of herbivore-damaged maternal plants was delayed relative to that on offspring of undamaged plants. Offspring of inbred maternal plants had reduced spine production, compared to those of outbred maternal plants, and caterpillars performed better on the offspring of inbred plants. Both herbivory and inbreeding in the maternal generation altered volatile emissions of offspring. In general, maternal plant inbreeding dampened transgenerational effects of herbivory on offspring defensive traits and herbivore resistance. Taken together, this study demonstrates that inducible defenses in S. carolinense can persist across generations and that inbreeding compromises transgenerational resistance in S. carolinense.
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Affiliation(s)
- Chad T. Nihranz
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- School of Integrative Plant Sciences, Cornell University, Ithaca, New York, United States of America
- * E-mail:
| | - Anjel M. Helms
- Department of Entomology, Texas A&M University, College Station, Texas, United States of America
| | - John F. Tooker
- Department of Entomology, The Pennsylvania State University, University Park, PA, United States of America
| | - Mark C. Mescher
- Department of Environmental Systems Science, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Consuelo M. De Moraes
- Department of Environmental Systems Science, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Andrew G. Stephenson
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
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Nihranz CT, Walker WS, Brown SJ, Mescher MC, De Moraes CM, Stephenson AG. Transgenerational impacts of herbivory and inbreeding on reproductive output in Solanum carolinense. AMERICAN JOURNAL OF BOTANY 2020; 107:286-297. [PMID: 31944272 PMCID: PMC7064912 DOI: 10.1002/ajb2.1402] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 09/13/2019] [Indexed: 05/22/2023]
Abstract
PREMISE Plant maternal effects on offspring phenotypes are well documented. However, little is known about how herbivory on maternal plants affects offspring fitness. Furthermore, while inbreeding is known to reduce plant reproductive output, previous studies have not explored whether and how such effects may extend across generations. Here, we addressed the transgenerational consequences of herbivory and maternal plant inbreeding on the reproduction of Solanum carolinense offspring. METHODS Manduca sexta caterpillars were used to inflict weekly damage on inbred and outbred S. carolinense maternal plants. Cross-pollinations were performed by hand to produce seed from herbivore-damaged outbred plants, herbivore-damaged inbred plants, undamaged outbred plants, and undamaged inbred plants. The resulting seeds were grown in the greenhouse to assess emergence rate and flower production in the absence of herbivores. We also grew offspring in the field to examine reproductive output under natural conditions. RESULTS We found transgenerational effects of herbivory and maternal plant inbreeding on seedling emergence and reproductive output. Offspring of herbivore-damaged plants had greater emergence, flowered earlier, and produced more flowers and seeds than offspring of undamaged plants. Offspring of outbred maternal plants also had greater seedling emergence and reproductive output than offspring of inbred maternal plants, even though all offspring were outbred. Moreover, the effects of maternal plant inbreeding were more severe when plant offspring were grown in field conditions. CONCLUSIONS This study demonstrates that both herbivory and inbreeding have fitness consequences that extend across generations even in outbred progeny.
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Affiliation(s)
- Chad T. Nihranz
- Intercollege Graduate Program in EcologyPennsylvania State UniversityUniversity ParkPA16802USA
- Department of BiologyPennsylvania State UniversityUniversity ParkPA16802USA
| | - William S. Walker
- Department of BiologyPennsylvania State UniversityUniversity ParkPA16802USA
| | - Steven J. Brown
- Department of BiologyPennsylvania State UniversityUniversity ParkPA16802USA
| | - Mark C. Mescher
- Department of Environmental Systems ScienceSwiss Federal Institute of Technology (ETH Zurich)CH‐8092ZurichSwitzerland
| | - Consuelo M. De Moraes
- Department of Environmental Systems ScienceSwiss Federal Institute of Technology (ETH Zurich)CH‐8092ZurichSwitzerland
| | - Andrew G. Stephenson
- Intercollege Graduate Program in EcologyPennsylvania State UniversityUniversity ParkPA16802USA
- Department of BiologyPennsylvania State UniversityUniversity ParkPA16802USA
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Müller NA, Kersten B, Fladung M, Schroeder H. RNA-seq of eight different poplar clones reveals conserved up-regulation of gene expression in response to insect herbivory. BMC Genomics 2019; 20:673. [PMID: 31455224 PMCID: PMC6712675 DOI: 10.1186/s12864-019-6048-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 08/20/2019] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Herbivorous insects can have a profound impact on plant growth performance. In some years, canopy damage in poplar plantations exceeds 50% of the total leaf surface, thereby possibly compromising carbon fixation and biomass yield. To assess the transcriptional response of elite poplar clones to insect feeding and to test whether this response varies between different genotypes, we performed an RNA-sequencing experiment. We deeply sequenced the transcriptomes of eight elite clones belonging to three poplar species (Populus trichocarpa, P. nigra and P. maximowiczii), under Phratora vitellinae feeding and control conditions. This allowed us to precisely quantify transcript levels of about 24,000 expressed genes. RESULTS Our data reveal a striking overall up-regulation of gene expression under insect attack in all eight poplar clones studied. The up-regulated genes were markedly enriched for the biological process 'regulation of transcription' indicating a highly concerted restructuring of the transcriptome. A search for potential cis-regulatory elements (CREs) that may be involved in this process identified the G-box (CACGTG) as the most significant motif in the promoters of the induced genes. In line with the role of the G-box in jasmonate (JA)-mediated activation of gene expression by MYC2, several genes involved in JA biosynthesis and signaling were up-regulated in our dataset. A co-expression network analysis additionally highlighted WRKY transcription factors. Within the most prominent expression module, WRKYs were strongly overrepresented and occupied several network hubs. Finally, the insect-induced genes comprised several protein families known to be involved in plant defenses, e.g. cytochrome P450s, chitinases and protease inhibitors. CONCLUSIONS Our data represent a comprehensive characterization of the transcriptional response of selected elite poplar clones to insect herbivory. Our results suggest that the concerted up-regulation of gene expression is controlled by JA signaling and WRKY transcription factors, and activates several defense mechanisms. Our data highlight potential targets of selection and may thus contribute to breeding insect-resistant poplar clones.
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Affiliation(s)
- Niels A Müller
- Thünen Institute of Forest Genetics, Sieker Landstraße 2, 22927, Grosshansdorf, Germany
| | - Birgit Kersten
- Thünen Institute of Forest Genetics, Sieker Landstraße 2, 22927, Grosshansdorf, Germany
| | - Matthias Fladung
- Thünen Institute of Forest Genetics, Sieker Landstraße 2, 22927, Grosshansdorf, Germany
| | - Hilke Schroeder
- Thünen Institute of Forest Genetics, Sieker Landstraße 2, 22927, Grosshansdorf, Germany.
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Herbivory and inbreeding affect growth, reproduction, and resistance in the rhizomatous offshoots of Solanum carolinense (Solanaceae). Evol Ecol 2019. [DOI: 10.1007/s10682-019-09997-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Sandner TM, Matthies D. The effects of stress intensity and stress type on inbreeding depression in Silene vulgaris. Evolution 2016; 70:1225-38. [PMID: 27110935 DOI: 10.1111/evo.12929] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 04/07/2016] [Accepted: 04/13/2016] [Indexed: 02/03/2023]
Abstract
Inbreeding depression (ID) is generally assumed to increase under stressful conditions, but a number of studies have found the opposite pattern, that is that crossed offspring were more capable of exploiting benign conditions. Alternatively, the phenotypic variation hypothesis predicts that not stress intensity, but enhanced phenotypic variation in an environment leads to increased ID. We subjected inbred and crossed offspring of Silene vulgaris to drought, simulated herbivory, copper contamination, and two levels of nutrient deficiency and shade. In contrast to the predominant expectation, most stress treatments decreased inbreeding depression. With increasing nutrient limitation, ID decreased strongly, whereas under increasing shade ID did not change. These differences may be due to purging in the population of origin where conditions are nutrient-poor and dry, but not shaded. In contrast to the greenhouse experiment, ID was higher in a field site than in a more benign common garden. However, the predictions of the phenotypic variation hypothesis were met in both the greenhouse and the field versus garden experiment. The results suggest that there may be no general relationship between ID and stress intensity, but specific effects of stress type and the novelty and variability of the environment.
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Affiliation(s)
- Tobias Michael Sandner
- Department of Ecology, Faculty of Biology, Philipps-University Marburg, D-35043 Marburg, Germany.
| | - Diethart Matthies
- Department of Ecology, Faculty of Biology, Philipps-University Marburg, D-35043 Marburg, Germany
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Menzel M, Sletvold N, Ågren J, Hansson B. Inbreeding Affects Gene Expression Differently in Two Self-Incompatible Arabidopsis lyrata Populations with Similar Levels of Inbreeding Depression. Mol Biol Evol 2015; 32:2036-47. [PMID: 25855783 PMCID: PMC4833072 DOI: 10.1093/molbev/msv086] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Knowledge of which genes and pathways are affected by inbreeding may help understanding the genetic basis of inbreeding depression, the potential for purging (selection against deleterious recessive alleles), and the transition from outcrossing to selfing. Arabidopsis lyrata is a predominantly self-incompatible perennial plant, closely related to the selfing model species A. thaliana. To examine how inbreeding affects gene expression, we compared the transcriptome of experimentally selfed and outcrossed A. lyrata originating from two Scandinavian populations that express similar inbreeding depression for fitness (∂ ≈ 0.80). The number of genes significantly differentially expressed between selfed and outcrossed individuals were 2.5 times higher in the Norwegian population (≈ 500 genes) than in the Swedish population (≈ 200 genes). In both populations, a majority of genes were upregulated on selfing (≈ 80%). Functional annotation analysis of the differentially expressed genes showed that selfed offspring were characterized by 1) upregulation of stress-related genes in both populations and 2) upregulation of photosynthesis-related genes in Sweden but downregulation in Norway. Moreover, we found that reproduction- and pollination-related genes were affected by inbreeding only in Norway. We conclude that inbreeding causes both general and population-specific effects. The observed common effects suggest that inbreeding generally upregulates rather than downregulates gene expression and affects genes associated with stress response and general metabolic activity. Population differences in the number of affected genes and in effects on the expression of photosynthesis-related genes show that the genetic basis of inbreeding depression can differ between populations with very similar levels of inbreeding depression.
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Affiliation(s)
- Mandy Menzel
- Molecular Ecology and Evolution Laboratory, Department of Biology, Lund University, Lund, Sweden Unit of Respiratory Immunopharmacology, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Nina Sletvold
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Jon Ågren
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Bengt Hansson
- Molecular Ecology and Evolution Laboratory, Department of Biology, Lund University, Lund, Sweden
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Chen H, Feng Y, Wang L, Yonezawa T, Crabbe MJC, Zhang X, Zhong Y. Transcriptome profiling of the UV-B stress response in the desert shrub Lycium ruthenicum. Mol Biol Rep 2014; 42:639-49. [DOI: 10.1007/s11033-014-3809-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 10/27/2014] [Indexed: 11/25/2022]
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Carr DE, Roulston TH, Hart H. Inbreeding in Mimulus guttatus reduces visitation by bumble bee pollinators. PLoS One 2014; 9:e101463. [PMID: 25036035 PMCID: PMC4103763 DOI: 10.1371/journal.pone.0101463] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 06/05/2014] [Indexed: 11/19/2022] Open
Abstract
Inbreeding in plants typically reduces individual fitness but may also alter ecological interactions. This study examined the effect of inbreeding in the mixed-mating annual Mimulus guttatus on visitation by pollinators (Bombus impatiens) in greenhouse experiments. Previous studies of M. guttatus have shown that inbreeding reduced corolla size, flower number, and pollen quantity and quality. Using controlled crosses, we produced inbred and outbred families from three different M. guttatus populations. We recorded the plant genotypes that bees visited and the number of flowers probed per visit. In our first experiment, bees were 31% more likely to visit outbred plants than those selfed for one generation and 43% more likely to visit outbred plants than those selfed for two generations. Inbreeding had only a small effect on the number of flowers probed once bees arrived at a genotype. These differences were explained partially by differences in mean floral display and mean flower size, but even when these variables were controlled statistically, the effect of inbreeding remained large and significant. In a second experiment we quantified pollen viability from inbred and self plants. Bees were 37–54% more likely to visit outbred plants, depending on the population, even when controlling for floral display size. Pollen viability proved to be as important as floral display in predicting pollinator visitation in one population, but the overall explanatory power of a multiple regression model was weak. Our data suggested that bees use cues in addition to display size, flower size, and pollen reward quality in their discrimination of inbred plants. Discrimination against inbred plants could have effects on plant fitness and thereby reinforce selection for outcrossing. Inbreeding in plant populations could also reduce resource quality for pollinators, potentially resulting in negative effects on pollinator populations.
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Affiliation(s)
- David E. Carr
- Blandy Experimental Farm, University of Virginia, Boyce, Virginia, United States of America
- * E-mail:
| | - T’ai H. Roulston
- Blandy Experimental Farm, University of Virginia, Boyce, Virginia, United States of America
| | - Haley Hart
- Southeastern High School, Detroit, Michigan, United States of America
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Campbell SA, Halitschke R, Thaler JS, Kessler A. Plant mating systems affect adaptive plasticity in response to herbivory. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 78:481-490. [PMID: 24580720 DOI: 10.1111/tpj.12492] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 02/12/2014] [Accepted: 02/17/2014] [Indexed: 06/03/2023]
Abstract
The fitness consequences of mating system variation (e.g. inbreeding) have been studied for at least 200 years, yet the ecological consequences of this variation remain poorly understood. Most plants are capable of inbreeding, and also exhibit a remarkable suite of adaptive phenotypic responses to ecological stresses such as herbivory. We tested the consequences of experimental inbreeding on phenotypic plasticity in resistance and growth (tolerance) traits in Solanum carolinense (Solanaceae). Inbreeding reduced the ability of plants to up-regulate resistance traits following damage. Moreover, inbreeding disrupted growth trait responses to damage, indicating the presence of deleterious mutations at loci regulating growth under stress. Production of the phytohormones abscisic and indole acetic acid, and wounding-induced up-regulation of the defence signalling phytohormone jasmonic acid were all significantly reduced under inbreeding, indicating a phytohormonal basis for inbreeding effects on growth and defence trait regulation. We conclude that the plasticity of induced responses is negatively affected by inbreeding, with implications for fragmented populations facing mate limitation and stress as a consequence of environmental change.
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Affiliation(s)
- Stuart A Campbell
- Department of Ecology & Evolutionary Biology, Cornell University, Ithaca, NY, 14853, USA
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Jensen P, Overgaard J, Loeschcke V, Schou MF, Malte H, Kristensen TN. Inbreeding effects on standard metabolic rate investigated at cold, benign and hot temperatures in Drosophila melanogaster. JOURNAL OF INSECT PHYSIOLOGY 2014; 62:11-20. [PMID: 24456661 DOI: 10.1016/j.jinsphys.2014.01.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 12/23/2013] [Accepted: 01/09/2014] [Indexed: 06/03/2023]
Abstract
Inbreeding increases homozygosity, which is known to affect the mean and variance of fitness components such as growth, fecundity and mortality rate. Across inbred lines inbreeding depression is typically observed and the variance between lines is increased in inbred compared to outbred lines. It has been suggested that damage incurred from increased homozygosity entails energetic cost associated with cellular repair. However, little is known about the effects of inbreeding on standard metabolic rate. Using stop-flow respirometry we performed repeated measurements of metabolic rate in replicated lines of inbred and outbred Drosophila melanogaster at stressful low, benign and stressful high temperatures. The lowest measurements of metabolic rate in our study are always associated with the low activity period of the diurnal cycle and these measurements therefore serve as good estimates of standard metabolic rate. Due to the potentially added costs of genetic stress in inbred lines we hypothesized that inbred individuals have increased metabolic rate compared to outbred controls and that this is more pronounced at stressful temperatures due to synergistic inbreeding by environment interactions. Contrary to our hypothesis we found no significant difference in metabolic rate between inbred and outbred lines and no interaction between inbreeding and temperature. Inbreeding however effected the variance; the variance in metabolic rate was higher between the inbred lines compared to the outbred control lines with some inbred lines having very high or low standard metabolic rate. Thus genetic drift and not inbreeding per se seem to explain variation in metabolic rate in populations of different size.
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Affiliation(s)
- Palle Jensen
- Department of Bioscience, Aarhus University, Ny Munkegade 116, DK-8000 Aarhus C, Denmark; Department of Molecular Biology and Genetics, Aarhus University, Blichers Allé 20, DK-8830 Tjele, Denmark.
| | - Johannes Overgaard
- Department of Bioscience, Aarhus University, Ny Munkegade 116, DK-8000 Aarhus C, Denmark
| | - Volker Loeschcke
- Department of Bioscience, Aarhus University, Ny Munkegade 116, DK-8000 Aarhus C, Denmark
| | - Mads Fristrup Schou
- Department of Bioscience, Aarhus University, Ny Munkegade 116, DK-8000 Aarhus C, Denmark
| | - Hans Malte
- Department of Bioscience, Aarhus University, Ny Munkegade 116, DK-8000 Aarhus C, Denmark
| | - Torsten Nygaard Kristensen
- Department of Biotechnology, Chemistry and Environmental Engineering, Section of Biology and Environmental Science, Aalborg University, Sohngaardsholmsvej 57, DK-9000 Aalborg, Denmark
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Carr DE, Eubanks MD. Interactions between insect herbivores and plant mating systems. ANNUAL REVIEW OF ENTOMOLOGY 2014; 59:185-203. [PMID: 24160428 DOI: 10.1146/annurev-ento-011613-162049] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Self-pollination is common in plants, and limited seed and pollen dispersal can create localized inbreeding even within outcrossing plants. Consequently, insects regularly encounter inbred plants in nature. Because inbreeding results in elevated homozygosity, greater expression of recessive alleles, and subsequent phenotypic changes in inbred plants, inbreeding may alter plant-insect interactions. Recent research has found that plant inbreeding alters resistance and tolerance to herbivores, alters the attraction and susceptibility of plants to insects that vector plant pathogens, and alters visitation rates of insect pollinators. These results suggest that interactions with insects can increase or decrease inbreeding depression (the loss of fitness due to self-fertilization) and subsequently alter the evolution of selfing within plant populations. Future work needs to focus on the mechanisms underlying genetic variation in the effects of inbreeding on plant-insect interactions and the consequences of altered plant-insect interactions on the evolution of plant defense and plant mating systems.
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Affiliation(s)
- David E Carr
- Blandy Experimental Farm, University of Virginia, Boyce, Virginia 22620;
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García C, Ávila V, Quesada H, Caballero A. Are transcriptional responses to inbreeding a functional response to alleviate inbreeding depression? Fly (Austin) 2013; 7:8-12. [PMID: 23639890 DOI: 10.4161/fly.22559] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Previous studies addressing the relationship between gene regulation and inbreeding depression did not allow for discerning the changes that alleviate the depression from those that generate it. We directly addressed this question by analyzing changes in gene expression, using Affymetrix 2.0 arrays in Drosophila melanogaster inbred sublines differing in their magnitudes of inbreeding depression relative to the expression in an outbred control. The total number of arrays analyzed was 27, with 9,133 probe sets showing a significant signal of expression. We found that for those genes differentially expressed between inbred and outbred sublines, most of them showed a pattern of expression consistent with a protective role against inbreeding effects. The observed increase in depression was presumably related to an inability of the genome to do the appropriate expression adjustments. Expression changes detected in our study showed a clear specificity of RNA-splicing and energy derivation functions. Thus, it appears that most of the observed changes in gene expression associated with inbreeding may occur predominantly to alleviate inbreeding depression, i.e., as a protection against the effects of inbreeding.
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Affiliation(s)
- Carlos García
- Department Xenética, Facultade de Bioloxía, CIBUS Campus Sur, Universidade de Santiago de Compostela, Santiago de Compostela, Spain.
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Kalske A, Mutikainen P, Muola A, Scheepens JF, Laukkanen L, Salminen JP, Leimu R. Simultaneous inbreeding modifies inbreeding depression in a plant-herbivore interaction. Ecol Lett 2013; 17:229-38. [PMID: 24304923 DOI: 10.1111/ele.12223] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 09/26/2013] [Accepted: 10/28/2013] [Indexed: 11/30/2022]
Abstract
Because inbreeding is common in natural populations of plants and their herbivores, herbivore-induced selection on plants, and vice versa, may be significantly modified by inbreeding and inbreeding depression. In a feeding assay with inbred and outbred lines of both the perennial herb, Vincetoxicum hirundinaria, and its specialist herbivore, Abrostola asclepiadis, we discovered that plant inbreeding increased inbreeding depression in herbivore performance in some populations. The effect of inbreeding on plant resistance varied among plant and herbivore populations. The among-population variation is likely to be driven by variation in plant secondary compounds across populations. In addition, inbreeding depression in plant resistance was substantial when herbivores were outbred, but diminished when herbivores were inbred. These findings demonstrate that in plant-herbivore interactions expression of inbreeding depression can depend on the level of inbreeding of the interacting species. Furthermore, our results suggest that when herbivores are inbred, herbivore-induced selection against self-fertilisation in plants may diminish.
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Affiliation(s)
- Aino Kalske
- Section of Ecology, University of Turku, Turku, Finland
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